GB459312A - Improvements in and relating to the covering of wood with resistant coatings - Google Patents

Abstract

Resistant coatings on wood are produced by treating wood with a solution of a phenolformaldehyde condensation product capable of hardening at low temperatures and then hardening at temperatures below 80 DEG C. and, if desired, at atmospheric temperature. Further coatings of solution of similar resins may be applied afterwards or the wood may be pretreated with pore fillers having as a basis a similar resin and containing, if desired, fillers such as kaolin, bole, asbestos meal, magnesium aluminium silicate, glass dust, slate meal, potato flour, heavy spar, zinc white, white lead, iron oxide red, or ochre (or other resins such as colophony, shellac and vinyl resins). The phenol-formaldehyde condensation product is employed as an aqueous or alcoholic solution, such alcohols as butyl and propyl alcohol being preferred. Dyestuffs may be added if desired. Other resins such as colophony, shellac and vinyl resins and other solvents such as ethylene glycol, ethylene glycol acetate, ethyl alcohol or acetone may be added to the phenol-formaldehyde solution or the hardened product may be varnished with other varnishes such as oil or cellulose - derivative products. The coated products are of use in the manufacture of furniture, radio apparatus, perambulators, benches, chair seats, table tops and wainscotting. In examples, resins prepared by condensing phenol or cresol with formaldehyde in the presence of caustic potash, caustic soda, sodium bicarbonate, dimethylamine or acids such as lactic, phthalic or phosphoric and, if desired, neutralized with acids such as hydrochloric, sulphuric, nitric, benzoic, salicylic or phthalic acids, are used in aqueous or alcoholic solution to coat wood and the coating afterwards hardened. A pore filler comprising a similar resin and a filler such as bole may be used to pretreat the wood. Specification 377,587 is referred to.