JP5495444B2 - Pneumatic tire - Google Patents

Description

  The present invention relates to a pneumatic tire including a pair of annular bead cores, a bead filler disposed on the outer peripheral side of the beat core, and a carcass layer whose end side is wound up from the inner side in the width direction by the bead core.

  In general, a pneumatic tire has a carcass layer composed of at least one layer of a carcass ply, with a pair of annular bead cores whose end portions are wound up from the inner side in the width direction. At the winding end of the carcass layer on the outer side in the tire radial direction, stress is concentrated during running of the tire, and separation may occur in the rubber starting from this portion, leading to a tire failure. Therefore, in order to improve the durability of the tire, a reinforcing member that reinforces the vicinity of the winding end of the carcass ply is generally provided.

  For example, in Patent Document 1 below, for the purpose of improving the separation resistance (durability) of the rolled-up end of the carcass layer, an organic fiber having an inclination angle in the range of 80 to 100 ° with respect to the radial direction of the tire. A pneumatic tire having a configuration in which a wound end of a carcass layer is covered with a reinforcing cord layer formed by rubber-coating the cord is described. However, such a reinforcing cord layer cannot sufficiently reinforce the vicinity of the rolled-up end of the carcass layer, and the effect of improving the separation resistance is not sufficient.

  In Patent Document 2 below, for the purpose of improving durability, a hard rubber sheet is arranged in the vicinity of the outer end in the tire radial direction of the bead reinforcement layer, or the outer end in the tire radial direction of the bead reinforcement layer is composed of two hard rubber sheets. A pneumatic tire having a configuration for sandwiching a tire is described. However, reinforcement with a hard rubber sheet increases the tire weight, which is not preferable in view of the fuel efficiency of the tire. In addition, reinforcement with a hard rubber sheet is not preferable because it increases the thickness in the tire width direction.

  In Patent Document 3 below, for the purpose of reducing the weight of the tire without reducing the durability, no bead filler is disposed around the bead core, and only the carcass layer is wound up from the inside to the outside, and the carcass layer is wound up. A pneumatic tire is described in which a resin film is disposed so as to cover the end. However, merely disposing a resin film without disposing a bead filler is not sufficient to reinforce the rolled-up end of the carcass layer, and there is a concern about deterioration of durability. Further, if only a resin film is provided without providing a bead filler, the longitudinal rigidity during running of the tire is lowered and the steering stability of the tire is deteriorated.

  In Patent Document 4 listed below, for the purpose of improving durability, an organic fiber cord reinforcing layer formed by coating an organic fiber cord with rubber is used to wrap up the rolled-up end of the carcass ply, and a high-hardness rubber and a medium are wrapped in the wrapped inner and outer regions. Pneumatic tires each having a hard rubber are described. However, in such a pneumatic tire, in addition to the organic fiber cord reinforcing layer, a high-hardness rubber and a medium-hardness rubber are disposed, so that the longitudinal rigidity during running of the tire is excessively increased and the riding comfort is deteriorated.

  As described above, it has been difficult to improve the tire durability, steering stability, and riding comfort in a well-balanced manner while reducing the weight of the tire.

JP 2001-47821 A JP 2000-301919 A Japanese Patent Laid-Open No. 10-35231 Japanese Patent Laid-Open No. 05-77616

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a pneumatic tire that improves the durability, steering stability, and riding comfort of the tire in a well-balanced manner while reducing the weight of the tire. It is in.

  The above object can be achieved by the present invention as described below. That is, the pneumatic tire according to the present invention includes a pair of annular bead cores, a bead filler disposed on the outer peripheral side of the beat core, a carcass layer in which an end side is rolled up from the inner side in the width direction in the bead core, A pneumatic tire comprising: an outer reinforcing layer disposed at a width direction outer side of the winding end of the carcass layer and covering at least the winding end of the carcass layer, wherein the outer reinforcing layer substantially covers the resin film in the circumferential direction. It is characterized by being formed by being spirally wound along.

  In the pneumatic tire described above, the winding end of the carcass layer is covered by the outer reinforcing layer formed by spirally winding the resin film substantially along the circumferential direction. The separation can be prevented. As a result, the durability of the tire can be improved. Further, since the longitudinal rigidity can be appropriately increased by the bead filler and the outer reinforcing layer, it is possible to improve the steering stability and the riding comfort with a good balance. Moreover, since the outer reinforcing layer is formed of a high-strength and thin resin film, the thickness of the outer reinforcing layer can be reduced, and the weight of the tire can be reduced.

  In the pneumatic tire, the resin film constituting the outer reinforcing layer is preferably a polyethylene naphthalate (hereinafter also referred to as “PEN”) film. PEN has excellent tensile modulus (modulus), high strength, and thermal stability. Therefore, by forming the outer reinforcing layer with the PEN film, separation based on the vicinity of the wound-up end of the carcass layer can be reliably prevented even under high heat generation during high speed running. In addition, although the PEN film is thin and light and has an excellent modulus and high strength, the outer reinforcing layer can be further thinned and the tire can be lightened.

  In the pneumatic tire, it is preferable that the thickness of the outer reinforcing layer in the vicinity of the rolled-up end of the carcass layer is larger than the thickness of other portions of the outer reinforcing layer. According to this configuration, the strength of the outer reinforcing layer in the vicinity of the winding end of the carcass layer is increased, so that separation based on the vicinity of the winding end of the carcass layer can be more reliably prevented. Here, in the present invention, “in the vicinity of the winding end of the carcass layer” means a region within 15 mm outside and inside the tire radial direction from the position in the tire radial direction of the winding end of the carcass layer.

  The pneumatic tire includes an inner reinforcing layer that is disposed on the inner side in the width direction of the rolled-up end of the carcass layer and on the outer side in the width direction of the bead filler, and covers at least the rolled-up end of the carcass layer, and the inner reinforcing layer is substantially In particular, it is preferable to include a plurality of resin films extending in the circumferential direction. According to such a configuration, the winding end of the carcass layer is covered from the outer side in the width direction while the winding end of the carcass layer is covered from the inner side in the width direction by covering the winding end of the carcass layer from the outer side in the width direction. Separation can be prevented more reliably.

  However, if the thickness of the inner reinforcing layer is increased, the longitudinal rigidity during running of the tire is excessively increased, and there is a concern that the riding comfort is deteriorated. Therefore, in order to improve tire separation resistance (durability) and prevent deterioration in riding comfort, the thickness of the outer reinforcing layer in the vicinity of the rolled-up end of the carcass layer is the thickness of the inner reinforcing layer. It is preferable that it is larger than.

  In the pneumatic tire, it is preferable that the plurality of resin films included in the inner reinforcing layer are arranged with a space therebetween. As described above, in order to increase the separation resistance, it is useful to increase the reinforcing effect in the vicinity of the winding end of the carcass layer, but if the reinforcing effect is too high, the longitudinal rigidity at the time of running the tire is too high, There is a concern that the riding comfort deteriorates. However, when the plurality of resin films included in the inner reinforcing layer are arranged with a space between each other, the longitudinal rigidity during running of the tire is appropriately reduced while maintaining the reinforcing effect of the inner reinforcing layer. Therefore, the durability and handling stability of the tire and the riding comfort can be improved in a well-balanced manner.

  In the pneumatic tire, it is preferable that the resin film constituting the inner reinforcing layer is a polyethylene naphthalate film. The inner reinforcement layer, which includes a PEN film with excellent tensile modulus (modulus), high strength, and thermal stability, reduces the weight of the inner reinforcement layer and ensures separation based on the vicinity of the rolled-up end of the carcass layer. Can be prevented.

  In the pneumatic tire, the resin film constituting the inner reinforcing layer is preferably a rubber-coated resin film obtained by rubber-coating a resin film. The rubber-coated resin film that has been coated with rubber in a state where the resin films are spaced apart in advance has higher rubber adhesion to the carcass layer and other members in contact with the inner reinforcing layer. For this reason, it is possible to more reliably prevent separation of the rolled-up end of the carcass layer. Moreover, since the resin films are arranged in a state of being spaced apart in the rubber-coated resin film, it is possible to moderate moderately the increase in longitudinal rigidity during tire travel. As a result, the riding comfort of the tire can be improved.

Tire meridian cross-sectional view showing an example of a pneumatic tire according to the present invention An example of an enlarged view showing the bead portion of FIG. The other example of the enlarged view which shows the bead part of the pneumatic tire which concerns on this invention The other example of the enlarged view which shows the bead part of the pneumatic tire which concerns on this invention The other example of the enlarged view which shows the bead part of the pneumatic tire which concerns on this invention Example of enlarged view of inner reinforcement layer made of rubber-coated PEN film

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a tire meridian cross-sectional view showing an example of a pneumatic tire according to the present invention.

  A pneumatic tire shown in FIG. 1 includes a pair of bead portions 1, a sidewall portion 2 that extends outward in the tire radial direction from each bead portion 1, and a tread portion 3 that is continuous with each tire radial direction outer end of the sidewall portion 2. And a carcass layer 4 in which the end side is wound up from the inner side in the width direction by a pair of annular bead cores 1a, and a belt layer 5 disposed on the outer peripheral side (outer side in the tire radial direction) of the carcass layer 4. The bead portion 1 is provided with an annular bead core 1a formed by covering a converging body such as a steel wire with rubber and a bead filler 1b made of hard rubber.

  In this embodiment, main grooves 31 and 32 extending in the tire circumferential direction are formed in the tread portion 3, and land portions partitioned by these are formed. The land portion may be a rib, or may be a block defined by main grooves 31 and 32 and a lateral groove (not shown) extending in the tire width direction.

  The belt layer 5 is composed of two belt plies, and the carcass layer 4 is reinforced by the effect of these belt plies. The belt ply is formed by covering a reinforcing element (cord) extending at an angle of 19 to 30 ° with respect to the tire circumferential direction (tire equator line C), and the cord is between the two belt plies. They are arranged to cross each other in opposite directions. Steel is exemplified as the material of the cord.

  The carcass layer 4 is composed of at least one (in this embodiment, one) carcass ply, and the pair of annular bead cores 1a are wound up and locked from the inner side in the width direction to the outer side. In the present embodiment, the winding end 4E of the carcass layer 4 is disposed outside the tire radial direction outer end 1bEout of the bead filler 1b. However, in the present invention, the winding end 4E of the carcass layer 4 may be disposed at the same height position as the tire radial direction outer end 1bEout of the bead filler 1b, or from the tire radial direction outer end 1bEout of the bead filler 1b. May also be placed inside.

  The carcass ply constituting the carcass layer 4 is formed by rubber-covering a cord extending at an angle of about 90 ° with respect to the tire equator line C. As the carcass ply, those formed by coating an organic fiber cord such as polyester, rayon, nylon, or aramid with rubber are preferably used.

  As shown in FIG. 2 in an enlarged manner, in the present embodiment, the outer reinforcing layer 6out that covers the rolled-up end 4E of the carcass layer 4 from the outer side in the tire width direction is provided, and the outer reinforcing layer 6out substantially covers the PEN film in the circumferential direction. It is formed by winding along a spiral. The outer reinforcing layer 6out only needs to be configured to cover at least the winding end 4E of the carcass layer 4 from the outer side in the tire width direction. In this embodiment, the outer reinforcing layer 6out is 15 mm on the outer circumferential side (outer in the tire radial direction) than the winding end 4E of the carcass layer 4 ) To the same height as the inner end of the bead filler 1b in the tire radial direction. In the present invention, “substantially along the circumferential direction” means within 5 ° with respect to the tire circumferential direction (tire equator line C) in addition to the case of extending along the tire circumferential direction (tire equator line C). Including the case of extending at an angle of.

  PEN is composed of a polymer containing 85 mol% or more, preferably 90 mol% or more of ethylene-2,6-naphthalate. This polymer is synthesized according to a known method, for example, a method described in JP-A-5-163612. can do.

  The PEN film may be prepared, for example, by cutting a sheet film having a predetermined thickness by a normal film casting method obtained by extruding a PEN molten resin or by a biaxial stretching method into a thin width. it can. The thickness of the PEN film is preferably 0.05 to 0.5 mm, and more preferably 0.05 to 0.2 mm. The width of the PEN film is preferably 1 to 10 mm, and more preferably 1.7 to 2 mm.

  The tensile modulus (modulus) is preferably in the range of 10 to 200 GPa, more preferably 30 to 100 GPa. The tensile elastic modulus is a value measured at room temperature in accordance with the method defined in JIS K7127.

  If the modulus of the tape 10 is less than 10 GPa, it is difficult to obtain sufficient tension and rigidity in the tire circumferential direction, and durability and handling stability cannot be satisfied. To ensure rigidity, the amount of use increases, the tire weight increases, and the cost increases. May increase. On the other hand, if it exceeds 200 GPa, the tape becomes too rigid and tends to cause separation due to a difference in modulus from rubber.

  In addition, the PEN film is used for a normal tire cord adhesion treatment, for example, a treatment mainly composed of resorcin-formalin-rubber latex (RFL) or an epoxy-based film in order to improve adhesion to rubber. It is preferable to perform a surface treatment using a treatment agent containing an adhesive.

  As a method of winding a PEN film substantially spirally along the circumferential direction of the tire, the spiral of the carcass layer 4 is performed while shifting the adjacent films to each other in the width direction while stacking adjacent films. There are a method of winding a film in a shape, or a method of winding a film in a spiral shape while shifting adjacent films at predetermined intervals. In these methods, the thickness of the outer reinforcing layer 6out and the cross-sectional shape in the tire width direction can be set to arbitrary shapes by adjusting the setting of the overlap margin when the film is wound in a spiral shape.

  In the present embodiment, the thickness of the outer reinforcing layer 6out in the vicinity of the winding end 4E of the carcass layer 4 is larger than the thickness of the other part of the outer reinforcing layer 6out. A portion where the thickness of the outer reinforcement layer 6out is large (portion in the vicinity of the winding end 4E of the carcass layer 4) is wound (closely wound) in a spiral shape while increasing the overlap between adjacent PEN films. It is formed by. As a result, the reinforcing effect of the outer reinforcing layer 6out is further enhanced in the vicinity of the wound end 4E of the carcass 4 layer, so that separation based on the vicinity of the wound end 4E of the carcass layer 4 can be more reliably prevented.

  In the present embodiment, the outer reinforcing layer 6out other than the vicinity of the winding end 4E of the carcass layer 4 is spirally packed with adjacent PEN films (the overlap margin is 0 and the interval is 0). ). Thereby, since the longitudinal rigidity at the time of running of the tire can be appropriately reduced, it is possible to improve riding comfort in addition to durability. In the present invention, the adjacent PEN films are wound spirally while reducing the overlap margin between adjacent PEN films, or the adjacent PEN films are wound spirally while shifting with a predetermined interval between them. By doing so, the outer reinforcing layer 6out can be formed.

  2, in this embodiment, in addition to the outer reinforcing layer 6out, the carcass layer 4 is disposed on the inner side in the width direction of the winding end 4E and on the outer side in the width direction of the bead filler 1b. An inner reinforcing layer 6in that covers the end 4E is further provided. Since the winding end 4E of the carcass layer 4 is covered from the inner side in the width direction by the inner reinforcing layer 6in, separation based on the vicinity of the winding end 4E of the carcass layer 4 can be further reliably prevented.

  In this embodiment, adjacent PEN films are packed together and spirally wound (the overlap margin is 0 and the interval is also 0) to form the inner reinforcing layer 6in, in the vicinity of the winding end 4E of the carcass layer 4 The thickness of the outer reinforcing layer 6out is larger than the thickness of the inner reinforcing layer 6in. In this case, while maintaining the reinforcing effect of the inner reinforcing layer 6in, the longitudinal rigidity during running of the tire can be appropriately reduced, so that the durability and steering stability of the tire and the riding comfort are improved in a well-balanced manner. be able to.

  The pneumatic tire of the present invention is the same as a normal pneumatic tire except that the outer reinforcing layer and / or the inner reinforcing layer is configured as described above, and any conventionally known material, shape, structure, manufacturing method, etc. Can also be employed in the present invention.

[Other Embodiments]
In the above-described embodiment, an example in which a PEN film is used as the resin film constituting the outer reinforcing layer 6out and the inner reinforcing layer 6in has been described. However, in the present invention, other resin films than the PEN film, for example, polyamide resins such as nylon 66; polyester resins such as polyethylene terephthalate (PET); polyvinyl resins such as polyvinyl alcohol (PVA) can be used. It is.

  In the above-described embodiment, an example in which the inner reinforcing layer 6in is further provided in addition to the outer reinforcing layer 6out has been described. However, as illustrated in an enlarged view in FIG. 3, only the outer reinforcing layer 6out may be provided. In this embodiment, the outer reinforcing layer 6out is formed by packing adjacent PEN films and spirally winding them (the overlap margin is 0 and the interval is also 0), and from the winding end 4E of the carcass layer 4 Also extends from the outer position in the tire radial direction to a height position near the outer end 1bEout in the tire radial direction of the bead filler 1b. When only the outer reinforcing layer 6out is provided and the inner reinforcing layer 6in is not provided, the effect of improving durability and steering stability is slightly reduced, but riding comfort is particularly improved.

  In the above-described embodiment, an example in which the inner reinforcing layer 6in is formed by packing adjacent PEN films and winding them spirally (with an overlap margin of 0 and an interval of 0) has been described. However, in the present invention, as shown in FIGS. 4 and 5 in an enlarged manner, the inner reinforcing layer 6in may be formed of a rubber-coated PEN film that is rubber-coated with a space between the PEN films. FIG. 6 shows an enlarged inner reinforcing layer 6in made of a rubber-coated PEN film. In FIG. 6, 7 indicates a PEN film, and 8 indicates a coated rubber. In FIG. 4, the inner end in the tire radial direction of the outer reinforcing layer 6out is arranged in the vicinity of the outer end 1bEout in the tire radial direction of the bead filler 1b, and the inner radial end of the inner reinforcing layer 6in is set in the tire radial direction of the bead filler 1b. An example is shown in the vicinity of the outer end 1bEout. In FIG. 5, the inner end in the tire radial direction of the outer reinforcing layer 6out is arranged in the vicinity of the outer end 1bEout in the tire radial direction of the bead filler 1b, and the inner end in the tire radial direction of the inner reinforcing layer 6in is the tire of the bead filler 1b. An example is shown in the vicinity of the radially inner end 1bEin.

  The rubber-coated PEN film, which has been previously covered with the PEN film with a space therebetween, has a higher rubber adhesion to the carcass layer 4 and other members in contact with the inner reinforcing layer 6in. For this reason, the separation of the winding end 4E of the carcass layer 4 can be more reliably prevented. Moreover, since the PEN films are arranged in a state of being spaced apart in the rubber-coated PEN film, it is possible to moderate moderately the increase in longitudinal rigidity during tire travel. As a result, the riding comfort of the tire can be improved. In addition, in order to improve durability, handling stability, and riding comfort in a well-balanced manner, the distance D between adjacent PEN films is set to 0.5 W ≦ D ≦ 5 W with respect to the width W of the PEN film. It is preferable that

  Examples that specifically show the structure and effects of the present invention will be described below. Evaluation items in Examples and the like were measured as follows.

(1) High-speed durability A test was conducted in accordance with the conditions for a tire with a speed symbol W defined as a load / speed performance test procedure in Appendix 7 of the European Economic Commission Regulation 30. The running speed was increased by 10 km / h every 10 minutes, and was run at high speed with a drum tester until the tire broke down. The result of Comparative Example 1 was evaluated as an index with the value of 100, and the higher the index, the better the high-speed durability.

(2) Steering stability Four panelists conducted a comprehensive sensory evaluation on starting, turning and braking on the test course. The result of Comparative Example 1 was evaluated as an index with the value 100, and the larger the index, the better the steering stability.

(3) Ride comfort Four panelists comprehensively evaluated the ride comfort on the test course. The result of Comparative Example 1 was evaluated as an index with the value of 100, and the larger the index, the better the riding comfort.

Example 1
The outer reinforcing layer 6out shown in FIG. 2 is formed by spirally winding a PEN film along the circumferential direction, and the thickness of the carcass layer 4 near the winding end 4E is 0.5 mm. The thickness of the carcass layer 4 other than the vicinity of the winding end 4E is 0.2 mm) and the inner reinforcing layer 6in (adjacent PEN films are packed together and spirally wound (the overlap margin is 0 and the interval is also 0) A pneumatic tire having a thickness of 0.2 mm) was defined as Example 1. Table 1 shows the measurement results of the evaluation items.

Example 2
Air provided with an outer reinforcing layer 6out shown in FIG. 3 (formed by spirally winding a PEN film substantially in the circumferential direction and having a thickness of 0.5 mm and substantially constant in each part). Example 2 was used as the entering tire. Table 1 shows the measurement results of the evaluation items.

Example 3
The outer reinforcing layer 6out shown in FIG. 4 (formed by spirally winding a PEN film along the circumferential direction, the thickness is 0.5 mm, and each part is substantially constant) and the inner reinforcing layer 6 inch (formed by a rubber-coated PEN film (rubber-coated PEN film shown in FIG. 6) coated with rubber with a space between PEN films, the thickness is 0.3 mm, and each part is substantially constant. PEN A pneumatic tire provided with an interval D between adjacent PEN films with respect to the width W of the film was D = W). Table 1 shows the measurement results of the evaluation items.

Example 4
Outer reinforcing layer 6out shown in FIG. 5 (formed by spirally winding a PEN film along the circumferential direction, the thickness is 0.5 mm, and each part is substantially constant) and the inner reinforcing layer 6 inch (formed by a rubber-coated PEN film (rubber-coated PEN film shown in FIG. 6) coated with rubber with a space between PEN films, the thickness is 0.3 mm, and each part is substantially constant. PEN A pneumatic tire provided with a distance D between adjacent PEN films with respect to the width W of the film was D = W). Table 1 shows the measurement results of the evaluation items.

Comparative example 1 (conventional example)
The outer reinforcement layer 6out has the same configuration as that of Example 2 except that the steel cord having an inclination angle in the range of 80 to 100 ° with respect to the radial direction of the tire is changed to a reinforcement cord layer formed by rubber coating. The provided pneumatic tire was set as Comparative Example 1. Table 1 shows the measurement results of the evaluation items.

Comparative Example 2
Except that the outer reinforcing layer 6out is changed to a reinforcing cord layer formed by rubber-covering a PEN cord having an inclination angle within a range of 80 to 100 ° with respect to the radial direction of the tire, the same configuration as that of Example 2 is adopted. The provided pneumatic tire was designated as Comparative Example 2. Table 1 shows the measurement results of the evaluation items.

Comparative Example 3
Example except that the outer reinforcement layer 6out and the inner reinforcement layer 6in were changed to a reinforcement cord layer formed by rubber-covering a PEN cord having an inclination angle within a range of 80 to 100 ° with respect to the radial direction of the tire. A pneumatic tire having the same configuration as that of No. 3 was used as Comparative Example 3. Table 1 shows the measurement results of the evaluation items.

  From the results in Table 1, it can be seen that the durability, steering stability and riding comfort of the tires are improved in a well-balanced manner in the pneumatic tires of Examples 1 to 4 as compared with Comparative Example 1 (conventional example). . In particular, in Example 1, the thickness of the outer reinforcing layer 6out in the vicinity of the rolled-up end 4E of the carcass layer 4 is larger than that of other portions of the outer reinforcing layer 6out and the inner reinforcing layer 6in, so that riding comfort is maintained. However, durability and handling stability are further improved. Moreover, in Example 2, since the inner reinforcement layer is not provided, riding comfort is particularly improved while maintaining durability and steering stability. Furthermore, in Example 3 and Example 4, durability, steering stability, and riding comfort are particularly well-balanced.

  On the other hand, in the pneumatic tires (Comparative Examples 2 and 3) including the reinforcing cord layer formed by covering the PEN cord with rubber instead of the outer reinforcing layer and the inner reinforcing layer made of the PEN film, the steering stability deteriorated. .

1: Bead part 1a: Annular bead core 1b: Bead filler 2: Side wall part 3: Tread part 4: Carcass layer 4E: Winding end of carcass layer 5: Belt layer 6out: Outer reinforcing layer 6in: Inner reinforcing layer

Claims (7)

In a pneumatic tire comprising a pair of annular bead cores, a bead filler disposed on the outer peripheral side of the beat core, and a carcass layer whose end side is wound up from the inner side in the width direction in the bead core,
An outer reinforcing layer that is disposed on the outer side in the width direction of the winding end of the carcass layer and covers at least the winding end of the carcass layer;
The outer reinforcing layer is formed by spirally winding the resin film substantially along the circumferential direction ,
The pneumatic tire according to claim 1, wherein a thickness of the outer reinforcing layer in the vicinity of a rolled-up end of the carcass layer is larger than a thickness of other portions of the outer reinforcing layer .   The pneumatic tire according to claim 1, wherein the resin film constituting the outer reinforcing layer is a polyethylene naphthalate film. An inner reinforcing layer that is disposed on the inner side in the width direction of the winding end of the carcass layer and on the outer side in the width direction of the bead filler, and covers at least the winding end of the carcass layer;
The inner reinforcement layer, the pneumatic tire according to claim 1 or 2 including a plurality of resin film extending substantially in the circumferential direction. The pneumatic tire according to claim 3 , wherein a thickness of the outer reinforcing layer in the vicinity of a winding end of the carcass layer is larger than a thickness of the inner reinforcing layer. The pneumatic tire according to claim 3 or 4 , wherein a plurality of the resin films included in the inner reinforcing layer are arranged with a space therebetween. The pneumatic tire according to any one of claims 3 to 5 , wherein the resin film constituting the inner reinforcing layer is a polyethylene naphthalate film. The pneumatic tire according to any one of claims 3 to 6 , wherein the resin film constituting the inner reinforcing layer is a rubber-coated resin film obtained by rubber-coating a resin film.

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