| 摘要 |
PROBLEM TO BE SOLVED: To obtain a wrap film having transparency and excellent heat resistance or the like by biaxially orienting a raw film of a laminate of both surface layers of low-density polyethylene resins and an intermediate layer of a polypropylene-α-olefin copolymer resin, and forming an intermediate layer thickness to a specific ratio or less to the entirety of the specific thickness. SOLUTION: After a laminate of at least three layers formed at least of both surface layers of low-density polyethylene resins and an intermediate layer of a polypropylene-α-olefin copolymer is co-extruded, the laminate is quenced to make a raw material. The polyethylene resin for forming both the layers is not limited, a linear low-density polyethylene or the like is used. As the polypropylene-α-olefin copolymer resin of the intermediate layer, a copolymer of 2-10Cα-olefin such as ethylene, butene or the like is used. Then, this film is biaxially oriented twice to five times in lateral and longitudinal directions so that a total thickness is set to 5 to 50μm and an intermediate layer thickness ratio is set to 10 to 90% to the entirety. |
