Patent ID: 7001946
Filing Date: 2006-02-21
Classification: B60C,C08K,C08L

Abstract:
1. A tire having an outer circumferential tread of a natural rubber-rich, carbon black-rich, silica-containing sulfur cured rubber composition which comprises, based upon parts by weight per 100 parts by weight elastomer (phr): (A) diene-based elastomers as: (B) about 48 to about 76 phr of particulate reinforcing filler as rubber reinforcing carbon black and precipitated silica composed of about 25 to about 40 phr of said carbon black and wherein the weight ratio of said carbon black to said silica in a range of about 1.1/1 to 1.3/1, wherein: (C) a coupling agent having a moiety reactive with hydroxyl groups contained on the surface of said precipitated silica and another moiety interactive with said diene-based elastomers as a bis-(3-triethoxysilylpropyl) polysulfide having an average of from 2 to 2.6 or from 3.5 to 4 connecting sulfur atoms in its polysulfidic bridge; wherein said sulfur cured tire tread rubber composition has a balance of physical properties as: