| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing, with high productivity, a rectangular-bottomed bag belonging to a field of a cushioning envelope made of a material comprising a plastic cellular sheet lined on craft paper with the minimum heat-sealed portion of the cellular sheet and little weakness in strength. SOLUTION: The manufacturing method includes steps of: (A) preparing a material (1) comprising the plastic cellular sheet (6) stuck to a rectangular piece of craft paper (5) with one of rims (51) left and applying an adhesive (52) to the rim, (B) rolling the material (1) with the plastic cellular sheet (6) inside and forming into a cylinder (2) by the adhesive (52) on the rim, (C) press- working on the cylinder (2) thereby providing a rule (7) for forming a base of the rectangular-bottomed bag, (D) gusset-folding both sides of the cylinder to provide a bag material (3) with gussets (8), and (E) heat-sealing (9) and cutting the base to complete the rectangular-bottomed bag (4). |
