Abstract: A composite cord for reinforcing a tire or other elastomeric article having at least one high strength, substantially inextensible yarn spirally wrapped around a core. The core at room temperature has sufficient strength and elasticity to resist and recover from tension forces on the core required during the processing of the cord and building of the tire. The core is composed of material which loses its tensile strength when subjected to temperatures of vulcanization to permit stretching out of the yarn to allow for substantial elongation of a part or all of the tire and then provide reinforcement of the elongated tire by the stretched out, high strength yarn.

Abstract: A composite cord for reinforcing a tire or other elastomeric article having at least one high strength, substantially inextensible yarn spirally wrapped around a core. The core at room temperature has sufficient strength and elasticity to resist and recover from tension forces on the core required during the processing of the cord and building of the tire. The core is composed of material which loses its tensile strength when subjected to temperatures of vulcanization to permit stretching out of the yarn to allow for substantial elongation of a part or all of the tire and then provide reinforcement of the elongated tire by the stretched out, high strength yarn.

Abstract: A radial spare tire which, upon inflation, stretches from a shape having a reduced diameter adjacent the wheel rim on which the tire is mounted, to a regularly sized radial tire which the spare tire is designed to replace. The tire is molded and vulcanized in an unstretched configuration of reduced size. The stretching of the tire is made possible by the utilization in the carcass and belt plies of reinforcement cords which, during the processing of the cord and building of the tire, have a relatively high modulus of elasticity. When the cords are subjected to vulcanization temperatures, they lose their strength and have a low modulus of elasticity to permit the stretching of the tire to a regular size. The cords then develop a high modulus of elasticity in the stretched condition to provide the required reinforcement of the tire in the inflated regular size condition.