GB499238A - Improved method for preparing non-discolouring varnish coatings on wood - Google Patents

Abstract

Non-discolouring varnish coatings on wood are prepared by first coating the wood surface with a varnish containing, as film-former, a polyacrylic acid ester, a polyvinyl derivative, a polystyrol, or a resinous condensation product of phthalic acid and glycerine or of phthalic acid, a fatty acid and glycerine, and then applying one or more layers of an acidified phenol-formaldehyde resin varnish hardening at ordinary temperature. The priming varnish may contain fillers, e.g. kaolin, bole, asbestos meal, asbestine, glass dust, slate dust, potato flour, heavy spar, zinc white, lead white, iron oxide red and ochre, or the priming varnish coat may be covered with a pore filler containing a phenol-formaldehyde resin hardenable at ordinary temperature, before the final layers of acidified phenol-formaldehyde resin varnish are applied. According to an example, a steamed beech wood is first coated with a varnish containing the methyl or ethyl ester of polyacrylic acid, benzene, toluene, xylene ethyl acetate, butyl acetate, ethyl glycol acetate and the ethyl ester of lactic acid, and this coating is covered with a varnish consisting of an alcoholic solution of an alkali-condensed phenol-formaldehyde resin weakly acidified with hydrochloric acid, to which may be added higher-boiling alcohols and resins such as colophony or shellac. Specifications 459,312 and 497,762, [both in Group IV], are referred to.ALSO:Non-discolouring varnish coatings on wood are prepared by first coating the wood surface with a varnish containing, as film former, a polyacrylic acid ester, a polyvinyl derivative, a polystyrol, or a resinous condensation product of phthalic acid and glycerine or of phthalic acid, a fatty acid and glycerine, and then applying one or more layers of an acidified phenol-formaldehyde resin varnish, hardening at ordinary temperature. The priming varnish may contain fillers, e.g. kaolin, bole, asbestos meal, asbestine, glass dust, slate dust, potato flour, heavy spar, zinc white, lead white, iron oxide red and ochre, or the priming varnish coat may be covered with a pore filler containing a phenol-formaldehyde resin hardenable at ordinary temperature, before the final layers of acidified phenolformaldehyde resin varnish are applied. According to an example, a steamed beech wood is first coated with a varnish containing the methyl or ethyl ester of polyacrylic acid, benzene, toluene, xylene, ethyl acetate, butyl acetate, ethylglycolacetate and the ethyl ester of lactic acid, and this coating is covered with a varnish consisting of an alcoholic solution of an alkali-condensed phenol-formaldehyde resin weakly acidified with hydrochloric acid, to which may be added higher boiling alcohols and resins such as colophony or shellac. Specifications 459,312 and 497,762 are referred to.