| 摘要 |
PROBLEM TO BE SOLVED: To provide a self-supporting bag which is easily folded after use and is excellent in abandoning properties and recovering properties, and a method for manufacturing it. SOLUTION: A cylindrical part 4 is formed with a front face wall 1 and a back face wall facing each other, a pair of side face walls 3 and 3 arranged between these front face wall 1 and back face wall and two-folded inward. A bottom face wall 7 is welded on at least one end edge of the cylindrical part 4 to form the self-supporting bag 10. At positions where the side face walls 3 and the bottom face wall 7 are brought into contact with each other, either both side parts pinching a folding line 7c of the bottom face wall 7 or both side parts pinching folding lines of the side face walls are welded so as to come into contact with each other. Kinking parts 12 projecting outward of the self-supporting bag are formed to generate a stress on films on sides where the kinking parts 12 are formed, so that the self-supporting bag 10 is easily folded naturally. COPYRIGHT: (C)2005,JPO&NCIPI
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