Patent ID: 6037414
Filing Date: 2000-03-14
Classification: C01P,C08G,C09C

Abstract:
A polymeric pigment dispersant comprising a graft polymer having an acrylic polymer backbone and pending from the backbone, polyester side chains, cyclic imide groups and quaternary ammonium groups and the polymer having a calculated number average molecular weight of 8,000-50,000; wherein the graft copolymer consists essentially of(a) 10-50%, by weight of the of the graft polymer, of an acrylic copolymer backbone having a number average molecular weight of 2,500-10,000 which, before reaction, contains 25-75% by weight of polymerized oxirane containing monomers;(b) 20-85%, by weight of the graft polymer, of a polyester copolymer, or mixture of different polyester copolymers, having a number average molecular weight of 500-10,000 which polyester copolymer is carboxylic-acid functional and attached to the backbone by a reaction of the carboxylic acid functional groups with oxirane groups of the backbone;(c) 1-16%, by weight of the graft polymer, of cyclic imide groups attached to the backbone by a reaction on the imide groups with the oxirane groups of the backbone and(d) 0.2-17%, by weight of the graft polymer, of quaternary ammonium groups.