Patent ID: 7479525

Claim:
An isocyanate adduct useful as an isocyanate crosslinking agent in solvent borne coating compositions, wherein said isocyanate adduct is a product obtained by the reaction of: (1) a gelled acrylic polymer with (2) an excess of polyisocyanate compounds, wherein said gelled acrylic polymer is dispersed in an organic liquid carrier, and consists essentially of: (i) a crosslinked core comprising polymerized ethylenically unsaturated monomers, wherein the core is not soluble in the organic liquid carrier, and (ii) linear stabilizer polymeric components chemically grafted to said core, wherein said linear stabilizer components have weight average molecular weights in the range of about 500-20,000 as determined by GPC (gel permeation chromatography) using polystyrene as standard, wherein: (a) said stabilizer components comprise polymerized ethylenically unsaturated monomers; (b) said stabilizer components are soluble in the organic liquid carrier; (c) the core (i), the stabilizer polymeric components (ii), or both (i) and (ii) contain isocyanate-reactive hydroxy and/or secondary amine functional groups attached thereto; and (d) the excess of polyisocyanate compounds are present in an amount so that the ratio of NCO to OH/NH groups ranges from 5:1 to 50:1.