Abstract: A rubber composition according to an embodiment includes: a rubber component comprising diene rubber; and fine particles which are formed of a specific polymer and have a glass transition point of ?70° C. to 0° C. The fine particles are fine particles formed of a (meth)acrylate polymer having a constitutional unit represented by formula (1) or formed of a polymer having a constitutional unit represented by formula (4). In formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 4 to 18 carbon atoms. In formula (4), at least one of R11, R12, R13, R14, R15, and R16 represents an aliphatic hydrocarbon group having 3 to 8 carbon atoms, and the remainder represents a hydrogen atom or an aliphatic hydrocarbon group having 1 or 2 carbon atoms.

Abstract: A rubber composition, comprises a rubber component; and a completely amorphous olefin based elastomer having a glass transition temperature Ig of ?40 to 20° C. in an amount of 1 to 40 parts by mass when the entire amount of the rubber component is regarded as 100 parts by mass. It is preferred that the rubber composition further comprises a liquid rubber in an amount of 1 to 40 parts by mass.

Abstract: A rubber composition, comprises a rubber component; and a completely amorphous olefin based elastomer having a glass transition temperature Ig of ?40 to 20° C. in an amount of 1 to 40 parts by mass when the entire amount of the rubber component is regarded as 100 parts by mass. It is preferred that the rubber composition further comprises a liquid rubber in an amount of 1 to 40 parts by mass.

Abstract: A rubber composition according to an embodiment includes: a rubber component comprising diene rubber; and fine particles which are formed of a specific polymer and have a glass transition point of ?70° C. to 0° C. The fine particles are fine particles formed of a (meth)acrylate polymer having a constitutional unit represented by formula (1) or formed of a polymer having a constitutional unit represented by formula (4). In formula (1), R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group having 4 to 18 carbon atoms. In formula (4), at least one of R11, R12, R13, R14, R15, and R16 represents an aliphatic hydrocarbon group having 3 to 8 carbon atoms, and the remainder represents a hydrogen atom or an aliphatic hydrocarbon group having 1 or 2 carbon atoms.

Abstract: A rubber composition, comprising solution-polymerized polystyrene butadiene rubber in an amount of 10 to 80 parts by mass when the entire amount of rubber components in the composition is regarded as 100 parts by mass; and a thermoplastic elastomer in an amount of 1 to 20 parts by mass for the 100 parts by mass of the rubber components; the thermoplastic elastomer showing a tan? peak value in the range of ?20 to 20° C. in a dynamic viscoelasticity test (temperature dependency measurement at 10 Hz) of the elastomer according to JIS K6394, and the peak value being 1 or more.

Abstract: A rubber composition, comprising one or more rubber components, and an oil of a plant in the family Euphorbiaceae in an amount of 1 to 60 parts by mass for the entire amount of the rubber component(s) when the entire amount is regarded as 100 parts by mass. It is preferred that the plant oil is an oil originating from an inedible resource and comprising an unsaturated fatty acid in a proportion of 50% by mass or more of the plant oil.

Abstract: A rubber composition, comprises a rubber component; and a completely amorphous olefin based elastomer having a glass transition temperature Ig of ?40 to 20° C. in an amount of 1 to 40 parts by mass when the entire amount of the rubber component is regarded as 100 parts by mass. It is preferred that the rubber composition further comprises a liquid rubber in an amount of 1 to 40 parts by mass.

Abstract: A rubber composition, comprising a terminal-modified polystyrene butadiene rubber in an amount of 10 to 80 parts by mass when the entire amount of rubber components in the composition is regarded as 100 parts by mass; and a thermoplastic elastomer in an amount of 1 to 20 parts by mass for the 100 parts by mass of the rubber components; the thermoplastic elastomer showing a tan ? peak value in the range of ?20 to 20° C. in a dynamic viscoelasticity test (temperature dependency measurement at 10 Hz) of the elastomer according to JIS K6394, and the peak value being 1 or more.

Abstract: Disclosed is a copolymer including a monomer unit (a) derived from a compound represented by the formula (1) and a monomer unit (b) derived from a compound represented by the formula (2), and having a weight average molecular weight (Mw) of from 1,000 to 50,000 wherein R1 represents a hydrogen atom or a methyl group, R2 represents a hydrogen atom, a linear alkyl group having from 1 to 8 carbon atoms, or a branched alkyl group having from 3 to 8 carbon atoms, R3, R4, R5, R6, R7 and R8 may be the same or different, at least one of those groups represents an aliphatic hydrocarbon group having from 3 to 8 carbon atoms, and the remainder represents a hydrogen atom or an aliphatic hydrocarbon group having 1 or 2 carbon atoms.

Abstract: A rubber composition contains 100 parts by mass of a rubber component comprising diene rubber, and from 1 to 100 parts by mass of a (meth)acrylate polymer having a weight average molecular weight of from 5,000 to 1,000,000 and a glass transition point of from ?70 to 0° C. A pneumatic tire is obtained using the rubber composition.

Abstract: Disclosed is a copolymer including a monomer unit (a) derived from a compound represented by the formula (1) and a monomer unit (b) derived from a compound represented by the formula (2), and having a weight average molecular weight (Mw) of from 1,000 to 50,000 wherein R1 represents a hydrogen atom or a methyl group, R2 represents a hydrogen atom, a linear alkyl group having from 1 to 8 carbon atoms, or a branched alkyl group having from 3 to 8 carbon atoms, R3, R4, R5, R6, R7 and R8 may be the same or different, at least one of those groups represents an aliphatic hydrocarbon group having from 3 to 8 carbon atoms, and the remainder represents a hydrogen atom or an aliphatic hydrocarbon group having 1 or 2 carbon atoms.

Abstract: A rubber composition for adhering a steel cord that improves wet heat-resistant adhesioness, particularly heat-resistant adhesioness, by preventing adhesion deterioration due to heat, as well as initial adhesioness between a steel cord and a rubber, is disclosed. The rubber composition comprising 100 parts by weight of a diene rubber component and from 0.1 to 30 parts by weight of composite graphite particles containing boron, obtained by heating and graphitizing carbon black together with boron or a compound containing boron.

Abstract: A rubber composition for adhering a steel cord that improves wet heat-resistant adhesioness, particularly heat-resistant adhesioness, by preventing adhesion deterioration due to heat, as well as initial adhesioness between a steel cord and a rubber, is disclosed. The rubber composition comprising 100 parts by weight of a diene rubber component and from 0.1 to 30 parts by weight of composite graphite particles containing boron, obtained by heating and graphitizing carbon black together with boron or a compound containing boron.

Abstract: A rubber-filler composite exhibiting low heat build-up, fatigue resistance and heat aging resistance equal to those of a concentrated natural rubber latex, despite using a field latex of a natural rubber and omitting a concentration step is disclosed. The rubber-filler composite is obtained by jetting a field latex of a natural rubber in a form of a high-speed flow having a flow rate of 500 m/sec or more into a mixing chamber while supplying a filler slurry containing a filler to the mixing chamber, thereby separating and removing protein in the field latex from a rubber component and at the same time, mixing the field latex and the filler slurry.

Abstract: In a rubber-filler composite, the filler is uniformly finely dispersed, thereby improving low heat build-up, fatigue resistance and processability of a rubber composition. The rubber-filler composite is obtained by irradiating a filler slurry containing a filler such as carbon black or silica with high amplitude ultrasonic waves having amplitude of 80 ?m or more to finely disperse the filler in the slurry, and mixing the dispersion-treated filler slurry with a concentrated natural rubber latex while conducting irradiation with high amplitude ultrasonic waves having amplitude of 80 ?m or more, followed by coagulating and drying.

Abstract: In a rubber-filler composite, the filler is uniformly finely dispersed, thereby improving low heat build-up, fatigue resistance and processability of a rubber composition. The rubber-filler composite is obtained by irradiating a filler slurry containing a filler such as carbon black or silica with high amplitude ultrasonic waves having amplitude of 80 ?m or more to finely disperse the filler in the slurry, and mixing the dispersion-treated filler slurry with a rubber latex such as a natural rubber latex while conducting irradiation with high amplitude ultrasonic waves having amplitude of 80 ?m or more, followed by coagulating and drying.