Tire tread reinforced with a silica of very low specific surface area

Abstract

A tire tread incorporating an elastomeric composition reinforced with silica, based on at least (phr=parts by weight per hundred parts of diene elastomer): (i) a diene elastomer; (ii) as reinforcing filler, more than 80 phr of an inorganic filler constituted in its entirety or in part by a silica (referred to as LS) having the following characteristics: (a) a BET specific surface area of between 50 and 100 m2/g; (b) an average particle size, dW, of between 50 and 350 nm; (iii) a coupling agent providing the bond between the reinforcing inorganic filler and the diene elastomer; (iv) a vulcanization system based on sulfur. Preferably, this LS silica furthermore has a disagglomeration rate α greater than 5×10−3 μm−1/min (measured in the ultrasound disagglomeration test). Compared with a conventional tread for “Green Tires” reinforced with a silica of higher specific surface area, the tread of the invention has an improved compromise of performances in terms of wear resistance, rolling resistance, grip and drift thrust.

Dependencies are inferred from the claim text.