| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a rubber composition for a cap tread of truck and bus tires with which low fuel consumption performance, abrasion resistance, rubber strength and wet grip performance are improved in good balance.SOLUTION: There is provided a rubber composition for a cap tread of truck and bus tires which comprises a rubber component, silica (A) having a nitrogen adsorption specific surface area of 100 m/g or less and silica (B) having a nitrogen adsorption specific surface area of 180 m/g or more, wherein the content of a conjugated diene-based polymer having a conjugated diene-based monomer unit, a substituted amino silicon group-containing monomer unit, a substituted amino group- or nitrogen-containing hetero group-containing monomer unit is 5 mass% or more in 100 mass% of the rubber component, the total content of the silica (A) and (B) is 5 to 150 pts.mass based on 100 pts.mass of the rubber component and the content of the silica (A) and (B) satisfies the following expression: (the content of silica (A))×0.2≤(the content of silica (B))≤(the content of silica (A))×6.5.</p> |
