Abstract: The present invention provides a steel sheet material used for a positive electrode can and a positive electrode can for an alkaline manganese battery capable of improving the battery characteristics for an alkaline manganese battery, characterized in that the plated steel sheet for a positive electrode can for an alkaline manganese battery has Ni-based diffusion plating layer having on the top layer many small pinholes of diameter not greater than 1 ?m, i.e. submicron pinholes, formed on the surface of the steel sheet to be used as an internal surface of the can. Said submicron pinholes preferably have, as observed by SEM, diameter in the range of 0.1˜1 ?m and are present at density not less than 30 pcs/(10 ?m×10 ?m). The surface of the steel sheet to be used as an external surface of the can preferably has a Fe—Ni diffusion plating layer and a Ni plating layer that has been softened by recrystallization.

Abstract: The present invention is intended to provide an inorganic-organic composite-treated zinc-plated steel sheet whose treated coatings do not contain any hazardous chromate and which is excellent in corrosion resistance after alkaline degreasing and coating adhesion. An inorganic-organic composite-treated zinc-plated steel sheet which has a zinc phosphate coating, in a coating weight of 0.3 to 5 g/m2, on the zinc-plated steel sheet surface and, thereon, a post-treatment coating, in a coating weight of 0.01 to 1 g/m2, containing an organic resin (A), a zirconium compound (B), an inorganic corrosion inhibitor (C) and an organic corrosion inhibitor (D).

Abstract: The present invention provides an inorganic-organic composite-treated zinc-plated steel sheet whose treated coatings do not contain any chromium and which is excellent in corrosion resistance after degreasing, coating adhesion and electrodeposition coating performance. The inorganic-organic composite-treated zinc-plated steel sheet, which is obtained by forming a zinc phosphate coating, in a coating weight of 0.3 to 5 g/m2, on the zinc-plated steel sheet surface and forming thereon a post-treatment coating, in a coating weight of 0.01 to 1 g/m2, by using a post-treatment composition containing at least one compound (A) selected from the group consisting of thiocarbonyl group-containing compounds, sulfide group-containing compounds and guanidyl group-containing compounds, an organic resin (B), a crosslinking agent (C) and an inorganic corrosion inhibitor (D).

Abstract: The present invention provides a steel sheet material used for a positive electrode can and a positive electrode can for an alkaline manganese battery capable of improving the battery characteristics for an alkaline manganese battery, characterized in that the plated steel sheet for a positive electrode can for an alkaline manganese battery has Ni-based diffusion plating layer having on the top layer many small pinholes of diameter not greater than 1 &mgr;m, i.e. submicron pinholes, formed on the surface of the steel sheet to be used as an internal surface of the can. Said submicron pinholes preferably have, as observed by SEM, diameter in the range of 0.1˜1 &mgr;m and are present at density not less than 30 pcs/(10 &mgr;m×10 &mgr;m). The surface of the steel sheet to be used as an external surface of the can preferably has a Fe—Ni diffusion plating layer and a Ni plating layer that has been softened by recrystallization.

Abstract: A zinc phosphate treated galvanized steel sheet capable of securing sufficient white rust resistance and non-uniform dew condensation resistance without requiring a sealing chromate treatment has high white color and is excellent in color tone uniformity. The galvanized steel sheet has a zinc phosphate film containing at least 2% of Mg and 0.01 to 1% of at least one element selected from the group consisting of Ni, Co and Cu, and the adhesion value of the zinc phosphate film is at least 0.7 g/m2.

Abstract: The present invention provides phosphate-treated galvanized steel sheet excellent in corrosion resistance and paintability, including: a phosphate-treated galvanized steel sheet excellent in corrosion resistance and paintability, comprising a phosphate film in an amount of at least 0.5 g/m2, containing at least 2 wt. % of Mg, and at least 0.5 wt. % in total of Ni and/or Mn, with at least 4 wt. % in total of Mg and Ni and/or Mn, formed on a zinc or zinc alloy plated steel sheet; and a phosphate-treated galvanized steel sheet excellent in corrosion resistance and paintability, comprising a phosphate film in an amount of at least 0.3 g/m2, preferably at least 1 g/m2, containing at least 2 wt. % of Mg, and at least 0.5 wt. % in total of Ni and/or Mn, with at least 5 wt. % in total of Mg and Ni and/or Mn, formed on a zinc or zinc alloy plated steel sheet.

Abstract: The present invention has an object to provide a surface-treated steel sheet which has highly balanced corrosion resistance and formability, and satisfies fundamental properties required mainly for steel sheets for automobile body, and a manufacturing method thereof. The surface-treated steel sheet of the invention is excellent in corrosion resistance and formability, comprising an amorphous inorganic film containing at least 5% magnesium and having a weight within a range of from 0.1 to 2.0 g/m2, formed on the surface of a zinc or zinc alloy plated steel sheet; wherein the inorganic film is soluble in an acidic solution and hardly soluble in a neutral or alkaline solution, and a manufacturing method thereof is provided. A zinc phosphate film may be provided between the galvanized steel sheet and the amorphous inorganic film.