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:
Oct. 29, 2002
Filed:
Mar. 27, 1997
Bridgestone Corporation, Tokyo, JP;
Abstract
A styrene-butadiene copolymer having excellent low hysteresis loss characteristic, wet skid resistance, fracture characteristics, and abrasion resistance and a rubber composition comprising the copolymer are disclosed. The styrene-butadiene copolymer has a total styrene content in the range of 33 to 42% by weight of the styrene-butadiene copolymer; a content of styrene sequences having 4 to 20 styrene units in the range of 40 to 65% by weight of the total styrene content, as obtained by measurements by NMR and GPC; a content of styrene sequences having more than 20 styrene units in the range of 5% by weight or less of the total styrene content, as obtained by measurement by GPC; a content of vinyl unit in the range of 30% by mol or less of a butadiene part of the styrene-butadiene copolymer; a sum of the total styrene value and ½ of the content of vinyl units in the range of 46 to 52%; and an inner or end structure having, for example tin-carbon bond. The copolymer and the rubber composition are used for tire treads and the like.