| 摘要 |
PROBLEM TO BE SOLVED: To obtain a food packaging film suitable for heat sterilization, having specific physical properties and comprising a resin composition obtained by blending a specific ratio of thermoplastic elastomer based on a polyolefinic polymer comprising a specific block polyolefin as a main constituent. SOLUTION: This film comprises a resin composition obtained by blending 3 to 60 pts.wt. of a thermoplastic elastomer ((b) component resin) based on 100 pts.wt. of polyolefinic polymer comprising, as a main constituent, a block polyolefin resin ((a) component resin) having, as a main component, a propylene- ethylene block copolymer with a melting point of 156 to 168 deg.C, and meets with the following A to C or the like. (A) Formula I is satisfied by the ratio of an intrinsic viscosity ([η]CXS) of the xylene soluble section to an intrinsic viscosity ([η]CXIS) of the xylene insoluble section in (a) component resin at 20 deg.C, (B) formula II is satisfied by the ratio of an intrinsic viscosity ([η]F) of the film in tetralin at 135 deg.C to an intrinsic viscosity ([η]P) of (a) component resin under the same condition, and (C) formula III is satisfied by the ratio of an intrinsic viscosity ([η]F CXS) of the xylene soluble section of the film at 20 deg.C to an intrinsic viscosity ([η]CXS) of (a) component resin under the same condition. |
