Tire repair method, and tire

Abstract

To provide a tire repair method which can easily ensure good repair quality regardless of a skill of a worker, and a tire repaired to good quality regardless of a skill of a worker.SOLUTION: There is provided a tire repair method for repairing a crack K that is formed in a side rubber T01s located between a carcass ply and a tire surface in a tire side portion T01s of a tire and is terminated within the side rubber, comprising a staple step to fix the crack with staples S.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tire repair method and a tire. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there is a tire repair method for repairing cracks in the side portion of a tire using an adhesive (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2021124965A1 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional tire repair methods, there was a risk that the quality of the repair would vary depending on the skill of the worker.

[0005] An object of the present invention is to provide a tire repair method that can easily ensure good repair quality regardless of the skill of the worker, and a tire that has been repaired to good quality regardless of the skill of the worker. [Means for solving the problem]

[0006] [1] A tire repair method for repairing a crack that is formed in a side rubber located between a carcass ply and a tire surface in a tire side portion of a tire and that terminates within the side rubber, comprising: The tire repair method includes a stapling step of fixing the crack with staples. This makes it easier to ensure good repair quality regardless of the skill of the worker.

[0007] [2] The tire repair method described in [1], wherein the staple is made of a material harder than rubber. This allows the crack to be fixed more reliably.

[0008] [3] The tire repair method according to [1] or [2], wherein the staple is made of resin. In this case, the crack can be fixed and the repair effect can be easily maintained even during subsequent use.

[0009] [4] The tire repair method according to any one of [1] to [3], wherein the staple driving interval is 10 mm or less. This allows the crack to be fixed more reliably.

[0010] [5] The tire repair method according to any one of [1] to [4], further comprising an adhesive filling step of filling the cracks with adhesive. This allows the crack to be fixed more reliably.

[0011] [6] Each of the pair of legs of the staple is provided with a barb, or The surface of each of the pair of legs of the staple has an uneven portion having an uneven surface. The tire repair method according to any one of [1] to [5]. In this case, the staples become difficult to remove from the tire.

[0012] [7] The tire repair method according to any one of [1] to [6], further comprising an adhesive coating step of coating the surfaces of the pair of legs of the staple with an adhesive. In this case, the staples become difficult to remove from the tire.

[0013] [8] A tire, in which a crack formed in a side rubber located between a carcass ply and a tire surface in a tire side portion and terminating within the side rubber is fixed by a staple. This makes it possible to obtain a tire that has been repaired with good quality, regardless of the skill of the worker. Effect of the Invention

[0014] According to the present invention, it is possible to provide a tire repair method that can easily ensure good repair quality regardless of the skill of the worker, and a tire that has been repaired to good quality regardless of the skill of the worker. [Brief description of the drawings]

[0015] [Figure 1] 1 is a diagram illustrating a tire repair method according to a first embodiment of the present invention. [Diagram 2] 2 is a tire widthwise cross-sectional view that illustrates, in a tire widthwise direction, a schematic cross-section of a half portion of a tire according to one embodiment of the present invention that has been repaired by the tire repair method of FIG. 1. [Diagram 3] 5 is a diagram for explaining a tire repair method according to a second embodiment of the present invention. [Figure 4] 4 is a diagram for explaining an example in which the adhesive does not reach the depth of the crack in the tire repair method of FIG. 3. [Diagram 5] FIG. 2 is a schematic diagram illustrating a first modified example of the staple needle of FIG. 1. [Figure 6] FIG. 2 is a schematic diagram illustrating a second modified example of the staple needle of FIG. 1. [Figure 7] FIG. 2 is a schematic diagram illustrating a third modified example of the staple needle of FIG. 1. [Figure 8] 5 is a diagram for explaining a tire repair method according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] The tire repair method and tire according to the present invention can be suitably used for any type of pneumatic tire, for example, a heavy-duty pneumatic tire (for example, an off-the-road (construction vehicle) pneumatic tire, etc.).

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a tire repair method and a tire according to the present invention will be described with reference to the drawings. The same components and parts are designated by the same reference numerals in each drawing.

[0018] Fig. 1 is a drawing for explaining a tire repair method according to a first embodiment of the present invention. Fig. 1(a) shows a schematic view of a portion of a tire T01 near a crack K before repairing the tire T01 by the tire repair method according to the first embodiment, and Fig. 1(b) shows a schematic view of a portion of a tire T01 near a crack K after repairing the tire T01 by the tire repair method according to the first embodiment. Fig. 2 is a tire widthwise cross-sectional view showing a tire half portion of a tire T01 according to one embodiment of the present invention repaired by the tire repair method of Fig. 1 in a tire widthwise cross-sectional view. The tire repair method of each embodiment described in this specification is used to repair a crack K (FIGS. 1 and 2) that terminates in a side rubber T08 in a tire side portion T01s of a tire T01. The side rubber T08 is a rubber layer located between the carcass ply T05p and the tire surface T01f in the tire side portion T01s (FIG. 2). The crack K opens on the tire surface T01f. The crack K is, for example, a damaged portion such as a cut or crack. Since the crack K terminates in the side rubber T08, it does not reach the carcass ply T05p.

[0019] In this specification, as shown by the arrow in FIG. 1(b), the width direction of the crack K, i.e., the direction in which a pair of wall surfaces of the crack K face each other, is referred to as the "crack width direction (KWD)", and the extension direction of the crack K on the tire surface T01f is referred to as the "crack extension direction (KED)". The extension direction of the crack K (crack extension direction (KED)) is specifically the extension direction of the crack width center line of the crack K on the tire surface T01f. The crack width center line of the crack K is a line connecting the center points of the crack width direction KWD of the crack K at each position of the crack K on the tire surface T01f.

[0020] The tire repair method of this embodiment includes a stapling step. In the stapling step, the crack K is fixed with a staple S (FIG. 1(b)). In this specification, "fixing" the crack K means fixing the shape of the crack K (and therefore the degree of opening). As shown in Fig. 1(b), the staple S is generally U-shaped. The staple S has a pair of legs SL and a connecting portion SB. The connecting portion SB connects one end of the pair of legs SL to each other. More specifically, in the stapling step, a pair of legs SL of the staple needle S are inserted into the side rubber T08 from the tire surface T01f side on both sides of the crack width direction KWD of the crack K. This fixes the crack K with the staple needle S, and thus prevents the crack K from opening any further. In a state where a pair of legs SL of the staple S are inserted into the side rubber T08 (FIG. 1(b)), it is preferable that the pair of legs SL are each separated from the crack K in the crack width direction KWD, i.e., a part of the side rubber T08 is located between the pair of legs SL and the crack K in the crack width direction KWD. It is preferable that the pair of legs SL are not exposed to the crack K. Also, in a state where a pair of legs SL of the staple S are inserted into the side rubber T08 (FIG. 1(b)), it is preferable that the connecting portion SB of the staple S is placed on the tire surface T01f (i.e., is in contact with the tire surface T01f) while straddling the crack K. The stapling step may be performed, for example, by an operator inserting staples S using an instrument such as a stapler or hammer, or may be performed by an operator inserting staples S by hand without using an instrument. After the stapling step, the tire T01 has the cracks K fixed by the staples S (FIGS. 1 and 2).

[0021] As described above, the tire repair method of this embodiment includes a stapling step of fixing the crack K before it reaches the carcass ply T05p with the staple needles S. The crack K has a tendency to grow as it opens up, but according to the above-mentioned stapling step, the staple needles S prevent the crack K from opening any further, so that the growth of the crack K can be effectively prevented before it becomes large, and thus the life of the tire can be effectively extended. If the crack K is repaired using, for example, an adhesive instead of the stapling step, the quality of the repair may vary depending on the skill of the worker. For example, depending on the skill of the worker, the adhesive may not penetrate deep into the crack K, or foreign matter may not be removed sufficiently from the crack K before the adhesive is applied. In such cases, the quality of the repair may be reduced, and the effect of preventing the progression of the crack K may not be sufficiently obtained even after the repair, and the expected effect of extending the tire life due to the repair may not be obtained. On the other hand, the staple step is a relatively simple operation, so it is easy to ensure good repair quality regardless of the skill of the worker. Furthermore, the tire T01 (FIG. 2) obtained by the tire repair method of this embodiment is one that has been repaired with good quality regardless of the skill of the worker, and therefore can have a longer lifespan.

[0022] In the stapling step, since it is sufficient that the distance between a pair of opposing wall surfaces in the crack K is fixed by the staple S, there is no need to close the crack K before inserting the staple S, and the staple S may be inserted while the crack K is open. However, in the stapling step, the crack K may be closed before inserting the staple S.

[0023] In each example described in this specification, it is preferable that the staples S are made of a material harder than rubber (particularly the rubber constituting the side rubber T08). This allows the cracks K to be fixed more firmly by the staples S. From this viewpoint, the material constituting the staple needle S is preferably, for example, resin or metal.

[0024] In each example described in this specification, it is preferable that the staple S is made of resin. Since a tire is repeatedly deformed during driving, or deformed by loading and unloading luggage on a vehicle equipped with the tire, the staple S is subjected to stress in accordance with the deformation of the tire, and is deformed when the stress is large. Since staples made of metal tend to be inferior to resin in terms of the ability to retain their original shape after stress is applied, fatigue accumulates and they tend to break easily every time the tire is deformed. On the other hand, a staple made of resin is less likely to accumulate fatigue even after it is deformed by stress, as it returns to its original shape when the stress is removed, and is therefore superior in terms of durability. Therefore, by using staples made of resin, the crack K can be fixed, and the repair effect is easily maintained even during subsequent use.

[0025] In each example described in this specification, as in the example shown in Fig. 1(b), in the stapling step, the crack K may be fixed by a plurality of staples S. In this case, it is preferable that the plurality of staples S are arranged along the crack extension direction KED (i.e., the crack K is fixed by the staples S as described above at each of a plurality of positions on the crack K in the crack extension direction KED). This makes it possible to fix the crack K more reliably and to more effectively suppress the progression of the crack K. In this case, from the viewpoint of more reliably fixing the crack K, it is preferable that the driving interval P of the staples S (FIG. 1(b)) is 10 mm or less. Here, the driving interval P of the staples S corresponds to the length of a straight line connecting the centers of the crack extension directions KED of each of a pair of adjacent staples S when the crack K is viewed in a plan view from the tire surface T01f side and seen on the center line of the crack width of the crack K. The driving interval P of the staples S may be uniform along the crack extension direction KED as in the example shown in FIG. 1(b), or may be non-uniform along the crack extension direction KED. When the crack K is viewed in plan from the tire surface T01f side, the staples S may be parallel to each other as in the example shown in FIG. 1(b), or may be non-parallel to each other. When the crack K is viewed in plan from the tire surface T01f side, it is preferable that each staple S extends approximately perpendicular to the crack extension direction KED, as in the example shown in FIG. 1(b).

[0026] In each example described in this specification, as shown in Fig. 1(b), it is preferable that the tip ST of the pair of legs SL of the staple S inserted into the side rubber T08 by the staple step is located inside the side rubber T08 and does not reach the carcass ply T05p. This makes it possible to suppress damage to the tire T01 caused by the staple S.

[0027] In each example described in this specification, it is preferable that the length of the pair of legs SL of the staple S is approximately the same as or greater than the depth of the crack K, and it is more preferable that the length is longer than the depth of the crack K. This allows the crack K to be fixed more reliably. From a similar perspective, when the length of the pair of legs SL of the staple S is shorter than the depth of the crack K, it is preferable that the length obtained by subtracting the length of the pair of legs SL of the staple S from the depth of the crack K is 2 mm or less. The depth of the crack K is measured along a direction perpendicular to the tire surface T01f.

[0028] In each of the examples described herein, the tire repair method may include only a stapling step, such as the example shown in FIG.

[0029] FIG. 3 is a diagram for explaining a tire repair method according to a second embodiment of the present invention. In each of the examples described in this specification, the tire repair method may further include an adhesive applying step in addition to the stapling step, as in the second embodiment shown in FIG. FIG. 3(a) shows a schematic view of the vicinity of the crack K of tire T01 after an adhesive application step is performed after the state of FIG. 1(a), and FIG. 3(b) shows a schematic view of the vicinity of the crack K of tire T01 after a stapling step is performed after the state of FIG. 3(a). In the adhesive injection step, the adhesive A1 is injected into the crack K. At this time, the adhesive A1 injected into the crack K is made to contact each of a pair of opposing wall surfaces in the crack K (i.e., the pair of opposing wall surfaces in the crack K are connected to each other via the adhesive A1). The adhesive A1 may be injected by any method, such as injection or application. By the adhesive applying step, a pair of opposing wall surfaces in the crack K are fixed to each other via the adhesive A1, and are prevented from opening further. Therefore, by performing the adhesive applying step in addition to the stapling step, the crack K can be fixed more reliably. In the adhesive injection step, since it is sufficient that the distance between a pair of opposing wall surfaces in the crack K is fixed by the adhesive A1, there is no need to close the crack K after the adhesive A1 is injected, and the crack K may be left open. However, in the adhesive injection step, the crack K may be closed after the adhesive A1 is injected. As shown in the example of Figure 3, it is preferable to perform the adhesive application step before the stapling step, which makes the adhesive application step easier to perform. However, the adhesive application step may be performed in parallel with the stapling step or after the stapling step. After the adhesive introducing step, the tire T01 has the adhesive A1 located within the crack K (FIG. 3). In addition, since the crack K can be sufficiently fixed by the stapling step alone, the adhesive injection step does not need to be performed.

[0030] In the adhesive injection step, the adhesive A1 may be completely filled into the crack K so as to occupy the entire space within the crack K, as in the example shown in FIG. Alternatively, in the adhesive injection step, as long as a pair of opposing wall surfaces in the crack K are connected to each other via the adhesive A1, the adhesive A1 may be partially filled into the crack K so as to occupy only a part of the space in the crack K, as in the modified example shown in Fig. 4. For example, as in the example shown in Fig. 4, the adhesive A1 may be partially filled into the crack K so as to occupy only a portion of the space in the crack K on the opening side (the tire surface T01f side). In this case, too, the adhesive injection step can be simplified and does not require a particularly high level of skill, as compared to the case in which a pair of opposing wall surfaces in the crack K are fixed to each other via the adhesive A1 while the adhesive A1 is completely filled into the crack K, and therefore good repair quality can be easily ensured regardless of the skill of the worker.

[0031] In each of the examples described in this specification, the tip portion ST of each of the pair of legs SL of the staple S may be flat, as in the example shown in FIG. In this specification, the "tip ST" of the leg SL refers to the end opposite the connecting portion SB, out of both ends of the leg SL in the extending direction. In each example described in this specification, the tip portions ST of the pair of legs SL of the staple S may have a curved surface as in the modified example shown in Fig. 5. In this case, the pair of legs SL of the staple S can be easily inserted in the stapling step, and since the tips ST of the legs SL are not sharp, damage to the side rubber T08 of the tire T01 by the tips ST of the legs SL can be suppressed. However, the tip portions ST of the pair of legs SL of the staple S may have a sharp tapered shape.

[0032] In each example described in this specification, one or more barbs SH may be provided on each of a pair of legs SL of the staple S, as in the modified example shown in Fig. 6. The barbs SH extend from the legs SL toward the outer periphery of the legs SL and toward the connecting portion SB in the extending direction of the legs SL (and thus toward the tire surface T01f). The shape of the barbs SH may be arbitrary. Due to the presence of the barb SH, once the staple S has been inserted into the tire T01, the barb SH acts to make it difficult for the staple S to come out of the tire T01. Therefore, the condition of the tire repaired by this tire repair method can be easily maintained for a longer period of time. The barb SH may be connected to the tip ST of the leg SL as in the example of FIG. 6, or may be connected to a portion of the leg SL between the tip ST and the connecting portion SB.

[0033] In each example described in this specification, as in the modified example shown in Fig. 7, at least a part of the surface of each of the pair of legs SL of the staple S may have an uneven portion SU with unevenness. The uneven portion SU includes a number of convex portions. Due to the presence of the uneven portion SU, the staple S once inserted into the tire T01 is less likely to come out of the tire T01 due to the action of the uneven portion SU. Therefore, the state repaired by this tire repair method can be easily maintained for a longer period of time.

[0034] In each example described in this specification, it is preferable that the surface roughness of a part or the whole of each surface of the pair of legs SL of the staple S is as large as possible. In this case, the staple S once inserted into the tire T01 is less likely to come out of the tire T01. Therefore, the state of the tire repaired by this tire repair method can be easily maintained for a longer period of time. In each example described in this specification, it is preferable that the overall surface roughness of each surface of the pair of legs SL of the staple S is as large as possible. In this case, it is possible to prevent the insertion of the staple S in the stapling step from becoming difficult due to the high surface roughness of the legs SL. In addition, as in the modified example shown in Figure 7, when the surface of each of the pair of legs SL of the staple S has an uneven portion SU with unevenness at least in part, it is preferable that the surface roughness of the uneven portion SU satisfies the above numerical range.

[0035] In each example described in this specification, the tire repair method may further include an adhesive coating step of coating at least a part of the surface of the pair of legs SL of the staple S with adhesive A2, as in the third embodiment shown in Fig. 8. The adhesive A2 may be applied by any method, such as application, spraying, dipping, etc. The adhesive coating step is preferably performed before the stapling step. The adhesive coating step makes it difficult for the staples S, once inserted into the tire T01, to fall out of the tire T01 due to the action of the adhesive A2. Therefore, the state of repair by this tire repair method can be easily maintained for a longer period of time.

[0036] The above-mentioned adhesives A1 and A2 may be, for example, one or more types of adhesives selected from an acrylic resin adhesive, an epoxy resin adhesive, a urethane resin adhesive, and a cyanoacrylate adhesive.

[0037] In addition, when the loss of rubber in the crack K is relatively small, the adhesive A1 used in the adhesive applying step may be an acrylic resin adhesive, an epoxy resin adhesive, or the like, which has a relatively high elastic modulus after curing. In this case, the tire T01 is in a state close to the state of the tire before the damage after the repair, so that the repaired portion can be prevented from being damaged again. This can extend the life of the tire T01.

[0038] If the crack K has a relatively large amount of rubber loss, the adhesive A1 used in the adhesive applying step may be a urethane resin adhesive or the like, which has a lower elastic modulus after curing than acrylic resin adhesives, epoxy resin adhesives, etc. In this case, the cured adhesive A1 is more likely to deform in conjunction with the surrounding side rubber T08, so that the repaired portion can be prevented from being damaged again, thereby extending the life of the tire T01.

[0039] The elastic modulus of the adhesives A1 and A2 after curing is preferably 4.0 MPa or more and 500 MPa or less at 25° C. and 1.0 MPa or more and 300 MPa or less at 60° C. Sufficient peel adhesion strength can be obtained when the elastic modulus of the adhesives A1 and A2 after curing is 4.0 MPa or more at 25° C. and 1.0 MPa or more at 60° C. Furthermore, when the elastic modulus of the adhesives A1 and A2 after curing is 500 MPa or less at 25° C. and 300 MPa or less at 60° C., the adhesives A1 and A2 can sufficiently follow tire deformation and suppress cracking.

[0040] In each example described in this specification, a foreign matter removal step may be performed before the adhesive introduction step to remove foreign matter and the like from within the crack K. This can increase the adhesive strength of the adhesive A1.

[0041] In each example described in this specification, a surface treatment step may be performed to at least the area to which the adhesive A1 is applied among the surfaces in the crack K (for example, a pair of opposing wall surfaces in the crack K). In this case, the surface roughness of the surface in the crack K may be adjusted by buffing the surface in the crack K before the surface treatment is performed. The surface treatment step is preferably carried out after the foreign matter removal step and before the adhesive application step.

[0042] In the surface treatment step, the surface in the crack K may be treated by applying a primer to the surface by a primer application means. However, the method of surface treatment is not limited to this. For example, as physical methods, corona treatment, plasma treatment, treatment by ultraviolet light, treatment by flame, buffing, etc. can be applied, and as chemical methods, silane coupling treatment, graft treatment, etc. can be applied.

[0043] When a primer is used for the surface treatment in the surface treatment step, it is possible not only to increase the adhesive strength of the adhesive A1, but also to easily impart functions such as stabilizing the surface after surface treatment and preventing deterioration of the adhesive A1.

[0044] The primer used for the surface treatment here may be, for example, a hypochlorous acid aqueous solution. Specifically, the hypochlorous acid aqueous solution preferably has an effective chlorine concentration in the liquid of 100 ppm or more and 13000 ppm or less, and a pH value of 2 or more and 7 or less. The pH value is more preferably in the range of 4 or more and 7 or less. When such a hypochlorous acid aqueous solution is used as the primer 50, the adhesive surface of the rubber is chlorinated, thereby improving the wettability of the adhesive A1 to the rubber surface. This can increase the adhesive strength of the adhesive A1. When the pH value of the hypochlorous acid aqueous solution is in the range of 4 or more and 7 or less, the adhesive strength of the adhesive A1 is further improved.

[0045] In addition, the concentration of the secondary amine-based antioxidant in the rubber is preferably 1% or less at the adhesion surface of the rubber to which the primer is applied. When the concentration of the secondary amine-based antioxidant in the rubber is 1% or less, the concentration of the antioxidant near the adhesion interface becomes sufficiently low, improving the peel adhesion strength.

[0046] In addition, at the adhesive interface of rubber after chlorination treatment with a hypochlorous acid solution or the like is performed as a surface treatment, the amount of halogen element at the rubber side position 1 μm from the adhesive interface is 300% or more of the amount of halogen element at the rubber side position 15 μm from the adhesive interface. When the amount of halogen element at the adhesive interface of rubber satisfies this relationship, the halogen element hardly reaches the rubber side position 15 μm from the interface. Therefore, it is possible to suppress the rubber from hardening due to structural changes and reducing its strength.

[0047] In addition, at the adhesive interface of the rubber, if the above relationship is satisfied and the halogen element reaches a position on the rubber side about 4 to 5 μm from the adhesive interface, the adhesive strength of the adhesive A1 can be further increased.

[0048] The tire T01 may have any internal structure. An example of the internal structure of the tire T01 will be described below with reference to FIG. FIG. 2 is a cross-sectional view in the tire width direction showing a tire half portion (specifically, a portion on one side of the tire equatorial plane CL) of a tire T01 according to one embodiment of the present invention. The tire T01 of the embodiment of Fig. 2 is configured as a heavy-duty pneumatic tire (for example, an off-the-road (construction vehicle) pneumatic tire, etc.). However, the tire T01 of any embodiment of the present invention may be configured as any type of tire.

[0049] As shown in Fig. 2, the tire T01 includes a tread portion T01t, a pair of sidewall portions T01w extending radially inward from both ends of the tread portion T01t in the tire width direction, and a pair of bead portions T01b provided at the ends of the sidewall portions T01w on the inner side in the tire radial direction. When the tire T01 is mounted on a rim, the bead portions T01b are configured to contact the rim on the inner side in the tire radial direction and the outer side in the tire width direction. The tire T01 has a pair of tire side portions T01s. The tire side portions T01s include the sidewall portions T01w and the bead portions T01b. The tire T01 also includes a pair of bead cores T02, a pair of bead fillers T03, a carcass T05, a belt T06, a tread rubber T07, a side rubber T08, and an inner liner T09.

[0050] Each bead core T02 is embedded in the corresponding bead portion T01b. The bead core T02 includes a plurality of bead wires covered with rubber. The bead wires are preferably made of metal (e.g., steel), but may be made of organic fibers such as polyester, nylon, rayon, and aramid. The bead wires may be made of, for example, monofilament or stranded wire.

[0051] Each bead filler T03 is located on the outer side in the tire radial direction with respect to the corresponding bead core T02. The bead filler T03 extends in a tapered shape toward the outer side in the tire radial direction. The bead filler T03 is made of rubber. In general, the bead filler is sometimes called a "stiffener." As shown in FIG. 2, the bead filler T03 may be composed of a plurality of bead filler portions T031, T032 (two in the example of FIG. 2). The rubber compositions constituting the plurality of bead filler portions T031, T032 are different from each other. However, the rubber compositions constituting the respective bead filler portions T031, T032 are substantially the same throughout the bead filler portions T031, T032. The plurality of bead filler portions T031, T032 may have different hardnesses, for example. The plurality of bead filler portions T031, T032 are arranged (stacked) along, for example, the tire radial direction. For example, the bead filler portion T032 located at the outermost position in the tire radial direction among the plurality of bead filler portions T031, T032 may be softer than the other bead filler portions T031. Alternatively, the bead filler T03 may be composed of only one bead filler portion, in other words, the composition of the rubber constituting the bead filler T03 may be substantially the same throughout the bead filler T03.

[0052] The carcass T05 straddles a pair of bead cores T02 and extends in a toroidal shape. The carcass T05 is composed of one or more carcass plies T05p (one in the example of FIG. 2). Each carcass ply T05p includes one or more carcass cords T05c and a covering rubber T05r that covers the carcass cords T05c. The carcass cords T05c can be formed of a monofilament or a twisted wire. The carcass cord T05c is preferably made of metal (for example, steel), but may be made of organic fibers such as polyester, nylon, rayon, and aramid. The carcass T05 is preferably of radial construction, but may also be of bias construction.

[0053] The belt T06 is disposed on the outer side in the tire radial direction with respect to the crown portion of the carcass T05. The belt T06 includes one or more belt plies T06p (four layers in the example of FIG. 2). Each belt ply T06p includes one or more belt cords and a coating rubber that covers the belt cords. The belt cords can be formed of a monofilament or a twisted wire. The belt cords may be made of a metal (e.g., steel) or an organic fiber made of polyester, nylon, rayon, aramid, or the like.

[0054] The tread rubber T07 is located on the outer side of the belt T06 in the tire radial direction in the tread portion T01t. The tread rubber T07 constitutes a tread surface, which is the outer surface of the tread portion T01t in the tire radial direction. A tread pattern is formed on the tread surface.

[0055] The side rubber T08 is located on the tire side portion T01s. The side rubber T08 constitutes the tire surface T01f (the outer surface on the outer side in the tire width direction) of the tire side portion T01s. The side rubber T08 is located on the outer side in the tire width direction than the carcass T05. The side rubber T08 is located on the outer side in the tire width direction than the bead filler T03. The side rubber T08 is formed integrally with the tread rubber T07.

[0056] The inner liner T09 is disposed on the tire inner side of the carcass T05, and may be laminated on the tire inner side of the carcass T05, for example. The inner liner T09 is made of, for example, a butyl-based rubber having low air permeability. The butyl-based rubber includes, for example, butyl rubber and its derivative, halogenated butyl rubber. The inner liner T09 is not limited to a butyl-based rubber, and may be made of other rubber compositions, resins, or elastomers.

[0057] As shown in Fig. 2, the tire T01 may include a cushion rubber T10 between the carcass T05 and the tread rubber T07 in the tire radial direction. The cushion rubber T10 may be located near the end of the belt T06 in the tire width direction, as in the example of Fig. 2.

[0058] As shown in FIG. 2, the tire T01 may be provided with a rubber chafer T11 at a portion of each bead portion T01b that is configured to come into contact with the rim.

[0059] As shown in Fig. 2, the tire T01 may include one or more (one in the example of Fig. 2) wire chafers T14 around each bead core T02. The wire chafer T14 may be disposed on the opposite side of the carcass T05 from the bead core T02, as in the example of Fig. 2. The wire chafer T14 is made of metal (e.g., steel). As shown in Fig. 2, the tire T01 may be provided with one or more (two in the example of Fig. 2) nylon chafers T13 around each bead core T02. The nylon chafers T13 may be disposed on the opposite side of the carcass T05 from the bead cores T02, as in the example of Fig. 2. The nylon chafers T13 are made of nylon. In the example of FIG. 2, each nylon chafer T13 is disposed on the opposite side of the wire chafer T14 from the bead core T02.

[0060] As shown in FIG. 2, the tire T01 may include a hat rubber T12 between the bead filler T03 and the side rubber T08 in the tire width direction in each tire half portion. In the example of FIG. 2, the hat rubber T12 is disposed between the bead filler T03 and each nylon chafer T13 in the tire width direction.

[0061] The tire T01 may include an RF tag 10 as a communication device. The RF tag 10 includes an IC chip and an antenna. The RF tag 10 may be arranged, for example, sandwiched between a plurality of members of the same type or different types that constitute the tire T01. In this way, the RF tag 10 can be easily attached during the production of the tire T01, and the productivity of the tire T01 equipped with the RF tag 10 can be improved. As in the example of FIG. 2, the RF tag 10 may be arranged, for example, sandwiched between the bead filler T03 and another member adjacent to the bead filler T03. The RF tag 10 may be embedded in any of the members constituting the tire T01. In this way, the load applied to the RF tag 10 can be reduced compared to when the RF tag 10 is sandwiched between multiple members constituting the tire T01. This improves the durability of the RF tag 10. In this example, the RF tag 10 may be embedded in a rubber member such as the tread rubber T07 or the side rubber T08. It is preferable that the RF tag 10 is not disposed at a position that is a boundary between members having different rigidity in the periphery length direction, which is a direction along the tire outer surface in a cross-sectional view in the tire width direction. In this way, the RF tag 10 is not disposed at a position where distortion is likely to concentrate due to a rigidity difference. Therefore, the load applied to the RF tag 10 can be reduced. This makes it possible to improve the durability of the RF tag 10. In this example, it is preferable that the RF tag 10 is not disposed at a position that is a boundary between an end of the carcass T05 and a member adjacent to the end of the carcass T05 (e.g., a side rubber T08, etc.) in a cross-sectional view in the tire width direction. The number of RF tags 10 is not particularly limited. The tire T01 may include only one RF tag 10, or may include two or more RF tags 10. Here, the RF tag 10 is illustrated as an example of a communication device, but a communication device different from the RF tag 10 may be used.

[0062] The RF tag 10 may be placed, for example, in the tread portion T01t of the tire T01. In this manner, the RF tag 10 will not be damaged by a side cut of the tire T01. The RF tag 10 may be disposed, for example, in the tread center in the tire width direction. The tread center is a position where deflection is unlikely to concentrate in the tread portion T01t. This reduces the load applied to the RF tag 10. This improves the durability of the RF tag 10. Also, it is possible to suppress differences in communication with the RF tag 10 from both outer sides of the tire T01 in the tire width direction. In this example, the RF tag 10 may be disposed, for example, in the tire width direction within a range of 1 / 2 the tread width centered on the tire equatorial plane CL. The RF tag 10 may be arranged, for example, at a tread end in the tire width direction. If the position of a reader that communicates with the RF tag 10 is predetermined, the RF tag 10 may be arranged, for example, at one tread end closer to the reader. In this example, the RF tag 10 may be arranged, for example, within a range of 1 / 4 of the tread width in the tire width direction, with the tread end as the outer end.

[0063] The RF tag 10 may be disposed, for example, on the tire cavity side of the carcass T05 including one or more carcass plies T05p that span between the bead portions T01b. In this manner, the RF tag 10 is less likely to be damaged by impacts applied from the outside of the tire T01, or damage such as side cuts and nail penetration. As an example, the RF tag 10 may be disposed in close contact with the surface of the carcass T05 on the tire cavity side (see point P32 in FIG. 2). As another example, when there is another member on the tire cavity side of the carcass T05, the RF tag 10 may be disposed, for example, between the carcass T05 and another member located on the tire cavity side of the carcass T05. An example of another member located on the tire cavity side of the carcass T05 is the inner liner T09 that forms the tire inner surface. As another example, the RF tag 10 may be attached to the tire inner surface facing the tire cavity (see points P31, P33, and P34 in FIG. 2). By configuring the RF tag 10 to be attached to the inner surface of the tire, it is easy to attach the RF tag 10 to the tire T01 and to inspect and replace the RF tag 10. In other words, it is possible to improve the ease of attachment and maintenance of the RF tag 10. Furthermore, by attaching the RF tag 10 to the inner surface of the tire, it is possible to prevent the RF tag 10 from becoming the core of a tire malfunction, compared to a configuration in which the RF tag 10 is buried inside the tire T01. Furthermore, when the carcass T05 includes a plurality of carcass plies T05p and there is a position where the plurality of carcass plies T05p are overlapped, the RF tag 10 may be disposed between the overlapped carcass plies T05p.

[0064] For example, the RF tag 10 may be disposed on the tread portion T01t of the tire T01 outside the belt T06 including one or more belt plies T06p in the tire radial direction. As an example, the RF tag 10 may be disposed on the outer side of the belt T06 in the tire radial direction and in close contact with the belt T06 (see point P43 in FIG. 2). As another example, in the case where a belt reinforcing layer is provided, the RF tag 10 may be disposed on the outer side of the belt reinforcing layer in the tire radial direction and in close contact with the belt reinforcing layer. As another example, the RF tag 10 may be embedded in the tread rubber T07 outside the belt T06 in the tire radial direction (see point P41 in FIG. 2). By disposing the RF tag 10 on the outer side of the belt T06 in the tire radial direction in the tread portion T01t of the tire T01, communication with the RF tag 10 from the outside of the tire T01 in the tire radial direction is less likely to be hindered by the belt T06. Therefore, it is possible to improve communication with the RF tag 10 from the outside of the tire T01 in the tire radial direction. Also, the RF tag 10 may be arranged, for example, in the tread portion T01t of the tire T01, on the inner side in the tire radial direction of the belt T06. In this way, the outer side of the RF tag 10 in the tire radial direction is covered by the belt T06, so that the RF tag 10 is less likely to be damaged by impact from the tread surface, nail penetration, and the like. As one example of this, the RF tag 10 may be arranged in the tread portion T01t of the tire T01, between the belt T06 and the carcass T05 located on the inner side in the tire radial direction of the belt T06 (see point P44 in FIG. 2). Furthermore, when the belt T06 includes a plurality of belt plies T06p, the RF tag 10 may be disposed between any two belt plies T06p in the tread portion T01t of the tire T01 (see point P42 in FIG. 2). In this manner, the outer side of the RF tag 10 in the tire radial direction is covered with one or more belt plies T06p, so that the RF tag 10 is less susceptible to damage due to impact from the tread surface, nail penetration, and the like.

[0065] The RF tag 10 may be arranged, for example, sandwiched between the cushion rubber T10 and the tread rubber T07 or between the cushion rubber T10 and the side rubber T08 (see points P51 and P53 in FIG. 2). In this way, the impact on the RF tag 10 can be mitigated by the cushion rubber T10. Therefore, the durability of the RF tag 10 can be improved. The RF tag 10 may be embedded in the cushion rubber T10. The cushion rubber T10 may be made up of a plurality of adjacent rubber members of the same or different types. In this case, the RF tag 10 may be sandwiched between the plurality of rubber members constituting the cushion rubber T10 (see point P52 in FIG. 2). This configuration is particularly suitable when the tire T01 is a heavy-duty pneumatic tire (for example, a pneumatic tire for trucks and buses, an off-the-road (for construction vehicles) pneumatic tire, etc.).

[0066] The RF tag 10 may be disposed, for example, at the position of the sidewall portion T01w or the bead portion T01b of the tire T01. The RF tag 10 may be disposed, for example, at one sidewall portion T01w or one bead portion T01b close to a reader capable of communicating with the RF tag 10. In this manner, it is possible to improve the communication between the RF tag 10 and the reader. As an example, the RF tag 10 may be disposed between the carcass T05 and the side rubber T08 or between the tread rubber T07 and the side rubber T08 (see points P61 and P63 in FIG. 2). For example, the RF tag 10 may be disposed between the position of the maximum tire width and the position of the tread surface in the tire radial direction. In this manner, it is possible to improve communication with the RF tag 10 from the outside of the tire T01 in the tire radial direction, compared to a configuration in which the RF tag 10 is disposed on the inner side in the tire radial direction from the position of the maximum tire width. The RF tag 10 may be arranged, for example, radially inward of the position where the tire is at its widest point. In this way, the RF tag 10 is arranged in the vicinity of the bead portion T01b, which has high rigidity. Therefore, the load applied to the RF tag 10 can be reduced. This improves the durability of the RF tag 10. As an example, the RF tag 10 may be arranged in a position adjacent to the bead core T02 in the tire radial direction or tire width direction (see point P62 in FIG. 2). Distortion is less likely to concentrate in the vicinity of the bead core T02. Therefore, the load applied to the RF tag 10 can be reduced. This improves the durability of the RF tag 10. In particular, it is preferable to place the RF tag 10 in a position radially inward of the tire's maximum width position and radially outward of the bead core T02 of the bead portion T01b. This can improve the durability of the RF tag 10, and can improve the communication performance of the RF tag 10 by preventing communication between the RF tag 10 and a reader from being hindered by the bead core T02. In addition, when the side rubber T08 is composed of multiple rubber members of the same or different types adjacent to each other in the tire radial direction, the RF tag 10 may be positioned by being sandwiched between the multiple rubber members that make up the side rubber T08.

[0067] The RF tag 10 may be disposed by being sandwiched between the stiffener T03 and a member adjacent to the stiffener T03. In this way, the RF tag 10 can be disposed at a position where distortion is less likely to be concentrated by disposing the stiffener T03. Therefore, the load applied to the RF tag 10 can be reduced. This can improve the durability of the RF tag 10. The RF tag 10 may be disposed by being sandwiched between the stiffener T03 and a side rubber T08, for example (see point P74 in FIG. 2). Also, the RF tag 10 may be disposed, for example, sandwiched between the stiffener T03 and the carcass T05 (see point P72 in FIG. 2). The portion of the carcass T05 that sandwiches the RF tag 10 together with the stiffener T03 may be located on the outer side in the tire width direction relative to the stiffener T03, or may be located on the inner side in the tire width direction. When the portion of the carcass T05 that sandwiches the RF tag 10 together with the stiffener T03 is located on the outer side in the tire width direction relative to the stiffener T03, the load applied to the RF tag 10 due to impact or damage from the outside of the tire T01 in the tire width direction can be further reduced. This can further improve the durability of the RF tag 10. The stiffener T03 may have a portion disposed adjacent to the rubber chafer T11. In this case, the RF tag 10 may be disposed by being sandwiched between the stiffener T03 and the rubber chafer T11. The stiffener T03 may have a portion adjacent to the hat rubber T12 on the outer side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the stiffener T03 and the hat rubber T12 (see point P71 in FIG. 2). The stiffener T03 may be made up of multiple rubber members with different hardnesses. In this case, the RF tag 10 may be sandwiched between the multiple rubber members that make up the stiffener T03 (see point P73 in FIG. 2). The RF tag 10 may be disposed by being sandwiched between the hat rubber T12 and a member adjacent to the hat rubber T12. For example, the RF tag 10 may be disposed by being sandwiched between the hat rubber T12 and the carcass ply T05p. In this way, the impact on the RF tag 10 can be mitigated by the hat rubber T12. Therefore, the durability of the RF tag 10 can be improved. This configuration is particularly suitable when the tire T01 is a heavy-duty pneumatic tire (for example, a pneumatic tire for trucks and buses, an off-the-road (for construction vehicles) pneumatic tire, etc.).

[0068] The RF tag 10 may be arranged, for example, sandwiched between the rubber chafer T11 and the side rubber T08 (see point P8 in FIG. 2). In this way, the RF tag 10 can be arranged in a position where distortion is less likely to be concentrated due to the placement of the rubber chafer T11. This reduces the load applied to the RF tag 10. This improves the durability of the RF tag 10. The RF tag 10 may be disposed, for example, sandwiched between the rubber chafer T11 and the carcass T05. In this way, the load applied to the RF tag 10 due to impact or damage from the rim can be reduced. Therefore, the durability of the RF tag 10 can be improved.

[0069] The RF tag 10 may be sandwiched between the nylon chafer T13 and another member adjacent to the nylon chafer T13 on the outer or inner side in the tire width direction. In this way, the position of the RF tag 10 is less likely to change when the tire is deformed. Therefore, the load applied to the RF tag 10 when the tire is deformed can be reduced. This can improve the durability of the RF tag 10. The nylon chafer T13 may have a portion adjacent to the rubber chafer T11, for example, on the outer side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and the rubber chafer T11 (see point P101 in FIG. 2). The nylon chafer T13 may have a portion adjacent to the side rubber T08, for example, on the outer side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and the side rubber T08 (see point P91 in FIG. 2). The nylon chafer T13 may have a portion adjacent to the stiffener T03, for example, on the inner side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and the stiffener T03. The nylon chafer T13 may also have a portion adjacent to the hat rubber T12, for example, on the inner side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and the hat rubber T12 (see point P92 in FIG. 2). Furthermore, the nylon chafer T13 may have a portion adjacent to the carcass T05, for example, on the inner side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and the carcass T05. Furthermore, the nylon chafer T13 may have a portion adjacent to the wire chafer T14, for example, on the inner side in the tire width direction. In this case, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and the wire chafer T14. In this way, the RF tag 10 may be disposed by being sandwiched between the nylon chafer T13 and another member adjacent to the outer or inner side in the tire width direction of the nylon chafer T13. In particular, by covering the outer side of the RF tag 10 in the tire width direction with the nylon chafer T13, the load applied to the RF tag 10 due to impact or damage from the outside of the tire in the tire width direction can be further reduced. Therefore, the durability of the RF tag 10 can be further improved. This configuration is particularly suitable when the tire T01 is a heavy-duty pneumatic tire (for example, a pneumatic tire for trucks and buses, an off-the-road (for construction vehicles) pneumatic tire, etc.).

[0070] The RF tag 10 may be disposed by being sandwiched between the wire chafer T14 and another member adjacent to the wire chafer T14 on the inner or outer side in the tire width direction (see point P102 in FIG. 2). In this manner, the position of the RF tag 10 is less likely to fluctuate when the tire is deformed. Therefore, the load applied to the RF tag 10 when the tire is deformed can be reduced. This can improve the durability of the RF tag 10. The other member adjacent to the wire chafer T14 on the inner or outer side in the tire width direction may be, for example, a rubber member such as a rubber chafer T11. Also, the other member adjacent to the wire chafer T14 on the inner or outer side in the tire width direction may be, for example, a carcass T05. EXAMPLES

[0071] The tire repair method of Comparative Example 1 and Examples 1 to 7 was evaluated through experiments, which will be described below. In each of the comparative examples and examples, tires of the same type and size were used. Details of the tire repair method and crack K in each of the comparative examples and examples are as shown in Table 1. In Comparative Example 1, the crack K was not repaired. In Examples 1 to 5, only the stapling step was performed. In Examples 6 and 7, an adhesive introducing step and a subsequent stapling step were performed. The adhesive A1 introduced into the crack K in the adhesive introducing step occupied only the portion of the space in the crack K on the tire surface T01f side, and therefore the depth of the adhesive A1 was shallower than the depth of the crack K. In Table 1, the "surface roughness of the leg SL" of the staple S is shown by converting the arithmetic mean height Sa of the surface roughness of the leg SL into an index value. The higher the index value, the greater the surface roughness (i.e., the rougher). In each comparative example and example, after repair, the tire was mounted on a vehicle and the vehicle was driven under specified conditions, after which the amount of progression of the crack K in the depth direction was measured, and the crack progression inhibition effect of the tire repair method was evaluated based on the measurement results. The results are shown in Table 1. The crack progression inhibition effect was evaluated on a four-level scale: excellent, good, fair, and poor. The order of increasing crack progression inhibition effect is excellent > good > fair > poor.

[0072] [Table 1]

[0073] As can be seen from Table 1, in comparison with Comparative Example 1, Examples 1 to 7 exhibited a higher crack propagation suppression effect.

[0074] [Contribution to the United Nations-led Sustainable Development Goals (SDGs)] The SDGs have been proposed to realize a sustainable society. One embodiment of the present invention is considered to be a technology that can contribute to "No. 12_Responsible Consumption and Production" and "No. 13_Concrete measures against climate change." [Industrial Applicability]

[0075] The tire repair method and tire according to the present invention can be suitably used for any type of pneumatic tire, for example, a heavy-duty pneumatic tire (for example, an off-the-road (construction vehicle) pneumatic tire, etc.). [Explanation of symbols]

[0076] T01: Tires T01t: tread portion, T01w: sidewall portion, T01b: bead portion, T01s: tire side portion, T01f: tire surface, T02: Bead core, T03: Bead filler (stiffener), T031, T032: Bead filler part, T05: Carcass, T05p: Carcass ply, T05c: Carcass cord, T05r: Covering rubber, T06: Belt, T06p: Belt ply, T07: Tread rubber, T08: Side rubber, T09: Inner liner, T10: Cushion rubber, T11: Rubber chafer, T12: Hat rubber, T13: Nylon chafer, T14: Wire chafer, CL: tire equatorial plane, 10: RF tag K: Cracks, S: Staple, SL: Leg, SH: Barb, SU: Concave, ST: Tip, SB: Joint, A1, A2: Adhesive

Claims

1. A tire repair method for repairing a crack that is formed in a side rubber located between a carcass ply and a tire surface in a tire side portion of a tire and that terminates within the side rubber, comprising: The tire repair method includes a stapling step of fixing the crack with staples.

2. 2. The tire repair method of claim 1, wherein the staples are constructed from a material harder than rubber.

3. 2. The tire repair method according to claim 1, wherein the staples are made of resin.

4. 2. The tire repair method according to claim 1, wherein the staples are driven at intervals of 10 mm or less.

5. The tire repair method of claim 1 further comprising the step of injecting an adhesive into the crack.

6. Each of the pair of legs of the staple is provided with a barb, or The surface of each of the pair of legs of the staple has an uneven portion having an uneven surface.

2. The tire repair method according to claim 1.

7. 2. The tire repair method according to claim 1, further comprising an adhesive coating step of coating a surface of a pair of legs of the staple needle with an adhesive.

8. A tire, wherein a crack formed in a side rubber located between a carcass ply and a tire surface in a tire side portion and terminating within the side rubber is fixed by a staple.

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