二軸逐次延伸フィルムにおけるボーイング現象の解析―ボーイングひずみの低減策の検討―
Analysis of Bowing Phenomenon in Successive Stretching of Biaxially Oriented Film-Reduction of Bowing Distortion-
野々村千里・山田敏郎
Nonomura, Chisato / Yamada, Toshiro
In order to reduce the bowing distortion which occurs in the tentering process of film-making, the effect of the processing condition was examined. The following results were obtained for poly (ethylene terephthalate) film.
(1) Cooling the film below its glass transition temperature after stretching it in transverse direction greatly reduces the bowing distortion. The extent of reduction increases with the length of the cooling zone.
(2) Once the film was cooled after stretching, the bowing distortion is almost independent of the thermosetting temperature between 200℃ and 250℃.
Key words: Bowing phenomenon / Transverse stretching / Tenter / Thermosetting / Poly (ethytene terephthalate) film