1443754 Needled fabric laminates; use thereof for reinforcing foams and resins BAYER AG 31 Oct 1973 [31 Oct 1972] 50613/73 Heading B5N A composite structure for reinforcing foam mouldings comprises layers (a) and (b) needled together, layer (a) comprising a plurality of non- woven sublayers whose fibre diameters decrease from one to the other towards layer (b) which comprises a plurality of woven fabrics of which the one adjacent layer (a) is a fine-mesh fabric of weight 50-100 g./m.SP2/SP, of equal strength in each direction, and whose meshes are sufficiently fine to prevent the free flow of subsequentlyapplied impregnating resin. The balance of layer (b) may comprise up to 10 fabrics of weight up to 400 g./m.SP2/SP, and layer (b) may weigh 200-2500 g./m.SP2/SP. Layer (a) may comprise two or three sublayers; suitable deniers are specified. Specified materials are (a) glass and (b) glass and/or synthetics. Sublayers (a) may be needled before layer (a) is needled to layer (b). In use, the structure is vacuum-impregnated with unsaturated polyester, epoxy or polyurethane resin to embed layer (b) and form a outer gel coat, and a foamable polyurethane mixture intended to constitute part of the moulding is applied to impregnate layer (a). Two structures may be superposed for increased reinforcement. The Specification describes a known composite structure for similar purposes, which comprises a needled assembly of (i) a coarsedenier non-woven coconut, glass or synthetic fibre layer, (ii) a fine-denier non-woven acrylic, polyester or polyamide fibre layer, and (iii) one or more woven fabrics and/or mats of glass, asbestos, metallic or synthetic fibres.
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