| 摘要 |
1487744 Plastics bags UNION CARBIDE CORP 20 Sept 1974 [21 Sept 1973] 41024/74 Heading B8K A flat-flexible multi-ply plastics film article comprises two superimposed plies of flat flexible plastics film 11, 12 having opposite edges 13, 14 joined, and an openable end 16, a portion 17 of the ply 11 being distorted after forming the article to enable the plies to be readily separated to open the article. The article may be a tube or, as shown, a bag, Fig. 6, or a continuous strip of readily separable bags, Fig. 8. The distortion 17 or 42 may be present over part or all of the width of the bag near its openable end and may be produced mechanically, by irradiation, or preferably by the application of heat to heatshrinkable film material. The heat may be applied by a heated bar, torch flame, or a hot air gun directed through a template. The edges 13, 14, Fig. 6, may be joined by heat-sealing, or adhesive bonding, or may be folds of a flattened tube. The film material may be polyethylene, polypropylene, p.v.c., a polyester or polyvinylidene chloride and copolymers thereof. |
