Patents by Inventor Tazuru Okamoto

Tazuru Okamoto 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: 8945669
    Abstract: The invention provides an extrusion material supply device suitable for use in melt extrusion molding, and a method for manufacturing an optical transmission body, in which a deterioration of an optical signal transmission loss is extremely small, and productivity intrinsic to an extrusion molding method is provided in combination. An extrusion material supply device 1 includes: a vertical hopper 2, which has a cooling unit 3 and a heat melting unit 4 continuous with a lower portion thereof, and houses a material rod R; cooling means 5 for cooling the cooling unit 3; an electric heater 6 that heats the heat melting unit 4; and gas pressurizing means 7 for sequentially supplying molten plastics M to a metal die by a gas pressure. The heat melting unit 4 is formed into a cylinder shape in which an inner diameter is larger than an inner diameter of the cooling unit 3 arranged above, and enables the molten plastics M to spread in the heat melting unit 4.
    Type: Grant
    Filed: January 26, 2010
    Date of Patent: February 3, 2015
    Assignees: Sekisui Chemical Co., Ltd., Keio University
    Inventors: Tazuru Okamoto, Hirotsugu Yoshida, Yasuhiro Koike
  • Patent number: 8611714
    Abstract: [Object] The present invention has the object of providing an optical fiber enabling high-speed communication, that exhibits superior transparency and excellent flexibility, and that includes trichloroethyl methacrylate as a main component of the core portion monomer. [Means for Solving Problem] An optical fiber configured from a core portion and a cladding portion disposed on an outer periphery of the core portion, wherein the core portion is formed by a main constituent component of a polymer of monomers that include at least 70 wt % of trichloroethyl methacrylate (TCEMA), the cladding portion is formed by a main constituent component of a polymer of monomers which include at least 20 wt % of methyl methacrylate (MMA).
    Type: Grant
    Filed: July 5, 2010
    Date of Patent: December 17, 2013
    Assignees: Sekisui Chemical Co., Ltd., Keio University
    Inventors: Hirotsugu Yoshida, Ryosuke Nakao, Hiroka Inabe, Tazuru Okamoto, Yuki Masabe, Masato Aoyama, Yasuhiro Koike
  • Patent number: 8600210
    Abstract: A GI type optical fiber of the present invention is a GI type optical fiber having a core component and a cladding component disposed around the outer periphery of the core component, the core component includes a polymer containing at least 55 wt % chlorostyrene monomer and a dopant, and the cladding component includes a polymer of a monomer containing at least 35 wt % methyl methacrylate. It is an object of the present invention to provide a GI type optical fiber in which chlorostyrene is used as the predominant component of the monomer that constitutes the core component, and therefore has excellent transparency and good flexibility, and allows high-speed communication.
    Type: Grant
    Filed: February 4, 2010
    Date of Patent: December 3, 2013
    Assignees: Sekisui Chemical Co., Ltd., Keio University
    Inventors: Hirotsugu Yoshida, Tazuru Okamoto, Ryosuke Nakao, Hiroka Inabe, Yuki Masabe, Yasuhiro Koike
  • Publication number: 20120114291
    Abstract: [Object] The present invention has the object of providing an optical fiber enabling high-speed communication, that exhibits superior transparency and excellent flexibility, and that includes trichloroethyl methacrylate as a main component of the core portion monomer. [Means for Solving Problem] An optical fiber configured from a core portion and a cladding portion disposed on an outer periphery of the core portion, wherein the core portion is formed by a main constituent component of a polymer of monomers that include at least 70 wt % of trichloroethyl methacrylate (TCEMA), the cladding portion is formed by a main constituent component of a polymer of monomers which include at least 20 wt % of methyl methacrylate (MMA).
    Type: Application
    Filed: July 5, 2010
    Publication date: May 10, 2012
    Inventors: Hirotsugu Yoshida, Ryosuke Nakao, Hiroka Inabe, Tazuru Okamoto, Yuki Masabe, Masato Aoyama, Yasuhiro Koike
  • Publication number: 20120034374
    Abstract: The invention provides an extrusion material supply device suitable for use in melt extrusion molding, and a method for manufacturing an optical transmission body, in which a deterioration of an optical signal transmission loss is extremely small, and productivity intrinsic to an extrusion molding method is provided in combination. An extrusion material supply device 1 includes: a vertical hopper 2, which has a cooling unit 3 and a heat melting unit 4 continuous with a lower portion thereof, and houses a material rod R; cooling means 5 for cooling the cooling unit 3; an electric heater 6 that heats the heat melting unit 4; and gas pressurizing means 7 for sequentially supplying molten plastics M to a metal die by a gas pressure. The heat melting unit 4 is formed into a cylinder shape in which an inner diameter is larger than an inner diameter of the cooling unit 3 arranged above, and enables the molten plastics M to spread in the heat melting unit 4.
    Type: Application
    Filed: January 26, 2010
    Publication date: February 9, 2012
    Applicants: KEIO UNIVERSITY, SEKISUI CHEMICAL CO., LTD.
    Inventors: Tazuru Okamoto, Hirotsugu Yoshida, Yasuhiro Koike
  • Publication number: 20120027369
    Abstract: A GI type optical fiber of the present invention is a GI type optical fiber having a core component and a cladding component disposed around the outer periphery of the core component, the core component includes a polymer containing at least 55 wt % chlorostyrene monomer and a dopant, and the cladding component includes a polymer of a monomer containing at least 35 wt % methyl methacrylate. It is an object of the present invention to provide a GI type optical fiber in which chlorostyrene is used as the predominant component of the monomer that constitutes the core component, and therefore has excellent transparency and good flexibility, and allows high-speed communication.
    Type: Application
    Filed: February 4, 2010
    Publication date: February 2, 2012
    Inventors: Hirotsugu Yoshida, Tazuru Okamoto, Ryosuke Nakao, Hiroka Inabe, Yuki Masabe, Yasuhiro Koike