Method of retreading vehicle tires using microwave heating

Claim 1

Method of retreading vehicle tires using a prevulcanized tread and a tiegum, characterized in that (a) the tire carcass (3) is prepared and scraped in a manner known per se, and any damage is repaired; (b) a strip of rubber-base bonding material (2), whose dielectric loss factor ε"=ε·tanδ, where ε designates the dielectric constant and δ is the dielectric loss angle, at a selected vulcanization temperature for the bonding strip is greater than the loss factor of the prevulcanized tread, is applied to the tire carcass; (c) the prevulcanized tread (1) is applied on top of the bonding strip (2) and the assembly comprising carcass, bonding strip and tread is joined together by means of a roller device, the tire is provided with an inner tube (4,15) for water, is mounted on a rim (6,11) and is provided with an outer tube (outer cover) (16, FIG. 10 and FIG. 9), provided with an air evacuation outlet; (d) the entire tire assembly is placed in an autoclave between two pressure plates (10), the inner tube (15) is filled with hot water to a pressure of about 750 kPa/cm 2 and the autoclave chamber is filled with air to a pressure of about 500 kPa/cm 2 ; and (e) the assembly comprising carcass, bonding strip and tread is set in rotation and is vulcanized together by means of microwave energy from a microwave applicator (17) disposed inside the autoclave.