Patent ID: 7897676

Claim:
A process for producing a coating on a substrate, said process comprises: a) mixing a crosslinkable and crosslinking components of a coating composition to form a potmix, wherein said crosslinkable component comprises: a copolymer having on an average 2 to 25 crosslinkable groups selected from the group consisting of hydroxyl, acetoacetoxy, and a combination thereof; a weight average molecular weight ranging from about 1000 to 4500; a polydispersity ranging from about 1.05 to 2.5; wherein said copolymer is polymerized from a monomer mixture comprising one or more non-functional acrylate monomers and one or more functional methacrylate monomers provided with said functional groups, wherein said functional methacrylate monomers are present in an effective amount for producing said copolymer having on an average 2 to 25 crosslinkable groups and having said weight average molecular weight; wherein said copolymer is produced by free radical polymerization of said monomer mixture at a polymerization temperature ranging from about 120° C. to 300° C.; and wherein said crosslinking component for said crosslinkable groups is selected from the group consisting of polyisocyanate, polyamine, ketimine, melamine, and a combination thereof; and wherein said monomer mixture includes 100% to 80% of the total amount of the non-functional acrylate monomers and the functional methacrylate monomers, percentage being in weight percentage based on the weight of the monomer mixture; b) applying a layer of said potmix on said substrate; and c) curing said layer into said coating on said substrate.