Patent GB-935955-A (GB)
IPC: C23F11/173
Abstract: A metal surface, e.g. Fe, Al, Zn, Mg, Cu, Ni, Cr and alloys thereof, e.g. steel brass, Al-Mg, and Al-Mg-Si alloys, is treated, e.g. by spraying, immersing, brushing or by wiping with a rag, with a solution containing polyvinyl phosphonic acid, a copolymer of vinyl phosphonic acid or a copolymer of an acid derivative of vinyl phosphonic acid which contains, per monomer unit, only one free hydroxyl group at the phosphorus atom, e.g. an ester (monoethyl, ethyl and octyl) of vinyl phosphonic acid, or a mixture of two or more of such compounds and then dried, e.g. at 80 DEG -200 DEG C. Suitable copolymerizable components are organic compounds with one or more olefinic bonds and having a substantially polar character, e.g. acrylic and methacrylic acids and the esters (ethyl), amides and nitriles thereof, vinyl esters such as vinyl acetate and propionate, maleic anhydride and crotonic acid.  As solvents, water, aliphatic alcohols containing 1 to 4 carbon atoms per molecule (ethanol, n- and isopropanol and isobutanol) mixtures thereof, and organic solvents, e.g. benzene and acetone with a solution promoter, e.g. alcohol and water, may be used.  A wetting agent may be added.  Lacquers or varnishes, e.g. alkyd resins, may be applied to the treated metal surface.  In the examples steel plates for motor car bodies are degreased, pickled, rinsed with cold water, treated with coating composition and dried.  An alkyd resin varnish is then applied in two stages (primer and enamel) and baked.  Comparisons are made with plates which had been treated with zinc phosphatizing solution and phosphoric acid inhibited with diethyl thiourea. ALSO: A coating composition for treating metal surfaces (see Group III) comprises a solution containing polyvinylphonic acid, a copolymer of vinyl phosphonic acid or a copolymer of an acid derivative of vinyl phosphonic acid which contains, per monomer unit, only one free hydroxyl group at the phosphorus atom, or a mixture of two or more such compounds.  As solvents, water aliphatic alcohols containing 1 to 4 carbon atoms per molecule, mixtures thereof, and organic solvents, e.g. benzene and acetone, with a solution promoter, e.g. alcohol and water, may be used. Suitable copolymerizable components are organic compounds with one or more olefinic bonds, e.g. acrylic acid, methacrylic acid, and the esters, amides and nitriles thereof, vinyl esters, e.g. acetate and propionate, maleic anhydride and crotonic acid.  A wetting agent may be incorporated.  In the examples the compounds mentioned are polyvinyl phonic acid and copolymers of vinyl phosphonic acid, vinyl phosphonic acid monoethyl ester, vinyl phosphonic acid ethyl and octyl esters, acrylic acid, methacrylic acid, acrylic acid ethyl ester, vinyl acetate, and acrylonitrile. Solvents specified are water, water/isopropanol, water/ethanol, water/isobutanol, water/propano,  isopropanol, and water/acetone/isopropanol. ALSO: A metal surface, e.g. Fe, Al, Zn, Mg, Cu, Ni, Cr and alloys thereof, e.g. steel brass, Al-Mg, and Al-Mg-Si alloys, is treated, e.g. by spraying, immersing, brushing or by wiping with a rag, with a solution containing polyvinyl phosphonic acid, a copolymer of vinyl phosphonic acid or a copolymer of an acid derivative of vinyl phosphonic acid which contains, per monomer unit, only one free hydroxyl group at the phosphorus atom, e.g. an ester (monoethyl, ethyl and octyl) of vinyl phosphonic acid, or a mixture of two or more of such compounds and then dried, e.g. at 80-200 DEG  C. Suitable copolymerizable components are organic compounds with one or more olefinic bonds and having a substantially polar character, e.g. acrylic and methacrylic acids and the esters (ethyl), amides and nitriles thereof, vinyl esters such as vinyl acetate and propionate, maleic anhydride and crotonic acid.  As solvents, water, aliphatic alcohols containing 1 to 4 carbon atoms per molecule (ethanol, n-and iso-propanol and isobutanol), mixtures thereof, and organic solvents, e.g. benzene and acetone with a solution promoter, e.g. alcohol and water, may be used.  A wetting agent may be added.  Lacquers or varnishes, e.g. alkyd resins, may be applied to the treated metal surface.  In the examples, steel plates for motor car bodies are degreased, pickled, rinsed with cold water, treated with coating composition and dried.  An alkyd resin varnish is then applied in two stages (primer and enamel) and baked.  Comparisons are made with plates which had been treated with zinc phosphatizing solution and phosphoric acid inhibited with diethyl thiourea.