Patent GB-916983-A (GB)
Title: Multicolor coating compositions
IPC: B05D5/06
Filed: 1959-04-17
Abstract: Surfaces of wood, steel, aluminium, plastics, concrete and glass are coated with a two-phase anhydrous coating composition made by preparing a carrier vehicle by dissolving a first film-former, readily soluble in hydrocarbon solvent, in an organic solvent comprising a major proportion by weight of hydrocarbon solvent, preparing a lacquer vehicle by dissolving a second film-former, readily soluble in oxygenated lacquer solvent selected from the group consisting of ethers, ketones, alcohols and mixtures thereof and insoluble in hydrocarbon solvent, in an organic solvent comprising a mixture of said oxygenated lacquer solvent and a proportion of hydrocarbon solvent which is insufficient to cause precipitation of the second film-former, and adding the lacquer vehicle slowly to the carrier vehicle while agitating the carrier vehicle to convert the lacquer vehicle to soft, pliable, discrete lacquer particles of irregular fibrous to flake-like contour dispersed in the carrier vehicle.  The size and shape of the lacquer particles may be controlled by variation in the speed of agitation of the carrier vehicle, the duration of agitation, the viscosity of the second film-former and the solids content of the lacquer vehicle, low viscosity in the second film-former and high solids content in the lacquer vehicle tending to produce flake-like lacquer particles and high viscosity in the second film-former and low solids content in the lacquer vehicle tending to produce fibrous lacquer particles.  At least one of the vehicles, prior to mixing, may be coloured, the colour after mixing then remaining with the film-former originally in the coloured vehicle.  Preferably, the lacquer vehicle prior to mixing is coloured and the colour after mixing is then wholly within the dispersed lacquer particles.  A plurality of portions of lacquer vehicle differently coloured may be separately added to the agitated carrier vehicle, forming a dispersion of differently coloured lacquer particles corresponding with said differently coloured portions of lacquer vehicle.  The invention thus provides an anhydrous twophase film-forming composition suitable for spraying and providing a continuous organic film with discrete particles embedded therein, the composition consisting essentially of a carrier vehicle having dispersed therein soft, pliable, discrete lacquer particles of irregular fibrous to flake-like contour, which lacquer particles may be coloured, and may be a mixture of differently coloured particles. The carrier vehicle may also be coloured.  The first filmformer, in the carrier vehicle, and the second film-former, in the lacquer particles, may each contain compatible plasticizer and modifier components.  In preferred compositions, the first film-former comprises cellulose acetate butyrate containing substantially 37% combined butyryl and 13% combined acetyl, and the second film-former comprises nitrocellulose having a nitrogen content of substantially 11,8-12,2%.  Specified carrier vehicles incorporate, with cellulose acetate butyrate, unmodified, resin-modified or castor-oil modified alkyl resin, rosin ester, ethylene glycol modified rosin ester, camphor gum, urea-formaldehyde resin, polyvinyl acetate, polydimethyl siloxane or polymethyl phenyl siloxane, methyl methacrylate monomer, dibutyl, dioctyl or dicyclohexyl phthalate, dioctyl adipate, triphenyl phosphate and acetyl triheptyl citrate, castor oil, toluol, xylol, petroleum naphtha, ethyl alcohol, isopropyl alcohol and butyl "Cellosolve" (Registered Trade Mark).  Specified lacquer vehicles incorporate, with nitrocellulose, unmodified, soya-modified or castor oil modified alkyl resin, rosin ester, methyl methacrylate monomer, dibutyl or dioctyl phthalate, polyethylene glycol, toluol, xylol, petroleum naphtha, butyl alcohol, butyl "Cellosolve", methyl ethyl ketone and methyl isobutyl ketone, isopropyl acetate and butyl acetate.  Specified pigments include titanium dioxide, carbon black, Ferrite Yellow, Molybdate Orange, and burnt umber, and bronze, copper and aluminium powders.  The coating is resistant to boiling water, salt spray, alcohol, oil, detergents and 10% by weight solutions of sulphuric acid, acetic acid, caustic soda and sodium carbonate.ALSO:Two-phase anhydrous coating compositions are made by preparing a carrier vehicle by dissolving a first film-former, readily soluble in hydrocarbon solvent, in an organic solvent comprising a major proportion by weight of hydrocarbon solvent, preparing a lacquer vehicle by dissolving a second film-former, readily soluble in oxygenated lacquer solvent selected from the group consisting of ethers, ketones, alcohols and mixtures thereof and insoluble in hydrocarbon solvent, in an organic solvent comprising a mixture of said oxygenated lacquer solvent and a proportion of hydrocarbon solvent which is insufficient to cause precipitation of the second film-former, and adding the lacquer vehicle slowly to the carrier vehicle while agitating the carrier vehicle to convert the lacquer vehicle to soft, pliable, discrete lacquer particles of irregular fibrous to flake-like contour dispersed in the carrier vehicle.  The size and shape of the lacquer particles may be controlled by variation in the speed of agitation of the carrier vehicle, the duration of agitation, the viscosity of the second film-former and the solids content of the lacquer vehicle, low viscosity in the second film-former and high solids content in the lacquer vehicle tending to produce flake-like lacquer particles and high viscosity in the second film-former and low solids content in the lacquer vehicle tending to produce fibrous lacquer particles.  At least one of the vehicles, prior to mixing, may be coloured, the colour after mixing then remaining with the film-former originally in the coloured vehicle.  Preferably, the lacquer vehicle prior to mixing is coloured and the colour after mixing is then wholly within the dispersed lacquer particles.  A plurality of portions of lacquer vehicle differently coloured may be separately added to the agitated carrier vehicle, forming a dispersion of differently coloured lacquer particles corresponding with said differently coloured portions of lacquer vehicle.  The invention thus provides an anhydrous two-phase film-forming composition suitable for spraying and providing a continuous organic film with discrete particles embedded therein, the composition consisting essentially of a carrier vehicle having dispersed therein soft, pliable, discrete lacquer particles of irregular fibrous to flake-like contour, which lacquer particles may be coloured, and may be a mixture of differently coloured particles. The carrier vehicle may also be coloured.  The first film-former, in the carrier vehicle, and the second film-former, in the lacquer particles, may each contain compatible plasticizer and modifier components.  In preferred compositions, the first film-former comprises cellulose acetate butyrate containing substantially 37% combined butyryl and 13% combined acetyl, and the second film-former comprises nitrocellulose having a nitrogen content of substantially 11,8-12,2%.  Specified carrier vehicles incorporate, with cellulose acetate butyrate, unmodified, resin-modified or castor-oil modified alkyl resin, rosin ester, ethylene glycol modified rosin ester, camphor gum, urea-formaldehyde resin, polyvinyl acetate, polydimethyl siloxane or polymethyl phenyl siloxane, methyl methacrylate monomer, dibutyl, dioctyl or dicyclohexyl phthalate, dioctyl adipate, triphenyl phosphate and acetyl triheptyl citrate, castor oil, toluol, xylol, petroleum naphtha, ethyl alcohol, isopropyl alcohol and butyl "Cellosolve" (Registered Trade Mark).  Specified lacquer vehicles incorporate, with nitrocellulose, unmodified, soya-modified or castor oil modified alkyl resin, rosin ester, methyl methacrylate monomer, dibutyl or dioctyl phthalate, polyethylene glycol, toluol, xylol, petroleum naphtha, butyl alcohol, butyl "Cellosolve", methyl ethyl ketone and methyl isobutyl ketone, isopropyl acetate and butyl acetate.  Specified pigments include titanium dioxide, carbon black, Ferrite Yellow, Molybdate Orange, and burnt umber, and bronze, copper and aluminium powders.  The coating composition may be applied to wood, steel, aluminium, fabrics, plastics, paper, concrete and glass, and is resistant to boiling water, salt spray, alcohol, oil, detergents and 10% by weight solutions of sulphuric acid, acetic acid, caustic soda and sodium carbonate.