CATIONIC ALIPHATIC POLYESTER RESINS AND THEIR USE IN ELECTRODEPOSITION

摘要

The present invention is directed to an electrodepositable composition of a resinous phase dispersed in an aqueous medium. The resinous phase includes a n ionic polyester polymer prepared from a) an aromatic and/or cycloaliphatic carboxylic acid compound having at least two aromatic and/or secondary aliphatic carboxyl groups, b) a branched aliphatic, cycloaliphatic or araliphatic compound containing at least two aliphatic hydroxyl groups, the aliphatic hydroxyl groups being either secondary or tertiary hydroxyl groups or primary hydroxyl groups attached to a carbon adjacent to a tertiary or quaternary carbon, c) a compound including an ionic salt group or a group which is converted to an ionic salt group, and d) optionally, at least one hydroxyl substituted carboxylic compound comprising at least one tertiary aliphatic carboxyl group and at least two aliphatic hydroxyl groups. The present invention also includes a method for electrocoating a conductive substrate with the described electrodepositable composition. Lastly, the present invention is directed to a conductive substrate coated according to the described method.