Patent ID: 6159404
Filing Date: 2000-12-12
Classification: C09D

Abstract:
A process for the low-temperature extrusion coating of a substrate with a polyethylene film having a thickness of at least about 0.0075 mm, said process comprising applying a composition to at least one surface of said substrate by extrusion coating at a temperature in the range of 175.degree. up to 290.degree. C. said composition comprising:(a) a polyethylene component having a melt index in the range of about 10 up to 100 dg per minute at 190.degree. C. and having a sufficiently broad molecular weight distribution so that the resulting composition is capable of being extrusion coated at a temperature in the range of 175.degree. C. up to 290.degree. C.,(b) in the range of about 0.5 up to 15 weight percent, based on the weight of the total of (a) plus (b), of a hydrocarbon tackifying resin having a RBSP in the range of about 90.degree. up to 150.degree. C., and(c) at least one thermally sensitive additive that is not sensitive at a point within the range of 175.degree. to 190.degree. C. at relatively high loadings of additives that contain a sufficient amount of volatiles that create unsatisfactory imperfections at relatively high temperatures, and a concentration in excess of about 10 weight percent based on the total wherein said thermally sensitive additive is a hygroscopic or hydrophilic additive.