| 摘要 |
1314964 Scoring FOSTER GRANT CO Inc 16 Feb 1971 4778/71 Heading B6J Score lines are produced in heat-destructible foamed thermoplastics mesh material by thermally destroying a portion of the thickness of the material along the required lines. The lines may be produced by bringing heated elements such as discs, wires or bars into close proximity ( but preferably not into contact) with the mesh. The plastics material may be foamed polystyrene, polyethylene or polypropylene. The mesh may be laminated to a continuous plastics film, e.g. of polyethylene. The mesh 10 may be transversely scored by a heated blade 38 on a rotatable shaft 36 and longitudinally scored by heated bars 28. |
