GB787245A - Method for the production of a coated glass fibre sheet - Google Patents

Abstract

787,245. Coated glass fibre sheets. SCHULLER, W. Nov. 20, 1953 [April 18, 1953], No. 32325/53. Drawings to Specification. Class 140. A coated glass fibre sheet is made by applying to a glass fibre web or mat two or more times in succession a plastic material so as to coat or impregnate the web or mat, heat-treating the material on the web or mat after each application, and then coating the glass fibre mat with bitumen, tar, pitch, or a composition containing one or more of these materials. The plastic material may be applied by immersing a glass fibre web in a bath containing the plastic material in a low concentration, e.g. 2 per cent and 3 per cent for the first and second applications. In one form, the second treatment is effected by spraying. A finely divided filler may be added in any treatment after the first with plastic material. The mixture of plastic material and filler may be in the form of a dough-like paste which may be applied by scrapers or doctor blades. The plastic material may be ethyl, benzyl, vinyl or acetyl cellulose, carboxylated methyl or ethyl cellulose, a cellulose ether-ester, polyvinyl chloride or acetate, polymethyl methacrylate, natural or synthetic rubber, phenol-, urea- or melamine-aldehyde resin. Where thermosetting resins are used they are preferably not hardened to the final infusible state. The filler, which may be organic or inorganic, may comprise quartz sand, powdered limestone, brick clay, kaolin or dried silicic acid. The heat treatment may be effected in chambers supplied with heated gas.