VEHICLE TIRE HAVING A TREAD COMPRISING A HEAT-EXPANDABLE RUBBER COMPOSITION

摘要

The invention relates to a vehicle tire, particularly to a winter tire, the tread of which comprises a rubber composition which is heat-expandable in the non-vulcanized state, and which is expanded in the vulcanized state. In the non-vulcanized state, said composition comprises: a diene elastomer, such as natural rubber and/or polybutadiene; more than 50 pce of a reinforcing filler, such as silica and/or carbon black; 5 to 25 pce of a sodium or potassium (hydrogen) carbonate; and 2 to 20 pce of a carboxylic acid having a melting point of 60° to 220°C, such as e.g. citric acid or stearic acid. The total (hydrogen) carbonate and carboxylic acid content is higher than 10 pce, preferably higher than 15 pce. The combined use of the two latter compounds with said recommended high contents greatly enhances the grip of the tire on melting ice.