| 摘要 |
PROBLEM TO BE SOLVED: To enable high speed film making by preventing coiling around a touch roll at a high extrusion speed of not less than 50 m/min and breakage of a film during lateral stretch of the manufactured non-stretched resin sheet. SOLUTION: The manufacturing method of the non-stretched resin sheet is characterized in that when extruding a molten thermoplastic resin between a cooling roll and a touch roll to manufacture the non-stretched resin sheet, the surface of the touch roll is covered with a substance other than a metal, and the non-stretched resin sheet made by using two or more auxiliary cooling rolls arranged so that they contact the touch roll is used for stepwise biaxial stretching. COPYRIGHT: (C)2006,JPO&NCIPI |
