AQ Compound II
This a combination of technology to reduce rubber hardening after wearing and heating up. Three methods are used to suppress the aging effect on rubber.
Rubber contains oil , which tends to migrate to the under-tread/casing during a tires life. The surface which loses oil, becauses harder. Bridgestone has replaced partly the oil with a substance that comprises larger molecules which migrate less easily through the rubber.
Polymer chain scission after use due to heat and strain caused by friction and deformation when tire is in motion. Then re-polymerization occurs increasing the rubber hardness and the wet performance will deteriorate. By using link stabilizing agent to prevent re-polymering, rubber will not harden and so maintain the wet performance.
Heat generation during use reactives sulfur and accelerate re-crosslinking with polymer, resulting in rubber hardening and wet performance deterioration. Bridgestone add a special additive to controls the cross-linking by sulfur. Hence restrain rubber from hardening and provide more consistent wet performance.