Pneumatic vehicle tire with radial ply carcass and tread member composed of a base layer closer to the tire axis and a cap layer arranged on top thereof

Claim 1

A pneumatic vehicle tire comprising: a radial ply carcass defining lateral regions, two shoulder regions, a crown region and a tire axis; two side walls each covering a respective one of said lateral regions of said radial ply carcass; a tread member covering said crown region of said carcass and defining a roadway-contacting portion; said tread member comprising a base layer positioned closer to said tire axis of said carcass and a cap layer arranged on top of said base layer; said cap layer being profiled and constituting said roadway-contacting portion of the tread member; said base layer forming a trough accommodating said cap layer; said trough being bounded by two trough shoulders each one of which bounds a related one of said two shoulder regions of the tire adjacent the cap layer; a belt comprising at least one rubberized cord ply embedded between said tread member and said crown region of said carcass; said base layer defines said trough shoulders; said trough shoulders being constituted by a plurality of members in order to improve the rolling properties of the tire in the region of said trough shoulders; the pneumatic tire defining a median equatorial plane; said trough shoulders comprise portions which are situated furthest from said median equatorial plane; and said furthest situated portions are made of a rubber mixture which is very similar to a rubber mixture from which said side walls are formed.