| 摘要 |
PURPOSE:To enhance flat properties by stretching and thermally-fixing a film and thereafter controlling temp. and moisture content in a slow cooling stage. CONSTITUTION:After a polyamide film is biaxially stretched, it is thermally fixed so that the shrinkage factor in hot water at 100 deg.C is regulated to <=3% in the longitudinal direction and the lateral direction. Thereafter while continuously blowing humidified air at <=150 deg.C, this film is slowly cooled at the rate of <=80 deg.C/sec. Simultaneously humidity conditioning is performed for the film and the moisture content of the film is regulated to 0.5-2%. Thereafter the polyamide biaxially stretched film is produced by winding the said film. In such a way, generation of a curl, a sagging and a wrinkle, etc., due to moisture absorption is reduced in the humudity-conditioned film. |
