Tire Tread Rubber Composition for Stable Hardness Over Time

The patent applies parameter changes by carefully controlling the softener content (30-150 parts per 100 parts rubber) and selecting specific softener types to modify the rubber composition's physical and chemical parameters. This optimization ensures the rubber maintains stable hardness characteristics over time while preserving grip performance, directly resolving the contradiction between initial performance and long-term stability.

The patent uses composite materials by combining rubber base polymers with specific softeners and fillers in optimized ratios. This composite approach creates a synergistic effect where the softener components prevent excessive hardening over time while maintaining the rubber's adhesive properties, thus preserving grip performance throughout the tire's service life.

The patent optimizes the softener content parameter within a specific range (30-150 parts per 100 parts rubber) and selects softener types with appropriate molecular structures. This parameter optimization ensures sufficient softness for grip performance while the controlled composition prevents excessive softness that would compromise heat aging resistance, balancing both requirements simultaneously.

The softener acts as an intermediary substance that mediates between the rubber polymer chains, maintaining flexibility and grip performance. By carefully selecting softener types and controlling their content, the patent ensures the intermediary provides sufficient plasticization for grip while not compromising the rubber's thermal stability and aging resistance.