| 摘要 |
<p>Portable bottomed bag of such construction that has a tubular body portion (13) with single fold each side, a flat upper opening portion and a hexagonal bottom face and is capable of completely sealing the bottom of the bag. Manufactured by the following manner: the lower end of a tubular body (13) is folded at a suitable fold or reference line, the distance of which from the lower end portion is a little longer than half of the face width of the tubular body so that there may be a square portion (14) with some margins overlapped with each other by fully expanding the lower portion up and down or by fully pulling apart the respective lower end centre portions of the front and rear layers of the tubular body. The margins are then heat sealed in edge joint style to form the first heat-sealed portion (15). The upper and lower halves of the square portion are heat sealed along parallel symmetrical lines (16a, 16b) at a suitable distance from the fold over a fixed width to form a hexagonal bottom face. Those portions outside the secondly heat-sealed portions of the upper and lower halves are cut off to leave reinforcing, self-sustaining fins, or the secondly heat-sealed portions alone.</p> |
