Provided are a rubber composition having excellent overall performance in terms of fuel economy and bleed resistance as well as good LCA performance (e.g., reduction of CO.sub.2 emissions), and a tire including the composition. A rubber composition containing a plant oil satisfying the conditions (1)-(4): (1) it is liquid at 23° C.; (2) it has a GPC weight-average molecular weight of more than 800; (3) when it is 3-fold diluted with THF, it satisfies the following relationship with respect to the absorbances at 450 nm and 600 nm measured with a spectrophotometer: Absorbance at 450 nm−Absorbance at 600 nm 0.05; and (4) it satisfies the following relationship with respect to the weights before and after passing 100 g of the plant oil at 23-30° C. through 20 mesh plain weave wire cloth: (Weight after passing through plain weave wire cloth)/(Weight before passing through plain weave wire cloth)×100≥99.0.

Provided are a rubber composition having excellent overall performance in terms of fuel economy and bleed resistance as well as good LCA performance (e.g., reduction of CO.sub.2 emissions), and a tire including the composition. A rubber composition containing a plant oil satisfying the conditions (1)-(4): (1) it is liquid at 23° C.; (2) it has a GPC weight-average molecular weight of more than 800; (3) when it is 3-fold diluted with THF, it satisfies the following relationship with respect to the absorbances at 450 nm and 600 nm measured with a spectrophotometer: Absorbance at 450 nm−Absorbance at 600 nm 0.05; and (4) it satisfies the following relationship with respect to the weights before and after passing 100 g of the plant oil at 23-30° C. through 20 mesh plain weave wire cloth: (Weight after passing through plain weave wire cloth)/(Weight before passing through plain weave wire cloth)×100≥99.0.

A rubber resin material with high thermal conductivity and a metal substrate with high thermal conductivity are provided. The rubber resin material includes inorganic fillers and a rubber resin composition with high thermal conductivity. The rubber resin composition with high thermal conductivity includes 40 wt % to 70 wt % of a liquid rubber, 10 wt % to 30 wt % of a polyphenylene ether resin, and 20 wt % to 40 wt % of a crosslinker. A molecular weight of the liquid rubber ranges from 800 g/mol to 6000 g/mol. The inorganic fillers undergo a surface modification process to have at least one of an acryl group and an ethylene group.

A rubber resin material with high thermal conductivity and a metal substrate with high thermal conductivity are provided. The rubber resin material includes inorganic fillers and a rubber resin composition with high thermal conductivity. The rubber resin composition with high thermal conductivity includes 40 wt % to 70 wt % of a liquid rubber, 10 wt % to 30 wt % of a polyphenylene ether resin, and 20 wt % to 40 wt % of a crosslinker. A molecular weight of the liquid rubber ranges from 800 g/mol to 6000 g/mol. The inorganic fillers undergo a surface modification process to have at least one of an acryl group and an ethylene group.

An object of the present invention is to provide a golf ball having a decreased spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) two or more α,β-unsaturated carboxylic acids having 3 to 14 carbon atoms and having no substituent group at a carbon atom bonding to the carboxy group, and/or a metal salt thereof, and (c) a crosslinking initiator.

An object of the present invention is to provide a golf ball having a decreased spin rate on driver shots. The present invention provides a golf ball comprising a spherical core and at least one cover layer covering the spherical core, wherein the spherical core is formed from a rubber composition containing (a) a base rubber, (b) two or more α,β-unsaturated carboxylic acids having 3 to 14 carbon atoms and having no substituent group at a carbon atom bonding to the carboxy group, and/or a metal salt thereof, and (c) a crosslinking initiator.

A rubber composition for a tire, which does not require the addition of a compound when synthesizing rubber component and the modification of a rubber component, and a winter tire using the rubber composition are provided. The rubber composition for a tire contains fine particles of rotaxane having a straight chain molecule, acyclic molecule clathrating the straight chain molecule and blocking groups arranged at both terminals of the straight chain molecule such that the cyclic molecule does not desorb from the straight chain molecule, covered with silica; a rubber component comprising styrene-butadiene rubber; and at least one of carbon black and silica, wherein the total content of the fine particles, the carbon black and the silica (excluding silica covering rotaxane) is 70 to 150 parts by mass per 100 parts by mass of the rubber component.

A rubber composition for a tire, which does not require the addition of a compound when synthesizing rubber component and the modification of a rubber component, and a winter tire using the rubber composition are provided. The rubber composition for a tire contains fine particles of rotaxane having a straight chain molecule, acyclic molecule clathrating the straight chain molecule and blocking groups arranged at both terminals of the straight chain molecule such that the cyclic molecule does not desorb from the straight chain molecule, covered with silica; a rubber component comprising styrene-butadiene rubber; and at least one of carbon black and silica, wherein the total content of the fine particles, the carbon black and the silica (excluding silica covering rotaxane) is 70 to 150 parts by mass per 100 parts by mass of the rubber component.

A rubber compound for the preparation of portions of pneumatic tyres comprising a cross-linking unsaturated chain polymer base, a filler system and a vulcanization system. The filler system comprises (a) a first carbon black having a surface area less than or equal to 170 m.sup.2/gr in a quantity greater than or equal to 25 phr; (b) a second carbon black having a surface area greater than or equal to 250 m.sup.2/gr in a quantity such that the ratio between the quantity of the first carbon black and the quantity of the second carbon black is greater than or equal to 3 and less than or equal to 10; (c) a carbon black dispersing agent in a quantity of less than or equal to 1 phr.

A rubber compound for the preparation of portions of pneumatic tyres comprising a cross-linking unsaturated chain polymer base, a filler system and a vulcanization system. The filler system comprises (a) a first carbon black having a surface area less than or equal to 170 m.sup.2/gr in a quantity greater than or equal to 25 phr; (b) a second carbon black having a surface area greater than or equal to 250 m.sup.2/gr in a quantity such that the ratio between the quantity of the first carbon black and the quantity of the second carbon black is greater than or equal to 3 and less than or equal to 10; (c) a carbon black dispersing agent in a quantity of less than or equal to 1 phr.