Patent GB-777584-A (GB)
Title: Improvements in or relating to metal-containing surface coatings
Inventor: HASLAM JOHN HARRIS
IPC: B05D3/10
Filed: 1954-07-23
Abstract: Solid surfaces are coated by applying thereto a layer of an hydrolysable organic alcoholate, containing 1 to 8 carbon atoms per organic radical, and derived from a Group IV (a) metal, the layer containing from 0.0003 to 0.0375 gram molecules of the alcoholate per square metre of surface, and hydrolysing the alcoholate to obtain an adherent polymeric metal oxide film. Hydrolysis may be effected by atmospheric moisture vapour, and may take place at normal or elevated temperatures.  The alcoholate may be applied as such or as a dilute solution in a volatile organic solvent by brushing, spraying, dipping, doctoring, or evaporation and condensation procedures. Alcoholates derived from monohydric alcohols and chloro-alcohols and titanium, zirconium, hafnium and thorium, and prepared by known methods, may be used.  The films of the invention may be used as primers on glass, paint, metal ceramics, polyamides, cellulosic films and other plastics, including fibres and sheets, to increase the adhesion of subsequently applied enamels, glass, paint, plastics or rubber, or as top coatings on highgloss enamels or plastics, optical lenses or other glass articles, photographic films, transparent flexible sheeting material, glass or other artificial fibres and bristles, or metal surfaces, or for bonding safety glass.  In examples: (1) a solution of tetraethyl titanate in ethanol is sprayed on a stainless steel sheet and dried in air at about 50 per cent relative humidity; (2) tetrabutyl titanate was sprayed on a sheet of "Cellophane" (Registered Trade Mark) and exposed to air at about 35 per cent relative humidity; the product could be coated with resins or other polymeric substance such as nitrocellulose to give a laminate; (3) a glass panel was coated with a solution of 2-ethyl hexyl titanate in xylene, dried in air at 25 per cent relative humidity, and then heated to 400 DEG  C.; (4) small squares of aluminium foil, having corner tabs, were dipped in a solution of tetrabutyl titanate in butanol, hung in moist air, and then baked at 200 DEG  C.; they were then interleaved with polyethylene sheets, and hot pressed to form a electrical condenser.  Further, copper wire may be coated with the film of the invention and molten polythene then applied to form an insulating coating. Laminated safety glass may be made, e.g. by coating glass plates with a dilute solution of tetrabutyl zirconate, evaporation of the solvent, and hydrolysis, the treated surfaces being placed on either side of a sheet of polybutyral resin and bonded thereto.ALSO:Glass and nylon fibres are coated by applying thereto a layer of a hydrolisable alcoholate, containing 1-8 carbon atoms per organic radical and derived from a Group IV(a) metal, and hydrolising the alcoholate to obtain an adherent metal oxide film.  Hydrolysis may be effected by atmospheric moisture vapour, and may take place at normal or elevated temperature.  The alcoholate may be applied as such or as a dilute solution in a volatile organic solvent by brushing, spraying, dipping, doctoring, or evaporation and condensation procedures. Alcoholates derived from monohydric alcohols and chloroalcohols and titanium, zirconium, hafnium and thorium may be used.ALSO:Solid surfaces are coated by applying thereto a layer of a hydrolyzable organic alcoholate, containing 1 to 8 carbon atoms per organic radical, and derived from a Group IVA metal, the layer containing from 0.0003 to 0.0375 gram molecules of the alcoholate per square metre of surface, and hydrolysing the alcoholate to obtain an adherent polymeric metal oxide film.  Hydrolysis may be effected by atmospheric moisture vapour, and may take place at normal or elevated temperatures.  The alcoholate may be applied as such or as a dilute solution in a volatile organic solvent by brushing, spraying, dipping, doctoring, or evaporation and condensation procedures. Alcoholates derived from monohydric alcohols and chloro-alcohols and titanium, zirconium, hafnium and thorium, and prepared by known methods, may be used.  The films of the invention may be used as primers on glass, paint, metal, ceramics, polyamides, cellulosic films and other plastics, including fibres and sheets, to increase the adhesion of subsequently applied enamels, glass, paint, plastics or rubber, or at top coatings on high gloss enamels or plastics, optical lenses or other glass articles, photographic films, transparent flexible sheeting material, glass or other artificial fibres and bristles, or metal surfaces, or for bonding safety glass. In examples (1) a solution of tetraethyl titanate in ethanol is sprayed on a strainless steel sheet and dried in air at about 50 per cent relative humidity; (2) tetrabutyl titanate was sprayed on a sheet of "Cellophone" (Registered Trade Mark) and exposed to air at about 35 per cent relative humidity; the product could be coated with resins or other polymeric substance such as nitrocellulose to give a laminate; (3) a glass panel was coated with a solution of 2-ethyl hexyl titanate in xylene, dried in air at 25 per cent relative humidity, and then heated to 400 DEG C.; (4) small squares of aluminium foil, having corner tabs, were dipped in a solution of tetrabutyl titanate in butanol, hung in moist air, and then baked at 200 DEG C.; they were then interleaved with polyethylene sheets, and hot pressed to form an electrical condenser.  Further, copper wire may be coated with the film of the invention and molten polythene then applied to form an insulating coating.  Laminated safety glass may be made, e.g. by coating glass plates with a dilute solution of tetrabutyl zirconate, evaporation of the solvent, and hydrolysis, the treated surfaces being placed on either side of a sheet of polybutyral resin and bonded thereto.