Patents by Inventor Shouzou Kaneda

Shouzou Kaneda 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).

  • Method of purifying 4-fluorophenol
    Patent number: 4523041
    Abstract: A method of efficiently purifying crude 4-fluorophenol containing phenol as impurity. Phthalic acid or its anhydride, or a suitable derivative of phthalic acid, and a dehydrating agent such as sulfuric acid or a metal chloride are mixed with the crude 4-fluorophenol, and the mixture is kept in a liquid state usually with moderate heating to 30.degree.-180.degree. C. until completion of condensation reaction between phenol and the phthal-compound. After that pure 4-fluorophenol can easily be recovered by distillation or recrystallization.
    Type: Grant
    Filed: May 25, 1984
    Date of Patent: June 11, 1985
    Assignee: Central Glass Company, Limited
    Inventors: Toshikazu Kawai, Haruo Suzuki, Shouzou Kaneda