Patent attributes
The present invention is directed to a pneumatic tire having a tread comprising a radially outer cap layer and radially inner cap layer underlying the outer cap layer; the outer cap layer comprising a vulcanizable rubber composition comprising, based on 100 parts by weight of elastomer (phr), from about 50 to about 90 phr of a solution polymerized styrene-butadiene rubber having a glass transition temperature (Tg) ranging from −65° C. to −55° C. and functionalized with an alkoxysilane group and at least one functional group selected from the group consisting of primary amines and thiols; from about 50 to about 10 phr of polybutadiene having a cis 1,4 content greater than 95 percent and a Tg ranging from −80 to −110° C.; from 30 to 80 phr of a combination of a resin having a Tg of at least 30° C. and an oil, wherein the weight ratio of resin to oil is greater than 1; and the inner cap layer comprising a vulcanizable rubber composition comprising: from about 50 to about 90 phr of a solution polymerized styrene-butadiene rubber functionalized with an alkoxysilane group and at least one functional group selected from the group consisting of primary amines and thiols; from about 50 to about 10 phr of polybutadiene having a cis 1,4 content greater than 95 percent and a Tg ranging from −80 to −110° C.; and from 30 to 50 phr of an oil, and essentially free of a resin.
