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 (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: The present invention provides: a cationic natural rubber latex comprising cationic natural rubber microparticles in which the surfaces of natural rubber microparticles are coated by a cationic polymer, a weight average molecular weight of the cationic polymer being from 3000 to 150000, a concentration of the cationic natural rubber being from 30 to 70% by mass, a viscosity at 20° C. being 500 mPa·s or less, and surface potential of the cationic natural rubber microparticles being ?3 mV or less; and a tire puncture sealant comprising the cationic natural rubber latex and an acidic resin emulsion, a mass ratio of a solid content of the cationic natural rubber latex to a solid content of the acidic resin emulsion being from 90:10 to 10:90. Such tire puncture sealant has superior puncture-sealing ability, storage stability, and workability.

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 coagulant with excellent coagulability performance, and a tire puncture repair kit that uses the coagulant. The present invention is a coagulant of a tire puncture repair liquid, the coagulant including at least one component selected from the group consisting of a plant protein, a pectin, a cellulose, a phospholipid and a fatty acid glyceride, and a tire puncture repair kit that uses the coagulant.

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: A tire puncture sealant according to the present technology is a tire puncture sealant containing a latex and/or an emulsion and an anti-freezing agent, the latex and/or emulsion containing, as solids, at least a polymer and/or an organic compound (other than the polymer), a content of solids being from 20 to 65% by mass with respect to the total mass of the sealant, and the difference between the specific gravity of the solids and the specific gravity of a mixture of water and anti-freezing agent in the tire puncture sealant being within ±0.1.

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 novel emulsion coagulant having excellent coagulability used in a tire puncture sealing agent, and a tire puncture repair kit that uses the same. The present invention is an emulsion coagulant comprising magnesium oxide and a silane coupling agent and a cellulose and/or magnesium hydroxide, wherein a mass ratio of the magnesium oxide to the silane coupling agent is from 100:0.5 to 100:15; and a tire puncture repair kit that uses the same.

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.

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 is a tire puncture repair kit including tire puncture repair liquid and a coagulant for a tire puncture repair liquid with excellent coagulability. The coagulant of the present invention coagulates a tire puncture repair liquid, and contains an ?-starch and/or a dextrin having a weight average molecular weight of 3,000 to 50,000.