Pneumatic tire

Abstract

To provide a pneumatic tire configured so that a user can easily find a scratch of a surface of a side wall, and subsequently can take proper measures such as preventing the tire from going flat.SOLUTION: The pneumatic tire comprises a pair of beads 10, a pair of side walls 20 extending from the pair of beads 10 to outside in a tire radial direction and including tire maximum width positions 20W, and a tread 30 arranged between the pair of side walls 20. The side walls 20 include non-woven fabric sheets 25 embedded inside the side walls 20 so as to include the tire maximum width positions 20W. The non-woven fabric sheets 25 include non-woven fabrics, where the non-woven fabrics have a color different from a color of outer surfaces 20a of the side walls 20.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pneumatic tire to be mounted on a vehicle. [Background technology]

[0002] The sidewall constituting the outer surface of this type of pneumatic tire is a part that is easily damaged by contact with curbs, etc. Therefore, it is preferable that the sidewall has a suitable strength, hardness, etc., but on the other hand, there is a limit to how much strength the sidewall can have because it deteriorates the ride comfort. Patent Document 1 discloses a pneumatic tire in which a nonwoven fabric-rubber composite, in which a nonwoven fabric is covered with rubber, is embedded in the sidewall as a side reinforcing layer that reinforces the sidewall. [Prior art documents] [Patent documents]

[0003] [Patent Document 2] JP 2015-93574 A Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, tires are black on both the outside and inside. Therefore, if the outside surface of the sidewall is damaged, it is difficult to notice the damage or to easily determine the depth of the damage. As a result, leaving the damage unattended can lead to a flat tire.

[0005] Therefore, an object of the present invention is to provide a pneumatic tire that allows a driver to easily notice that a sidewall has been damaged, thereby enabling appropriate measures to be taken, such as preventing a puncture from occurring. [Means for solving the problem]

[0006] The pneumatic tire of the present invention is a pneumatic tire including beads, sidewalls extending radially outward from a pair of the beads and including a maximum tire width position, and a tread disposed between the pair of sidewalls, wherein the sidewalls include a nonwoven fabric sheet embedded inside the sidewalls so as to include the maximum tire width position, the nonwoven fabric sheet including a nonwoven fabric, and the nonwoven fabric having a color different from the color of the outer surface of the sidewalls. Effect of the Invention

[0007] According to the present invention, a pneumatic tire can be provided in which external damage to the sidewall can be easily noticed, and as a result, appropriate measures can be taken to prevent punctures from occurring. [Brief description of the drawings]

[0008] [Figure 1] 1 is a half cross-sectional view in an axial direction of a pneumatic tire according to an embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to Fig. 1. Fig. 1 shows a cross section in the tire axial direction of a tire 1, which is a pneumatic tire for a vehicle according to the embodiment. The tire 1 is a tire for a passenger car. Note that the configuration of the tire 1 of the embodiment can also be applied to tires for various vehicles such as light trucks, trucks, and buses.

[0010] The cross-sectional view of FIG. 1 is a cross-sectional view of a tire 1 mounted on a standard rim (not shown) and inflated to a standard internal pressure in an unloaded state. The standard rim is a rim that is determined for each tire by a standard system including the standard on which the tire is based, for example, a standard rim for JATMA, and a "Measuring Rim" for TRA and ETRTO. The standard internal pressure is an air pressure determined for each tire by each standard in a standard system including the standard on which the tire is based, and in the case of tires for trucks and buses and tires for light trucks, it is the maximum air pressure for JATMA, the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" for TRA, and "INFLATION PRESSURE" for ETRTO. For tires for passenger cars, it is usually 180 kPa, but for tires marked "Extra Load" or "Reinforced", it is 220 kPa.

[0011] The basic structure of the tire 1 is symmetrical in a cross section in the tire axial direction. Fig. 1 shows a cross section of the right half of the tire 1, and the left half (not shown) has the same structure. In Fig. 1, the symbol S1 indicates the tire equatorial plane. The tire equatorial plane S1 is a plane perpendicular to the tire rotation axis and located at the center in the tire axial direction.

[0012] Here, the tire axial direction is a direction parallel to the tire rotation axis, and is the left-right direction on the paper in Fig. 1. In Fig. 1, this is illustrated as the tire axial direction X. The tire axially inner side is a direction approaching the tire equatorial plane S1, and is the left side on the paper in Fig. 1. The tire axially outer side is a direction away from the tire equatorial plane S1, and is the right side on the paper in Fig. 1.

[0013] The tire radial direction is a direction perpendicular to the tire rotation axis, and is the up-down direction on the paper in Fig. 1. In Fig. 1, this is illustrated as tire radial direction Y. The outer side in the tire radial direction is a direction away from the tire rotation axis, and is the upper side on the paper in Fig. 1. The inner side in the tire radial direction is a direction approaching the tire rotation axis, and is the lower side on the paper in Fig. 1.

[0014] As shown in FIG. 1, the tire 1 includes a pair of beads 10, a pair of sidewalls 20 extending radially outward from each of the pair of beads 10, a tread 30 disposed between the pair of sidewalls 20, a shoulder 40 which is a transition portion from the sidewalls 20 to the tread 30, a carcass ply 50 disposed spanning between the pair of beads 10, and an inner liner 60 disposed on the tire cavity side of the carcass ply 50.

[0015] The pair of beads 10 are disposed on both axial sides of the tire and on the inner ends in the tire radial direction. The bead 10 has a bead core 11, a bead filler 12 extending from the bead core 11 to the outer side in the tire radial direction, a chafer 13, and a rim strip rubber 14.

[0016] The bead core 11 is an annular member in which a rubber-coated metal bead wire is wound multiple times in the tire circumferential direction. The bead core 11 is a member that serves to fix the tire 1 filled with air to the rim. The bead filler 12 has a tapered shape that decreases in thickness as it extends from the tire radial inner side to the tire radial outer side. The bead filler 12 is provided to increase the rigidity of the peripheral portion of the bead 10 and ensure high maneuverability and stability. The bead filler 12 is made of, for example, rubber that is harder than the surrounding rubber members. The bead filler 12 is joined to the tire radial outer surface of the bead core 11.

[0017] The chafer 13 is provided in a manner to further surround the outside of the carcass ply 50 which surrounds the bead core 11 and the bead filler 12 .

[0018] The rim strip rubber 14 is disposed on the axially outer side of a part of the carcass ply 50 and the chafer 13, and further extends to the vicinity of the radially inner side of the chafer 13. The rim strip rubber 14 has a rim line 14c that protrudes axially outward of the tire. The rim line 14c is a circular line that runs along the tire circumferential direction. The rim line 14c is a mark for matching the edge of the rim. When the edge of the rim is matched with the rim line 14c over the entire circumference, the tire 1 is determined to be correctly mounted on the rim. The rim strip rubber 14 including the rim line 14c forms a rim protector 15 that is disposed to protrude axially outward from the rim.

[0019] The sidewall 20 includes a nonwoven fabric sheet 25 disposed axially outboard of the carcass ply 50 and embedded within the sidewall 20, and a sidewall rubber 21 disposed axially outboard of the nonwoven fabric sheet 25.

[0020] The nonwoven fabric sheet 25 is disposed in a region extending from the shoulder 40 to the axially outer portion of the rim strip rubber 14. Since the nonwoven fabric sheet 25 is a characteristic feature of the present disclosure, details thereof will be described later.

[0021] The sidewall rubber 21 is a rubber that constitutes the outer surface of the tire 1. The sidewall rubber 21 is the portion that bends the most when the tire 1 performs its cushioning function, and typically, flexible rubber having fatigue resistance is used for the sidewall rubber 21.

[0022] The sidewall rubber 21 is disposed in a region extending from the shoulder 40 to the radially outer portion of the bead 10 in the tire radial direction. An outer end 21a of the sidewall rubber 21 in the tire radial direction covers an axially outer end 37a of a tread rubber 37 of a tread 30 described later. An inner end 21b of the sidewall rubber 21 in the tire radial direction extends to the vicinity of the rim line 14c. An outer surface 20a of the sidewall 20 includes a maximum tire width position 20W.

[0023] The tread 30 includes an endless belt 31, a cap ply 34, and a tread rubber 37. The belt 31 is disposed on the outer side of the carcass ply 50 in the tire radial direction. The cap ply 34 is disposed on the outer side of the belt 31 in the tire radial direction. The tread rubber 37 is disposed on the outer side of the cap ply 34 in the tire radial direction.

[0024] The belt 31 is a member that reinforces the tread 30. The belt 31 of the embodiment has a two-layer structure including an inner belt 32 arranged on the outer side of the inner liner 60 in the tire radial direction, and an outer belt 33 arranged on the outer side of the inner belt 32 in the tire radial direction. Both the inner belt 32 and the outer belt 33 have a structure in which a plurality of belt cords such as steel cords are covered with rubber. The inner belt 32 is wider than the outer belt 33. By providing the belt 31, the rigidity of the tire 1 is ensured, and the contact of the tread 30 with the road surface is improved. Note that the belt 31 is not limited to a two-layer structure, and may have a single layer structure, or a three-layer structure or more.

[0025] The cap ply 34 is a member that reinforces the tread 30 together with the belt 31. The cap ply 34 of the embodiment has a cap ply body 35 that is wider than the belt 31 and covers the entire belt 31 from the tire outer surface side, and an edge ply 36 that covers only the end portion of the belt 31 on the outer side in the tire axial direction. The edge ply 36 is disposed on the tire radial inner side of the cap ply body 35. Both the cap ply body 35 and the edge ply 36 have a structure in which a plurality of insulating organic fiber cords such as polyamide fiber are covered with rubber. By providing the cap ply 34, it is possible to improve the durability of the tire 1 and reduce road noise during driving. The cap ply body 35 is not limited to a single-layer structure as in the embodiment, but may have a two-layer structure or a three-layer structure or more.

[0026] The tread rubber 37 is disposed on the outer side of the cap ply 34 in the tire radial direction. The tread rubber 37 forms a tread surface 38, which is the outer surface of the tread 30 and comes into contact with the road surface. A plurality of main grooves 38a (only one of which is visible in FIG. 1 ) extending along the tire circumferential direction are formed in the tread surface 38 at intervals in the tire axial direction. An axially outer end 37a of the tread rubber 37 protrudes axially outward beyond the axially outer end of the cap ply 34 and is bent inward in the tire radial direction. The axially outer end 37a of the tread rubber 37 is covered by the radially outer end 21a of the sidewall rubber 21.

[0027] The shoulder 40 is a region where the tread 30 transitions to the sidewall 20. The shoulder 40 includes a region where an end 21a of the sidewall rubber 21 on the outer side in the tire radial direction covers an end 37a of the tread rubber 37 on the outer side in the tire axial direction.

[0028] A rubber pad 39 is disposed inside the tire near the area extending from the tread 30 to the shoulder 40. This rubber pad 39 is disposed between the nonwoven fabric sheet 25 and the tread rubber 37, between the carcass ply 50 and the tread rubber 37, and between the carcass ply 50 and the belt 31, from the shoulder 40 to the tread 30.

[0029] The carcass ply 50 is laid between a pair of beads 10. The carcass ply 50 is embedded inside the tire 1 in a manner that the carcass ply 50 passes between the pair of beads 10, through a pair of sidewalls 20, a pair of shoulders 40, and the tire cavity side of the tread 30. In the tread 30, a belt 31 is disposed on the outer side of the carcass ply 50 in the tire radial direction.

[0030] The carcass ply 50 includes a plurality of ply cords (not shown) that form the framework of the tire 1. The plurality of ply cords extend, for example, along a plane along the tire axial direction, and are arranged side by side in the tire circumferential direction. The ply cords are made of insulating organic fiber cords such as polyester or polyamide. The carcass ply 50 is formed by covering the plurality of ply cords with rubber.

[0031] The carcass ply 50 includes a ply main body 50A and a pair of turned-up portions 50B. The ply main body 50A is a portion that extends from the tread 30 through a pair of shoulders 40 and a pair of sidewalls 20 toward the axially inner side of each of the pair of beads 10. The pair of turned-up portions 50B are portions that are folded back toward the radially outer side of the tire by being wound from the ply main body 50A around each of the pair of bead cores 11, and extend along the sidewalls 20.

[0032] The ply body portion 50A is disposed on the tread 30 on the inner side in the tire radial direction of the belt 31, and on the sidewall 20 on the inner side in the tire axial direction of the nonwoven fabric sheet 25.

[0033] The carcass ply 50 of the embodiment has a two-layer structure in which a first carcass ply 51 and a second carcass ply 52 are overlapped. In the ply body portion 50A, the first carcass ply 51 is disposed on the tire inner cavity side of the second carcass ply 52. ​​In the turned-up portion 50B, the first carcass ply 51 is disposed on the tire axially outer side of the second carcass ply 52. ​​The first carcass ply 51 of the turned-up portion 50B extends to the tire radial center of the bead filler 12. The second carcass ply 52 of the turned-up portion 50B extends to the tire radial center of the sidewall 20 through the tire maximum width position 20W. The portion of the turned-up portion 50B that is radially outer than the bead filler 12 is overlapped on the tire axially outer side of the ply body portion 50A.

[0034] The chafer 13 of the bead 10 described above surrounds the end of the carcass ply 50 on the inner side in the tire radial direction, the end winding around the bead core 11 .

[0035] Although the carcass ply 50 in the embodiment has a two-layer structure, the carcass ply 50 may have one layer or three or more layers. When the carcass ply 50 has a two-layer or more layer structure, it is preferable because the tire 1 is sufficiently prevented from locally deforming near the mounting portion of the rim.

[0036] The inner liner 60 covers the inner surface of the ply body portion 50A of the carcass ply 50 and the axially inner portion of the chafer 13 between the pair of beads 10 to form the tire cavity surface. The inner liner 60 of the embodiment has a two-layer structure in which a first inner liner 61 and a second inner liner 62 are overlapped. The first inner liner 61 is disposed on the tire cavity side of the second inner liner 62. The first inner liner 61 and the second inner liner 62 are made of air-permeable resistant rubber and prevent air in the tire cavity from leaking to the outside.

[0037] The tire 1 of the embodiment is provided with a reinforcing rubber layer 65 extending from the shoulder 40 to the radially outer portion of the sidewall 20. The reinforcing rubber layer 65 is sandwiched between the second inner liner 62 and the ply main body portion 50A of the carcass ply 50.

[0038] Here, the rubber used for the bead filler 12 has a hardness higher than at least the sidewall rubber 21 and the inner liner 60. The hardness of the rubber is a hardness tested according to "JIS K6253-3:2012 durometer hardness type A".

[0039] For example, when the hardness of the sidewall rubber 21 is used as a standard, the hardness of the bead filler 12 is preferably about 1.2 to 2.3 times the hardness of the sidewall rubber 21. By setting the hardness at such a level, it is possible to ensure a balance between the flexibility of the tire and the rigidity in the vicinity of the bead 10.

[0040] Next, the nonwoven fabric sheet 25 embedded in the sidewall 20 will be described. The nonwoven fabric sheet 25 is embedded in the sidewall 20 in a region extending from the shoulder 40 to the axially outer portion of the rim strip rubber 14. The nonwoven fabric sheet 25 is embedded in a region including the tire maximum width position 20W. In other words, the sidewall 20 includes the nonwoven fabric sheet 25 embedded therein so as to include the tire maximum width position 20W.

[0041] A large portion of the nonwoven fabric sheet 25 is sandwiched between the carcass ply 50 and the sidewall rubber 21. A large portion of the inner surface of the nonwoven fabric sheet 25, which faces the tire cavity, contacts the axially outer surface of the carcass ply 50. An inner surface of an end 25b of the nonwoven fabric sheet 25 on the inner side in the tire radial direction contacts a portion of the rim strip rubber 14 that is more outer in the tire radial direction than the rim line 14c. The end 25b of the nonwoven fabric sheet 25 on the inner side in the tire radial direction overlaps the bead filler 12 in the tire axial direction.

[0042] A large portion of the outer surface of the nonwoven fabric sheet 25, which is the surface facing the outer surface of the tire, contacts the axially inner surface of the sidewall rubber 21. The outer surface of an end 25a of the nonwoven fabric sheet 25 on the outer side in the tire radial direction contacts the inner surface of the rubber pad 39. A thick width portion 26 where the thickness of the nonwoven fabric sheet 25 is maximum is formed at the end of the nonwoven fabric sheet 25 on the outer side in the tire radial direction in the region of the nonwoven fabric sheet 25 that contacts the sidewall rubber 21. This thick width portion 26 has a protruding portion 26a that protrudes axially outward and bites into the sidewall rubber 21.

[0043] The nonwoven fabric sheet 25 includes a nonwoven fabric. The nonwoven fabric sheet 25 may be a nonwoven fabric alone, or may be a nonwoven fabric with rubber attached thereto. In the case of a nonwoven fabric with rubber attached thereto, the nonwoven fabric may be impregnated with rubber, or the nonwoven fabric may be covered with a topping rubber. Furthermore, the nonwoven fabric impregnated with rubber may be covered with a topping rubber.

[0044] The nonwoven fabric is, for example, a felt-like sheet, and the fibers constituting the nonwoven fabric are not oriented, but are randomly oriented. A nonwoven fabric having randomly oriented fibers is preferable because it has a higher strength sheet with fewer gaps between the fibers than one having an orientation. The thickness of the sidewall 20, including the nonwoven fabric sheet 25, is determined according to the design.

[0045] Examples of materials for the nonwoven fabric include, but are not limited to, organic fibers such as polyester fibers, aliphatic polyamide fibers (nylon fibers), aromatic polyamide fibers (aramid fibers), polyvinyl alcohol fibers, and carbon fibers, and inorganic fibers such as metal fibers and glass fibers. From the viewpoint of weight reduction, nonwoven fabrics made of organic fibers are preferred, and among organic fibers, polyester fibers are preferred from the viewpoints of cost reduction and strength.

[0046] The sheet-like nonwoven fabric is produced by a conventionally known production method. For example, methods for forming fibers into a sheet include a dry method, a wet method, a spunbond method, a meltblowing method, an airlaid method, etc., and methods for bonding fibers include, but are not limited to, a chemical bond method, a thermal bond method, a needle punch method, a hydroentanglement method, etc.

[0047] When the nonwoven fabric sheet 25 has a structure in which rubber is attached to a nonwoven fabric, the type of rubber is not limited, but rubber used in tires is suitable, and in particular, if the rubber is the same type as the sidewall rubber 21, it has a high affinity with the sidewall rubber 21, and is preferable in that, for example, the nonwoven fabric sheet 25 is less likely to peel off from the sidewall rubber 21. Alternatively, rubber with a higher hardness than the sidewall rubber 21 is preferable because it provides resistance to external damage. When the rubber contained in the nonwoven fabric sheet 25 is the same type as the sidewall rubber 21, the two may be integrated after the vulcanization process.

[0048] The nonwoven fabric constituting the nonwoven fabric sheet 25 has a color different from the color of the outer surface 20a of the sidewall 20, i.e., a color different from the color of the sidewall rubber 21 constituting the outer surface. The tire 1 including the sidewall 20 is entirely black, similar to a typical tire. Therefore, the nonwoven fabric of the nonwoven fabric sheet 25 is a color other than black.

[0049] The color of the nonwoven fabric of the nonwoven fabric sheet 25 is not limited as long as it is a color other than black and different from the outer surface 20a of the sidewall 20. However, a color that is visually clearly different from black and has a clear contrast with the sidewall 20 is preferable, for example, a chromatic color or a fluorescent color. A chromatic color is a color that has a hue such as blue, red, or yellow, and is a color other than a color that has no hue such as white, black, and gray located on a gradation between them. A fluorescent color is a color that emits a clear and bright color and is also called a neon color. By coloring the nonwoven fabric in such a color, the nonwoven fabric of the embodiment can be obtained.

[0050] The nonwoven fabric can be colored, for example, by immersing the nonwoven fabric in a coloring material such as a dye or paint, or by spraying such a coloring material onto the nonwoven fabric.

[0051] The color of the nonwoven fabric of the nonwoven fabric sheet 25 may be white to provide a clear contrast with black. However, because white is easily soiled, and from the viewpoint of improving recognizability, it is more preferable to use the above-mentioned chromatic or fluorescent colors as the notification color for notifying that the sidewall has been damaged.

[0052] When the tire 1 (raw tire) is molded before vulcanization, the nonwoven fabric sheet 25 is attached to the axially outer surface of the carcass ply 50 after wrapping the wound-up portion 50B of the carcass ply 50 around the bead core 11 and the bead filler 12 and arranging the rim strip rubber 14 as a part of the bead 10. Thereafter, the tread 30 and the sidewall rubber 21 are arranged and the process is transferred to the vulcanization step.

[0053] When the nonwoven fabric sheet 25 contains rubber, the rubber may be raw rubber before vulcanization or may be vulcanized rubber. When the rubber contained in the nonwoven fabric sheet 25 is raw rubber, the nonwoven fabric sheet 25 can be attached to the carcass ply 50 as it is. When the rubber contained in the nonwoven fabric sheet 25 is vulcanized, the nonwoven fabric sheet 25 is attached to the carcass ply 50 using, for example, an adhesive tape or a vulcanization adhesive. By vulcanizing the entire raw tire on which the nonwoven fabric sheet 25 is disposed in this manner, the nonwoven fabric sheet 25 is embedded as part of the sidewall 20.

[0054] When the tire 1 according to the embodiment in which the nonwoven fabric sheet 25 is embedded in the sidewall 20 as described above is mounted on a vehicle and the vehicle is traveling, the tire 1 may receive external damage to the outer surface 20a of the sidewall 20 when the sidewall 20 comes into contact with a curb, for example. When the sidewall 20 is damaged and the sidewall rubber 21 is scraped off, and the damage reaches the nonwoven fabric of the nonwoven fabric sheet 25, the nonwoven fabric is exposed on the outer surface 20a of the sidewall 20.

[0055] Since the nonwoven fabric has a different color from the outer surface 20a of the sidewall 20, the color of the nonwoven fabric appears in the damaged portion of the sidewall 20. Even if the depth of the damage is relatively shallow and cannot be noticed by visual inspection, the vehicle user can easily notice that the sidewall 20 has been damaged by recognizing the color of the nonwoven fabric. By checking the damaged portion, the depth of the damage can be known and leaving the damage unattended can be avoided. If the damage is deep enough to cause a puncture, the puncture can be avoided by repairing or replacing the tire. To repair the damage, for example, a method of applying rubber to the outer surface 20a of the sidewall 20 and covering the nonwoven fabric sheet 25 can be mentioned. As described above, according to the tire 1 of the embodiment, when the sidewall 20 is damaged, appropriate measures such as preventing a puncture can be taken.

[0056] Since the nonwoven fabric constituting the nonwoven fabric sheet 25 has high strength, the sidewall 20 has improved resistance to external damage compared to a sidewall without the nonwoven fabric sheet 25. In the embodiment, the nonwoven fabric sheet 25 is disposed so as to include the tire maximum width position 20W, which is the part of the sidewall 20 that is most susceptible to external damage, and therefore this improvement in resistance to external damage is effective, making it possible to keep external damage to a minor level.

[0057] The outer surface 20a of the sidewall 20 may be provided with a mark or the like using a protrusion. Such marks include, for example, a manufacturer, a brand, a tire size, and the like. In the tire 1 of the embodiment, the nonwoven fabric sheet 25 is embedded in the sidewall 20. Therefore, the nonwoven fabric sheet 25 does not affect the mark or the like provided on the outer surface 20a of the sidewall 20.

[0058] Here, the thickness of the nonwoven fabric sheet 25 is not limited, but is preferably thin enough not to affect the characteristics of the sidewall 20, and is preferably, for example, 0.3 mm to 0.5 mm after vulcanization.

[0059] The distance from the nonwoven fabric sheet 25 to the outer surface 20a of the sidewall 20 (the thickness of the sidewall rubber 21 from the nonwoven fabric sheet 25 to the outer surface 20a) is preferably, for example, 0.5 mm or more and 1 mm or less. If it is less than 0.5 mm, the nonwoven fabric may be exposed even in the event of minor damage that does not affect tire performance, which may impair the appearance. On the other hand, if it exceeds 1 mm, even if damage that affects tire performance occurs, the damage may not reach the nonwoven fabric of the nonwoven fabric sheet 25, and it may be difficult to recognize the damage by visually inspecting the nonwoven fabric exposed by the damage.

[0060] The tire 1 according to the embodiment described above provides the following advantages.

[0061] (1) A tire 1 according to the embodiment includes beads 10, sidewalls 20 extending radially outward from the pair of beads 10 and including a tire maximum width position 20W, and a tread 30 disposed between the pair of sidewalls 20, wherein the sidewalls 20 include a nonwoven fabric sheet 25 embedded inside the sidewalls 20 so as to include the tire maximum width position 20W, the nonwoven fabric sheet 25 including a nonwoven fabric, and the nonwoven fabric has a color different from the color of an outer surface 20a of the sidewalls 20.

[0062] This allows the user of the tire 1 to easily notice that the sidewall 20 has been damaged, and to take appropriate measures such as preventing a puncture. The nonwoven fabric sheet 25 improves the damage resistance of the sidewall 20.

[0063] (2) In the tire 1 according to the above embodiment (1), the color of the nonwoven fabric of the nonwoven fabric sheet 25 is preferably either a chromatic color or a fluorescent color.

[0064] This allows the user of the tire 1 to easily notice that the sidewall 20 has been damaged, and to take appropriate measures such as preventing a puncture from occurring.

[0065] (3) In the tire 1 according to the above embodiments (1) and (2), the thickness of the nonwoven fabric sheet 25 is preferably 0.3 mm or more and 0.5 mm or less.

[0066] This suppresses the increase in mass due to the nonwoven fabric sheet 25 and suppresses the deterioration of the rolling resistance, and by ensuring a minimum thickness of the nonwoven fabric sheet 25, it is easy to avoid a situation in which the nonwoven fabric is lost when an injury occurs, making it difficult to know that the injury has occurred.

[0067] (4) In the tire 1 according to the embodiment described above in (1) to (3), the distance from the nonwoven fabric sheet 25 to the outer surface 20a of the sidewall 20 is preferably 0.5 mm or more and 1 mm or less.

[0068] This prevents the nonwoven fabric from being exposed in the case of minor damage, ensuring a good appearance, and in the case of damage that affects tire performance, the damage causes the nonwoven fabric to be exposed on the outer surface 20a of the sidewall 20, making it possible to reliably recognize the damage visually.

[0069] Although specific embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and even if modifications and improvements are made within the scope of the present invention, they will still be included in the scope of the present invention.

[0070] For example, in the above embodiment, the nonwoven fabric sheet 25 is in contact with the carcass ply 50, but the sidewall rubber 21 is inserted between the nonwoven fabric sheet 25 and the carcass ply, and the nonwoven fabric sheet 25 is embedded in the sidewall rubber 21, and the entire nonwoven fabric sheet 25 may be covered with the sidewall rubber 21.

[0071] The nonwoven fabric sheet 25 may be in a form in which the nonwoven fabric is impregnated with rubber, and the impregnated rubber may be the sidewall rubber 21. That is, the nonwoven fabric may be impregnated with a portion of the sidewall rubber 21, and the nonwoven fabric and the sidewall rubber 21 may be integrated together. [Explanation of symbols]

[0072] 1...Tire (pneumatic tire) 10...Bead 20…Sidewall 20a…Outer surface of sidewall 20W…Tire maximum width position 25…Nonwoven sheet 30…Tread

Claims

1. Beads and a sidewall extending radially outward from the pair of beads and including a maximum tire width position; A pneumatic tire comprising: a tread disposed between a pair of the sidewalls, the sidewall includes a nonwoven fabric sheet embedded inside the sidewall so as to include the maximum tire width position, The nonwoven fabric sheet comprises a nonwoven fabric, the nonwoven fabric having a color different from a color of an outer surface of the sidewall.

2. The pneumatic tire according to claim 1 , wherein the nonwoven fabric has a color selected from the group consisting of a chromatic color and a fluorescent color.

3. The pneumatic tire according to claim 1 or 2, wherein the nonwoven fabric sheet has a thickness of 0.3 mm or more and 0.5 mm or less.

4. The pneumatic tire according to claim 1 or 2, wherein a distance from the nonwoven fabric sheet to an outer surface of the sidewall is equal to or greater than 0.5 mm and equal to or less than 1 mm.

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