| 摘要 |
PROBLEM TO BE SOLVED: To provide a polyester film wherein the edge scraps can be effectively reclaimed, the amount of scraps which are disposed of can be markedly reduced, and the state of existence of microcells is excellent. SOLUTION: The production process consists of preparing a film obtained by stretching a sheet prepared by coextruding a polyester A as a core and a polyester B as each end in at least the transverse direction and cutting off the ends derived from polyester B from the film. The following relationships I to III should be simultaneously satisfied: formula I: 5<=An(wt.%)<=45, formula II: 0<=Bn(wt.%)<=10, and formula III: An(wt.%)>Bn(wt.%)+5 (wherein An is the content of an incompatible thermoplastic resin in the polyester A, and Bn is the content of an incompatible thermoplastic resin in the polyester B). |
