Abstract: Different sized, first and second domes are stacked, one atop the other on the surface of a rib or tread block of a tire. The lower, first dome spans a larger area of the tread. In one embodiment, the first dome covers the entire tread block or extends laterally across a rib. The upper, second dome is located on top of the first dome and spans only a portion of the first dome. The domes are either concentric or offset, or can be elliptical with the major axes of the ellipses oriented such that the major axes are optimized for a specific tread block or rib geometry. The major axes of the ellipses may be oriented parallel to or perpendicular to an axis of stiffness of the tread block or rib.

Abstract: A method for stabilizing a natural rubber such as guayule. The method includes the step of introducing at least one of an Extraction Curves for Guayule Rubber Samples amine and a phenolic anti-oxidant, such as MADA, to a latex form of the rubber under conditions such that the anti-oxidant becomes chemically bound to the rubber. The method includes the further step of subsequently treating the rubber to remove at least a substantial portion of entrained resins. The method can yield a rubber composition of, for example, guayule rubber and including an anti-oxidant chemically bound thereto. The resultant rubber can be suitable for use in tire construction.

Abstract: A tire tread composition includes a quantity of an elastomer including guayule natural rubber, and a quantity of a hydrocarbon resin substantially evenly distributed throughout the elastomer. The elastomer of the tire tread composition may consist entirely of guayule natural rubber. The hydrocarbon resin may be selected to have a predetermined miscibility in the guayule natural rubber. The predetermined miscibility is measured by a deviation of actual Tg from predicted Tg for either the tire tread composition or an elastomer-resin mixture consistent with the elastomer and resin used in the tire tread composition. In particular, the predetermined miscibility in the guayule natural rubber is less than about six percent (6%) deviation in the actual Tg from the predicted Tg at a 20 phr loading.

Abstract: A process for forming an epoxidized rubber including dissolving a rubber in a solvent and epoxidizing the rubber in the presence of an epoxidation reagent. The solvent is selected such that the rubber is soluble therein but the epoxidized rubber precipitates.

Abstract: A visual wear indicating feature is incorporated into the tread pattern to provide progressive, incremental indications to the customer regarding the amount of useable tread remaining on the tire.