| 摘要 |
Sack is made of thermoplastic synthetic film. The bottom has a cross bottom fold, whose lateral edge flaps are considerably narrower than half the bottom width. The rectangular bottom opening formed by the edges of the lateral flaps of the corner flaps is enclosed by a bottom unit formed from one or more sheets of synthetic film. The latter's inside edge lies on its side falps and corner folds. It is connected with them by longitudinal and transverse seams all round and has a non-weldable layer at its surface facing the inside of the sack. Specifically, equipment for producing the sacks is described. |
