Nippon Paint Compnay, Ltd.

Mazda Co., Ltd.

Yuichi Yoshida

Tamotsu Sobata

Masaaki Takimoto

Toshiaki Shimakura

Satoshi Ikeda

Shinji Nakano

Takeyasu Ito

Masayuki Kamimura

Kazuhiko Usuki

Mikio Nakatsukasa

Miyuki Shimada

Tetsuro Kishimoto

Mika Teraoka

Naoharu Miyazaki

Akio Takagi

The invention provides a rust inhibiting technology for zinc-coated and uncoated steel which insures at least the equivalent of results obtainable by the technology using a Cr-containing coating composition. This method comprises coating a zinc-coated or uncoated steel substrate with a water-based resin composition comprising a carboxylated polyolefin resin and 70-0 part by weight of solid matter of at least one member selected from the group consisting of polyurethane resin, polyester resin, acrylic resin, epoxy resin, and alkyd resin as supplemented with 0.01-0.5 part by weight of phosphate ion based on 100 parts by weight of total solid matter of said water-based resin composition and adjusted to a pH value of not less than 7, either followed by heating the coated substrate at 50.degree.-250.degree. C. to dry the coat or preceded by heating said steel substrate at 50.degree.-250.degree. C. to let the then-applied coat dry spontaneously.

Rust inhibiting coating composition for zinc, zinc alloy plated or

Disclosed is an acidic cleaning aqueous solution for aluminum and aluminum alloy and a process for cleaning the same, intended to execute acidic cleaning without using harmful fluoride and chloride ions. The oxidation-reduction potential of a cleaning bath is controlled to be at 0.5 to 0.8 V (vs. Ag-AgCl). The cleaning bath is obtained by diluting an acidic cleaning aqueous solution for aluminum and aluminum alloy to a predetermined volume. The acidic cleaning aqueous solution contains specified amounts of at least one of inorganic acids, Br.sup.- ions and oxidized metal ions, with the addition of a surfactant and oxidizing agent if necessary. It is thus possible to present a uniform etching effect irrespective of low temperature (below 60.degree. C.) without containing fluoride ions and chromic ions within the acidic cleaning aqueous solution. Br.sup.- also has an effect of inhibiting the oxidation-decomposition reaction of the surfactant arising from the oxidizing agent and oxidized metal ions, thereby obtaining a long-life acidic cleaning aqueous solution.

Acidic cleaning aqueous solution for aluminum and aluminum alloy and

The present invention relates to a phosphating method and solution for forming on a metal surface a phosphate film, which are used for elevating coating finish and rust-preventive property when a product consisting essentially of steel and/or zinc-plated steel combined with an aluminum alloy is coated with cationic electrocoating. The method and solution comprise that said metal surface is brought, to form a coating film, in contact with an aqueous phosphate solution which satisfies the following conditions with respect to the six kinds of ions contained. A total concentration of a sodium ion and a potassium ion is in a range of 2.0 to 15.0 (g/l). A total concentration of a manganese ion and a nickel ion is in a range of 1.0 to 5.0 (g/l). Concentration of a zinc ion is in a range of (1.6-0.02 T) to (2.5-0.02 T) (g/l). Concentration of a free F.sup.- ion is in a range of 8.0 T.sup.-1 to 20.0 T.sup.-1 (g/l), (here, T is temperature (.degree.C.) of a phosphating solution and in a range of 20 to 60). Contact of the metal surface with the phosphate solution is carried out with a combined process of dipping treatment subsequently followed by spraying treatment.

Method and treating solution for phosphating metal surfaces

Corrosive resistant, coated laminate consisting of metal substrate, anti-corrosive layer and paint layer, which is characterized by the fact that the anti-corrosive layer is formed by a composition containing, as essential components, at least one hexa-valent chromium containing chromium compound having a solubility of 20 to 10.sup.-5 and aqueous silica and/or aqueous resin as binder, and as optional component, a water soluble chromium compound having a solubility of more than 20, and the paint layer is free from chromium compound. The laminate is excellent, inter alia, in adhesion of coating and anti-corrosive property. The invention also provides a coated metal plate having excellent corrosion resistance and continuous spot weldability.

Metal coating pretreating agent

Corrosive resistant, coated laminate consisting of metal substrate, anti-corrosive layer and paint layer, which is characterized by the fact that the anti-corrosive layer is formed by a composition containing, as essential components, at least one hexa-valent chromium containing chromium compound having a solubility of 20 to 10.sup.-5 and aqueous silica and/or aqueous resin as binder, and as optional component, a water soluble chromium compound having a solubility of more than 20, and the paint layer is free from chromium compound. The laminate is excellent, inter alia, in adhesion of coating and anti-corrosive property. The invention also provides a coated metal plate hving excellent corrosion resistance and continuous spot weldability.

Corrosion resistant, coated metal laminate

Corrosion resistant, coated metal laminate, its preparation and coating

A primer composition for metallic material comprising (a) a urethane epoxy ester resin having primary hydroxyl groups and a number average molecular weight of 6000 to 12,000, (b) a chromate anticorrosive pigment and (c) a polyethylene wax having a density of 0.94 or more, a molecular weight of 1000 to 10,000 and an acid value of 15 or less (KOH mg/g), the pigment volume concentration being 24 to 45% of the total solids of the composition. A chemical pretreatment on various metallic materials for improvements in scratch resistance, corrosion resistance and the like can be obviated by the use of said primer composition.

Primer composition for a metallic material and a coating method using

A method for chemical treatment of the surface of an iron substrate which comprises (a) treating the surface with an aqueous solution containing phosphoric acid in a concentration of 0.5 to 80 weight/volume %, (b) subjecting the surface without water rinsing to treatment with an aqueous solution containing phosphoric acid with a substance capable of reacting with the phosphoric acid to give a water-soluble salt, which is hydrolyzed and/or reacted with the iron substrate to form a volatile base, and/or a substance capable of reacting with the phosphoric acid to give a water-soluble salt, which is hydrolyzed and/or reacted with the iron substrate to form a non-volatile base, the pH of the aqueous solution being 1 to 9, the total ion concentration being 0.2 to 8 weight/volume % and the concentration of the cation from the latter substance being not more than 0.5 weight/volume %, and (c) drying the surface without water rinsing.

Growing community of inventors

Kyoto, Japan

Yuichi Yoshida