Patents Assigned to Tatsuya Miyoshi
  • Publication number: 20010001965
    Abstract: In order to manufacture a chromate-coated lead-containing galvanized steel sheet having beautiful spangles and excellent anti-black patina and anti-white rust properties without relying upon any flushing treatment with Ni, etc., a lead-containing galvanized steel sheet obtained by plating in a galvanizing bath containing appropriate amounts of Pb and Al, and having beautiful spangles is coated with a chromate coating solution containing trivalent and hexavalent chromium ions in a molar ratio of 1/9 to 1/1, and nitrate ions in a molar ratio of 0.1 to 1.6 to the total of the chromium ions, preferably after treatment with an aqueous alkali solution having a pH of 9 or above, and washing with water, and the sheet is dried at an appropriate sheet temperature without being washed with water, whereby a chromate film having a coating weight of 5 to 50 mg/m2 is formed thereon.
    Type: Application
    Filed: March 23, 1998
    Publication date: May 31, 2001
    Applicant: Tatsuya Miyoshi
    Inventors: TATSUY MIYOSHI, TAKAHIRO KUBOTA, MASARU SAGIYAMA, YOSHIHARU SUGIMOTO, MASAAKI YAMASHITA