| abstract |
1459106 Discontinuously-bonded air-permeable laminates FRANCE BED CO Ltd 28 Nov 1974 [8 Dec 1973] 51626/74 Heading B5N A flexible air-permeable laminate comprises a non-thermofusible surface layer 3 compression bonded at spaced locations to a thermofusible layer 2, such that at each location the layer 3 is impregnated, so as to be air-permeable, (i) with fused material from layer 2 and (ii) with further thermofusible material applied from the exterior, the materials (i) and (ii) being bonded together. The layers 2, 3 may be woven or non-woven fabric, or foam; layer 2 may include nylon, acrylic, polyester or polypropylene fibres, possibly blended with natural fibres, or polyurethane or pvc foam, and layer 3 may be of natural and/or synthetic fibre or of glass fibre. Further thermofusible and non- thermofusible layers may be present. As shown, a rayon cloth 3 and a polypropylene fibre layer 2 are bonded by ultrasonic wave heating between a vibrator 4 and an anvil 5. The material (ii) is supplied from a polypropylene sheet 9, portions being torn therefrom during the bonding operation. |