GB723427A - Improvements in or relating to coating compositions and methods of preparing the same - Google Patents

Abstract

In a coating composition containing a film-forming material and having a liquid phase consisting of one or more organic liquids, there is incorporated a silica flatting agent in an amount sufficient to reduce the gloss of films prepared from the composition, and a non-ionic surface-active agent in an amount sufficient substantially to prevent hard settling of the flatting agent, the surface-active agent being soluble in the composition in an amount of at least 0.05 per cent by weight. The film-forming material may be a synthetic resin-unsaturated fatty oil varnish, e.g. maleic, ester gum, modified phenolic or modified rosin-pentaerythritol resin with an oil such as linseed or tung oil, or a fatty acid or drying oil modified phthalic anhydrideglyceride resin, or a cellulose acetate-acetone lacquer, maleic-rosin lacquer, nitro-cellulose lacquer, polyvinyl chloride or vinyl chloridevinyl acetate copolymer lacquer, or a polymethyl methacrylate lacquer. The silica flatting agent may be a silica aerogel or a silica-organic liquid gel. The surface-active agent may be a condensation product of an alkyl, cycloalkyl, aryl or aralkyl mercaptan containing at least 6 and preferably not more than 20 carbon atoms with an alkylene oxide such as ethylene oxide, propylene oxide or butylene oxide. The mercaptan may be hexyl, octyl, dodecyl, tertiary dodecyl, octododecyl, cyclohexyl, methylcyclohexyl or benzyl mercaptan, or thiophenol or a thionaphthol. The surface-active agent may also be a condensation product of tall oil, rosin oil or rosin acids with an alkylene oxide such as ethylene oxide, propylene oxide or butylene oxide. Further, the surface-active agent may also be the condensation product of an alkylene oxide, such as ethylene oxide, with an alkyl carboxylic amide containing at least 7 and preferably 10 to 20 carbon atoms, such as octanamide, decanamide, laurylamide, hexadecanamide, stearamide, laurylamide or dodecanamide. The flatting agent may be added in amounts up to 30 per cent by weight of solids in the composition, and the non-ionic surface-active agent may be from 1 to 30 per cent by weight based on the flatting agent. Organic liquids mentioned are a naphthenic hydrocarbon solvent, mineral spirits and mixtures of butyl acetate, ethyl alcohol, butyl alcohol and toluol.ALSO:In a coating composition containing a film forming material and having a liquid phase consisting of one or more organic liquids, there is incorporated a silica flatting agent in an amount sufficient to reduce the gloss of films prepared from the composition and a non-ionic surface active agent in an amount sufficient substantially to prevent hard settling of the flatting agent, the surface active agent being soluble in the composition in amounts at least 0.05 per cent. by weight. The coating composition may be a drying oil varnish such as an unsaturated fatty oil varnish e.g. linseed and tung oil varnishes, natural resin unsaturated fatty oil varnishes e.g. rosin-linseed oil varnish, synthetic resin-unsaturated fatty oil varnishes e.g. maleic, ester gum, modified phenolic or modified rosin-pentaerythritol resin with an oil such as linseed or tung oil, and fatty acid or drying oil modified phthalic anhydride-glyceride resins. The composition may also be a cellulose acetate-acetone lacquer, maleic-rosin lacquer, nitro-cellulose lacquer, polyvinyl chloride or vinyl chloride-vinyl acetate copolymer lacquer, polymethyl methacrylate lacquer, or natural resin lacquer such as copal and shellac lacquers. The silica flatting agent may be a silica aerogel or a silica-organic liquid gel. The surface active agent may be a condensation product of an alkyl, cycloalkyl, aryl or aralkyl mercaptan containing a least 6 and preferably not more than 20 carbon atoms, with an alkylene oxide such as ethylene oxide, p propylene oxide or butylene oxide. The mercaptan may be hexyl, octyl, dodecyl, tertiary dodecyl, octododecyl, cyclohexyl, methyl cyclohexyl, thiophenol, thionaphthol, or benzyl mercaptan. The surface active agent may also be a condensation product of tall oil, rosin oil or rosin acids with alkylene oxides such as ethylene oxide, propylene oxide or butylene oxide. Further, the surface active agent may also be the condensation product of an alkylene oxide, such as ethylene oxide, with an alkyl carboxylic amide containing at least 7 and preferably 10 to 20 carbon atoms, such as octanamide, decanamide, laurylamide, hexadecanamide, stearamide, laurylamide or dodecanamide. The flatting agent may be added in amounts up to 30 per cent by weight of solids in the composition, and the non-ionic surface active agent may be from 1 to 30 per cent by weight based on the flatting agent.