Patents by Inventor Takahiro Nagayama

Takahiro Nagayama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Metal surface-treating method
    Patent number: 6458219
    Abstract: This invention provides a metal surface-treating method which comprises a chemical conversion step of dipping a substrate in an acidic aqueous zinc phosphate solution, and using an aqueous zinc nitrite solution as an accelerator, said aqueous zinc nitrite solution being substantially free of calcium ion and containing 0 to 6500 ppm of sodium ion and 0 to 20 ppm of sulfate ion in case of assuming the concentration of zinc nitrite [Zn(NO2)2] therein to be 10 weight % as NO2.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: October 1, 2002
    Assignees: Nippon Paint Co., Ltd., Nippon Chemical Industrial Co., Ltd.
    Inventors: Hiroshi Chihara, Kenji Tsuge, Yutaka Kinose, Toru Hata, Eriko Okuno, Takahiro Nagayama
  • Metal surface-treating method
    Publication number: 20020008226
    Abstract: This invention provides a metal surface-treating method
    Type: Application
    Filed: May 14, 2001
    Publication date: January 24, 2002
    Inventors: Hiroshi Chihara, Kenji Tsuge, Yutaka Kinose, Toru Hata, Eriko Okuno, Takahiro Nagayama
  • Aqueous zinc nitrite solution and method for preparing the same
    Publication number: 20020001559
    Abstract: An aqueous zinc nitrite solution contains as impurities 10 ppm or less of sodium (Na) and 100 ppm or less of sulfate ions (SO4) when the aqueous solution has a concentration of zinc nitrite [Zn(NO2)2] of 10% by weight in terms of NO2. Also, disclosed is a method for preparing an aqueous zinc nitrite solution, including a first step of reacting zinc sulfate with calcium nitrite to form an aqueous zinc nitrite solution and a second step of purifying the aqueous zinc nitrite solution.
    Type: Application
    Filed: May 15, 2001
    Publication date: January 3, 2002
    Inventors: Yutaka Kinose, Takahiro Nagayama, Toru Hata
  • Rust-preventive pigment composition and rust-preventive paints containing the same
    Patent number: 6139616
    Abstract: The present invention relates to an anti-corrosive pigment composition, characterized by comprising, as main components, white anti-corrosive pigment and an inorganic anion exchanger represented by the following formula (1):(3-4)[M.sub.1 ]O.Al.sub.2 O.sub.3.[M.sub.2 ]X.sub.2/m .multidot.nH.sub.2 O(1)(wherein, M.sub.1 and M.sub.2 are at least one selected from Ca.sup.2+ or Zn.sup.2+, X represents at least one anion selected from NO.sub.2.sup.-, NO.sub.3.sup.- or MoO.sub.4.sup.2-, m represents a valency of the anion, and n is 20 or less).
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: October 31, 2000
    Assignees: Nippon Chemical Industrial Co., LTD, Toho Ganryo Kogyo Co., Ltd.
    Inventors: Takahiro Nagayama, Minoru Yokoyama