| 摘要 |
1,100,553. Seaming non-metallic sheet material; laminates. IMPERIAL CHEMICAL INDUSTRIES Ltd. 3 May, 1965 [29 May, 1964], No. 22308/64. Headings B5K and B5N. A process for welding together the two superimposed sheet materials 11 and 12 of a sandwich using a high-frequency press welder includes at least two consecutive welding stages, the electrode 5 used in one welding stage being maintained in contact with the sandwich to prevent relaxation of the sandwich after removal of welding pressure until a subsequent welding involving another electrode 6 has been completed. The term sandwich is defined as being two superimposed sheet materials, interposed between which is a padding material, the two sheet materials being weldable by a high-frequency welding technique. The sheet materials may be in the form of fabric, plastic coated fabric, fabric/ foam laminates, foam/plastic laminates or plastics. The padding may be of foamed rubber, felt, fibrous wadding, bonded cellulose acetate fibre or foamed plastics, e.g. polyurethanes, polyesters, polyethers or polyvinyls. |
