| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing an inflation film which is formed from an ethylene-α-olefin copolymer and has high strength. SOLUTION: The ethylene-α-olefin copolymer contains units derived from ethylene and units derived from a 3-20Cα-olefin and has a flow activation energy of at least 50 kJ/mole. The melt flow rate (MFR) (unit: g/10 min) and melt viscosity (η) (unit: Pa sec) at 190°C and at shear rate 100 rad/sec of the copolymer meet formula (1):η<1,550×MFR<SP>-0.25</SP>-420. In the method for producing the inflation film fron the copolymer, when the diameter of the resin discharge opening of an annular die set in an inflation molding machine is Dd, the distance between the resin discharge opening of the annular die and a spot, where the diameter of bubbles extruded from the annular die is 1.2×Dd, is H, and the maximum diameter of the bubbles is Db, the diameter Dd of the annular die and the distance H meet formula (2): Dd×1.5<H<Dd×10, and the maximum diameter Db of the bubbles and the diameter Dd of the annular die meet formula (3): 2≤Db/Dd≤10. COPYRIGHT: (C)2006,JPO&NCIPI |
