| 摘要 |
1,204,343. Coated glass fibres. PPG INDUSTRIES Inc. 5 Oct., 1967 :[29 Dec., 1966], No. 45348/67. Heading B2E. [Also in Division D1] Glass fibres are coated and impregnated with an aqueous adhesive composition containing heat-curable resin, elastomer latex solid and volatile liquid components and passed through a dielectric heater of 5-3000 megacycles to volatilize the liquid components without substantially curing the resin to obtain a product which is sufficiently free of tack to permit processing. The tack-free elastomer coated glass fibres may be processed say, by winding, twisting, plying and weaving and combined with an elastomeric material. The term "elastomer" includes natural, or synthetic rubbers, e.g. chloroprene butadiene, isoprene polymers and copolymers thereof with acrylonitrile, styrene and isobutylene. The glass fibres may be in the form of strand, yarns, cords, fabrics, chopped fibres. In an example a rubber adhesive comprised resorcinol, formaldehyde, sodium hydroxide, butadiene-styrene-vinylpyridine terpolymer, ammonium hydroxide and water. Five strands of sized glass fibre with one-half turn per inch of twist were combined in parallel relation and passed under slight tension over rotating rollers 9 partially suspended in the adhesive 13 in Figure 1. The coated strands were passed vertically through a dielectric drying oven 17 and then upwardly through a hot gas oven 21 maintained at 300‹ to 500‹F to effect curing of the resorcinolformaldehyde resin. |
