| 摘要 |
769,375. Glass fibres. THOMPSON FIBER GLASS CO.. H. I. May 2, 1955 [Aug. 2, 1954], No. 12647/55. Class 56 . Glass fibres are. leached, to form silica fibres, by a continuously flowing aqueous acid solution .,which - passes through the mass of fibres, the temperature of the acid entering the mass being, because of the exothermic reaction, lower than the temperature of the acid leaving the mass, the latter temperature being maintained below the boiling point of the solution. The fibres, either loose or in wads or batt form, but preferably not resin bonded, and of ¥ to 1 inch in length, are placed in the tank 1, preferably in a porous bag, e.g. of a cloth known by the Registered Trade Mark " Dynel." The sides of the bag may be secured to the top of the tank. The fibres are first wetted by water supplied to the nozzle 3 by a pump 19, the wetting causing the fibres to slump with consequential reduction of the interstitial spaces between them. The fibres may now be compressed and other bags containing fibres put into the tank and similarly treated. The water is now drained from the tank and acid is supplied by the pump 6 to the nozzle 3, a further slumping of the fibres occurring in the initial stages of the leaching. The acid solution is returned by a pump 10 to a tank 4 from which the pump 6 takes its suction. The solution is heated by steam jets 25. Specifications 636,893 and 732,733 are referred to. |
