ELECTRODEPOSITABLE FILM-FORMING COMPOSITIONS CAPABLE OF FORMING STRATIFIED FILMS, AND THEIR USE IN COMPACT PROCESSES

摘要

An electrodepositable film-forming composition is provided, comprising a resinous phase dispersed in an aqueous medium. The resinous phase comprises: (1) an ungelled active hydrogen-containing, cationic resin derived from a polyepoxide; (2) a cationic acrylic resin containing urethane functional groups; and (3) an at least partially blocked polyisocyanate curing agent. Also provided is a coated metal substrate comprising: A) a metal substrate having at least one coatable surface, and B) a cured coating layer deposited on at least one surface of the substrate and having a coating/air interface and a coating/substrate interface, wherein the cured coating layer is deposited from the electrodepositable film-forming composition described above. Further provided is a process for coating an electroconductive substrate, comprising electrophoretically depositing on the substrate the curable, electrodepositable coating composition described above.

主权项

1. An electrodepositable film-forming composition comprising a resinous phase dispersed in an aqueous medium, said resinous phase comprising:
(1) an ungelled active hydrogen-containing, cationic resin derived from a polyepoxide; (2) a cationic acrylic resin containing urethane functional groups; and (3) an at least partially blocked polyisocyanate curing agent, wherein the acrylic resin comprises a reaction product of a reaction mixture comprising: (i) an acrylic resin having functional groups that are reactive with amines and (ii) a urethane functional amine compound, wherein the urethane functional amine compound comprises a reaction product of a reaction mixture comprising (a) a polyamine having at least one primary amino group and at least one secondary amino group; and (b) a cyclic carbonate.