| 摘要 |
PROBLEM TO BE SOLVED: To obtain a multilayered stretched polypropylene film showing an excellent balance between stiffness and heat seal strength. SOLUTION: In the multilayered stretched polypropylene film obtained by stretching a sheet made by laminating a layer containing a propylene/1-butene copolymer (B) having a melting point of≤140°C on at least one surface of the base material layer containing a propylene polymer (A) having a melting point of≥155°C, a ratio ((B)/(A)) of the thickness of the layer containing the propylene/1-butene copolymer (B) to the thickness of the base material layer containing the propylene polymer (A) is 0.025 to 0.25, and heat shrinkage in a lateral direction and/or longitudinal direction at 120°C is≤3.0%. COPYRIGHT: (C)2011,JPO&INPIT |
