This invention relates to a tread rubber composition for tires with the
addition of crosslinked resinous nanoparticles having a high glass
transition temperature (T.sub.g) into elastomeric base polymers. The
invention demonstrates greatly improved handling performance without
deteriorating controllability and stability during high-speed running.
The present invention more specifically discloses a tire which is
comprised of a generally toroidal-shaped carcass with an outer
circumferential tread, two spaced beads, at least one ply extending from
bead to bead and sidewalls extending radially from and connecting said
tread to said beads; wherein said tread is adapted to be
ground-contacting; and wherein the tread is comprised of a rubber
composition comprising: (1) a rubbery polymer; (2) from 1 to 30 parts per
hundred parts of rubber by weight of pre-crosslinked polymer particles,
wherein the pre-crosslinked polymer particles have a mean number average
particle size as determined by light scattering which is within the range
of 30 nm to 500 nm, wherein the pre-crosslinked polymer is comprised of
repeat units that are derived from at least one monomer selected from the
group consisting of acrylate monomers, acrylonitrile monomer, and vinyl
halide monomers, wherein the pre-croslinked polymer is in the form of
core-shell particles having a core and a shell, and wherein the
pre-crosslinked polymer has a glass transition temperature which is
within the range of 30.degree. C. to 200.degree. C.; and (3) 10 to 150
parts per hundred parts of rubber by weight of at least one filler
selected from the group consisting of carbon black and silica.