| 摘要 |
[Subject Matter] To provide a rubber composition capable of making well- balanced improvements to wet grip performance, wear resistance and tensile strength, and to provide a pneumatic tire having a tread produced by using the rubber composition. [Solution(s)] A rubber composition, containing a rubber component made of an oil-extended butadiene rubber having a cis content of 95 mol% or greater, a vinyl content of 1.2 mol% or less and a weight-average molecular weight of 530,000 or greater, and/or a styrene-butadiene rubber having a bound styrene content of 10ˆ¼60 mass% and a weight-average molecular weight of 800,000 or greater; an inorganic reinforcement agent represented by the formula below and having a nitrogen adsorption specific surface area of 10ˆ¼60 m 2 /g or greater; and silica having a nitrogen adsorption specific surface area of 100 m 2 /g or greater and/or carbon black having a nitrogen adsorption specific surface area of 100 m 2 /g or greater. To produce such a rubber composition, the oil-extended butadiene rubber is synthesized using a rare-earth element-based catalyst, the total content of the oil-extended butadiene rubber and the styrene-butadiene rubber is 10ˆ¼100 mass% of the rubber component, and based on 100 parts by mass of the rubber component, the content of the inorganic reinforcement agent is 1ˆ¼70 parts by mass and the total content of the silica and carbon black is at least 50 parts by mass.
€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ€ƒ mM·xSiO y ·zH 2 O
(in the formula, "M" represents at least one metal selected from the group consisting of Al, Mg, Ti, Ca, Zr, an oxide of the metal thereof and a hydroxide of the metal thereof, "m" is a whole number of 1ˆ¼5, "x" is a whole number of 0ˆ¼10,
"y" is a whole number of 2ˆ¼5, and "z" is a whole number of 0ˆ¼10) |
