Patent ID: 6462163
Filing Date: 2002-10-08
Classification: C08G,C09J,H01L,Y10S,Y10T

Abstract:
A urethane laminating adhesive composition for forming a high barrier adhesive, the composition comprising a solventless liquid mixture of:either (I) (a) a hydroxyl-terminated polyester A), in molten form, said polyester A) formed from a single species of a linear aliphatic diol having from 2 to 10 carbons and a single species of a linear dicarboxylic acid, said polyester A) having a number average molecular weight from about 300 to about 5000 and a melting point of 80Â° C. or below, and (b) a single species of diisocyanate B); or (II) (x) a urethane prepolymer C) which is the reaction product of all of or a portion Bâ€²) of said diisocyanate B) with a portion Aâ€²) of said polyester A) at an NCO/OH ratio of between about 2 and about 8, (y) the remaining portion Aâ€³) of polyester A), and (z) any remaining portion Bâ€³) of diisocyanate B), in either case (I) or (II), the NCO/OH ratio of said diisocyanate B) to said polyester A) being between about 1 and about 1.1; andwherein the polyester A) is reacted with diisocyanate B) just prior to or upon application to a substrate, or the prepolymer C is formed and reacted with the remaining diisocyanate Bâ€³) and polyester Aâ€³) just prior to or upon application to a substrate, under conditions such that polyester crystalline domains form in the composition before substantial curing occurs.