| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem of a conventional filter bag wherein the filter bag is not sufficiently swollen (the efficiency in extracting tea-leaf extract is not good) because the tea-leaves inside the filter bag is pressed with front and rear filter materials in such a way as to block an opening of a filter bag body with folded-back folds after the tea-leaves are stored inside the filter bag body. <P>SOLUTION: A water-insoluble and water-permeable sheet 1 is double-folded to form side faces 2 and 3 of the bag body. The upper part of one side face 2 is folded back outward to form an outer fold part 4 and the upper part of the other side face 3 is folded back inward to form an inner fold part 5. The bottom of the bag body is tucked into the bag opening 9 side to form at least one tucked-in part 7, and the side face 2 of the bag body is tucked into the bottom of the bag body to form at least one tucked-in part 8. Both end edges of the side faces 2 and 3 are fused together with the outer fold part 4, the inner fold part 5 and the tucked-in parts 7 and 8. <P>COPYRIGHT: (C)2009,JPO&INPIT |
