Patents by Inventor Nabuyuki Yoshida

Nabuyuki Yoshida 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).

  • Rubber composition for tire treads containing dicarboxylic acid diester coupled block polymers
    Patent number: 4812527
    Abstract: A rubber composition suitable for tire treads having well-balanced excellent wet skid characteristic, ice skid characteristic and rolling characteristic, and an excellent processability, which comprises a rubber component containing at least 20% by weight of a block copolymer consisting essentially of a block A and a block B, obtained by conducting polymerization of an aromatic vinyl compound and a conjugated diene compound in a hydrocarbon solvent in the presence of an organolithium initiator and modifying with a coupling agent, and satisfying the following conditions (A) to (E);(A) the block A having a content of an aromatic vinyl compound of at most 5% by weight and a content of 1,2-bonds in the conjugated diene component of at least 10% by weight,(B) the block B having a content of an aromatic vinyl compound of 25 to 50% by weight and a content of 1,2-bonds in the conjugated diene component of at least 10% by weight,(C) a content of the block A in the block copolymer being from 20 to 80% by weight,(D) a c
    Type: Grant
    Filed: October 27, 1987
    Date of Patent: March 14, 1989
    Assignees: Sumitomo Chemical Company, Limited, Sumitomo Rubber Industries, Ltd.
    Inventors: Hiroyoshi Takao, Nabuyuki Yoshida, Akio Imai, Mitsuji Tsuji, Yuichi Saito