| 摘要 |
<p>[PROBLEMS] To provide a polyester film which is excellent in heat resistance, chemical resistance, insulating characteristics, dimensional stability at elevated temperatures, and is suitable for use in a variety of fields of application such as those needing a boiling or retort treatment which requires satisfactory levels in toughness, the resistance to pin-holing, the resistance to flexing, the resistance to the breakage of a bag by dropping, impact resistance and the like, those practicing thermal molding or vacuum molding, those of bags for packaging foods containing water or drugs. [MEANS FOR SOLVING PROBLEMS] A polyester film, characterized in that it exhibits an initial modulus of elasticity at least in one direction of 2.5 to 10 GPa, an impact strength of 40 to 10000J/mm, a thermal shrinkage at 150°C at least in one direction of -0.5 to 6 %, a haze of 0.001 to 7 %, and an absolute value of the difference between the thermal shrinkage percentages in the longitudinal direction and in the transverse direction of 1.1 % or less.</p> |
