a durability enhancing agent comprising the reaction product of an acrylic oligomer or acrylic polymer and an ultraviolet light absorbing compound , a hindered amine light stabilizer or mixture thereof , said durability enhancing agent further comprising more than one carbamate functional group , or group convertible to a carbamate group , and optionally , including other reactive functionality capable of undergoing a crosslinking reaction . also included is a curable coating composition comprising the durability enhancing agent , a method for obtaining a coated substrate and the coated article obtained thereby .