Patents by Inventor Junji Kojina

Junji Kojina 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: 6930146
    Abstract: A polymer composition and a thermoplastic elastomer composition containing 1,2-polybutadiene having a 1,2-bond content in the butadiene unit of 70% by weight or more, a melting point in the range of 50 to 140° C., a total halogen content of 30 ppm or less, a viscosity ? in the range of 400 to 1200 poise when measured with a slit die rheometer at a shear rate of 5113 sec?1 at 120° C., a viscosity ? in the range of 300 to 1000 poise when measured with a slit die rheometer at a shear rate of 5113 sec?1 at 150° C., and a viscosity ? in the range of 200 to 800 poise when measured with a slit die rheometer at a shear rate of 5113 sec?1 at 180° C. exhibit excellent moldability, visual appearance and scratch resistance.
    Type: Grant
    Filed: July 27, 2000
    Date of Patent: August 16, 2005
    Assignee: JSR Corporation
    Inventors: Koji Okada, Masato Suzuki, Junji Kojina
  • Patent number: 5504156
    Abstract: A thermoplastic elastomer composition which comprises (I) 99 to 1% by weight of a hydrogenated diene copolymer having a number average molecular weight of 50000 to 700,000 in which 80% or more of the double bonds of the conjugated diene portion of the conjugated diene polymer have been saturated, (II) 1 to 99% by weight of an ionomer resin having an .alpha.-olefin unit having 2 to 8 carbon atoms and an .alpha.,.beta.-unsaturated carboxylic acid unit, at least part of the carboxyl group of said unsaturated carboxylic acid unit having been neutralized with a metal ion, and (III) 0 to 70% by weight of a polyolefin resin, provided that (I)+(II)+(III)=100% by weight. Said composition is excellent in moldability and gives a molded article excellent in transparency, flexibility, mechanical strength, heat resistance and impact resilience.
    Type: Grant
    Filed: December 14, 1994
    Date of Patent: April 2, 1996
    Assignee: Japan Synthetic Rubber Co., Ltd.
    Inventors: Yoshiyuki Takezaki, Junji Kojina, Kazumi Nejigaki, Yoshihisa Fujinaga
  • Patent number: 5306770
    Abstract: A thermoplastic resin composition which comprises:(A) 45-90% by weight of a rubber-modified thermoplastic styrene resin in which the grafting degree is 40-150% by weight based on the weight of the rubbery polymer,(B) 9.5-54.5% by weight of an aromatic polyester having an intrinsic viscosity of 1.1-2 dl/g as measured at 25.degree. C. in o-chlorophenol, and(C) 0.1-20% by weight of a graft copolymer obtained by graft-copolymerizing a monomer mixture consisting of 60-80% by weight of an aromatic alkenyl compound and 20-40% by weight of an alkenyl cyanide compound on a copolymer consisting essentially of an olefin unit and an epoxy group-containing unsaturated compound unit, and(D) optionally a silicone lubricant in a proportion of 5-20,000 ppm of the total weight of the (A), (B) and (C) components.
    Type: Grant
    Filed: October 4, 1991
    Date of Patent: April 26, 1994
    Assignee: Japan Synthetic Rubber Co., Ltd.
    Inventors: Junji Kojina, Akio Matsuda, Yasunori Asano, Tateki Furuyama