GB986734A - Improvements in or relating to rollers - Google Patents

Abstract

986,734. Rollers. BTR INDUSTRIES Ltd. June 6, 1962 [June 16, 1961], No. 21817/61. Heading F2U. In a roller for high temperature and pressure operations (e.g. for embossing leather cloth) comprising a non-resilient supporting core of mild steel, cast iron, brass or metal on concrete, and a cover of silicone-rubber or a blend of silicone rubber and one or more heat-resistant elastomers, e.g. "Neoprene" or "Hypalon" (Trade Mark), the cover is reinforced by an openstructure textile material close to, but not in direct contact with, the core. The core of generally cylindrical shape may have a smooth or rough outer surface. The textile material, e.g. leno or mock-leno, scrim, mull, net or cord fabric, may be pre-woven or knitted or applied in a non-structural form in the construction of the roller; alternatively the textile material may be introduced into the silicone rubber or silicone rubber/elastomer composition in long or short staple fibre form in a suitably organized pattern. The textile material may be of cotton, nylon, "Terylene" (Trade Mark), rayon, amixture of these, glass, or metal wire. The cover material may be free from the normal additional compounds or components, e.g. antistatic agents or adhesives; alternatively, if desired, reinforcing materials such as solid particles, short strands of natural or synthetic fibres or heat-resistant compounds such as inorganic fillers or epoxy resins may be included in the core material. The roller may be produced by first applying a thin layer (e.g. a coating or calendered sheet) of silicone rubber around the core which may be coated with adhesive material such as Chemlock 607, second wrapping with one or more layers of the textile material which may comprise an openweave cloth frictioned and skim-coated with silicone rubber so as to be impregnated therewith, or alternate layers of silicone-rubber sheet and cloth may be applied, and finally applying a thick coating or calendered sheet of reinforced or unreinforced silicone rubber. In a further method consisting of continuously feeding a soft grade silicone rubber composition into a nip between a rotating prepared core and an idler roll until the desired coating thickness is obtained, the cloth is introduced after the initial desired thickness has been achieved, the final coating of silicone rubber is then applied until the final thickness is obtained, and finally a tape of Terylene, nylon or cotton is then wound around and the composition is cured at a temperature of 140‹-250‹ C. for one or two hours in steam or air. A secondary heat treatment may be given.