GB1165222A - Process for Coating a Cellulosic Substrate with a Film-Forming Resin Composition - Google Patents

Abstract

1,165,222. Coated cellulosic substrate. WEYERHAEUSER CO. 12 Oct., 1966 [22 Oct., 1965], No. 45551/66. Heading B2K. [Also in Division C3] A cellulosic substrate e.g. lumber wood, plywood, hardboard or phenolic impregnated kraft paper overlaid plywood, is coated with a thermoplastic-thermosetting resin composition, without blistering of the coating or degradation of the substrate, by applying thereto e.g. by roll, spray, brush or curtain coater, a film of the resin composition in a liquid vehicle, impinging a hot gaseous medium against the surface of the film at a velocity sufficient to remove forcibly the liquid vehicle vapour layer in contact with the film surface and to remove the liquid vehicle substantially completely from the film, and heating the dried film to a temperature sufficient to cure the film without substantial heating of the substrate. The gaseous medium may have a velocity of from 300 to 3000 feet per minute and a a temperature up to 280‹F. The dried film may be heated e.g. under infra-red heat, to a temperature of up to 350‹F to cure the film. A primer e.g. of short or medium oil alkyd, vinyl alkyd, vinyl acrylic, urethane, thermo, plastic acrylic latex or an acrylic latex having from 20 to 80 parts to 50 to 50 parts ratio of a thermoset acrylic to thermoplastic acrylic vehicle, may be applied e.g. by rolls, spray, .brush or curtain coater, to the substrate prior to application of the thermoplastic-thermosetting resin composition. The resin composition may comprise 20 to 50 parts by weight of a thermosetting acrylic resin and 80 to 50 parts by weight of a thermoplastic acrylic resin; or 20 to 50 parts by weight of a thermosetting polyvinyl acetate resin and 80 to 50 parts by weight of a thermoplastic polyvinyl acetate resin.