AbstractThis paper looks at newly developed trimethylolpropane (TMP) esters, which have multifunctional properties as additives in aqueous metalworking fluids. Such TMP esters can replace the previous monofunctional esters, which provided only lubrication.New TMP esters are obtained by chemical modification of traditional TMP esters, and provide the functions of lubrication, corrosion protection, and co‐emulsification in one product. The paper looks at the chemistry of these esters, and their properties. Some experimental products are also examine