| 摘要 |
PROBLEM TO BE SOLVED: To provide, at high productivity and at a low cost, a self-supporting bag made of a laminated film so as to have a bottom shape in a gusset, the bag which is designed so that its mouth opens wide by simply cutting off the upper portion of the bag when the contents packaged in the bag is taken out, and that the opening is maintained even when the contents decrease, and, has an excellent opening performance. SOLUTION: The gusset part is formed in the bottom of the self-supporting bag. The gusset part is heat sealed in a boat-bottom shaped seal pattern such that the inside, or middle, of the gusset is low and both sides gradually become higher toward both sides of the bag. The heat seals becoming gradually higher toward both the sides of the bag are formed so as to become gradually higher from both the sides of the lower heat seal in the middle toward the corresponding sides of the bag beyond the upper end of the gusset part. A joint portion joining the front and back pleat-like portions is formed within the boat-bottom shaped seal pattern from both ends of the lower part of the gusset part toward its middle so that its length corresponds to at least the folding height of the gusset part. COPYRIGHT: (C)2009,JPO&INPIT
|
