| 摘要 |
A method of producing a synthetic foil flat-bottom bag capable of receiving liquid, fluid or pourable material and capable of standing up-right when filled, in which a bag closed at the bottom and open at the top is spread apart at opposite sides whereby at its bottom, a bottom surface with two outwardly pointed triangular tips is formed. The two tips are compressed flat with their two-foil walls and are folded downwardly by approximately 180 DEG about a fold line laterally spaced from the bottom of the bag, while the tip ends are placed against the underside of the bottom wall. Thereafter the two tip folds are crease-welded. The thus produced bag has a supporting surface which is enlarged by the welded multi-layer folds and is stabilized, and tightly sealed by the crease welds in the area of the tip. The folding of the tip is preferably effected by means of a form plate which has two parallel form edges extending beyond the bottom surface of the bag. Upon folding and prior to crease-welding of the tips the form plate is removed. |
