Water-dilutable polyester, process for the preparation thereof and the use thereof

摘要

A water dilutable polyester having a good resistance to hydrolysis based on (A) at least one dicarboxylic acid unit, (B) at least one polycarboxylic monoanhydride and (C) at least one alcohol component containing at least dihydric alcohol, the COOH groups of the polyester being at least partially present in the form of salts with amine, characterized in that the polyester is also derived from (D) at least one epoxy compound which contains at least two oxiran rings and is selected from the group consisting of epoxidized fatty acids, derivatives thereof and epoxidized aliphatic hydrocarbons or mixtures thereof with up to 30% of monoepoxides, the percentage being based on the epoxy groups, and in that the polycarboxylic monoanhydride (B) is incorporated in the form of a half ester and is other than phthalic anhydride and maleic anhydride. The invention also relates to a process for the preparation of such polyester, its use in a coating composition and to articles coated with such coating compositions.