Pirelli Tyre S.p.a.

Pirelli Coordinamento Pneumatici S.p.a.

Pirelli Pneumatici S.p.a.

Pierluigi De Cancellis

Marco Nahmias

Gaetano Lo Presti

Thomas Hanel

Stefano Testi

Piero Losi

Rodolfo Noto

Alberto Scurati

Giuseppina Ratti

Claudio Lacagnina

Antonio Monterosso

Alessio Longoni

Francesca Baione

Francesco Parazzoli

Juergen Wagemann

Marianna Zinna

Elena Prandini

Angela Lostritto

Antonio Ciancio

Paolo Quinzani

Cinzia De Vita

The present invention relates to a tire () for vehicle wheels comprising a tire component comprising a crosslinked elastomeric material obtained by crosslinking a crosslinkable elastomeric composition, wherein said elastomeric composition comprises a polymer blend comprising (a) 50 to 95 percent by weight of a first elastomeric polymer and (b) 5 to 50 percent by weight of a second elastomeric polymer based on the total weight of the polymer blend. The second elastomeric polymer (b) is obtainable by (i) anionic polymerization of at least one conjugated diene monomer and one or more a-olefin monomer(s) in the presence of a polymerization initiator in an organic solvent, and (ii) coupling the polymer chains obtained in (i) by a coupling agent. The second elastomeric polymer (b) has a weight-average molecular weight (Mw) in the range of 5,000-40,000 g/mol and a coupling rate of at least 50 percent by weight.

Tire for vehicle wheels

A process for producing tyres including building a green tyre having two bead structures. Each bead structure includes a bead filler. The bead filler or another rigid component of the green tyre includes a final elastomeric compound produced by the following: feeding elastomeric polymer and reinforcement filler to a first batch mixing device; mixing and dispersing the reinforcement filler in the elastomeric polymer and unloading the obtained elastomeric compound; feeding the obtained elastomeric compound, along with at least 5 phr of reinforcement resin, to a continuous mixing device of intermeshing and co-rotating twin-screw or multi-screw type or of planetary type; mixing the reinforcement resin in the elastomeric compound and unloading the obtained elastomeric compound; and feeding the obtained elastomeric compound along with the components capable of facilitating the cross-linking to a second batch mixing device and mixing to obtain the final elastomeric compound. The first and second batch mixing device have two counterrotating rotors.

Process for producing tyres

A pneumatic tire has a carcass structure having at least one carcass ply and at least one annual reinforcing structure associated with the carcass ply, a tread band made of an elastomeric material at a radially outer position with respect to the carcass structure, a belt structure interposed between the carcass structure and the tread band and a pair of axially opposite side walls on the carcass structure, wherein the tread band has i) at least one first sector, radially extending, substantially of a first elastomeric material; ii) a plurality of second sectors radially extending, positioned at axially opposite sides of the at least one first sector and substantially of a second elastomeric material; iii) at least one longitudinal groove formed in the at least one first sector and extending substantially for the entire circumferential development of the tread band, wherein the first elastomeric material has a modulus of elasticity under compression at 23&#xb0; C. greater than the modulus of elasticity under compression at 23&#xb0; C. of the second elastomeric material, and wherein the modulus of elasticity under compression at 23&#xb0; C. of the first elastomeric material is about 20 to about 80 MPa.

Pneumatic tire and process for its manufacture

A vulcanizable rubber composition is described comprising a cross-linkable unsaturated chain polymeric base, wherein is incorporated at least one organic compound, solid at room temperature, selected from the group comprising: amorphous or semicrystalline polymers, oligomers, low-molecular weight organic substances and mixtures thereof, which compound is substantially insoluble in the polymeric base and shows a first or second order transition temperature of from 80 to 160&deg; C. Such rubber composition allows the manufacture of treads with either a low rolling resistance at the temperature of normal use of the tire (40&deg;-70&deg; C.), or a high grip when the tread is subjected to thermal stresses exceeding such temperatures.

Vulcanizable rubber composition for treads of vehicle tires

Growing community of inventors

Milan, Italy

Pierluigi De Cancellis