JP2024126537A - tire - Google Patents

Abstract

[Problem] To improve the durability of electronic components attached to a tire during running. [Solution] A tire having a tread portion, a carcass layer, a bead portion composed of a bead apex and a bead core, and a clinch, in which an electronic component is provided between the carcass layer and the clinch, and the loss tangent 70°C tan δCA of the clinch measured in the deformation mode: tension under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, and the longitudinal length L (mm) of the electronic component satisfy the following (Formula 1): 70°C tan δCA×L≦12 (Formula 1) [Selected Figure] FIG. 1

Description

The present invention relates to a tire with embedded electronic components such as RFID.

In recent years, it has been proposed to embed electronic components such as RFID (Radio Frequency Identification) transponders (hereinafter simply referred to as "RFID") in tires in order to record information about the tire at the time of manufacture/shipment and information about the tire while it is being driven, and to communicate with the outside world (for example, Patent Documents 1 to 4).

Special table 2021-506676 publication Special Publication No. 2021-514891 JP 2021-084510 A JP 2021-127114 A

However, if electronic components are embedded inside an unvulcanized tire and then integrated with the tire, shock loads during driving may cause the electronic components to peel off from the rubber material, reducing the durability of the electronic components during driving.

Therefore, the objective of the present invention is to improve the durability of electronic components attached to tires while the vehicle is running.

The present invention relates to
A tire having a tread portion, a carcass layer, a bead portion composed of a bead apex and a bead core, and a clinch,
An electronic component is provided between the carcass layer and the clinch,
The loss tangent 70°C tanδCA of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire is characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 1).
70℃tanδCA×L≦12 (Formula 1)

The present invention makes it possible to improve the durability of electronic components attached to tires while they are in motion.

1 is a schematic cross-sectional view showing a configuration of a tire according to one embodiment of the present invention. FIG. 2 is a schematic plan view showing a configuration of an electronic component. FIG. 11 is a schematic cross-sectional view illustrating the embedding position of an electronic component in a comparative example.

[1] Features of the Tire According to the Present Invention First, the features of the tire according to the present invention will be described.

1. Overview The tire according to the present invention is a tire including a tread portion, a carcass layer, a bead portion including a bead apex and a bead core, and a clinch, and an electronic component is provided between the carcass layer and the clinch. The loss tangent 70°C tan δCA of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, and the longitudinal length L (mm) of the electronic component satisfy the following (Formula 1).
70℃tanδCA×L≦12 (Formula 1)

These features can improve the durability of electronic components attached to the tire while it is in motion, as described below.

2. Mechanism of manifestation of effects in the tire according to the present invention The mechanism of manifestation of the above-mentioned effects in the tire according to the present invention is believed to be as follows.

As described above, in the tire according to the present invention, the electronic components are provided between the carcass layer and the clinch.

The carcass layer is a tire component that forms the tire's framework, and has a much higher elastic modulus than other tire components. Furthermore, since the carcass layer that forms the tire's framework is the center of tire deformation, it is thought that the amount of deformation near the carcass layer during running is smaller than the surrounding area.

On the other hand, since the clinch is the part that is fixed to the rim, it is thought that the amount of deformation during driving is small, just like the carcass layer.

For this reason, if electronic components are provided between the carcass layer and the clinch, the amount of deformation around the electronic components during running can be reduced, preventing the occurrence of peeling of the electronic components within the tire, and it is believed that this can improve the durability of electronic components attached to the tire during running.

However, no matter how small the deformation, the clinch will still deform while the tire is rolling. Depending on the extent of the deformation, it may cause the electronic components to peel off, reducing the durability of the electronic components attached to the tire while it is running.

In order to suppress such clinch deformation and sufficiently prevent the occurrence of delamination of electronic components, it is believed necessary to appropriately control the relationship between the loss tangent of the clinch and the longitudinal length of the electronic component.

That is, the loss tangent tan δ is a viscoelastic parameter that indicates the energy absorption performance, and the larger the value, the more energy is absorbed, the more heat is generated, and the more deformation occurs. If the deformation exceeds the longitudinal length of the electronic component, the electronic component will peel off from the clinch.

Therefore, if the product of the loss tangent of the clinch and the longitudinal length of the electronic component can be controlled to a certain value or less, it is believed that the deformation of the clinch can be appropriately suppressed and the occurrence of detachment of the electronic component can be sufficiently prevented, thereby improving the durability of the electronic component attached to the tire while it is in motion.

Specifically, if the product (70°C tan δCA x L) of the loss tangent of the clinch measured in the deformation mode: tension under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, and the longitudinal length L (mm) of the electronic component is 12 or less, it is possible to appropriately suppress the deformation of the clinch, sufficiently prevent the occurrence of peeling of the electronic component, and improve the durability of the electronic component attached to the tire during driving.

As described above, in the tire according to the present invention, the electronic components are provided between the carcass layer and the clinch, where the amount of deformation around the electronic components during running is thought to be small, and the product of the loss tangent 70°C tan δCA of the clinch and the longitudinal length L (mm) of the electronic components is controlled to a certain value or less to appropriately suppress the deformation of the clinch, thereby sufficiently preventing the occurrence of peeling of the electronic components and improving the durability of the electronic components attached to the tire during running.

In the above, the loss tangent (tan δ) can be measured using a viscoelasticity measuring device such as GABO's "IPLEXER (registered trademark)."

[2] More Preferred Aspects of the Tire According to the Present Invention The tire according to the present invention can achieve even greater effects by adopting the following aspects.

1. Loss Tangent of Tread Portion In the present invention, the loss tangent of the tread portion, 30°C tan δTR, measured under conditions of a temperature of 30°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is preferably 0.25 or less, and more preferably 0.15 or less.

Loss tangent tan δ is a viscoelastic parameter that indicates energy absorption performance; the larger the value, the more energy can be absorbed. Therefore, by setting 30°C tan δTR to a small value in this way, it is possible to maintain sufficient rigidity of the tread portion while driving to absorb energy, reduce the occurrence of deformation in the carcass layer and clinches, and further reduce the amount of deformation around the electronic components, thereby improving the durability of the electronic components attached to the tire while driving.

In this case, it is more preferable that the loss tangent 0°C tan δTR of the tread portion measured in the deformation mode: tension under the conditions of a temperature of 0°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, is 0.50 or more. In this way, by increasing the loss tangent tan δ at low temperatures, it is possible to absorb vibrations at a higher frequency than rolling on the tire surface during running, which is believed to further reduce the amount of deformation around the electronic components and further improve the durability of electronic components attached to the tire during running.

The "tread portion" refers to the area that forms the tire's contact surface, and is the portion radially outward of the carcass, belt layer, belt reinforcing layer, and other components that contain fiber materials. The tread portion may be formed of only one cap rubber layer, or may be formed of two layers with a base rubber layer provided inside the cap rubber layer, or may be formed of three layers, or may be formed of four or more layers. In this case, the thickness of the cap rubber layer in the entire tread portion is preferably 10% or more. It is more preferable that the thickness of the cap rubber layer in the entire tread portion is 70% or more.

The thickness of the cap rubber layer and the thickness of the base rubber layer described above can be calculated by adding up the thickness of the cap rubber layer and the thickness of the base rubber layer in the tread portion measured in a cross section cut out in the radial direction of the tire with the bead portion aligned to the standard rim width.

Here, a "genuine rim" refers to a rim that is determined for each tire by the standard system that includes the standards on which the tire is based. For example, in the case of JATMA (Japan Automobile Tire Manufacturers Association), this refers to the standard rim for the applicable size listed in the "JATMA YEAR BOOK," in the case of ETRTO (The European Tire and Rim Technical Organization), this refers to the "Measuring Rim" listed in the "STANDARDS MANUAL," and in the case of TRA (The Tire and Rim Association, Inc.), this refers to the "Design Rim" listed in the "YEAR BOOK." Reference is made in the order of JATMA, ETRTO, and TRA, and if an applicable size is available at the time of reference, that standard is followed. In the case of tires not specified by the standard, it refers to the rim that can be mounted on a rim and can maintain internal pressure, i.e., the rim that does not leak air between the rim and tire, and has the smallest rim diameter and the next narrowest rim width.

2. Tire weight and maximum load capacity In the present invention, the ratio of the tire weight (kg) to the tire's maximum load capacity (kg) (tire weight/maximum load capacity) is preferably less than 0.0150, and more preferably less than 0.0135. In this way, a tire with a small tire weight compared to the tire's maximum load capacity has a relatively thin rubber, and therefore is thought to be able to sufficiently suppress the temperature rise of the entire tire and reduce the amount of deformation, thereby further improving the durability of electronic components attached to the tire during running.

In the above, "tire weight (kg)" refers to the weight of the tire alone, not including the weight of the rim.

The "maximum load capacity (kg)" can be calculated as WL from the following formula, where Wt (mm) is the tire section width, Ht (mm) is the tire section height, and Dt (mm) is the tire outer diameter measured under normal conditions. Here, the tire section width Wt is the maximum width between the outer surfaces of the sidewalls under normal conditions, excluding any patterns or letters on the side of the tire. The tire section height Ht is half the difference between the tire outer diameter and the nominal rim diameter.
V={(Dt/2) ² - (Dt/2-Ht) ² }×π×Wt
WL=0.000011×V+100

In the above description, "normal condition" refers to a tire mounted on a normal rim, inflated to normal internal pressure, and unloaded. Note that "normal internal pressure" refers to the air pressure specified for each tire by each standard in the standard system including the standard on which the tire is based. For JATMA, it refers to the "maximum air pressure", for ETRTO, it refers to the "inflammation pressure", and for TRA, it refers to the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES". Refer to JATMA, ETRTO, and TRA in that order, and follow the standard if there is an applicable size at the time of reference. In the case of a tire not specified in the standard, it refers to the normal internal pressure (250 KPa or more) of another tire size (specified in the standard) specified with the normal rim as the standard rim. In addition, if multiple normal internal pressures of 250 KPa or more are listed, it refers to the smallest value among them.

3. Relationship between Complex Elastic Modulus of Clinch, Loss Tangent of Bead Apex, and Length of Electronic Component in the Longitudinal Direction In the present invention, the complex elastic modulus of the clinch, specifically, the complex elastic modulus 70°C E*CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain rate of 1%, and a deformation mode: tension, is set to 6 MPa or more, and it is preferable to control the product (70°C tan δBA ^x L) of the loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain rate of 1%, and a deformation mode: tension, of the electronic component in the longitudinal direction L (mm) to 15 or less.

The complex modulus is a parameter that indicates the rigidity of the rubber layer, and it is believed that by increasing the complex modulus 70°C E ^* CA (MPa) of the clinch to 6 MPa or more to increase the rigidity, the deformation of the clinch during running can be reduced.

Because the bead apex is a component that is provided in contact with the clinch, it is believed that, similarly to the clinch, by controlling the product of 70°C tan δBA and the longitudinal length L (mm) of the electronic component to a certain value or less, specifically, 15 or less, it is possible to suppress the concentration of strain on the clinch and more appropriately suppress deformation of the clinch, thereby further improving the durability of the electronic component attached to the tire during driving.

The above-mentioned 70° C. E ^* CA can be measured, like the measurement of the loss tangent, using a viscoelasticity measuring device such as "IPLEXER (registered trademark)" manufactured by GABO.

4. Relationship between the loss tangent of the bead apex, the loss tangent of the clinch, and the longitudinal length of the electronic component In the above, it is preferable to control the loss tangent of the bead apex and the loss tangent of the clinch in relation to the longitudinal length of the electronic component, but considering that the bead apex and the clinch are in contact with each other, it is also preferable to consider the bead apex and the clinch as a set of members and control the relationship between the sum of their loss tangents and the longitudinal length of the electronic component.

Specifically, even if the product ((70°C tan δBA + 70°C tan δCA) x L) of the sum of the loss tangents 70°C tan δBA and 70°C tan δCA of the bead apex and clinch measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain rate of 1%, and a deformation mode of tension, is controlled to be less than 30, it is possible to suppress the concentration of strain on the clinch and more appropriately suppress the deformation of the clinch, and it is believed that the durability of the electronic components attached to the tire during driving can be further improved.

5. Relationship between the complex elastic modulus of the bead apex, the complex elastic modulus of the clinch, and the longitudinal length of the electronic component In addition, it is also preferable to consider the bead apex and the clinch as a set of members and control the complex elastic modulus, which is a parameter indicating rigidity, based on the relationship between the sum of the complex elastic modulus and the longitudinal length of the electronic component.

Specifically, even if the ratio ((70°C E*BA + 70°C E*CA)/L) of the sum of the complex elastic moduli 70°C E ^* BA (MPa) and 70°C E ^* CA (MPa) of the bead apex and clinch measured in tension under conditions of a temperature of 70 ^° C, a frequency ^of 10 Hz, an initial strain of 5% ^, and ^a dynamic strain rate of 1%, to the longitudinal length L (mm) of the electronic component, is controlled to be greater than 0.25, the rigidity can be used to suppress the concentration of strain on the clinch, thereby more appropriately suppressing deformation of the clinch, and it is believed that the durability of the electronic component attached to the tire during driving can be further improved.

6. Electronic Components In the present invention, it is preferable to use an RFID or a sensor as the electronic component, and an RFID is more preferable considering that it can store a large amount of information and can be read without contact, and can store tire manufacturing information, management information, customer information, etc. in addition to data such as pressure and temperature. Specific examples of the sensor include a pressure sensor, a temperature sensor, an acceleration sensor, a magnetic sensor, and a groove depth sensor.

It is also preferable that the surface of the electronic component is provided with an adhesive layer or a plating layer to improve adhesion to the rubber. This can adequately prevent the electronic component from peeling off.

Specific examples of adhesive layers include known metal-rubber adhesives, which can be purchased from LORD Corporation and other companies. The plating layer preferably contains copper, and is preferably alloyed with tin, nickel, iron, zinc, cobalt, aluminum, magnesium, and the like.

It is also preferable that the surface of the electronic component is provided with an electronic component coating layer having a thickness of 0.5 mm or more. In this way, by providing an appropriate gap between the electronic component and the adjacent sidewall portion or carcass layer, the electronic component is less susceptible to the effects of deformation at the interface, and peeling of the electronic component can be sufficiently suppressed.

Specific examples of the electronic component coating layer include rubber compositions and thermoplastic elastomer compositions, such as the rubber compositions described in this specification and rubber compositions known in the tire field.

In the present invention, the longitudinal length L of the electronic component (including the antenna) is preferably 80 mm or less, and more preferably 50 mm or less. This size prevents localized stress concentration and allows the electronic component to be properly aligned and adhered to the tire component, sufficiently preventing peeling.

The product (D1 x W) of the shortest distance D1 (mm) to the outer surface of the tire and the weight W (g) of the electronic component is preferably 2.5 or less. By controlling D1 x W to such a value, deformation around the electronic component can be sufficiently suppressed, and peeling can be suppressed.

In the present invention, taking into consideration the purpose and durability of the electronic component, it is preferable that the ratio (D2/D3) of the distance D2 (mm) from the center position of the electronic component to the bottom end of the bead core in the tire radial direction to the distance D3 (mm) from the maximum tire width position to the bottom end of the bead core is 0.3 or more and 1.7 or less.

In the above, the "center position of the electronic component" refers to the center in the longitudinal direction of the electronic component, the center in the width direction perpendicular to the longitudinal direction, and the center in the height direction perpendicular to both the longitudinal direction and the width direction, and the "bottom end of the bead core" refers to the bottom edge of the bead core in the radial direction of the tire.

7. Shortest distance from electronic components to the tire outer surface (1) As described above, the loss tangent tan δ is a viscoelastic parameter that indicates the energy absorption performance, and the larger the value, the more energy is absorbed, the more heat is generated, and the more deformation occurs. On the other hand, the smaller the distance from the electronic components to the tire outer surface, the easier it is to release heat, and the more heat can be suppressed. Therefore, if the product of the loss tangent of the bead apex and the distance from the electronic components to the tire outer surface can be controlled to a certain value or less, it is possible to sufficiently suppress heat generation in the bead apex that is in contact with the clinch, and more appropriately suppress deformation of the clinch, and it is believed that the durability of the electronic components attached to the tire during running can be further improved.

As a result of various experiments and studies, it is believed that if the product of the loss tangent 70°C tan δBA of the bead apex and D1 (mm) (70°C tan δBA x D1) is 1.5 or less, heat generation in the bead apex can be sufficiently suppressed.

(2) As described above, when the bead apex and the clinch are considered as a set of components, if the product of the sum of the loss tangent 70°C tan δBA of the bead apex and the loss tangent 70°C tan δCA of the clinch (70°C tan δBA + 70°C tan δCA) and D1 (mm) ((70°C tan δBA + 70°C tan δCA) x D1) is 2.5 or less, it is considered that heat generation in the bead apex can be sufficiently suppressed.

(3) On the other hand, it is believed that the larger D1 is, the more the bead apex and clinch will store heat and become more likely to deform. For this reason, it is preferable to increase the complex elastic modulus of the bead apex and clinch to suppress deformation.

Furthermore, as a result of various experiments and considerations, it is believed that if the ratio of the sum of 70°C E ^* BA and 70°C E ^* CA (70°C E ^* CA + 70°C E ^* BA) to D1 ((70°C E ^* CA + 70°C E ^* BA)/D1) is 6.0 or more, deformation of the bead apex and clinch can be sufficiently suppressed.

[3] Embodiments Hereinafter, the present invention will be described in detail based on embodiments.

1. Tire according to the present embodiment Fig. 1 is a schematic cross-sectional view showing the structure of a tire according to an embodiment of the present invention. In Fig. 1, 1 is a tire, 2 is a bead portion, 3 is a sidewall portion, 4 is a tread portion, 31 is a sidewall, 32 is a carcass layer, 33 is an inner liner, and 34 is an electronic component. The carcass layer 32 is folded back from the inner side in the tire width direction to the outer side at the lower end of the bead core 21 along the bead core 21 and the bead apex 22 that constitute the bead portion 2, and then bonded to the inner carcass layer 32. A chafer 24 is provided on the inner side in the tire width direction of the bead portion 2, and a clinch 23 extending to the chafer 24 is provided on the outer side in the tire width direction.

In this embodiment, the electronic component 34 is provided between the carcass layer 32 and the clinch 23. Here, "the electronic component is provided between the carcass layer and the clinch" means that the electronic component is provided between the surfaces opposite to the surfaces where the carcass layer and the clinch are in contact with each other, and also includes the case where the electronic component is embedded in the carcass layer or the clinch.

Figure 2 is a schematic plan view showing the form of the electronic component used in this embodiment, with two examples shown in (a) and (b). As shown in Figures 2 (a) and (b), the electronic component 34 is composed of a main body 34a made of an IC chip and an antenna 34b.

By configuring the tire in this way, and by having the clinch 23, tread portion 4, and bead apex 22 satisfy the above-mentioned parameters, the amount of deformation around the electronic components can be sufficiently reduced, improving the durability of the electronic components attached to the tire during driving.

2. Rubber Composition In the present embodiment, the rubber compositions constituting the clinch, bead apex, and tread (hereinafter, referred to as the "rubber composition for clinch", the "rubber composition for bead apex", and the "rubber composition for tread", respectively) can be obtained by kneading various compounding materials such as a rubber component, a reinforcing material, an antioxidant, oil, a resin material, an antioxidant, and additives.

(1) Compounding Materials (a) Rubber Component In each rubber composition, the rubber component is not particularly limited, and for example, diene rubber such as natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), and butyl rubber (IIR) can be used. These may be used alone, or two or more may be used in combination. For example, in the rubber composition for clinching, it is preferable to use BR and isoprene rubber in combination. And, in the rubber composition for bead apex, it is preferable to use isoprene rubber and SBR in combination, and in the rubber composition for tread, it is preferable to use SBR and BR in combination.

(a) Isoprene-Based Rubber Examples of isoprene-based rubber include natural rubber (NR), isoprene rubber (IR), modified NR, modified NR, and modified IR. Of these, NR is preferred because of its excellent strength.

As the NR, for example, SVR-L, SIR20, RSS#3, TSR20, etc., which are common in the tire industry, can be used. As the IR, there is no particular limitation, and for example, IR2200 manufactured by Zeon Corporation, etc., which are common in the tire industry, can be used. As the modified NR, deproteinized natural rubber (DPNR), high-purity natural rubber (UPNR), etc. can be used. As the modified NR, epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), grafted natural rubber, etc. can be used. As the modified IR, epoxidized isoprene rubber, hydrogenated isoprene rubber, grafted isoprene rubber, etc. can be used. These may be used alone or in combination of two or more.

In the rubber composition for clinching, the content of isoprene-based rubber in 100 parts by mass of the rubber component is preferably 30 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 45 parts by mass or more. On the other hand, it is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 55 parts by mass or less.

In the rubber composition for bead apex, the content of isoprene-based rubber in 100 parts by mass of the rubber component is preferably 30 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 45 parts by mass or more. On the other hand, it is preferably 75 parts by mass or less, more preferably 70 parts by mass or less, and even more preferably 65 parts by mass or less.

In addition, the rubber composition for treads may contain 5 parts by mass or more and 10 parts by mass or less of isoprene-based rubber per 100 parts by mass of the rubber component, if necessary.

(b) Special Branch Office
The weight average molecular weight of SBR is, for example, more than 100,000 and less than 2,000,000. The styrene content of SBR is, for example, preferably more than 5 mass%, more preferably more than 10 mass%, and even more preferably more than 20 mass%. On the other hand, it is preferably less than 50 mass%, more preferably less than 40 mass%, and even more preferably less than 35 mass%. The vinyl content (amount of 1,2-bonded butadiene units) of SBR is, for example, preferably more than 5 mass%, more preferably more than 10 mass%, and even more preferably more than 15 mass%. On the other hand, it is preferably less than 70 mass%, more preferably less than 40 mass%, and even more preferably less than 30 mass%. The structure identification of SBR (measurement of styrene content and vinyl content) can be performed using, for example, a JNM-ECA series device manufactured by JEOL Ltd.

There are no particular limitations on the SBR, and for example, emulsion-polymerized styrene-butadiene rubber (E-SBR), solution-polymerized styrene-butadiene rubber (S-SBR), etc. can be used. The SBR may be either unmodified SBR or modified SBR. Hydrogenated SBR, in which the butadiene portion of SBR is hydrogenated, may also be used. Hydrogenated SBR may be obtained by subsequently hydrogenating the BR portion of SBR, or a similar structure may be obtained by copolymerizing styrene, ethylene, and butadiene.

The modified SBR is preferably an SBR having a functional group that interacts with a filler such as silica. Examples of the modified SBR include terminally modified SBR (terminally modified SBR having the above-mentioned functional group at the terminal) in which at least one terminal of the SBR has been modified with a compound (modifying agent) having the above-mentioned functional group, main-chain modified SBR having the above-mentioned functional group in the main chain, main-chain terminally modified SBR having the above-mentioned functional group in the main chain and at least one terminal (for example, main-chain terminally modified SBR having the above-mentioned functional group in the main chain and at least one terminal modified with the above-mentioned modifying agent), and terminally modified SBR modified (coupled) with a polyfunctional compound having two or more epoxy groups in the molecule and having a hydroxyl group or epoxy group introduced therein.

Examples of the functional groups include amino groups, amide groups, silyl groups, alkoxysilyl groups, isocyanate groups, imino groups, imidazole groups, urea groups, ether groups, carbonyl groups, oxycarbonyl groups, mercapto groups, sulfide groups, disulfide groups, sulfonyl groups, sulfinyl groups, thiocarbonyl groups, ammonium groups, imide groups, hydrazo groups, azo groups, diazo groups, carboxyl groups, nitrile groups, pyridyl groups, alkoxy groups, hydroxyl groups, oxy groups, and epoxy groups. These functional groups may have a substituent.

In addition, the modified SBR may be, for example, SBR modified with a compound (modifier) represented by the following formula:

In the formula, R ¹ , R ² and R ³ are the same or different and represent an alkyl group, an alkoxy group, a silyloxy group, an acetal group, a carboxyl group (-COOH), a mercapto group (-SH) or a derivative thereof. ^{R 4} and R ⁵ are the same or different and represent a hydrogen atom or an alkyl group. R ⁴ and R ⁵ may be bonded to form a ring structure together with the nitrogen atom. n represents an integer.

As modified SBR modified with a compound (modifier) represented by the above formula, SBR in which the polymerization terminals (active terminals) of solution-polymerized styrene-butadiene rubber (S-SBR) have been modified with a compound represented by the above formula (such as the modified SBR described in JP 2010-111753 A).

R ¹ , R ² and R ³ are preferably alkoxy groups (preferably alkoxy groups having 1 to 8 carbon atoms, more preferably alkoxy groups having 1 to 4 carbon atoms). R ⁴ and R ⁵ are preferably alkyl groups (preferably alkyl groups having 1 to 3 carbon atoms). n is preferably 1 to 5, more preferably 2 to 4, and even more preferably 3. When R ⁴ and R ⁵ are combined to form a ring structure together with the nitrogen atom, it is preferably a 4- to 8-membered ring. The alkoxy group also includes cycloalkoxy groups (cyclohexyloxy group, etc.) and aryloxy groups (phenoxy group, benzyloxy group, etc.).

Specific examples of the above-mentioned modifying agent include 2-dimethylaminoethyltrimethoxysilane, 3-dimethylaminopropyltrimethoxysilane, 2-dimethylaminoethyltriethoxysilane, 3-dimethylaminopropyltriethoxysilane, 2-diethylaminoethyltrimethoxysilane, 3-diethylaminopropyltrimethoxysilane, 2-diethylaminoethyltriethoxysilane, 3-diethylaminopropyltriethoxysilane, etc. These may be used alone or in combination of two or more.

In addition, modified SBR modified with the following compounds (modifiers) can also be used as modified SBR. Modifiers include, for example, polyglycidyl ethers of polyhydric alcohols such as ethylene glycol diglycidyl ether, glycerin triglycidyl ether, trimethylolethane triglycidyl ether, and trimethylolpropane triglycidyl ether; polyglycidyl ethers of aromatic compounds having two or more phenol groups, such as diglycidylated bisphenol A; polyepoxy compounds such as 1,4-diglycidylbenzene, 1,3,5-triglycidylbenzene, and polyepoxidized liquid polybutadiene; 4,4'-diglycidyl-diphenylmethylamine, 4,4 Epoxy group-containing tertiary amines such as N,N'-diglycidyl-dibenzylmethylamine; diglycidylamino compounds such as diglycidylaniline, N,N'-diglycidyl-4-glycidyloxyaniline, diglycidylorthotoluidine, tetraglycidylmetaxylenediamine, tetraglycidylaminodiphenylmethane, tetraglycidyl-p-phenylenediamine, diglycidylaminomethylcyclohexane, and tetraglycidyl-1,3-bisaminomethylcyclohexane; bis-(1-methylpropyl)carbamic acid chloride, 4-morpholinecarbonyl chloride, 1 -pyrrolidine carbonyl chloride, N,N-dimethylcarbamic acid chloride, N,N-diethylcarbamic acid chloride, and other amino group-containing acid chlorides; 1,3-bis-(glycidyloxypropyl)-tetramethyldisiloxane, (3-glycidyloxypropyl)-pentamethyldisiloxane, and other epoxy group-containing silane compounds; (trimethylsilyl)[3-(trimethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(triethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(trippropoxysilyl)propyl]sulfide, ( Sulfide group-containing silane compounds such as (trimethylsilyl)[3-(tributoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(methyldimethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(methyldiethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(methyldipropoxysilyl)propyl]sulfide, and (trimethylsilyl)[3-(methyldibutoxysilyl)propyl]sulfide; N-substituted aziridine compounds such as ethyleneimine and propyleneimine; methyltriethoxysilane, N,N-bis(trimethylsilyl)propyl ... alkoxysilanes such as N,N-bis(trimethylsilyl)-3-aminopropyltrimethoxysilane, N,N-bis(trimethylsilyl)-3-aminopropyltriethoxysilane, N,N-bis(trimethylsilyl)aminoethyltrimethoxysilane, and N,N-bis(trimethylsilyl)aminoethyltriethoxysilane; 4-N,N-dimethylaminobenzophenone, 4-N,N-di-t-butylaminobenzophenone, 4-N,N-diphenylaminobenzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4' (thio)benzophenone compounds having an amino group and/or a substituted amino group, such as N,N-bis(diphenylamino)benzophenone and N,N,N',N'-bis-(tetraethylamino)benzophenone; benzaldehyde compounds having an amino group and/or a substituted amino group, such as 4-N,N-dimethylaminobenzaldehyde, 4-N,N-diphenylaminobenzaldehyde and 4-N,N-divinylaminobenzaldehyde; N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-phenyl-2-pyrrolidone, N-t-butyl-2-pyrrolidone, N-methyl N-substituted pyrrolidones such as N-methyl-2-piperidone, N-vinyl-2-piperidone, and N-phenyl-2-piperidone; N-substituted lactams such as N-methyl-ε-caprolactam, N-phenyl-ε-caprolactam, N-methyl-ω-laurylolactam, N-vinyl-ω-laurylolactam, N-methyl-β-propiolactam, and N-phenyl-β-propiolactam; as well as N,N-bis-(2,3-epoxypropoxy)-aniline, 4,4-methylene-bis-(N,N-glycidylaniline), triphenylamine, ... Examples of the compound include 1,3-bis(diphenylamino)-2-propanone, 1,7-bis(methylethylamino)-4-heptanone, and the like. Modification with the above compounds (modifiers) can be carried out by known methods.

As the SBR, for example, SBR manufactured and sold by Sumitomo Chemical Co., Ltd., ENEOS Materials Corporation, Asahi Kasei Corporation, Zeon Corporation, etc. can be used. Note that SBR may be used alone or in combination of two or more types.

In the rubber composition for bead apex, the content of SBR in 100 parts by mass of the rubber component is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, and even more preferably 35 parts by mass or more. On the other hand, it is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 55 parts by mass or less.

In the rubber composition for treads, the content of SBR in 100 parts by mass of the rubber component is preferably 60 parts by mass or more, and more preferably 70 parts by mass or more. There is no particular upper limit, but it is preferably 95 parts by mass or less, and more preferably 90 parts by mass or less.

In addition, the clinch rubber composition may contain 1 part by mass or more and less than 10 parts by mass of SBR per 100 parts by mass of the rubber component, if necessary.

(C) BR
The weight average molecular weight of the BR is, for example, more than 100,000 and less than 2,000,000. The vinyl content of the BR is, for example, more than 1 mass% and less than 30 mass%. The cis content of the BR is, for example, more than 1 mass% and 98 mass% or less. The trans content of the BR is, for example, more than 1 mass% and less than 60 mass%. The cis content can be measured by infrared absorption spectroscopy.

The BR is not particularly limited, and can be BR with a high cis content (cis content of 90% or more), BR with a low cis content, BR containing syndiotactic polybutadiene crystals, etc. The BR can be either unmodified BR or modified BR, and the modified BR can be, for example, BR modified with a compound (modifier) represented by the following formula.

In the formula, R ¹ , R ² and R ³ are the same or different and represent an alkyl group, an alkoxy group, a silyloxy group, an acetal group, a carboxyl group (-COOH), a mercapto group (-SH) or a derivative thereof. ^{R 4} and R ⁵ are the same or different and represent a hydrogen atom or an alkyl group. R ⁴ and R ⁵ may be bonded to form a ring structure together with the nitrogen atom. n represents an integer.

The modified BR modified with the compound (modifier) represented by the above formula can be BR whose polymerization end (active end) has been modified with the compound represented by the above formula.

R ¹ , R ² and R ³ are preferably alkoxy groups (preferably alkoxy groups having 1 to 8 carbon atoms, more preferably alkoxy groups having 1 to 4 carbon atoms). R ⁴ and R ⁵ are preferably alkyl groups (preferably alkyl groups having 1 to 3 carbon atoms). n is preferably 1 to 5, more preferably 2 to 4, and even more preferably 3. When R ⁴ and R ⁵ are combined to form a ring structure together with the nitrogen atom, it is preferably a 4- to 8-membered ring. The alkoxy group also includes cycloalkoxy groups (cyclohexyloxy group, etc.) and aryloxy groups (phenoxy group, benzyloxy group, etc.).

Specific examples of the above-mentioned modifying agent include 2-dimethylaminoethyltrimethoxysilane, 3-dimethylaminopropyltrimethoxysilane, 2-dimethylaminoethyltriethoxysilane, 3-dimethylaminopropyltriethoxysilane, 2-diethylaminoethyltrimethoxysilane, 3-diethylaminopropyltrimethoxysilane, 2-diethylaminoethyltriethoxysilane, 3-diethylaminopropyltriethoxysilane, etc. These may be used alone or in combination of two or more.

In addition, modified BR modified with the following compounds (modifiers) can also be used as modified BR. Modifiers include, for example, polyglycidyl ethers of polyhydric alcohols such as ethylene glycol diglycidyl ether, glycerin triglycidyl ether, trimethylolethane triglycidyl ether, and trimethylolpropane triglycidyl ether; polyglycidyl ethers of aromatic compounds having two or more phenol groups such as diglycidylated bisphenol A; polyepoxy compounds such as 1,4-diglycidylbenzene, 1,3,5-triglycidylbenzene, and polyepoxidized liquid polybutadiene; 4,4'-diglycidyl-diphenylmethylamine, 4,4 Epoxy group-containing tertiary amines such as N,N'-diglycidyl-dibenzylmethylamine; diglycidylamino compounds such as diglycidylaniline, N,N'-diglycidyl-4-glycidyloxyaniline, diglycidylorthotoluidine, tetraglycidylmetaxylenediamine, tetraglycidylaminodiphenylmethane, tetraglycidyl-p-phenylenediamine, diglycidylaminomethylcyclohexane, and tetraglycidyl-1,3-bisaminomethylcyclohexane; bis-(1-methylpropyl)carbamic acid chloride, 4-morpholinecarbonyl chloride, 1 -pyrrolidine carbonyl chloride, N,N-dimethylcarbamic acid chloride, N,N-diethylcarbamic acid chloride, and other amino group-containing acid chlorides; 1,3-bis-(glycidyloxypropyl)-tetramethyldisiloxane, (3-glycidyloxypropyl)-pentamethyldisiloxane, and other epoxy group-containing silane compounds; (trimethylsilyl)[3-(trimethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(triethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(trippropoxysilyl)propyl]sulfide, ( Sulfide group-containing silane compounds such as (trimethylsilyl)[3-(tributoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(methyldimethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(methyldiethoxysilyl)propyl]sulfide, (trimethylsilyl)[3-(methyldipropoxysilyl)propyl]sulfide, and (trimethylsilyl)[3-(methyldibutoxysilyl)propyl]sulfide; N-substituted aziridine compounds such as ethyleneimine and propyleneimine; methyltriethoxysilane, N,N-bis(trimethylsilyl)propyl ... alkoxysilanes such as N,N-bis(trimethylsilyl)-3-aminopropyltrimethoxysilane, N,N-bis(trimethylsilyl)-3-aminopropyltriethoxysilane, N,N-bis(trimethylsilyl)aminoethyltrimethoxysilane, and N,N-bis(trimethylsilyl)aminoethyltriethoxysilane; 4-N,N-dimethylaminobenzophenone, 4-N,N-di-t-butylaminobenzophenone, 4-N,N-diphenylaminobenzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4' (thio)benzophenone compounds having an amino group and/or a substituted amino group, such as N,N-bis(diphenylamino)benzophenone and N,N,N',N'-bis-(tetraethylamino)benzophenone; benzaldehyde compounds having an amino group and/or a substituted amino group, such as 4-N,N-dimethylaminobenzaldehyde, 4-N,N-diphenylaminobenzaldehyde and 4-N,N-divinylaminobenzaldehyde; N-methyl-2-pyrrolidone, N-vinyl-2-pyrrolidone, N-phenyl-2-pyrrolidone, N-t-butyl-2-pyrrolidone, N-methyl N-substituted pyrrolidones such as N-methyl-5-methyl-2-pyrrolidone; N-substituted piperidones such as N-methyl-2-piperidone, N-vinyl-2-piperidone, and N-phenyl-2-piperidone; N-substituted lactams such as N-methyl-ε-caprolactam, N-phenyl-ε-caprolactam, N-methyl-ω-laurylolactam, N-vinyl-ω-laurylolactam, N-methyl-β-propiolactam, and N-phenyl-β-propiolactam; as well as N,N-bis-(2,3-epoxypropoxy)-aniline, 4,4-methylene-bis-(N,N-glycidylaniline), tetrahydrofuran, ... Examples of the modified BR include thi-(2,3-epoxypropyl)-1,3,5-triazine-2,4,6-triones, N,N-diethylacetamide, N-methylmaleimide, N,N-diethylurea, 1,3-dimethylethyleneurea, 1,3-divinylethyleneurea, 1,3-diethyl-2-imidazolidinone, 1-methyl-3-ethyl-2-imidazolidinone, 4-N,N-dimethylaminoacetophene, 4-N,N-diethylaminoacetophenone, 1,3-bis(diphenylamino)-2-propanone, and 1,7-bis(methylethylamino)-4-heptanone. The modification with the above-mentioned compound (modifier) can be carried out by a known method. These modified BRs may be used alone or in combination of two or more.

As BR, products from, for example, Ube Industries, Ltd., ENEOS Materials, Inc., Asahi Kasei Corporation, Zeon Corporation, etc. can be used.

In the rubber composition for clinching, the content of BR in 100 parts by mass of the rubber component is preferably 30 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 45 parts by mass or more. On the other hand, it is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 55 parts by mass or less.

In the rubber composition for treads, the content of BR in 100 parts by mass of the rubber component is preferably 5 parts by mass or more, and more preferably 10 parts by mass or more. On the other hand, it is preferably 40 parts by mass or less, and more preferably 30 parts by mass or less.

In addition, the rubber composition for the bead apex may contain 1 part by mass or more and less than 10 parts by mass of BR per 100 parts by mass of the rubber component, if necessary.

(d) Other Rubber Components In the present embodiment, each rubber composition may contain, as other rubber components, rubber (polymer) that is generally used in the manufacture of tires, such as nitrile rubber (NBR).

(b) Compounding materials other than rubber components (a) Filler In this embodiment, each rubber composition preferably contains a reinforcing agent such as carbon black or silica as a filler. In addition to the above-mentioned carbon black and silica, examples of the filler include calcium carbonate, talc, alumina, clay, aluminum hydroxide, mica, etc. In addition, when silica is used, it is preferable to use it in combination with a silane coupling agent.

In any rubber composition, the total amount of filler is preferably 40 parts by mass or more, and more preferably 50 parts by mass or more, per 100 parts by mass of the rubber component. On the other hand, from the viewpoint of dispersibility in the rubber composition, it is preferably 150 parts by mass or less, and more preferably 140 parts by mass or less.

(i) Carbon Black Carbon black is used for the purpose of improving the crack growth resistance, durability, resistance to deterioration due to ultraviolet light, etc. of tires.

The nitrogen adsorption specific surface area (N ₂ SA) of carbon black is, for example, preferably 30 m ² /g or more, more preferably 50 m ² /g or more, and even more preferably 60 m ² /g or more, from the viewpoint of reinforcing the rubber. On the other hand, from the viewpoint of heat generation, it is preferably 250 m ² /g or less, more preferably 150 m ² /g, and even more preferably 120 m ² /g or less. From the viewpoint of rubber rigidity, the dibutyl phthalate (DBP) absorption amount of carbon black is, for example, preferably 50 ml/100 g or more, and more preferably 100 ml/100 g or more. On the other hand, from the viewpoint of rubber deformation followability, it is preferably 250 ml/100 g or less, and more preferably 150 ml/100 g or less. The nitrogen adsorption specific surface area of carbon black is measured in accordance with ASTM D4820-93, and the DBP absorption amount is measured in accordance with ASTM D2414-93.

Carbon black is not particularly limited, and examples thereof include furnace blacks (furnace carbon blacks) such as SAF, ISAF, HAF, MAF, FEF, SRF, GPF, APF, FF, CF, SCF, and ECF; acetylene black (acetylene carbon black); thermal blacks (thermal carbon blacks) such as FT and MT; and channel blacks (channel carbon blacks) such as EPC, MPC, and CC. These may be used alone or in combination of two or more. Among these, FEF is preferred from the viewpoint of extrusion processability and impact absorption.

Specific carbon blacks are not particularly limited, and examples include N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, and N762. Commercially available products include those from Asahi Carbon Co., Ltd., Cabot Japan Co., Ltd., Tokai Carbon Co., Ltd., Mitsubishi Chemical Corporation, Lion Corporation, Shinnikka Carbon Co., Ltd., Columbia Carbon Co., Ltd., and the like. These may be used alone or in combination of two or more types.

In the rubber composition for clinching, the carbon black content per 100 parts by mass of the rubber component is, for example, preferably 10 parts by mass or more, more preferably 30 parts by mass or more, and even more preferably 35 parts by mass or more. On the other hand, it is preferably 100 parts by mass or less, more preferably 90 parts by mass or less, and even more preferably 80 parts by mass or less.

In the rubber composition for bead apex, the carbon black content per 100 parts by mass of the rubber component is preferably 40 parts by mass or more, and more preferably 50 parts by mass or more. On the other hand, it is preferably 100 parts by mass or less, and more preferably 80 parts by mass or less.

In addition, in the rubber composition for treads, the content of carbon black per 100 parts by mass of the rubber component is preferably 5 parts by mass or more, and more preferably 10 parts by mass or more. On the other hand, it is preferably 50 parts by mass or less, and more preferably 40 parts by mass or less.

(ii) Silica Since silica is not conductive, when used as a reinforcing material, it can reduce the dielectric constant and expand the reading range of electronic components. In addition, the hydrated water and surface functional groups contained in silica can capture ozone, improving ozone resistance and improving the durability of tires.

When the average primary particle size of silica is too small, the processability is poor, so it is preferable to use silica having an average primary particle size of more than 8 nm. 9 nm or more is more preferable, and 10 nm or more is even more preferable. On the other hand, from the viewpoint of ensuring the reinforcement of the rubber and ensuring the steering stability performance on wet road surfaces during driving, it is preferable that the average primary particle size is 25 nm or less, more preferably 20 nm or less, and even more preferably 17 nm or less.

The average primary particle size of silica refers to the average value of the smallest particle unit of silica that constitutes the aggregate structure, observed as a circle, and the absolute maximum length of the smallest particle measured as the diameter of the circle. It can be obtained by observing with a transmission or scanning electron microscope, measuring 400 or more primary particles of silica observed within the field of view, and averaging the measurements.

From the viewpoint of obtaining good durability, the BET specific surface area of the silica is preferably more than 100 m ² /g, more preferably more than 130 m ² /g, and is preferably less than 250 m ² /g, more preferably less than 200 m ² /g. The BET specific surface area is the N ₂ SA value measured by the BET method according to ASTM D3037-93.

Examples of silica include dry process silica (anhydrous silica), wet process silica (hydrated silica), and colloidal silica. Among them, wet process silica is preferred because it contains water of hydration and a large number of silanol groups, and can effectively capture ozone. In addition, silica made from hydrous glass or silica made from biomass materials such as rice husks may also be used.

As silica, products from Evonik Industries, Rhodia, Tosoh Silica, Solvay Japan, Tokuyama, etc. can be used.

In the rubber composition for treads, the content of silica per 100 parts by mass of the rubber component is preferably 40 parts by mass or more, and more preferably 50 parts by mass or more, per 100 parts by mass of the rubber component. On the other hand, from the viewpoint of dispersibility in the rubber composition, the content is preferably 110 parts by mass or less, and more preferably 100 parts by mass or less.

In the rubber composition for clinching, the content of BR in 100 parts by mass of the rubber component is preferably 5 parts by mass or more, and more preferably 10 parts by mass or more. On the other hand, it is preferably 40 parts by mass or less, and more preferably 30 parts by mass or less.

The rubber composition for clinch and the rubber composition for bead apex may contain silica as necessary. In this case, in consideration of sufficient extrusion processability and ozone resistance, the content of silica per 100 parts by mass of rubber component is, for example, preferably 5 parts by mass or more, and more preferably 10 parts by mass or more. Also, it is preferably 20 parts by mass or less, and more preferably 15 parts by mass or less. By using such an amount of silica, sufficient extrusion processability and ozone resistance can be obtained.

(iii) Silane Coupling Agent When silica is used as a filler, it is preferable to use a silane coupling agent in combination in order to increase the dispersibility of the silica and to improve mechanical properties and moldability by reacting with the silica.

The silane coupling agent is not particularly limited, and examples thereof include bis(3-triethoxysilylpropyl)tetrasulfide, bis(2-triethoxysilylethyl)tetrasulfide, bis(4-triethoxysilylbutyl)tetrasulfide, bis(3-trimethoxysilylpropyl)tetrasulfide, bis(2-trimethoxysilylethyl)tetrasulfide, bis(2-triethoxysilylethyl)trisulfide, bis(4-trimethoxysilylbutyl)trisulfide, Sulfide, bis(3-triethoxysilylpropyl) disulfide, bis(2-triethoxysilylethyl) disulfide, bis(4-triethoxysilylbutyl) disulfide, bis(3-trimethoxysilylpropyl) disulfide, bis(2-trimethoxysilylethyl) disulfide, bis(4-trimethoxysilylbutyl) disulfide, 3-trimethoxysilylpropyl-N,N-dimethylthiocarbamoyl tetrasulfide, 2-triethoxysilyl Examples of suitable coupling agents include sulfide-based coupling agents such as ethyl-N,N-dimethylthiocarbamoyl tetrasulfide and 3-triethoxysilylpropyl methacrylate monosulfide; mercapto-based coupling agents such as 3-mercaptopropyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, and Momentive's NXT and NXT-Z; vinyl-based coupling agents such as vinyltriethoxysilane and vinyltrimethoxysilane; amino-based coupling agents such as 3-aminopropyltriethoxysilane and 3-aminopropyltrimethoxysilane; glycidoxy-based coupling agents such as γ-glycidoxypropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane; nitro-based coupling agents such as 3-nitropropyltrimethoxysilane and 3-nitropropyltriethoxysilane; and chloro-based coupling agents such as 3-chloropropyltrimethoxysilane and 3-chloropropyltriethoxysilane. Among these, preferred are silane coupling agents having a thiocarbonyl group such as the above-mentioned NXT. These may be used alone or in combination of two or more.

Examples of silane coupling agents that can be used include products from Evonik Industries, Momentive, Shin-Etsu Silicones, Tokyo Chemical Industry, Azumax, and Dow Corning Toray.

The content of the silane coupling agent is, for example, preferably more than 3 parts by mass, and more preferably 5 parts by mass or more, relative to 100 parts by mass of silica. On the other hand, it is preferably less than 15 parts by mass, and more preferably 10 parts by mass or less.

(iv) Other Fillers Each rubber composition may further contain, in addition to the above-mentioned carbon black and silica, fillers generally used in the tire industry, such as graphite, calcium carbonate, talc, alumina, clay, aluminum hydroxide, mica, magnesium sulfate, etc. The content of these fillers is, for example, more than 0.1 parts by mass and less than 150 parts by mass per 100 parts by mass of the rubber component.

(b) Plasticizer component In consideration of proper dispersion of powder materials during kneading, it is preferable to use a plasticizer component in each rubber composition as necessary. The plasticizer component here refers to a component that plasticizes the rubber composition, such as process oil, rubber component expander oil, liquid rubber, or resin component.

In the rubber composition for clinch and the rubber composition for bead apex, the content of the plasticizer component per 100 parts by mass of the rubber component is preferably more than 5 parts by mass, more preferably more than 10 parts by mass, and even more preferably more than 12 parts by mass. On the other hand, it is preferably less than 30 parts by mass, more preferably less than 20 parts by mass, and even more preferably less than 17 parts by mass.

In the rubber composition for treads, the content of the plasticizer component per 100 parts by mass of the rubber component is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, and even more preferably 40 parts by mass or more. On the other hand, the upper limit is not particularly limited, but is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 50 parts by mass or less.

The plasticizer content also includes the amount of oil contained in rubber (oil-extended rubber), etc.

(i) Oil Examples of the oil include mineral oil, vegetable oil, and mixtures thereof. Among these, vegetable oil is preferably used because it has a high molecular weight and is therefore more likely to be inhibited from migrating at the rubber layer interface, etc.

Examples of mineral oils include paraffin-based process oils, aromatic process oils, and naphthenic process oils. For example, products from Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo Co., Ltd., ENEOS Corporation, Orisoi Corporation, H&R Corporation, Toyokuni Seiyu Co., Ltd., Showa Shell Sekiyu K.K., Fuji Kosan Co., Ltd., etc. can be used. These may be used alone or in combination of two or more types.

From the perspective of life cycle assessment, these oils may be appropriately refined and used, such as lubricating oils used in the mixers and engines of rubber mixers, or waste cooking oils used in restaurants, etc.

Examples of vegetable oils include linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice oil, tall oil, sesame oil, perilla oil, castor oil, paulownia oil, pine oil, pine tar oil, sunflower oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, and wood wax.

Further examples of vegetable oils include refined oils (such as salad oils) obtained by refining the above oils, transesterified oils obtained by transesterification, hardened oils obtained by hydrogenation, thermally polymerized oils obtained by thermal polymerization, oxidatively polymerized oils obtained by oxidation, and waste edible oils obtained by recovering oils that have been used as edible oils, etc. The vegetable oils may be liquid or solid at room temperature (25°C). These may be used alone or in combination of two or more types.

As the vegetable oil, acylglycerol is preferred, and triacylglycerol is more preferred. Incidentally, acylglycerol refers to a compound in which a hydroxyl group of glycerin and a carboxylic acid are ester-bonded. There are no particular limitations on the acylglycerol, and it may be 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, or triacylglycerol. Furthermore, acylglycerol may be a monomer, a dimer, or a polymer of trimer or more. Incidentally, dimer or more acylglycerols can be obtained by thermal polymerization, oxidative polymerization, or the like. Also, acylglycerol may be liquid or solid at room temperature (25°C).

The method for confirming whether or not acylglycerol is contained in the rubber composition is not particularly limited, but can be confirmed by ¹ H-NMR measurement. For example, a rubber composition containing triacylglycerol is immersed in deuterated chloroform at room temperature (25° C.) for 24 hours, the rubber composition is removed, and then ¹ H-NMR is measured at room temperature. When the signal of tetramethylsilane (TMS) is set to 0.00 ppm, signals are observed around 5.26 ppm, around 4.28 ppm, and around 4.15 ppm. These signals are presumed to be signals derived from hydrogen atoms bonded to carbon atoms adjacent to the oxygen atoms of the ester groups, and therefore the inclusion of acylglycerol can be confirmed. Here, "around" refers to a range of ±0.10 ppm.

The carboxylic acid is not particularly limited and may be either an unsaturated fatty acid or a saturated fatty acid. Examples of unsaturated fatty acids include monounsaturated fatty acids such as oleic acid, and polyunsaturated fatty acids such as linoleic acid and linolenic acid.

As vegetable oils, for example, those commercially available from Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo Co., Ltd., ENEOS Corporation, Orisoi Co., Ltd., H&R Corporation, Toyokuni Oil Mills Co., Ltd., Fuji Kosan Co., Ltd., Nisshin Oillio Group Co., Ltd., etc. can be used.

(ii) Liquid Rubber Liquid rubber is a polymer that is in a liquid state at room temperature (25° C.) and is a rubber component that can be extracted by acetone extraction from a vulcanized tire. Examples of liquid rubber include farnesene-based polymers, liquid diene-based polymers, and hydrogenated products thereof.

Farnesene polymers are polymers obtained by polymerizing farnesene and contain structural units based on farnesene. Farnesene has isomers such as α-farnesene ((3E,7E)-3,7,11-trimethyl-1,3,6,10-dodecatetraene) and β-farnesene (7,11-dimethyl-3-methylene-1,6,10-dodecatriene).

The farnesene-based polymer may be a homopolymer of farnesene (farnesene homopolymer) or a copolymer of farnesene and a vinyl monomer (farnesene-vinyl monomer copolymer).

Examples of liquid diene polymers include liquid styrene-butadiene copolymer (liquid SBR), liquid butadiene polymer (liquid BR), liquid isoprene polymer (liquid IR), liquid styrene-isoprene copolymer (liquid SIR), etc.

The liquid diene polymer has a weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of, for example, more than 1.0 × 10 ³ and less than 2.0 × 10 ^5. Here, the Mw of the liquid diene polymer is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

The content of liquid rubber (total content of liquid farnesene-based polymer, liquid diene-based polymer, etc.) in each rubber composition is preferably, for example, more than 1 part by mass and less than 100 parts by mass per 100 parts by mass of the rubber component.

As liquid rubber, for example, products from Kuraray Co., Ltd., Cray Valley, Inc., etc. can be used.

(iii) Resin component The resin component also functions as a tackifier, and may be solid or liquid at room temperature. Specific examples of the resin component include rosin resin, styrene resin, coumarone resin, terpene resin, C5 resin, C9 resin, C5C9 resin, acrylic resin, etc., and two or more of them may be used in combination. The content of the resin component in each rubber composition is preferably more than 2 parts by mass and less than 45 parts by mass, more preferably less than 30 parts by mass, per 100 parts by mass of the rubber component.

Rosin resins are resins whose main component is rosin acid obtained by processing pine resin. These rosin resins (rosins) can be classified according to whether they have been modified or not, and can be divided into unmodified rosin (unmodified rosin) and modified rosin (rosin derivatives). Examples of unmodified rosins include tall rosin (also known as tall oil rosin), gum rosin, wood rosin, disproportionated rosin, polymerized rosin, hydrogenated rosin, and other chemically modified rosins. Modified rosin is a modification of unmodified rosin, and examples of such modifications include rosin esters, unsaturated carboxylic acid modified rosin esters, unsaturated carboxylic acid modified rosin esters, rosin amide compounds, and rosin amine salts.

Styrene-based resins are polymers that use styrene-based monomers as constituent monomers, and examples thereof include polymers in which styrene-based monomers are polymerized as the main component (50% by mass or more). Specifically, examples include homopolymers in which styrene-based monomers (styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-methoxystyrene, p-tert-butylstyrene, p-phenylstyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, etc.) are polymerized alone, copolymers in which two or more styrene-based monomers are copolymerized, and copolymers of styrene-based monomers and other monomers that can be copolymerized with them.

Examples of the other monomers include acrylonitriles such as acrylonitrile and methacrylonitrile, unsaturated carboxylic acids such as acrylics and methacrylic acid, unsaturated carboxylic acid esters such as methyl acrylate and methyl methacrylate, dienes such as chloroprene and butadiene-isoprene, olefins such as 1-butene and 1-pentene, α,β-unsaturated carboxylic acids such as maleic anhydride or their acid anhydrides, etc.

Among the coumarone resins, coumarone-indene resins are preferred. Coumarone-indene resins are resins that contain coumarone and indene as monomer components that make up the resin skeleton (main chain). Other monomer components contained in the skeleton besides coumarone and indene include styrene, α-methylstyrene, methylindene, vinyltoluene, etc.

In each rubber composition, the content of the coumarone-indene resin is preferably, for example, more than 1.0 part by mass and less than 50.0 parts by mass per 100 parts by mass of the rubber component.

The hydroxyl value (OH value) of the coumarone-indene resin is, for example, more than 15 mgKOH/g and less than 150 mgKOH/g. The OH value is the amount of potassium hydroxide, expressed in milligrams, required to neutralize the acetic acid bonded to the hydroxyl group when acetylating 1 g of resin, and is a value measured by potentiometric titration (JIS K 0070:1992).

The softening point of coumarone-indene resin is, for example, more than 30°C and less than 160°C. The softening point is the temperature at which the ball drops when the softening point as specified in JIS K 6220-1:2001 is measured using a ring and ball softening point tester.

Examples of terpene resins include polyterpene, terpene phenol, and aromatic modified terpene resin. Polyterpene is a resin obtained by polymerizing a terpene compound and a hydrogenated product thereof. Terpene compounds are hydrocarbons represented by the composition (C ₅ H ₈ ) _n and their oxygen-containing derivatives, and are compounds having a basic skeleton of a terpene classified into monoterpene (C ₁₀ H ₁₆ ), sesquiterpene (C ₁₅ H ₂₄ ), diterpene (C ₂₀ H ₃₂ ), etc. Examples of such compounds include α-pinene, β-pinene, dipentene, limonene, myrcene, alloocimene, ocimene, α-phellandrene, α-terpinene, γ-terpinene, terpinolene, 1,8-cineole, 1,4-cineole, α-terpineol, β-terpineol, and γ-terpineol.

Examples of polyterpenes include terpene resins such as α-pinene resin, β-pinene resin, limonene resin, dipentene resin, and β-pinene/limonene resin, which are made from the above-mentioned terpene compounds, as well as hydrogenated terpene resins obtained by hydrogenating the terpene resins. Examples of terpene phenols include resins obtained by copolymerizing the above-mentioned terpene compounds with phenolic compounds, and resins obtained by hydrogenating the above-mentioned resins, specifically resins obtained by condensing the above-mentioned terpene compounds, phenolic compounds, and formalin. Examples of phenolic compounds include phenol, bisphenol A, cresol, and xylenol. Examples of aromatic modified terpene resins include resins obtained by modifying terpene resins with aromatic compounds, and resins obtained by hydrogenating the above-mentioned resins. The aromatic compound is not particularly limited as long as it has an aromatic ring, but examples thereof include phenolic compounds such as phenol, alkylphenols, alkoxyphenols, and phenols containing unsaturated hydrocarbon groups; naphthol compounds such as naphthol, alkylnaphthols, alkoxynaphthols, and naphthols containing unsaturated hydrocarbon groups; styrene derivatives such as styrene, alkylstyrenes, alkoxystyrenes, and styrenes containing unsaturated hydrocarbon groups; coumarone, indene, and the like.

"C5 resin" refers to a resin obtained by polymerizing a C5 fraction. Examples of C5 fractions include petroleum fractions with 4 to 5 carbon atoms, such as cyclopentadiene, pentene, pentadiene, and isoprene. Dicyclopentadiene resin (DCPD resin) is preferably used as a C5 petroleum resin.

"C9 resin" refers to a resin obtained by polymerizing a C9 fraction, and may be a resin obtained by hydrogenating or modifying the C9 fraction. Examples of C9 fractions include petroleum fractions having 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, indene, and methylindene. Specific examples of suitable resins include coumarone-indene resin, coumarone resin, indene resin, and aromatic vinyl resin. As aromatic vinyl resins, α-methylstyrene (AMS resin) or a homopolymer of styrene or a copolymer of α-methylstyrene and styrene is preferred, and a copolymer of α-methylstyrene and styrene is more preferred, because they are economical, easy to process, and have excellent heat generation properties. As aromatic vinyl resins, for example, those commercially available from Kraton, Eastman Chemical, etc. can be used.

"C5C9 resin" refers to a resin obtained by copolymerizing the C5 fraction and the C9 fraction, and may be a resin that has been hydrogenated or modified. Examples of the C5 fraction and the C9 fraction include the petroleum fractions mentioned above. As the C5C9 resin, for example, those commercially available from Tosoh Corporation, LUHUA Corporation, etc. can be used.

There are no particular limitations on the acrylic resin, but for example, a solvent-free acrylic resin can be used.

Examples of solvent-free acrylic resins include (meth)acrylic resins (polymers) synthesized by high-temperature continuous polymerization (high-temperature continuous bulk polymerization) (methods described in U.S. Pat. No. 4,414,370, JP-A-59-6207, JP-B-5-58005, JP-A-1-313522, U.S. Pat. No. 5,010,166, and Toa Gosei Kenkyuu Nenpo TREND 2000 Vol. 3, p. 42-45, etc.) with minimal use of secondary raw materials such as polymerization initiators, chain transfer agents, and organic solvents. In the present invention, (meth)acrylic means methacryl and acrylic.

Examples of monomer components constituting the acrylic resin include (meth)acrylic acid, (meth)acrylic acid esters (alkyl esters, aryl esters, aralkyl esters, etc.), (meth)acrylamide, and (meth)acrylic acid derivatives such as (meth)acrylamide derivatives.

In addition, aromatic vinyls such as styrene, α-methylstyrene, vinyltoluene, vinylnaphthalene, divinylbenzene, trivinylbenzene, and divinylnaphthalene may be used together with (meth)acrylic acid or (meth)acrylic acid derivatives as monomer components constituting the above acrylic resin.

The acrylic resin may be a resin composed only of (meth)acrylic components, or a resin containing components other than the (meth)acrylic component. The acrylic resin may also have a hydroxyl group, a carboxyl group, a silanol group, etc.

As the resin component, for example, products from Maruzen Petrochemical Co., Ltd., Sumitomo Bakelite Co., Ltd., Yasuhara Chemical Co., Ltd., Tosoh Corporation, Rutgers Chemicals, BASF, Clayton, Nippon Paint Chemical Co., Ltd., Nippon Shokubai Co., Ltd., ENEOS Corporation, Arakawa Chemical Industries Co., Ltd., Taoka Chemical Co., Ltd., etc. can be used.

(C) Curable Resin Component Each rubber composition preferably contains a curable resin component such as a modified resorcinol resin or modified phenolic resin as a heat resistance improver in order to suppress changes in E ^* at high temperatures.

Specific examples of modified resorcinol resins include Sumikanol 620 (modified resorcinol resin) manufactured by Taoka Chemical Co., Ltd., and examples of modified phenolic resins include PR12686 (cashew oil modified phenolic resin) manufactured by Sumitomo Bakelite Co., Ltd.

The content of the curable resin component is preferably 1 part by mass or more, and more preferably 2 parts by mass or more, per 100 parts by mass of the rubber component, from the viewpoint of sufficiently improving the complex elastic modulus and obtaining a large reaction force during deformation. On the other hand, from the viewpoint of maintaining the breaking strength, the content is preferably 10 parts by mass or less, and more preferably 8 parts by mass or less.

When using modified resorcinol resin, it is preferable to also contain a methylene donor as a curing agent. Examples of methylene donors include hexamethylenetetramine (HMT), hexamethoxymethylolmelamine (HMMM), and hexamethylolmelamine pentamethylether (HMMPME), and it is preferable to contain, for example, 5 parts by mass or more, and about 15 parts by mass, per 100 parts by mass of the curable resin component. If the amount is too small, there is a risk that a sufficient complex modulus of elasticity cannot be obtained. On the other hand, if the amount is too large, there is a risk that the viscosity of the rubber increases and the processability deteriorates.

Specific examples of methylene donors that can be used include Sumikanol 507 manufactured by Taoka Chemical Co., Ltd.

(D) Lubricant (stearic acid)
Each rubber composition may contain a lubricant. As the lubricant, a lubricant based on a fatty acid derivative such as stearic acid can be preferably used. As the stearic acid, a conventionally known lubricant can be used, specifically, for example, products of NOF Corporation, NOF Corporation, Kao Corporation, Fujifilm Wako Pure Chemical Industries, Ltd., Chiba Fatty Acid Co., Ltd., etc. can be used. In addition, Struktol WB16 manufactured by Struktol Co., Ltd. can also be used.

The content of stearic acid is preferably, for example, more than 0.5 parts by mass and less than 10.0 parts by mass per 100 parts by mass of the rubber component.

(e) Antiaging Agent Each rubber composition may contain an antiaging agent. The content of the antiaging agent per 100 parts by mass of the rubber component is, for example, more than 1 part by mass and less than 10 parts by mass.

Examples of the anti-aging agents include naphthylamine-based anti-aging agents such as phenyl-α-naphthylamine; diphenylamine-based anti-aging agents such as octylated diphenylamine and 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine; N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, and N,N'-di-2-naphthyl-p-phenylenediamine. p-phenylenediamine-based antioxidants such as quinolinol; quinoline-based antioxidants such as polymers of 2,2,4-trimethyl-1,2-dihydroquinoline; monophenol-based antioxidants such as 2,6-di-t-butyl-4-methylphenol and styrenated phenol; and bis-, tris-, and polyphenol-based antioxidants such as tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane. These may be used alone or in combination of two or more.

Specific examples of anti-aging agents that can be used include products from Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinko Chemical Co., Ltd., Flexis, etc.

(F) Zinc oxide Each rubber composition may contain zinc oxide. The content of zinc oxide is, for example, more than 0.5 parts by mass and less than 10 parts by mass per 100 parts by mass of the rubber component. As the zinc oxide, a conventionally known product can be used, and for example, products of Mitsui Mining & Smelting Co., Ltd., Toho Zinc Co., Ltd., Hakusui Tech Co., Ltd., Seido Chemical Industry Co., Ltd., Sakai Chemical Industry Co., Ltd., etc. can be used.

(G) Wax Each rubber composition may contain wax. The content of the wax relative to 100 parts by mass of the rubber component is, for example, preferably 0.5 to 20 parts by mass, more preferably 1.0 to 15 parts by mass, and further preferably 1.5 to 10 parts by mass.

The wax is not particularly limited, and examples thereof include petroleum waxes such as paraffin wax and microcrystalline wax; natural waxes such as vegetable wax and animal wax; and synthetic waxes such as polymers of ethylene, propylene, etc. These may be used alone or in combination of two or more kinds.

As wax, products from Ouchi Shinko Chemical Industry Co., Ltd., Nippon Seiro Co., Ltd., Seiko Chemical Co., Ltd., etc. can be used.

(H) Crosslinking agent and vulcanization accelerator Each rubber composition preferably contains a crosslinking agent such as sulfur. The content of the crosslinking agent is, for example, more than 0.1 parts by mass and less than 10.0 parts by mass per 100 parts by mass of the rubber component. The sulfur content is the pure sulfur content, and in the case of using insoluble sulfur, it is the content excluding the oil content.

Examples of sulfur include powdered sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, highly dispersible sulfur, and soluble sulfur, which are commonly used in the rubber industry. These may be used alone or in combination of two or more types.

As sulfur, products from, for example, Tsurumi Chemical Industry Co., Ltd., Karuizawa Sulfur Co., Ltd., Shikoku Chemical Industry Co., Ltd., Flexis Corporation, Nippon Kanzatsu Kogyo Co., Ltd., Hosoi Chemical Industry Co., Ltd., etc. can be used.

Crosslinking agents other than sulfur may be used. Specifically, for example, vulcanizing agents containing sulfur atoms such as TACKIROL V200 manufactured by Taoka Chemical Co., Ltd., DURALINK HTS (1,6-hexamethylene-sodium dithiosulfate dihydrate) manufactured by Flexis, and KA9188 (1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane: hybrid crosslinking agent) manufactured by LANXESS, and organic peroxides such as dicumyl peroxide can be used.

Each rubber composition preferably contains a vulcanization accelerator. The content of the vulcanization accelerator is, for example, more than 0.3 parts by mass and less than 10.0 parts by mass per 100 parts by mass of the rubber component.

Examples of vulcanization accelerators include thiazole-based vulcanization accelerators such as 2-mercaptobenzothiazole, di-2-benzothiazolyl disulfide, and N-cyclohexyl-2-benzothiazyl sulfenamide; thiuram-based vulcanization accelerators such as tetramethylthiuram disulfide (TMTD), tetrabenzylthiuram disulfide (TBzTD), and tetrakis(2-ethylhexyl)thiuram disulfide (TOT-N); sulfenamide-based vulcanization accelerators such as N-cyclohexyl-2-benzothiazole sulfenamide, N-t-butyl-2-benzothiazolyl sulfenamide, N-oxyethylene-2-benzothiazole sulfenamide, N-oxyethylene-2-benzothiazole sulfenamide, and N,N'-diisopropyl-2-benzothiazole sulfenamide; and guanidine-based vulcanization accelerators such as diphenyl guanidine, di-orthotolyl guanidine, and orthotolyl biguanidine. These may be used alone or in combination of two or more.

(i) Others In addition to the above-mentioned components, each rubber composition may contain additives generally used in the tire industry, such as organic fillers such as cellulose fibers, organic peroxides, etc. The content of these additives is, for example, more than 0.1 parts by mass and less than 50 parts by mass per 100 parts by mass of the rubber component.

In addition, the loss tangent (tan δ) of each rubber composition can be adjusted by adjusting the amount of carbon black and sulfur, making it possible to achieve the desired loss tangent (tan δ) without the need for excessive trial and error.

The complex modulus (E ^* ) can be adjusted by adjusting the amount of the curable resin component. The complex modulus (E ^* ) can also be adjusted by adjusting the amount of carbon black or sulfur. Specifically, the complex modulus (E ^* ) can be increased by increasing the amount of carbon black or sulfur. However, increasing the amount of carbon black increases the heat generation, and increasing the amount of sulfur decreases the heat generation. Therefore, it is preferable to first determine whether or not to use the curable resin component and the amount of the curable resin component, then adjust the amount of sulfur, and finally adjust the amount of carbon black, thereby achieving the desired complex modulus (E ^* ) without excessive trial and error.

(2) Preparation of Each Rubber Composition Each rubber composition can be prepared by a general method, for example, a production method including a base kneading step of kneading a rubber component with a filler such as carbon black, and a finish kneading step of kneading the kneaded product obtained in the base kneading step with a crosslinking agent.

The kneading can be carried out using a known (closed) kneading machine such as a Banbury mixer, kneader, or open roll.

The kneading temperature in the base kneading step is, for example, more than 50°C and less than 200°C, and the kneading time is, for example, more than 30 seconds and less than 30 minutes. In the base kneading step, in addition to the above components, compounding agents conventionally used in the rubber industry, such as softeners such as oil, stearic acid, zinc oxide, antioxidants, wax, vulcanization accelerators, etc., may be added and kneaded as necessary.

In the final kneading process, the mixture obtained in the base kneading process is kneaded with a crosslinking agent. The kneading temperature in the final kneading process is, for example, above room temperature and below 80°C, and the kneading time is, for example, more than 1 minute and less than 15 minutes. In the final kneading process, in addition to the above components, vulcanization accelerators, zinc oxide, etc. may be appropriately added and kneaded as necessary.

Each rubber composition obtained as above can then be extruded into a desired shape to be molded into a clinch, bead apex, or tread, respectively.

3. Tire Manufacturing The tire according to the present embodiment can be manufactured by a normal method, except for embedding electronic components during the molding process. First, the rubber compositions obtained above are molded into a predetermined shape to manufacture clinches, bead apexes, and treads. Next, they are combined with other rubber components on a tire building machine to manufacture an unvulcanized tire.

Specifically, an inner liner as a member for ensuring the airtightness of the tire, a carcass as a member for enduring the load, impact, and filling air pressure received by the tire, and a belt member as a member for tightening the carcass and increasing the rigidity of the tread are wound around a forming drum, both ends of the carcass are fixed to both side edges, and beads as members for fixing the tire to the rim are placed. After forming into a toroidal shape, the tread is attached to the center of the outer circumference, and sidewalls are attached to the radially outer side to form the side portions, thereby producing an unvulcanized tire. During this unvulcanized tire production process, electronic components are embedded in predetermined positions.

The unvulcanized tire obtained above is then heated and pressurized in a vulcanizer to obtain a tire. The vulcanization process can be carried out by applying known vulcanization methods. The vulcanization temperature is, for example, greater than 120°C and less than 200°C, and the vulcanization time is, for example, greater than 5 minutes and less than 15 minutes.

As mentioned above, the tire obtained by the above has electronic components between the carcass layer, which is thought to have a small amount of deformation around the electronic components during running, and the clinch, and the product of the loss tangent 70°C tan δCA of the clinch and the longitudinal length L (mm) of the electronic components is controlled to a certain value or less to appropriately suppress deformation of the clinch, thereby sufficiently preventing the occurrence of peeling of the electronic components and improving the durability of the electronic components attached to the tire during running.

The tire according to the present invention can be suitably used as a passenger car tire, a large passenger car tire, a large SUV tire, a truck/bus tire, a motorcycle tire, a racing tire, a studless tire (winter tire), an all-season tire, a run-flat tire, etc., and is particularly preferably used as a passenger car tire.

Below, we will show examples (embodiments) that are considered to be preferable for implementation, but the scope of the present invention is not limited to these examples.

We studied tires (tire sizes 195/65R15 (Study 1), 155/60R16 (Study 2), 215/50R17 (Study 3)) made of clinch rubber compositions, bead apex rubber compositions, tread rubber compositions, and other rubber components molded from the clinch rubber compositions, bead apex rubber compositions, and tread rubber compositions based on the various compounding materials shown below and Tables 1 to 3, and the results are shown in Tables 4 to 9.

1. Preparation of Each Rubber Composition Using various compounding materials shown below, a rubber composition for clinch, a rubber composition for tread, and a rubber composition for bead apex are prepared.

(1) Compounding Materials (a) Rubber Component (a) NR: TSR20
(ii) SBR-1: Modified S-SBR obtained by the method shown in the next paragraph
(Styrene content: 40% by mass, vinyl content: 25% by mass, 25% oil extended product)
(C) SBR-2: SLR6430 (S-SBR) manufactured by Trinseo
(Styrene content: 40% by mass, vinyl content: 24% by mass, 37.5% oil extended product)
(d) SBR-3: SBR1502 manufactured by ENEOS Materials Corporation
(styrene content: 23.5% by mass, vinyl content: 16% by mass, not oil extended)
(E) BR: UBEPOL BR150B (high sis BR) manufactured by Ube Industries
(Mw: 440,000, cis-1,4 bond content: 96% by mass)

(Production of SBR-1)
The SBR-1 is prepared according to the following procedure. First, two autoclaves with an internal volume of 10 L, an inlet at the bottom and an outlet at the top, and equipped with a stirrer and a jacket are connected in series as reactors, and butadiene, styrene, and cyclohexane are mixed in a predetermined ratio. This mixed solution is passed through a dehydration column filled with activated alumina, and mixed with n-butyllithium in a static mixer to remove impurities, and then continuously fed from the bottom of the first reactor, and further 2,2-bis(2-oxolanyl)propane as a polar substance and n-butyllithium as a polymerization initiator are continuously fed from the bottom of the first reactor at a predetermined rate, respectively, and the temperature inside the reactor is maintained at 95° C. The polymer solution is continuously withdrawn from the head of the reactor and fed to the second reactor. The temperature of the second reactor is kept at 95°C, and a mixture of tetraglycidyl-1,3-bisaminomethylcyclohexane (monomer) as a modifier and an oligomer component is continuously added as a 1000-fold diluted solution of cyclohexane at a predetermined speed to carry out a modification reaction. This polymer solution is continuously withdrawn from the reactor, and an antioxidant is continuously added using a static mixer. Further, 25 parts by mass of ENEOS Corporation extender oil NC140 per 100 parts by mass of the polymer is added to this polymer solution and mixed, and the solvent is then removed to obtain the desired oil-extended modified diene polymer (SBR-1).

The vinyl content (unit: mass%) of the SBR-1 obtained above was determined by infrared spectroscopy from the absorption intensity at about 910 cm ⁻¹ , which is the absorption peak of the vinyl group, and the styrene content (unit: mass%) was determined from the refractive index in accordance with JIS K6383 (1995).

(b) Compounding materials other than rubber components (a) Carbon black-1: Diablack N220 manufactured by Mitsubishi Chemical Corporation
(Average particle size: 23 nm, N ₂ SA: 114 m ² /g)
(b) Carbon black-2: Diablack N330 manufactured by Mitsubishi Chemical Corporation
(Average particle size: 31 nm, N ₂ SA: 79 m ² /g)
(c) Silica: Ultrasil VN3 manufactured by Eponic Industries
(N ₂ SA: 175 m ² /g, average primary particle diameter: 17 nm)
(d) Silane coupling agent: Si266 manufactured by Eponic Industries
(Bis(3-triethoxysilylpropyl)disulfide)
(E) Oil: H&R VivaTec 500 (TDAE oil)
(F) Thermosetting resin: PR12686 manufactured by Sumitomo Bakelite Co., Ltd.
(Cashew oil modified phenolic resin)
(G) Resin-1: Petrotac 100V manufactured by Tosoh Corporation
(C5C9 petroleum resin, softening point 96℃)
(H) Resin-2: SYLVATRAXX 4401 manufactured by Kraton
(α-methylstyrene (AMS) resin)
(i) Stearic acid: NOF Corp. bead stearic acid "Tsubaki"
(J) Wax: OZOACE-0355 manufactured by Nippon Seiro Co., Ltd.
(K) Anti-aging agent-1: Nocrac 6C manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(N-(1,3 dimethylbutyl)-N'-phenyl-p-phenylenediamine)
(L) Anti-aging agent-2: Nocrac RD manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(Poly(2,2,4-trimethyl-1,2-dihydroquinoline))
(W) Zinc oxide: Zinc oxide type 2 manufactured by Mitsui Mining & Smelting Co., Ltd. (K) Sulfur-1: Unnecessary sulfur manufactured by Sanshin Chemical Industry Co., Ltd. (20% oil content)
(Y) Sulfur-2: Powdered sulfur manufactured by Karuizawa Sulfur Co., Ltd. (T) Accelerator-1: Noccela NS manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(N-tert-butyl-2-benzothiazolylsulfenamide: TBBS)
(R) Accelerator-2: Noccela CZ manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(N-cyclohexyl-2-benzothiazolyl sulfenamide: CBS)
(S) Accelerator-3: Noccela D manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(1,3-diphenylguanidine: DPG)
(T) Accelerator-4: Noccela H manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(Hexamethylenetetramine: HMT)

(2) Rubber Composition for Clinch According to the composition shown in Table 1, materials other than sulfur and vulcanization accelerator are kneaded for 5 minutes under the condition of 150°C using a Banbury mixer to obtain a kneaded material. The amounts of each compound are in parts by mass.

Next, sulfur and a vulcanization accelerator are added to the kneaded mixture, which is then kneaded for 5 minutes at 80°C using an open roll to obtain rubber compositions for clinching CA-1 to CA-6.

(3) Preparation of rubber composition for bead apex In parallel, based on each formulation shown in Table 2, rubber compositions for bead apex tread BA-1 to BA-6 are obtained in the same manner as the preparation of the rubber composition for clinch.

(4) Preparation of Rubber Composition for Tread In parallel, rubber compositions for tread TR-1 to TR-4 are obtained in the same manner as the preparation of the rubber composition for clinching based on each formulation shown in Table 3.

2. Forming of Clinch, Bead Apex, and Tread Next, each of the rubber compositions obtained above is formed into a clinch, bead apex, and tread of a predetermined shape.

Of the physical properties listed in Tables 1 to 3, 70°C tan δ, 30°C tan δ, and 0°C tan δ were measured using a GABO Iplexer (registered trademark) at temperatures of 70°C, 30°C, and 0°C, respectively, using test pieces cut from each tire to have a length of 20 mm, width of 4 mm, and thickness of 1 mm, under conditions of a frequency of 10 Hz, initial strain of 5%, dynamic strain rate of 1%, and deformation mode: tension.

In addition, 70°C E ^* is measured using a test piece prepared in the same manner under conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain rate of 1%, and a deformation mode of tension using an "IPLEXER (registered trademark)" manufactured by GABO Corporation.

When preparing the test specimen, the length direction and circumferential direction of the test specimen shall be aligned. Furthermore, in the case of the tread, the thickness direction of the test specimen shall be aligned with the radial direction of the tire. If the thickness of each component is less than 1 mm, a test specimen of a certain thickness shall be taken from the thickest location on the tire equatorial plane of that component. For example, when measuring an inner liner with a thickness of 2 mm on the tire equatorial plane, a test specimen with a length of 20 mm x width of 4 mm x thickness of 1 mm shall be used, and when measuring an inner liner with a thickness of 0.5 mm on the tire equatorial plane, a test specimen with a length of 20 mm x width of 4 mm x thickness of 0.5 mm shall be used.

3. Tire Manufacturing Next, the clinch, bead apex, and tread obtained above are laminated together with other tire components in the combinations shown in Tables 4 to 9 to form unvulcanized tires, which are then press-vulcanized at 170° C. for 10 minutes to manufacture each test tire shown in Tables 4 to 9.

When forming an unvulcanized tire, an electronic component (RFID) of the size (weight W (g) and longitudinal length L (mm)) shown in Tables 4 to 9 is embedded in the embedding position shown in Tables 4 to 9. At this time, a plating layer containing copper and nickel is formed in advance on the surface of the electronic component, and a rubber coating layer having a thickness of 0.5 mm is provided. In Tables 4 to 9, embedding position 1 indicates that the electronic component is embedded between the carcass layer and the clinch (see Figure 1), and embedding position 2 indicates that the electronic component is embedded between the carcass layer and the sidewall portion (see Figure 3).

4. Calculation of parameters Next, for each test tire (an individual tire different from the tire from which the above test specimens were taken), the tire weight (kg), section height H (mm), and outer diameter Dt (mm) are measured, and the maximum load capacity (kg) is calculated based on these. In addition, D1, D2, and D3 are measured.

Then, 70°C tan δCA x L, tire weight/maximum load capacity, 70°C tan δBA x L, (70°C tan δBA + 70°C tan δCA) x L, (70°C E ^* BA + 70°C E ^* CA)/L, D1 x W, D2/D3, 70°C tan δBA x D1, (70°C tan δBA + 70°C tan δCA) x D1, and (70°C E ^* BA + 70°C E ^* CA)/D1 are calculated.

5. Performance evaluation test (evaluation of durability of electronic components while the tire is running)
(1) Test method Each test tire is fitted to all wheels of a vehicle (domestic FF vehicle, 2000cc displacement), and the vehicle is filled with air to an internal pressure of 230kPa. The vehicle is then driven on a test course in an overloaded state. Before the drive, the driver performs a reading test of the electronic components to check the reading performance. The test involves repeatedly driving over protrusions on the road surface and then normal driving, gradually increasing the speed from 50km/h, and recording the speed at which the driver feels something is wrong with the reading performance.

(2) Evaluation method Next, the results of Comparative Example 1 (Comparative Example 1-1, Comparative Example 2-1, Comparative Example 3-1) for each experiment were set as 100, and indexed based on the following formula to evaluate the durability of the tire while it was running. A larger value indicates better durability of the electronic components while the tire was running.
Durability of electronic components during tire operation
= [(Test tire results)/(Comparative example 1 results)] x 100

The present invention has been described above based on an embodiment, but the present invention is not limited to the above embodiment. Various modifications can be made to the above embodiment within the same or equivalent scope as the present invention.

The present invention (1) is
A tire having a tread portion, a carcass layer, a bead portion composed of a bead apex and a bead core, and a clinch,
An electronic component is provided between the carcass layer and the clinch,
The loss tangent 70°C tanδCA of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire is characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 1).
70℃tanδCA×L≦12 (Formula 1)

The present invention (2) is
The tire according to the present invention (1) is characterized in that the loss tangent 30°C tan δTR of the tread portion measured under conditions of a temperature of 30°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 0.25 or less.

The present invention (3) is
The tire according to the present invention (2) is characterized in that the loss tangent 30°C tan δTR of the tread portion measured under conditions of a temperature of 30°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 0.15 or less.

The present invention (4) is
The tire according to the present invention (2) or (3) is characterized in that the loss tangent 0°C tan δTR of the tread portion measured under conditions of a temperature of 0°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 0.50 or more.

The present invention (5) is
Tire weight (kg),
The tire is characterized in that the maximum load capacity (kg) of the tire satisfies the following (Formula 2), and is an arbitrary combination with any of the present inventions (1) to (4).
Tire weight/maximum load capacity<0.0150 (Equation 2)

The present invention (6) is
Tire weight (kg),
The tire is characterized in that the maximum load capacity (kg) of the tire satisfies the following (Equation 3), and is a tire described in the present invention (5).
Tire weight/maximum load capacity<0.0135 (Equation 3)

The present invention (7) is
The complex elastic modulus 70°C E ^* CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 6 MPa or more,
a loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire is characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 4), and is an arbitrary combination with any of the present inventions (1) to (6).
70°C tan δBA×L≦15 (Formula 4)

The present invention (8) is
a loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The loss tangent 70 ° C. tan δ CA of the clinch;
The tire is characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 5), and is an arbitrary combination with any of the present inventions (1) to (7).
(70℃tanδBA+70℃tanδCA)×L<30 (Formula 5)

The present invention (9) is
The complex elastic modulus 70°C E ^* BA (MPa) of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The complex elastic modulus 70°C E ^* CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire is characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 6), and is an arbitrary combination with any of the present inventions (1) to (8).
(70℃E ^* BA+70℃E ^* CA)/L>0.25 (Formula 6)

The present invention (10) is
The tire is characterized in that the electronic component is an RFID tag or a sensor, and is any combination with any of the present inventions (1) to (9).

The present invention (11) is
The tire is characterized in that an adhesive layer or a plating layer for improving adhesion to rubber is provided on the surface of the electronic component, and is an optional combination with any of the present inventions (1) to (10).

The present invention (12) is
The tire is characterized in that an electronic component covering layer having a thickness of 0.5 mm or more for covering the electronic components is provided, and is an optional combination with any of the present inventions (1) to (11).

The present invention (13) is
The tire is characterized in that the longitudinal length L (mm) of the electronic component is 80 mm or less, and is an optional combination with any of the present inventions (1) to (12).

The present invention (14) is
The tire is characterized in that the longitudinal length L (mm) of the electronic component is 50 mm or less, and is an optional combination with any of the present inventions (1) to (13).

The present invention (15) is
The weight W (g) of the electronic component;
The tire is characterized in that the shortest distance D1 (mm) from the electronic component to the outer surface of the tire satisfies the following (Formula 7), and is an arbitrary combination with any of the present inventions (1) to (14).
D1×W≦2.5 (Formula 7)

The present invention (16) is
The tire is characterized in that, in the tire radial direction, a distance D2 (mm) from the center position of the electronic component to the lower end of the bead core and a distance D3 (mm) from the maximum tire width position to the lower end of the bead core satisfy the following (Formula 8), and is any combination with any of the present inventions (1) to (15).
0.3≦D2/D3≦1.7 (Formula 8)

The present invention (17) is
a loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire is characterized in that the shortest distance D1 (mm) from the electronic component to the outer surface of the tire satisfies the following (Formula 9), and is an arbitrary combination with any of the present inventions (1) to (16).
70°C tan δBA x D1≦1.5 (Formula 9)

The present invention (18) is
a loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The loss tangent 70 ° C. tan δ CA of the clinch;
The tire is characterized in that the shortest distance D1 (mm) from the electronic component to the outer surface of the tire satisfies the following (Formula 10), and is an arbitrary combination with any of the present inventions (1) to (17).
(70℃tanδBA+70℃tanδCA)×D1≦2.5 (Formula 10)

The present invention (19) is
The complex elastic modulus 70°C E ^* BA (MPa) of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The complex elastic modulus 70°C E ^* CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire is characterized in that the shortest distance D1 (mm) from the electronic component to the outer surface of the tire satisfies the following (Formula 11), and is an arbitrary combination with any of the present inventions (1) to (18).
(70℃E ^* BA+70℃E ^* CA)/D1≧6.0 (Formula 11)

Reference Signs List 1 Tire 2 Bead portion 3 Sidewall portion 4 Tread portion 21 Bead core 22 Bead apex 23 Clinch 24 Chafer 31 Sidewall 32 Carcass layer 33 Inner liner 34 Electronic component 34a Body 34b Antenna L Length of electronic component in longitudinal direction

Claims (19)

A tire having a tread portion, a carcass layer, a bead portion composed of a bead apex and a bead core, and a clinch,
An electronic component is provided between the carcass layer and the clinch,
The loss tangent 70°C tanδCA of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
A tire characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 1).
70℃tanδCA×L≦12 (Formula 1) The tire according to claim 1, characterized in that the loss tangent 30°C tan δTR of the tread portion measured under the conditions of a temperature of 30°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 0.25 or less. The tire according to claim 2, characterized in that the loss tangent 30°C tan δTR of the tread portion measured under the conditions of a temperature of 30°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 0.15 or less. The tire according to claim 2 or 3, characterized in that the loss tangent 0°C tanδTR of the tread portion measured under the conditions of a temperature of 0°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 0.50 or more. Tire weight (kg),
5. The tire according to claim 1, wherein a maximum load capacity (kg) of the tire satisfies the following formula 2:
Tire weight/maximum load capacity<0.0150 (Equation 2) Tire weight (kg),
The tire according to claim 5, characterized in that the maximum load capacity (kg) of the tire satisfies the following (Equation 3).
Tire weight/maximum load capacity<0.0135 (Equation 3) The complex elastic modulus 70°C E ^* CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension, is 6 MPa or more,
A loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire according to any one of claims 1 to 6, characterized in that the length L (mm) of the electronic component in the longitudinal direction satisfies the following (Equation 4).
70°C tan δBA×L≦15 (Formula 4) A loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The loss tangent 70 ° C. tan δ CA of the clinch;
The tire according to any one of claims 1 to 7, characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Equation 5):
(70℃tanδBA+70℃tanδCA)×L<30 (Formula 5) The complex elastic modulus 70°C E ^* BA (MPa) of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The complex elastic modulus 70°C E ^* CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire according to any one of claims 1 to 8, characterized in that the longitudinal length L (mm) of the electronic component satisfies the following (Formula 6):
(70℃E ^* BA+70℃E ^* CA)/L>0.25 (Formula 6) The tire according to any one of claims 1 to 9, characterized in that the electronic component is an RFID tag or a sensor. The tire according to any one of claims 1 to 10, characterized in that an adhesive layer or a plating layer is provided on the surface of the electronic component to improve adhesion to the rubber. The tire according to any one of claims 1 to 11, characterized in that an electronic component covering layer having a thickness of 0.5 mm or more is provided to cover the electronic components. The tire according to any one of claims 1 to 12, characterized in that the longitudinal length L (mm) of the electronic component is 80 mm or less. The tire according to any one of claims 1 to 13, characterized in that the longitudinal length L (mm) of the electronic component is 50 mm or less. The weight W (g) of the electronic component;
The tire according to any one of claims 1 to 14, characterized in that a shortest distance D1 (mm) from the electronic component to an outer surface of the tire satisfies the following (Equation 7).
D1×W≦2.5 (Formula 7) 16. The tire according to claim 1, wherein a distance D2 (mm) from a center position of the electronic component to a lower end of the bead core in the tire radial direction, and a distance D3 (mm) from a maximum width position of the tire to the lower end of the bead core satisfy the following formula 8:
0.3≦D2/D3≦1.7 (Formula 8) a loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire according to any one of claims 1 to 16, characterized in that a shortest distance D1 (mm) from the electronic component to an outer surface of the tire satisfies the following (Equation 9):
70°C tan δBA×D1≦1.5 (Formula 9) A loss tangent 70°C tan δBA of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The loss tangent 70 ° C. tan δ CA of the clinch;
The tire according to any one of claims 1 to 17, characterized in that a shortest distance D1 (mm) from the electronic component to an outer surface of the tire satisfies the following (Formula 10):
(70℃tanδBA+70℃tanδCA)×D1≦2.5 (Formula 10) The complex elastic modulus 70°C E ^* BA (MPa) of the bead apex measured under the conditions of a temperature of 70°C, a frequency of 10 Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The complex elastic modulus 70°C E ^* CA (MPa) of the clinch measured under the conditions of a temperature of 70°C, a frequency of 10Hz, an initial strain of 5%, and a dynamic strain rate of 1%, in a deformation mode of tension;
The tire according to any one of claims 1 to 18, characterized in that the shortest distance D1 (mm) from the electronic component to an outer surface of the tire satisfies the following (Formula 11).
(70℃E ^* BA+70℃E ^* CA)/D1≧6.0 (Formula 11)

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