MANUFACTURE OF TRANSPARENT RESIN SHEET

摘要

PROBLEM TO BE SOLVED: To manufacture a transparent resin sheet reduced in phase difference irregularity, having stable optical characteristics and low in residual phase difference. SOLUTION: A transparent resin sheet is produced by a process wherein a cyclic olefenic resin R is melted in an extruder to be extruded in a sheet form from the die 15 attached to the extruder and this sheet like cyclic olefinic resin sheet is brought into close contact with a cooling roll 20 of which the surface is subjected to mirror surface processing in a molten state to be molded and the obtained resin sheet 3 is taken over by a taking-over roll 40. The taking-over roll 40 is controlled so that the tensile force acting on the resin sheet S becomes constant within a range of±10% between the cooling roll 20 and the taking-over roll 40. In this method, the tensile force acting on the resin sheet S is pref. 20 kg/cm2 or less.