Patent ID: 8299183

Claim:
A polymer dispersion comprising: a) a dispersed polymer consisting of monomer units originating from one or more monomers (m), and, b) a polymeric stabiliser (C) which is a graft copolymer resulting from reaction of: i) a polymer (B) of a monomer mixture comprising monomers selected from the group consisting of one monomer (x) having a primary, secondary or tertiary amine or amide group and at least one olefinic unsaturation, and, a cationic monomer (y) having at least one olefinic unsaturation, if a monomer having an amide group is used, the polymer has been hydrolysed to convert the amide functionality into an amine functionality, and, ii) said one or more monomers (m), polymer (B) constituting the backbone of the polymeric stabiliser (C), and monomers (m) the grafted branches, and, c) a polymeric cationic co-stabiliser (A) being a homo- or co-polymer consisting of monomers m 2 of general formula (II), wherein the monomers, (m), consist of a non-ionic monomer, (m 1 ), and a cationic monomer, (m 2 ), wherein the non-ionic monomer, (m 1 ), is N-t-butylacrylamide, N-t-butylmethacrylamide or a monomer of the general formula (I): wherein R 1 is hydrogen or methyl, and R 2 and R 3 are, independently from each other, any of hydrogen, C 1 -C 2 alkyl, isopropyl, methylol, hydroxyethyl, or hydroxypropyl; wherein the cationic monomer, (m 2 ), is a monomer of the general formula (II): wherein R 4 is hydrogen or methyl, R 5 , R 6 and R 7 are, independently from each other, any of hydrogen, C 1 -C 8 alkyl or benzyl, D is oxygen or NH, E is C 2 -C 4 alkyl or C 2 -C 4 hydroxyalkyl, X − is an anionic counterion; and wherein the amine or amide monomer (x) selected from the group consisting of diallylamine, methdiallylamine, diallylpropanolamine, N-vinylformamide, N-methyl-N-vinylformamide, and N-methyl-N-vinylacetamide.