Abstract: An electrical steel sheet is provided with an insulating coating which has inorganic with some organic materials, the insulating coating including inorganic components and an organic resin, the insulating coating contains, as the inorganic components, a Zr compound, a B compound, and a Si compound, specifically, when expressed as percentages in the dry coating, 20% to 70% by mass of the Zr compound (in terms of ZrO2), 0.1% to 5% by mass of the B compound (in terms of B2O3), and 10% to 50% by mass of the Si compound (in terms of SiO2), and the balance containing the organic resin.

Abstract: A method for making a phosphate-treated galvanized steel sheet, including forming a phosphate film on the surface of a galvanized layer of a galvanized steel sheet using a phosphate treatment solution containing Zn2+ and Mg2+ so as to satisfy 2.0<Zn2+?5.0 g/L, 2.0?Mg2+?5.0 g/L, and 0.4?Mg2+/Zn2+?2.5, and satisfying 0.020?free acidity/total acidity<0.10. The method allows for the quick formation of a uniform phosphate film, whereby a phosphate-treated galvanized steel sheet having excellent corrosion resistance and blackening resistance is obtained.

Abstract: A black-coated steel sheet exhibits good bendability and a good appearance after press working is provided. Zinc based plating layers, a chromium-free chemical conversion coating disposed on the zinc based plating layer, and a colored single organic coating which is disposed on the chemical conversion coating and which contains a polyester resin having a hydroxyl value of 10 KOHmg/g or more, an imino-containing melamine resin, and 5 to 15 percent by mass of carbon black are included, wherein the glass transition temperature (Tg) of the organic coating is 40° C. or higher, the film thickness is 10 ?m or less, and the hardness is 200 N/mm2 or more.

Abstract: A coated steel sheet includes a steel sheet, a galvanized layer disposed on both sides of the steel sheet, a chromium-free chemical conversion film disposed on the galvanized layers, an undercoat containing a color pigment disposed on one of the chemical conversion films, and an organic resin topcoat containing a brightening agent disposed on the undercoat, and the total thickness of the undercoat and the topcoat is 10 ?m or less. The coated steel sheet is suitable for a television cover that has high brightness and a high capability of hiding the color and flaws of a substrate.

Abstract: A method for making a phosphate-treated galvanized steel sheet, including forming a phosphate film on the surface of a galvanized layer of a galvanized steel sheet using a phosphate treatment solution containing Zn2+ and Mg2+ so as to satisfy 2.0<Zn2+?5.0 g/L, 2.0?Mg2+?5.0 g/L, and 0.4?Mg2+/Zn2+?2.5, and satisfying 0.020?free acidity/total acidity<0.10. The making method allows the quick formation of a uniform phosphate film, whereby a phosphate-treated galvanized steel sheet having excellent corrosion resistance and blackening resistance is obtained.

Abstract: Disclosed is a phosphated galvanized steel sheet comprising a steel sheet, a zinc-plating layer of ? single phase which is formed on at least one side of the steel sheet and contains Ni in an amount of not less than 10 ppm by mass and not more than the solubility limit thereof, and a phosphate layer which is formed on the zinc-plating layer and contains Mg in an amount of not less than 0.1 % by mass and less than 2.0 % by mass. Although this steel sheet is not subjected to sealing, it has corrosion resistance equivalent to or higher than those of conventional steel sheets which have been subjected to sealing, while having excellent blackening resistance.

Abstract: A coated steel sheet that has excellent bending workability, press formability, film adhesiveness after processing, solvent resistance, chemical resistance, stain resistance, weather resistance, electrical conductivity, and corrosion resistance, good surface appearance, and sufficient film hardness is provided. The coated steel sheet is produced by successively forming a galvanized layer and a chemical conversion coating free from chromium on both faces of a steel sheet, and forming a monolayer film on the chemical conversion coating at one face of the steel sheet. The monolayer film contains a polyester resin cured with a cross-linker and resin particles. The resin particles have an average particle size in the range of 3 to 40 ?m, a glass transition temperature in the range of 70° C. to 200° C., and hardness higher than that of the polyester resin.

Abstract: The phosphate-treated zinc-coated steel sheet has: a steel sheet; a zinc-coating layer of a single ?-phase containing Ni in a range from 10 ppm by mass to solid solution limit, being formed on at least one side of the steel sheet; and a phosphate-treated layer containing Mg in a range from not less than 0.1% by mass to less than 2.0% by mass, being formed on the zinc-coating layer. The steel sheet without treated by sealing has corrosion resistance equivalent to or higher than that of conventional products treated by sealing, and also has excellent blackening resistance.

Abstract: A black colored steel sheet comprises a Zn—Ni-plated steel sheet having a blackening-treated layer and a coating film on the surface of the Zn—Ni-plated steel sheet. The blackening-treated layer has a thickness of 0.01 to 1.0 ?m. The Zn—Ni-plated steel sheet having a blackening-treated layer has an arithmetical mean roughness Ra of 0.7 to 2.0 ?m and the number of peaks per inch (PPI) of at least 180.

Abstract: A black colored steel sheet has a Zn—Ni plating steel sheet which is processed by blackening treatment and a coating film formed on a surface of the Zn—Ni plating steel sheet by applying a paint composition which contains (a) metal ions, (b) a water soluble organic resin, (c) a water dispersible organic resin, (d) a glycoluril resin, and (e) an acid.

Abstract: A black galvanized steel sheet including a composite coating layer formed on a surface of a blackened galvanized steel sheet by applying a treatment solution containing a phosphate ion, a vanadate ion, a metal ion, an ?,?-unsaturated carboxylic acid and a glycoluril resin; and an organic resin layer formed on the composite coating layer, is provided. The black galvanized steel sheet is excellent in heat absorption and heat dissipation, electrical conductance, and corrosion resistance in a worked portion. Furthermore, the black galvanized steel sheet does not include hexavalent chromium.

Abstract: A black galvanized steel sheet including a composite coating layer formed on a surface of a blackened galvanized steel sheet by applying a treatment solution containing a phosphate ion, a vanadate ion, a metal ion, an ?,?-unsaturated carboxylic acid and a glycoluril resin; and an organic resin layer formed on the composite coating layer, is provided. The black galvanized steel sheet is excellent in heat absorption and heat dissipation, electrical conductance, and corrosion resistance in a worked portion. Furthermore, the black galvanized steel sheet does not include hexavalent chromium.

Abstract: In the present application, a steel sheet having surface-treated zinc-based plating is provided which comprises a zinc-based plating layer, a chromium-free conductive intermediate layer and an organic resin layer, all of the layers being superimposed one on another in the order mentioned. Even though it is of a so-called chromium-free surface-treated steel sheet, the steel sheet is more conductive and more highly resistant to corrosion than conventional chromium-free steel sheets, the likelihood of water pollution is reduced, and the steel sheet can be used in various applications as a replacement for conventional chromate-treated steel sheets.

Abstract: A composition for metal surface treatment which comprises an aluminum ion, a magnesium ion, a manganese ion, a water-soluble organic resin, an acid and water; and a surface treated metal material which has been treated with the composition. The resultant surface treated metal material is free from the danger of water contamination owing to chromium, since the composition is free of chromium, and also is excellent in both electrical conductivity and corrosion resistance. Accordingly, the metal material can be used in a wide variety of applications in place of a conventional chromate-treated steel sheet and the like.