Pneumatic tire including a protective rubber layer on the outer surface of the sidewalls

Claim 1

A pneumatic tire comprising: a tread portion with a pair of edges; a pair of axially spaced bead portions each with a bead core; a pair of sidewall portions extending from the edges of the tread portion to the bead portions; a carcass extending between the bead portions; said tread portion having a tread rubber layer disposed radially outside the carcass; each of said sidewall portions including a sidewall rubber layer disposed axially outside the carcass, the sidewall rubber layer being of softer material than the tread rubber layer; a protective rubber layer disposed on the outer surface of each of the sidewall rubber layers defining a portion of the outer surface of each sidewall portion; the protective rubber layer having a radial outer edge that ends near the edge of the tread rubber layer and a radial inner edge located radially inward of the maximum carcass width point of the tire and within the sidewall portion; the protective rubber layer being made of a fiber-reinforced rubber composition containing 10 to 50 parts by weight of short fibrous reinforcements, 20 to 70 parts by weight of carbon black, and 100 parts by weight of rubber base consisting of 20 to 100 parts by weight of natural rubber or isoprene rubber and 80 to 0 parts by weight of butadiene rubber; the short fibrous reinforcements oriented at an angle in the range of between 0 to 20 degrees with respect to the tire circumferential direction.