Patents by Inventor Yoshiro Uchiyama

Yoshiro Uchiyama 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).

  • Process for separating and purifying alkali metal salts of hydroxynaphthalenecarboxylic acids
    Patent number: 6194608
    Abstract: The present invention provides a process for separating and purifying alkali metal salts of hydroxynaphthalenecarboxylic acids, in which alkali metal salt(s) of hydroxynaphthalenecarboxylic acid(s) are separated and purified from a mixture of alkali metal salts of hydroxynaphthalenecarboxylic acids by treating it with a nonionic porous synthetic adsorbent using water or water and water-soluble organic solvent(s).
    Type: Grant
    Filed: November 19, 1998
    Date of Patent: February 27, 2001
    Assignee: Kabushiki Kaisha Veno Seiyaku Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Kuniyo Yanagawase, Yoshiro Uchiyama, Shigeji Mori
  • Process for producing 2-hydroxynaphthalene-3,6-dicarboxylic acid
    Patent number: 6133475
    Abstract: The present invention relates to a process for preparing 2-hydroxynaphthalene-3,6-dicarboxylic acid which comprises reacting potassium 2-naphtholate and carbon dioxide at a temperature 290.degree. C. or higher under a pressure 30 kg/cm.sup.2 (G) or higher. According to this process, 2-hydroxynaphthalene-3,6-dicarboxylic acid can be obtained in high yield.
    Type: Grant
    Filed: June 16, 1998
    Date of Patent: October 17, 2000
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Yoshiro Uchiyama, Syungo Nara
  • Method for separating and purifying hydroxynaphtalenecarboxylic acids
    Patent number: 5770766
    Abstract: The present invention provides a method for effectively separating independent hydroxynaphthalene-carboxylic acids by treating a mixture containing various kinds of hydroxynaphthalene-carboxylic acids with nonionic porous synthetic adsorbents having as a basic structure aromatic copolymers mainly composed of styrene and divinyl benzene or methacryl copolymers mainly composed of monomethacrylates and dimethacrylates.
    Type: Grant
    Filed: July 10, 1997
    Date of Patent: June 23, 1998
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
    Inventors: Ryuzo Ueno, Masaya Kitayama, Kuniyo Yanagawase, Yoshiro Uchiyama, Shigeji Mori