| 摘要 |
PURPOSE:To manufacture a resin sheet, whose transparency and especially surface haze are low, at favorable stability, by combining extrusion molding, for which extrusion equipment preset under specific conditions is used, with specific water cooling conditions. CONSTITUTION:A thermoplastic resin pellet is fed to a compression part 16 with pressure while the same is melted and plasticized at a feed part 15 and compressed. Then the same is melted and kneaded evenly at a sheering part 17 and mixing is performed further at the mixing part 18 while residual stress is mitigated. Along with mitigation of residual sheering stress of the molten resin fed to a stress mitigation part 19 with pressure through the mixing part 18 unification in cooling of the molten resin is performed also and extruded through an extrusion die as a resin filmy material 38 is introduced into slits 31, 35 of an upper and lower stage water tanks 33, 36 where cooling water flows down and cooled effectively with the cooling water of a high flowing-down speed. After the same has been received by passing the same further through the cooling water in a water tank 37, predetermined heat treatment of the same is performed to complete molding of a resin sheet superior in transparency and glossiness. |
