Manufacturing method of self-standing packaging bag with spout

摘要

PROBLEM TO BE SOLVED: To provide a packaging bag which has a bag bottom with planar extension for showing excellent self-supporting properties by preventing a structure in which a vertical seal provided in a bag front surface center and a bag rear surface center in a bag body part reaches the bag bottom while utilizing that the planar extension is easily formed in the bag bottom by providing a gusset in the bag body part.SOLUTION: A triangular part 19 is formed in a state to continue to a bag bottom part 14 that is spread and formed while one bag side surface lower part is overlapped with a bag front surface lower part and a bag rear surface lower part in a bag body part 2. After making the triangular part 19 into a thin plate shape by heat-sealing, the triangular part 19 is folded to the side of a bag bottom part 14 for overlapping in a state a bag bottom part forming means 24 is positioned to correspond to a boundary between the triangular part and the bag bottom part 14, and the triangular part 19 and the bag bottom part 14 are sandwiched by the bag bottom part forming means 24 and a pressure-bonding means 27 to fix by pressure-bonding.SELECTED DRAWING: Figure 1