U.S. 8,114,920 B2
Akzo Nobel Coatings International B.V. has been granted a patent for  UV-curable aqueous emulsion comprised of a urethane reaction product of 1% to 10% by weight of a polycarbonate polyol or polyester polyol, 1% to 10% by weight of an isocyanate compound, 0.1% to 5% by weight of a reactive carboxylic acid, 1% to 10% by weight of a UV-curable acrylic oligomer having 2 to 9 functional acrylate groups and 5% to 20% by weight of a UV-curable acrylic monomer; and 0.1% to 20% by weight of a urethane-reactive acrylate, 0.01% to 1% by weight of a radical polymerization inhibitor and 55% to 75% by weight of water, based on the total weight of the UV-curable aqueous emulsion, wherein the UV-curable acrylic oligomer is a mixture of an oligomer having 4 or more functional acrylate groups and an oligomer having 3 or less functional acrylate groups, and wherein the UV-curable acrylic monomer is selected from the group consisting of trimethylolpropane triacrylate (TMPTA), tripropyleneglycol diacrylate (TPGDA), 1,6-hexamethylenediol diacrylate (HDDA), 1,4-butanediol diacrylate (1,4-BDDA), 1,3-isobutanediol diacrylate, isobonyl acrylate (IBOA) and a mixture thereof.