Manufacturing method of tire tread rubber composition and manufacturing method of tire in which rubber composition obtained by the method is arranged on tire tread

摘要

The present invention provides a method for producing a rubber composition for tire tread, which is prepared by mixing 100 parts by mass of a rubber component containing 60 to 80 parts by mass of a natural rubber and 20 to 40 parts by mass of a modified conjugated dienic polymer having one or more functional groups having another atom than carbon and hydrogen, and 40 to 60 parts by mass of carbon black having a nitrogen adsorption specific surface area (N 2 SA) of 40 to 95 m 2 /g and a hydrogen release rate of 0.37% by mass or more based on 100 parts by mass of the rubber component, wherein the temperature of the rubber composition at the time of discharge in the kneading step for mixing carbon black therein is 170°C or higher, a rubber composition obtained according to the production method, and a tire using the rubber composition. According to the production method for a rubber composition, the heat generation property of the rubber composition can be reduced, and the dynamic storage elastic modulus thereof can be increased. By using the rubber composition obtained according to the production method as tread, there can be provided a tire having not only reduced rolling resistance but also improved abrasion resistance, anti-tear performance (tear resistance) and cut resistance.