Patents by Inventor Yoichi Takenaka

Yoichi Takenaka 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).

  • Preparation method for perfluoroalkane sulfinate
    Patent number: 9073828
    Abstract: In a method for obtaining an alkali metal perfluoroalkanesulfinate by reacting a perfluoroalkanesulfonyl halide with a sulfur-containing reducing agent in the presence of water, a reaction liquid containing the alkali metal sulfinate obtained after the reaction is concentrated till a specific concentration, thereby inorganic salts, which are impurities in the solution, are precipitated and removed, and a filtrate after removing the inorganic salts is subjected to an operation such as concentration and drying, thereby obtaining the target alkali metal perfluorosulfinate with a high purity and a good operability. Furthermore, an organic solvent for extraction becomes unnecessary. Therefore, it is possible to greatly reduce wastes.
    Type: Grant
    Filed: March 3, 2011
    Date of Patent: July 7, 2015
    Assignee: Central Glass Company, Limited
    Inventors: Takashi Kashiwaba, Tsutomu Nanmyo, Yoichi Takenaka
  • Preparation Method for Perfluoroalkane Sulfinate
    Publication number: 20130023695
    Abstract: In a method for obtaining an alkali metal perfluoroalkanesulfinate by reacting a perfluoroalkanesulfonyl halide with a sulfur-containing reducing agent in the presence of water, a reaction liquid containing the alkali metal sulfinate obtained after the reaction is concentrated till a specific concentration, thereby inorganic salts, which are impurities in the solution, are precipitated and removed, and a filtrate after removing the inorganic salts is subjected to an operation such as concentration and drying, thereby obtaining the target alkali metal perfluorosulfinate with a high purity and a good operability. Furthermore, an organic solvent for extraction becomes unnecessary. Therefore, it is possible to greatly reduce wastes.
    Type: Application
    Filed: March 3, 2011
    Publication date: January 24, 2013
    Applicant: CENTRAL GLASS COMPANY, LIMITED
    Inventors: Takashi Kashiwaba, Tsutomu Nanmyo, Yoichi Takenaka