Patent GB-466480-A (GB)
Title: Protective coating
IPC: C09D5/10
Filed: 1935-08-29
Abstract: A method of forming, on a surface, a protective coating having many of the properties of a continuous metal surface, consists in applying a liquid coating-composition comprising a difficultly-combustible, non-inflammable flame-resistant organic compound, a solvent therefor, and finely-divided thin flaked metal particles dispersed therein in quantity sufficient to form a continuous surface coating of said particles, and then subjecting the coating to heat to form a continuous, lustrous metallic surface coating, tenaciously adherent to the object surface, without complete destruction of said compound. Specified flame-resistant organic compounds are fatty acid pitches, e.g. stearin pitch, bone-fat pitch, cotton-seed-oil pitch, cotton pitch, cotton-stearin pitch, cotton-seed-foots pitch and natural elastic bitumens, including asphaltites, gilsonite, glance pitch and grahamite.  Specified solvents are naphtha, benzol, orthodichlorbenzene, carbon tetrachloride and mixtures of these, and specified flakes metals are aluminium, copper, zinc, nickel and alloys thereof.  Inert, tack-reducing fillers, such as talc, silica and calcium carbonate, may be added.  Heat for "setting" the coating may be applied by the direct application of a flame, by heating the object in a muffle, by prior heating of the object to be coated, or in the course of use, e.g. in the case of locomotive smoke boxes and stacks, and temperatures destructive of ordinary paint films, but below the melting point of the metallic flakes, are used, e.g. 500--600 DEG  F.  During "setting," volatilizable and readily combustible constituents of the coating composition are driven off, and a difficultly-combustible, difficultly-soluble, hard, non-blistered and flexible bonding residue, tenaciously adherent to both the object surface and the metal particles, is obtained.  Metals and glass are mentioned as materials which may be coated by this method.  Specification 466,557 is referred to.  According to the Specification as open to inspection under Sect. 91, the coating-composition may be applied without subsequent "setting" by heat, but this subject-matter does not appear in the Specification as accepted.ALSO:A method of forming, on a surface, a protective coating having many of the properties of a continuous metal surface, consists in applying a liquid coating composition comprising a difficultly-combustible, non-inflammable, flame-resistant organic compound, a solvent therefor, and finely-divided thin flaked metal particles dispersed therein in quantity sufficient to form a continuous surface coating of said particles, and then subjecting the coating to heat to form a continuous, lustrous metallic surface coating, tenaciously adherent to the object surface, without complete destruction of said compound.  Specified flame-resistant organic compounds are fatty acid pitches, e.g. stearin pitch, bone-fat pitch, cotton-seed-oil pitch, cotton pitch, cotton-stearin pitch, cotton-seed-foots pitch and natural elastic bitumens, including asphaltites, gilsonite, glance pitch and grahamite.  Specified solvents are naphtha, benzol, orthodichlorbenzene, carbon tetrachloride and mixtures of these, and specified flaked metals are aluminium, copper, zinc, nickel and alloys thereof.  Inert, tack-reducing fillers, such as talc, silica and calcium carbonate, may be added.  Heat for setting the coating may be applied by the direct application of a flame, by heating the object in a muffle, by prior heating of the object to be coated, or in the course of use, e.g. in the case of locomotive smoke boxes and stacks, and temperatures destructive of ordinary paint films, but below the melting point of the metallic flakes, are used, e.g. 500-600 DEG  F. During setting, volatilizable and readily combustible constituents of the coating-composition are driven off, and a difficultly-combustible, difficultly-soluble, hard, non-blistered and flexible bonding residue, tenaciously adherent to both the object surface and the metal particles, is obtained.  Metals and glass are mentioned as materials which may be coated by this method. Specification 466,557, [Group III], is referred to.  According to the Specification as open to inspection under Sect. 91, the coating composition may be applied without subsequent "setting" by heat, but this subject-matter does not appear in the Specification as accepted.