MUMBAI, India, Aug. 22 -- Intellectual Property India has published a patent application (202517054261 A) filed by Jfe Steel Corporation, Tokyo, on June 5, for 'surface-treated steel sheet.'
Inventor(s) include Tsuchimoto Kazuaki; and Matsuda Takeshi.
The application for the patent was published on Aug. 22, under issue no. 34/2025.
According to the abstract released by the Intellectual Property India: "Provided is a surface-treated steel sheet in which chromium is not contained in a surface-treating film and which is excellent in terms of both post-processing corrosion resistance and spot weldability. The surface-treated steel sheet according to the present invention is characterized by comprising: a zinc-based plated steel sheet having, on a surface thereof, micro recesses and protrusions; an organic-inorganic composite film formed on the surface of the zinc-based plated steel sheet and not containing chromium; and a surface-treating film formed on the organic-inorganic composite film and comprising a polyurethane resin. The surface-treated steel sheet is also characterized in that: in the protruding parts in the zinc-based plated steel sheet, the average of the total thicknesses of the organic-inorganic composite film and the surface-treating film is 0.10 m or less; the average thickness of the surface-treating film is 0.4 to 1.0 m; and, after the surface-treated steel sheet is subjected to bending/restoration processing by using a bead having a tip diameter of 5 mmR, the film damage rate of the surface-treating film is 20% or less."
The patent application was internationally filed on Jan. 30, 2024, under International application No.PCT/JP2024/002920.
Disclaimer: Curated by HT Syndication.
