| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve tackiness, microwave oven applicability, saw blade cutting by a method in which a multilayer film having a polypropylene layer of a specified melting point between polyethylene front and rear surface layers is irradiated with ionizing radiation and simultaneously drawn in the film take-up direction. SOLUTION: A film having at least one layer of polypropylene of 140 deg.C or more melting point between polyethylene front and rear surface layers is irradiated with ionizing radiation and simultaneously is drawn in the film take-up direction by using heat generated by the irradiation without being reheated. Usually, the preferable dosage of the ionizing radiation for the multilayer film is 5-30M rad and acceleration voltage is 150-200kV. It is preferable to set up the velocities of drawing so the velocity on the outlet side of an irradiation apparatus is 2-5 times that on the inlet side of the apparatus to make the draw ratio 5-10.</p> |
