Patents by Inventor Ryota Tokura

Ryota Tokura 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: 7015263
    Abstract: A process for recovering fluoropolymers, which comprises contacting an ion exchange membrane comprising a fluoropolymer having carboxylic acid groups (hereinafter referred to as a C-polymer) and a fluoropolymer having sulfonic acid groups (hereinafter referred to as a S-polymer) and having inorganic particles deposited on the surface, with a solvent to let it swell and to remove the inorganic particles from the surface, then, contacting it with a solvent which is a good solvent for the S-polymer and a poor solvent for the C-polymer to obtain a solid composed mainly of the C-polymer and a solution having the S-polymer dissolved therein, and recovering them by solid-liquid separation.
    Type: Grant
    Filed: March 6, 2002
    Date of Patent: March 21, 2006
    Assignee: Asahi Glass Company, Limited
    Inventors: Seisaku Kumai, Yutaka Fukatsu, Ryota Tokura
  • Patent number: 6515102
    Abstract: A process for recovering fluoropolymers, which comprises contacting an ion exchange membrane comprising a fluoropolymer having carboxylic acid groups (hereinafter referred to as a C-polymer) and a fluoropolymer having sulfonic acid groups (hereinafter referred to as a S-polymer) and having inorganic particles deposited on the surface, with a solvent which is a good solvent for the C-polymer and a good solvent for the S-polymer, to separate a solution having the C-polymer and the S-polymer dissolved therein, and the inorganic particles, then esterifying the C-polymer in the solution to form precipitate of an ester of the C-polymer, and fractionating and recovering the precipitate and a solution having the S-polymer dissolved therein by solid-liquid separation.
    Type: Grant
    Filed: March 8, 2002
    Date of Patent: February 4, 2003
    Assignees: Asahi Glass Company, Limited, Seimi Chemical Co., Ltd.
    Inventors: Seisaku Kumai, Yutaka Fukatsu, Harumi Mihara, Ryota Tokura
  • Publication number: 20020128430
    Abstract: A process for recovering fluoropolymers, which comprises contacting an ion exchange membrane comprising a fluoropolymer having carboxylic acid groups (hereinafter referred to as a C-polymer) and a fluoropolymer having sulfonic acid groups (hereinafter referred to as a S-polymer) and having inorganic particles deposited on the surface, with a solvent which is a good solvent for the C-polymer and a good solvent for the S-polymer, to separate a solution having the C-polymer and the S-polymer dissolved therein, and the inorganic particles, then esterifying the C-polymer in the solution to form precipitate of an ester of the C-polymer, and fractionating and recovering the precipitate and a solution having the S-polymer dissolved therein by solid-liquid separation.
    Type: Application
    Filed: March 8, 2002
    Publication date: September 12, 2002
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Seisaku Kumai, Yutaka Fukatsu, Harumi Mihara, Ryota Tokura
  • Publication number: 20020128335
    Abstract: A process for recovering fluoropolymers, which comprises contacting an ion exchange membrane comprising a fluoropolymer having carboxylic acid groups (hereinafter referred to as a C-polymer) and a fluoropolymer having sulfonic acid groups (hereinafter referred to as a S-polymer) and having inorganic particles deposited on the surface, with a solvent to let it swell and to remove the inorganic particles from the surface, then, contacting it with a solvent which is a good solvent for the S-polymer and a poor solvent for the C-polymer to obtain a solid composed mainly of the C-polymer and a solution having the S-polymer dissolved therein, and recovering them by solid-liquid separation.
    Type: Application
    Filed: March 6, 2002
    Publication date: September 12, 2002
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Seisaku Kumai, Yutaka Fukatsu, Ryota Tokura