| 摘要 |
PROBLEM TO BE SOLVED: To efficiently and continuously manufacture a self-supporting bag body having a flat bottom part. SOLUTION: A bottom surface film insertion process wherein a bottom surface film 3 is inserted along a line, which continuously supplies a pair of opposed flat films 2a and 2b, in a twofold state to be fused to the flat films 2a and 2b and the bottom surface film is cut so that the length of the bottom surface film is matched with the width of the flat films, a bottom surface film folding process for folding both ends in the width direction of the bottom surface film 3 to the rear side in the advance direction of the flat films 2a, 2b, a process for inserting side surface films 4a and 4b in the gap between the bottom surface film 3 and the flat films 2a and 2b along both sides of the flat films 2a and 2b to weld them to the sides of the flat films 2a and 2b, a process for welding the rear edge part of the bottom surface film 3, which is folded to the rear side in the advance direction of the flat films 2a and 2b, to the side surface films 4a and 4b, a process for cutting off the flat films and the side surface films are successively provided to continuously manufacture the self-supporting bag body having the flat bottom part. |
