Patent GB-970792-A (GB)
Title: Transparent latex finishes for interior wood
IPC: C09D133/08
Filed: 1962-04-03
Abstract: Coating compositions for wooden articles comprise at least one thickening compound, at least one antifoaming agent, a preservative, a coalescing aid and an aqueous film-forming latex of a copolymer composed of (a) between 70 and 40% by weight of at least one C1-C18 alkyl acrylate; (b) between 25 and 55% by weight of at least one monomer of the formula: <FORM:0970792/C3/1> wherein R is hydrogen or methyl and X is an aromatic hydrocarbon radical or an ester-forming group -COOY, in which Y is a cyclohexyl, a tert.-butyl or a tert.-amyl group when R is hydrogen, or a C1-C4 alkyl group when R is methyl; and (c) up to 5.0% by weight of at least one unsaturated carboxylic acid. The latices are commonly made mildly alkaline by the addition of ammonia, an amine or aminorganic base. Thickening agents specified are methyl cellulose, carboxymethylcellulose, sodium and ammonium polyacrylates, polyvinyl alcohol and ammonium hydroxide cut casein. Antifoaming agents specified are polypropylene glycol, sulphated saturated fats and an ester of coconut fatty acids. Preservatives specified are sodium o-phenylphenol tetrahydrate, sodium pentachlorophenate and phenylmercuric acetate. Coalescing aids specified are ethylene glycol monophenyl ether, ethylene and diethylene glycol monobutyl ethers, and diethylene glycol monoethyl and monobutyl ether acetates.  When it is desired to produce coated articles with a flat finish there is added to the composition an extender pigment, e.g. mica, barium sulphate, calcium carbonate, silica, magnesium and aluminium silicates and aluminium hydrate. The examples describe the preparation of coating compositions from neutralized latices of copolymers of: (1) ethyl and butyl acrylates, methyl methacrylate and methacrylic acid, and (2) styrene, 2-ethylhexyl acrylate and methacrylic acid.ALSO:Wooden articles are coated, e.g. by brushing, spraying or rolling, with at least one coat of a clear latex coating composition comprising at least one thickening compound, at least one antifoaming agent, a preservative compound, a coalescing aid and an aqueous film-forming latex of an acrylic interpolymer composed of (A) between 70 and 40% by weight of at least one C1-C18 alkyl acrylate, (B) between 25 and 55% by weight of at least one monomer of the formula <FORM:0970792/B1-B2/1> wherein R is hydrogen or methyl and X is an aromatic hydrocarbon radical or an ester-forming group -COOY, in which Y is a cyclohexyl, a tert.-butyl or a tert.-amyl group when R is hydrogen, and a C1-C4 alkyl group when R is methyl, and (C) up to 5% by weight of at least one unsaturated carboxylic acid.  The latices are commonly made mildly alkaline by the addition of ammonia, an amine or an inorganic base.  Thickening agents specified are methyl and carboxymethyl cellulose, sodium and ammonium polyacrylates, polyvinyl alcohol and ammonium hydroxide cut casein.  Antifoaming agents specified are polypropylene glycol, sulphated saturated fats and an ester of coconut fatty acids.  Preservatives specified are sodium o-phenylphenate and pentachlorophenate, and phenyl mercuric acetate. Coalescing aids specified are ethylene glycol monophenyl ether, ethylene and diethylene glycol monobutyl ethers, and diethylene glycol monoethyl and monobutyl ether acetates. When it is desired to produce coated articles with a flat finish there is added to the composition an extender pigment, e.g. mica, barium sulphate, calcium carbonate, silica, magnesium and aluminium silicates and aluminium hydrate.  The examples describe the application to fir plywood panels of two coats of compositions derived from neutralized latices of copolymers of: (1) ethyl and butyl acrylates, methyl methacrylate and methacrylic acid, and (2) styrene, 2-ethylhexyl acrylate and methacrylic acid.  The coating may be sanded and a second coat applied.