US 12,251,965 B2
Tire tread rubber composition
Anthony M. Unger, New Albany, OH (US); Adrian C. Stalnaker, Cuyahoga Falls, OH (US); Jessica L. Placke, Rocky River, OH (US); and Benjamin C. Galizio, Munroe Falls, OH (US)
Assigned to Bridgestone Americas Tire Operations, LLC, Nashville, TN (US)
Filed by Bridgestone Americas Tire Operations, LLC, Nashville, TN (US)
Filed on Jun. 10, 2021, as Appl. No. 17/344,080.
Application 17/344,080 is a continuation of application No. 17/052,723, previously published as PCT/US2019/030170, filed on May 1, 2019.
Claims priority of provisional application 62/667,108, filed on May 4, 2018.
Prior Publication US 2021/0300118 A1, Sep. 30, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. B60C 1/00 (2006.01); C08F 136/06 (2006.01); C08F 136/08 (2006.01); C08K 3/04 (2006.01); C08K 3/36 (2006.01); C08L 7/00 (2006.01); C08L 9/06 (2006.01); C08L 15/00 (2006.01); C08L 57/02 (2006.01); C08L 91/00 (2006.01)
CPC B60C 1/0016 (2013.01) [C08F 136/06 (2013.01); C08F 136/08 (2013.01); C08K 3/04 (2013.01); C08K 3/36 (2013.01); C08L 7/00 (2013.01); C08L 9/06 (2013.01); C08L 15/00 (2013.01); C08L 57/02 (2013.01); C08L 91/00 (2013.01); C08K 2201/006 (2013.01); C08L 2205/035 (2013.01)] 22 Claims
 
1. A tire tread rubber composition comprising:
a. 100 parts of an elastomer component comprising
i. 30-45 parts of at least one styrene-butadiene rubber having a Tg of about −10 to about −20° C.,
ii. 30-45 parts of polybutadiene having a cis bond content of at least 95% and a Tg of less than −101° C., and
iii. 20-35 parts of natural rubber consisting of guayule natural rubber,
wherein the elastomer component includes less than 1 part of butyl rubber,
b. 100-150 phr of at least one reinforcing silica filler having a surface area of about 100 to about 400 m2/g and 1-20 phr of carbon black,
c. 23-40 phr of hydrocarbon resin consisting of at least one hydrocarbon resin having a Tg of about 70 to about 110° C., wherein the hydrocarbon resin includes 0 phr of terpene resin,
d. 10-30 phr of at least one oil,
e. a cure package,
wherein the tire tread rubber composition is free of phosphate ester plasticizer.