| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a producing method for a synthetic resin film, in which in such a method for producing a film that a thermoplastic resin is extruded in a film state from a mold 3 and the film is received by receiving rolls 4 and both end parts of a width are trimmed and thereafter the film is wound and scraps generated by trimming are crushed by a grinder 7 and thereafter returned to an extruder as a recycled raw material. Even if fluctuation of the generated amount of the film scrapped by trimming is caused, the film of constant quality can be produced by favorably controlling fluctuation of extrusion and fluctuation of thickness. SOLUTION: The velocity of the screw 11 of an extruder is regulated in correspondence with the generated amount of a recycled raw material so that the volume ratio of a pure raw material charged to the extruder and the recycled raw material is made constant. Receiving velocity is regulated in correspondence with regulation of velocity of the screw.</p> |
