| 摘要 |
PROBLEM TO BE SOLVED: To obtain excellent gas and odor shielding properties, mechanical characteristics, non-noisiness, flexibility or the like by forming a biodegradable barrier film out of a core barrier layer made of a polyvinyl alcohol, first and second outer layers, and forming the respective outer layers out of one type or a plurality of biodegradable linear ester amide copolymers. SOLUTION: A multilayer thermoplastic film formed of a core barrier layer made of a polyvinyl alcohol, first and second outer layers, with the same or different outer layers formed of one type or a plurality of biodegradable linear ester amide copolymers is formed. The copolymer for use in the barrier layer is formed of a partly hydrolyzed polyvinyl acetate, and a thickness of the barrier layer is set to 25 μm or below. The respective outer layers are preferably formed of the same material and constituted of a polymer selected from the group of an ester-amide copolymer containing a combination of a polyamide segment and a polyester segment in a block copolymer structure. |
