| 摘要 |
PROBLEM TO BE SOLVED: To provide an easy manufacturing method for a polyethylene stretched sheet wherein so-called general purpose polyethylene as a material having a weight average molecular weight of 500,000 or less is super-stretch-formed 30 times or more. SOLUTION: A high density polyethylene having its weight average molecular weight of 500,000 or less, a polymerizable monomer, and a photopolymerization initiator are melted, kneaded and extruded into a sheet to be primarily stretched. After that, the sheet is irradiated with ultraviolet rays. Furthermore, the sheet is secondarily stretched to exceed the total stretching rate over 30 times. |
