| 摘要 |
1,041,202. Plastics valve bags. UNION CARBIDE CORPORATION. May 22, 1963 [May 28, 1962], No. 20317/63. Heading B8K. [Also in Division B5] A single- or multi-ply thermoplastics valve bag 10 (Fig. 1) has side and end bottom flaps 20, 22 and 24, 24<SP>1</SP> respectively defined by diagonal slits 28 terminating at their ends in slits 26, 31 parallel to the edge 16 of the bag blank, which flaps when folded inwardly and heat sealed together (see Division B5), form the bag bottom closure (Fig. 12, not shown). The side and end top flaps 64, 66 and 71, 72 respectively are formed by diagonal slits 62 terminating in slits 63, 65 and slits 60 parallel to the edge of the bag blank. When the end top flaps are folded inwardly, a valve sheet is heat sealed to the flap 71, and when the side flaps are folded inwardly a plate is placed between the flap 71 and the side flaps during heat sealing of the side flaps thus to form the valve of t e upper closure (Fig. 23, not shown). |
