| 摘要 |
PROBLEM TO BE SOLVED: To provide a packaging material having excellent heat resistance and dead fold characteristics, and nondirectional easy tearing characteristics, which does not have bad effects on the environment. SOLUTION: The packaging material is composed by laminating at least a polystyrene biaxially oriented multi-layer film and a heat-sealing base. The polystyrene biaxially oriented multi-layer film is multi-layer film comprises A layer/B layer/A layer sequentially laminated, wherein the A layer is composed of a syndiotactic styrene polymer having a weight-average modular weight(Mw) of 150,000-300,000, or a polymer composition containing the polymer thereof, and the B layer is composed of an atactic styrene polymer having an Mw of 220,000 or greater, or a polymer composition containing the polymer thereof. An Mw ratio (SPSMw/GPPSMw) of the Mw (SPSMw) of the syndiotactic styrene polymer and the Mw (GPPSMw) of the atactic styrene polymer is 0.3-0.9. A packaged body is packaged by the packaging material.
|
