BASF Coatings Japan Patents Paint Composition

October 23, 2013

 U.S. 8,536,274 B2
BASF Coatings Japan Ltd. has been granted a patent for a clear paint composition comprised of an acrylic copolymer comprised from 35%-50% weight caprolactone structural units, based on the resin solid fraction, a hydroxyl group number of from 200-340 mg KOH/g and a weight average molecular weight of from 5,000-15,000, and a non-yellowing type polyisocyanate compound, wherein the isocyanate group of the component is included in a proportion of from 0.5-2 equivalents per one equivalent of hydroxyl group of the component, and wherein the paint composition is hardened solely by baking, not hardening by ultraviolet radiation, such that the Young’s modulus of the hardened paint film obtained from the paint composition is not more than 1.5 GPa, the molecular weight of intercrosslinking of the cured coating film (Mc) is not more than 350 g/mol, and the glass transition temperature (Tg) of the hardened paint film is at least 65° C.