JP2024115419A - tire - Google Patents

Abstract

To improve durability of a tire mounted with an electronic component during running.SOLUTION: In a tire, an electronic component is arranged between a carcass layer and an inner liner layer, in a tire axial direction. A length LR (mm) in a longitudinal direction of the electronic component, loss tangent 70°CtanδSW of a side wall part measured under the condition that a temperature is 70°C, a frequency is 10 Hz, initial strain is 5% and dynamic strain is 1%, in a deformation mode of tension, a breaking elongation S (%) of a cord constituting the carcass layer, a thickness D1 (mm) of the inner liner layer, and an air permeation coefficient A1 (×10-11 cm3.cm/(cm2.s.cmHg)) of the inner liner layer measured by a differential-pressure method, in conformity with a method stipulated in JISK 6275-1:2009, under an environment of 40°C satisfy the following formula: LR×70°CtanδSW)/(S×(D1/A1))≤6.SELECTED DRAWING: Figure 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, because tires are made up of various rubber components, it is possible for air (including oxygen) to gradually pass through the rubber components. This raises concerns that oxygen passing through the rubber could cause deterioration of the metal parts of electronic components and reduce adhesion between the electronic components and the rubber around them.

Such deterioration of electronic components and reduced adhesion can lead to separation between the electronic components and rubber components due to shock loads during driving, which can reduce the durability of the tire.

Therefore, the objective of the present invention is to improve the durability of tires equipped with electronic components while they are in motion.

The present invention relates to
A tire having an inner liner layer, a carcass layer, a tread portion, and a sidewall portion,
An electronic component is provided between the carcass layer and the inner liner layer in the tire axial direction,
The longitudinal length LR (mm) of the electronic component;
The loss tangent 70°C tan δSW of the sidewall portion 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: tension;
The breaking elongation S (%) of the cord constituting the carcass layer;
A thickness D1 (mm) of the inner liner layer measured on a straight line L that provides the shortest distance from the center of the electronic component to the tire cavity surface in a tire radial cross section;
The tire is characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg) of the inner liner layer measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 under an environment of a temperature of 40°C satisfies the following (Formula 1):
(LR × 70 ° C. tan δSW) / (S × (D1 / A1)) ≦ 6 (Formula 1)

The present invention makes it possible to improve the durability of tires equipped with electronic components 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. 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 diagram illustrating 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. 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 an inner liner layer, a carcass layer, a tread portion, and a sidewall portion, and an electronic component is provided between the carcass layer and the inner liner layer in the tire axial direction. The longitudinal length LR (mm) of the electronic component, the loss tangent 70°C tan δSW of the sidewall portion measured in a deformation mode: 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%, the breaking elongation S (%) of the cord constituting the carcass layer, the thickness D1 (mm) of the inner liner layer measured on a straight line L that provides the shortest distance from the center of the electronic component to the tire cavity surface in the tire radial cross section, and the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg) of the inner liner layer measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 under an environment of a temperature of 40°C, satisfy the following (Formula 1).
(LR × 70 ° C. tan δSW) / (S × (D1 / A1)) ≦ 6 (Formula 1)

These features can improve the durability of tires equipped with electronic components while they are 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 mentioned above, tires are made up of various rubber components, and air (oxygen, etc.) can gradually pass through the rubber components. The oxygen that passes through the rubber can deteriorate the metal parts of the electronic components and reduce the adhesion of the electronic components to the rubber around them, which can reduce the durability of the tire.

Therefore, in the present invention, electronic components are provided between the carcass layer and the inner liner layer to reduce the effect of air (oxygen) from inside and outside the tire.

In other words, the carcass layer, which is located outside the electronic components, has other rubber components arranged on its outside and is sufficiently separated from the tire's outer surface, which is thought to reduce the effect of air (oxygen) outside the tire on the electronic components.

On the other hand, the inner liner layer, which is located inside the electronic components, is a material that prevents air from leaking from the tire cavity, and is inherently highly airtight (has a small air permeability coefficient) and therefore difficult for air to pass through.

However, even if the air permeability coefficient of the inner liner layer is small, if its thickness is insufficient, the passage of air cannot be sufficiently suppressed, and the durability of the tire cannot be sufficiently improved.

That is, in order to improve the durability of a tire, it is necessary to consider the air permeability coefficient and thickness of the inner liner layer, and as a specific means, the present inventors considered it necessary to appropriately control the ratio (D1/A1) of the thickness D1 (mm) of the inner liner layer to the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer.

When a tire is in motion, the tread portion comes into contact with the road surface (contact with the ground), causing the tire to deform. This deformation propagates through the sidewall portion and into the carcass layer and other parts. If the deformation around the electronic components becomes too great, this can cause separation between the electronic components and the rubber material, reducing the durability of the tire.

In other words, in order to improve tire durability, the relationship between the degree of tire deformation and the size of the electronic components must also be considered, and as a specific means, the inventors have considered it necessary to appropriately control the product (LR x 70°C tan δSW) of the longitudinal length LR (mm) of the electronic components and the loss tangent 70°C tan δSW of the sidewall portion measured in tension deformation mode 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%. Here, the loss tangent (tan δ) is a viscoelastic parameter that indicates the energy absorption performance, and since the larger the value, the more energy is absorbed and the more deformation occurs, it can also be considered a parameter of deformation.

As mentioned above, tire deformation propagates to the carcass layer and other layers, but the amount of deformation that occurs around the electronic components varies depending on the degree of breaking elongation of the cords (carcass cords) that make up the carcass layer. Therefore, in order to improve tire durability, it is necessary to take into account the breaking elongation of the cords (carcass cords).

Based on these ideas, various studies were carried out and it was concluded that if (LR x 70°C tan δSW)/(S x (D1/A1)) is 6 or less, it is believed that the durability of tires equipped with electronic components during driving can be sufficiently improved.

As described above, in the tire according to the present invention, the electronic components are provided between the carcass layer, which is sufficiently separated from the outer surface of the tire and can reduce the effect of air (oxygen) outside the tire on the electronic components, and the inner liner layer, which can sufficiently suppress the passage of air, and the relationship between (LR x 70°C tan δSW), S, and (D1/A1) is appropriately controlled, so that it is believed that the passage of air is sufficiently suppressed and the durability of the tire with the electronic components attached during driving can be improved.

In the above, the thickness D1 (mm) of the inner liner layer is the value measured on a straight line L that provides the shortest distance from the center of the electronic component to the tire cavity surface in the tire radial cross section.

The air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer is a value measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 in an environment of 40°C, and is preferably 20×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg) or less.

The loss tangent (tan δ) is a value measured using a viscoelasticity measuring device such as GABO's "IPLEXER (registered trademark)."

The breaking elongation S (%) of the carcass cord is a value measured in accordance with the method specified in JIS L1017:2002.

[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 the tread portion In the present invention, the loss tangent of the tread portion, 30°C tan δTR, measured in a deformation mode of tension 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%, is preferably 0.25 or less, and more preferably 0.15 or less. In this way, by setting the 30°C tan δTR to a small value, the rigidity of the tread portion can be sufficiently maintained during running to absorb energy, so that the occurrence of deformation can be reduced, the amount of deformation around the electronic components can be reduced, and the durability of the tire to which the electronic components are attached during running can be further improved.

As mentioned 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 and deformed. Therefore, by setting the 30°C tan δTR to a small value, it is possible to absorb energy while maintaining sufficient rigidity of the tread portion during driving. As a result, it is possible to reduce the occurrence of deformation and further reduce the amount of deformation around the electronic components, and it is believed that the durability of the tire with the electronic components attached during driving can be further improved.

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 tires equipped with electronic components 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, which is believed to sufficiently suppress the temperature rise of the entire tire and reduce the amount of deformation, thereby further improving the durability of tires equipped with electronic components 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 1/2 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". As with normal rims, 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 thickness of inner liner layer and loss tangent When a tire is in motion, each component generates heat due to deformation caused by rolling, etc., and the temperature rises. As the temperature rises, the air in the tire cavity expands, increasing the air pressure and making it easier for the air to penetrate into the tire.

In addition, as the temperature rises, the molecular motion of the inner liner layer becomes more active, reducing the steric hindrance that inhibits air permeation, making it easier for air to permeate into the tire.

The inventors of the present invention considered that in order to suppress such a temperature rise in the inner liner layer, it would be sufficient to make the thickness of the inner liner layer at a certain level or more relative to the loss tangent (tan δ), which is a viscoelastic parameter that indicates the energy absorption performance and is also a heat generation parameter. In other words, if the inner liner layer has a sufficient thickness, it is possible to suppress the temperature rise in the inner liner layer even if the loss tangent (tan δ) becomes somewhat large, and it is possible to suppress the penetration of air into the electronic components, thereby improving the durability of the tire to which the electronic components are attached during driving.

As a result of various investigations, it was found that if the ratio (D1/70°C tan δIL) of the thickness D1 (mm) of the inner liner layer to the loss tangent (70°C tan δIL) of the inner liner layer 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%, is 1.5 or more, the temperature rise of the inner liner layer can be suppressed and the penetration of air into the electronic components can be suppressed, thereby improving the durability of the tire to which the electronic components are attached during driving, which is considered to be more preferable.

4. Relationship between tire shape and air permeability coefficient of inner liner layer (1) In the tire shape, the ratio (D2/H) of the linear distance D2 (mm) in the tire radial direction from the upper end of the bead core to the center position of the electronic component to the tire cross-sectional height H (mm) can be considered as a parameter indicating the position of the electronic component, and the larger (D2/H) is, the more the electronic component is located on the radially outer side.

And because tires are subjected to centrifugal force when in motion, it is thought that the air molecules inside the tire also tend to be biased radially outward when in motion.

In other words, it is considered that the larger (D2/H) is, the more susceptible the inner liner is to the influence of the air inside the tire. For this reason, it is preferable to control the product ((D2/H)×A1) of the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer and (D2/H) to be smaller than a certain value, specifically, 10 or less.

In the above, "top end of the bead core" refers to the outer edge of the bead core in the tire radial direction, and "center position of the electronic component" refers to the position in the longitudinal center and widthwise center of the electronic component.

(2) Considering the effect of centrifugal force when the tire is running as described above, the sum (Rt+D2) of the tire rim diameter Rt (mm) and the linear distance D2 (mm) in the tire radial direction from the top end of the bead core to the center position of the electronic component can also be considered in the same way, instead of (D2/H), and it is preferable to control the product of (Rt+D2) and A1 ((Rt+D2)×A1) to be smaller than a certain value, specifically, 10,000 or less.

5. Relationship between tire shape and loss tangent (tan δ) of inner liner layer As described above, it can be considered that the larger (D2/H) is, the more electronic components are present on the radially outer side. At the same time, however, the amount of deformation of the tire during running increases, and the inner liner layer also generates a large amount of heat, making it easier for air to pass through.

For this reason, it is preferable to control the product of (D2/H) and 70°C tan δIL ((D2/H) x 70°C tan δIL) to be smaller than a certain value, specifically, 0.13 or less.

6. Tire Components Located on the Surface Side of the Carcass Layer In a tire, various tire components are arranged also on the outer side (surface side) of the carcass layer, and in order to suppress air intrusion from the tire surface, it is preferable to take into consideration the air permeability coefficient and thickness of these components.

Then, as a result of various studies, focusing on the tire component X (for example, a sidewall or a clinch) which is the thickest among the tire components located on the surface side (outside) of the carcass layer, it is considered that if the ratio (D3/A2) of the thickness D3 (mm) of the tire component X to the air permeability coefficient A2 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the tire component is 0.005 or more, intrusion of air from the tire surface can be suppressed, and the durability of the tire to which electronic components are attached during running can be further improved, which is more preferable.

In the above, D3 is a value measured on a straight line L that gives the shortest distance from the center of the electronic component to the tire cavity surface in the tire radial cross section.

7. Relationship between tire shape and electronic component position When (D2/H) is 0.5, the electronic components are located near the maximum tire width, and it is considered that the electronic components are less affected by centrifugal force, etc. in this area. Therefore, if the shortest distance D4 (mm) from the electronic components to the tire outer surface in this area is made relatively short, it is considered that air cooling during running can be achieved, and the impact of water vapor from the inside can be reduced.

On the other hand, as mentioned above, the larger (D2/H) is, the greater the deformation of the tire and the easier it is for heat to be generated in the inner liner layer. Therefore, as (D2/H) increases, it is believed that heat generation can be reduced by increasing D4 and reducing the deformation.

Conversely, the smaller (D2/H) is, the closer the electronic components will be to the rim. Because the rim easily transmits heat from braking while driving, it is necessary to prevent heat from being transmitted directly from the rim. To achieve this, it is considered preferable to increase D4 as the electronic components are closer to the rim (the smaller (D2/H) is).

In other words, it is preferable to increase D4 around the minimum value of (D2/H).

Based on these considerations, and as a result of various investigations, it was found that if (20×(D2/H−0.5) ² +2.0) is D4 or less, it is believed that the durability of a tire equipped with electronic components during running can be further improved, which is more preferable.

In the above, D4 is a value measured on a straight line L that gives the shortest distance from the center of the electronic component to the tire cavity surface in the tire radial cross section.

8. 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 read it 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 LR 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 (D4 x W) of the shortest distance D4 (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 D4 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 (D5/D6) of the distance D5 (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 D6 (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 "lower end of the bead core" refers to the lower edge of the bead core in the tire radial direction.

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

1. Tire according to the present embodiment Fig. 1 and Fig. 2 are each an example of a schematic cross-sectional view showing the configuration of a tire according to an embodiment of the present invention. In Fig. 1 and Fig. 2, 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 layer, and 34 is an electronic component. The carcass layer 32 is folded back from the inner side to the outer side in the tire width direction at the lower end of the bead core 21 along the bead core 21 and the bead apex 22 constituting 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 clinch 23 or the sidewall 31 corresponds to the above-mentioned "tire member X".

As shown in FIG. 1 and FIG. 2, in this embodiment, the electronic component 34 is provided between the carcass layer 32 and the inner liner layer 33. Here, "electronic components are provided between the carcass layer and the inner liner layer" means that the electronic components are provided between the surfaces opposite to the surfaces where the carcass layer and the inner liner layer are in contact with each other, and includes the case where the electronic components are embedded in the carcass layer or the inner liner layer. For example, in FIG. 1, the electronic components 34 are provided between the carcass layer 32 and the inner liner layer 33 above the bead portion 2 on the inner side in the tire width direction, and in FIG. 2, the electronic components 34 are provided between the carcass layer 32 and the inner liner layer 33 at the bead portion 2 on the inner side in the tire width direction.

Figure 3 is a schematic diagram explaining the form of the electronic component used in this embodiment, showing two examples (a) and (b). As shown in Figures 3(a) and (b), electronic component 34 is composed of main body 34a made of an IC chip and antenna 34b. In Figures 3(a) and (b), L is the longitudinal length of the electronic component.

With this configuration, the inner liner layer 33, the tread portion 4, the tire component X (clinch 23 or sidewall 31), and the carcass layer 32 satisfy the above-mentioned parameters, thereby improving the durability of the tire with electronic components attached during running.

2. Rubber Composition In the present embodiment, each of the rubber compositions constituting the above-mentioned inner liner layer, tread portion, and tire member X (hereinafter, each of them is referred to as the "rubber composition for inner liner", the "rubber composition for tread", and the "rubber composition for tire member X", 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 rubbers such as isoprene rubber, butadiene rubber (BR), styrene butadiene rubber (SBR), styrene isoprene butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and butyl rubber can be used. These may be used alone, or two or more may be used in combination. For example, in the rubber composition for tire member X, it is preferable to use isoprene rubber and BR in combination. And, in the rubber composition for tread, it is preferable to use SBR and BR in combination, and it is more preferable to use three types of rubber, SBR, BR, and isoprene rubber in combination. In addition, in the rubber composition for inner liner, it is preferable to use butyl rubber as the main rubber component and to use it in combination with isoprene rubber because it has excellent air barrier properties and heat resistance.

(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 tire member X, the content of isoprene-based rubber 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 80 parts by mass or less, and more preferably 50 parts by mass or less.

The rubber composition for the inner liner may contain 5 parts by mass or more and 50 parts by mass or less of isoprene-based rubber per 100 parts by mass of the rubber component, if necessary. The rubber composition for the tread may also contain 5 parts by mass or more and 95 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 the SBR is, for example, more than 100,000 and less than 2,000,000. The styrene content of the 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 the 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 the SBR (measurement of the styrene content and vinyl content) can be carried out, for example, using 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 s-(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. 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 treads, the content of SBR in 100 parts by mass of the rubber component is preferably 30 parts by mass or more, and more preferably 65 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 the rubber composition for tire member X, the content of SBR in 100 parts by mass of the rubber component is preferably 5 parts by mass or more, and more preferably 40 parts by mass or more. On the other hand, it is preferably 95 parts by mass or less, and more preferably 70 parts by mass or less.

The rubber composition for the inner liner may contain 1 part by mass or more and less than 15 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 (cis-1,4 content) 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 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 35 parts by mass or less.

In the rubber composition for tire member X, the content of BR in 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 95 parts by mass or less, and more preferably 60 parts by mass or less.

The rubber composition for the inner liner may contain 1 part by mass or more and less than 15 parts by mass of BR per 100 parts by mass of the rubber component, if necessary.

(d) Butyl Rubber As described above, in the rubber composition for the inner liner, it is preferable to use a butyl rubber as the main rubber component because butyl rubber has excellent air barrier properties and heat resistance.

As the butyl-based rubber, those normally used in the tire industry can be suitably used. Specifically, in addition to normal butyl rubber (IIR), examples include halogenated butyl rubber (X-IIR) such as brominated butyl rubber (Br-IIR), chlorinated butyl rubber (Cl-IIR), fluorinated butyl rubber (F-IIR), and brominated isobutylene-p-methylstyrene copolymer (Exxpro 3035 manufactured by Exxon Mobil Chemical). Among these, Br-IIR is preferably used because sulfur crosslinking is easily promoted even without containing natural rubber.

Recycled butyl rubber can also be used in combination with the butyl rubber. Recycled butyl rubber usually contains a high percentage of non-halogenated butyl rubber (regular butyl rubber), so by using it in combination with halogenated butyl rubber, good air barrier properties and vulcanization speed can be ensured. In particular, when a mixture of fatty acid metal salt and fatty acid amide is added to a formulation containing recycled butyl rubber, the performance balance between sheet processability and air barrier properties is remarkably improved in a synergistic manner, which is preferable.

Recycled butyl rubber is the butyl rubber content contained in crushed rubber products that contain a large amount of butyl rubber, such as tire tubes and bladders used in tire manufacturing, or in products obtained by heating and pressurizing the crushed products, and includes rubber components that have had their cross-linking bonds broken (desulfurization treatment) to make them re-vulcanizable. Generally, about 50% by mass of the crushed products is recycled butyl rubber. Note that recycled butyl rubber also contains sulfur, but it is deactivated to the extent that it does not participate in cross-linking.

Commercially available recycled butyl rubber products include tube recycled rubber manufactured by Muraoka Rubber Co., Ltd., which is produced by heat-treating butyl tubes under pressurized conditions, and bladder recycled rubber manufactured by Carquest Co., Ltd., which is obtained by crushing bladders in an extruder. These recycled butyl rubbers may be used alone or in combination of two or more types.

In the rubber composition for the inner liner, the content of butyl-based rubber in 100 parts by mass of the rubber component is preferably 50 parts by mass or more, and more preferably 80 parts by mass or more, because it has excellent air barrier properties. There is no particular upper limit and it may be 100 parts by mass, but from the viewpoint of sheet processability, it is preferably 95 parts by mass or less, and more preferably 90 parts by mass or less.

The content of recycled butyl rubber in 100 parts by mass of the rubber component is preferably 5 parts by mass or more, and more preferably 8 parts by mass or more, from the viewpoint of the benefits of using recycled butyl rubber. On the other hand, from the viewpoint of ensuring sufficient air barrier properties and vulcanization speed, the content is preferably 70 parts by mass or less, and more preferably 30 parts by mass or less.

The amount of recycled butyl rubber in 100 parts by mass of the total butyl rubber is preferably 7 parts by mass or more, and more preferably 10 parts by mass or more. On the other hand, it is preferably 75 parts by mass or less, and more preferably 35 parts by mass or less.

(e) 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 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 80 parts by mass or less, and more preferably 40 parts by mass or less.

In the rubber composition for tire member X, the content of carbon black 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 the inner liner, the content of carbon black per 100 parts by mass of the rubber component is, for example, preferably 40 parts by mass or more, and more preferably 45 parts by mass or more. On the other hand, it is preferably 85 parts by mass or less, and more preferably 80 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 10 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 120 parts by mass or less, and more preferably 80 parts by mass or less.

The rubber composition for tire component X and the rubber composition for the inner liner may contain 5 parts by mass or more and 40 parts by mass or less of silica per 100 parts by mass of the rubber component, as necessary, which allows sufficient extrusion processability and ozone resistance to 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 agents such as ethyl-N,N-dimethylthiocarbamoyl tetrasulfide and 3-triethoxysilylpropyl methacrylate monosulfide; mercapto-based agents such as 3-mercaptopropyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, and Momentive's NXT and NXT-Z; vinyl-based agents such as vinyltriethoxysilane and vinyltrimethoxysilane; amino-based agents such as 3-aminopropyltriethoxysilane and 3-aminopropyltrimethoxysilane; glycidoxy-based agents such as γ-glycidoxypropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane; nitro-based agents such as 3-nitropropyltrimethoxysilane and 3-nitropropyltriethoxysilane; and chloro-based agents such as 3-chloropropyltrimethoxysilane and 3-chloropropyltriethoxysilane. Among these, silane coupling agents having a thiocarbonyl group such as the above-mentioned NXT are preferred. 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 each rubber composition, the content of the plasticizer component per 100 parts by mass of the rubber component is preferably 2 parts by mass or more, and more preferably more than 3 parts by mass. On the other hand, it is preferably 80 parts by mass or less, and more preferably 20 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, synthetic oil, vegetable oil, animal oil, and mixtures thereof.

Examples of mineral oils include paraffinic, aromatic, and naphthenic oils, and examples of such products that can be used include those 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., and Fuji Kosan Co., Ltd. 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 the rubber composition contains acylglycerol 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 1H-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 terpenes classified as monoterpenes (C ₁₀ H ₁₆ ), sesquiterpenes (C ₁₅ H ₂₄ ), diterpenes (C ₂₀ H ₃₂ ), and 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.

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, pp. 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 (meth)acrylic components. The acrylic resin may have hydroxyl groups, carboxyl groups, silanol groups, 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) Processing Aid Each rubber composition may contain, as a processing aid, a mixture of a fatty acid metal salt and a fatty acid amide, if necessary.

The fatty acids constituting the fatty acid metal salt are not particularly limited, but can include saturated or unsaturated fatty acids preferably having 6 to 28 carbon atoms, more preferably having 10 to 25 carbon atoms, and even more preferably having 14 to 20 carbon atoms. Specific examples include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, arachidic acid, behenic acid, and nervonic acid. These can be used alone or in a mixture of two or more types. Among them, saturated fatty acids are preferred, and saturated fatty acids having 14 to 20 carbon atoms are more preferred.

Metals constituting fatty acid metal salts include alkali metals such as potassium and sodium, alkaline earth metals such as magnesium, calcium and barium, zinc, nickel, molybdenum, etc. Among these, zinc and calcium are preferred.

The fatty acid amide may be either saturated or unsaturated. Examples of saturated fatty acid amides include N-(1-oxooctadecyl)sarcosine, stearic acid amide, and behenic acid amide. On the other hand, examples of unsaturated fatty acid amides include oleic acid amide and erucic acid amide.

In each rubber composition, the content of the processing aid per 100 parts by mass of the rubber component is preferably 0.8 parts by mass or more, and more preferably 1.0 parts by mass or more. On the other hand, it is preferably 3.5 parts by mass or less, and more preferably 3.0 parts by mass or less.

(F) 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.

(G) 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.

(H) 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.

(i) 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 content of sulfur 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.

(J) 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.

(K) Carcass Cord Although it is not a compounding material of the rubber composition, the carcass cord will be described. For the carcass cord, a cord made of a material such as aramid, PET, nylon 6, nylon 6,6, rayon, etc. is used, and among them, a cord made of aramid or PET is preferably used. In this embodiment, the fineness of the carcass cord is preferably 500 dtex or more, and more preferably 1000 dtex or more. Also, it is preferably 10000 dtex or less, and more preferably 8000 dtex or less. The fineness of the carcass cord refers to the weight (g) per 1000 m of the carcass cord.

The thickness of the carcass cord is preferably 0.3 mm or more, and more preferably 0.5 mm or more. It is also preferable that the thickness is 1.2 mm or less, and more preferably 1 mm or less. The thickness of the carcass cord refers to the diameter of the circumscribed circle in a cross section perpendicular to the longitudinal direction of the carcass cord.

The number of twists in the carcass cord is preferably 20 or more, and more preferably 30 or more. It is also preferably 60 or less, and more preferably 40 or less. The number of twists in the carcass cord refers to the number of twists (turns/10 cm) per 10 cm in the longitudinal direction of the organic fiber cord inside the tire.

The number of ends of the carcass cord is preferably 10 or more, and more preferably 30 or more. It is also preferable that the number of ends is 100 or less, and more preferably 50 or less. The number of ends of the carcass cord refers to the number of ends per 50 mm in the arrangement direction in a cross section perpendicular to the longitudinal direction of the carcass cord.

In addition, in the rubber composition for the inner liner and the rubber composition for the tread, the loss tangent (tan δ) 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 breaking elongation S (%) of the carcass cord can be controlled to a desired value using known methods, such as by increasing the number of twists in the cord (i.e., increasing the twist angle of the cord) or by changing the thickness of the cord.

(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 mixture 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 of the resulting rubber compositions can then be extruded into a desired shape to form the inner liner, tread, and tire component X (clinch or sidewall), respectively.

The carcass can be obtained by topping (coating) the carcass cord with a carcass rubber composition, which is prepared separately using the above-mentioned compounding materials, and extruding it into a desired shape.

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 inner liner, tread, tire component X (clinch or sidewall), and carcass are manufactured as described above. Next, they are combined with other rubber components on a tire building machine to produce 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 thus produced 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 resulting tire has electronic components between the carcass layer, which is sufficiently separated from the tire outer surface to reduce the effect of air (oxygen) outside the tire on the electronic components, and the inner liner layer, which has (D1/A1) controlled to an appropriate value and can sufficiently suppress the passage of air, and therefore can sufficiently suppress the passage of air, improving the durability of the tire with the electronic components attached during driving.

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 the rubber composition for the inner liner, the rubber composition for the tread, and the rubber composition for tire component X based on the various compounding materials and Tables 1 to 3 shown below, the inner liner, the tread, and the tire component X (clinch or sidewall) molded from the rubber composition for tire component X, and the carcass made using the carcass cord shown in Table 4, and other rubber components, and the results of the study are shown in Tables 5 to 10.

1. Preparation of Each Rubber Composition Using various compounding materials shown below, a rubber composition for an inner liner, a rubber composition for a tread, and a rubber composition for a tire component X are prepared.

(1) Compounding Materials (a) Rubber Component (a) NR: TSR20
(b) SBR-1: Tufuden 3830 manufactured by Asahi Kasei Corporation
(styrene content: 36% by mass, vinyl content: 31% by mass, 37.5% oil extended)
(C) SBR-2: S-SBR produced by the following Production Example 1
(Styrene content: 25% by mass, vinyl content: 59% by mass, Tg: -22°C, weight average molecular weight: 250,000, non-oil extended)
(d) BR: UBEPOL BR150B (high sys BR) manufactured by Ube Industries, Ltd.
(Mw: 440,000, cis-1,4 content: 96% by mass)
(E) CL-IIR: CHLOROBUTYL 1066 manufactured by Japan Butyl Co., Ltd.
(Chlorinated butyl rubber, Cl: 1.26%)

(Production Example 1: Production of SBR-2)
Into a nitrogen-substituted autoclave reactor, 600 mL of hexane, 75 g of 1,3-butadiene, 25 g of styrene, and 60 mL of tetrahydrofuran are charged and stirred at 40°C. After scavenging by adding 0.5 mL of 0.1 mol/L n-butyllithium/hexane solution, 4 mL of 0.1 mol/L n-butyllithium/hexane solution is added and stirred at a stirring speed of 130 rpm and a jacket temperature of 80°C. After confirming the generation of a polymer with Mw of 250,000 by GPC, the polymerization solution is poured into 4 L of ethanol and the precipitate is collected. The obtained precipitate is dried by blowing air, and then dried under reduced pressure at 80°C/10 Pa or less until the loss on drying is 0.1%, to obtain SBR-2.

(b) Compounding materials other than rubber components (a) Carbon black-1: Showblack N220 manufactured by Cabot Japan Co., Ltd.
(Average particle size: 23 nm, N ₂ SA: 114 m ² /g)
(b) Carbon black-2: Showblack N351 manufactured by Cabot Japan Co., Ltd.
(C) Carbon black-3: Show Black N550 manufactured by Cabot Japan Co., Ltd.
(D) Carbon black-4: Showblack N660 manufactured by Cabot Japan Co., Ltd.
(e) Silica: Ultrasil VN3 manufactured by Eponic Industries
(N ₂ SA: 175 m ² /g, average primary particle diameter: 17 nm)
(F) Silane coupling agent: Si266 manufactured by Eponic Industries
(Bis(3-triethoxysilylpropyl)disulfide)
(G) Resin-1: PROMIX 400 manufactured by Flow Polymers
(Mixed resin of aliphatic and aromatic resins)
(H) Resin-2: SP-1068 manufactured by Schenectady International
(Alkylphenol-formaldehyde condensation resin)
(i) Resin-3: Sylvatraxx 4401 manufactured by Kraton
(α-Methylstyrene resin)
(J) Wax: OZOACE-0355 manufactured by Nippon Seiro Co., Ltd.
(Paraffin wax)
(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))
(Wa) Oil-1: Diana Process AH-24 (aroma oil) manufactured by Idemitsu Kosan Co., Ltd.
(K) Oil-2: Diana Process PS-32 (mineral oil) manufactured by Idemitsu Kosan Co., Ltd.
(Y) Processing aid: ULTRAFLOW 440 manufactured by Performance Adedibs
(Mixture of fatty acids and metal soaps)
(p) Stearic acid: NOF Corp.'s "Tsubaki" bead stearic acid
(R) Zinc oxide: Zinc oxide No. 1 manufactured by Mitsui Mining & Smelting Co., Ltd. (S) Sulfur: 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)
(N) Accelerator-2: Noccela DM-P manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
(Di-2-benzothiazolyl disulfide: DM)
(N) Accelerator-3: Socraseal DG manufactured by Sumitomo Chemical Co., Ltd.
(1,3-diphenylguanidine: DPG)

(2) Rubber composition for inner liner 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 inner liners IL-1 to IL-6.

(3) Preparation of rubber composition for tire component X In parallel, rubber compositions for tire component X, TM-1 to TM-4, are obtained in the same manner as the preparation of the rubber composition for the inner liner based on each formulation shown in Table 2. Note that TM-1 and TM-2 are formulations for preparing a sidewall as tire component X, and TM-3 and TM-4 are formulations for preparing a clinch as tire component X.

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

2. Molding of Inner Liner, Tire Component X, and Tread Next, the obtained rubber compositions are molded into inner liners, tire components X (sidewalls, clinches), and treads having predetermined shapes.

3. Preparation of Carcass From the above-mentioned blended materials, NR (75 parts by mass), SBR-1 (25 parts by mass), carbon black-2 (45 parts by mass), oil-1 (9 parts by mass), stearic acid (2.0 parts by mass), zinc oxide (3.0 parts by mass), sulfur (3.75 parts by mass), and accelerator-1 (1.0 parts by mass) are used to obtain a rubber composition for carcass in the same manner as the preparation of the rubber composition for innerliner. Then, the obtained rubber composition for carcass is topped on both sides of the cord (CA-1, CA-2) shown in Table 4 and molded into a predetermined shape to prepare two types of carcass.

4. Manufacturing of Tires Next, the inner liner, tire component X, tread, and carcass obtained above are laminated together with other tire components in the combinations shown in Tables 5 to 10 to form unvulcanized tires, which are press-vulcanized for 10 minutes under a condition of 170° C. to manufacture each test tire shown in Tables 5 to 10.

When forming an unvulcanized tire, an electronic component (RFID) with the size, weight W (g) and longitudinal length LR (mm) shown in Tables 5 to 10 is embedded in the embedding position shown in Tables 5 to 10. At this time, a plating layer containing copper and nickel is formed on the surface of the electronic component in advance, and a rubber coating layer with a thickness of 0.5 mm is provided. In Tables 5 to 10, embedding position 1 indicates embedding the electronic component between the sidewall portion and the carcass layer (see Figure 4), embedding position 2 indicates embedding the electronic component between the clinch portion and the bead apex (see Figure 5), embedding position 3 indicates embedding the electronic component between the inner liner and the carcass layer above the bead portion on the inner side in the tire width direction (see Figure 1), and embedding position 4 indicates embedding the electronic component between the inner liner and the carcass layer at the bead portion on the inner side in the tire width direction (see Figure 2).

Among the physical properties listed in Tables 1 to 3, 70°C tan δ, 30°C tan δ, and 0°C tan δ are measured by using a GABO "Iplexer (registered trademark)" to measure test pieces prepared by vulcanizing and molding each rubber composition under the same conditions as tire manufacturing, under conditions of a frequency of 10 Hz, initial strain of 5%, dynamic strain rate of 1%, deformation mode: tension, and temperatures of 70°C, 30°C, and 0°C, respectively. The length direction and circumferential direction of the test piece are to be aligned. Furthermore, the thickness direction of the test piece is to be aligned with the radial direction of the tire in the case of the tread and inner liner, and is to be parallel to the straight line L in the case of tire component X. In addition, when the thickness of each component is less than 1 mm, a test piece of a certain thickness is taken from the thickest place on the tire equatorial plane of that component. For example, when measuring an inner liner with a thickness of 2 mm on the tire's equatorial plane, a test piece with a length of 20 mm, width of 4 mm, and thickness of 1 mm is used; when measuring an inner liner with a thickness of 0.5 mm on the tire's equatorial plane, a test piece with a length of 20 mm, width of 4 mm, and thickness of 0.5 mm is used.

In addition, the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) is measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 in an environment of 40°C using a test piece cut out from a tire to have a length of 20 mm × width of 20 mm × thickness of 0.3 mm.

Among the physical properties listed in Table 4, the breaking elongation of the cord refers to the elongation rate of the sample cord measured when the cord breaks. The cord (sample cord) is removed from each test tire, and immediately after removal, the sample cord is set between a pair of gripping tools on an autograph so that the cord is straight and does not sag. The measurement is performed in accordance with the method specified in JIS L1017:2002, with a gripping distance of 250 mm and a pulling speed of 300 mm/min.

The fineness of the cord is calculated by extracting a length of 10 cm or more from the tire, removing the rubber coating around the extracted cord, calculating the weight per 1000 m, and averaging the values calculated for 10 cords. Furthermore, the thickness of the cord and the number of twists are calculated from the tire.

5. Calculation of parameters Next, for each test tire, 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, each of D1 to D6 is measured.

Then, calculate (LR x 70°C tan δ SW)/(S x (D1/A1)), D1/70°C tan δ IL, (D2/H) x A1, (Rt + D2) x A1, (D2/H) x 70°C tan δ IL, D3/A2, D4-{20 x (D2/H-0.5)2 + 2.0}, D4 x W, and D5/D6.

6. Performance evaluation test (evaluation of tire durability during driving)
(1) Test method Each test tire is fitted to all wheels of a vehicle (a domestic FF vehicle with an engine displacement of 2000 cc), and the vehicle is filled with air to an internal pressure of 230 kPa. The vehicle is then driven on a test course in an overloaded state. The test is performed by repeatedly driving over protrusions on the road surface and then running normally. The test starts with driving at a speed of 50 km/h, and the speed is gradually increased with each repetition, and the driving speed just before the driver feels something is wrong is recorded.

(2) Evaluation Method Next, the results of Comparative Example 1 (Comparative Example 1-1, Comparative Example 2-1, Comparative Example 3-1) for each study were set as 100, and indexed based on the following formula to evaluate the durability of the tire during running. A larger value indicates better durability of the tire during running.
Tire durability during driving
= [(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 an inner liner layer, a carcass layer, a tread portion, and a sidewall portion,
An electronic component is provided between the carcass layer and the inner liner layer in the tire axial direction,
The longitudinal length LR (mm) of the electronic component;
The loss tangent 70°C tan δSW of the sidewall portion 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: tension;
The breaking elongation S (%) of the cord constituting the carcass layer;
A thickness D1 (mm) of the inner liner layer measured on a straight line L that provides the shortest distance from the center of the electronic component to the tire cavity surface in a tire radial cross section;
The tire is characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg) of the inner liner layer measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 under an environment of a temperature of 40°C satisfies the following (Formula 1):
(LR × 70 ° C. tan δSW) / (S × (D1 / A1)) ≦ 6 (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 tire is characterized in that the air permeability coefficient A1 of the inner liner layer is 20×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg) or less, and is any combination with any of the present inventions (1) to (6).

The present invention (8) is
The D1 (mm),
The loss tangent 70°C tan δIL of the inner liner layer measured 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%, in a deformation mode of tension, satisfies the following (Formula 4), and is a tire in any combination with any of the present inventions (1) to (7).
D1/70°C tan δIL≧1.5 (Formula 4)

The present invention (9) is
A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
Tire section height H (mm),
The tire is characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer satisfies the following (Formula 5), and is an arbitrary combination with any of the present inventions (1) to (8).
(D2/H)×A1≦10 (Formula 5)

The present invention (10) is
The tire rim diameter Rt (mm),
A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
The tire is characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer satisfies the following (Formula 6), and is an arbitrary combination with any of the present inventions (1) to (9).
(Rt+D2)×A1≦10000 (Formula 6)

The present invention (11) is
A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
Tire section height H (mm),
The loss tangent 70°C tan δIL of the inner liner layer measured 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%, in a deformation mode of tension, satisfies the following (Formula 7), and is a tire in any combination with any of the present inventions (1) to (10).
(D2/H) x 70°C tan δIL≦0.13 (Formula 7)

The present invention (12) is
Among the tire components arranged on the tire surface side of the carcass layer, in the tire component having the largest thickness on the straight line L,
A thickness D3 (mm) of the tire member on the straight line L;
The tire is characterized in that the air permeability coefficient A2 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the tire member measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 under an environment of a temperature of 40° C. satisfies the following (Formula 8), and is an arbitrary combination with any of the present inventions (1) to (11).
D3/A2≧0.005 (Formula 8)

The present invention (13) is
The shortest distance D4 (mm) from the electronic component to the outer surface of the tire;
A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
The tire is characterized in that the tire cross-sectional height H (mm) satisfies the following (Formula 9), and is an arbitrary combination with any of the present invention (1) to (12).
D4≧20×(D2/H-0.5) ² +2.0 (Formula 9)

The present invention (14) is
The weight W (g) of the electronic component;
The tire is characterized in that the shortest distance D4 (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 (13).
D4×W≦2.5 (Formula 10)

The present invention (15) 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 (14).

The present invention (16) 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 (15).

The present invention (17) 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 (16).

The present invention (18) is
The tire is characterized in that the longitudinal length LR (mm) of the electronic component is 80 mm or less, and is an arbitrary combination with any of the present inventions (1) to (17).

The present invention (19) is
The tire according to the present invention (18), characterized in that the longitudinal length LR (mm) of the electronic component is 50 mm or less.

The present invention (20) is
The tire is characterized in that, in the tire radial direction, a distance D5 (mm) from the center position of the electronic component to the lower end of the bead core and a distance D6 (mm) from the maximum tire width position to the lower end of the bead core satisfy the following (Formula 11), and is an arbitrary combination with any of the present inventions (1) to (19).
0.3≦D5/D6≦1.7 (Formula 11)

The present invention (21) is
The tire is characterized in that the fineness of the cord constituting the carcass layer is 500 dtex or more and 10,000 dtex or less, and is an arbitrary combination with any of the present inventions (1) to (20).

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 layer 34 Electronic component 34a Body 34b Antenna

Claims (21)

A tire having an inner liner layer, a carcass layer, a tread portion, and a sidewall portion,
An electronic component is provided between the carcass layer and the inner liner layer in the tire axial direction,
The longitudinal length LR (mm) of the electronic component;
The loss tangent 70°C tan δSW of the sidewall portion 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: tension;
The breaking elongation S (%) of the cord constituting the carcass layer;
A thickness D1 (mm) of the inner liner layer measured on a straight line L that provides the shortest distance from the center of the electronic component to the tire cavity surface in a tire radial cross section;
A tire characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg) of the inner liner layer measured by a differential pressure method in accordance with the method specified in JIS K6275-1:2009 under an environment of a temperature of 40°C satisfies the following (Formula 1):
(LR × 70 ° C. tan δSW) / (S × (D1 / A1)) ≦ 6 (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 tire according to any one of claims 1 to 6, characterized in that the inner liner layer has an air permeability coefficient A1 of 20 x 10 ^-11 cm ³ ·cm/(cm ² ·s ·cmHg) or less. The D1 (mm),
The tire according to any one of claims 1 to 7, characterized in that the loss tangent 70°C tan δIL of the inner liner layer measured 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%, in a deformation mode of tension, satisfies the following (Equation 4).
D1/70°C tan δIL≧1.5 (Formula 4) A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
Tire section height H (mm),
The tire according to any one of claims 1 to 8, characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer satisfies the following (Equation 5).
(D2/H)×A1≦10 (Formula 5) The tire rim diameter Rt (mm),
A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
The tire according to any one of claims 1 to 9, characterized in that the air permeability coefficient A1 (×10 ⁻¹¹ cm ³ ·cm/(cm ² ·s ·cmHg)) of the inner liner layer satisfies the following (Formula 6).
(Rt+D2)×A1≦10000 (Formula 6) A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
Tire section height H (mm),
The tire according to any one of claims 1 to 10, characterized in that the loss tangent 70°C tan δIL of the inner liner layer measured 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%, in a deformation mode of tension, satisfies the following (Equation 7).
(D2/H) x 70°C tan δIL≦0.13 (Formula 7) Among the tire components arranged on the tire surface side of the carcass layer, in the tire component having the largest thickness on the straight line L,
A thickness D3 (mm) of the tire member on the straight line L;
The tire according to any one of claims 1 to 11, characterized in that an air permeability coefficient A2 (×10 ^-11 cm ³ ·cm/(cm ² ·s ·cmHg)) of the tire member measured by a differential pressure method in accordance with a method specified in JIS K6275-1:2009 under an environment of a temperature of 40°C satisfies the following (Formula 8):
D3/A2≧0.005 (Formula 8) The shortest distance D4 (mm) from the electronic component to the outer surface of the tire;
A linear distance D2 (mm) in the tire radial direction from an upper end of a bead core to a center position of the electronic component;
The tire according to any one of claims 1 to 12, characterized in that the tire cross section height H (mm) satisfies the following (Equation 9).
D4≧20×(D2/H-0.5) ² +2.0 (Formula 9) The weight W (g) of the electronic component;
The tire according to any one of claims 1 to 13, characterized in that a shortest distance D4 (mm) from the electronic component to an outer surface of the tire satisfies the following (Formula 10).
D4×W≦2.5 (Formula 10) The tire according to any one of claims 1 to 14, characterized in that the electronic component is an RFID tag or a sensor. The tire according to any one of claims 1 to 15, 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 16, 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 17, characterized in that the longitudinal length LR (mm) of the electronic component is 80 mm or less. The tire described in claim 18, characterized in that the longitudinal length LR (mm) of the electronic component is 50 mm or less. 20. The tire according to claim 1, wherein a distance D5 (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 D6 (mm) from a maximum width position of the tire to the lower end of the bead core satisfy the following (Formula 11):
0.3≦D5/D6≦1.7 (Formula 11) The tire according to any one of claims 1 to 20, characterized in that the cords constituting the carcass layer have a fineness of 500 dtex or more and 10,000 dtex or less.

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