METHOD OF MANUFACTURING STRETCHED FILM, DEVICE FOR MANUFACTURING STRETCHED FILM AND SYSTEM FOR MANUFACTURING STRETCHED FILM

摘要

A film (F) is transported with one end side in a width direction moved relatively in a preceding manner and the other end side moved relatively in a delayed manner and thus the film (F) is stretched in an oblique direction with respect to the width direction. In the individual positions of the film (F) in the width direction, the film (F) is asymmetrically heated in the width direction such that the amount of displacement (ΔL) of an orientation angle from a desired angle caused by bowing (Bo) asymmetrically produced in the width direction by the stretching of the film (F) in the oblique direction is reduced, and thus a maximum value in the temperature distribution of the film (F) is present between a center portion in the width direction and any one of end portions.

主权项

1. A method of manufacturing a stretched film, the method comprising:
an oblique stretching step of transporting a film with one end side in a width direction moved relatively in a preceding manner and the other end side moved relatively in a delayed manner so as to stretch the film in an oblique direction with respect to the width direction, wherein the method of manufacturing a stretched film includes a step of heating the film in the width direction such that a temperature distribution is asymmetrical with respect to a center line in the width direction and that bowing produced asymmetrically in the width direction by stretching the film in the oblique direction is reduced, and the heating is performed such that a position where a temperature in the temperature distribution in the width direction of the film at a time of the heating is maximized is present between a center portion in the width direction and any one of end portions.