Patent ID: 7338574

Claim:
A process for making a multilayer composite comprising (A) providing a uniform dispersion in a liquid medium the dispersion comprising particles of a fluoropolymer having a fusing temperature, (B) depositing the dispersion onto a carrier web of a material that is thermally stable above the fusing temperature, (C) heating the carrier web coated with the dispersion to a temperature above a temperature effective to remove the liquid medium for a duration effective to remove the liquid medium and to a temperature above the fusing temperature to form a continuous, uniform thickness, protective layer of fluoropolymer film on the carrier web of which the protective layer has an inboard face adjacent to the web and an outboard face opposite the carrier web, (D) optionally applying additional dispersion onto the outboard face and heating the web and dispersion to a temperature above the fusing temperature for a duration effective to remove additional liquid medium and to build up thickness of the film of the protective layer, (E) optionally repeating step (D) until the protective layer is a preselected thickness, (F) treating the protective layer such that the outboard face is bondable to a polymer free of fluoropolymer, (G) while maintaining the inboard face of the protective layer in contact with the carrier web, applying to the outboard face a second polymeric layer of a composition substantially free of fluoropolymer, (H) bonding the second polymeric layer to the outboard face of the protective layer, thereby forming a multilayer composite of the protective layer bonded to the second polymeric layer, (I) adding to the second polymeric layer a reinforcement layer of a film, woven fabric, nonwoven fabric or combination thereof, and (J) peeling the multilayer composite from the carrier web.