| 摘要 |
PURPOSE:To obtain a rubber composition for tire treads improved in performance on the ice, ice and snow performance, abrasion resistance and fracture resistance characteristic by regulating rubber hardness within a prescribed range and blending a thermally infusible granular phenolic resin having methylol groups with the rubber. CONSTITUTION:A rubber composition for tire treads containing (A) 100 pts.wt. diene-based rubber, (B) 2-15 pts.wt. thermally infusible granular phenolic resin having 1-200mum average grain diameter and containing methylol groups, preferably having a high methylol group content, e.g. 7-8wt.% methylol group content and >=10000 molecular weight and (C) 30-80 pts.wt., preferably 35-55 pts.wt. reinforcing agent selected from carbon black and silica. A vulcanized substance of the aforementioned rubber composition satisfies the relation expressed by the formula (E is pts.wt. of an extracted part based on 100 pts. wt. rubber component obtained by extracting the vulcanized rubber with a acetone/ chloroform mixed solvent and then analyzing the extract; F is pts.wt. of the reinforcing agent based on 100 pts.wt. aforementioned rubber component). |
