tire

Abstract

The tire (1) includes: a sidewall reinforcing rubber (2) having a crescent-shaped cross section and disposed in the sidewall portion (1b) of the tire; a low thermal conductivity member (3) having a lower thermal conductivity than the sidewall reinforcing rubber; and a communication device (10) wherein the low thermal conductivity member is positioned between the sidewall reinforcing rubber and the communication device.

Description

Technical Field

[0001] This disclosure relates to tires.

[0002] This application claims priority to Japanese Patent Application No. 2021-199587, filed in Japan on December 8, 2021, the entire contents of which are incorporated herein by reference. Background Technology

[0003] Tires with sidewall reinforcement rubber already exist (Patent Document 1).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2013-71468 Summary of the Invention

[0007] The problem the invention aims to solve

[0008] The inventors of this application have achieved the placement of communication devices (e.g., RF tags) within the aforementioned conventional tires. Furthermore, the inventors of this application have achieved a novel construction that can suppress damage to the communication devices caused by heat generated by the sidewall reinforcement during run-flat driving.

[0009] Providing tires that can suppress the heat generated by the sidewall reinforcing rubber during run-flat driving can be helpful in preventing damage to communication devices.

[0010] Solution for solving the problem

[0011] The tire of this application is a tire that includes:

[0012] Sidewall reinforcement rubber with a crescent-shaped cross-section is arranged in the sidewall portion of the tire;

[0013] Low thermal conductivity components, which have a lower thermal conductivity than the sidewall reinforcing rubber; and

[0014] Communication devices, in which

[0015] The low thermal conductivity component is positioned between the tire sidewall reinforcing rubber and the communication device.

[0016] The effects of the invention

[0017] This application provides a tire that can suppress damage to communication devices caused by heat generated by the sidewall reinforcement during run-flat driving. Attached Figure Description

[0018] [ Figure 1 ] Figure 1It is a cross-sectional view in the tire width direction showing a portion of a tire according to one of the disclosed embodiments.

[0019] [ Figure 2 ] Figure 2 This is a perspective view showing an example of a communication device that can be used in a tire according to any of the disclosed embodiments.

[0020] [ Figure 3 ] Figure 3 It shows the disassembled Figure 2 An exploded perspective view of the communication device in the image. Detailed Implementation

[0021] The tires described in this application are suitable for use in any type of pneumatic tire, particularly pneumatic tires for passenger cars.

[0022] The following description, with reference to the accompanying drawings, illustrates an embodiment of the tire of this application through examples.

[0023] Common components and parts appearing in the accompanying drawings have the same reference numerals. In some drawings, the tire width direction is indicated by the reference numeral "WD", the tire radial direction by the reference numeral "RD", and the tire circumferential direction by the reference numeral "CD". In this specification, the side closer to the tire cavity is referred to as the "tire inner side", while the side farther from the tire cavity is referred to as the "tire outer side".

[0024] Figure 1 A tire 1 according to one of the disclosed embodiments is shown. Figure 1 This is a cross-sectional view showing a portion of a tire (specifically, the portion of the tire on the side opposite to the tire's equatorial plane CL) according to one of the disclosed embodiments, in the tire width direction. Figure 1 The tire 1 in the embodiment is a pneumatic tire for passenger cars.

[0025] The tire 1 according to any of the disclosed embodiments can be any type of tire.

[0026] The tire 1 includes a tire body 1M and a communication device 10. The tire body 1M corresponds to the part of the tire 1 other than the communication device 10.

[0027] In the following text, unless otherwise specified, the positional relationships, dimensions, etc. of each element shall be determined under the reference condition that the tire 1 is mounted on a suitable rim, set with a specified internal pressure, and is unloaded. The width of the contact patch in the tire width direction that contacts the road surface when the tire 1 is mounted on a suitable rim, set with a specified internal pressure, and subjected to maximum load is called the tire contact width, and the end of the contact patch in the tire width direction is called the contact end.

[0028] In this specification, the term "applicable rim" refers to a standard rim of an applicable size specified or to be specified in an industry standard valid in the region where pneumatic tires are manufactured and used (measurement rims in the ETRO standards manual and design rims in the TRA yearbook). Such industry standards include, for example, the JATMA (Japan Automobile Tire Manufacturers Association) yearbook, the ETRO (European Tire & Rim Technology Organization) standards manual, or the TRA (Tire & Rim Association) yearbook in the United States. However, for sizes not specified in the aforementioned industry standards, the term "applicable rim" refers to a rim having a width corresponding to the bead width of the pneumatic tire. In addition to currently specified sizes, "applicable rim" also includes sizes to be specified in the aforementioned industry standards. Examples of "sizes to be specified" may include sizes designated as "FUTURE DEVELOPMENTS" in the 2013 edition of ETRO.

[0029] In this specification, the term "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity of a single wheel for the applicable size and ply rating, as specified or to be specified in industry standards such as the aforementioned JATMA Yearbook. However, for sizes not specified in the aforementioned industry standards, the term "specified internal pressure" refers to the air pressure (maximum air pressure) corresponding to the maximum load capacity defined for each vehicle with the tire mounted. In this specification, the term "maximum load" refers to the load corresponding to the maximum load capacity of a tire of the applicable size defined in the aforementioned industry standards, or, for sizes not defined in the aforementioned industry standards, the load corresponding to the maximum load capacity defined for each vehicle with the tire mounted.

[0030] First, the tire body 1M will be described.

[0031] like Figure 1 As shown, the tire body 1M includes a tread portion 1a, a pair of sidewall portions 1b extending radially inward from both ends of the tread portion 1a in the tire width direction, and a pair of bead portions 1c disposed at the radially inward end of each sidewall portion 1b. The tread portion 1a is the tire width direction portion of the tire body 1M between a pair of contact ends. The bead portions 1c are configured to contact the rim radially inward and outerly in the tire width direction when the tire 1 is mounted on a rim.

[0032] The tire body 1M includes a pair of sidewall portions 1d extending radially inward from both ends of the tread portion 1a in the tire width direction. The sidewall portions 1d are composed of a sidewall portion 1b and a bead portion 1c.

[0033] The tire body 1M includes a pair of bead cores 4a, a pair of bead fillers 4b, a tire body 5, a belt 6, tread rubber 7, sidewall rubber 8, an inner liner 9, and a pair of sidewall reinforcing rubbers 2.

[0034] The bead core 4a is embedded in the corresponding bead portion 1c. The bead core 4a includes a plurality of bead lines covered with rubber. The bead lines are preferably made of metal (e.g., steel). The bead lines can be made of, for example, monofilaments or twisted yarns. The bead lines can be made of organic fibers or carbon fibers.

[0035] The bead filler 4b is positioned radially outward of the tire relative to the corresponding bead core 4a. The bead filler 4b extends radially outward in a tapered manner. The bead filler 4b is made of, for example, rubber.

[0036] The tire carcass 5 extends between a pair of bead cores 4a and forms a ring. The tire carcass 5 consists of one or more (in) Figure 1 In the embodiment described, the tire carcass ply 5a consists of two layers. Each tire carcass ply 5a includes one or more tire carcass cords 5c and a covering rubber 5r covering the tire carcass cords 5c. Figure 1 The tire cord 5c can be formed from monofilaments or twisted yarns.

[0037] The carcass cord 5c is preferably made of organic fibers (such as polyester, nylon, rayon and aramid).

[0038] The carcass ply 5a includes a ply body 5M located between a pair of bead cores 4a. The carcass ply 5a may also include ply fold-back portions 5T that extend from both ends of the ply body 5M and fold back around the bead cores 4a from the inside in the tire width direction toward the outside in the tire width direction. Alternatively, the carcass ply 5a may not include the ply fold-back portions 5T.

[0039] The main body of the ply 5M is positioned inside the tire width direction relative to the bead filler 4b and the bead core 4a. The ply fold-back portion 5T is positioned outside the tire width direction relative to the bead filler 4b and the bead core 4a.

[0040] The carcass 5 is preferably a radial structure, but can also be a bias structure.

[0041] The belt 6 is arranged radially outward of the tire relative to the crown portion of the tire carcass 5. The belt 6 includes one or more belt layers 6a. Each belt layer 6a includes one or more belt cords and a cover rubber covering the belt cords. The belt cords can be formed from monofilaments or twisted yarns. The belt cords can be made of metal (e.g., steel) or organic fibers (such as polyester, nylon, rayon, and aramid).

[0042] At the tread portion 1a, the tread rubber 7 is positioned radially outward of the tire via the belt 6. The tread rubber 7 constitutes the tread surface, which is the radially outward surface of the tire at the tread portion 1a. Tread patterns are formed on the tread surface.

[0043] The sidewall rubber 8 is positioned on the sidewall portion 1b. The sidewall rubber 8 forms the outer surface of the sidewall portion 1b in the tire width direction. The sidewall rubber 8 is positioned relative to the tire carcass 5 in the tire width direction. The sidewall rubber 8 is positioned relative to the bead filler 4b in the tire width direction. The sidewall rubber 8 is formed integrally with the tread rubber 7.

[0044] The inner liner 9 is disposed inside the tire carcass and can be laminated, for example, inside the tire carcass 5. The inner liner 9 is made, for example, of a butyl rubber with low permeability. Examples of butyl rubbers include butyl rubber and halogenated butyl rubbers, which are derivatives of butyl rubber. The inner liner 9 is not limited to butyl rubber and can be made of other rubber components, resins, or elastomers.

[0045] Sidewall reinforcing rubber 2 is arranged in the sidewall portion 1b. The sidewall reinforcing rubber 2 is embedded in the corresponding sidewall portion 1b. Each sidewall reinforcing rubber 2 is arranged on the inner side of the tire body 5 in the tire width direction. Each sidewall reinforcing rubber 2 is arranged on the outer side of the inner liner 9 in the tire width direction. The sidewall reinforcing rubber 2 has a crescent-shaped cross-section, and in the cross-section in the tire width direction, the thickness of the crescent-shaped cross-section gradually decreases in the tire radial direction towards both the inner and outer sides. In addition, the crescent-shaped cross-section is curved in a convex manner towards the outer side in the tire width direction. In this way, the tire 1 is constructed as a run-flat tire.

[0046] The sidewall reinforcement rubber 2 is configured to reinforce the sidewall portion 1d, and in the case of low internal pressure of the tire 1 due to punctures or other reasons, it helps to support the weight of the vehicle body and suppress the vertical deflection of the tire 1, thus allowing the vehicle to travel a certain distance.

[0047] The communication device 10 will be described below.

[0048] The communication device 10 can be of any configuration, as long as the configuration enables wireless communication between the communication device 10 and a predetermined external device (e.g., a reader or reader / writer) located outside the tire 1. Therefore, there are no particular limitations on the configuration of the communication device 10.

[0049] The communication device 10 preferably includes an RF tag. The RF tag is also known as an "RFID tag". The RF tag is preferably passive, but it can also be active.

[0050] Alternatively or attached to an RF tag, the communication device 10 may include an accelerometer for detecting the acceleration of the tire 1 and an internal pressure sensor for detecting the internal pressure of the tire 1.

[0051] Figure 2 and Figure 3 An example of a communication device 10 is shown. In this example, the communication device 10 includes an RF tag. In this example, the communication device 10 includes an RF tag 10e and a cover portion 10f. The RF tag 10e includes an IC chip 10c and an antenna portion 10b. The RF tag 10e is of a passive type.

[0052] The IC chip 10c operates, for example, by an induced electromotive force generated by radio waves received by the antenna section 10b. The IC chip 10c includes, for example, a controller and a memory unit.

[0053] The memory unit can store any information. For example, the memory unit can store the identification information of tire 1. The identification information of tire 1 is, for example, unique identification information that can distinguish each tire from multiple tires, such as the manufacturer of tire 1, the manufacturing plant of tire 1, and the manufacturing date of tire 1. The memory unit can store tire history information, such as the tire's driving distance, the number of sudden braking events, the number of sudden starts, and the number of sudden turns. Sensors that detect, for example, tire internal temperature, tire internal pressure, and tire acceleration can also be placed in the tire cavity, and the memory unit stores the information detected by the sensors. In this case, the RF tag 10e can wirelessly communicate with the sensors via the antenna section 10b to obtain the information detected by the sensors.

[0054] The controller is configured to read information from memory cells.

[0055] The antenna section 10b includes a pair of antennas 10b1 and 10b2. These antennas 10b1 and 10b2 are respectively connected to opposite ends of the IC chip 10c. The antenna section 10b is configured to allow transmission of information to and reception of information from the aforementioned predetermined external device located outside the tire 1. Figure 2 and Figure 3 In the example, antennas 10b1 and 10b2 both extend in a straight line, but antennas 10b1 and 10b2 can both extend to have any shape, such as a waveform.

[0056] The entire RF tag 10e is covered by a cover portion 10f. The cover portion 10f is formed of, for example, rubber or resin.

[0057] In this example, the cover 10f includes a pair of sheet-like cover members 10f1 and 10f2. The pair of cover members 10f1 and 10f2 are stacked to sandwich the RF tag 10e between the pair of cover members 10f1 and 10f2. The pair of cover members 10f1 and 10f2 are preferably secured to each other, for example, by adhesion.

[0058] In this respect, the covering part 10f can be composed of a single component.

[0059] In this example, the cover portion 10f is quadrilateral in the plan view. However, the cover portion 10f can be any shape in the plan view.

[0060] The communication device 10 may not include the coverage section 10f, that is, it may consist only of the RF tag 10e.

[0061] By using the antenna section 10b, the communication device 10 constructed as described above can receive information transmitted via radio waves or magnetic fields from the aforementioned predetermined external device. Rectification (in the case of radio waves) or resonance (in the case of magnetic fields) generates power in the antenna section 10b of the communication device 10, and the memory cell of the IC chip 10c and the controller perform predetermined operations. For example, the controller reads information from the memory cell and returns (transmits) the information via radio waves or magnetic fields from the antenna section 10b to the aforementioned predetermined external device. The aforementioned predetermined external device receives the radio waves or magnetic fields from the communication device 10. The aforementioned predetermined external device can obtain the received information to access the information stored in the memory cell of the IC chip 10c within the communication device 10.

[0062] Based on the above, the communication device 10 can have any configuration other than that shown in this example.

[0063] The communication device 10 may be provided with a longitudinal direction LD, a short side direction SD, and a thickness direction TD. The longitudinal direction LD, the short side direction SD, and the thickness direction TD are perpendicular to each other.

[0064] like Figure 2 and Figure 3 As shown, when the communication device 10 includes an RF tag 10e, the longitudinal direction LD of the communication device 10 is parallel to the extending direction of the antenna portion 10b. When the antennas 10b1 and 10b2 of the antenna portion 10b have a wave shape, the extending direction of the antenna portion 10b refers to the extending direction of the amplitude center line of each of the antennas 10b1 and 10b2. In the communication device 10, when the communication device 10 includes a cover portion 10f, the thickness direction TD of the communication device 10 refers to the thickness direction of the cover portion 10f, and when the communication device 10 does not include the cover portion 10f, it refers to the thickness direction of the IC chip 10c.

[0065] The length of the RF tag 10e in the longitudinal LD ​​is preferably, for example, 20 mm or more or 50 mm or more. The length of the RF tag 10e in the longitudinal LD ​​is preferably, for example, 100 mm or less or 70 mm or less.

[0066] The length of the RF tag 10e in the short side direction SD is preferably, for example, less than 10 mm or less than 8 mm.

[0067] The length of the RF tag 10e in the thickness direction TD is preferably, for example, less than 5 mm or less than 2 mm.

[0068] When the communication device 10 includes a cover portion 10f, the length of the communication device 10 in the longitudinal direction LD is preferably, for example, 30 mm or more or 60 mm or more. The length of the RF tag 10e in the longitudinal direction LD is preferably, for example, 110 mm or less or 80 mm or less.

[0069] When the communication device 10 includes a cover portion 10f, the length of the communication device 10 in the short side direction SD is preferably, for example, 20 mm or less or 15 mm or less.

[0070] When the communication device 10 includes a cover portion 10f, the length of the communication device 10 in the thickness direction TD is preferably, for example, 6 mm or less or 3 mm or less.

[0071] The thickness of each of the covering members 10f1 and 10f2 of the covering portion 10f is preferably, for example, 0.5 mm or more. The thickness of each of the covering members 10f1 and 10f2 of the covering portion 10f is preferably, for example, 1 mm or less.

[0072] exist Figure 1 In one embodiment, the communication device 10 is embedded in the tire body 1M. The communication device 10 can be placed at any location on the tire body 1M.

[0073] During the production of tire 1, the green tire constituting the tire body 1M and the communication device 10 are housed in a mold for forming the tire and undergo vulcanization molding.

[0074] In this respect, the communication device 10 can be attached to the outer or inner surface of the tire body 1M, rather than being embedded in the tire body 1M.

[0075] like Figure 1 As shown, the tire 1 (specifically the tire body 1M) includes one or more low thermal conductivity members 3 with a thermal conductivity lower than that of the sidewall reinforcing rubber 2. The one or more low thermal conductivity members 3 are positioned between the sidewall reinforcing rubber 2 and the communication device 10.

[0076] exist Figure 1In this embodiment, the carcass cords 5c (cords) of the carcass 5 constitute the corresponding low thermal conductivity members 3. In other words, each low thermal conductivity member 3 is constituted by the carcass cords 5c (cords) of the carcass 5. In order for the carcass cords 5c to constitute low thermal conductivity members 3 (and thus have a lower thermal conductivity than the sidewall reinforcing rubber 2), for example, the carcass cords 5c can be made of organic fibers such as polyester, nylon, rayon, and aramid.

[0077] When the low thermal conductivity component 3 is composed of cords, the thermal conductivity of the low thermal conductivity component 3 shall be measured according to JIS R 1611:2010. When the low thermal conductivity component 3 is composed of components other than cords (such as rubber components), the thermal conductivity of the low thermal conductivity component 3 shall be measured according to JIS A 1412-2:1999. The thermal conductivity of rubber components (sidewall reinforcing rubber 2, carcass cover rubber 5r, tread rubber 7, sidewall rubber 8, and the cover 10f of the communication device 10, etc.) shall be measured according to JIS A 1412-2:1999.

[0078] During driving when the tire 1 has low internal pressure due to punctures or other reasons (during run-flat driving), heat is easily generated from the sidewall reinforcement rubber 2. However, in this embodiment, a low thermal conductivity member 3 is positioned between the sidewall reinforcement rubber 2 and the communication device 10. Therefore, the low thermal conductivity member 3 positioned between the sidewall reinforcement rubber 2 and the communication device 10 can shield the heat from the sidewall reinforcement rubber 2, thereby suppressing heat transfer to the communication device 10. This can prevent heat damage to the communication device 10.

[0079] By suppressing damage to the communication device 10, even if the tire body 1M suffers a malfunction due to a puncture or the like, the loss of the communication function of the communication device 10 can be suppressed. From the viewpoint of managing the tire 1, it is expected that the communication device 10 will still have communication function even after the tire 1 has been removed from the vehicle for disposal due to a malfunction or the like.

[0080] The fact that the carcass cords 5c (cords) attached to or alternatively attached to the carcass 5 constitute the corresponding low thermal conductivity member 3 means that cords other than the carcass cords 5c can constitute the low thermal conductivity member 3, and any member other than the cords can also constitute the low thermal conductivity member 3. For example, the covering rubber 5r of the carcass 5 can constitute the low thermal conductivity member 3.

[0081] When the low thermal conductivity component 3 is composed of components other than rubber components (such as cords of the tire carcass cord 5c), the thermal conductivity of the low thermal conductivity component 3 is preferably lower than the thermal conductivity of each of the rubber components constituting the tire 1 (such as the tread rubber 7, the sidewall rubber 8, and the cover 10f of the communication device 10).

[0082] When the low thermal conductivity component 3 is made of a rubber component (e.g., the cover rubber 5r of the tire body 5), the thermal conductivity of the low thermal conductivity component 3 is preferably lower than that of all other rubber components constituting the tire 1 (such as the tread rubber 7, the sidewall rubber 8, and the cover 10f of the communication device 10).

[0083] When the low thermal conductivity member 3 is composed of cords (e.g., carcass cords 5c), the cord endcount is preferably 20 cords / 50 mm or more. Thus, the low thermal conductivity member 3 can effectively shield heat from the sidewall reinforcing rubber 2, further suppressing heat damage to the communication device 10.

[0084] The preferred arrangement density of the above-mentioned cords is 65 cords per 50 mm or less.

[0085] like Figure 1 As shown in the embodiment, one or more low thermal conductivity components 3 are preferably positioned in the tire width direction between the sidewall reinforcing rubber 2 and the communication device 10. Figure 1 As shown in the embodiment, the communication device 10 can be positioned on the outer side of the tire width direction relative to the sidewall reinforcement rubber 2, or it can be positioned on the inner side of the tire width direction relative to the sidewall reinforcement rubber 2.

[0086] like Figure 1 As shown in the embodiment, the communication device 10 is preferably positioned between the tire sidewall rubber 8 and the low thermal conductivity member 3. Specifically, as Figure 1 As shown in the embodiment, the communication device 10 is preferably positioned in the tire width direction between the sidewall rubber 8 and one or more low thermal conductivity members 3. The one or more low thermal conductivity members 3 are positioned inside the tire width direction relative to the sidewall rubber 8.

[0087] The sidewall rubber 8 is located on the outermost radial side of the tire, thus providing high heat dissipation performance. Therefore, since the communication device 10 is positioned between the sidewall rubber 8 and the low thermal conductivity member 3, the heat applied to the communication device 10 through the heat dissipation function of the sidewall rubber 8 can be further reduced, and thus heat damage to the communication device 10 can be further suppressed.

[0088] In this case, such as Figure 1 As shown, the communication device 10 is preferably in contact with the tire sidewall rubber 8.

[0089] like Figure 1 As shown, the communication device 10 is preferably embedded in the sidewall portion 1d of the tire 1.

[0090] Typically, metal weakens radio waves between the communication device 10 and the predetermined external device (e.g., a reader or reader / writer), thereby reducing communication performance between the communication device 10 and the predetermined external device, and thus shortening the communication distance between the communication device 10 and the predetermined external device. In the tire body 1M, metal (e.g., steel) can be used in the belt 6, bead core 4a, etc. Furthermore, the sidewall portion 1d typically has less metal than the tread portion 1a. Therefore, by arranging the communication device 10 in the sidewall portion 1d, compared to arranging the communication device 10 in the tread portion 1a, communication performance can be improved, and the communication distance between the communication device 10 and the predetermined external device can be extended.

[0091] The communication device 10 is preferably embedded in the sidewall portion 1d of the tire body 1M, which is located on the outer side of the tire body 5 in the tire width direction.

[0092] The communication device 10 is preferably oriented such that the thickness direction TD of the communication device 10 is substantially along the tire width direction. Figure 1 ).

[0093] The orientation of the communication device 10 is arbitrary. However, from the viewpoint of, for example, the durability of the communication device 10, the communication device 10 is preferably oriented such that the longitudinal direction LD of the communication device 10 is substantially along the circumferential direction of the tire, as... Figure 1 As shown in the embodiment. In this respect, the communication device 10 can be oriented such that the short side direction SD of the communication device 10 is substantially along the tire circumference.

[0094] like Figure 1 As shown in the embodiment, the communication device 10 is preferably arranged in the sidewall portion 1b. The sidewall portion 1b generally tends to have less metal than the bead portion 1c. Therefore, by arranging the communication device 10 in the sidewall portion 1b, compared with arranging the communication device 10 in the bead portion 1c, communication performance can be improved, and the communication distance between the communication device 10 and the aforementioned predetermined external device can be extended.

[0095] like Figure 1 As shown, the outer radial end 10u of the tire of the communication device 10 (more preferably the entire communication device 10) is preferably located radially outside the tire relative to the outer radial end of the tire bead core 4a. More preferably, the outer radial end 10u of the tire is located radially outside the tire relative to the radial center of the tire bead filler 4b. For example, the outer radial end 10u of the tire is preferably located radially outside the tire relative to the outer radial end 4bu of the tire bead filler 4b.

[0096] The above configuration is particularly preferred when tire 1 is a pneumatic tire for passenger cars.

[0097] When the communication device 10 is arranged in the side wall portion 1b as described above, such as Figure 1 As shown in the example, the outer radial end 10u of the communication device 10 is preferably positioned radially inside the tire relative to the outer radial end 5e of the ply fold-back portion 5T of the tire carcass 5. Therefore, communication performance can be improved, and the communication distance between the communication device 10 and the aforementioned predetermined external device can be extended. Furthermore, the communication device 10 can be arranged in, for example, a portion of the tire body 1M where strain is relatively small during tire 1 rolling. Therefore, the durability of the communication device 10 and thus the tire 1 can be improved.

[0098] The radial distance between the outermost radial end 10u of the tire of the communication device 10 and the outermost radial end 5e of the tire of the ply fold-back portion 5T of the tire carcass 5 is preferably 3mm to 30mm, more preferably 5mm to 15mm.

[0099] The above configuration is particularly preferred when tire 1 is a pneumatic tire for passenger cars.

[0100] like Figure 1 As shown in the example, the outermost radial end 5e of the ply fold-back portion 5T of the carcass 5 is preferably positioned radially outward relative to the outermost radial end 4bu of the bead filler 4b. In this respect, the outermost radial end 5e of the ply fold-back portion 5T of the carcass 5 can be positioned at the same radial position as the outermost radial end of the bead filler 4b, or it can be positioned radially inward relative to the radial position of the outermost radial end of the bead filler 4b.

[0101] The outermost radial end 5e of the ply fold-back portion 5T of the tire carcass 5 can be positioned radially outward relative to the maximum tire width position of the tire body 1M, and can also be positioned radially inward relative to the maximum tire width position of the tire body 1M. The term "maximum tire width position of the tire body 1M" refers to the radial position where the tire body 1M's dimension in the tire width direction becomes largest.

[0102] like Figure 1 As shown in the example, the communication device 10 preferably contacts the outer surface of the tire carcass 5 in the tire width direction, and more preferably contacts the outer surface of the ply fold-back portion 5T of the tire carcass 5 in the tire width direction.

[0103] The above configuration is particularly preferred when tire 1 is a pneumatic tire for passenger cars.

[0104] The tire rubber composition described in detail below is preferably used in at least a portion of the rubber constituting tire 1 (e.g., at least one of the sidewall rubber 8, tread rubber 7, cover rubber 5r of the carcass ply 5a, separator between the carcass ply 5a, cover rubber of the belt ply 6a, and bead filler 4b). By using the tire rubber composition, tire 1 can be achieved that has low rolling resistance and high durability, and that suppresses the increase in resistance without compromising reinforcement and durability.

[0105] In particular, when tire rubber components are used in the sidewall rubber 8, reduced wear can be achieved, and thus rolling resistance can be reduced. Furthermore, heat generated from the sidewall rubber 8 due to deformation during rolling is reduced. Therefore, heat damage to the communication device 10 can be further suppressed accordingly.

[0106] <Tire Rubber Composition>

[0107] The above-mentioned tire rubber composition is formulated by blending 35 to 50 parts by weight of a rubber component (including 20 to 40 parts by weight of styrene-butadiene rubber and 60 to 80 parts by weight of natural rubber) based on 100 parts by weight of rubber components, resulting in a composition of 30m. 2 / g to 43m 2 It is obtained by using carbon black with a nitrogen adsorption specific surface area (N2SA) of / g and 5 parts by mass or less of oil.

[0108] Examples of rubber components used in the above-mentioned tire rubber composition include at least styrene-butadiene rubber (SBR) and natural rubber (NR).

[0109] In 100 parts by weight of the rubber component, the content of styrene-butadiene rubber (SBR) is preferably 20 to 40 parts by weight. Setting the SBR content to 20 parts by weight or more improves resistance to crack propagation under low strain, thereby enhancing the processability of the uncured rubber. Setting the SBR content to 40 parts by weight or less achieves further loss reduction.

[0110] Examples of styrene-butadiene rubber that can be used include solution-polymerized styrene-butadiene rubber, emulsion-polymerized styrene-butadiene rubber, and modified styrene-butadiene rubber.

[0111] In 100 parts by weight of rubber component, the content of natural rubber is preferably 60 to 80 parts by weight. Setting the content of natural rubber to 60 parts by weight or more can improve the resistance to crack propagation under high strain. Setting the content of natural rubber to 80 parts by weight or less can improve the processability of uncured rubber and reduce costs.

[0112] Examples of natural rubber include natural rubber used in the tire industry, such as RSS#3, TSR20, and SIR20.

[0113] In addition to the aforementioned natural rubber (NR) and styrene-butadiene rubber (SBR), at least one of the following may be used if required: butadiene rubber (BR), isoprene rubber (IR), butyl rubber (IIR), halogenated butyl rubber, chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and ethylene propylene diene monomer (EPDM).

[0114] The carbon black used in the aforementioned tire rubber composition was a carbon black with a nitrogen adsorption specific surface area (N2SA, measured according to JISK 6217-2:2001) of 30 m². 2 / g to 43m 2 / g of carbon black. The reason why the nitrogen adsorption specific surface area (N2SA) of the carbon black is limited to the above range is that the dispersibility of the carbon black is improved by using carbon black with a large particle size. Preferably, the nitrogen adsorption specific surface area (N2SA) is 33m². 2 / g to 40m 2 / g.

[0115] Carbon blacks with these properties can be FEF, GPF, SRF, etc.

[0116] Based on 100 parts by weight of the rubber component, the content of the aforementioned carbon black is preferably 35 parts by weight or more. Therefore, the mechanical strength of the rubber can be ensured.

[0117] Based on 100 parts by weight of the rubber component, the content of the aforementioned carbon black is preferably 50 parts by weight or less. This allows for reduced losses and also reduces the heat generated from the aforementioned tire rubber composition due to deformation during rolling. Consequently, heat damage to the communication device 10 can be further suppressed accordingly.

[0118] Examples of oils used in the above-mentioned tire rubber composition include at least one oil selected from paraffinic oils, cycloalkanes, aromatic oils, and aromatic compound oils, and these oils may be commercially available products.

[0119] For example, as a paraffinic oil, commercially available products can be used, such as the paraffinic oil marketed as "Super Oil Y22" manufactured by JX Nippon Oil & Energy Corporation. Naphthenic oils can be hydrogenated or non-hydrogenated. As a cycloalkane oil, commercially available products can be used, such as the "A / OMIX" cycloalkane oil containing straight-run pitch manufactured by SANKYO YUKAKOGYO KK.

[0120] Based on 100 parts by weight of the rubber component, the content of the above oil is 5 parts by weight or less (including 0 parts by weight).

[0121] By setting the content of the aforementioned oil to 5 parts by mass or less, the mechanical strength of the rubber can be improved. Even without the aforementioned oil (0 parts by mass), compounding agents such as carbon black can be sufficiently dispersed to obtain the necessary rubber properties. In particular, the oil content is preferably 0 to 3 parts by mass.

[0122] For the purpose of providing additional conductivity to further reduce resistance and for the purpose of further improving durability, the tire rubber composition preferably also includes at least one of Ketjen black and carbon nanotubes (CNTs).

[0123] As usable carbon nanotubes (CNTs), examples include rod-shaped or wire-shaped graphene sheets, vapor-grown carbon fibers (VGCF), etc., and commercially available products such as C100 (manufactured by Arkemasya) or NC7000 (manufactured by Nanocyl) can be used. These carbon nanotubes (CNTs) provide additional electrical conductivity and, unlike the aforementioned carbon black, interact less with rubber, resulting in a lower elastic modulus and increased elongation at break (Eb) in the high-strain region of the stress-strain curve. Accordingly, when the Eb of the rubber is high during crack propagation, crack tip energy is mitigated, thereby improving resistance to crack propagation.

[0124] As Kojic black, various grades of Kojic black containing hollow shell-like particles and having high electrical conductivity can be used. Examples of Kojic black that can be used include Kojic black EC300J [granular], Kojic black EC600JD [granular] manufactured by Lion Corporation, CARBON ECP [powdered Kojic black EC300J], CARBON ECP600JD [powdered Kojic black EC600JD], and at least one of molybdenite, tungstenite, and lead ore.

[0125] Based on 100 parts by weight of rubber component, the total blending amount of Ketjen Black and carbon nanotubes is preferably 0.1 parts by weight to 6 parts by weight, more preferably 1.0 parts by weight to 5 parts by weight.

[0126] By setting the total blending amount of Ketjen black and carbon nanotubes to 0.1 parts by mass or more, the rubber compound can be made conductive. By setting such a total blending amount to 6 parts by mass or less, the reduction in the low-loss properties of the rubber can be prevented.

[0127] In the above-mentioned tire rubber composition, carbon black, Ketjen black, and carbon nanotubes having nitrogen adsorption specific surface area (N2SA) satisfying the above-mentioned range are used as fillers. However, for the purpose of providing better electrical conductivity and for the purpose of further improving crack propagation resistance to further improve durability, it is preferable that the blending amount of at least one of Ketjen black and carbon nanotubes in the filler is preferably 2% to 15% by weight, more preferably 2.5% to 12.5% ​​by weight.

[0128] In addition to carbon black, Ketjen black, and carbon nanotubes, other fillers such as silica, clay, talc, and calcium carbonate can be used.

[0129] In addition to the components described above, other components may be appropriately selected and incorporated into the tire rubber composition as needed for the intended purpose. Examples of other components include, for instance, sulfur vulcanizing agents, vulcanizing accelerators such as thiazole-based and sulfenamide-based vulcanizing accelerators, vulcanizing aids, zinc oxide (zinc white), stearic acid, anti-aging agents, antioxidants, anti-ozone agents, colorants, lubricants, silane coupling agents, foaming agents, additives such as foaming aids, and various known compounding components commonly used in the tire industry. These other components may be commercially available products.

[0130] The above-mentioned tire rubber composition can be prepared by mixing carbon black, oil and other components having the above-mentioned properties into the rubber composition, and additionally, mixing Ketjen black, carbon nanotubes, zinc white, stearic acid, anti-aging agent, sulfur, vulcanization accelerator and additives appropriately selected according to purpose or need into the rubber composition.

[0131] There are no particular restrictions on the mixing conditions described above. Conditions such as the capacity of the mixing mill, the rotational speed of the rotor, the pressing, the mixing temperature, the mixing time, and the type of mixing mill can be appropriately selected according to the purpose. Examples of such mixing mills include the Banbury mixer, the internal mixer, the mixing mill, and the roller, which are commonly used for mixing rubber compositions.

[0132] When the blending amount of styrene-butadiene rubber in the above tire rubber composition is A parts by mass and the blending amount of natural rubber is B parts by mass, the following rubber composition is regarded as rubber composition X: Based on A parts by mass of styrene-butadiene rubber, the above tire rubber composition containing an amount of A*100 / (A+B) (mass%) has a nitrogen adsorption specific surface area (N2SA) of 30m². 2 / g to 43m 2 / g of carbon black. Additionally, consider the following rubber composition as rubber composition Y: Based on B parts by mass of natural rubber, the above tire rubber composition, containing B*100 / (A+B) (mass%), has a nitrogen adsorption specific surface area (N2SA) of 30m². 2 / g to 43m2 / g of carbon black. Furthermore, the aforementioned tire rubber composition is considered as rubber composition Z. In this case, when the moduli of rubber compositions X, Y, and Z at 50% elongation are considered as Mdx, Mdy, and Mdz (MPa), respectively, preferably, Mdx, Mdy, and Mdz satisfy equation (I):

[0133] 0.9×{Mdx*A / (A +B)+Mdy*B / (A +B)}≥Mdz…(I).

[0134] When the tire rubber composition satisfies formula (I), the increase in resistance is further suppressed without reducing the reinforcing capacity and durability, the rolling resistance is further reduced, and higher durability is achieved.

[0135] As described above, the tire rubber composition is applied to at least one component selected from the following: ply cover rubber of the carcass plies, belt cover rubber of the belt plies, interlayer separator rubber, cushioning rubber, belt undercushion, and bead filler rubber. Preferably, the tire rubber composition is applied to the ply cover rubber because the amount of rubber used for the ply cover rubber is large and has a significant impact on the overall tire wear characteristics; furthermore, the ply cover rubber is positioned at the center of the conductive path from the rim to the tread. Therefore, a pneumatic tire achieving a balance between reduced wear, crack resistance / reinforcement, and conductivity can be realized.

[0136] By using the tire rubber composition constructed as described above, durability in high-strain regions is improved by setting the amount of natural rubber (NR) within a specific range, and low-strain durability is improved without degrading wear reduction by setting the amount of styrene-butadiene rubber (SBR) within a specific range. Furthermore, the reduction in rubber wear is achieved by using carbon black having a nitrogen adsorption specific surface area (N2SA) limited to the aforementioned range, and the reinforcing capacity is improved by setting the amount of oil to a predetermined amount or less. Therefore, the tire rubber composition constructed as described above can help provide tires with low rolling resistance and high durability, while also possessing the same reinforcing capacity and durability as conventional tires, and suppressing the increase in resistance within the tire.

[0137] Furthermore, by comprising 0.1 to 6 parts by mass of at least one of Ketjen black and carbon nanotubes, a tire rubber composition with good conductivity is provided without deteriorating dispersion and low-loss properties. It is known that conductive materials typically exhibit poor dispersibility, deteriorating low-loss properties, and weak interaction with rubber. However, as a result of research into the type and proportion of conductive materials, this application demonstrates that additional conductivity can be provided without deteriorating dispersion and low-loss properties by incorporating at least one of Ketjen black and carbon nanotubes in specific proportions. Additionally, by utilizing the low reinforcing capacity of the aforementioned conductive materials, this tire rubber composition exhibits good durability.

[0138] In addition, the above-mentioned tire rubber composition (blended with at least one of Ketjen black and carbon nanotubes in an amount of 2% to 15% by mass of filler) is advantageous because the tire rubber composition still has the above-mentioned loss reduction and reinforcement capabilities, and also provides additional conductivity and better durability.

[0139] Industrial availability

[0140] The tire described in this application is applicable to any type of pneumatic tire, especially pneumatic tires for passenger cars.

[0141] Explanation of reference numerals in the attached figures

[0142] 1: Tires

[0143] 1M: Tire body

[0144] 1a: Fetal face

[0145] 1b: Side wall portion

[0146] 1c: Bead section

[0147] 1d: Sidewall

[0148] 2: Sidewall reinforcement rubber

[0149] 3: Low thermal conductivity components

[0150] 4a: Bead core

[0151] 4b: Bead filler

[0152] 4bu: The outermost radial end of the tire with rubber filling in the bead.

[0153] 5: Fetus

[0154] 5a: Carcass ply

[0155] 5c: Tire carcass cords (cords)

[0156] 5r: Covered rubber

[0157] 5M: Main body of the fabric layer

[0158] 5T: Cord layer folding section

[0159] 5e: The radial outer end of the tire carcass ply fold-back section.

[0160] 6: Belt

[0161] 6a: Belt layer

[0162] 7: Tread rubber

[0163] 8: Sidewall rubber

[0164] 9: Inner Lining

[0165] 10: Communication device

[0166] 10e: RF tag

[0167] 10b: Antenna section

[0168] 10b1, 10b2: Antenna

[0169] 10f: Covering section

[0170] 10f1, 10f2: Covering components

[0171] 10c: IC chip

[0172] 10u: Radial outer end of the tire of the communication device

[0173] CL: Tire equatorial plane

[0174] WD: Tire width direction

[0175] RD: Tire radial direction

[0176] CD: Tire Circumferential Direction

[0177] LD: Vertical axis of communication device

[0178] SD: Short side direction of the communication device

[0179] TD: Thickness direction of the communication device

Claims

1. A tire, comprising: Sidewall reinforcing rubber, which is arranged in the sidewall portion of the tire and has a crescent-shaped cross-section; A low thermal conductivity component having a lower thermal conductivity than the sidewall reinforcing rubber; and Communication devices, in which The low thermal conductivity component is positioned between the tire sidewall reinforcing rubber and the communication device. The covering rubber of the tire carcass constitutes the low thermal conductivity component, and the thermal conductivity of the covering rubber of the tire carcass constituting the low thermal conductivity component is lower than the thermal conductivity of all other rubber components constituting the tire.

2. The tire according to claim 1, wherein The low thermal conductivity component is made of cord.

3. The tire according to claim 1, wherein The communication device is positioned between the tire sidewall rubber and the low thermal conductivity component.

4. The tire according to claim 2, wherein The communication device is positioned between the tire sidewall rubber and the low thermal conductivity component.

5. The tire according to any one of claims 1 to 4, wherein In 100 parts by weight of the rubber component, the carbon black content in the sidewall rubber of the tire is 50 parts by weight or less.

6. The tire according to any one of claims 1 to 4, wherein The communication device includes an RF tag.

7. The tire according to claim 5, wherein The communication device includes an RF tag.

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