Lubrication of run-flat tire system

Abstract

A lubricant composition for lubricating an interface between an inner surface of a tire and a safety support ring in a run-flat tire system that includes a lubricating agent selected from glycerol, polyalkylene glycol or combinations thereof and a thixotropic agent. The thixotropic agent is an organoclay comprising a mineral clay mixture treated with an alkyl quaternary ammonium salt, wherein the mineral clay mixture comprises at least one of sepiolite, palygorskite and a smectite and wherein a combined amount of palygorskite and sepiolite in the mineral clay mixture is between about 50 wt. % and about 100 wt. % with a balance of the mineral clay mixture being essentially the smectite. The lubricating agent may also be selected from a copolymer that is a mixture of alkylene oxides, preferably a mixture of ethylene oxide and propylene oxide.

Dependencies are inferred from the claim text.