Steel sheet and production method therefor

Patent metadata

Field	Value
Publication number	US-2024400851-A1
Application number	US-202218698095-A
Country	US
Kind code	A1
Filing date	Jun 17, 2022
Priority date	Oct 14, 2021
Publication date	Dec 5, 2024
Grant date	—

Abstract

A lubricating film-coated steel sheet to be subjected to complicated forming is disclosed. The organic resin film contains an acrylic resin having a glass transition point (Tg) of 100° C. or higher and an acid value ratio R=acid value (mg-KOH/g)/Tg (° C.) of 1.50 or more, and 5 mass % or more of a polyolefin wax having a melting point of 100° C. or higher and 145° C. or lower and an average particle diameter of 3.0 μm or less, and is formed on a surface of a steel sheet at a coating weight, W, of 0.3 g/m 2 or more and 2.5 g/m 2 or less per surface.

First claim

1 - 14 . (canceled)

15 . A steel sheet having at least one surface on which a film containing an acrylic resin and a wax is formed, wherein the acrylic resin has a glass transition point (Tg) of 100° C. or higher and an acid value-to-glass transition point ratio R=acid value (mg-KOH/g)/Tg (° C.) of 1.50 or more, the wax is a polyolefin wax that has a melting point of 100° C. or higher and 145° C. or lower and an average particle diameter of 3.0 μm or less, a proportion of the wax in the film is 5 mass % or more, and a coating weight W of the film per surface is 0.3 g/m 2 or more and 2.5 g/m 2 or less.

16 . The steel sheet according to claim 15 , wherein the acid value of the acrylic resin is 180 mg-KOH/g or more and 350 mg-KOH/g or less.

17 . The steel sheet according to claim 15 , wherein the acid value-to-glass transition point ratio R of the acrylic resin is 2.05 or less.

18 . The steel sheet according to claim 15 , wherein the film contains 30 mass % or more of the acrylic resin, and the proportion of the wax is 50 mass % or less.

19 . The steel sheet according to claim 15 , wherein the acrylic resin has a mass-average molecular weight of 5000 or more and 30000 or less.

20 . The steel sheet according to claim 15 , wherein the acrylic resin is a styrene acrylic resin.

21 . The steel sheet according to claim 15 , wherein the steel sheet before formation of the film has an arithmetic mean roughness Ra of 0.4 μm or more and 2.5 μm or less.

22 . The steel sheet according to claim 15 , wherein the film contains 5 mass % or more and 30 mass % or less of an antirust agent.

23 . The steel sheet according to claim 15 , wherein the wax has an average particle diameter of 0.01 μm or more and 0.5 μm or less.

24 . The steel sheet according to claim 15 , wherein the film contains 1 mass % or more and 10 mass % or less of silica.

25 . A method for producing the steel sheet according to claim 15 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 15 , and drying the applied coating solution.

26 . A method for producing the steel sheet according to claim 16 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 16 , and drying the applied coating solution.

27 . A method for producing the steel sheet according to claim 17 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 17 , and drying the applied coating solution.

28 . A method for producing the steel sheet according to claim 18 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 18 , and drying the applied coating solution.

29 . A method for producing the steel sheet according to claim 19 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 19 , and drying the applied coating solution.

30 . A method for producing the steel sheet according to claim 20 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 20 , and drying the applied coating solution.

31 . A method for producing the steel sheet according to claim 21 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 21 , and drying the applied coating solution.

32 . A method for producing the steel sheet according to claim 22 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 22 , and drying the applied coating solution.

33 . A method for producing the steel sheet according to claim 23 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 23 , and drying the applied coating solution.

34 . A method for producing the steel sheet according to claim 24 , the method comprising applying, to at least one surface of a steel sheet, a coating solution that contains the acrylic resin and the wax according to claim 24 , and drying the applied coating solution.

Assignees

• Jfe Steel Corp

Inventors

• Furuya Shinichi
• Matsuda Takeshi
• Aoyama Tomohiro
• KOIBUCHI Shun

Classifications

• C09D191/06

  Waxes · CPC title

• C09D5/08

  Anti-corrosive paints · CPC title

• B05D2701/00

  Coatings being able to withstand changes in the shape of the substrate or to withstand welding · CPC title

• B05D2507/01

  Polyethylene · CPC title

• B05D2502/00

  Acrylic polymers · CPC title