| 摘要 |
PROBLEM TO BE SOLVED: To decrease fish eyes and die streaks occurring during long-time continuous film production to reduce film breaking and thereby to stably produce a high-quality film by compounding a mixture of a non-liq.-crystalline polyester and a copolyester with an acetic acid generation inhibitor. SOLUTION: This compsn. is produced by compounding 100 pts.wt. polyester comprising 99.9-60 wt.% non-liq.-crystalline polyester (A) and 0.1-40 wt.% copolyester (B) having mesogenic groups in the main chain with (C) 0.001-0.5 pts.wt. acetic acid generation inhibitor. Pref., ingredient C mainly comprises amorphous silica and has an average micropore size of 100-250Åand an average particle size of 0.05-5μm. The amt. of acetic acid generated of this polyester film is pref. 250 ppm or lower in terms of film quality. Pref., ingredient B is a copolyester comprising four kinds of structural units of formulas I, II, III, and IV (e.g., R1 is a group of formula V; and R2 is a group of formula VI). |
