Recapping butyl tires

Claim 1

IN A METHOD OF RECAPPING A USED TIRE MADE OF SULFURCURED ISOBUTYLENE-ISOPRENE COPOLYMER RUBBER CONTAINING 0.5-15% ISOPRENE WHEREIN AN UNVULCANIZED RECAPPING MATERIAL, COMPRISING A HIGHLY UNSATURATED RUBBERY POLYMER CONTAINING AT LEAST 25% OF A DIOLEFIN SELECTED FROM THE GROUP CONSISTING OF BUTADIENE AND ISOPRENE COMPOUNDED FOR COMPLETE VULCANIZATION WITH SULFUR WHEN HEATED AT A TEMPERATURE 275*-330*F. FOR A PERIOD OF 40 MIN. TO 8 HOURS, IS APPLIED TO SAID CURED TIRE AND SUBJECTED TO THE JUST-MENTIONED HEATING CONDITIONS, WHEREBY THE TIRE IS RECAPPED WITH SAID HIGHLY UNSATURATED RUBBERY POLYMER, THE IMPROVEMENT COMPRISING INTERPOSING, BETWEEN THE SURFACE OF THE CURED TIRE TO BE RECAPPED AND SAID RECAPPING MATERIAL, A LAYER OF TIEGUM COMPRISING A HIGHLY UNSATURATED RUBBERY POLYMER AS PREVIOUSLY DEFINED CONTAINING NO VULCANIZING AND ACCELERATING INGREDIENTS WHEREBY THE TIE GUM IS UNVULCANIZABLE UNDER THE PREVIOUSLY MENTIONED HEATING CONDITIONS, THE SAID TIE GUM BEING INTERPOSED BEFORE CARRYING OUT THE SAID HEATING, WHEREBY THE ADHESION BETWEEN THE SAID RECAPPING MATERIAL AND THE CURED TIRE IS ENHANCED, THE SAID PERCENTAGES BEING BY WEIGHT.