Abstract: A hot-dip Zn alloy plating layer is formed on a surface of a base steel sheet by immersing the base steel sheet in a hot-dip Zn alloy plating bath containing Al and Mg. An aqueous solution containing a polyatomic ion including Si4+ and/or a polyatomic ion including Cr6+ is then contacted with a surface of the hot-dip Zn alloy plating layer. All of the aqueous solution coating the surface of the hot-dip Zn alloy plating layer is removed with a squeeze roller. The aqueous solution contains the polyatomic ion in a concentration of 0.01 g/L or more in terms of atom of Si and Cr. A surface temperature of the hot-dip Zn alloy plating layer when the aqueous solution is contacted with the surface of the hot-dip Zn alloy plating layer is 100° C. or above and equal to or less than a solidifying point of the plating layer.

Abstract: A method of producing a hot-dip Zn alloy-plated steel sheet comprising: dipping a base steel sheet in a hot-dip Zn alloy plating bath to form a hot-dip Zn alloy plating layer on a surface of the base steel sheet; and contacting an aqueous solution containing a vanadium compound with a surface of the hot-dip Zn alloy plating layer to cool the base steel sheet and the hot-dip Zn alloy plating layer having a raised temperature through formation of the hot-dip Zn alloy plating layer, and to form a composite oxide film on the surface of the hot-dip Zn alloy plating layer. A temperature of the hot-dip Zn alloy plating layer when the aqueous solution is to be contacted with the hot-dip Zn alloy plating layer is equal to or more than 100° C. and equal to or less than a solidifying point of the hot-dip Zn alloy plating layer.

Abstract: A hot-dip Zn alloy plating layer is formed on a surface of a base steel sheet by immersing the base steel sheet in a hot-dip Zn alloy plating bath containing Al and Mg. An aqueous solution containing one of or two or more of polyatomic ions selected from the group consisting of a polyatomic ion including V5+, a polyatomic ion including Si4+, and a polyatomic ion including Cr6+ is then contacted with a surface of the hot-dip Zn alloy plating layer. The aqueous solution contains the polyatomic ion in a concentration of 0.01 g/L or more in terms of one of or two or more of atoms selected from the group consisting of V, Si, and Cr.

Abstract: Provided is a method for obtaining a chemical conversion coating-treated zinc-aluminum-magnesium alloy-plated steel sheet having extremely excellent in corrosion resistance and adhesiveness to a resin coating film. The method is for treating the surface of a zinc-aluminum-magnesium alloy-plated steel sheet with a metal surface treatment agent, in which the metal surface treatment agent contains a compound (A) having a zirconyl ([Zr?O]2+) structure, a vanadium compound (B), a titanium fluorocomplex compound (C), an organic phosphorus compound (Da) containing a phosphoric acid group and/or a phosphonic acid group, an inorganic phosphorus compound (Db), a specific aqueous acrylic resin (E), and an oxazoline group-containing polymer (F) as a curing agent, each in a predetermined amount, and the pH of the metal surface treatment agent is 3 to 6.

Abstract: A method of producing a hot-dip Zn alloy-plated steel sheet includes: dipping a base steel sheet in a hot-dip Zn alloy plating bath to form a hot-dip Zn alloy plating layer on a surface of the base steel sheet; and contacting an aqueous solution containing a water-soluble corrosion inhibitor with a surface of the hot-dip Zn alloy plating layer to cool the base steel sheet and the hot-dip Zn alloy plating layer having a raised temperature through formation of the hot-dip Zn alloy plating layer. A temperature of the surface of the hot-dip Zn alloy plating layer when the aqueous solution is to be contacted with the surface of the hot-dip Zn alloy plating layer is equal to or more than 100° C. and equal to or less than a solidifying point of the plating layer. The aqueous solution containing the water-soluble corrosion inhibitor satisfies the Equation [{(Z0?Z1)/Z0}100?20].

Abstract: The present disclosure relates to a chemically treated zinc-based plated steel sheet that is superior in weather resistance, water resistance, blackening resistance and film adhesion. A chemical conversion film having a thickness 0.5-10 ?m is formed by coating and drying a chemical treatment solution on a surface of an aluminum-containing zinc-based alloy plated steel sheet. The chemical treatment solution contains a fluororesin containing 0.05-5% by weight of a hydrophilic functional group selected from the group consisting of a carboxyl group and a sulfonic acid group and 7-20% by weight of a fluorine atom, the fluororesin in which a number-average molecular weight is 1,000-2,000,000, and an oxoate, a fluoride, a hydroxide, an organic salt, a carbonate or a peroxygenated salt of a group 4A metal.

Abstract: A black-plated steel sheet has a Zn-plating layer containing molten Al and Mg, containing Al in the amount of 1.0-22.0 mass %, containing Mg in the amount of 1.3-10.0 mass %, and having a Zn black oxide distributed in a lamella pattern in the plating layer. The Zn black oxide is a Zn oxide derived from a Zn2Mg phase. The brightness of the surface of the Zn-plating layer containing the molten Al and Mg has an L* value of 60 or less.

Abstract: A method of producing a hot-dip Zn alloy-plated steel sheet includes: dipping a base steel sheet in a hot-dip Zn alloy plating bath to form a hot-dip Zn alloy plating layer on a surface of the base steel sheet; and contacting an aqueous solution containing a water-soluble corrosion inhibitor with a surface of the hot-dip Zn alloy plating layer to cool the base steel sheet and the hot-dip Zn alloy plating layer having a raised temperature through formation of the hot-dip Zn alloy plating layer. A temperature of the surface of the hot-dip Zn alloy plating layer when the aqueous solution is to be contacted with the surface of the hot-dip Zn alloy plating layer is equal to or more than 100° C. and equal to or less than a solidifying point of the plating layer. The aqueous solution containing the water-soluble corrosion inhibitor satisfies the Equation [{(Z0?Z1)/Z0}100?201.

Abstract: Provided is a method for obtaining a chemical conversion coating-treated zinc-aluminum-magnesium alloy-plated steel sheet having extremely excellent in corrosion resistance and adhesiveness to a resin coating film. The method is for treating the surface of a zinc-aluminum-magnesium alloy-plated steel sheet with a metal surface treatment agent, in which the metal surface treatment agent contains a compound (A) having a zirconyl ([Zr?O]2+) structure, a vanadium compound (B), a titanium fluorocomplex compound (C), an organic phosphorus compound (Da) containing a phosphoric acid group and/or a phosphonic acid group, an inorganic phosphorus compound (Db), a specific aqueous acrylic resin (E), and an oxazoline group-containing polymer (F) as a curing agent, each in a predetermined amount, and the pH of the metal surface treatment agent is 3 to 6.

Abstract: The present invention pertains to a method for producing a black-plated steel sheet capable of being blackened in a short amount of time, and exhibiting an excellent ability to maintain a black appearance after processing. As an original sheet, the sheet used is a Zn-plating steel sheet which contains molten Al and Mg and has a Zn-plating layer containing molten Al and Mg, containing Al in the amount of 0.1-22.0 mass %, inclusive, and containing Mg in the amount of 0.1-1.5 mass %, inclusive. The plating layer is blackened by causing the molten-plating steel sheet to contact water vapor inside a tightly sealed container. When doing so, the concentration of oxygen inside the tightly sealed container is 13% or less.

Abstract: The present invention pertains to a method for producing a black-plated steel sheet capable of being blackened in a short amount of time, and exhibiting an excellent ability to maintain a black appearance after processing. As an original sheet, the sheet used is a Zn-plating steel sheet which contains molten Al and Mg and has a Zn-plating layer containing molten Al and Mg, containing Al in the amount of 1.0-22.0 mass %, inclusive, and containing Mg in the amount of 1.5-10.0 mass %, inclusive. The plating layer is blackened by causing the molten-plating steel sheet to contact water vapor inside a tightly sealed container. When doing so, the concentration of oxygen inside the tightly sealed container is 13% or less.

Abstract: This hot-dip Zn-alloy-plated steel sheet comprises: a steel sheet; a hot-dip Zn-alloy-plated layer arranged on a surface of the steel sheet; and a complex oxide coating film arranged on a surface of the hot-dip Zn-alloy-plated layer. The complex oxide coating film includes vanadium and a constituent component of the hot-dip Zn-alloy-plated layer, and the entire surface of the coating film satisfies the following formula (1): S[Hydroxide]/(S[Hydroxide]+S[Oxide])×100?40. In formula (1): S[Oxide] is the area exhibited by a peak having a center at approximately 1022 eV ascribable to a Zn oxide in an intensity profile in XPS analysis of the surface of the complex oxide coating film; and S[Hydroxide] is the area exhibited by a peak having a center at approximately 1023 eV ascribable to a Zn hydroxide in an intensity profile in XPS analysis of the surface of the complex oxide coating film.

Abstract: This hot-dip Zn-alloy-plated steel sheet comprises: a steel sheet; and a hot-dip Zn-alloy-plated layer arranged on a surface of the steel sheet. The entire surface of the hot-dip Zn-alloy-plated layer satisfies the following formula (1): S[Zn(OH)2]/(S[Zn(OH)2]+S[Zn])×100?40. In formula (1): S[Zn] is the area exhibited by a peak having a center at approximately 1022 eV ascribable to metallic Zn in an intensity profile in XPS analysis of the surface of the hot-dip Zn-alloy-plated layer; and S[Zn(OH)2] is the area exhibited by a peak having a center at approximately 1023 eV ascribable to Zn(OH)2 in an intensity profile in XPS analysis of the surface of the hot-dip Zn-alloy-plated layer.

Abstract: The present disclosure relates to a chemically treated zinc-based plated steel sheet that is superior in weather resistance, water resistance, blackening resistance and film adhesion. A chemical conversion film having a thickness 0.5-10 ?m is formed by coating and drying a chemical treatment solution on a surface of an aluminum-containing zinc-based alloy plated steel sheet. The chemical treatment solution contains a fluororesin containing 0.05-5% by weight of a hydrophilic functional group selected from the group consisting of a carboxyl group and a sulfonic acid group and 7-20% by weight of a fluorine atom, the fluororesin in which a number-average molecular weight is 1,000-2,000,000, and an oxoate, a fluoride, a hydroxide, an organic salt, a carbonate or a peroxygenated salt of a group 4A metal.

Abstract: The present disclosure relates to a chemically treated zinc-based plated steel sheet that is superior in weather resistance, water resistance, blackening resistance and film adhesion. A chemical conversion film having a thickness 0.5-10 ?m is formed by coating and drying a chemical treatment solution on a surface of an aluminum-containing zinc-based alloy plated steel sheet. The chemical treatment solution contains a fluororesin containing 0.05-5% by weight of a hydrophilic functional group selected from the group consisting of a carboxyl group and a sulfonic acid group and 7-20% by weight of a fluorine atom, the fluororesin in which a number-average molecular weight is 1,000-2,000,000, and an oxoate, a fluoride, a hydroxide, an organic salt, a carbonate or a peroxygenated salt of a group 4A metal.

Abstract: A hot-dip Zn alloy plating layer is formed on a surface of a base steel sheet by immersing the base steel sheet in a hot-dip Zn alloy plating bath containing Al and Mg. An aqueous solution containing a polyatomic ion including Si4+ and/or a polyatomic ion including Cr6+ is then contacted with a surface of the hot-dip Zn alloy plating layer. All of the aqueous solution coating the surface of the hot-dip Zn alloy plating layer is removed with a squeeze roller. The aqueous solution contains the polyatomic ion in a concentration of 0.01 g/L or more in terms of atom of Si and Cr. A surface temperature of the hot-dip Zn alloy plating layer when the aqueous solution is contacted with the surface of the hot-dip Zn alloy plating layer is 100° C. or above and equal to or less than a solidifying point of the plating layer.

Abstract: A hot-dip Zn alloy plating layer is formed on a surface of a base steel sheet by immersing the base steel sheet in a hot-dip Zn alloy plating bath containing Al and Mg. An aqueous solution containing one of or two or more of polyatomic ions selected from the group consisting of a polyatomic ion including V5+, a polyatomic ion including Si4+, and a polyatomic ion including Cr6+ is then contacted with a surface of the hot-dip Zn alloy plating layer. The aqueous solution contains the polyatomic ion in a concentration of 0.01 g/L or more in terms of one of or two or more of atoms selected from the group consisting of V, Si, and Cr.

Abstract: The present invention pertains to a method for producing a black-plated steel sheet capable of being blackened in a short amount of time, and exhibiting an excellent ability to maintain a black appearance after processing. As an original sheet, the sheet used is a Zn-plating steel sheet which contains molten Al and Mg and has a Zn-plating layer containing molten Al and Mg, containing Al in the amount of 0.1-22.0 mass %, inclusive, and containing Mg in the amount of 0.1-1.5 mass %, inclusive. The plating layer is blackened by causing the molten-plating steel sheet to contact water vapor inside a tightly sealed container. When doing so, the concentration of oxygen inside the tightly sealed container is 13% or less.

Abstract: The present invention pertains to a method for producing a black-plated steel sheet capable of being blackened in a short amount of time, and exhibiting an excellent ability to maintain a black appearance after processing. As an original sheet, the sheet used is a Zn-plating steel sheet which contains molten Al and Mg and has a Zn-plating layer containing molten Al and Mg, containing Al in the amount of 1.0-22.0 mass %, inclusive, and containing Mg in the amount of 1.5-10.0 mass %, inclusive. The plating layer is blackened by causing the molten-plating steel sheet to contact water vapor inside a tightly sealed container. When doing so, the concentration of oxygen inside the tightly sealed container is 13% or less.

Abstract: A black-plated steel sheet has a Zn-plating layer containing molten Al and Mg, containing Al in the amount of 1.0-22.0 mass %, containing Mg in the amount of 1.3-10.0 mass %, and having a Zn black oxide distributed in a lamella pattern in the plating layer. The Zn black oxide is a Zn oxide derived from a Zn2Mg phase. The brightness of the surface of the Zn-plating layer containing the molten Al and Mg has an L* value of 60 or less.