| 摘要 |
PURPOSE:To enhance extensibility of a film, transparent and of superior moistureproofness by using polyethylene of high density with specific molecular weight distribution as a raw material. CONSTITUTION:Polyethylene to be used is of 0.935g/cm<3> or more of density, 0.5-20g/10min of melt index, 40-200 of ratio of high-load melt index/melt index and 5wt.% or less content of low molecular weight portion of 1,000 or less. As polyethylene with said physical properties is used in manufacturing method of a crosslinking oriented polyethylene film in which degree of crosslinking is lowered inwardly in the film thickness direction, the film of superior transparency and moistureproofness, can be oriented at the low temperature, and the range of optimum orientation temperature is enlarged, and also the film can be oriented easily without adhering to rolls. Also, the film is of good mold processing characteristics, and the thickness of raw fabric sheet in orientation can be controlled easily to carry out the orientation of the film at high speed. |
