Disclosed is a rubber composition suitable for use as a cap ply rubber composition. The rubber composition comprises: (a) at least one natural or synthetic rubbery polymer; (b) from 0.1 to 20 phr of at least one hydrazide compound; (c) from 0.1 to 10 phr of at least one methylene donor; (d) from 0.1 to 10 phr of at least one methylene acceptor resin; and (e) from 0.1 to 10 phr of zinc oxide is disclosed. A method of making the same is also disclosed.

The invention relates to a tire having a rubber tread of a circumferentially zoned tread including stratified lateral tread zones and peripheral sidewall extensions. The tread zones are comprised of three circumferential load bearing zones, with each zone containing a portion of the running surface of the tread, comprised of an intermedial zone positioned between and two stratified lateral tread zones together and, in addition, peripheral sidewall extensions. The intermedial and stratified lateral zones are comprised of rubber compositions having differentiated 100 C. hot rebound physical properties. The intermedial rubber zone, or layer, overlays a tread base rubber layer and underlies the lateral tread layer zones. The lateral tread zones are stratified in a sense of being separated from each other and also separated from the from the tread base rubber layer by the intermedial rubber layer. The tread includes a peripheral carbon black rich rubber layer as a sidewall extension which extends radially outward from the outer tire sidewall to thereby join a portion of the peripheral tread zone rubber layer and extends to and includes a portion of the running surface of the tread.

The invention relates to a tire with circumferentially zoned tread including peripheral sidewall extensions. The tread zones are comprised of three circumferential load bearing zones, with each zone containing a portion of the running surface of the tread, comprised of an intermedial rubber zone positioned between and extending beneath two stratified lateral tread rubber zones and, in addition, peripheral sidewall extensions. The tread configuration contains a carbon black reinforced tread base rubber layer underlying the intermedial tread rubber zone. The lateral tread rubber zones are therefore spaced apart from each other with the intermedial tread zone therebetween and also at least partially spaced apart from the tread base rubber layer with the intermedial tread zone therebetween. The tread includes a peripheral carbon black reinforced rubber layer as an extension of the tire sidewall which extends radially outward from the outer tire sidewall to thereby join a portion of a lateral tread zone which may extend to and include a portion of the running surface of the tread.

A rubber composition contains at least one elastomer including at least one conjugated diene elastomer, a pre-silanized precipitated silica, a high surface area (e.g., CTAB surface area of at least 200 m.sup.2/g) silica, a tear strength agent, a sulfur-based curing agent, and an accelerator for the curing agent. The rubber composition may be used to form tires.

A tyre (1) for motorcycle wheels is described comprising a tread band (8) of the cap-and-base type comprising a radially outer portion, formed by a central sub-portion (11a) made with a first vulcanized elastomeric material and by a pair of lateral sub-portions (11b, 11c) made with a second vulcanized elastomeric material, and a radially inner portion (12) made with a third vulcanized elastomeric material. The first vulcanized elastomeric material of the central sub-portion (11a) has a dynamic elastic modulus (E) measured at a frequency of 10 Hz and at 23 C. greater than the dynamic elastic modulus (E) measured in the same conditions of the second vulcanized elastomeric material of the lateral sub-portions (11b, 11c) and both such vulcanized elastomeric materials have a respective dynamic elastic modulus (E), again measured at a frequency of 10 Hz and at 23 C., comprised between 5.2 and 6.5 MPa and greater than the dynamic elastic modulus (E) of the third vulcanized elastomeric material, measured in the same conditions. In the tyre (1), the ratios R1 and R2 between the dynamic elastic modulus and the tandelta of the second vulcanized elastomeric material of the lateral sub-portions (11b, 11c) of the radially outer portion and the dynamic elastic modulus and the tandelta of the third vulcanized elastomeric material of the radially inner portion (12) of the tread band (8), respectively measured at a frequency of 10 Hz and at 100 C. and at a frequency of 10 Hz and at 70 C., are comprised between 0.8 and 1.2.

The present invention relates to a pneumatic tire having a tread comprising a tread base layer and a tread cap. The tread cap comprises a first tread cap layer and a second tread cap layer of different polymeric compositions, the tread cap having a central cap zone Z.sub.C and two lateral cap zones Z.sub.L the lateral cap zones Z.sub.L being located axially adjacent to the central cap zone Z.sub.C and on axially opposite sides of the central cap zone Z.sub.C.