MANUFACTURE OF DOUBLE-SIDE EMBOSSED POLYCARBONATE SHEET

摘要

PURPOSE:To form recessed and projected patterns uniformly on both surface and rear face and manufacture products of various kinds of thickness efficiently by controlling the temperature of respective embossing rolls and the temperature of a polycarbonate sheet just after extrusion and just before the introduction into a second embossing roll. CONSTITUTION:The temperature of a first embossing roll 12 is set at 140-150 deg.C and the temperature of a second embossing roll 13 is set at 160-190 deg.C. Polycarbonate resin is extruded out of a die 16 of an extruder in a manner of setting the temperature of a polycarbonate sheet 14 just after the extrusion is set at 250-270 deg.C. Before the polycarbonate sheet 14 is introduced into the second embossing roll 13, the polycarbonate sheet 14 is heated so that the surface temperature on the side of the other face 14b is set at 190-210 deg.C at an emboss starting section in the process of embossing by the second embossing roll 13. As a result, excellent recessed and projected patterns are formed efficiently on both faces of the polycarbonate sheet 14.