| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat shrinkable film and a heat shrinkable multi-layer film which have excellent shrinking performance, spontaneous shrinking resistance and also have excellent mechanical packing properties. SOLUTION: (a) A block copolymer formed of vinyl aromatic hydrocarbon and the conjugated diene in which the mass ratio of the vinyl aromatic hydrocarbon and the conjugated diene is 50/50 to 90/10, and the block ratio of the vinyl aromatic hydrocarbon is 85% or less, and (b) as required, a composition with a specified vinyl aromatic hydrocarbon polymer is drawn by a drawing temperature at Tg+5 deg.C to Tg+20 deg.C to the glass transfer temperature (Tg) of the block copolymer composition, making the drawing extent in the vertical direction 200% or more to produce a heat shrinkable film and a heat shrinkable multi-layer film which have excellent heat shrinking properties and spontaneous shrinking resistance properties as well as excellent mechanical packing properties. |
