Patents by Inventor Shigeru Tomihira

Shigeru Tomihira 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).

  • Polybutadiene rubber compositions having improved green strength
    Patent number: 4533711
    Abstract: A polybutadiene rubber composition having an improved green strength is disclosed, which comprises a polybutadiene having a content of cis-1,4 bond of at least 70%, an average chain length of 1,4-bond of 110.about.450 and a molecular weight distribution represented by a ratio of weight-average molecular weight to number-average molecular weight of not less than 5.0.
    Type: Grant
    Filed: September 7, 1983
    Date of Patent: August 6, 1985
    Assignees: Bridgestone Tire Company Limited, Japan Synthetic Rubber Co., Ltd.
    Inventors: Yasumasa Takeuchi, Mitsuhiko Sakakibara, Nobuo Tagata, Masaki Ogawa, Yasushi Hirata, Shigeru Tomihira
  • Rubber compositions
    Patent number: 4515922
    Abstract: A rubber composition having improved wet skid resistance and rolling resistance is disclosed, which comprises (A) 10-90% by weight of polybutadiene rubber having a content of cis-1,4-bond at least 80% and an average chain length of cis-1,4-bond of not less than 110, and (B) 10-90% by weight of random styrene-butadiene copolymer rubber obtained by copolymerization in the presence of an organic metal catalyst and having a content of bound styrene of not more than 40% by weight and a content of 1,2-bond in total butadiene unit of 30-95%.
    Type: Grant
    Filed: January 27, 1984
    Date of Patent: May 7, 1985
    Assignees: Bridgestone Tire Company Limited, Japan Synthetic Rubber Co., Ltd.
    Inventors: Mitsuhiko Sakakibara, Masao Yoshizawa, Masaki Ogawa, Yasushi Hirata, Shigeru Tomihira
  • Polybutadiene rubber compositions
    Patent number: 4468496
    Abstract: A rubber composition having excellent fracture properties and cut growth resistance is disclosed, which consists of 10-95 parts by weight of polybutadiene having a content of cis-1,4 bond of at least 70% and an average chain length of 1,4-sequence of 110-450 and 90-5 parts by weight of at least one diene rubber.
    Type: Grant
    Filed: July 26, 1982
    Date of Patent: August 28, 1984
    Assignees: Bridgestone Tire Co., Ltd., Japan Synthetic Rubber Co., Ltd.
    Inventors: Yasumasa Takeuchi, Mitsuhiko Sakakibara, Nobuo Tagata, Masaki Ogawa, Yasushi Hirata, Shigeru Tomihira
  • Polyisoprene rubber compositions
    Patent number: 4433107
    Abstract: A rubber composition having improved cut growth resistance, processability and dimensional stability is disclosed, which comprises not less than 20 parts by weight of polyisoprene having a melting point of not less than 10.degree. C. and a content of cis-1,4 bond of not less than 88% and the balance of at least one diene rubber.
    Type: Grant
    Filed: August 3, 1982
    Date of Patent: February 21, 1984
    Assignee: Bridgestone Tire Co., Ltd.
    Inventors: Yasumasa Takeuchi, Mitsuhiko Sakakibara, Nobuo Tagata, Masaki Ogawa, Yasushi Hirata, Shigeru Tomihira