摘要:
In a multistage tenter with the right and left clip chains for conveying a belt-shaped film in a drying unit, a tensing mechanism operates to slide the supports of a pair of right and left sprockets engaged with the clip chains to tension the latter simultaneously, so that the shorter of the two clip chains is automatically tensioned more than the other, whereby the pitch error of the clip chains is absorbed, and the film is accordingly prevented from being wrinkled while being conveyed.
摘要:
A PVA film successively oriented in two orthogonal directions is prepared by firstly elongating the film in the longitudinal direction by more than 200% while maintaining the water content (Z .times. 100)% at a value of from 10 to 35% and the temperature in a range of from (1.50/Z +20).degree. C to 75.degree. C. The film is then preheated while maintaining its water content at least 7%, and then elongated laterally by more than 200% at a temperature of from 45.degree. to 110.degree. C. Then the film is heat treated at a temperature of 110.degree. to 210.degree. C while permitting the film to shrink by less than 15% in the lateral direction. Finally, the film is cooled to room temperature under tension.
摘要翻译:通过首先将膜沿纵向延伸超过200%,同时将含水量(Z×100)%保持在10至35%的值,并将温度在 范围为(1.50 / Z + 20)℃至75℃。然后将膜预热,同时保持其含水量至少为7%,然后在45°至110°的温度下横向拉伸超过200% 然后将膜在110℃至210℃的温度下热处理,同时允许膜在横向方向收缩小于15%。 最后,将膜在张力下冷却至室温。