Patents by Inventor Tatsutoshi Nakashima

Tatsutoshi Nakashima 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).

  • Contact lens material
    Patent number: 4814402
    Abstract: A contact lens material composed of a copolymer of a monomer mixture comprising, as essential monomers, from 5 to 20 parts by weight, based on 100 parts by weight of the total monomer mixture, of a hydrophilic monomer consisting of from 40 to 60 mol % of N-vinyl-2-pyrrolidone and from 40 to 60 mol % of metharylic acid and from 30 to 95 parts by weight, based on 100 parts by weight of the total monomer mixture, of at least one of a silicon-containing acrylate and a silicon-containing methacrylate.
    Type: Grant
    Filed: November 12, 1987
    Date of Patent: March 21, 1989
    Assignee: Menicon Co., Ltd.
    Inventors: Tatsutoshi Nakashima, Yoshitaka Taniyama, Akihisa Sugiyama
  • Highly water-absorptive optical material
    Patent number: 4745158
    Abstract: A highly water-absorptive optical material obtained by saponification for hydrophilic treatment of a copolymer composed essentially of:(A) from 2 to 30 parts by weight of a (meth)acrylate polymer having at least one polymerizable group per molecule on an average obtained by copolmerizing (a) at alkyl (meth)acrylate monomer and (b) a monomer having at least two polymerizable groups per molecule, as the main components, and(B) from 70 to 98% by weight of a fatty acid vinyl ester.
    Type: Grant
    Filed: April 21, 1987
    Date of Patent: May 17, 1988
    Assignee: Toyo Contact Lens Co., Ltd.
    Inventors: Tatsutoshi Nakashima, Nobuyuki Toyoshima, Yasuomi Sasai