Patent ID: 6444749
Filing Date: 2002-09-03
Classification: C08F

Abstract:
An aqueous dispersion of polymer particles having a functional group for cross-linking, is obtained by a free radical emulsion polymerization of at least two different ethylenically unsaturated monomers, a surfactant of the formula M+.âˆ’OOCâ€”CH&boxH;CHCOOR, wherein R is C(6-22) alkyl and M+ is Na+, K+, Li+, NH4+, or a protonated or quaternary amine, and a co-reactive compound having at least two groups capable of reacting with the functional group for cross-linking, wherein the glass transition temperature (Tg) of the polymer at the center of the particle is different from the Tg of the polymer at the surface of the particle, the difference being at least 55Â° C., and the Tg of the polymer having the highest Tg is at least 40Â° C.