GB826205A - - Google Patents

Abstract

826,205. Making porous sheet materials; wadding. OWENS-CORNING FIBERGLAS CORPORATON. July 8, 1957 [July 9, 1956], No. 21557/57. Classes 120(1), 120(3) and 142(4) [Also in Groups VIII and XVI] In a process for producing porous sheet material, continuous or discontinuous fibres are distributed as a layer over a foraminous surface and exposed to jets of gas having sufficient pressure to penetrate the layer to the foraminous surface to cause the fibres to interlock together. In a form, Fig. 1, in which continuous filaments are formed into mats in two stages so that a second mat is fabricated on top of the first and in which each mat is made from two strands composed of a number of filaments, glass balls pass from a hopper 10 to a furnace 12 from which they are drawn as filaments 14. After being sized at 16, e.g. with water, or an agent such as polyvinyl acetate to facilitate subsequent treatment with a reinforcing resin, the filaments are gathered into strands at 18 and are drawn through a guide 21 by rollers 22. They then impinge at considerable speed on a deflector 24 which moves in such a way as to deposit the intermixed strands 25 over the width of a foraminous conveyer 35 where the material is compacted by an adjustable belt 26 moving in the same direction as the conveyer. The mat so formed at the first stage, and the two together at the second stage, is subjected to a jet or jets of gas (e.g. air, steam, sulphur dioxide) from a blower 32, the jet(s) being fixed or oscillated across the conveyer below which is a suction box 37. Additional jets may be provided below the conveyer, and the product may be formed of more than two superposed mats. The mat may now enter a chamber 43 with a suction chamber 40 to be exposed to a fog of agents such as polyvinyl acetate or vinyl tri-ethoxy silane to facilitate subsequent wetting with polyester, after which it may be cured in an oven 46, passed to cooling rolls 52 and rolled up at 59. When discontinuous fibres are used, the filaments are broken up by a jet of gas as the material leaves the melting- furnace and are drawn down through a hood on to the foraminous conveyer by suction. Fibres of glass, rayon, alginate, superpolyamide, polyvinyl, polyvinylidene, acrylonitrile, protein or of mineral may be used. In both forms, the mat may be given a decorative pattern by providing the foraminous conveyer with depressions, bosses, apertures &c.: alternatively the pattern may be produced by subjecting the finished mat to jets of gas with or without heat while it is moving over a configurated conveyer or drum beneath or inside which there is a suction box.