Provided are a rubber composition containing from 1 to 30 parts by mass of an acid-modified polyolefin and from 0.3 to 20 parts by mass of at least one type selected from the group consisting of terpene resins and petroleum resins per 100 parts by mass of a diene rubber; and a pneumatic tire using the same.

The invention relates to rubber comprised of a reaction product of at least one diene-based elastomer, branched polyethylenimine oligomer and filler reinforcement comprised of at least one of rubber reinforcing carbon black and precipitated silica. The invention further relates to a tire with a component comprised of such rubber composition.

In a tire, a tread includes a cap layer forming a part of the outer surface of the tire, an intermediate layer disposed inwardly of the cap layer in the radial direction, and a base layer disposed inwardly of the intermediate layer in the radial direction. A loss tangent of the intermediate layer at 30° C. is less than a loss tangent of the cap layer at 30° C., and a loss tangent of the base layer at 30° C. is less than the loss tangent of the intermediate layer at 30° C. An outer end of the cap layer is disposed outwardly of an outer end of the base layer in the axial direction. In the radial direction, a position of the outer end of the cap layer coincides with a position of the outer end of the base layer, or the outer end of the cap layer is disposed inwardly of the outer end of the base layer.

A racing tire comprising a tread having a new tread thickness of no greater than about 0.375 inch. The tread defines a running surface that includes a first circumferential portion of a first rubber compound and a second circumferential portion of a second rubber compound situated adjacent one another. The first rubber compound has a greater stiffness than the second rubber compound so as to provide the tread with greater wear resistance along the first circumferential portion, and the second rubber compound provides the tread with greater traction along the second circumferential portion. The tread may be substantially free of a tread pattern. The second rubber compound may have a greater DIN abrasion value than the first rubber compound. The second rubber compound may have a higher tan delta at 100° C. and/or a higher J″ traction value than the first rubber compound.

A tread made of rubber-like material for a tire for winter travel having a plurality of blocks of a height H, each block comprising a contact face designed to come into contact with the ground when the tire travels and at least one lateral face, said lateral face being covered by a layer of covering material over at least 50% of the surface thereof, and a leading zone designed to come into contact first with the ground when the tire travels, and said block has an oblique direction of extension (J) such that the leading zone of said block is a leading corner, and a part which is not covered by the covering material, said covering material having a modulus of elasticity which is greater than the modulus of elasticity of the rubber-like material forming the block, said uncovered part extending from the leading corner over at least ⅓ of the height H of the block.

Provided is a rubber composition for tires having low tan δ at approximately 60° C. and excellent fracture energy at approximately 25° C. Included is a rubber composition for tires, containing a rubber component including an isoprene-based rubber, the rubber composition having a correlation length Ξ.sub.b of 55 nm or less as determined by fitting the following Equations 1 to 6 to a scattering intensity curve I(q) obtained by X-ray scattering analysis or neutron scattering analysis: $\begin{array}{cc}{I}_{\left(q\right)}=\frac{A}{1+q^2{\xi }^2}+\frac{B}{{\left(1+q^2{\Xi }_b^2\right)}^2}+\frac{C}{{\left(1+q^2{\Xi }_c^2\right)}^2}& (\mathrm{Equation}\end{array}$

Tire having improved wet grip performance and improved resistance to breaking or chipping along with good fuel economy. The tire includes a tire component (preferably, a tire tread) formed of a vulcanized rubber composition. The vulcanized rubber composition is obtained by vulcanizing a specific unvulcanized rubber composition. The unvulcanized rubber composition comprises (a) a rubber component composed of natural rubber, polybutadiene rubber, and two different types of styrene-butadiene rubber, (b) a filler that includes silica, and (c) a silane coupling agent that incorporates a —C(═O)—S— moiety.

This invention relates to a tire with a tread of a rubber composition that promotes a combination of winter traction at low temperatures and for promoting wet traction. The tread rubber composition contains a combination of low surface area silica and high softening point traction resin. Elastomers for the tread rubber composition are comprised of high cis 1,4-polybutadiene rubber and styrene/butadiene rubber.

Provided are a tread rubber composition which provides a balanced improvement in wet grip performance and resistance to low-temperature brittleness, and a pneumatic tire including a tread at least partially containing the rubber composition. The present invention relates to a tread rubber composition containing a styrene-butadiene rubber and having a tan δ peak temperature of −10° C. or higher and a brittleness temperature of −40° C. or lower.

The present invention relates to a tire tread comprising a tread cap comprising at least one tread cap rubber compound, at least three circumferential grooves, wherein at least portions of the sidewalls and the bottom of each of said grooves are formed by a circumferential groove reinforcement, and wherein a first groove reinforcement of a groove laterally next to the equatorial plane of the tire comprises a first reinforcement rubber compound which has a higher hardness than the tread cap rubber compound, and wherein a second groove reinforcement of a groove with a larger lateral distance to the equatorial plane of the tire than the first groove, comprises a second reinforcement rubber compound which has a higher hardness than the tread cap rubber compound and a lower hardness than the second reinforcement rubber compound.