Abstract: Provided are a treatment liquid for a black trivalent chromium conversion coating, and a trivalent chromium-containing water-soluble liquid for finishing treatment, achieving excellent corrosion resistance and scratch resistance without containing a cobalt compound, with high stability and adequate consideration for environmental issues; and a method for treating a metal substrate using the same. The treatment liquid for a black trivalent chromium conversion coating on the surface of a metal substrate contains a trivalent chromium compound, two or more organic acids or organic acid salts, or one or more organic sulfur compounds, and nitrate ions, and contains no cobalt compound.

Abstract: Provided are a treatment liquid for a trivalent chromium conversion coating, achieving excellent corrosion resistance and scratch resistance without containing a cobalt compound, with high stability and adequate consideration for environmental issues; and a method for treating a metal substrate using the same. Provided is a treatment liquid for a trivalent chromium conversion coating on the surface of a metal substrate comprising: a trivalent chromium compound; titanium lactate; one or more compounds of transition metal other than cobalt; two or more organic acids or organic acid salts, and at least one ion species selected from chloride ions, nitrate ions, and sulfate ions; but no cobalt compound.

Abstract: Provided are a treatment liquid for a trivalent chromium conversion coating, achieving excellent corrosion resistance and scratch resistance without containing a cobalt compound, with high stability and adequate consideration for environmental issues; and a method for treating a metal substrate using the same. Provided is a treatment liquid for a trivalent chromium conversion coating on the surface of a metal substrate comprising: a trivalent chromium compound; titanium lactate; one or more compounds of transition metal other than cobalt; two or more organic acids or organic acid salts, and at least one ion species selected from chloride ions, nitrate ions, and sulfate ions; but no cobalt compound.

Abstract: Provided are a treatment liquid for a black trivalent chromium conversion coating, and a trivalent chromium-containing water-soluble liquid for finishing treatment, achieving excellent corrosion resistance and scratch resistance without containing a cobalt compound, with high stability and adequate consideration for environmental issues; and a method for treating a metal substrate using the same. The treatment liquid for a black trivalent chromium conversion coating on the surface of a metal substrate contains a trivalent chromium compound, two or more organic acids or organic acid salts, or one or more organic sulfur compounds, and nitrate ions, and contains no cobalt compound.

Abstract: A galvanization system comprising an alkaline galvanization bath, a positive electrode, and a negative electrode is provided. The alkaline galvanization bath comprises galvanizing solution including about 7 to about 60 g/l of Zn, about 70 to about 200 g/l of alkali hydroxide and about 0.01 to about 5 g/l of additives. The positive electrode is insoluble in the galvanizing solution, having an opposed surface to an object which is supposed to be set in the alkaline galvanization bath and galvanized. The opposed surface of the positive electrode is formed in a rectangular pattern having a side equal to or less than 30 mm or in a circular pattern having a diameter equal to or less than 30 mm. The galvanization system can produce a galvanization membrane of excellent appearance.

Abstract: A galvanization system comprising an alkaline galvanization bath, a positive electrode, and a negative electrode is provided. The alkaline galvanization bath comprises galvanizing solution including about 7 to about 60 g/l of Zn, about 70 to about 200 g/l of alkali hydroxide and about 0.01 to about 5 g/l of additives. The positive electrode is insoluble in the galvanizing solution, having an opposed surface to an object which is supposed to be set in the alkaline galvanization bath and galvanized. The opposed surface of the positive electrode is formed in a polygonal pattern having a side equal to or less than 30 mm, which connects arbitrary two apexes of the pattern, in a polygonal pattern having a vertical line equal to or less than 30 mm, drawn between an arbitrary apex and an arbitrary side of the pattern, or in a circular pattern having a diameter equal to or less than 30 mm. The galvanization system can produce a galvanization membrane of excellent appearance.