Patent ID: 6166150
Filing Date: 2000-12-26
Classification: C08F,C08G,C09D

Abstract:
A multistage process for preparing an aqueous binder dispersion (BM) comprising an acrylate-modified polyurethane-alkyd resin (A'), the process comprising:(I) preparing a polyurethane alkyd resin (A) comprising:(a) from 5 to 50% by weight of a mixture comprising:(a1) from 90 to 30 parts by weight of an unsaturated C6 to C30 fatty acid having at least two nonconjugated double bonds, and(a2) from 10 to 70 parts by weight of an unsaturated C6 to C30 fatty acid having at least two conjugated double bonds,as esterified polymer side chains of the polyurethane-alkyd resin component (A), and(b) from 95 to 50% by weight of polyurethane units with monomer building blocks having anionic groups and/or groups which can be converted by neutralization into anionic groups, as polymer main chains of the polyurethane-alkyd resin component (A),(II) neutralizing the amionic groups and/or groups which can be converted into anionic groups and converting the polyurethane-alkyd resin component (A) into an aqueous dispersion or solution, and(III) polymerizing at least one ethylenically unsaturated, free-radically polymerizable monomer (c) which has essentially no reactive functional groups other than the C--C double bond, in the aqueous dispersion or solution of stage (II) in the presence of a free-radical polymerization initiator.