Abstract: The present invention is to provide an aromatic vinyl-diene copolymer which exhibits excellent mechanical properties and wear resistance when being formed into a tire, a method for producing the aromatic vinyl-diene copolymer, and a rubber composition containing the aromatic vinyl-diene copolymer. The aromatic vinyl-diene copolymer of an embodiment of the present invention is an aromatic vinyl-diene copolymer which is a copolymer of an aromatic vinyl and a diene, wherein the content of a repeating unit derived from an aromatic vinyl is 18 mass % or greater, among repeating units derived from a diene, a proportion of a vinyl structure is 8 mol % or less, a proportion of a 1,4-trans structure is 75 mol % or less, and a proportion of a 1,4-cis structure is from 17 to 90 mol %, and a glass transition temperature is ?60° C. or lower.

Abstract: The present invention is to provide a diene polymer that exhibits excellent low rolling resistance when used in a tire, a method for producing the diene polymer, and a rubber composition containing the diene polymer. The diene polymer of an embodiment of the present invention is produced by polymerizing a monomer containing at least a diene monomer by using an initiator prepared from an organolithium compound, an alkyl aluminum, and a metal alcoholate, and then terminating the polymerization by using an electrophile selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by Formula (N) below.

Abstract: A rubber composition for a tire contains: 100 parts by mass of a diene rubber (A); from 30 to 100 parts by mass of a filler (B); from 0.3 to 30 parts by mass of a crosslinkable component (C) that is not miscible with the diene rubber (A); and a fibrillated fiber (D). The fibrillated fiber (D) is dispersed in advance in the crosslinkable component (C) in a proportion of 0.1 to 10 mass % of the crosslinkable component (C), and the crosslinkable component (C) is a polyether-based, polyester-based, polyolefin-based, polycarbonate-based, aliphatic-based, saturated hydrocarbon-based, acrylic-based, or plant-derived polymer or copolymer.

Abstract: A pneumatic tire using as a tread part, a rubber composition containing a high silica-content rubber composition having a difference F-S between an amount of filler F and an amount of a softening agent S of 60 to 90 parts by weight and having a durometer hardness measured at 20° C. of 65 to 76.

Abstract: The present invention is to provide an aromatic vinyl-diene copolymer which exhibits excellent mechanical properties and wear resistance when being formed into a tire, a method for producing the aromatic vinyl-diene copolymer, and a rubber composition containing the aromatic vinyl-diene copolymer. The aromatic vinyl-diene copolymer of an embodiment of the present invention is an aromatic vinyl-diene copolymer which is a copolymer of an aromatic vinyl and a diene, wherein the content of a repeating unit derived from an aromatic vinyl is 18 mass % or greater, among repeating units derived from a diene, a proportion of a vinyl structure is 8 mol % or less, a proportion of a 1,4-trans structure is 75 mol % or less, and a proportion of a 1,4-cis structure is from 17 to 90 mol %, and a glass transition temperature is ?60° C. or lower.

Abstract: The present invention is to provide a diene polymer that exhibits excellent low rolling resistance when used in a tire, a method for producing the diene polymer, and a rubber composition containing the diene polymer. The diene polymer of an embodiment of the present invention is produced by polymerizing a monomer containing at least a diene monomer by using an initiator prepared from an organolithium compound, an alkyl aluminum, and a metal alcoholate, and then terminating the polymerization by using an electrophile selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by Formula (N) below.

Abstract: A rubber composition for a tire contains: 100 parts by mass of a diene rubber (A); from 30 to 100 parts by mass of a filler (B); from 0.3 to 30 parts by mass of a crosslinkable component (C) that is not miscible with the diene rubber (A); and a fibrillated fiber (D). The fibrillated fiber (D) is dispersed in advance in the crosslinkable component (C) in a proportion of 0.1 to 10 mass % of the crosslinkable component (C), and the crosslinkable component (C) is a polyether-based, polyester-based, polyolefin-based, polycarbonate-based, aliphatic-based, saturated hydrocarbon-based, acrylic-based, or plant-derived polymer or copolymer.

Abstract: A rubber composition for a tire tread comprising (A) 100 parts by weight of a rubber component containing (a) 50 to 95 parts by weight of a diene-based rubber containing 50 to 100% by weight of an aromatic vinyl-conjugated diene copolymer rubber and (b) 5 to 50 parts by weight of a conjugated diene-based rubber gel having a toluene swelling index Qi of 16 to 70 and (B) 3 to 40 parts by weight, based upon 100 parts by weight of the total rubber component, of a copolymer resin of an aromatic vinyl and dipentene and/or pinene having a softening point of 100 to 150° C. and a high performance tire using the above rubber composition are disclosed.

Abstract: A rubber composition containing (i) a conjugated diene-based rubber gel having a toluene swelling index of 16 to 70, (ii) a diene-based rubber such as natural rubber, polyisoprene rubber, aromatic vinyl-conjugated diene copolymer rubber and/or polybutadiene rubber, and (iii) an optional carbon black and/or silica and (a) a pneumatic tire using this composition as a high hardness reinforcing layer extending from a bead along a tire sidewalls, in which the fluidity and dimensional stability at the time of extrusion are improved, while maintaining a sufficient hardness of a high hardness reinforced rubber, (b) a pneumatic tire using this composition as two ends of a tire tread extrudate, maintaining a flex fatigue of the two ends of the tread, in which the extrudability and extrusion dimensional stability are improved and (c) a pneumatic tire using the composition as a 1.

Abstract: Provided is a tire rubber composition blended with an antioxidant that is derived from a raw material other than petroleum resources, the tire rubber composition being capable of achieving an oxidation resistance equal to or higher than a conventional level and of improving forming processability and a low hysteresis loss property. The tire rubber composition includes a blend of: 100 parts by weight of a diene rubber; 5 to 130 parts by weight of an inorganic filler; and 0.01 to 10 parts by weight of a tea extract containing a catechin.

Abstract: A rubber composition for a pneumatic tire containing 100 parts by weight of a diene-based rubber and 5 to 120 parts by weight of carbon black having a particle size of 15 to 40 nm, a nitrogen absorption specific surface area N2SA of 60 to 200 m2/g, and a pH of 1 to 5 or 8.5 to 13, which can improve wet performance of a tire without causing problems in productivity and conductivity.

Abstract: A rubber composition for a pneumatic tire containing 100 parts by weight of a diene-based rubber and 5 to 120 parts by weight of carbon black having a particle size of 15 to 40 nm, a nitrogen absorption specific surface area N2SA of 60 to 200 m2/g, and a pH of 1 to 5 or 8.5 to 13, which can improve wet performance of a tire without causing problems in productivity and conductivity.

Abstract: A rubber composition for a tire tread including 100 parts by weight of a diene-based rubber and 5 to 150 parts by weight of carbon black having a nitrogen adsorption specific area N2SA (m2/g) of 80 to 150 and satisfying a relationship between a TINT (%) and dibutyl phthalate absorption DBPA (ml/100 g) of TINT (%)>1.4 DBPA (ml/100 g) and capable of increasing the frictional force without impairing the hysteresis loss.

Abstract: Provided is a tire rubber composition blended with an antioxidant that is derived from a raw material other than petroleum resources, the tire rubber composition being capable of achieving an oxidation resistance equal to or higher than a conventional level and of improving forming processability and a low hysteresis loss property. The tire rubber composition includes a blend of: 100 parts by weight of a diene rubber; 5 to 130 parts by weight of an inorganic filler; and 0.01 to 10 parts by weight of a tea extract containing a catechin.

Abstract: A rubber composition containing 100 parts by weight a sulfur-vulcanizable rubber (A) and 0.1 to 30 parts by weight of a vulcanization agent of a cyclic polysulfide (B) having the formula (I): wherein R is a substituted or unsubstituted C2 to C20 alkylene group, substituted or unsubstituted C2 to C20 oxyalkylene group or alkylene group having an aromatic ring, n is an integer of 1 to 20, x is a number of 2 to 6 on average.

Abstract: A pneumatic tire allowed to increase steering stability and durability while reducing rolling resistance, wherein a reinforced rubber layer extending from a bead part along a side wall part is installed in the side wall part. A rubber composition forming the reinforced rubber layer has a loss of tangent (tan ?) measured at 60° C. of 0.01 to 0.25, a JIS-A hardness measured at 23° C. of 70 to 95, and a breaking elongation in a tension test measured at 23° C. of 200% or more.

Abstract: A rubber composition for a pneumatic tire containing 100 parts by weight of a diene-based rubber and 5 to 120 parts by weight of carbon black having a particle size of 15 to 40 nm, a nitrogen absorption specific surface area N2SA of 60 to 200 m2/g, and a pH of 1 to 5 or 8.5 to 13, which can improve wet performance of a tire without causing problems in productivity and conductivity.

Abstract: A pneumatic tire using as a tread part, a rubber composition containing a high silica-content rubber composition having a difference F-S between an amount of filler F and an amount of a softening agent S of 60 to 90 parts by weight and having a durometer hardness measured at 20° C. of 65 to 76.

Abstract: A rubber composition for a tire tread comprising (A) 100 parts by weight of a rubber component containing (a) 50 to 95 parts by weight of a diene-based rubber containing 50 to 100% by weight of an aromatic vinyl-conjugated diene copolymer rubber and (b) 5 to 50 parts by weight of a conjugated diene-based rubber gel having a toluene swelling index Qi of 16 to 70 and (B) 3 to 40 parts by weight, based upon 100 parts by weight of the total rubber component, of a copolymer resin of an aromatic vinyl and dipentene and/or pinene having a softening point of 100 to 150° C. and a high performance tire using the above rubber composition are disclosed.

Abstract: A rubber composition for a pneumatic tire containing 100 parts by weight of a diene-based rubber and 5 to 120 parts by weight of carbon black having a particle size of 15 to 40 nm, a nitrogen absorption specific surface area N2SA of 60 to 200 m2/g, and a pH of 1 to 5 or 8.5 to 13, which can improve wet performance of a tire without causing problems in productivity and conductivity.