Patents by Inventor Noriyuki Koyama

Noriyuki Koyama 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: 4965291
    Abstract: A method of manufacturing a porous membrane by dissolving vinylidene fluoride polymer in a good solvent such as acetone and then causing solidification of the resultant solution in a non-solvent. The dissolution of the vinylidene fluoride polymer in the solvent is done in a predetermined pressure condition, namely 0.1 kg/cm.sup.2, preferably in a range of 0.5 to 5.0 kg/cm.sup.2.
    Type: Grant
    Filed: March 31, 1989
    Date of Patent: October 23, 1990
    Assignee: Terumo Kabushiki Kaisha
    Inventors: Hideaki Kitoh, Yukio Seita, Noriyuki Koyama, Shinsuke Yokomachi
  • Patent number: 4943373
    Abstract: A hydrophilic porous membrane of polyvinylidene fluoride excelling in perviousness to water and other various properties and enjoying high commercial value, having uniform hydropilicity imparted to the surface of pores therein, which porous membrane is characterized by the fact that the reflection spectrum thereof in the visible zone is substantially unchanged from that which existed before the treatment for impartation of hydrophilicity. A method for the production of the hydrophilic porous membrane, characterized by chemically treating the porous membrane in a strong alkali solution containing an oxidizing agent.
    Type: Grant
    Filed: July 12, 1989
    Date of Patent: July 24, 1990
    Assignee: Terumo Kabushiki Kaisha
    Inventors: Makoto Onishi, Yukio Seita, Noriyuki Koyama
  • Patent number: 4776959
    Abstract: A hydrophilic porous membrane comprises a porous membrane made of a hydrophobic polymer and a coating formed on at least one surface of the porous membrane and on the inner surface of pores of the membrane with a water-insoluble hydrophilic polymer soluble in a solvent exhibiting satisfactory stability and a satisfactory wetting property with respect to the hydrophobic polymer and a method for the manufacture of the hydrophilic porous membrane.
    Type: Grant
    Filed: April 13, 1987
    Date of Patent: October 11, 1988
    Assignee: Terumo Corporation
    Inventors: Masaaki Kasai, Noriyuki Koyama
  • Patent number: 4772440
    Abstract: In a method for the manufacture of a porous membrane by the steps of causing a polymer solution to flow and spread in a uniform thickness on a substrate and solidifying the formed layer of the polymer solution in a bad solvent, the improvement which comprises using a fluorinated hydrocarbon as the bad solvent and optionally carrying out the removal of a good solvent mingling into the fluorinated hydrocarbon during the course of the solidification by the technique of extraction from water, and repeating the fluorinated hydrocarbon.
    Type: Grant
    Filed: November 12, 1986
    Date of Patent: September 20, 1988
    Assignee: Terumo Kabushiki Kaisha T/A Terumo Corp.
    Inventors: Masaaki Kasi, Noriyuki Koyama