Abstract: An object of the present invention is to provide a rubber composition for a sidewall having excellent low heat build-up and durability when formed into a tire, and a pneumatic tire using the rubber composition. The rubber composition for a sidewall according to the present invention comprises a diene rubber and carbon black; the diene rubber comprising: a modified polymer obtained by reacting a nitrone compound with double bonds of a conjugated diene polymer; and a natural rubber; a content of the modified polymer in the diene rubber being from 8 to 65 mass %; a nitrogen adsorption specific surface area of the carbon black being from 20 to 60[×103 m2/kg]; and a content of the carbon black being from 30 to 67 parts by mass per 100 parts by mass of the diene rubber.

Abstract: The present invention is to provide a rubber composition for a tire tread, which can produce a studless tire having both excellent performance on ice and excellent wear resistance, and to provide a studless tire using the rubber composition. The rubber composition for a tire tread of the present invention contains 100 parts by mass of a diene rubber (A) containing a modified butadiene rubber and from 0.5 to 25 parts by mass of thermally expandable microcapsules (B). The modified butadiene rubber is obtained by modifying an unmodified butadiene rubber with a carboxy group-containing nitrone compound. The content of the modified butadiene rubber in the diene rubber (A) is from 20 to 65 mass %.

Abstract: An object of the present invention is to provide a rubber composition having excellent processability while excellent heat build-up reduction effect is maintained; and a pneumatic tire that uses the rubber composition. The rubber composition of the present invention contains: a diene rubber containing from 5 to 70 mass % of a modified butadiene rubber obtained by modifying an unmodified butadiene rubber (A) with a carboxy group-containing nitrone compound (B), the unmodified butadiene rubber (A) containing from 2 to 45 parts by mass of an unmodified low molecular weight butadiene rubber (A1) having from 1.5 to 60 mol % of vinyl bonding and having a number average molecular weight (Mn) of 2000 to 60000 per 100 parts by mass of an unmodified butadiene rubber (A2) having a number average molecular weight (Mn) greater than that of the unmodified low molecular weight butadiene rubber (A1).

Abstract: The present invention provides a rubber composition and a tire, which provides superior wear resistance and processability while maintaining the wet performance. The present invention provides a rubber composition for a tire including a rubber component including a modified diene rubber with carboxy group modification, silica and a predetermined polysiloxane; wherein the content of the silica is from 60 to 200 parts by mass per 100 parts by mass of the rubber component, the content of the polysiloxane is from 1 to 20 mass % based on the content of the silica, and the content of the modified diene rubber is from 10 to 100 parts by mass per 100 parts by mass of the rubber component. The present invention also provides a tire using the rubber composition.

Abstract: A rubber composition for coating a fiber cord includes a diene rubber, a carbon black, and a nitrone compound having a carboxy group; the diene rubber includes a natural rubber and a styrene-butadiene rubber and/or a butadiene rubber, wherein a content of the natural rubber in a total of the diene rubber and the nitrone compound is not greater than 65 mass %; a content of the carbon black is 40 to 67 parts by mass per 100 parts by mass of a total of the diene rubber and the nitrone compound; and a content of the nitrone compound is 0.1 to 10 parts by mass per 100 parts by mass of a total of the diene rubber and the nitrone compound. Such rubber composition for coating a fiber cord has excellent low heat build-up when a tire is produced and excellent adhesiveness with carcass cord.

Abstract: A rubber composition for a tire rim cushion or rubber finishing contains a diene rubber and a filler containing a carbon black. The diene rubber contains a natural rubber and/or an isoprene rubber, and a modified polymer that is obtained by reacting a nitrone compound with a double bond of a conjugated diene polymer. The content of the natural rubber and/or the isoprene rubber in the diene rubber is from 30 to 60 mass %, the content of the modified polymer in the diene rubber is from 8 to 70 mass %, the content of the filler is from 60 to 90 parts by mass per 100 parts by mass of the diene rubber, and the nitrogen adsorption specific surface area of the carbon black is from 60 to 150 m2/g. Such rubber composition has excellent low heat build-up and ozone resistance when formed into a tire.

Abstract: The present invention is to provide a compound that can provide a modified polymer exhibiting excellent rigidity, wear resistance, and low heat build-up when used in a rubber composition; a modified polymer obtained by subjecting a polymer to modification with the compound; a rubber composition including the modified polymer; and a tire and a conveyor belt that are produced by using the rubber composition. The compound of the present invention is represented by Formula (M) below.

Abstract: The present invention is to provide a compound that can provide a modified polymer exhibiting excellent rigidity, wear resistance, and low heat build-up when used in a rubber composition; a modified polymer obtained by subjecting a polymer to modification with the compound; a rubber composition including the modified polymer; and a tire and a conveyor belt that are produced by using the rubber composition. The compound of the present invention is represented by (M) below.

Abstract: An object of the present invention is to provide a rubber composition for a heavy-load tire having excellent low heat build-up when formed into a tire and excellent flowability of the rubber during vulcanization, and a pneumatic tire produced using the rubber composition. The rubber composition for a heavy-load tire contains a diene rubber and a carbon black; the diene rubber containing: a natural rubber; and a modified polymer obtained by modifying a conjugated diene polymer with a nitrone compound; the content of the natural rubber in the diene rubber being not less than 60 mass %; and the content of the modified polymer in the diene rubber being not greater than 40 mass %; and the content of the carbon black being from 30 to 70 parts by mass per 100 parts by mass of the diene rubber.

Abstract: The present invention provides a rubber composition for tire treads, the rubber composition achieving high rubber hardness and 300% modulus at high temperatures, and excellent dry grip properties when formed into a tire, along with a pneumatic tire obtainable by using the same. The rubber composition for tire treads of the present invention contains carbon black and a diene rubber including a carboxy-modified polymer. The carbon black content is from 80 to 150 parts by mass per 100 parts by mass of the diene rubber. The carboxy-modified polymer is obtained by modifying styrene-butadiene rubber (A) with a nitrone compound having carboxy group (B), and the content of the carboxy-modified polymer in the diene rubber is from 10 to 100 mass %. The content of styrene units in styrene-butadiene rubber (A) is at least 36 mass %. The degree of modification of the carboxy-modified polymer is from 0.02 to 4.0 mol %.

Abstract: An object of the present invention is to provide a rubber composition having excellent processability while excellent heat build-up reduction effect is maintained; and a pneumatic tire that uses the rubber composition. The rubber composition of the present invention contains: a diene rubber containing from 5 to 70 mass % of a modified butadiene rubber obtained by modifying an unmodified butadiene rubber (A) with a carboxy group-containing nitrone compound (B), the unmodified butadiene rubber (A) containing from 2 to 45 parts by mass of an unmodified low molecular weight butadiene rubber (A1) having from 1.5 to 60 mol % of vinyl bonding and having a number average molecular weight (Mn) of 2000 to 60000 per 100 parts by mass of an unmodified butadiene rubber (A2) having a number average molecular weight (Mn) greater than that of the unmodified low molecular weight butadiene rubber (A1).

Abstract: The present invention is to provide a rubber composition for a tire tread, which can produce a studless tire having both excellent performance on ice and excellent wear resistance, and to provide a studless tire using the rubber composition. The rubber composition for a tire tread of the present invention contains 100 parts by mass of a diene rubber (A) containing a modified butadiene rubber and from 0.5 to 25 parts by mass of thermally expandable microcapsules (B). The modified butadiene rubber is obtained by modifying an unmodified butadiene rubber with a carboxy group-containing nitrone compound. The content of the modified butadiene rubber in the diene rubber (A) is from 20 to 65 mass %.

Abstract: A rubber composition for tire treads contains an inorganic filler containing silica and a diene rubber containing a carboxy-modified polymer. The content of the inorganic filler is from 70 to 170 parts by mass per 100 parts by mass of the diene rubber. The content of the silica is from 70 to 160 parts by mass per 100 parts by mass of the diene rubber. The carboxy-modified polymer is obtained by modifying a styrene-butadiene rubber (A) with a nitrone compound (B) having a carboxy group, and the content of the carboxy-modified polymer in the diene rubber is from 10 to 100 mass %. The content of styrene units in the styrene-butadiene rubber (A) is not less than 36 mass %. The degree of modification of the carboxy-modified polymer is from 0.02 to 4.0 mol %.

Abstract: The present invention provides a rubber composition for an undertread, the rubber composition achieving excellent low heat build-up and high elastic modulus when formed into a tire; and a pneumatic tire that includes the rubber composition. The rubber composition for an undertread contains a diene rubber and a carbon black. The diene rubber contains a natural rubber and a modified polymer that is obtained by reacting a nitrone compound with a double bond of a conjugated diene polymer. The content of the natural rubber in the diene rubber is 60 mass % or greater, the content of the modified polymer in the diene rubber is from 8 to 40 mass %, the content of the carbon black is from 30 to 67 parts by mass per 100 parts by mass of the diene rubber, and the nitrogen adsorption specific surface area of the carbon black is from 20 to 60 m2/g.

Abstract: The present invention is to provide: a rubber composition which has excellent wet grip performance and wear resistance while maintaining the elongation thereof at a high level; and a pneumatic tire and a conveyer belt produced using the rubber composition. The present invention provides: a rubber composition containing a polymer containing from 10 to 90 mass % of a modified diene rubber having a carboxy group and an epoxy compound having a plurality of epoxy groups in each molecule, the content of the epoxy compound being from 0.1 to 5 parts by mass per 100 parts by mass of the polymer; and a pneumatic tire and a conveyor belt produced using the rubber composition.

Abstract: The present invention is to provide: a rubber composition which has excellent wet grip performance and also has excellent wear resistance while maintaining high elongation; and a pneumatic tire and a conveyer belt each of which is manufactured using the rubber composition. The present invention provides: a rubber composition containing a modified diene rubber, in the modified rubber, from 0.02 to 4 mol % of double bonds contained in a diene rubber being modified into hydroxy groups by reacting at least one type of diene rubber selected from the group consisting of styrene butadiene rubbers, butadiene rubbers, and nitrile butadiene rubbers with a hydroxy group-containing nitrone compound having both a hydroxy group and a nitrone group; and a pneumatic tire and a conveyer belt each of which is manufactured using the rubber composition.

Abstract: The purpose of the present invention is to provide a modified polymer that significantly reduces heat build-up due to the modification when the modified polymer is formed into a rubber composition, a rubber composition containing the modified polymer, and a pneumatic tire in which the rubber composition is used. The modified polymer of the present invention is a modified polymer obtained by modifying a styrene-conjugated diene copolymer (A) with a nitrone compound (B). In the modified polymer, the content of styrene units in the styrene-conjugated diene copolymer (A) is 10% by mass or greater, and the proportion of vinyl bonds among all the double bonds contained in the styrene-conjugated diene copolymer (A) is 5 mol % or greater.

Abstract: An object of the present invention is to provide a rubber composition capable of producing a pneumatic tire with both excellent low rolling resistance and wet grip performance, and a pneumatic tire comprising the rubber composition. The rubber composition comprises: a diene-based rubber containing 10 mass % or greater of a modified diene polymer; and an aromatic modified terpene resin; wherein the modified diene polymer is a modified polymer obtained by modifying an unmodified diene polymer (A) with a nitrone compound (B) having a carboxy group; and a content of the aromatic modified terpene resin is from 0.1 to 50 parts by mass per 100 parts by mass of the diene-based rubber.

Abstract: An object of the present invention is to provide a rubber composition capable of producing a pneumatic tire with both satisfactory heat build-up reduction and excellent wet skid performance, and a pneumatic tire comprising the rubber composition. The rubber composition of the present invention contains a diene-based rubber containing from 5 to 40 mass % of a modified butadiene rubber and a white filler. The modified butadiene rubber is a modified polymer obtained by modifying an unmodified butadiene rubber (A) with a nitrone compound (B) having a carboxy group.

Abstract: An object of the present invention is to provide a modified polymer that can realize a rubber composition having excellent low heat build-up and that has excellent productivity, a rubber composition containing the modified polymer, and a tire produced using the rubber composition. The modified polymer of the present invention is obtained by reacting a modifier having a nitrone group and a carboxy group with a conjugated diene polymer not containing a tetrasubstituted olefin and/or a trisubstituted olefin.