Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Fumio Shibao

Takashi Fujii

Kohei Ueda

Akira Nakagawa

Hiroyasu Furukawa

Yuki Yamamura

Naoto Sasaki

Masayoshi Nagatomi

Kiyokazu Ishizuka

Masahiro Fuda

Hidetoshi Shindo

Ikuo Kikuchi

Taihei Kaneto

Takashi Futaba

Hiroaki Uramoto

Yoshio Kimata

Katsuhide Soya

Keita Katsumaru

To further improve, even under OT bending with the use of a Zn—Al—Mg-based alloy plated steel sheet as a base sheet, corrosion resistance regarding corrosion under paint film at a OT bent portion and a periphery thereof, without causing occurrence of cracks and peeling in the paint film. A pre-coated plated steel sheet according to the present invention includes: a plating layer composed of Zn—Al—Mg-based alloy plating, the plating layer being positioned on one side or both sides of a steel sheet; a chemical treatment film layer positioned on the plating layer; and a paint film layer positioned on the chemical treatment film, in which the paint film layer includes a primer paint film layer, and an upper paint film layer positioned on the primer paint film layer, and at least any of the following is satisfied: both a condition (a-1) and a condition (a-2); a condition (b); and a condition (c).

Pre-coated plated steel sheet and molded product

To more securely inhibit the occurrence of paint film floating even when drawing is performed by using a Zn—Al—Mg-based alloy plated steel sheet as a base sheet. A pre-coated plated steel sheet according to the present invention includes: a plating layer composed of Zn—Al—Mg-based alloy plating, the plating layer being positioned on one side or both sides of a steel sheet; a chemical treatment film layer positioned on the plating layer; and a paint film layer positioned on the chemical treatment film, in which the paint film layer includes a primer paint film layer, and an upper paint film layer positioned on the primer paint film layer, and at least any of the following is satisfied: both a condition (a-1) and a condition (a-2); a condition (b); and a condition (c).

The present invention provides a noble and improved organic resin-coated plated steel sheet which is improved in degreasing properties while securing the characteristics required for the organic resin-coated plated steel sheet. In order to solve the problems, according to one aspect of the present invention, there is provided an organic resin-coated plated steel sheet comprising: a metal coated steel sheet; an organic resin coating covering the metal coated steel sheet; and beads dispersed in the organic resin coating, in which the organic resin coating includes a polyester having a glass transition temperature of 0&#xb0; C. to 20&#xb0; C., and a melamine-formaldehyde, the beads are urethane beads having a glass transition temperature of &#x2212;60&#xb0; C. to 50&#xb0; C., are contained in the organic resin coating at a ratio of 1 to 15 mass % to the total mass of the organic resin coating, and are dispersed in the organic resin coating at an area density of 5 to 1000 pieces/mm, and relationships of Formulas (1) to (3) are satisfied.

Organic resin-coated plated steel sheet

A plated steel includes: a steel; a zinc based electroplated layer formed on a surface of the steel; and an organic resin coating layer formed on a surface of the zinc based electroplated layer, in which the surface of the zinc based electroplated layer has hairline extending in a predetermined direction, Ra (ML) measured on the surface of the zinc based electroplated layer is 0.10 to 0.70 &#x3bc;m, on the surface of the zinc based electroplated layer, a peak number PPI measured in a hairline orthogonal direction with a reference level of 10 &#x3bc;inch satisfies PPI&#x2265;350&#xd7;Ra (MC) with respect to Ra (MC), on a surface of the organic resin coating layer, Ra (CC) satisfies Ra (CC)/Ra (CL)&#x2265;1.10 with respect to Ra (CL), and Ra (CC) satisfies Ra (CC)&#x3c;Ra (MC) with respect to Ra (MC).

Plated steel

A device for producing a coated steel sheet includes: a blowing-off unit which sprays a gas onto and remove an excessive coating that accumulates along a side edge of a steel sheet that threads along one direction; and a coating-collection unit which collects the excessive coating removed by the blowing-off unit. The blowing-off unit includes a spray nozzle and a gas supply member. The coating-collection unit includes a duct and a coating container. In a case where the duct is seen in a plan view, an outlet thereof is disposed to fit in and overlap an inside of an opening of the coating container, and in a case where the duct is seen in a side view, a gap is provided between the outlet and the opening of the coating container.

Device for producing coated steel sheet and method for producing coated steel sheet

A surface-treated steel sheet includes: a steel sheet; and a coated layer which is formed on one surface or both surfaces of the steel sheet and includes zinc and vanadium, wherein the coated layer has a vanadium content of 1% or higher and 20% or less and a coating weight of 3 g/mor higher and 40 g/mor less, and has a plurality of dendritic arms that are grown in a thickness direction of the steel sheet, and a ratio x/y of a content x of vanadium that is present outside the arms to a content y of vanadium that is present inside the arms is 1.1 or higher and 3.0 or less in terms of vanadium element.

Surface-treated steel sheet and method of manufacturing the same

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Tokyo, Japan

Fumio Shibao