Abstract: A rubber composition comprises a diene rubber including not less than 30% by weight of a modified conjugated diene polymer rubber and, per 100 parts by weight of the diene rubber, from 1 to 25 parts by weight of a tackifying resin, and from 25 to 80 parts by weight of a filler comprising not less than 50% by weight of silica. The modified conjugated diene polymer rubber has a terminal modified group comprising a functional group that interacts with silica. In the modified conjugated diene polymer rubber, aromatic vinyl unit content is from 38% to 48% by weight, vinyl unit content is from 20% to 35%, weight-average molecular weight is from 600,000 to 1,000,000, and glass transition temperature is from ?22 to ?32° C. A glass transition temperature of the tackifying resin is from 50 to 110° C. higher than the glass transition temperature of the modified conjugated diene polymer rubber.

Abstract: A rubber composition for use in tire treads comprising from 60 to 130 parts by weight of silica per 100 parts by weight of diene rubber containing not less than 50% by weight of hydroxyl group-containing modified styrene butadiene rubber, in which the weight ratio of oil to filler containing the silica is not greater than 0.25, and a silane coupling agent having a mercapto group and an Si—O bond is compounded in an amount from 4 to 15% by weight of the silica content, and diethylene glycol is compounded in an amount from 1 to 6% by weight of the silica content.

Abstract: A rubber composition for use in tire treads comprises a diene rubber including not less than 40% by weight of a modified conjugated diene polymer rubber and, per 100 parts by weight of the diene rubber, from 66 to 110 parts by weight of a filler. The filler comprises not less than 50% by weight of silica. The modified conjugated diene polymer rubber is obtained by copolymerizing a conjugated diene monomer unit and an aromatic vinyl monomer unit in a hydrocarbon solvent using an organic active metal compound as an initiator. A resulting active conjugated diene polymer chain thereof has a terminal modified group, obtained by reacting at least one type of compound having a functional group that is reactable with the active terminal of the polymer chain. Moreover, the terminal modified group has a functional group that interacts with the silica.

Abstract: A rubber composition comprises a diene rubber including not less than 25% by weight of a modified conjugated diene polymer rubber and, per 100 parts by weight of the diene rubber, from 25 to 65 parts by weight of a filler, the filler comprising not less than 50% by weight of silica. The silica has a DBP absorption number of 190 to 250 ml/100 g, an N2SA of 194 to 225 m/g, and a CTAB of 185 to 215 m2/g. A ratio of the N2SA to the CTAB is from 0.9 to 1.4. The modified conjugated diene polymer rubber has a terminal modified group including a functional group that interacts with the silica. In the modified conjugated diene polymer rubber, aromatic vinyl unit content is from 38% to 48% by weight, vinyl unit content is from 20% to 35%, and weight-average molecular weight is from 600,000 to 1,000,000.

Abstract: A rubber composition for use in tire treads comprising from 60 to 130 parts by weight of silica per 100 parts by weight of diene rubber containing not less than 50% by weight of hydroxyl group-containing modified styrene butadiene rubber, in which the weight ratio of oil to filler containing the silica is not greater than 0.25, and a silane coupling agent having a mercapto group and an Si—O bond is compounded in an amount from 4 to 15% by weight of the silica content, and diethylene glycol is compounded in an amount from 1 to 6% by weight of the silica content.

Abstract: A rubber composition for use in tire treads comprises a diene rubber including not less than 40% by weight of a modified conjugated diene polymer rubber and, per 100 parts by weight of the diene rubber, from 66 to 110 parts by weight of a filler. The filler comprises not less than 50% by weight of silica. The modified conjugated diene polymer rubber is obtained by copolymerizing a conjugated diene monomer unit and an aromatic vinyl monomer unit in a hydrocarbon solvent using an organic active metal compound as an initiator. A resulting active conjugated diene polymer chain thereof has a terminal modified group, obtained by reacting at least one type of compound having a functional group that is reactable with the active terminal of the polymer chain. Moreover, the terminal modified group has a functional group that interacts with the silica.

Abstract: A rubber composition comprises a diene rubber including not less than 25% by weight of a modified conjugated diene polymer rubber and, per 100 parts by weight of the diene rubber, from 25 to 65 parts by weight of a filler, the filler comprising not less than 50% by weight of silica. The silica has a DBP absorption number of 190 to 250 ml/100 g, an N2SA of 194 to 225 m/g, and a CTAB of 185 to 215 m2/g. A ratio of the N2SA to the CTAB is from 0.9 to 1.4. The modified conjugated diene polymer rubber has a terminal modified group including a functional group that interacts with the silica. In the modified conjugated diene polymer rubber, aromatic vinyl unit content is from 38% to 48% by weight, vinyl unit content is from 20% to 35%, and weight-average molecular weight is from 600,000 to 1,000,000.

Abstract: A rubber composition comprises a diene rubber including not less than 30% by weight of a modified conjugated diene polymer rubber and, per 100 parts by weight of the diene rubber, from 1 to 25 parts by weight of a tackifying resin, and from 25 to 80 parts by weight of a filler comprising not less than 50% by weight of silica. The modified conjugated diene polymer rubber has a terminal modified group comprising a functional group that interacts with silica. In the modified conjugated diene polymer rubber, aromatic vinyl unit content is from 38% to 48% by weight, vinyl unit content is from 20% to 35%, weight-average molecular weight is from 600,000 to 1,000,000, and glass transition temperature is from ?22 to ?32° C. A glass transition temperature of the tackifying resin is from 50 to 110° C. higher than the glass transition temperature of the modified conjugated diene polymer rubber.