| 摘要 |
PURPOSE:To increase impact strength by specifying the thickness of a part in contact with a belt of seal bar insert in a heating zone to achieve sealing. CONSTITUTION:A heating zone and a cooling zone are made up of a pair of belts respectively. When a resin film 7 is sealed in the heating zone, the thick ness of a part 6 in contact with a belt 8 of seal bar insert is made 1 - 6 mm to achieve sealing. The part 6 in contact with the belt 8 of seal bar insert is made twofold or more depending on the kind of matters to be filed in a bag. Consequently, surging phenomenon, which occurs immediately after the resin film 7 has been separated from the belt of the heating zone, is avoided, so that the resin film can be sealed. As a result, sealing can be accomplished without lowering impact strength due to surging phenomenon of a sealed part. |
