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:
May. 05, 2020
Filed:
Oct. 18, 2017
Sumitomo Rubber Industries, Ltd., Kobe-shi, Hyogo, JP;
Keiji Ikeda, Kobe, JP;
SUMITOMO RUBBER INDUSTRIES, LTD., Kobe-Shi, Hyogo, JP;
Abstract
Provided are a rubber composition for treads which achieves a balanced improvement in fuel economy, abrasion resistance, and wet grip performance while offering good processability, and a pneumatic tire formed from the rubber composition. The present invention relates to a rubber composition for treads containing: a polybutadiene; and a terpene resin having a glass transition temperature (Tg) of 40° C. to 90° C., the polybutadiene satisfying the following conditions (A), (B) and (C): (A) a ratio (Tcp/ML, 100° C.) of 5% by mass toluene solution viscosity (Tcp) to Mooney viscosity (ML, 100° C.) is 0.9 to 2.3; (B) a stress relaxation time (T80) is 10.0 to 40.0 seconds, which is a time required for torque to decay by 80%, where 100% represents torque at the end of a ML, 100° C. measurement; and (C) a molecular weight distribution (Mw/Mn) is 2.50 to 4.00.