NEEDLED FIBROUS STRUCTURE

摘要

1488649 Laminated fabrics IMPERIAL CHEMICAL INDUSTRIES Ltd 15 Oct 1974 [30 Oct 1973 4 Feb 1974] 50313/73 and 05019/74 Heading B5N [Also in Division D1] A laminate comprises a web of organic fibres needled to a mat of staple polycrystalline metal oxide fibres, the web being thinner than the mat. It may contain a plurality of preferably interleaved mats and webs with one or both surfaces comprised by a web. Needled organic fibres extend perpendicularly into the mat(s) to hold the laminate together and cohere the inorganic mat(s). The organic fibre webs weigh 0À5 to 5 oz./yd.2 and are formed of at least 2 inch long viscose rayon, nylon or polyester fibres. The metal oxide fibres are 0À5 to 5 micron diameter alumina or zirconia polycrystalline refractory fibres. Layers of less refractory vitreous glass, mineral wool or aluminosilicate (clay) fibres may also be incorporated. The assembly of webs and mats is laminated by needling from one side, or from one side and then the other, by barbed or forked needles to give a total of 60 to 260 punches/sq. inch. In Example 1 a viscose rayon web was needled to 4 air laid mats of zirconia fibres with 260 needle punchings 1 sq. inch penetrating 0À5 inch through the base of the structure to give a 0À75 inch thick 3 lb./cu. ft. blanket. In Example 6 the blanket of Example 1 was turned over, a rayon web applied, followed by a 1 inch thick alumino silicate fibre blanket and a further rayon web. The composite was given 260 needle punches/sq. inch. The product was used for lining a furnace, the layer of more refractory fibres being on the inside.