| abstract |
A tyre tread rubber composition comprises (a) about 60 phr to about 90 phr of a high cis-l,4-polybutadiene rubber, wherein the high cis-1,4-polybutadiene rubber has a glass transition temperature which is within the range of about -104{C to about -80{C, (b) about 10 phr to about 40 phr of at least one additional rubbery polymer selected from the group consisting of polyisoprene rubber, polybutadiene rubber and styrene-isoprene-butadiene rubber, wherein the additional rubbery polymer has a glass transition temperature which is within the range of about -30{C to about -10{C isoprene-butadiene rubber, (c) about 20 phr to about 60 phr of carbon black, wherein the carbon black has a DBP absorption value of at least 140 cm<SP>3</SP>/100 grams and wherein the carbon black has a CTAB adsorption area which is within the range of about 60 to about 90. |