ISSN:0003-2654    

DOI:10.1039/AN94671FP015

出版商:RSC    

年代:1946

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN94671FX021

出版商:RSC    

年代:1946

数据来源: RSC

ISSN:0003-2654    

DOI:10.1039/AN94671BX023

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

JUNE 1946. Vol. 71 No. 843 Symposium on Chromatography The following four Papers on Chromatography were read and discussed at the Meeting of the Physical Methods Group in London on Tuesday February 26th 1946. The Discussion follows the last of the four on p. 265. General Principles of Chromatographic Analysis BY F. A. ROBINSON CHROMATOGRAPHIC adsorption was first used in 1906 by the Russian botanist Tswett. He poured a petroleum ether extract of green leaves on to a column of finely powdered calcium carbonate and observed the formation of a pale-yellow ring in the upper part of the column with two green zones immediately below it and three yellow bands below these. On washing the column with the pure solvent a process now known as “development,” all the bands became completely separated from one another enabling the column to be cut up and the individual pigments eluted from each separate portion.This is an example of what might be termed “classical” chromatography applied to the separation of coloured pigments. Chromatography has been extensively employed for the characterisation of the individual components of naturally occurring pigments such as carotenoids and pterins; in fact it is difficult to see how progress in either of these fields would have been possible had the technique not been available. It has also been used for the isolation of compounds present in minute amounts in natural products or in synthetic mixtures and for the purification of compounds that cannot readily be purified by crystallisation. The application of chromatography is by no means confined to the investigation of coloured substances however in spite of what the name suggests for it has also been proved of great value in the isolation and purification of polycyclic hydrocarbons sterols alkaloids, vitamins and hormones.In practice the only difference between the chromatography of 25 252 ROBINSON GENERAL PRINCIPLES OF CHROMATOGRAPHIC ANALYSIS coloured and colourless substances is that with the former the position of each component on the column is self-evident whereas with the latter various devices have to be employed to indicate the position of the bands. The earliest procedure for separating colourless components was to cut the column empirically and test the eluate of each part by a suitable physical or chemical test.This method is not particularly satisfactory however for as often as not the component sought is contaminated by another constituent of the mixture and a second or even third chromato-gram has to be prepared to effect complete separation. Where the procedure is applicable a particularly simple methodl of detecting the position of the bands is examination of the column in light from a mercury vapour lamp; this reveals the presence of any substance that fluoresces in ultra-violet light and often produces a series of coloured bands sufficiently distinctive to enable the column to be cut as in “classical” chromatography. Another method of detecting the position of a particular band is the so-called “brush method,’’2 in which the column is extruded from the tube and painted with a suitable reagent ; antimony trichloride solution for example can be used to detect the position of a vitamin A band.This method has the disadvantage that the progress of development cannot be followed. In some instances instead of chromatographing the substances themselves it is preferable to chromatograph suitable coloured derivatives. For example carbonyl compounds can be converted into dinitrophenylhydrazones,3 and sugars or amino acids reacted with azobenzene-4-carboxylic acid ~hloride.~ The resulting coloured derivatives are then chromatographed, the column is cut up according to the position of the coloured bands and the individual compounds are liberated from each fraction by hydrolysis. Another satisfactory technique for indicating the position of a substance is to find a dyestuff with the same adsorption affinity and add this to the mixture being chromatographed.The dyestuff is adsorbed on the column in substantially the same position as the substance to be isolated. Br~ckmann,~ for instance used Sudan I11 to indicate the position of the vitamin D band during the process of isolating it from fish liver oil. A large variety of adsorbents has been used in chromatography depending on the nature of the substances to be separated. The most strongly adsorbed of all organic compounds are acids and bases ; then come hydroxyl- amino- and thio-compounds then aldehydes ketones and esters and finally halogen derivatives and hydrocarbons. In a homologous series adsorption affinity increases with the number of conjugated double bonds and unsaturated compounds are more strongly adsorbed than the corresponding saturated compounds, Increasing the number of atomic rings increases adsorption affinity and so does the intro-duction of polar groups.With positional and cis-trans isomers the one with the greater dipole moment will be the more strongly adsorbed. Strongly adsorbed substances such as carotenoids can readily be chromatographed on weak adsorbents such as calcium carbonate. Indeed the use of a strong adsorbent with these substances would result in the bands being bunched together at the top of the column instead of being distributed over its whole length. On the other hand with a feeble adsorbent all the material may pass into the filtrate. Only experience will indicate the most suitable adsorbent for a particular purpose.The materials with the highest adsorption affinity are charcoal activated alumina and some of the specially prepared adsorbent earths whilst the weakest of all adsorbents are the carbohydrates such as sucrose starch and inulin. Inter-mediate in activity are magnesia lime silicic acid and calcium phosphate at the upper end of the scale and at the lower end talc and the alkali metal and alkaline earth carbonates. It must be realised that the activity of an adsorbent varies with the mode of preparation, and aluminium oxides with varying degrees of activity are madea by heating aluminium hydroxide to strong-red heat and then partially deactivating it by shaking for shorter or longer periods with moist air.For this reason the use of standardised adsorbents is recommended. Brockmann6 standardised alumina and other adsorbents by noting their behaviour towards a series of dyestuffs with increasing adsorption affinity whilst Miiller’ advocated a calorimetric method based on the observation that the amount of heat evolved on treating different grades of alumina with light petroleum is proportional to their relative adsorption affinities. Another method of comparing the properties of different batches of adsorbent was adopted by Le Rosen,* who made use of the following four terms to define density porosity and adsorptive power ROBINSON GENERAL PRINCIPLES OF CHROMATOGRAPHIC ANALYSIS length of adsorbent column containing unit volume of solvent length of unfilled tube required to contain same volume of solvent s = 253 V = rate of flow (mm./min.) of developing solvent through column when a state of T, = time (sec.) required for solvent to penetrate 50mm.into an initially dry column constant flow has been reached (9 x 75 mm.) under the vacuum of a water pump rate of movement (mm./min.) of front edge of adsorbate zone VC R = With different batches of silicic acid S had much the same value but the values of V, and T, varied considerably. Adsorbents for which V was between 10 and 50 mm./min. and T, between 20 and 100 sec. gave the best results. The value of R varied with the treatment to which the adsorbent had been subjected; values of 0.1 to 0.3 gave satisfactory chromatograms that is the rate at which the zone passes down the column should be one-tenth to one-third the rate of flow of the developing solvent.The choice of solvents for use in the development of chromatograms that is in separating the adsorbed material into distinct bands or zones is also wide. In general the less polar the solvent the more readily will the solute be retained on the column and the more polar the solvent the more readily will the solute be eluted. The weakest eluants are the four grades of light petroleum but these are used for the initial adsorption rather than for develop-ment. Benzene carbon tetrachloride cyclohexane ether and acetone are more commonly used for development and a mixture of light petroleum and benzene is particularly popular. Stronger eluants are ethylene dichloride chloroform the alcohols and water whilst the most active of all are pyridine acids and mixtures of acids with bases.One of the most useful methods of separating the components of a colourless mixture is based on such differences in eluant power and is known as “fluid chromatography.” In this method a series of solvents of gradually increasing eluant power is poured through the column in succession each eluate is collected separately and its constituents are examined. Charcoal has not been used to any great extent in chromatography because of the diffi-culty of detecting the position of the bands although its high adsorption affinity would be an obvious advantage in many instances. During the last two or three years however, Tiseliusg has described a method of overcoming this difficulty by forcing the solution to be examined under pressure upwards through a column of charcoal and examining in an optical system the liquid which emerges at the top.A number of Schlieren boundaries are formed, their relative positions depending on the degree of adsorption of the individual components, which are more or less retarded as compared with the movement of the meniscus of the super-natant liquid. The volume of liquid between each boundary and the meniscus is known as the “retardation volume,” and is greatest with the substances most tenaciously held by the charcoal. The retardation volumes of a series of amino acids were measured and found to vary from 0 for glycine to 122 ml. per g . for hippuric acid. A method of separating Iysine, valine and alanine was described.Tiseliuslo has also introduced another technique termed “displacement chromatography.’’ With strong adsorbents it is often difficult to find solvents of sufficient eluant power to over-come the adsorption affinity of the adsorbate and Tiselius adopted the procedure of develop-ing charcoal columns with a solution of a strongly adsorbed substance such as ephedrine; this was found to elute the less strongly adsorbed fractions from a mixture of mono- and poly-saccharides. Of theoretical though probably not of practical importance is the reversed chromato-gram11 in which an adsorbent is poured into a column of the solution to be analysed; the com-ponent with the highest adsorption affinity is carried to the bottom whilst that with the lowest is either adsorbed in the top layers or remains behind in solution.Chromatography has also been applied to the separation of substances in the vapour phase. If a mixture of benzene and cyclohexane,12 together with a carrier gas such as hydrogen or nitrogen is passed through a tube containing silica gel the emergent gases contain cyclo-hexane almost free from benzene. Benzene and carbon tetrachloride can be similarly separated. Again when alcohol - water vapour is passed through a column of charcoaI,13 the ratio of alcohol is higher in the adsorbate than in the vapour phase whereas in static adsorption the adsorbate is richer in water. This is due to the fact that although charcoal adsorbs water preferentially from the vapour the rate of adsorption of alcohol is considerabl 254 ROBINSON GENERAL PRINCIPLES OF CHROMATOGRAPHIC ANALYSIS greater than that of water so that in the continuous flow method the former displaces the latter; the ratio of alcohol in the adsorbate is in fact increased by increasing the rate of passage through the adsorbent.Similar results are obtained with propanol - water vapour, whilst with mixtures of water methanol and ethanol or of water ethanol and butanol, almost complete adsorption of the higher alcohol occurs in each instance. The processes so far described result in the separation of substances according to their relative adsorption affinities but the chromatographic principle that is the continuous flow of a solution through a stationary column of solid has also been used to separate substances by taking advantage of other properties.The use of columns of zeolite for the recovery from solution of basic substances such as aneurine is now a fairly familiar procedure in analytical chemistry; it is an example of ion exchange chromatography in which sodium ions are displaced by the basic substance. Ion exchange resins14 are now being used for the same purpose e.g. Amberlite I.R. 100 for adsorbing basic substances and Amberlite I.R. 4 for acidic substances. They have been used for the separation of amino acids and vitamins. Alumina has also been used for the separation of amino acids,15 the process depending on ion exchange rather than adsorption. Ordinary alumina contains sodium ions which can be displaced by basic amino acids whilst acid-washed alumina contains hydrogen ions which can be displaced by acidic amino acids.Neutral amino acids can be separated from one another by chromatographing on acid-washed alumina in presence of 10% formaldehyde,l6 which shifts the fiK into the acid region. Under these conditions glycine and serine are strongly adsorbed whilst alanine valine leucine and proline are not. A third type of chromatography discussed in more detail by Synge,29 is partition chromatography in which a column of solid such as silica gel,17 papeP or starchlg is used to support an aqueous phase enabling substances to be separated by distribution between water and an organic solvent on the chromatographic principle. The result is the same as that obtained by repeatedly distributing the solutes between the two liquid phases, and such a chromatogram as pointed out by Martin and Synge is analogous to a fractionating column.Recently this type of chromatogram has been further developed by adsorbing strong buffer solutions on the silica gel in place of water,20 or by mixing the carbonate of an alkali or alkaline earth with the silica.21 The mechanism is obviously complex the result probably being due to a combination of partition and neutralisation by the buffer or metal carbonate. An interesting development in chromatography is the use of columns of specific organic reagents for the separation of inorganic ions. Thus columns of 8-hydroxyquinoline22 have been used for the separation of VO,' WO,' Cu" BY' Ni" Co" Zn" Fe"' and UO," which are adsorbed in that order; this corresponds mainly to the relative solubilities of the hydroxy-quinolates in water but also appears to depend on +H.Columns of violuric acid and of 5-oxo-4-oximino-3-phenyl-isoxazoline23 have been used for the separation of Na' K' Mg" and Ca" from one another. The first attempt to explain the phenomena observed during the process of chromato-graphy was made by Wilson,24 who developed equations to express the distribution of one solute and of two solutes on a column. He assumed that equilibrium between the adsorbed material and the solution was reached instantaneously that the volume of the interstices between the particles of adsorbent was negligible and that the effects of diffusion could be neglected. From these equations Wilson predicted that the chromatogram formed from a solution containing only one solute should consist of a single band which would maintain a constant width and sharply defined edges as long as the solvent used for development was the same as that used in forming the band.This prediction was tested experimentally by Cassidy and Wood,24 who found that although the behaviour of the front edge of the zone was in accordance with Wilson's prediction the rear edge became diffuse on development; this discrepancy was undoubtedly due to the fact that some of the assumptions made were unjustifiable. Wilson also predicted that the first colour zone of a mixed chromatogram formed before development occurs should contain some of each solute initially present in pro-portions determined by the initial concentrations and the adsorption isotherms whereas it had previously been supposed that this zone contained only the most strongly adsorbed solute.This prediction was verified by experimental observation. A different set of assumptions was made by Martin and Synge,l7 who took into account the effects of diffusion and the possibility that equilibrium was not attained instantaneously ROBINSON GENERAL PRINCIPLES OF CHROMATOGRAPHIC ANALYSIS 255 but assumed that the solute had a linear adsorption isotherm. The column was regarded as consisting of a number of theoretical plates and the problem was treated as analogous to that of a fractionating column. Although adsorption isotherms are seldom linear and the results from this mode of treatment were therefore only an approximation they did emphasise the extraordinarily high efficiency of chromatographic separations ; whereas the height equivalent to a theoretical plate (H.E.T.P.) of the best distillation columns is of the order of 1 cm.that of a chromatogram was found to be 0-002 cm. De Vault25 and Weiss26 criticised Wilson’s theory and showed that his assumptions were not justified. The former developed equations for both the front and rear boundaries and showed that development of an initially sharp band would be expected to give a diffuse rear boundary although the front boundary would continue to be sharp. Weiss reached similar conclusions and emphasised the fundamental character of the threshold volume (Vt that is, the volume of solvent required to develop the column until the front edge of the zone reaches the bottom).\Veil-hlalherbe27 measured the threshold volumes for benzpyrene under different conditions and concluded that where the only variable in a chromatographic system is the nature of the solvent the threshold volume is a measure of eluant power. Similarly where the solvent and solute are the same it is possible to calculate from the threshold volume the amount of adsorbent and the minimum size of column necessary to ensure the full development of a solution. It is clear therefore that considerable progress has been made towards an understanding of the theory of chromatography and that it is now possible to express the behaviour of a simple chromatogram more or less exactly in mathematical terms. With complicated chromatograms however the mathematical treatment would be extremely involved; the only really satisfactory method of determining the optimal conditions to be employed in such instances remains-and for some time is likely to remain-the method of trial and error.i . 2. 3. 4. 3 . 6. 8. 9. 10. 11. 2. 13. 14. 15 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. - 4 . REFERENCES Winterstein A and Schon K. 2. fihysiol. Chem. 1934 230 139; Karrer P. and Schopp K., Helv. chim. Acta 1934 17 693. Zechmeister L. Cholnoky L. and Ujhelyi E. Bull. SOC. Chim. biol. 1936 18 1885. Strain €3. H. Science 1936 83 241. Coleman G. H. and Farnham -4. G. Proc. Iowa Acad. SEZ’. 1941 48 246; Karrer P. Keller R., Brockmann H. 2. physiol. Chem. 1936 241 104; Brockmann H.and Busse A. Id. 1937 249, Brockinann H. and Schodder H. Ber. 1941 74 73. Miiller P. B. Verhaizdl. Vev. schweiz. Physiol. 1942 21 29; Helv. chim. Acta 1943 26 1945. Le Rosen A. L. J . Amer. Chem. Soc. 1942 64 1905; 1945 67 1683. Tiselius A Arkiv. Kemi Mineral. Geol. 1940 1 4 ~ No. 22; 1941 1 4 ~ No. 32; 1941 1 5 ~ No. 6; Tiselius A. and Hahn L. KolZoid-Z. 1943 105 177; Tiselius &4. Arkiv. Kemi Mineral. GeoZ., Lowmaii A. Science 1942 96 211. Hesse G. and Tschacholin B. Naturwiss. 1942 30 587. Amphoux B. Ann. claim. 1944 19 1. Myers R. J. Eastes J. W. and Myers F. J. Ind. Eng. Chem. 1941,33 697; Cleaver C. S. Hardy, Turba F. and Richter M. Ber. 1942 75 340; Wieland T. Naturwiss. 1942 30 374; 2. physiol. Schramm G. and Primosigh J. Ber. 1943 76 373.Martin A. J. P. and Synge R. L. M. Biochem. J. 1941,35 1358; Gordon A. H. Martin A. J. P., Consden R. Gordon A. H. and Martin A. J. P. Id. 1944 38 224. Elsden S. H . and Synge,’R. L. M. I d . 1944 38 ix; Synge R. L. M. Id. 1944 38 285. Levi A. A. Terjesen S. G. and I.C.I. Ltd. Brit. Pat. 569,844. Catch J. R. Cook A. H. and Heilbron I. M. Natum 1942 150 633; Therapeutic Research Cor-Erlenmeyer H. and Dahn H. Helv. chim. A d a 1939 22 1369. Erlenmeyer H. and Schoenauer W. Id. 1941 24 878; Erlenmeyer H. and Schmidlin J. Id., Wilson J. N. J . Amev. Chem. SOC. 1940 62 1583. Cassidy H. G. and ?Vood S. E. I d . 1941 63 2628. De Vault D. Id. 1943 65 532. Weiss J. J Chenz. SOG. 1943 297. Weil-Malherbe H. Id. 1943 303. Synge R. L. M. ANALYST 1946 71 256. and Szonyi G.Helv. chim. A d a 1943 26 38. 176. Science 1941 94 145. 1948 1 6 ~ No. IS. R. A. and Cassidy H. G. J . Arner. Chem. SOC. 1945 67 1343. Chew. 1942 273 24. and Synge R. L. M. Id. 1943 37 79. poration Ltd. Heilbron I. M. Cook A. H. and Catch J. R. Brit. Pat. 558,320. 1213. GLAXO LABORATORIES LTD. GREENFORD. MIDDLESE 256 SYNGE PARTITIOX CHROMATOGRAPHY Partition Chromatography BY R. L. M. SYNGE RG BIN SON^^ has described how on developing a chromatogram in which the distribution isot ierms between the moving and stationary phases for the substances undergoing analysis are ,inear relatively sharp bands will result. Deviations of the isotherms from linearity as with adsorption of the usual Freundlich type lead to much spread bands with sharp front edges and elongated “tails,” while deviations in the opposite sense when they occur give conversely spread bands with sharp rear edges and diffuse “fronts.” A.J. P. Martin and I were led by considerations of this kind stimulated by practical work with counter-current liquid - liquid extraction trains,l to the idea that delicate separations based on the distribution of solutes between two liquid phases should be capable of realisation iE a chromatographic set-up since Henry’s law which is approximately obeyed in a large number of systems provides linear distribution isotherms. Our expectations were fulfilled in 1941, when we tried chromatograms in which powdered silica gel was saturated with the aqueous phase of a chloroform - water mixture the chloroform phase being used for development of the chromatogram.2 Since then a considerable number of applications of partition chroma-tography have been described and I will enumerate these briefly before passing on to a discussion of the physico-chemical processes occurring in partition chromatograms.To understand these processes is important since on this basis the analyst can decide whether a problem may best be tackled by partition chromatography or some other technique and can further be guided as to choice of materials and mode of procedure. First however it should be said that the application of partition chromatography seems to be limited in its present form to substances that can diffuse freely through the gel-like materials used in the chromatograms. Since the pores of these are of molecular dimensions, the materials so far employed are inherently unsuited for the fractionation of colloid sub-stances.Further the very large surfaces exhibited by the gel substances will provide adsorption on the gel structures and in certain instances this adsorption more than the partition between the two liquid phases may dominate the effective distribution isotherm in the chromatogram. Such adsorption effects have often been noticed in partition chromatography, and have been partially mitigated by incorporating eluants in the developing liquid and in the case of silica gel by special precautions in its preparation. But it will probably turn out that there are groups of substances whose molecular size or extreme adsorption renders them unsuited for partition chromatography while nevertheless being capable of undergoing useful separations through distribution between bulk liquid phases.For such substances, counter-current liquid - liquid extraction arrangements are likely to find extensive use on the laboratory ~cale.1~39~9~ So far only silica gel cellulose and starch grains have been described for use as supporting substances in partition chromatography. All these tend to hold the more polar (aqueous) member of liquid phase pairs. There is a very real need for study of the application of hydrophobic gel structures. With the more polar as the flowing phase many new separations, for example of higher fatty acids and sterols will become amenable to partition chroma-t ography . There seems no reason why partition chromatography should not be effected with a gaseous moving phase.Partition chromatography permits the location of colourless acid or basic substances by incorporation of an indicator in the aqueous phase of the chromatogram. In addition to this, the usual methods for locating colourless substances are applicable. SILICA GEL-using silica gel the original2 separation of acetylamino acids has been ex-tended to the quantitative analysis of some amino acids6~7~s~9~10~11~12~13~14~15~1~~ and to separations of peptides,16 but cf. ll. For these purposes various special indicators have been d e v e l ~ p e d . ~ ~ J ~ Sangerls has worked out how to separate the yellow N-2 :4-dinitrophenyl derivatives of nearly all the naturally occurring amino acids and has thus by substitution and sub-sequent hydrolysis been able to identify the free amino groups of insulin,18 “gramicidin S”19 and a number of other proteins.. Wieland and Fremerey20 have separated amino acids as their blue copper complexes. Elsden,21 following a suggestion of Lester has worked out an analytical procedur SYNGE PARTITION CHROMATOGRAPHY 257 for micro-determination of the normal fatty acids from acetic to valeric. These acids are weaker than the acetylamino acids; the indicators used with the latter are therefore in-sensitive and bromocresol green has been employed cf.*%. Bells has applied partition chromatography to the separation of methylated sugars and has thus been able to improve the accuracy of end-group assay of methylated poly-saccharides while employing smaller quantities than previously.CELLuLosE-Using cellulose in the form of filter paper Consden Gordon and cf. 25 have worked out a very valuable qualitative ultra-micro testing procedure for the identification of amino acids and peptides. A great feature of their arrangement is that each fraction obtained chromatographically can be re-analysed with a second solvent simply by turning the sheet of paper which constitutes the chromatogram through a right angle before the second run. In this way a “two-dimensional” chromatogram giving a charac-teristic arrangement of spots on the sheet of paper results. The spots are located by spraying the dried sheet with a solution of ninhydrin or other colour test reagent. The method has found valuable applications in the protein field and in pathological work many of which are not yet p~blished.llf21~~,~7 Special mention should be made of Edman’s use of the method in the purification and amino acid analysis of hypertensin28 (angiotonin).It is reasonable to expect applications in fields other than protein chemistry. STARCH GRAINS-using starch grains Elsden and 129J1 have realised on a preparative scale some of the separations worked out as mentioned with paper on the ultra-micro scale. An important application using a buffered aqueous phase in the chromatogram has been evolved by workers at the Blackley I .C.I. Laboratories-unpublished30; cf. 22,31. I under-stand that this has proved of value in the purification and separation of the penicillins. I will explain the underlying principle shortly.Turning to a theoretical consideration of partition chromatography it is evident from what has been said by Robinson,34 that the band-rate of each substance is determined by its effective distribution isotherm between stationary particles and moving liquid. Equili-brium must be attained within a fraction of a second. Given this condition if the effective distribution isotherm is approximately linear fairly sharp bands will result. Deviations from linearity will have the effects already mentioned. We can now examine the various physico-chemical equilibrium factors which jointly determine the isotherm. (1) Distribution of a single molecular species between the two liquid phases-This equi-librium usually obeys Henry’s law and ideally should determine the distribution isotherm in ordinary partition chromatography.The partition of organic molecules between liquid phases has not been studied in the detail which it merits. The simple theory as developed by B r ~ n s t e d ~ ~ > ~ suggests that for particular solvent systems the coefficient for a given molecule can be calculated from constants for each of its component groups (much like the parachor). This theoretical basis is very advantageous for planning analytical operations with new substances. It also leads to the generalisation that the partition coefficient depends on the nature of the various groups in the molecule more than on their geometrical relationship. In adsorption work geometrical relations are of greater importance. One can picture crudely that in adsorption groups are presented to a flat surface so that only a part of the molecule determines the effect while in partition the whole of the molecule is in contact with solvent.Thus €or separating the fatty acid series one would choose partition chromatography whereas for separating structural orfho meta and para isomers one would choose adsorption chroma-tography. Much remains to be done in assessing the affinity of different solvents for different radicles and towards improving the theory of solubility in mixed solvents. (2) Adsorption on the gel structure-This factor when of the Freundlich type spreads the bands and is thus deleterious. Linear adsorption slows the bands without spreading them but may be deleterious by having a greater effect on a faster than on a slower moving component thus impairing separation.(3) Equilibria between diflerent molecular species-These effects are well exemplified in the partition chromatography of organic acids where the occurrence of double associated molecules in the organic solvent phase and ionic dissociation in the aqueous phase both lead to deviations of the isotherm from linearity in the same sense and thus in ordinary partition chromatograms to “tailing” of the bands 258 SYNGE PARTITION CHROMATOGRAPHY The ionic dissociation effect may be controlled by loading the aqueous phase with a Then in the aqueous phase the #H will be constant suitable unextractable buffer mixture. therefore the ratio of un-ionised to ionised acid will be maintained constant since cA’1 is constant.[HA1 Thus by using buffered columns three desirable effects may be realised when the ionised molecular species does not appreciably enter the organic solvent phase : (a) The bands of ionising substances may be rendered sharp by promoting linearity in the effective distribution isotherm. (b) By controlling the pH of the buffer the distribution coefficient of ionising substances m2y be varied over a wide range. Thus substances which in the un-ionised forni would travel too fast for separation in the chromatogram may be slowed to any desired rate. (c) Ionising substances differing in ~!IK but having similar partition coefficients in the un-ionised state may be separated on the basis of their different ionising strengths by partition chromatography at a suitable #H.Craig and colleagues5 have presented a detailed treatment of the theory of such separations and have described applications using bulk liquid extraction. In general other chemical equilibria than ionisation are amenable to the same sort of treatment provided that equilibrium is established sufficiently rapidly. One can envisage use being made of complex formation and other chemical reactions for determining dis-tribution isotherms in partition chromatograms; the range of molecular or atomic (isotopic) properties on whose basis separations may be effected chromatographically is thus indefinitely extended. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 15a. 16. 17. 18. 19. 20. 21. 22. 22a. 23. 24. 25. 26.27. 28. 29. 30. 31. 32. 33. 34. REFERENCES Martin A. J. P. and Synge R. L. M. Biochem. J. 1941 35 91. - ___ I d . 1358. Cornish R. E. Archibald R. C. Murphy E. A. and Evans H. M. Ind. Eug. Chetrt. 1934 26 397. Craig L. C. J . Biol. Chem. 1944 155 519. Craig L. C. Golumbic C. Mighton H. and Titus E. Id. 1945 161 321. Gordon A. H. Martin A. J. P. and Synge R. L. M. Biochem. J. 1943 37 79. Id. 86. Id. 313. Id. 538. -- Id. 1944 38 65. Synge R. L. M. Id. 285. Bailey K. Adv. Protein Chem. 1944 1 289. Chibnall A. C. Procter Memorial Lecture 1946 J . Int. SOC. Leather Trades Chena. 1946 30 1. Hanby W. H. and Rydon H. N. Biochem. J. 1946 (in press). Blackburn S. Consden R. and Phillips H. Id. 1944 38 25. Gordon A. H. Martin A. J. P. and Synge R.L. M. I d . 1943,37 92. Liddell H. F. and Rydon H. N. Id. 1944 38 68. Sanger F. Id. 1945 39 507. - I d . (in press). Weland T. and Fremerey H. Ber. 1944 77 234. Elsden S. R. Biochem. J. 1946 (in press). Smith E. L. Id. 1942 36 Proc. xxii. * Ramsey L. L. and Patterson W. I. J . Assoc. 08. Agric. Chem. 1945 28 644. Bell D. J. J . Chem. SOC. 1944 473. Consden R. Gordon A. H. and Martin A. J. P. Biochem. J. 1944 38 224. Gordon A. H. Martin A. J. P. and Synge R. L. M. Id. 1943,37 Proc. xiii. Consden R. Gordon A. H. Martin A. J P. Kosenheim O. and Synge R. L. M. Id. 1945,39,251. Dent C. E. 1946. Edman P. Arkiv. Kemi Mineral. Geol. 1945 22~ No. 3. Elsden S. R. and Synge R. L. M. Biochem. J. 1944 38 Proc. ix. Levi A. A. Terjesen S. G. and I.C.I. Ltd. Brit.Pat. 569,844. Catch J. R. Cook A. H. and Heilbron I. M. Nature 1942 150 633 (cf. Brit. Pat. 558,320). Bransted J. N. 2. phys. Chem. Bodenstein Festband 1931 p. 257. - Comptes rend. Trav. Lab. Carlsberg 1938 22 99. Robinson F. A. R. ANALYST 1946,71 251. ------- Id. 1945 39 363. (Appfications in clioical pathology-to be published.) LISTER INSTITUTE FOR PREVENTIVE MEDICINE LONDON S.W. WILLIAMS CHROMATOGRAPHY IN THE ANALYSIS OF FATTY OILS 259 Chromatography in the Analysis of Fatty Oils BY K. A. WILLIAMS Is the early days of the use of chromatography adsorbents and solvents were chosen largely by a process of trial and error. With its more extended use certain regularities have become apparent in the behaviour of particular adsorbents towards compounds related to one another but there is as yet no complete system of classification which makes it possible to predict the most suitable conditions €or any desired new separation.It is clear that the selective adsorption of one or more of the constituents of a solution depends on the relative affinities of the adsorbent and the solvent for the solutes. Thus solvents are chosen which have little or no affinity for the dissolved substances; they are usually non-polar in nature and may be typified by light petroleum and n-hexane. The adsor-bents are more or less polar and include aluminium oxide magnesium oxide silica sodium car-bonate and a great variety of other substances. Adsorption occurs at the more reactive groups in the molecules adsorbed for example at double bonds carboxy groups and hydroxy groups.Different crystalline modifications of a particular adsorbent may act in different ways but there is little precise information available to guide one in these variations. We may regard chromatographic adsorption as the result of a competition in attraction between the adsorbent and the solvent for the solute with accompanying dissolved substances influencing the degree of attraction. There seems to be little doubt that the contribution of each substance to the resultant affinity could be worked out on a quantitative basis but this is not yet possible and in many fields the basis remains qualitative or only very roughly quantitative at best. The earlier applications of chromatography in the analysis of fatty oils were made on the unsaponifiable constituents.Heilbron,l reviewing the adsorption of the carotenes and related substances on magnesium oxide notes that of the carotenes the y-isomer is most strongly adsorbed the p-isomer rather less strongly and the a-isomer least strongly. The varying alrfinity of magnesium oxide for these bodies is ascribed to their varying degrees of unsaturation and conjugation. Thus a-carotene with the least affinity for the adsorbent , has 10 double bonds out of I1 conjugated; /?-carotene contains 11 double bonds all conjugated; and 7-carotene the most strongly adsorbed contains 12 double bonds 11 of which are conjugated. The introduction of hydroxy groups into the carotenes does not alter the order in which they are adsorbed so that amongst the monohydroxy derivatives we find rubixanthin corre-sponding to y-carotene more strongly adsorbed than kryptoxanthin corresponding to p-carotene ; amongst the dihydroxy derivatives zeaxanthin corresponding to p-carotene is more strongly adsorbed than lutein corresponding to a-carotene.The hydroxy groups do however raise the general level of adsorption affinity mono-hydroxy-carotenes being more strongly adsorbed than carotenes and dihydroxy-carotenes more strongly than monohydroxy-carotenes. The affinity of magnesium oxide for xantho-phylls is so great that they can be adsorbed from ether solution whereas the carotenes cannot be adsorbed from so polar a solvent and the non-polar light petroleum has to be employed if they are to be picked up by the column. Increase in oxygen content in the absence of ester groupings progressively augments the adsorption affinity.Thus ast acene a prominent colouring matter of herring is adsorbed as a red-violet layer on aluminium oxide and cannot be eluted by means of methyl alcohol containing a trace of ether but requires the highly polar chloroform. Esterification of the xanthophylls reduces the strength of their adsorption nearly to that of the carotenes. Dealing more generally with the unsaponifiable matter of olive oil wheat germ oil and certain marine animal oils Drummond and his c o - w ~ r k e r s ~ ~ ~ ~ ~ dissolved the unsaponifiable matter in light petroleum and passed the solutions through aluminium oxide. They found that saturated hydrocarbons passed most readily through and that unsaturated hydrocarbons such as squalene and carotene passed through almost as easily.Unsaturated alcohols tended to be washed to the lower parts of the column the extent of their movement being influenced largely by the amount of squalene in the solution. A broad band of sterols appearcd about one-third of the way down the column and lipochromes of the xanthophyll type were found mixed with the sterols or in neighbouring zones. Saturated alcohols were usually at the to 260 WILLIAMS CHROMATOGRAPHY IK THE ANALYSIS OF FATTY OILS of the column. On re-fractionation of products removed from specific zones it was found that the relative order of adsorption might be changed alniost certainly owing to removal of the influence of co-solutes on thc first adsorption. Reference must next be made to the work of Walker and Mills,5 who dissolved linseed oil in n-hexane and passed the solution through aluminium oxide.The column was divided into equal portions and oil adsorbed on each was recovered and re-fractionated. It proved possible to separate the original oil quantitatively into fractions containing 7 6 5 and 4 double bonds per molecule and evidence was obtained of the presence of more highly unsaturated niolecules. Thus one fraction would contain mono-oleo di-linolenin and di-linoleo mono-linolenin both with 7 double bonds; a second would include mono-myristo- palmito- and stearo- di-linolenin tri-linolein and oleo-l'inoleo-linolenin all containing 6 double bonds ; and so on. The constituents of the oil were found to range themselves on the columns in descending order of unsaturation.This has a parallel to which attention may well be drawn in the catalytic hydrogenation of oils where there is a marked selective hydrogenation of the mure unsaturated fatty acids combined as esters before the less unsaturated ones react. Thus6 if linseed oil is hydrogenated with nickel catalyst at about 180" C. its linolenic acid is reduced almost completely to acids of lower iodine value by the time that the iodine value drops to 1120-130 and linolic acid disappears when the iodine value reaches about 50. The proportion of saturated acids does not rise to any marked extent until the linolenic acid has disappeared and the linolic acid has mostly been reduced. This parallel gives strong additional confirmation of adsorption on the catalytic metal as an essential stage in the hydrogenation reaction.Both on aluminium oxide and on magnesium oxide7g8 the more saturated acids are most strongly adsorbed from light petroleum; fair but not quantitative separation is achieved in one passage over the adsorber,t. Among the saturated higher fatty acids those of higher molecular weight are more strongly adsorbed. Mono-glycerides are more strongly adsorbed than di-glycerides and the latter more strongly than tri-glycerides as is to be expected from the increased polarity conferred by additional alcoholic groups. I t will thus be seen that in the absence of other polar groups increasing adsorption affinity arises from increasing unsaturation notably for hydrocarbons and esters. On the other hand the order is reversed for fatty acids and alcofids the more unsaturated compounds being less easily adsorbed.This reversal has been ascribed to the effect of a chemical aftinity of the adsorbent for acids but it is doubtful whether such an explanation could hold with alcohols and it is not supported by the failure of calcium carbonate to adsorb normal fatty acids from light petroleum. The reversals become understandable if we postulate the occurrence of polar charges of differing sign and we have an adsorbent capable of attracting polar material of either positive or negative charge; thus double bonds of negative charge would be attracted in order of iii-creasing unsaturation if they occur in molecules otherwise non-polar ; but if the molecules also include a terminal group of strong positive polarity such as a carboxy or hydroxy group and the operative affinity is a function of the algebraic sum of the various polarities in-creasing unsaturation could well lead to decreasing affinity.Absence of reversal of affinity gradation in passing from the carotenes to the xanthophylls differing by a hydroxy group, would be due to this group having a positive polarity numerically less than the negative polarity arising from the double bonds. It is interesting to note that reversal of the order in which related compounds are ad-sorbed may be brought about by changing the solvent. Thus dyes of the fluorescein series are adsorbed on aluminium oxide in order of increasing halogen content but the order is reversed if the solvent is 60% aqueous pyridine.We may assume that the oxide will attract most strongly the dye held least strongly by the solvent. Then if water has a small attrac-tion for the dye the order of adsorption would be expected to follow the halogen content. If on the other hand the solvent attracts the dyes strongly in order of increasing halogen content as might be expected with pyridine the adsorbent would remove from solution most easily the dye least strongly held by the solvent and the order of adsorption is reversed. Thus certain colouring matters found in fatty oils are positively charged and migrate to the negative pole on electrolysis. These colours are strongly adsorbed by fullers' earth which bears a negative charge. On the other hand negatively charged colouring matter found in sugars is not removed by the With fatty acids adsorption affinities are the reverse of those for fatty esters.It is known that electrical charges affect adsorption WILLIAMS CHROMATOGSAPHY I N THE ANALYSIS OF FATTY OILS 261 earth but is more readily attracted by carbon an adsorbent without natural charge. If a positive charge is given to the carbon its power of decolorising sugar is enhanced. The decolorising power of carbon towards oils is said to be reduced by addition of soluble acid to the oil as the positive ions of the acid then compete with the colouring matter for a place on the adsorbent. Results have been obtained in most of the analyses so far referred to by fractionation and re-fractionation on chromatographic columns ; such examinations are lengthy and can be attempted only in instances vjhere lengthy treatment is justified.Elaborate procedure is not required for a number of separations and simple chromatographic methods are available for use in commercial analysis leading to the removal and determination of a single con-stituent of a fat. (1) Free Fatty Acids-Sylvester Ainsworth and Hughesg pass an ether solution of a fat through a column of aluminium oxide; the free fatty acids are quantitatively removed by the adsorbent and the solvent is sufficiently polar to retain all other ether-soluble matter so that this may be recovered quantitatively by washing the column with ether and evaporating off the soivent. The nethod gives an extremely satisfactory separation and is likely to be used extmsively.It has obvious advantages over the usual method of titration with alkali, no assumption of molecular weight being involved; it is also preferable to extraction of the acids with aqueous-alcoholic alkali from light petroleum solution as this renders possible the inclusion of some giycerides of lower fatty acids with the free acids. The adsorption method also proves very satisfactory in the purification of the preliminary extract of unsaponifiable matter yielded by the S.P.A. method for the determination replacing the lengthy technique of washing with water and alkali in that method. The preferential adsorption of free fatty acids from mixtures with neutral fats has its parallel in the catalytic hydrogenatioE of such mixtures for which PellylO showed the free fatty acids to be preferentially hydrogenated by nickel catalyst.Here again there is con-firmation that adsorption is of major importance in catalysis. (2) Hydrocarbons-The passage of hydrocarbons through a column of aluminium oxide has been developed into a. very useful method for their determination. Fitelsonll concentrates squalene from olive and other oils by chromatographing a solution of the unsaponifiable matter in light petroleum through the oxide; the filtrate containing the squalene and any other hydrocarbon present is evaporated a d recovered operations being conducted in an inert atmosphere. Squalene may be identified by its crystalline hydrochloride and its proportion determined from the iodine value obtained by the Rosenmund-Kuhnhenn method. The presence of this hydrocarbon has been conclusively demonstrated in notable quantities in olive oil where it accounts for the high iodine value of the unsaponifiable matter wheat germ oil rice bran oil and many marine animal oils and in much smaller quantities in many other oils, Similar separations of hydrocarbons have been in use in my laboratory for some years for determining mineral oils in admixture with fatty oils and waxes.For example ad-ventitious hydrocarbons (mineral oil) can be thus determined in wool grease; the method may be ~ s e d for determining hydrocarbons in distilled fatty acids so as to assess the degree of degradation that has taken place during manufacture and in the determination of mineral oils in compoanded oils and in certain mixtures used in the leather industry containing sulphonated oils.(3) Carotem Xnntho$hylis and Vitamin A -Several met hods have been published dealing with the determination of these substances and two are chosen for their illustration of principles. Barton Mann,12 analysing the fat of egg yolk prepares the unsaponifiable matter and adsorbs it from light petroleum on bone meal previously defatted. Light petroleum elutes a- and ,%carotenes quantitatively from the column. Carotene and vitamin A are eluted quantitatively by means of a solution of 2% of chloroform in light petroleum this small propor-tion of chloroform being sufficient to overcome the affinity of the oxide for the vitamin. Sterols are also removed by the mixed solvent. Xanthophylls are removed from the column by acetone.This is a good illustration of the changes that can occur when eluting solvents are altered the effect being controlled by the polarity of the solvents. Cooley Christiansen and Schroeder chromatograph a light petroleum extract from feeding stuffs on sodium carbonate and thereby remove all chromogenic substances capable of interfering with the antimony trichloride test €or blue value.13 (4) Oxidised Acids-The methods so far described have dealt with the adsorption of Amongst these are the following 262 WILLIAMS CHROMATOGRAPHY IN THE ANALYSIS OF FATTY OILS substances completely in solution. There is a growing class in which adsorption is used to assist in the stripping of materials of low solubility from a solvent. The determination of oxidised fatty acids is an instance.These acids are characterised by their low solubility in light petrol and thus differ from the freely-soluble normal acids. The classic method for their determination consists in the preparation of the free fatty acids by saponification and their extraction with the solvent. A precipitate forms and after standing is filtered off washed, dried and weighed. Alternatively the washed precipitate may be extracted with ether, when a proportion will dissolve this proportion depending on the degree of oxidation. Ex-perience of the test makes it clear that the results are affected to a notable extent by the relative proportions of solvent and acids taken as the normal fatty acids have a solubilising effect; if the oxidised acids are present in small proportion they may be incompletely pre-cipitated.14 Recent work in my laboratory has shown that a more satisfactory determination may be made if the light petroleum solution filtered from the oxidised acid precipitate is passed through a column of calcium carbonate previously heated to about 200" C.for 2 hours. Washings from the precipitate are also passed through the filter which is further washed with light petroleum and then eluted with ether. The ether eluate is evaporated and the residue dried and weighed the weight being added to that of the precipitate. The material so separated appears to have a composition very similar to that of the main precipitate. All fatty acids passing the filter and caught on the column have so far been entirely ether-soluble. Calcium carbonate is used as adsorbent since in contradistinction to alumina it does not adsorb normal fatty axids from light petroleum.Typical results obtained by the method are shown in Table I. TABLE I Total oxidised acids found per cent. I Sample Classic method Adsorption method Arachis oil nil 0.40; 0.38 Sod oil . . 1.19 1.48; 1-47 Linseed oil (oxidised) . . 21-56 22.35; 22.38 The close relation between development of peroxide value and oxidised acids in fatty oils is similar to that noted in turbine lubricating 0ils.15 (5) Impurities in Sulphur Olive Oil-This oil contains impurities soluble in carbon disulphide and comparatively insoluble in light petroleum and of a resinous nature. It is known that as for oxidised acids the extent of their precipitation from light petroleum is influenced by the relative amounts of oil and solvent.Agreement had been reached in 1939 for the use of 50 times as much light petroleum as oil in the determination of the impurities there being evidence that further dilution caused no further precipitation. Attempts have now been made to remove higher amounts of impurity by chromatographic means. It was found that adsorption occurs when a mixture of the oil and light petroleum is passed through a column of calcium carbonate and that the resinous impurities thus adsorbed can be eluted by carbon disulphide. The amount recovered is identical within the limits of experimental error with that found by the agreed filtration method; and it is concluded that the agreed method is satisfactory.In a typical experiment 5 g. of a filtered sulphur olive oil were dissolved in 250 ml. of light petroleum and passed through calcium carbonate. A dark green band formed at the head of the column ; the column was washed with 200 ml. of light petroleum and eluted with carbon disulphide. After evaporation of the solvent and drying the residue amounted to 4-72% and in a duplicate test to 4.74%. Determination by the agreed method (5 g. of oil, dissolved in 250 ml. of light petroleum is allowed to stand for 30 min. and filtered through a paper previously dried and weighed in a bottle; the paper is washed well with cold light petroleum dried to constant weight at 105" and re-weighed in the bottle) gave 4.72%. SUMMARY-The application of chromatography in the analysis of fatty oils is briefly reviewed emphasis being laid on the principles involved.Methods are described for the determination of free fatty acids carotene xanthophylls and vitamin A hydrocarbons, oxidised acids and certain impurities of sulphur olive oil. No exhaustive summary of the literature has been attempted fuller accounts appearing in Paint Technology 1945 10 85 and 107. A quantitative basis needs to be established on which the relative affinities of solvents and adsorbents for solutes may rest. At present there is no clear indication where this i CROPPER SOME APPLICATIONS OF CHROMATOGRAPHIC ANALYSIS IN INDUSTRY 263 to be sought; it may lie in parachors di-pole data surface potentials or elsewhere. It seems certain that its discovery will be assisted by what we know of forces existing near the surface of liquids and at the irregular surface boundaries of solids the importance of whose fine cracks 1.2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 16. and projecting or partly isolated atoms is rapidly becoming-recognised. REFERENCES Heilbron I. M. J . SOC. Chew. Ind. 1937 56 1 6 0 ~ . Thorbjarnarson T. Ruiz A. Santos and Drummond J. C. ANALYST 1935 60 382. Thorbjarnarson T. and Drummond J. C. Id. 1935 60 23. Drummond J . C. Singer E. and Macwalter R. J. Biochem. J . 1935 29 466. Walker F. T. and Mills &I. R. J . SOC. Chem. Ind. 1942 61 125; 1943 62 106. Williams K. A. and Bolton E. R. ANALYST 49 460. Kaufmann H. P. Fette und Seifen 1939 46 268; 1940 47 460. Graff M. M. and Skau E. L. Ind.Eng. Chem. Anal. Ed. 1943 15 340. Sylvester N. D. Ainsworth A. N. and Hughes E. B. ANALYST 1945 70 295. Pelly R. G. J . SOG. Chem. Iwd. 1927 46 4 4 9 ~ . Fitelson J. J . Assoc. Ofl. Agv. Chenz. 1943 26 499 606. Mann A. Barton ANALYST 1943 68 233. Cooley M. L. Christiansen J. E. and Schroeder C. H. Ind. Eng. Chem. Anal. Ed. 1945 17 669. Dastur N. N. and Lea C. H. ANALYST 1941 66 90. Williams K. A. Id. 1945 70 409. 6 MILNER STREET LONDON S.W.3 Februavy 1946 Some Applications of Chromatographic Analysis in Industry BY F. R. CROPPER CHROMATOGRAPHIC analysis is a comparatively recent addition to the methods used by the industrial analyst for routine control testing and research purposes. The slowness with which chromatography was adopted was due partly to the fact that suitable adsorbents were expensive and had to be “recovered” for subsequent re-use and were then found as often as not to be of different adsorptive power.Merck’s Alumina “nach Brockmann” was the most popular adsorbent1; this was prepared by heating aluminium hydroxide to a strong red heat and then partially deactivating by shaking with moist air for short or long periods, as necessary to give reproducible activity. Difficulties arose after 1939 when supplies of Merck’s material ceased. In the Dyestuffs Division of Imperial Chemical Industries Ltd. this was overcome by preparing activated material by the process initiated by A. Stewart2; this process involves activation of alumina by heating to 360” C. to reduce the moisture content to lo% and deactivation of the product to any desired degree by adding a little water e g .1-50/, and then mixing thoroughly. The deactivated grades are of reproducible quality have a comparatively high adsorptive power and allow a fairly rapid rate of flow of solvent. A suitable activated alumina is obtainable from Peter Spence & Co. Ltd., Manchester under the name Type “ 0 ” Activated Alumina and the price is such that recovery by solvent extraction and reactivation is unnecessary. The activity of Merck’s Alumina was controlled by chromatographic trials using a solution of several Sudan co1ours.l The reproducibility of the Type “ 0 ” alumina and of the partially deactivated products may be controlled in an analogous way using a solution of three azo compounds namely azobenzene, benzene-azo-,G’-naphthol and p-dimethylaminoazobenzene ; a solution of these three colours in a mixture of chlorobenzene and light petroleum is added to the column which is developed with the same solvent mixture; azobenzene quickly descends the column and is soon washed through completely while benzene-azo-/%naphthol is held the most tightly.The position of the bands after washing with a known amount of solvent gives a semi-quantitative check on the adsorbent power. It does not follow of course that an alumina which is satisfactory for this separation will necessarily be the best for other types of separation. Chrorr,atographic analysis has been developed by A. Stewart* as a particularly valuable tool in the anthraquinone field. An example is provided by the analysis of technical 2-amino-anthraquinone using Type “ 0 ” alumina plus 5% of added water as adsorbent and a mixture of toluene and pyridine as solvent.The column is developed until the main zone is completely * Research Department I.C.I. Ltd. Dyestuffs Division 264 CROPPER SOME APPLICATIONS OF CHROMATOGRAPHIC ANALYSIS IN INDUSTRY eluted and the intensity of colour of the percolate is then measured on the Spekker absorptio-meter. The column exhibited at the Meeting was prepared deliberately from a mixture of crude 1-amino- and 2-an~ino-anthraquinones and was at a half-developed stage ; the percolate contained the 1-amino-isomer while the bands on the column corresponded to %amino-anthraquinone and 1 2-diamino- and 1 4-diamino-anthraquinones. In actual fact there is no 1-aminoanthraquinone in good quality technical 2-aminoanthraquinone.Quantitative analyses of many other coloured compounds are carried out in an analogous manner. In addition to control analyses of this kind chromatography has been used for identification purposes. A competitive dyestuff for example may be separated into its several fractions, each of which may be identified separately; in one instance hydrolysis of the dyestuff gave benzoic acid a dibasic acid and a coloured mixture which was resolved from benzene - acetone solution into 1 4-diaminoanthraquinone (violet zone) and 1 5-diaminoanthraquinone (orange zone) indicating that the original dyestuff was an amide derived from 1 mol. of dibasic acid with 1 mol. each of l-amino-4-benzoylaminoanthraquinone and 1-amino-5-benzoylamino-ant hraquinone.The chromatography of materials which are normally colourless in visible light usually necessitates the use of some alternative means of locating the zones; the easiest way when dealing with fluorescent compounds is to observe the column under an ultra-violet fluorescence lamp. This method was empl~yed,~ in conjunction with the ultra-violet absorption spectro-graph for the determination of anthracene in coal-tar and coal-tar distillates. The ultra-violet absorption spectrum of anthracene is highly characteristic with intense maxima at 360 w p and 380 trip in chlorobenzene solution. The spectra of tar oils show these two maxima, but their relative intensities indicate that other components of the oil also absorb ultra-violet radiation at these wavelengths thereby “ distorting ” the anthracene absorption curve.Separation of anthracene from these other components was effected by chromatography on alumina using a mixture of chlorobenzene and light petroleum as solvent The anthracene passes down the column fairly quickly leaving all the more complex polynuclear hydro-carbons higher in the tube In ordinary light only narrow yellow or brown zones are visible at the top of the column but in ultra-violet light several fluorescent zones appear”; the anthracene zone is located by its fluorescence in the lower third of the column the zone is removed mechanically from the tube and the anthracene is dissolyed out with hot chloro-benzene. The amount of anthracene in the solution was determined by its ultra-violet absorption intensity.The absorption curves of the components in the other zones of the column showed that the compounds responsible for “ distortion ” of the original anthracene curve were adsorbed more strongly. It is believed that this is the first time that reliable figures have been obtained for the anthracene content of tar (1%) and of pitch (0.4%) in contradistinction to the amount which can be isolated in the form of crude pastes by a process of fractional distillation and chilling. The activated alumina Type “ 0 ” is strongly alkaline and is quite unsuitable for use for materials which are unstable in presence of alkali or which contain acidic groups. An acid-washed alumina can be prepared by boiling Type “ 0 ” alumina with dilute acetic acid, filtering washing and again activating by heating to 360” C.; the product has a slightly acid reaction and its activity is rather less than that of the original Type “ 0 ” adsorbent.This material has been used4 by J. Raventost in biological studies on the breakdown products from thiobarbituric acids. The determination of barbituric acids and thiobarbituric acids in admixture was achieved by preparation of a chloroform extract of the biological fluid or tissue and separation by chromatography on acid-washed alumina ; the acids were held on the alumina while the pigment was washed out and the thiobarbituric acid was then eluted by chloroform containing 2% of methanol. The barbituric acid was ultimately eluted by chloroform containing 10% of methanol. Each eluate was then tested by an appropriate colour reaction which while satisfactory for a single component would not have been applicable to the original mixed barbituric acid and thiobarbituric acid extract.It was shown that thiobarbituric acids are excreted partially as the non-thio analogue. Magnesium carbonate “ Pond ” is strongly adsorbent for some types of compound and gives a satisfactory rate of flow of solvent. It has proved useful for chromatographic separations when alumina Adsorbents other than alumina have had a more limited application. * This column was demonstrated. t Research Department I.C.I. Ltd. Dyestuffs Division CROPPER SOME APPLICATIONS OF CHROMATOGRAPHIC ANALYSIS I N INDUSTRY 265 has not been permissible owing to formation of lakes as is the case with hydroxyanthra-quinone derivatives.H. E. Stagg* has used filter paper extensively as adsorbent in tests for the quality of dyestuffs intermediates. These paper chromatograms or capillary run-out tests are carried out on filter paper circles placed between two flat glass plates the upper of which has a central hole.5 A concentrate of the alleged impurities in the intermediate is diazotised and coapled or is coupled with a suitable diazo reagent and a drop of the coloured solution is then placed in the hole; to this is added water or other suitable solvent dropwise from a burette to develop the chromatogram. As the water or other solvent diffuses from the central hole the components of the mixture are carried in concentric rings towards the rim of the paper.The intensity of the impurity zones is then compared with a standard series of papers prepared in the same way from known synthetic mixtures. An alternative pro-cedure involves only the dipping of a paper strip into the coupled mixture and observation of the rise of the various components by capillary attraction. G-acid (P-naphthol-6 8-disulphonic acid) can be determined in R-acid (P-naphthol-3 6-disulphonic acid) by coupling with diazotised m-nitroaniline and running out on paper between glass plates; the range 0-40jd of G-acid may be covered with an accuracy of about 0.5 in the percentage figure. The standard series of paperst shows a gradual increase in the intensity of the yellow zone derived from G-acid as the concentration of this acid rises. Aniline when present as impurity in aminoazobenzene may be determined by diazotising and coupling with H-acid (l-amino-8-naphthol-3 6-disulphonic acid) and developing a paper chromatogram in the way described ; the intensity of the red zone is a sensitive measure of the aniline content.7 In the case of Tobias acid (/l-naphthylamine-l-sulphonic acid) a con-centrate is coupled run out on paper and developed until the outer zone due to the isomeric /3-naph thylamine-8-sulphonic acid (not normally present) is well separated from the main zone; the outer zone is cut out and extracted and the colour of the extract is measured by the Spekker absorptiometer. This account of chromatographic analysis in an industrial analytical laboratory is necessarily brief but sufficient will have been said to show that chromatography is certainly earning its rightful place as one of the most valuable weapons in the hands of theindustrial analyst.REFERENCES 1. 2. 3. 4. 5 . Brown Natatre 1939 143 377. Brockmann H. and Schodder H. Rer. 1941 74 73. Stewart A. and Imperial Chemical Industries Ltd. British Patent Specification No. 565,406. Cropper F. R. and Strafford N. J . SOC. Chem. Ind. 1944 63 268. Raventos J. Personal communication and Brit. J . Pharmacology and Chemotherapy (1946-in press). IMPERIAL CHEMICAL INDUSTRIES LTD. DYESTUFFS DIVISION ANALYTICAL LABORATORIES BLACKLEY MANCHESTER 9 DISCUSSION ON THE FOUR PRECEDING PAPERS The CHAIRMAN (Mr. R. C. Chirnside) said the papers read seemed to fit into each other very con-veniently to provide a basis for discussing the subject.Dr. F. R. CROPPER said it appeared from Mr. Williams's remarks on the chromatographic separation of the glycerides of linseed oil that the bulk of the glycerides contain 7 double bonds per molecule. Examination of the chromatographic fractions by the ultra-violet absorption spectrograph preferably after application of glycol saponification would show how this and other fractions were constituted as regards linolic and linolenic acids e.g. oleo-dilinolenin or dilinoleo-linolenin. Did Mr. Williams know if any work had been done on these lines ? There were chemical methods of dealing with the problem, but to obtain sufficient of the chromatographic fractions for such work took a very long time. For example, with linseed oil from 12 to 20 fractionations would be necessary in the first place to obtain sufficient material to fractionate in the second series and six or twelve months' work might be involved.Mr. M. R. MILLS endorsed what Mr. Williams had said about the length of time required for this type of work. For the separation of the component glycerides of linseed oil a long series of experiments were necessary to obtain fractions representing only one level of unsaturation. In an instance with which he was concerned the final products were not large enough for exhaustive examination and had been used for thiocyanogen value determinations. The next step was obviously to explore the fatty acid composition at the different levels of unsaturation so that the glyceride species present in each could be identified.It seemed probable that more recent developments of chromatographic technique as applied to fatty oils would simplify the separation and give larger yields thus opening up a wide field for future research. Mr. WILLIAMS said he knew of none. ~ * Analytical Department I.C.I. Ltd. Dyestuffs Division. t These papers were made available for detailed examination during the meeting 266 SYMPOSIUM ON CHROMATOGRAPHY DISCUSSION Mr. G. H. OSBORN asked whether inorganic substances had been found amenable to chromatographic separation. Mr. ROBINSON said he had mentioned as one such instance the separation of certain metals on a column of 8-hydroxyquinoline ; banding occurred with vanadium a t the top and then tungsten copper nickel and cobalt zinc iron and uranium.With other adsorbents the method could be used to separate potassium, sodium ’magnesium and calcium. Dr. SYNGE said that reading between the lines of the Smythe Report on atomic energy he thought some revelations might be looked for in the inorganic field. Mr. WILLIAMS mentioned that in a lecture before the Institute of Chemistry by A. H. Cook in 1941 reference was made to the separation of isotopes of lithium in columns about 30 feet in length. Dr. CECIL L. WILSON said he had had some experience of inorganic chromatography. There was a fundamental difference between the underlying processes of chromatographic separations of organic and inorganic substances. Although banding occurs with both classes it is impossible with inorganic substances t o get the clear separations with blanks between that are usually displayed by organic mixtures.Secondly, it is usually preferable to work with extraordinarily dilute solutions of inorganic ions. Inorganic separations had been found especially sensitive for the detection of very small amounts sometimes as little as 1 p.p.m. of one ion in presence of another. A very recent paper recommended the use of 8-hydroxyquinoline columns for routine qualitative separation of copper from cadmium but this required further trial. Dr. S. TORRANCE asked whether in inorganic ionic adsorption by special synthetic resins the adsorption occurred in a series of chromatic bands amenable to separation. Mr. ROBINSON said the adsorption occurred in bands and Amberlite I.R. 100 when used for adsorbing basic substances gave banding.Dr. CROPPER asked if there was a real gap between the bands which made it easy to separate them. Mr. ROBINSON said the bands were not separated by gaps as in the examples shown. Dr. SYNGE thought that these ion exchange reactions were more amenable to treatment by the displace-ment chromatography of Tiselius in which there was a procession of substances eluting one another as they passed down the column. Incidentally one often noticed that in ordinary organic chromatography in the early stages where the mixture was very crude and one substance displaced another sharp bands occurred near the top of the column due to substances that would never show up sharply if in the pure state. This displacement technique was particularly suitable for substances where the Freundlich index l/n was very sharply different from unity and the adsorption isotherm was curved as often with inorganic materials and then the band developed a very sharp front; if its tail could be chased along with a more strongly adsorbed substance a very sharp and pure fraction might be obtained although there was no space between the different substances.Dr. J. G. A. GRIFFITHS said that as a rapid sorting test for finding suitable adsorbents and eluants for chromatographic separations the filter paper in the technique in which a filter paper is placed between two glass plates one of which has a single perforation may be replaced by a thin layer of finely powdered adsorbent such as alumina bone-meal etc. As with the filter paper the chromatogram consists of a series of concentric circles round the hole in the glass plate.Dr. S. JUDD LEWIS asked if chromatography could succeed in the detection of tea-seed oil in olive oil, and/or in the differentiation of the natural colouring constituents of jams both of which were possible by absorp€ion spectrography. Mr. WILLIAMS said that he must pay a tribute to Dr. Judd Lewis’s spectroscopic method for detecting tea seed oil which was the first successful method to be used for that purpose. He had not had occasion to investigate the basis of the method fully. He suspected however that the difference between the spectro-grams of tea-seed oil and olive oil was not basic depending on the composition of the oils themselves but rather due to the presence of colouring matters or the like usually associated with one or the other.If that were so the test would not stand up any better than some others that have been proposed such as one based on fluorescence of tea-seed oil which it was later found possible to remove or to impart to olive oil also. On the subject of colours in jams Mr. Williams said he had no knowledge of any chromatographic work but i t seemed a problem likely to respond to chromatography. Mr. E. PAUL referred to the investigation of the colouring matter in cigarette tobacco. Part was easily dealt with in light petroleum solution but a large proportion was soluble in water and very difficult to adsorb except on charcoal; alumina would not hold it. Mr. WILLIAMS suggested that the water extract containing the colouring matter contained also large amounts of reducing sugars and these like other solutes might interfere with adsorption of colouring matters.Dr. T. C. J. OVENSTON said that explosives chemists like himself doubted whether alumina deserved the popularity it had gaiced as a chromatographic adsorbent. Some important advantages were offered by a less expensive commercial grade of silica gel. The instability of some substances when adsorbed on alumina had not been observed when this particular silica gel was used. He also asked if anyone else had ever obtained two bands from one homogeneous substance. This phenomenon had been observed after certain pre-washing treatments of the column when the water content of the adsorbent exceeded a critical value. In such circumstances an uneven water distribution was set up leading to irregular activity down the column and this probably accounted for the abnormality.Dr. CROPPER said he had tried silica on several occasions but had found it difficult to reproduce chroma-tograms owing to variation in particle size and for his purposes alumina had been more satisfactory; he did not wish however to deprecate a plea for the more extended use of silica. Mr. H. C. RAMPTON had had some experience on the analysis of hydrocarbon mixtures using silica gel, and he agreed with what had been said about article size; the smaller the particles the sharper the separation between the zones. As a petroleum technoyogist he was interested to know what was meant by “light petroleum ” Petroleum products were now more variable in quality than before the war. That of b.pt. 60-80” C. might contain aromatics and benzene would be liable to be adsorbed on the top part of a Iron could thus be detected in trace amounts in copper SYMPOSIUM ON CHROMATOGRAPHY DISCUSSION 267 chromatographic column. hexane would be preferable. copoeia which used to be called petroleum ether and which is free from aromatics. between 40” and 60” C. fatty oils small differences in composition would not matter. For chromatographic purposes he thought a pure hydrocarbon such as normal Mr. WILLIAMS said that by “light petroleum” was meant the “light petroleum” of the British Pharma-The grade used boils He did not know its precise composition but for his chromatographic work wit

ISSN:0003-2654    

DOI:10.1039/AN946710251b

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE.By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time.The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years.The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion.The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on.Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp.15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C.Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner.He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE.By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time.The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years.The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions.After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on.Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175).Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408.London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent.and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks.,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction

ISSN:0003-2654    

DOI:10.1039/AN9467100267

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE.By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time.The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years.The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion.The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on.Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp.15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction

ISSN:0003-2654    

DOI:10.1039/AN9467100278

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE.By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time.The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years.The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion.The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on.Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp.15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C.Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner.He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction

ISSN:0003-2654    

DOI:10.1039/AN9467100282

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction

ISSN:0003-2654    

DOI:10.1039/AN9467100287

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction

ISSN:0003-2654    

DOI:10.1039/AN9467100288

出版商:RSC    

年代:1946

数据来源: RSC

摘要:

426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents.It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate.There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international.The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively.Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited.The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation.Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE.By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years. The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr.Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion. The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies.Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on. Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time.The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice.Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction426 REVIEWS INKS : THEIR COMPOSITION AND MANUFACTURE. By C. AINSWORTH MITCHELL, D.Sc., F.I.C. Fourth Edition. Pp. xi + 408. London: Charles Grihn tt Co., Ltd. 1937. Price 12s. 6d. net. This, the fourth edition of the standard and, indeed, so far as the reviewer’s knowledge goes, the only text-book on the subject in the language, bridges L gap of 13 years.The author, pre-eminent in his particular sphere, needs little more introduction to the world of technical industry than he does in his official capicity to readers of THE ANALYST, while his reputation in forensic science in all that appertains to handwriting is international. The chemistry of ink, difficult as it is and at times not a little obscure, hcl- riot developed markedly in the interval since 1924; but what progress has been made is covered by Dr. Mitchell in this edition in a very thorough manner. He has found it necessary to enlarge his work to the extent of some 20 per cent. and, in addition, to rewrite a large portion.The arrangement of the book follows the lines of previous editions. After a comprehensive historical introduction, the work is divided into three sections dealing with writing inks, printing inks, and inks for miscellaneous purposes, respectively. Under Section 1 are considered the chemical nature and treatment of the various raw materials used for writing inks from lcmp black to galls, the composition of finished iron-gall, logwood, vanadium, aniline black, and coloured inks, as well as a comprehensive scheme €or the tech~ical examination of inks, handwriting specimens and the identification of forge:-ies. Section 2 deals with the manufacture and examination of printing inks. ,tnd Section 3 with the miscellaneous materials entering into the compositilxx of copying, marking, safety, sympathetic, typewriter inks and so on.Amongst new matter may be noted references to the use of lignone sulphni--,ites in connection with writing ink, a scheme for the identification of individual con- stituents in inks in the form of writing, and the application of filtered ultra-.& if )let light and of infra-red photography in the elucidation of those problems to which such methods are suited. The British Government Standard Specificatior:s for Writing Inks, revised in 1928, are included for the first time. The avaihble evidence upon the constitution of gallotannin is brought up to date and <tbly reviewed, and there is a Comprehensive list of British patents. It is as difficult to withhold admiration of the encyclopaedic scope cjf the matter and references in this book as it is of the erudition and industry displiiyed in its compilation. Practically nothing that comes to mind has escaped atterition, and it is with rather impish glee that the reviewer, after careful search, asserts that he finds no specific reference to the type of alkaline (ammoniacal) gallotannate- iron ink, said t o find favour in the United States, although the di-ammonium hydroxyferrigallate compound of Silbermann and Ozorovitz receives notice. Nor is there mention of that class of quick-drying writing fluids which depend for their efficiency upon partial destruction of the paper sizing by caustic alk 1.5 or sodium silicate. There is no evidence that lignone sulphonate inks have proved se-rious competitors to iron-gall writing inks (pp. 15 and 175). Apart from the unkttmwn quantity of permanence, the principal failing of this type lies in their liability to contain traces of free sulphurous acid to which suspicion attaches in connt-ction

ISSN:0003-2654    

DOI:10.1039/AN9467100289

出版商:RSC    

年代:1946

数据来源: RSC