Tyre comprising circumferential cords for the anchoring of the carcass, method of preparation of such cords

摘要

A pneumatic tyre has sidewall end beads, at least one of which includes: (a) casing reinforcing elements extending from the bead bottom towards the sidewall; (b) at least one layer (4) of circumferential cables (2) at the sides of the reinforcing elements, the cables having a functional elongation (Af) of greater than 4%; and (c) a bonding rubber mixt. (3) between the cables and the reinforcing elements. Also claimed is a process for preparing a cable for a pneumatic tyre involves subjecting a cable of cold worked 0.4-1.0% C steel, covered with a rubber adhesion promoter, to a recovery anneal at between 250 degrees C and the Ac1 temp. for a time sufficient to adjust the functional elongation (Af) to greater than 4%, while controlling the aptitude of the cable for adhesion to a test rubber mixt. before and after the cable prepn. such that the adhesion loss is max. 60%. Further claimed are similar tyres.