A pneumatic tire is equipped with at least a tread part, a sidewall part, a bead part, and a carcass extending from tread part through sidewall part to bead part, and provided with a breaker part on the outside of carcass in the radial direction of the tire. The volume resistivity of each of a tread rubber, a sidewall rubber, a breaker rubber, and a carcass rubber formed in the tread part, the sidewall part, the breaker part, and the carcass respectively is set to 1×1012 Ω·cm or more. A conductive layer having volume resistivity of 1×1011 Ω·cm or less is provided between a carcass ply constituting the carcass and the sidewall rubber and has an exposed part to the tire surface. A rubber cement layer contacting with at least a part of the exposed part of the conductive layer and at least a part of the region that becomes a grounding surface in the tread part to the road surface is provided.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a figure exemplifying the right half of a sectional view of the pneumatic tire in the present invention; and
FIG. 2 is an enlarged view of a tread part 2 in a pneumatic tire 1 in the present invention.
Claims
1. A pneumatic tire equipped with at least a tread part, a sidewall part, a bead part, and a carcass extending from said tread part through said sidewall part to said bead part, and provided with a breaker part on the outside of said carcass in the radial direction of the tire,
wherein volume resistivity of each of a tread rubber, a sidewall rubber, a breaker rubber, and a carcass rubber formed in said tread part, said sidewall part, said breaker part, and said carcass respectively is set to 1×1012 Ω·cm or more,a conductive layer having volume resistivity of 1×1011 Ω·cm or less is provided between a carcass ply constituting said carcass and said sidewall rubber andsaid conductive part has an exposed part to the tire surface,and a rubber cement layer contacting with at least a part of said exposed part of said conductive layer and at least a part of the region that becomes a grounding surface in said tread part to the road surface is provided.
2. Pneumatic tire according to claim 1, wherein the thickness of said conductive layer is in the range of 0.2 to 3.0 mm.
3. Pneumatic tire according to claim 1, wherein said conductive layer includes silica.
4. Pneumatic tire according to claim 1, wherein said conductive layer and said rubber cement layer include 100 parts by mass of a diene rubber and 1 to 30 parts by mass per 100 parts by mass of the diene rubber of a compound having an oxyethylene unit.
5. Pneumatic tire according to claim 1, wherein said rubber cement layer has a lower volume resistivity than said tread rubber.
Patent Application
20070227636
