TIRE HAVING TREAD BAND COMPRISING SCULPTURE ELEMENTS WITH RIGID SIDEWALLS HAVING HEAT-EXPANDABLE RUBBER RUBBER IN RAW CONDITION, OR FOAM RUBBER IN COOKED STATE.

摘要

Tire, in the green or cooked state, the tread of which comprises: a plurality of sculpting elements (1) formed of a first rubber material called base material (MB) delimited by cutouts (3, 4); - These tread elements comprising a contact face (2) intended to come into contact with the road during the rolling of the tire, and at least one side wall (13, 14, 15, 16); on at least one side wall of all or some of said carving elements, the base material being covered at least in part by a layer of a second rubber material called a cover material (MR), different from the base material, which comprises at least one rubber composition, characterized in that said rubber composition of the covering material is heat-expandable in the green tire, in the form of foam rubber in the baked tire, and in that it comprises, in the green and uncured tire, at least: - 50 to 100 phr of a copolymer based on styrenic units and butadiene units, whose glass transition temperature is higher at -40 ° C; optionally, 0 to 50 phr of another diene elastomer; - more than 50 phr of a reinforcing filler; more than 25 phr of a hydrocarbon plasticizing resin whose glass transition temperature is greater than 20 ° C .; optionally, less than 20 phr of a liquid plasticizer.