Abstract: A carbon black is disclosed which can exert excellent abrasion resistance while suppressing heat generation when incorporated into a rubber composition. A carbon black in which the total number of active sites represented by a product of a full width at half maximum of a Raman scattering peak appearing in a range of 1340 to 1360 cm?1 when an excitation wavelength is 532 nm and a specific surface area when nitrogen gas is adsorbed is 3.60×104 to 8.20×104 (cm?1·m2/g), and when a nuclear magnetic resonance signal of a spin-spin relaxation process observed by a solid echo method is represented by a sum of a first signal and a second signal having a time constant larger than that of the first signal, an amount of hydrogen represented by a signal intensity per unit mass at time 0 of the first signal is 50.0 to 250.0 (/g).

Abstract: It is intended to provide a carbon black which can confer reinforcing properties and low exothermicity, which are usually incompatible, as well as excellent abrasion resistance, when mixed with a rubber component, and is suitable for tire tread rubber that is used particularly under severe driving conditions. The present invention provides a carbon black having surface free energy ?d of 50 to 200 mJ/m2 determined by a reverse-phase gas chromatography analysis method and a strongly acidic group concentration of 0 to 0.115 ?mol/m2.

Abstract: It is intended to provide a carbon black which can confer reinforcing properties and low exothermicity, which are usually incompatible, as well as excellent abrasion resistance, when mixed with a rubber component, and is suitable for tire tread rubber that is used particularly under severe driving conditions. The present invention provides a carbon black having surface free energy ?d of 50 to 200 mJ/m2 determined by a reverse-phase gas chromatography analysis method and a strongly acidic group concentration of 0 to 0.115 ?mol/m2.

Abstract: A novel carbon black can improve rubber properties (e.g., degree of reinforcement and heat buildup). The carbon black has an aggregate void modal diameter Dmp determined by mercury porosimetry of 25 to 60 nm, and has a ratio (?Dmp/modal diameter Dmp) of a half-width ?Dmp of an aggregate void diameter distribution determined by mercury porosimetry to the aggregate void modal diameter Dmp of 0.30 to 0.56.