08.10.05
Air Products and Chemicals, Allentown, PA, has been awarded a U.S. patent covering a two component polyurethane-polyurea dispersion that is substantially solvent-free. It is prepared from (a) an aqueous mixture of an acid containing polymeric polyol and polyol free of acid groups, wherein the mixture has an average hydroxyl functionality of at least 1.5 and an acid number between 15-200; and an amine or a blend of amines having an average active hydrogen functionality of at least 1.5, the amine or blend being present in a sufficient amount to substantially neutralize the acid-containing polymeric polyol; (b) one or more polyisocyanates; and (c) two or more different pigments. The improvement for reducing or eliminating flooding of the pigments is comprised of (d) an aqueous polymer emulsion comprising a polymer prepared by aqueous emulsion free radical polymerization, the polymer emulsion present in an amount sufficient to impart thixotropy to a mix