Abstract: Provided is a pneumatic tire which prevents accumulation of static electricity during travelling, which inhibits the tire from rising in an electric resistance with the passage of time, and which is reduced in a rolling resistance of the tire and excellent in durability thereof. In the pneumatic tire described above, a conductive rubber is arranged for a ply coating rubber of one surface, and a non-conductive rubber is arranged for the ply coating rubber of the other surface; assuming that the respective thicknesses thereof are T1 and T2, a carcass ply has a ply in which T1/T2 satisfies 0.2?T1/T2?0.9; and the conductive ply coating rubber is arranged at a tread side, and the non-conductive ply coating rubber is arranged at an inner liner side.

Abstract: Provided is a pneumatic tire in which an electric resistance can be reduced without adversely affecting other performances such as tire durability or manufacturing processes even when low loss of a rubber member of the tire is attempted. The pneumatic tire includes a belt layer 2 provided at an outer side of a crown portion of a carcass 1 in a tire radial direction, and a rubber chafer 4 is provided at an outer surface of a bead portion in a tire width direction.

Abstract: An object of the present invention is to provide a rubber composition for a tire, capable of achieving both good rolling resistance properties and good wear resistance in a sufficiently compatible manner when the rubber composition is applied to a component member of a tire. Specifically, the present invention provides a rubber composition comprising a rubber composition and hydrated silica, wherein “CTAB” (m2/g) as specific surface area by cetyltrimethylammonium bromide adsorption and “IB” as ink bottle-shaped micropore index, of the hydrated silica, satisfy a specific relationship and “weight loss on ignition” as weight loss when the hydrate silicate is heated at 750° C. for 3 hours and “weight loss on heating” as weight loss when the hydrate silicate is heated at 105° C. for 2 hours satisfy a specific relationship.

Abstract: Provided are a rubber composition using an antioxidant synthesized from biological resources including botanical resources, wherein the value of ?13C of the antioxidant is from ?30‰ to ?26‰, or ?22‰ or more, and a tire using the rubber composition.

Abstract: An object of the present invention is to provide a rubber composition capable of achieving both good rolling resistance properties and good wear resistance in a compatible manner when the rubber composition is applied to a component member, e.g. tread, of a tire. Specifically, the present invention provides a rubber composition comprising a rubber composition and hydrated silica, wherein “CTAB” (m2/g) as specific surface area by cetyltrimethylammonium bromide adsorption and “IB” as ink bottle-shaped micropore index, of the hydrated silica, satisfy a specific relationship and “weight loss on ignition” (mass %) as weight loss when the hydrate silicate is heated at 750 ° C. for 3 hours and “weight loss on heating” (mass %) as weight loss when the hydrate silicate is heated at 105 ° C. for 2 hours satisfy a specific relationship.

Abstract: The present invention provides carbon black, the standard deviation ? of aggregate size distribution of which is obtained by alight scattering method using an ultraviolet ray, the standard deviation ? satisfying the expression (1): ?<?48.7×(24M4DBP/Dst)+161.8 (1). In the expression (1), 24M4DBP represents the dibutyl phthalate absorption number (cm3/100 g) of compressed sample, and Dst (nm) is a Stokes' equivalent diameter providing the mode in aggregate size distribution obtained by a centrifugal sedimentation method. The carbon black can improve both the abrasion resistance and the low rolling resistance of a tire. The present invention also provides a rubber composition mixed with this carbon black, and a pneumatic tire including a tread part formed by using this rubber composition.

Abstract: An object of the present invention is to provide: a rubber composition which, when it is applied to a component member (such as a tread) of a tire, exhibits good wear resistance without deteriorating rolling resistance of the tire; a cross-linked rubber composition obtained by cross-linking the rubber composition; and a tire using the rubber composition or the cross-linked rubber composition as a material thereof. Specifically, the present invention provides a rubber composition obtained by blending and kneading a rubber component and hydrated silica together, characterized in that: provided that D represents the average primary particle diameter and LP represents the log differential pore volume at a pore diameter of 30 nm, of the hydrated silica in the rubber composition, D and LP satisfy relationships represented by following formula (1) and (2). LP>?0.045×D+1.45??(1) D<30 nm??(2).

Abstract: An object of the present invention is to provide a rubber composition for a tire, capable of achieving both good rolling resistance properties and good wear resistance in a sufficiently compatible manner when the rubber composition is applied to a component member of a tire. Specifically, the present invention provides a rubber composition comprising a rubber composition and hydrated silica, wherein “CTAB” (m2/g) as specific surface area by cetyltrimethylammonium bromide adsorption and “IB” as ink bottle-shaped micropore index, of the hydrated silica, satisfy a specific relationship and “weight loss on ignition” as weight loss when the hydrate silicate is heated at 750° C. for 3 hours and “weight loss on heating” as weight loss when the hydrate silicate is heated at 105° C. for 2 hours satisfy a specific relationship.

Abstract: The present invention provides carbon black, the standard deviation ? of aggregate size distribution of which is obtained by alight scattering method using an ultraviolet ray, the standard deviation ? satisfying the expression (1): ?<?48.7×(24M4DBP/Dst)+161.8 (1). In the expression (1), 24M4DBP represents the dibutyl phthalate absorption number (cm3/100 g) of compressed sample, and Dst (nm) is a Stokes' equivalent diameter providing the mode in aggregate size distribution obtained by a centrifugal sedimentation method. The carbon black can improve both the abrasion resistance and the low rolling resistance of a tire. The present invention also provides a rubber composition mixed with this carbon black, and a pneumatic tire including a tread part formed by using this rubber composition.

Abstract: An object of the present invention is to provide: a rubber composition which, when it is applied to a component member (such as a tread) of a tire, exhibits good wear resistance without deteriorating rolling resistance of the tire; a cross-linked rubber composition obtained by cross-linking the rubber composition; and a tire using the rubber composition or the cross-linked rubber composition as a material thereof. Specifically, the present invention provides a rubber composition obtained by blending and kneading a rubber component and hydrated silica together, characterized in that: provided that D represents the average primary particle diameter and LP represents the log differential pore volume at a pore diameter of 30 nm, of the hydrated silica in the rubber composition, D and LP satisfy relationships represented by following formulae (1) and (2). LP>?0.045×D+1.

Abstract: An object of the present invention is to provide a rubber composition capable of achieving both good rolling resistance properties and good wear resistance in a compatible manner when the rubber composition is applied to a component member, e.g. tread, of a tire. Specifically, the present invention provides a rubber composition comprising a rubber composition and hydrated silica, wherein “CTAB” (m2/g) as specific surface area by cetyltrimethylammonium bromide adsorption and “IB” as ink bottle-shaped micropore index, of the hydrated silica, satisfy a specific relationship and “weight loss on ignition” (mass %) as weight loss when the hydrate silicate is heated at 750 ° C. for 3 hours and “weight loss on heating” (mass %) as weight loss when the hydrate silicate is heated at 105 ° C. for 2 hours satisfy a specific relationship.

Abstract: The invention relates to a rubber composition for a tire tread simultaneously establishing a high wear resistance and a low heat buildup, and more particularly to a rubber composition for a tire tread comprising 10-250 parts by weight of a carbon black per 100 parts by weight of a rubber component, in which said carbon black is produced in a carbon black production step satisfying the following relational equations (1) and (2): 2.00???9.00??(1) ?2.5x?+85.0???90.0??(2) when a residence time from the introduction of the starting hydrocarbon into the high-temperature combustion gas flow to the introduction of the quenching medium is t1 (sec), an average reaction temperature for such a time is T1 (° C.), a residence time from the introduction of the quenching medium to the enter of a reaction gas flow into the reaction stop zone is t2 (sec), an average reaction temperature for such a time is T2 (° C.), ?=t1×T1 and ?=t2×T2.

Abstract: The invention relates to a rubber composition for a tire tread simultaneously establishing a high wear resistance and a low heat buildup, and more particularly to a rubber composition for a tire tread comprising 10-250 parts by weight of a carbon black per 100 parts by weight of a rubber component, in which said carbon black is produced in a carbon black production step satisfying the following relational equations (1) and (2): 2.00???9.00??(1) ?2.5×?+85.0???90.0??(2) when a residence time from the introduction of the starting hydrocarbon into the high-temperature combustion gas flow to the introduction of the quenching medium is t1 (sec), an average reaction temperature for such a time is T1 (° C.), a residence time from the introduction of the quenching medium to the enter of a reaction gas flow into the reaction stop zone is t2 (sec), an average reaction temperature for such a time is T2 (° C.), ?=t1×T1 and ?=t2×T2.