Patent ID: 6270863
Filing Date: 2001-08-07
Classification: B29C,C09K,Y10T

Abstract:
A substrate for a liquid crystal display comprising a) a high quality plastic sheet produced by the method comprising the steps:a) providing molten plastic resin;b) directing the molten plastic resin to an overflow die having an inlet and an outlet;c) shaping the molten plastic resin into a molten web using said overflow die;d) guiding said molten web away from said overflow die; ande) cooling said molten web to form a solid sheet;wherein the molten plastic resin is a polycarbonate containing as bisphenol components: (1) 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; (2) a mixture of 2,2-bis(4-hydroxyphenyl)propane and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane; a blend of (1) and (2); or a blend of (1) or (2) with a second polycarbonate containing as a bisphenol component 2,2-bis(4-hydrozyphenyl)propane;and b) a conductive layer disposed on at least one side of the sheet, wherein the high quality plastic sheet has a sheet waviness value of less than or equal to 2.0 .mu., a birefringence of less than or equal to 0.0002, a thickness variation of 10% or less and a surface roughness of less than or equal to 50 nm over a 0.4 mm length.