Metal Cord Coating Rubber Composition for Low Heat and Crack Resistance

The patent changes the particle size parameter of carbon black to a specific range (D50: 20-50 nm, D90: 80-120 nm) and controls the aggregate distribution (ΔD50: 10-30 nm) to achieve both low hysteresis loss and high crack resistance. This parameter optimization allows the carbon black to provide reinforcement without excessive hysteresis, resolving the contradiction between energy loss and reliability.

The patent creates a composite system combining carbon black with specific particle size distribution and silica (5-25 parts by mass relative to 100 parts rubber component). This composite approach allows the synergistic effect of multiple fillers to achieve both low heat generation and high crack resistance, overcoming the limitations of using carbon black alone.

The patent optimizes multiple parameters simultaneously: carbon black particle size (D50: 20-50 nm), aggregate distribution (ΔD50: 10-30 nm), and silica content (5-25 parts by mass). This multi-parameter optimization ensures that the filler system provides both low hysteresis loss through fine particle size and sufficient crack resistance through controlled aggregate distribution and silica reinforcement.

The patent creates local quality differences in the rubber composition by controlling the aggregate size distribution of carbon black (ΔD50: 10-30 nm). The narrow aggregate distribution ensures uniform local reinforcement throughout the rubber matrix, providing consistent crack resistance while maintaining low hysteresis loss through the fine primary particle size.