| 摘要 |
PROBLEM TO BE SOLVED: To obtain a film, having no wrinkle, and excellent flatness, by a method wherein the film is passed on a winding roll, a pre-cooling roll and a plurality of heating rolls respectively immediately after orienting the film. SOLUTION: A film is passed on a winding roll 1 immediately after orienting the same and, thereafter, is passed on a pre-cooling roll 2. Further, the film is cooled gradually while passing through three sets of heating rolls 3. The surface temperature of the winding roll is preferable to be 50-150 deg.C and the wrinkles of the film, contacted with the winding roll, are extended. Further, in order to develop the extending effect of wrinkles, the pre-cooling roll 2 is arranged so that the winding angle between the film and the roll can be specified so as to be larger than 180 deg.C. The diameter of the winding roll is designed so as to be preferably 50-150mm so that a contacting period of time between the film and the roll becomes 3-10sec. On the other hand, the temperature of the pre-cooling roll is preferable to be 30-100 deg.C. The temperature of the heating rolls are preferable to be 100 deg.C in the first roll, 60 deg.C in the second roll and 30 deg.C in the third roll. |
