The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 30, 1991
Filed:
Dec. 06, 1989
Fumio Tsutsumi, Yokkaichi, JP;
Akihiko Morikawa, Tsu, JP;
Mitsuhiko Sakakibara, Yokkaichi, JP;
Noboru Oshima, Suzuka, JP;
Tatsuro Hamada, Higashimurayama, JP;
Tatsuo Fujimaki, Higashimurayama, JP;
Masayuki Ohashi, Suginami, JP;
Japan Synthetic Rubber Co., Tokyo, JP;
Bridgestone Corp., Tokyo, JP;
Abstract
A rubber composition is disclosed which contains not less than 20% by weight in a rubber component of a block copolymer composed of polymer or copolymer block units (A) and a random copolymer block units (B). The polymer or copolymer block units (A) are obtained by singly polymerizing a conjugated diolefine or copolymerizing the conjugated diolefine and a monovinyl aromatic hydrocarbon with use of a lithium initiator and contains not more than 10% by weight of the bound monovinyl aromatic hydrocarbon. The random copolymer block unit (B) are obtained by copolymerizing the conjugated diolefine and the monovinyl aromatic hydrocarbon and contain 15 to 80% by weight of the bound monovinyl aromatic hydrocarbon. In the block copolymer, (i) the block copolymer contains not less than 10% by weight of each of the block units (A) and the block units (B); (ii) the total content of the bound monovinyl aromatic hydrocarbon is from 10 to 40% by weight; (iii) the average content of the vinyl bonds in the conjugated diolefine portions is from 20 to 70%; and (iv) polymerizable terminals of the block copolymer are reacted with an isocyanate compound.