Patents by Inventor Naomichi Kitsugi

Naomichi Kitsugi 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).

  • Patent number: 4457901
    Abstract: SiF.sub.4 gas containing oxygen-containing silicofluoride(s) typified by (SiF.sub.3).sub.2 O as impurity can be refined to extremely high purity by making the SiF.sub.4 gas contact with HF in the presence of a liquid medium having strong affinity for water such as sulfuric acid or phosphoric acid. By reaction with HF, the impurity such as (SiF.sub.3).sub.2 O is converted to SiF.sub.4, while the liquid medium absorbs water formed by the reaction to thereby prevent a reverse reaction between SiF.sub.4 and H.sub.2 O to form (SiF.sub.3).sub.2 O.
    Type: Grant
    Filed: August 5, 1982
    Date of Patent: July 3, 1984
    Assignee: Central Glass Company, Limited
    Inventors: Naomichi Kitsugi, Teruo Fujinaga, Toyozo Otsuka
  • Patent number: 4382071
    Abstract: A process of preparing silicon tetrafluoride by introducing hydrogen fluoride gas into a dispersion of powdery silicon oxide material, which needs not to be pure SiO.sub.2, in sulfuric acid not lower than 65% in the concentration of H.sub.2 SO.sub.4. The reaction takes place even at room temperature. By using amorphous silicon oxide material, the rate of reaction can be enhanced with better yield. Preferably, the concentration of H.sub.2 SO.sub.4 in the liquid phase of the reaction system is maintained above 80% to obtain SiF.sub.4 containing little (SiF.sub.3).sub.2 O.
    Type: Grant
    Filed: July 1, 1981
    Date of Patent: May 3, 1983
    Assignee: Central Glass Company, Limited
    Inventors: Toyozo Otsuka, Naomichi Kitsugi, Teruo Fujinaga