Patent ID: 6984693

Claim:
A two-stage cure coating composition comprising a binder and a crosslinking component, wherein said binder comprises (1) an acrylic polymer having weight average molecular weight of 3,000 to 50,000 and having in the range of 7.0 weight percent to 40.0 weight percent, based on the weight of the acrylic polymer, of hydroxyl moieties wherein 40.0 to 70.0 weight percent of the hydroxyl moieties are provided by hydroxy butyl acrylate and the remaining hydroxyl moieties are provided by fast reacting hydroxyl constituents selected from the group consisting of hydroxy ethyl acrylate, hydroxy ethyl methacrylate and any mixtures thereof and by slow reacting hydroxyl constituents selected from the group consisting of secondary hydroxyl containing hydroxy propyl acrylate and secondary hydroxyl containing hydroxy propyl methacrylate and any mixtures thereof; and (2) the binder further comprises in the range of 1 to 20 percent by weight, based on the weight of the binder, of at least one acrylic oligomer having a weight average molecular weight in the range of 100 to 3,000, a polydispersity of 1.01 to 1.7 and one or more reactive functionalities reactive with isocyanate groups and said crosslinking component comprises an organic polyisocyanate having at least two reactive isocyanate groups and wherein the first stage curing of a finish of the composition on a substrate forms a water spot free finish within 90 minutes of application and wherein the composition has a pot life, measured at 25° C. on a composition having 38% solids of binder and crosslinking component, of less than a 2 second rise in Zahn cup viscosity in 150 minutes.