Patent ID: 6204319
Filing Date: 2001-03-20
Classification: C01P,C08J,C09C,C09D

Abstract:
An aqueous coating composition comprising:(a) an aqueous carrier medium:(b) a pigment having a pH below 7.0;(c) an AB block copolymer pigment dispersant resin consisting of(1) an A block comprising a hydrophobic polymer having amine groups; and(2) a B block comprising a hydrophilic polymer having hydroxyl groups and carboxyl groups;the AB block copolymer having a number average molecular weight of 5,000-20,000 and consists of 20-80% by weight of a polymeric A segment and correspondingly 80-20% by weight of a polymeric B segment;wherein the pigment to dispersant weight ratio is 0.1/1 to 20/1;(d) a film forming polymeric binder containing carboxyl groups and(e) a crosslinking agent which on curing of the coating composition will react with the carboxyl and hydroxyl groups of the AB block copolymer and the carboxyl groups of the film forming polymeric binder.