GB943016A - Production of glass fibres - Google Patents

Abstract

<PICT:0943016/C1/1> The fibres are produced by flowing through orifices in a bushing molten glass produced from glass bodies coated with fluxing material in quantity sufficient to facilitate melting of the glass but insufficient to alter the composition of the glass appreciably. Suitable fluxes are boric acid, borax, sodium fluoride, sodium silico-fluoride, phenol formaldehyde condensation products and ammonium acetate. Fig. 2 shows a suitable coating apparatus. Marbles are fed from a platform 25 to a hopper 26 whence they fall through a slit into the spaces between divider bars 31 on a rotating roller 28 which drops them into the spaces between inclined pipes 32. As they roll down they are sprayed with a solution fed from a longitudinal slot in a tube 34. They then roll down a trough 49 on to a mesh conveyer belt 50 in a drying lehr 51. The coating solution is mixed in a tank 42 and fed by a pump 39 to a tank 37 which feeds the distributer pipe 34. Excess solution is caught by a tray 47 and fed back to the tank 42. When coating with boric acid the solution may contain an excess of boric acid in suspension. The preparation of a suitable phenol-formaldehyde condensation product is described.