| 摘要 |
PROBLEM TO BE SOLVED: To produce a polyolefin bag in which a part to be welded and a part not to be welded are located to overlap vertically each other in an automated production line. SOLUTION: An upper part polyolefin sheet 7 and a lower part polyolefin sheet 9 are laid to overlap each other, folded side part sheets of a pair are arranged between the sheets 7, 9, and an insulating sheet 11 of a material containing a fluorocarbon resin is inserted between the folded side part sheets. In this state, the lamination part consisting of the upper part sheet 7, the side part sheets, the insulting sheet 11, and the lower part sheet 9 is heated selectively. While the welding between the side part sheets is prevented, the upper part sheet 7 and the side part sheet are welded together, and the side part sheet and the lower part sheet 9 are welded together. |
