GB464101A - Improvements in anti-corrosion coating compositions - Google Patents

Abstract

An anti-corrosion coating-composition comprises a coating agent having incorporated therewith an adsorbent substance charged with a corrosion-preventing agent or agents other than chromic acid or a chromate, and other than an agent in the gaseous or vaporous state having an alkaline or neutral reaction. Any of the usual binding agents, such as asphalts, bitumen, tar, drying oils, cellulose esters or ethers, natural or artificial resins, rubber, gelatine and casein, may be used, and suitable adsorbents are carbon, such as charcoal or coke, silica gel, silicates, precipitated and "grown" alumina, iron oxides, slags, zinc oxide, amorphous or microcrystalline sulphides such as lead sulphide or cadmium sulphide, amorphous phosphates, e.g. those of manganese and iron, litharge and red lead. Specified corrosion-preventing agents are benzylamine, methyl aniline, pyridine, ethanolamine, propylamine, ethylene diamine, piperidine, carbonic acid, hydrocyanic acid, phosphoric acid, nitric acid, sulphurous acid, hydrofluoric acid, nitrous gases, hydrogen sulphide, diethyl ether, benzene, methylene chloride, chloroform, alkyl esters such as alkyl nitrites and alkyl nitrates, fluorides, sulphides, phosphates, inorganic and organic salts of zinc, lead, mercury, silver, copper and thallium, phenols, cyanogen halide, bromoacetone, lead tetraethyl, propyl mercury, quinoline, nicotine, halogen-substituted dialkyl sulphides, and inorganic and organic derivatives of phosphorus, arsenic and antimony. More than one adsorbent substance, and more than one corrosion-preventing agent may be present, and in some cases the adsorbed substance may be fixed on the substratum by after-treatment with metal salts, so as to secure very gradual emission. Additional protective agents, dissolved or suspended in the binding substance, may be present and metallic lead, aluminium, copper, zinc and iron, lead oxide, iron oxide, copper oxide, zinc oxide, lithopone, metal sulphides, lead chromate, white lead, and chromium oxide are mentioned. Driers and thinners may be added. According to examples, anti-corrosion coating compositions contain: (1) linseed oil, artificial resin, cobalt resinate, powdered copper, turpentine oil, charcoal loaded with nitrobenzol, and red lead loaded with pyridine by treatment with an aqueous solution thereof and subsequently fixed with mercuric chloride; (2) linseed oil varnish, micaceous iron ore, manganese resinate, and active carbon loaded with hydrogen sulphide; (3) coal tar, iron powder, and a mixture of colloidal alumina and active carbon loaded with carbon dioxide, or carbon alone loaded with silicon fluoride or silicon hydride; a diluent such as petroleum or benzine may be added; (4) linseed oil varnish and active carbon loaded with phosphoric acid, with or without red iron oxide; (5) titanium oxide loaded with aqueous pyridine solution and after-treated with corrosive sublimate solution. Specifications 3356/95, [Class 98], 435,003, and 459,149, are referred to. According to the Specification as open to inspection under Sect. 91, ammonia, methylamine, hydrogen, oxygen, ozone, ethane, propane, hexane, ethylene, acetylene, and carbon monoxide may be used as adsorbed corrosion-preventing agents, and barium chromate also may be present in the coating compositions. This subject-matter does not appear in the Specification as accepted.