Patent ID: 7488841

Claim:
A method of producing an acyl group-containing composition containing at least one acyl compound represented by the general formula (2) comprising a step of reacting a long chain N-acyl acidic amino acid anhydride represented by the following formula (1): [Formula 1] wherein R 1 CO represents a long chain acyl group derived from a saturated or unsaturated fatty acid with 2 to 20 carbon atoms; R 2 is hydrogen or a lower alkyl group with 1 to 3 carbon atoms which is optionally substituted with a hydroxyl or carboxyl group; j, k are independently any of 0, 1 and 2 and are not 0 at the same time, with one or more compounds having, per molecule, m functional groups of one kind or more selected from the group consisting of hydroxyl, amino and thiol groups in an aqueous solvent and/or a mixed solvent of water and an organic solvent, wherein the acyl group-containing composition comprises at least one acyl compound represented by the following general formula (2): [Formula 2] wherein R 1 CO, R 2 , and j, k each represent the same as those defined in the above formula (1); n (n is an integer of 2 to 20, including 2 and 20) Zs are bonding portions to which m (m≧n) functional groups of one kind or more selected from the group consisting of hydroxyl, amino and thiol groups substituted on X bind and which are selected independently from the group consisting of —O—, —NR 3 — (R 3 is hydrogen, or an alkyl, an alkenyl, an aryl or an alkylaryl group with 1 to 10 carbon atoms) and —S—; X is a spacer of a straight, branched or cyclic hydrocarbon chain of molecular weight of 1,000,000 or less which optionally has substituents other than hydroxyl, amino and thiol groups and contains or does not contain an aromatic hydrocarbon; n substituents represented by the following general formula (3): [Formula 3] wherein reference characters each represent the same as those defined in the above formula (2), which are attached to X via Z are independent of each other; and Y represents a carboxyl group or the salt thereof.