Patent ID: 6462125
Filing Date: 2002-10-08
Classification: C09B,C09D

Abstract:
A pigment dispersion comprising:(a) pigment; (b) an aqueous carrier selected from water and a mixture of water and at least one organic solvent; and (c) a pigment dispersant prepared by atom transfer radical polymerization initiated in the presence of a monomeric initiator, said initiator being one or more selected from the group consisting of linear aliphatic compounds, branched aliphatic compounds, cycloaliphatic compounds, aromatic compounds, polycyclic aromatic compounds, heterocyclic compounds, sulfonyl compounds, sulfenyl compounds, esters of carboxylic acids, nitriles, ketones and phosphonates, each having a single radically transferable group, and in which said pigment dispersant has the following representative polymer chain structure, &phgr;â€”(G)pâ€”(E)sâ€”T wherein G is a residue of at least one hydrophobic radically polymerizable ethylenically unsaturated monomer; E is a hydrophilic residue of at least one radically polymerizable ethylenically unsaturated monomer; G and E being different from one another; &phgr; is a hydrophobic residue of or derived from said initiator, and is free of said radically transferable group; T is or is derived from said radically transferable group of said initiator; p and s represent average numbers of residues occurring in a block of residues; p and s each are at least 1 and are each individually selected such that said pigment dispersant has a number average molecular weight of at least 250.