Patent ID: 6162514
Filing Date: 2000-12-19
Classification: B29B,B29C,B29K,B29L,B32B,C09K,Y10T

Abstract:
A molded article including thermotropic liquid crystal polymer material, said article formed by a process comprising the steps of:(a) providing a composite preform sheet, said preform sheet having, through its thickness, at least five distinct regions;outermost regions (i) formed of a porous polytetrafluoroethylene material having an inward-facing surface and an outward-facing surface,intermediate regions (ii) containing liquid crystal polymer material and polytetrafluoroethylene material, andan inner region (iii) formed of liquid crystal polymer only;said intermediate regions (ii) being regions formed by impregnation of liquid crystal polymer material into at least a portion of the pores of the inward-facing surface of each porous polytetrafluoroethylene material;(b) disposing said preform over a mold so as to form a closed cavity;(c) heating said preform to a temperature greater than the melt point of said liquid crystal polymer;(d) creating a differential gas pressure from one side of said preform to the other so as to cause said preform to deform and conform to the molding surfaces of said mold, and thereby forming a molded article having a non-planar shape;(e) cooling and removing said article from the mold.