Rohm and Haas patents pigmented polymer

摘要

Rohm and Haas has received a patent for a polymer composition comprised of organic colorant particles; and polymer particles comprised of polymerized units of phosphorus acid monomer and having first phosphorus acid groups, wherein: i) the polymer particles are prepared by aqueous emulsion polymerization of the phosphorus acid monomer at a pH of less than 2, or ii) the polymer composition is comprised of a level of water soluble polymer having second phosphorus acid groups defined by ratios of equivalents of second phosphorus acid groups to equivalents of first phosphorus acid groups in the range of less than or equal to 1.5, wherein each of the polymer particles are multistage polymer particles comprised of a) a first polymer comprised of a polymerized unit of a multiethylenically unsaturated monomer, polymerized units of the phosphorus acid monomer, and the first phosphorus acid groups, wherein the first polymer has a glass transition temperature in the range of from -60° C to 35° C; and b) a second polymer having a glass transition temperature in the range of from -60° C to 35~(deg) C, wherein a weight percent of the first " phosphorus acid groups in the second polymer, based on a weight of the second polymer, is 10% weight or less of a, weight percent of the first phosphorus acid groups in the first polymer, based on a weight of the first polymer and wherein the average weight ratio of the first polymer to the second polymer is in the range of from 1:2 to 1:20.