Conductive tire

Abstract

The present invention provides a tire having a tread and a pair of sidewalls extending from each of two axial ends of the tread. At least in the innermost ply in the radial direction among at least one ply, it is made of a conductive rubber composition and covers at least the inner surface in the radial direction of the innermost ply in the radial direction among at least one ply 23. An edge cover layer is provided that extends up to an axial distance L measured from the axial end of the innermost ply in the radial direction among at least one ply. At least one of the sidewalls extends axially together with the carcass down to an axial distance Le directly below the innermost ply in the radial direction. The axial distance L is larger than the axial distance Le, and the edge cover layer provided with the innermost ply in the radial direction has a portion in contact with the carcass. The axial distance L is at least 10.0 mm or more larger than the axial distance Le.

Description

Technical Field

[0001] The present invention relates to a tire. More particularly, the present invention relates to a tire having improved conductivity while maintaining manufacturing efficiency.

Background Art

[0002] In tires designed for high-speed driving, particularly in passenger car tires, it is now common to incorporate an additional ply of circumferentially oriented cords. This ply may also be positioned above the crown reinforcement ply at a commonly used angle. In such a configuration, the ply of circumferentially oriented cords is the radially outermost ply of the tire crown.

[0003] In recent years, from the viewpoints of economic and environmental considerations, tires that provide fuel efficiency have been demanded. As a means for obtaining such tires, reducing the rolling resistance of tires has attracted attention. As a method for effectively reducing the rolling resistance to obtain a tire, it has been proposed to reduce the hysteresis loss, which is a major cause of the rolling resistance. Since manufacturing a material with low hysteresis loss has an adverse effect on manufacturing efficiency, tire manufacturers are trying to maintain the overall manufacturing efficiency, and one way to achieve such manufacturing efficiency is to reduce the number of semi-finished materials in the factory.

[0004] European Patent No. 0931676 discloses a pneumatic tire having a circumferentially extending ply support strip disposed radially between the carcass ply and the innerliner in each tire shoulder region between the sidewall region and the tread region, the ply support strip comprising a rubber compound containing short discontinuous fibrillated aramid fibers in an amount between 7 and 15 parts by weight per 100 parts by weight of rubber.

[0005] European Patent No. 2749434 discloses a pneumatic tire having a pair of sidewalls, the outer ends of which are located axially inward of the ends of the belt so as to integrate a cushion layer with the sidewalls. U.S. Publication No. 2017 / 120682 discloses a tire having a crown reinforcement including two working crown layers of unequal axial width. A layer C of rubber compound is disposed between the ends of the working crown layers. A second layer S of polymer compound is in contact with at least one working crown layer and a carcass reinforcement, and the carcass reinforcement includes a layer of circumferential reinforcing elements arranged radially between the two working crown layers. The distance d between the end of the axially narrowest working layer and the working layer separated from that layer by layer C is 1.1φ < d < 2.2φ, where φ is the diameter of the reinforcing elements in the meridian plane. The second layer S is composed of a filled elastomer mixture having a macrodispersion coefficient Z ≧ 65 and a maximum tan(δ) value less than 0.100. Its complex dynamic shear modulus G * measured at 10% and 60 °C for the return cycle is greater than 1.35 MPa. U.S. Publication No. 2014 / 230986 discloses a tire that achieves weight reduction without degrading the internal pressure maintenance performance. This tire includes a liner located inside the carcass. The liner includes a first inner liner that extends along the carcass between one bead and the other bead and extends inwardly therebetween, and a pair of second inner liners that extend substantially radially inward from the ends of the belt along the first inner liner. The second inner liners are located between the first inner liner 66 and the carcass. The first inner liner is formed by crosslinking a first rubber composition. The base rubber of the first rubber composition includes butyl rubber. Each second inner liner is formed by crosslinking a second rubber composition. The base rubber of the second rubber composition includes diene rubber.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, in the solutions disclosed in these documents, since the conductive path is interrupted at the sidewall, the conductivity of the tire decreases, which in turn results in an excess of the reference electrical resistance threshold. Such a situation becomes particularly important when using a low hysteresis loss composition in combination with a calendering mixture for the belt. Therefore, it is required to improve the conductivity of the tire without reducing the manufacturing efficiency of such a tire by reducing the number of semi-finished products.

[0008] Therefore, there is a need for a tire that improves conductivity without reducing manufacturing efficiency by reducing the number of semi-finished products.

Means for Solving the Problems

[0009] Definitions

[0010] “Radial / direction” means a direction / orientation perpendicular to the rotation axis of the tire. This direction / orientation corresponds to the direction of the thickness of the tire.

[0011] “Axial / direction” means a direction / orientation parallel to the rotation axis of the tire.

[0012] “Circumferential / direction” means a direction / orientation tangent to any circle centered on the rotation axis. This direction / orientation is perpendicular to both the axial / direction and the radial / direction.

[0013] “Tire” means any type of elastic tire, whether or not it is subjected to internal pressure.

[0014] The "tread" of a tire means the amount of rubber material delimited by the sidewall and two main surfaces, one of the two main surfaces being intended to come into contact with the ground when the tire rotates.

[0015] A "ply" is a layer of material such as nylon, polyester or steel, arranged parallel to each other at a given pitch in the form of cables, wires or strings and coated with a rubber material.

[0016] "Conductivity" is evaluated by the electrical resistance of the tire measured according to the WdK110 test, meaning that the lower the electrical resistance, the higher the conductivity.

[0017] Therefore, an object of the present invention is to provide a tire that improves conductivity without reducing manufacturing efficiency by reducing the number of semi-finished products.

[0018] The present invention provides a tire having a tread intended to contact the ground via a contact surface during rotation and a pair of sidewalls extending from each of two axial ends of the tread, the tire comprising at least one ply disposed radially inward of the tread, the at least one ply comprising a plurality of parallel reinforcing elements extending at an angle A with respect to the circumferential direction of the tire, the angle A being greater than 10 degrees, the tire further comprising a carcass disposed radially inward of the at least one ply, and at least the radially innermost ply among the at least one ply is made of a conductive rubber composition and covers at least the radially inner surface of the radially innermost ply among at least one ply of plies 23, and an edge cover layer is provided that extends up to an axial distance L measured from the axial end of the radially innermost ply among the at least one ply, at least one of the sidewalls, together with the carcass, extends downward directly below the radially innermost ply among the at least one ply up to an axial distance Le measured from the axial end of the radially innermost ply among the at least one ply, the axial distance L being greater than the axial distance Le, the edge cover layer provided for the radially innermost ply among the at least one ply has a portion in contact with the carcass, and the axial distance L is at least 10.0 mm greater than the axial distance Le.

[0019] This configuration enables improvement in conductivity without reducing manufacturing efficiency by reducing the number of semi-finished products.

[0020] Since at least one of the sidewalls, together with the carcass, extends downward directly below the radially innermost ply among the at least one ply, it is possible to replace the material disposed directly below the radially innermost ply among the at least one ply in the case of a normal tire structure with the sidewall, and thus it is possible to improve manufacturing efficiency by reducing the number of semi-finished products.

[0021] In at least the innermost ply in the radial direction among at least one ply, an edge cover layer is provided that at least covers the inner surface in the radial direction of the innermost ply in the radial direction among at least one ply. Therefore, separation between the ply and the carcass can be avoided, and thus the durability performance can be improved.

[0022] The edge cover layer made of a conductive rubber composition, in which the innermost ply in the radial direction among at least one ply is provided, has a portion in contact with the carcass. Therefore, electric charges can pass through the carcass via the edge cover layer, and thus the conductivity of the tire can be improved.

[0023] Since the axial distance L is at least 10.0 mm or more greater than the axial distance Le, the conductivity of the tire can be improved.

[0024] When this axial distance L is greater than the axial distance Le by less than 10.0 mm, there is a risk that the contact between the edge cover layer and the carcass will be insufficient to form a sufficient conductive path.

[0025] This distance L is preferably at least 11.0 mm or more greater than the axial distance Le, more preferably at least 12.0 mm or more greater than the axial distance Le, and still more preferably at least 15.0 mm or more greater than the axial distance Le.

[0026] In another preferred embodiment, the axial distance Le is at most equal to 15.0 mm.

[0027] When this axial distance Le is greater than 15.0 mm, there is a risk that the total width of the semi-finished product of the sidewall will become too large and the manufacturing efficiency will decrease. By setting this axial distance Le to at most 15.0 mm, it is possible to improve the manufacturing efficiency of the tire.

[0028] This axial distance Le is preferably equal to at most 13.0 mm, more preferably equal to at most 12.0 mm, and even more preferably equal to at most 10.0 mm.

[0029] In another preferred embodiment, the edge cover layer further covers at least up to the range of the axial distance L measured from the axial end of the radially innermost ply among at least one ply or less than that, and covers the axial outermost surface and the radial outer surface of the radially innermost ply among at least one ply.

[0030] According to this configuration, the edge cover layer that covers the axial outermost surface and the radial outer surface can prevent not only the separation between the ply and the carcass but also the separation between the plies, so that it is possible to improve the durability performance.

[0031] In another preferred embodiment, at least two radially adjacent plies are provided in the tire, and an edge cover layer that covers the edge portion of each of the at least two plies is provided.

[0032] According to this configuration, the edge cover layer that covers the edge portion of each of the at least two plies can prevent not only the separation between the ply and the carcass but also the separation between the plies, so that it is possible to improve the durability performance.

[0033] In another preferred embodiment, one edge cover layer of the radially adjacent plies has a portion that contacts the other edge cover layer of the radially adjacent plies.

[0034] According to this configuration, the edge cover layer that covers the edge portion of each of the radially adjacent plies can prevent not only the separation between the ply and the carcass but also the separation between the plies, and at the same time can reinforce the conductive path to the carcass, so that it is further possible to improve the durability performance and the conductivity at the same time.

[0035] In another preferred embodiment, the volume resistivity of the conductive rubber composition constituting the edge cover layer is at most 5.00×105 is equal to Ω·cm.

[0036] If this volume resistivity of the conductive rubber composition is greater than 5.00×10 5 Ω·cm, there is a risk that the edge cover layer cannot function efficiently as a conductive path to the carcass. By setting this volume resistivity of the conductive rubber composition to a maximum of 5.00×10 5 Ω·cm, it is possible to improve the conductivity of the tire.

[0037] This volume resistivity of the conductive rubber composition constituting the edge cover layer is preferably at most 4.00×10 5 Ω·cm, more preferably at most 3.75×10 5 Ω·cm.

[0038] In another preferred embodiment, the tire further comprises at least one conductive path opening to the contact surface.

[0039] According to this configuration, since the charge can move to the ground through at least one conductive path opening to the contact surface, it is possible to further improve the conductivity of the tire.

[0040] According to the above configuration, by reducing the number of semi-finished products, it is possible to provide a tire that improves conductivity without reducing manufacturing efficiency.

[0041] Other features and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings showing embodiments of the present invention as non-limiting examples.

Brief Description of the Drawings

[0042]

Figure 1

Figure 2

Figure 3

Figure 4

BEST MODE FOR CARRYING OUT THE INVENTION

[0043] Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

[0044] The tire 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2.

[0045] FIG. 1 is a schematic cross-sectional view of a tire according to the first embodiment of the present invention. FIG. 2 is a schematic enlarged view showing the portion denoted by II in FIG. 1. The portions other than those shown in FIGS. 1 and 2 have a typical radial tire structure, and thus the description of such portions is omitted.

[0046] The tire 1 is a tire having a tread 4 intended to contact the ground via a contact surface 41 during rotation, and a pair of sidewalls 6 (only one is shown in FIG. 1) extending from each of the two axial ends of the tread 4. The tire 1 includes at least one ply 3 disposed radially inside the tread 4. This at least one ply 3 includes a plurality of parallel reinforcing elements (not shown) extending at an angle A (not shown) with respect to the circumferential direction of the tire. When applied to a passenger car tire, this angle A is often greater than 10 degrees and less than 45 degrees. In the present embodiment, the tire 1 includes two plies 3a and 3b, and the angle A is 25 degrees.

[0047] As shown in FIGS. 1 and 2, the tire 1 further includes a carcass 2 disposed radially inside at least one ply 3.

[0048] As shown in FIG. 2, at least in the innermost ply 3a in the radial direction among at least one ply 3, there is provided an edge cover layer 5 made of a conductive rubber composition, which at least covers the inner surface in the radial direction of the innermost ply 3a in the radial direction among at least one ply 3 and extends up to the axial distance L measured from the axial end of the innermost ply 3a in the radial direction among at least one ply 3. At least one of the sidewalls 6, together with the carcass 2, extends downward directly below the innermost ply 3a in the radial direction among at least one ply 3 up to the axial distance Le measured from the axial end of the innermost ply 3a in the radial direction among at least one ply 3. The axial distance L is larger than the axial distance Le. The axial distance L is at least 10.0 mm larger than the axial distance Le. The axial distance Le is at most equal to 15.0 mm. In the present embodiment, the axial distance Le is 7.0 mm, and the axial distance L is 16.0 mm larger than the axial distance Le.

[0049] As shown in FIG. 2, the edge cover layer 5 further covers the axially outermost surface and the radially outer surface of the innermost ply 3a in the radial direction among at least one ply 3 up to the axial distance L or less measured from the axial end of the innermost ply 3a in the radial direction among at least one ply 3.

[0050] As shown in FIG. 2, the edge cover layer 5 provided with the innermost ply 3a in the radial direction among at least one ply 3 has a portion in contact with the carcass 2.

[0051] The volume resistivity of the conductive rubber composition constituting the edge cover layer 5 is at most equal to 5.00×10 5 Ω·cm. In the present embodiment, the volume resistivity of the conductive rubber composition constituting the edge cover layer 5 is 3.50×10 5 Ω·cm.

[0052] At least one of the sidewalls 6 extends together with the carcass 2 downward directly beneath the radially innermost ply 3a among at least one ply 3. Therefore, in the case of a normal tire structure, the material that is disposed directly beneath the radially innermost ply 3a among at least one ply 3 can be replaced with the sidewall 6. Thus, it is possible to improve the manufacturing efficiency by reducing the number of semi-finished products.

[0053] At least one ply 3, and at least the radially innermost ply 3a among them, is provided with an edge cover layer 5 that at least covers the radially inner surface of the radially innermost ply 3a among at least one ply 3. Therefore, separation between the ply 3 and the carcass 2 can be avoided, and thus it is possible to improve the durability performance.

[0054] The edge cover layer 5 made of a conductive rubber composition, in which the radially innermost ply 3a among at least one ply 3 is provided, has a portion that contacts the carcass 2. Therefore, electric charge can pass through the carcass 2 via the edge cover layer 5, and thus it is possible to improve the conductivity of the tire 1.

[0055] Since the axial distance L is at least 10.0 mm or more greater than the axial distance Le, it is possible to improve the conductivity of the tire 1.

[0056] When this axial distance L is greater than the axial distance Le by less than 10.0 mm, there is a risk that the contact between the edge cover layer 5 and the carcass 2 will be insufficient to form a sufficient conductive path.

[0057] This distance L is preferably at least 11.0 mm or more greater than the axial distance Le, more preferably at least 12.0 mm or more greater than the axial distance Le, and even more preferably at least 15.0 mm or more greater than the axial distance Le.

[0058] Since the axial distance Le is equal to at most 15.0 mm, it is possible to improve the manufacturing efficiency of the tire 1.

[0059] When this axial distance Le is greater than 15.0 mm, there is a risk that the total width of the semi-finished product of the side wall 6 becomes too large and the manufacturing efficiency decreases.

[0060] This axial distance Le is preferably at most equal to 13.0 mm, more preferably at most equal to 12.0 mm, and still more preferably at most equal to 10.0 mm.

[0061] Since the edge cover layer 5 further covers the axially outermost surface and the radially outermost surface of the radially innermost ply 3a among at least one ply 3 up to or less than the range of the axial distance L measured from the axial end of the radially innermost ply 3a among at least one ply 3, the edge cover layer 5 covering the axially outermost surface and the radially outermost surface can prevent not only the peeling between the ply 3 and the carcass 2 but also the peeling between the plies 3, so that the durability performance can be improved.

[0062] Since the volume resistivity of the conductive rubber composition constituting the edge cover layer 5 is at most equal to 5.00×10 5 Ω·cm, it is possible to improve the conductivity of the tire 1.

[0063] When the volume resistivity of the conductive rubber composition is greater than 5.00×10 5 Ω·cm, there is a risk that the edge cover layer 5 cannot function efficiently as a conductive path to the carcass 2.

[0064] This volume resistivity of the conductive rubber composition constituting the edge cover layer 5 is preferably at most equal to 4.00×10 5 Ω·cm, more preferably at most equal to 3.75×10 5 Ω·cm.

[0065] The tire 21 according to the second embodiment of the present invention will be described with reference to FIG. 3. FIG. 3 is an enlarged schematic view of the tire according to the second embodiment of the present invention, corresponding to the portion denoted by II in FIG. 1. Since the configuration of this second embodiment is the same as that of the first embodiment except for the arrangement shown in FIG. 3, it will be described with reference to FIG. 3.

[0066] As shown in FIG. 3, the tire 21 has a tread 24 intended to contact the ground via a contact surface 241 during rotation, and a pair of sidewalls 26 (only one is shown in FIG. 1) extending from each of the two axial ends of the tread 24. The tire 21 includes at least one ply 23 disposed radially inside the tread 24, and the at least one ply 23 includes a plurality of parallel reinforcing elements (not shown) extending at an angle A (not shown) with respect to the circumferential direction of the tire. When applied to a passenger car tire, this angle A is often greater than 10 degrees and less than 45 degrees. In the present embodiment, the tire 21 includes two plies 23a and 23b, and the angle A is 27 degrees.

[0067] As shown in FIG. 3, the tire 21 further includes a carcass 22 disposed radially inside the at least one ply 23.

[0068] As shown in FIG. 3, at least the innermost ply 23a in the at least one ply 23 is made of a conductive rubber composition, covers at least the radially inner surface of the innermost ply 23a in the at least one ply 23, and an edge cover layer 25 is provided that extends up to an axial distance L measured from the axial end of the innermost ply 3a in the at least one ply 23. At least one of the sidewalls 6, together with the carcass 22, extends downwards directly under the innermost ply 23a in the at least one ply 23 up to an axial distance Le measured from the axial end of the innermost ply 23a in the at least one ply 23. The axial distance L is greater than the axial distance Le. The axial distance L is at least 10.0 mm greater than the axial distance Le. The axial distance Le is equal to 15.0 mm at most.

[0069] As shown in FIG. 3, at least two radially adjacent plies 23a, 23b are provided in the tire 21, and an edge cover layer 25 covering the edge portions of each of the at least two plies 23 is provided. The tire 21 further includes at least one conductive path (not shown) that opens to the contact surface 241.

[0070] As shown in FIG. 3, one edge cover layer 25 of the radially adjacent plies 23a, 23b has a portion that contacts the other edge cover layer 25 of the radially adjacent plies 23a, 23b.

[0071] Since at least two radially adjacent plies 23a, 23b are provided in the tire 21, and an edge cover layer 25 covering the edge portions of the plies 23a, 23b is provided for each of all of the at least two plies 23, the edge cover layer 25 covering the edge portion of each of the at least two plies 23 can prevent not only the separation between the ply 23 and the carcass 22 but also the separation between the plies 23, so that the durability performance can be improved.

[0072] Since one edge cover layer 25 of the plies 23 adjacent in the radial direction has a portion that contacts the other edge cover layer 25 of the adjacent ply in the radial direction, the edge cover layer 25 covering the edge portion of each of the plies 23 adjacent in the radial direction can prevent not only the separation between the ply 23 and the carcass 22 but also the separation between the plies 23, and at the same time can reinforce the conductive path to the carcass 22, so that it is possible to improve the durability performance and conductivity at the same time.

[0073] Since the tire 21 further includes at least one conductive path that opens to the contact surface 241, the charge can move to the ground through at least one conductive path that opens to the contact surface 241, so that the conductivity of the tire 21 can be further improved.

[0074] The structure of at least one conductive path opening to the contact surface 241 can be in any form known to those skilled in the art. The rubber composition constituting at least one conductive path opening to the contact surface 241 can be made using the same rubber composition as that constituting the edge cover layer 25. At least one conductive path opening to the contact surface 241 can extend beyond the radially innermost part of the tread 24.

[0075] The present invention is not limited to the described and illustrated examples, and various changes can be made without departing from its framework.

[0076] FIG. 4 is an enlarged schematic view of a prior-art tire corresponding to the part denoted II in FIG. 1. In this FIG. 4, the tire 101 has a tread 104 intended to contact the ground via a contact surface 1041 during rotation, and a pair of sidewalls 106 extending from each of the two axial ends of the tread 104. The tire 101 includes at least one ply 103 (two plies 103a and 103b in this prior art) disposed radially inside the tread 104. The at least one ply 103 includes a plurality of parallel reinforcing elements (not shown) extending at an angle A with respect to the circumferential direction of the tire, where the angle A is greater than 10 degrees. The tire 101 further includes a carcass 102 disposed radially inside the at least one ply 103. In at least the radially innermost ply 103a among the at least one ply 23, an edge cover layer 105 made of a conductive rubber composition is provided to at least cover the radially inner surface of the radially innermost ply 103a among the at least one ply 103. At least one of the sidewalls 106 extends together with the carcass 102 downward toward directly below the radially innermost ply among the at least one ply 103. The edge cover layer 5 provided in the radially innermost ply among the at least one ply 103 has no portion in contact with the carcass 102. The radially outermost ply 103b among the at least one ply 103 is not provided with an edge cover layer.

[0077] To confirm the effects of the present invention, two types of tires (Examples) to which the present invention is applied and another type of tire (Reference) were prepared.

[0078] Example 1 was the tire described in the above-described first embodiment. Example 2 was also the tire described in the above-described first embodiment, and was a tire manufactured using a low hysteresis loss composition for the calendering mixture of the belt (ply). Reference 1 was a tire according to the prior art, and had basically the same structure as Example 1, but the edge cover layer provided with the radially innermost ply had no portion in contact with the carcass. Reference 2 was also a tire according to the prior art, and was a tire manufactured using a low hysteresis loss composition for the calendering mixture of the belt (ply). All Examples and References were manufactured using the same rubber-based materials as typical rubber-based materials used for passenger car tires, except as noted. The tire dimensions of both the Examples and the References were 245 / 45R18, mounted on an 8.0J×18 conductive rim, and inflated to 200 kPa.

[0079] Conductivity Test

[0080] The electrical resistance of the tire was measured in accordance with WdK110 by placing the test tire and rim assembly on a steel plate, applying a load of 595 kg to the tire, then passing a current of 1,000 V between the rim and the steel plate, and reading the electrical resistance with a high resistance meter.

[0081] The results are shown in Table 1. In this Table 1, the results are represented by "X" meaning exceeding the threshold value of 108 Ω, "G" meaning 108 Ω or less, and "V" meaning 107 Ω or less.

[0082] [Table 1] TIFF2025520952000002.tif17153

[0083] As can be seen from Table 1, this example shows an improvement in conductivity represented by electrical resistance while improving manufacturing efficiency by reducing the number of semi-finished products, which cannot be achieved with the tires disclosed in the prior art.

Explanation of Signs

[0084] 1, 2 Tire 2, 22 Carcass 3, 23 Ply 3a Radially innermost ply 3b Adjacent ply 4, 24 Tread 41, 241 Contact surface 5, 25 Edge cover layer 6, 26 Sidewall L Distance that the edge cover layer extends axially from the axial end of the radially innermost ply Le Distance that the sidewall extends axially from the axial end of the radially innermost ply

Claims

1. A tire (1) having a tread (4) intended to contact the ground via a contact surface (41) when rotating, and a pair of sidewalls (6) extending from each of the two axial ends of the tread (4), The tire (1) comprises at least one ply (3) positioned radially inward of the tread (4), the at least one ply (3) comprising a plurality of parallel reinforcing elements extending at an angle A with respect to the circumferential direction of the tire, the angle A being greater than 10 degrees, and the tire (1) further comprises a carcass (2) positioned radially inward of the at least one ply (3), the at least radially innermost ply of the at least one ply (3) comprising a conductive rubber composition that at least covers the radially inner surface of the radially innermost ply of the at least one ply (3) An edge cover layer (5) is provided within the carcass (2) that extends to an axial distance L measured from the axial end of the radially innermost ply, and at least one of the sidewalls (6) together with the carcass (2) extends directly below the radially innermost ply within the at least one ply (3) to an axial distance Le measured from the axial end of the radially innermost ply within the at least one ply (3), the axial distance L being greater than the axial distance Le, and the edge cover layer (5) on which the radially innermost ply within the at least one ply (3) is provided has a portion that contacts the carcass (2). A tire (1) characterized in that the axial distance L is at least 10.0 mm greater than the axial distance Le.

2. The tire (1) according to claim 1, wherein the axial distance Le is equal to a maximum of 15.0 mm.

3. The tire (1) according to claim 1 or 2, wherein the edge cover layer (5) further covers the outermost axial surface and the outermost radial surface of the innermost radial ply among the at least one ply (3) to a range of or less of the axial distance L measured from the axial end of the innermost radial ply among the at least one ply (3).

4. The tire (1) according to claim 1, wherein the tire (1) is provided with at least two radially adjacent plies, and each of the at least two plies (3) is provided with the edge cover layer (5) that covers the edge portion of each ply (3).

5. The tire (1) according to claim 4, wherein the edge cover layer (5) of one of the radially adjacent plies (3) has a portion that contacts the other edge cover layer (5) of the radially adjacent ply (3).

6. The volume resistivity of the conductive rubber composition constituting the edge cover layer (5) is a maximum of 5.00 × 10⁻¹⁰. 5 A tire (1) according to claim 1, which is equal to Ω·cm.

7. The tire (1) according to claim 1, further comprising at least one conductive path opening into the contact surface (41).

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