AIR TIRES AND METHOD FOR THEIR MANUFACTURE

Abstract

A pneumatic tire is provided which has sufficient tire thickness in a shoulder section and provides durability and puncture sealing properties of the tire in a compatible manner by providing a carcass structure, and a method for its manufacture.In a pneumatic tire having a structure in which a carcass layer (4) is folded around a bead core (5) of each of bead sections (3) from an inside to an outside of the tire, an end (4e) of a folded section (4B) of the carcass layer (4) is arranged on an inside in the tire width direction relative to an end section (7e) of a belt layer (7), a sealant layer (20) is formed on an inner tire surface (10) in a tread section (1), and an end section (20e) of the sealant layer (20) is located in the tire width direction in the shoulder section and is arranged on an outside in the tire width direction relative to the end (4e) of the folded section (4B) of the carcass layer (4).

Description

Technical field

[0001] The present invention relates to a pneumatic tire which includes a sealing layer on an inner tire surface in a tread section, and a method for its manufacture, and in particular relates to a pneumatic tire which has a sufficient tire thickness in a shoulder section and exhibits the durability and puncture sealing properties of the tire in a compatible manner by providing a carcass structure, and a method for its manufacture. State of the art

[0002] A pneumatic tire with puncture-sealing properties has been proposed in which a sealant layer formed from an adhesive sealant is arranged on an inner surface of the tire in a tread section (for example, patent document 1). In a pneumatic tire provided with such a sealant layer, when a foreign object such as a nail penetrates the tread section, the adhesive sealant is captured by the foreign object, and the adhesive sealant is guided to a puncture hole when the foreign object falls off, thereby achieving a sealing effect.

[0003] However, if the sealant layer is located on the inner surface of the tire, the tire weight increases, and consequently, so does the centrifugal force during driving. This tends to worsen the tire's durability, and in particular, a failure is likely to occur in the shoulder section, which has a thinner tire. List of oppositions patent literature

[0004] Patent Document 1: JP 2003-080909 A Brief description of the invention: Technical problem

[0005] One object of the present invention is to provide a pneumatic tire which has sufficient tire thickness in a shoulder section and provides durability and puncture sealing properties of the tire in a compatible manner by providing a carcass structure, and a method for manufacturing the pneumatic tire. Solution to the problem

[0006] To achieve the above-described objective, a pneumatic tire according to an embodiment of the present invention includes: a tread section extending in a tire circumferential direction and having a ring shape; a pair of sidewall sections arranged on both sides of the tread section; a pair of bead sections, each arranged in the tire radial direction on inner sides of the sidewall sections; at least one carcass layer mounted between the pair of bead sections; and a belt layer arranged on an outer circumferential side of the carcass layer in the tread section, wherein the carcass layer is folded around a bead core of each of the bead sections from an inner to an outer side of the tire.In the pneumatic tire, one end of a folded-over section of the carcass layer is arranged on an inner side in the tire width direction relative to an end section of the belt layer, a sealant layer is formed on an inner tire surface in the tread section, and an end section of the sealant layer in a tire width direction is located in a shoulder section and is arranged on an outer side in the tire width direction relative to the end of the folded-over section of the carcass layer.

[0007] To achieve the above-described objective, a method for manufacturing a pneumatic tire according to one embodiment of the present invention is a method for manufacturing the pneumatic tire described above. The method includes: manufacturing a pneumatic tire excluding the sealant layer; and then, when forming the sealant layer by applying sealant to the inner surface of the tire in the tread area, setting the temperature of the sealant to be applied to the inner surface of the tire to 70 °C or less. Advantageous effects of the invention

[0008] In one embodiment of the present invention, in the pneumatic tire that encloses the carcass layer folded around the bead core of each bead section from the inside to the outside of the tire, the end of the folded section of the carcass layer is arranged on the inside in the tire width direction relative to the end section of the belt layer, thereby making it possible to increase the number of elements in the shoulder section. As a result, the tire thickness in the shoulder section can be increased, the tire's durability can be improved, and the amount of air leakage in the shoulder section can be reduced, even if a nail penetrates and then emerges from the shoulder section.Under this type of carcass structure, the end section of the sealant layer is located in the shoulder area, in the direction of the tire's width, and is positioned on the outside, in the direction of the tire's width, relative to the end of the folded-over section of the carcass layer. Therefore, the tire puncture sealing properties in the shoulder area can be adequately ensured without taking any measures to increase the thickness of the sealant layer. This ensures sufficient tire thickness in the shoulder area and provides tire durability and puncture sealing properties in a compatible manner.

[0009] The pneumatic tire according to one embodiment of the present invention preferably includes a belt cover layer on an outer circumferential side of the belt layer, and the belt cover layer is preferably arranged such that it covers at least the end section of the belt layer in the tire width direction. This can further improve tire durability and can also reduce the amount of air leakage from a shoulder section, even if a nail penetrates the tire, thereby further improving the tire's puncture sealing properties.

[0010] The sealant layer preferably has a thickness in the range of 2.0 mm to 5.0 mm. This ensures sufficient tire puncture sealing properties in both the central and shoulder sections.

[0011] The sealant forming the sealant layer preferably has a glass transition temperature in the range of -120 °C to -40 °C. Using a sealant with a low glass transition temperature can ensure satisfactory tire puncture sealing properties in low-temperature environments.

[0012] The sealant forming the sealant layer is preferably composed of a silicone-based material. This allows the sealant layer to adhere well to the inner tire surface, even if a separating agent is present on the inner tire surface, since the sealant layer is made of the same material.

[0013] The silicone-based composition is preferably a two-part curable silicone. Since the two-part curable silicone has a low viscosity immediately after mixing the two components, it can also be applied at low temperatures.

[0014] At all points of a belt layer positioned on the innermost side in the tire radial direction, the distance L from the belt layer to the sealant layer is preferably 10 mm or less. This allows the sealant to flow easily into the belt layers if a foreign object, such as a nail, penetrates the tread section, thus ensuring good tire puncture sealing properties.

[0015] A sound-absorbing element is preferably arranged along the tire's circumferential direction on an inner surface of the sealant layer in the tire's radial direction. This allows the sound-absorbing element to be positioned relative to the sealant layer. Brief description of the drawings Fig. Figure 1 is a meridian cross-sectional view illustrating a pneumatic tire according to an embodiment of the present invention. Fig.Figure 2 is a cross-sectional view showing a major part of the pneumatic tire. Fig. 1 illustrates. Fig. Figure 3 is a cross-sectional view illustrating an example of a method for manufacturing the pneumatic tire according to the embodiment of the present invention. Fig. 4 is a top view showing a view of the inner surface of a tire in a tread section of the pneumatic tire. Fig. 3. Formed sealant layer illustrated. Fig. Figure 5 is a cross-sectional view illustrating a main section of a pneumatic tire according to a further embodiment of the present invention. Fig. Figure 6 is a meridian cross-sectional view illustrating a pneumatic tire according to a further embodiment of the present invention. Fig. Figure 7 is a meridian cross-sectional view illustrating an air tire that has a conventional carcass structure. Description of embodiments

[0016] Configurations of embodiments of the present invention are described in detail below with reference to the accompanying drawings. Fig. 1 and Fig. Figure 2 illustrates a pneumatic tire according to an embodiment of the present invention.

[0017] As in Fig. As illustrated in Figure 1, the pneumatic tire according to the present embodiment includes a tread section 1 extending in the circumferential direction of the tire and having a ring shape, a pair of sidewall sections 2 arranged on both sides of the tread section 1, and a pair of bead sections 3 arranged on the inner sides of the pair of sidewall sections 2 in the radial direction of the tire.

[0018] At least one carcass layer 4 (one layer in Fig.1), which is formed by arranging a plurality of carcass cord threads in a radial direction, is mounted between the pair of bead sections 3. Organic fiber cord threads made of nylon and polyester are preferably used as the carcass cord threads forming the carcass layer 4. Bead cores 5, which have a ring shape, are embedded in the bead sections 3, and bead fillers 6, which are made of a rubber compound and have a triangular cross-section, are arranged on the outer circumferences of the bead cores 5.

[0019] On the other hand, a plurality of belt layers 7 (two layers in Fig.1) embedded on the outer circumference of the carcass layer 4 of the tread section 1. The belt layers 7 enclose a plurality of reinforcing cord threads inclined with respect to the tire's circumferential direction, and the reinforcing cord threads are arranged between layers such that they overlap. The angle of inclination of the reinforcing cords in the belt layers 7 with respect to the tire's circumferential direction is specified such that it falls within a range of, for example, 10° to 40°. Steel cords are preferably used as the reinforcing cords of the belt layers 7.

[0020] To improve durability at high speeds, at least one belt cover layer 8 (two layers in Fig.1), which is formed by arranging reinforcing cord threads at an angle of, for example, 5° or less with respect to the tire's circumferential direction, is arranged on an outer circumferential side of the belt layers 7. The belt cover layer 8 preferably has a seamless structure in which a strip material made of at least one single reinforcing cord, laid out and covered with rubber, is continuously wound at an angle of substantially 0° with respect to the tire's circumferential direction. Organic fiber cords such as nylon and aramid are preferably used as reinforcing cords of the belt cover layer 8.

[0021] In the pneumatic tire described above, both ends 4e of the carcass layer 4 are folded back from the inside to the outside of the tire around each of the bead cores 5 and are arranged such that they wrap around the bead cores 5 and the bead fillers 6. The carcass layer 4 includes a body section 4A, which is a section extending from the tread section 1 through each sidewall section 2 to each bead section 3, and a folded section 4B, which is a section folded around the bead core 5 in each bead section 3 and extends to each side of the sidewall section 2. The end 4e of the folded section 4B of the carcass layer 4 is arranged between the body section 4A of the carcass layer 4 and the belt layers 7.This means that the end 4e of the folded-over section 4B of the carcass layer 4 is arranged on the inside in the tire width direction relative to an end section 7e of the belt layer 7.

[0022] The preceding description illustrates an example of a pneumatic tire having one carcass layer. Without limiting itself to this example, the pneumatic tire can have two carcass layers. In this case, in the sidewall section 2, the end 4e of the folded-over section 4B of the carcass layer 4, located on the outermost side in the tire width direction, can be positioned between the body section 4A of the carcass layer 4 and the belt layers 7.

[0023] In the pneumatic tire described above, a continuous sealant layer 20 is formed on an inner surface 10 of the tire in the tread section 1. The center position of the sealant layer 20 in the tire width direction preferably coincides with the tire equator, but this center position can be shifted from the tire equator to any side in the tire width direction. The distance in the tire width direction between the center position of the sealant layer 20 in the tire width direction and the tire equator is preferably 10 mm or less, and more preferably 5 mm or less. This ensures that the sealant layer 20 does not adversely affect the tire's balance. The sealant forming the sealant layer 20 can, for example, consist of a diene rubber or a silicone-based composition.In particular, the sealant is preferably composed of a silicone-based composition, and the silicone-based composition preferably includes a synthetic polymer compound having a main chain formed by a siloxane bond. An end section 20e in the tire width direction of the sealant layer 20 is located in a shoulder section Sh and is arranged on the outside in the tire width direction relative to the end 4e of the folded section 4B of the carcass layer 4. In this case, the shoulder section Sh refers to a region of 20 mm on both sides in the radial direction from a perpendicular line x drawn from the end section 7e of the belt layer 7, which is located on the innermost side in the tire radial direction, to the inner tire surface 10.

[0024] In the pneumatic tire described above, the end 4e of the folded section 4B of the carcass layer 4 is located on the inside in the tire width direction relative to the end section 7e of the belt layer 7, thereby increasing the number of elements in the shoulder section Sh. As a result, the tire thickness in the shoulder section Sh can be increased, the tire's durability can be improved, and the amount of air leakage in the shoulder section Sh can be reduced, even if a nail penetrates and then exits the shoulder section Sh. Under such a carcass structure, the end section 20e of the sealant layer 20 is located in the tire width direction within the shoulder section Sh and is positioned on the outside in the tire width direction relative to the end 4e of the folded section 4B of the carcass layer 4.Therefore, the tire puncture sealing properties in the shoulder section Sh can be adequately ensured without taking any measures to increase the thickness of the sealant layer 20. This ensures sufficient tire thickness in the shoulder section Sh and provides tire durability and tire puncture sealing properties in a compatible manner.

[0025] In contrast, as in Fig. Figure 7 illustrates that in a pneumatic tire having a conventional carcass structure, where the end 4e of the folded-over section 4B of the carcass layer 4 is located in the middle of the sidewall section 2, when a sealant layer is arranged on the inner surface of the tire, the number of elements in the shoulder section is low, and thus the tire durability is likely to deteriorate. Since one embodiment of the present invention involves the Fig.As illustrated in Figure 1, the number of elements in the shoulder section (Sh) can be increased. This can improve tire durability and reduce the amount of air leakage in the shoulder section (Sh), even if the nail penetrates and then exits the shoulder section (Sh).

[0026] In the case of the pneumatic tire, the glass transition temperature of the sealant in the sealant layer 20 is preferably in the range of -120 °C to -40 °C. The use of a sealant with a low glass transition temperature can ensure satisfactory tire puncture sealing properties in a low-temperature environment. If the glass transition temperature of the sealant is higher than -40 °C, the tire puncture sealing properties deteriorate in a low-temperature environment.

[0027] The pneumatic tire described above can be manufactured using the following method. First, a pneumatic tire is manufactured as described above, comprising the tread section 1, the pair of sidewall sections 2, the pair of bead sections 3, the carcass layer 4, and the belt layers 7, in which the ends 4e of the folded-over section 4B of the carcass layer 4 are arranged on the inside in the tire width direction relative to the end sections 7e of the belt layers 7. Next, the sealant layer 20 is formed by applying a sealant made of a diene rubber or a silicone-based composition to the inner surface 10 of the tire in the tread section 1.At this point, the end section 20e of the sealant layer 20 is located in the shoulder section Sh and on the outside in the tire width direction relative to the end 4e of the folded section 4B of the carcass layer 4. In a case where a silicone-based composition is used, since the silicone-based composition has good flowability even at low temperatures, the temperature of the sealant to be applied to the inner tire surface 10 is set to 70 °C or less. If the temperature is above 70 °C, the distortion created in the pneumatic tire during the process of applying the sealant to the inner tire surface 10 increases, and the tire durability deteriorates.In particular, the temperature of the sealant when applied to the inner tire surface 10 is preferably in the range of 5 °C to 40 °C, more preferably in the range of 10 °C to 35 °C, and most preferably in the range of 15 °C to 30 °C. Adjusting the temperature of the sealant accordingly in this way suppresses overvulcanization in the shoulder section Sh due to heating during the formation of the sealant layer 20. If the inner tire surface 10 contains a release agent, the same material is used. Therefore, the sealant layer 20 can adhere satisfactorily to the inner tire surface 10.

[0028] Fig. Figure 3 illustrates a specific method for manufacturing a pneumatic tire according to the embodiment of the present invention. Fig. Figure 4 illustrates the sealant layer that forms on the inner surface of the tire in the tread section. Fig.3 A sealant extrusion device 31 mixes the sealant supplied from pumps 32 and 33 and continuously dispenses the mixed sealant from a nozzle 34 as strip material 21. The sealant extrusion device 31 is configured to shift the position of the nozzle 34. Therefore, by moving the nozzle 34 in the tire axial direction during tire rotation from a state in which the nozzle 34 is brought close to the inner tire surface 10, the strip material 21 of sealant can be arranged spirally on the inner tire surface 10 while inclined with respect to a tire circumferential direction Tc (see Fig. 4) The spirally arranged sealant strip 21 has circumferential sections in close contact with each other. Thus, the spirally arranged sealant strip 21 is integrated into the sealant layer 20.

[0029] The silicone-based composition forming the sealant of the sealant layer 20 can be either a one-component or a two-component curable silicone, but the use of a two-component curable silicone is particularly preferred. Examples of one-component curable silicone include, for instance, moisture-curable silicone. The two-component curable silicone consists of a first liquid and a second liquid. A curing reaction is initiated by mixing the first and second liquids, thereby ensuring stability as a sealant layer 20 after curing. In the apparatus described above, the first and second liquids of the two-component curable silicone are supplied from pumps 32 and 33, respectively.Since the two-part curable silicone has a low viscosity immediately after the two parts are mixed, it can also be applied at low temperatures.

[0030] The two-part curable silicone consists of, for example, a condensation-curable silyl-terminal polymer, a silane crosslinking agent, a condensation catalyst, a filler, and the like. Examples of the condensation-curable silyl-terminal polymer include polydialkylsiloxane, alkylphenylsiloxane, organic polymers containing a silyl group (e.g., silyl polyether, silyl acrylate), and polyisobutylene containing a silyl group. Examples of the silane crosslinking agent include alkoxy-functional silanes, oximosilanes, acetoxysilanes, and enoxysilanes. Examples of the filler include iron oxide, titanium dioxide, carbon black, and talc. Examples of the condensation catalyst include titanates and zirconates.The condensation-curable silyl-terminal polymer, the silane crosslinking agent, the condensation catalyst, and the filler are stored in a state where they are separated into the first liquid and the second liquid in a combination in which a curing reaction does not proceed, and are mixed at the time of use. Examples of two-part curable silicone include those described in JP 2018-503725 B and JP 2022-550962 B. For example, Dow's SST-2650 can be used as a commercially available two-part curable silicone product.

[0031] In the pneumatic tire described above, the belt cover layer 8 may cover only a portion of the belt layers 7 in the tire width direction (for example, edge sections on both sides of the belt layers in the tire width direction), but may also cover the entire region of the belt layers 7 in the tire width direction. This can further improve the tire's durability and reduce the amount of air leakage from a shoulder section Sh, even if a nail penetrates the tire, thereby further improving the tire's puncture sealing properties. In the embodiment of Fig. 1 The belt cover layer 8, located on the inside in the tire radial direction, forms a complete cover that covers all the belt layers 7, and the belt cover layer 8, located on an outside in the tire radial direction, forms an edge cover that only covers edge sections of the belt layers 7.

[0032] In the pneumatic tire described above, the sealant layer 20 preferably has a thickness S (see Fig.2) in the range of 2.0 mm to 5.0 mm. This ensures sufficient tire puncture sealing properties in both the center section and the shoulder section Sh. If the thickness S of the sealant layer 20 is less than 2.0 mm, the tire puncture sealing properties are reduced, and conversely, if the thickness S is greater than 5.0 mm, the sealant layer 20 flows due to the centrifugal forces of the tire, and the tire's balance during driving deteriorates. The thickness S of the sealant layer 20 is the overall average thickness.The average thickness of such a sealant layer 20 can be calculated by, for example, taking CT scans of a tire meridian cross-section at eight sections on the tire circumference and measuring the thickness of the sealant layer 20 at five points in each of the recorded images: the tire equator position, outer edge positions (on both sides) 10 mm inwards in the tire width direction of edge sections 20e of the sealant layer 20 and intermediate positions (on both sides) between the tire equator position and the outer edge positions from the measured values ​​at a total of 40 points.

[0033] The pneumatic tire described above is, as in Fig.Figure 2 illustrates a distance (shortest distance) L from the belt layers 7 to the sealant layer 20, preferably 10 mm or less, at all points on the belt layer 7 that are positioned on the innermost side in the tire radial direction. This allows the sealant to flow easily to the belt layers 7 if a foreign object, such as a nail, penetrates the tread section 1, thus ensuring good puncture sealing properties. If there is a section where the length L from the belt layers 7 to the sealant layer 20 is greater than 10 mm, the puncture sealing properties in that section may be inadequate.

[0034] Fig. Figure 5 illustrates a pneumatic tire according to another embodiment of the present invention. Fig.In section 5, the end section 20e of the sealant layer 20 is located in the shoulder section Sh and is positioned between the end 4e of the folded-over section 4B of the carcass layer 4 and the end section 7e of the belt layer 7. In this case, by minimizing the area where the sealant layer 20 is located on the inner surface 10 of the tire, an increase in tire weight is suppressed and adverse effects on tire durability are avoided.

[0035] Fig. Figure 6 illustrates a pneumatic tire according to a further embodiment of the present invention. Fig.6 A sound-absorbing element 40 is arranged along the tire's circumferential direction on the inside of the sealant layer 20 in the tire's radial direction. The sound-absorbing element 40 is made of a porous, open-cell material and exhibits predefined sound absorption properties based on its porous structure. Preferably, polyurethane foam is used as the porous material of the sound-absorbing element 40. The sound-absorbing element 40 is applied to the sealant layer 20 based on the adhesion of the sealant layer 20 after the sealant layer 20 has formed.In a case where a silicone-based composition is used as a sealant forming the sealant layer 20, damage to the sound-absorbing element 40 can be avoided, and its sound absorption effect can be satisfactorily maintained, since the sound-absorbing element 40 is arranged on the sealant layer 20 applied at low temperature. Examples

[0036] Tires according to the prior art example and Examples 1 to 8 were manufactured. The tires have a tire size of 255 / 45R19 and include: the tread section, which extends in the circumferential direction of the tire and has a ring shape; the pair of sidewall sections arranged on both sides of the tread section; the pair of bead sections, each arranged on the inside of the sidewall section in the radial direction of the tire; at least one carcass layer mounted between the pair of bead sections; and the belt layer, which is arranged on the outer circumferential side of the carcass layer in the tread section, the carcass layer being folded around a bead core of each of the bead sections from the inside to the outside of the tire.In each tire, the sealant layer is formed on the inner surface of the tire in the tread section, and the structure of the carcass layer, the structure of the belt cover layer, the thickness of the sealant layer, the type of sealant and the distance L were specified as shown in Table 1.

[0037] In Table 1, under the “Structure of the Belt Layer”, “End Section Only” means the structure including an edge cover that covers only edge sections on both sides in the tire width direction of the belt layer, and “Entire Region” means the structure including a complete cover that covers the entire region in the tire width direction of the belt layer.

[0038] Durability, puncture sealing properties, and ride comfort were evaluated for each of the test tires according to the following test procedures. The results are also shown in Table 1. Resistance:

[0039] Each test tire was mounted on a wheel with a rim size of 19 × 8.5J, and a road test was performed using a drum tire testing machine at an air pressure of 120 kPa, 100% of the maximum load, and a driving speed of 80 km / h. After the test, the distance traveled until tire failure was measured. Evaluation results are expressed as index values, with the state-of-the-art example value defined as 100. Higher index values ​​indicate superior durability. Tire puncture sealing properties:

[0040] Each test tire was mounted on a wheel with a rim size of 19 × 8.5J, and a 4 mm diameter nail was inserted into the shoulder section under conditions of an initial air pressure of 250 kPa and a temperature of 23 °C. After the nail was removed, the tire was left for two weeks, and the air pressure was measured. The evaluation results are expressed as index values ​​using the reciprocals of the measured values, where the prior art example value is defined as 100. Higher index values ​​indicate superior tire puncture sealing properties. Driving comfort:

[0041] Each test tire was mounted on a 19 × 8.5J rim and inflated to 230 kPa on a front-wheel-drive vehicle. Sensory evaluations were performed by a test driver on a test track, including a circuit on a smooth road surface. Evaluation results are expressed as index values, with 100 representing the state of the art. Higher index values ​​indicate greater ride comfort. An index value of 98 or higher means that ride comfort is maintained at the state of the art level. [Table 1-I] Example of the state of the art Example 1 Example 2 Structure of the carcass layer Fig. 7 Fig. 1 Fig. 1 Structure of the belt cover layer End section only End section only Entire region Sealant layer thickness (mm) 1,0 1,0 1,0 Type of sealant Dien rubber Dien rubber Dien rubber Distance L (mm) 11 11 11 resistance 100 105 107 Tire puncture sealing properties 100 102 104 Driving comfort 100 100 100 [Table 1-II] Example 3 Example 4 Example 5 Structure of the carcass layer Fig. 1 Fig. 1 Fig. 1 Structure of the belt cover layer Entire region Entire region Entire region Sealant layer thickness (mm) 2,0 3,5 5,0 Type of sealant Dien rubber Dien rubber Dien rubber Distance L (mm) 11 11 11 resistance 107 107 107 Tire puncture sealing properties 107 108 109 Driving comfort 100 100 99 [Table 1-III] Example 6 Example 7 Example 8 Structure of the carcass layer Fig. 1 Fig. 1 Fig. 1 Structure of the belt cover layer Entire region Entire region Entire region Sealant layer thickness (mm) 6,0 2,0 2,0 Type of sealant Dien rubber Silicone-based composition Silicone-based composition Distance L (mm) 11 11 9 resistance 107 109 109 Tire puncture sealing properties 110 107 110 Driving comfort 97 100 100

[0042] As can be seen from Table 1, the durability and puncture sealing properties of the pneumatic tires in Examples 1 to 8 were improved compared to the prior art example. In the pneumatic tire of Example 6, the thickness of the sealant layer was set relatively thick, which worsened the ride comfort. List of reference symbols 1 tread section 2 Side wall section 3 bead section 4 Carcass layer 4A Body section 4B Folded Section 4e End 5 bead core 6 bead fillers 7th belt layer 73e End section 8 Belt cover layer 10 Tire inner surface 20 Sealant layer 20e Final Section QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2003-080909 A

[0004] JP 2018-503725 B

[0030] JP 2022-550962 B

[0030]

Claims

[1] Pneumatic tires, including: a tread section that extends in a circumferential direction of the tire and has a ring shape; a pair of sidewall sections arranged on both sides of the tread section; and a pair of bead sections, each arranged in the tire radial direction on the inner sides of the sidewall sections; at least one carcass layer mounted between the pair of bead sections; and a belt layer arranged on an outer circumferential side of the carcass layer in the tread section, wherein the carcass layer is folded around a bead core of each of the bead sections from an inside to an outside of the tire; wherein one end of a folded-over section of the carcass layer is arranged on an inner side in the tire width direction relative to an end section of the belt layer, a sealant layer is formed on the inner surface of a tire in the tread section, and an end section of the sealant layer is located in a shoulder section in the direction of the tire width and is arranged on an outside in the direction of the tire width relative to the end of the folded-over section of the carcass layer. [2] Pneumatic tires according to claim 1, comprising a belt cover layer arranged on an outer circumferential side of the belt layer, wherein The belt cover layer is arranged to cover at least the end section of the belt layer in the tire width direction. [3] Pneumatic tires according to claim 1 or 2, wherein the sealant layer has a thickness in the range of 2.0 mm to 5.0 mm. [4] Pneumatic tires according to any one of claims 1 to 3, wherein the sealant forming the sealant layer has a glass transition temperature in the range of -120 °C to -40 °C. [5] Pneumatic tire according to any one of claims 1 to 4, wherein the sealant forming the sealant layer is composed of a silicone-based composition. [6] Pneumatic tires according to claim 5, wherein the silicone-based composition is a two-part curable silicone. [7] Pneumatic tire according to any one of claims 1 to 6, wherein at all points of the belt layer which is positioned on an innermost side in the tire radial direction, the distance L from the belt layer to the sealant layer is 10 mm or less. [8] Pneumatic tire according to any one of claims 1 to 7, wherein a sound-absorbing element is arranged along the circumferential direction of the tire on an inner side of the sealant layer in the radial direction of the tire. [9] Method for manufacturing the pneumatic tire according to any one of claims 1 to 7, wherein the method comprises: Manufacturing a pneumatic tire excluding the sealant layer; and afterward When forming the sealant layer by applying sealant to the inner tire surface in the tread section, set the temperature of the sealant to be applied to the inner tire surface to 70 °C or fewer. [10] Method for manufacturing the pneumatic tire according to claim 9, comprising: arranging a sound-absorbing element along the tire circumferential direction on an inner side of the sealant layer in the tire radial direction.

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