Patent ID: 11912067
Assignee: THE GOODYEAR TIRE & RUBBER COMPANY
Field: Transport (Mechanical engineering)
Classification: CPC B  C | IPC B  C

Claim 17:
18. A tire comprising a belt portion and a tread portion, wherein the tread portion is situated radially outward from the belt portion, wherein the tread portion comprises a radially outer tread cap layer, which is adapted to be ground contacting, and a radially inner tread cap layer arranged between the radially outer tread layer and the belt portion, wherein the radially inner tread cap layer extends under the entire axial width of the radially outer tread cap layer,
wherein the radially outer tread cap layer comprises a first rubber composition having a first shear storage modulus G′1, wherein the first rubber composition includes carbon black and optionally silica, and wherein the weight ratio of the silica to the carbon black is at least 10:1;
wherein the radially inner tread cap layer comprises a second rubber composition having a second shear storage modulus G′2, wherein the second rubber composition is comprised of 75 phr to 90 phr a solution polymerized styrene-butadiene rubber, 10 phr to 25 phr of cis-1,4 polybutadiene rubber having a glass transition temperature which is within the range of −85° C. to −110° C., 45 phr to 70 phr of a filler comprising from 45 phr to 70 phr carbon black and from 0 phr to 25 phr silica, less than 10 phr of plasticizer, 25 phr to 45 phr of a methylene acceptor composition comprising a phenol formaldehyde and an alkyl phenol formaldehyde, 1 phr to 5 phr of a methylene donor composition comprising a hexamethylenetetramine, and 2 phr to 4 phr sulfur;
wherein the second shear storage modulus G′2 is between 3 MPa and 9 MPa higher than the first shear storage modulus G′1;
wherein the first shear storage modulus G′1 ranges from 1 MPa to 3 MPa and the second shear storage modulus G′2 ranges from 4 MPa to 12 MPa, and wherein the first shear storage modulus G′1 and the second shear storage modulus G′2 are determined according to ASTM D5992.