| 摘要 |
1311749 Laminating; seaming non-metallic sheet material DYNAMIT NOBEL AG 8 June 1970 [6 June 1969] 27703/70 Headings B5K and B5N A method of joining a plastic material foam 3, e.g. of polyvinyl chloride to a material 2 which is pervious to the plastics material foam when the latter is in a plastic state comprises subjecting the foam to high frequency radiation, e.g. from electrode 5 to cause it to flow in a plastic state first through the pervious material and then between projections and/or into recesses of an insulating substrate 1 adjacent to the pervious material, cooling the foam in a plastic state to mechanically join the foam to the pervious material and thereafter removing the substrate. The pervious material may be a twist, net or nettle fabric or a perforated film. The insulating substrate may be a laminate of phenolic resin impregnated paper, a siliconized glass fabric, a rubberized fabric, a rubber film, a glass fabric impregnated or coated with polytetrafluoroethylene, a polyterephthalate ester, a cellulose acetate, oil or varnish impregnated linen, a silicone film, a polyethylene or polypropylene film, oil or pergamyn impregnated paper, an epoxide resin, glass, asbestos or mica. In the embodiment shown in Fig. 1, a covering layer 4, e.g. of fabric, leather, a leather-like plastics material or a film is united with the the foam in the vicinity of the electrode 5. |
