Tire with Functional Parts

Abstract

To provide a tire which includes a storage body storing a functional component on a tire inner surface of a tread part, and is excellent in sensing strength of a sensor function possessed by the functional component and durability of the storage body.SOLUTION: A tire with a functional component includes a storage body storing a functional component on a tire inner surface of a tread part, wherein the functional component has at least a contact surface contacting the tire inner surface and a sensor function for detecting tire information, the storage body is composed of a rubber component, the rubber component contains 60 mass% or more of butyl rubber (IIR) and has a content ratio of natural rubber (NR) of 40 mass% or less, and 40 to 82 pts.mass of carbon black is contained with respect to 100 pts.mass of the rubber component.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a tire provided with a functional component having a sensor function for detecting tire information on the inner surface of the tire.

Background Art

[0002] In order to detect tire information, functional components having a sensor function (such as electronic components such as sensor units) are disposed on tires. In particular, due to ease of detecting air pressure and wear, such functional components are disposed on the inner surface of the tread portion of the tire (for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, the container that houses the functional component disposed on the inner surface of the tread portion of the tire is liable to be subjected to forces due to the rotation of the tire during running and impacts from the road surface, etc., and thus has problems in terms of durability. And, in Patent Document 1 and Patent Document 2, tires are disclosed in which peeling from the tire surface of an electronic component mounting member (container), etc. hardly occurs even when a large impact is applied during high-speed running or during high-speed running in a low-temperature environment, but these have room for improvement because the rubber physical properties of the members constituting the tire and the mounting positions of the electronic component mounting members (containers) are restricted. Further, this functional component is unlikely to have a high sensing intensity of the sensor function due to the influence of the rotation of the tire during running, etc., and there is also room for further improvement in this regard.

[0005] Therefore, an object of the present invention is to provide a tire having a container housing functional components on the inner surface of the tread portion of the tire, and excellent in the sensing intensity of the sensor function of the functional components and the durability of the container.

Means for Solving the Problems

[0006] In order to solve the above problems, the present inventor has intensively studied and provided a container housing functional components on the inner surface of the tread portion of the tire. The functional components have at least a contact surface in contact with the inner surface of the tire and a sensor function for detecting tire information. The container is composed of a rubber component, and the rubber component contains 60% by mass or more of butyl rubber (IIR) and the content ratio of natural rubber (NR) is 40% by mass or less. Further, a tire containing 40 to 82 parts by mass of carbon black with respect to 100 parts by mass of the rubber component has been found to have excellent sensing intensity of the sensor function of the functional components and excellent durability of the container, and the present invention has been completed.

[0007] That is, the present invention is as follows <1> to <8>. <1> A tire provided with a container housing functional components on the inner surface of the tread portion of the tire, The functional components have at least a contact surface in contact with the inner surface of the tire and a sensor function for detecting tire information, The container is composed of a rubber component, the rubber component contains 60% by mass or more of butyl rubber (IIR) and the content ratio of natural rubber (NR) is 40% by mass or less, and further contains 40 to 82 parts by mass of carbon black with respect to 100 parts by mass of the rubber component. <2> The tire according to <1>, wherein the container contains a total of 40 to 85 parts by mass of the carbon black and the white filler with respect to 100 parts by mass of the rubber component. <3> The tire according to <2>, wherein the white filler is at least one selected from the group consisting of silica, talc, mica, clay, and calcium carbonate. <4> The average value of the nitrogen adsorption specific surface area (N2SA) of the carbon black is 50 m 2The tire according to any one of <1> to <3>, which is below / g. <5>The tire according to any one of <1> to <4>, wherein the tensile stress (M100) at 100% elongation of the container at 100 ° C is 5.0 MPa or less. <6>The tire according to any one of <1> to <5>, wherein the container is fixed to the inner surface of the tire. <7>The tire according to <6>, wherein the container is fixed to the inner surface of the tire by an adhesive. <8>The tire according to any one of <1> to <7>, wherein the sensor function of the functional component is a sensor function using a piezoelectric element as a sensor element.

Advantages of the Invention

[0008] According to the present invention, it is possible to obtain a tire having a container in which a functional component is housed on the inner surface of the tire in the tread portion, and excellent sensing strength of the sensor function of the functional component and durability of the container.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0010] The present invention will be described. The present invention provides a tire having a container in which functional components are accommodated on the inner surface of the tread portion of the tire. The functional components have at least a contact surface that contacts the inner surface of the tire and a sensor function for detecting tire information. The container is made of a rubber component, the rubber component contains 60% by mass or more of butyl rubber (IIR) and the content ratio of natural rubber (NR) is 40% by mass or less, and further contains 40 to 82 parts by mass of carbon black with respect to 100 parts by mass of the rubber component. Hereinafter, this will also be referred to as "the tire of the present invention".

[0011] In the present invention, the numerical range represented by "~" means a numerical range in which the numerical value described before "~" is the lower limit value and the numerical value described after "~" is the upper limit value, unless otherwise specified.

[0012] Hereinafter, the configuration, contained components and their contents of the container provided in the tire of the present invention, the configuration of the tire of the present invention (as a whole), etc. will be described in detail with reference to the drawings. Note that the dimensional ratios (length, thickness, etc.) and orientations of each member shown in the drawings may be different from the actual dimensional ratios and orientations in order to facilitate the understanding of the invention. Also, some may omit reference signs, etc.

[0013] [Container] The container provided in the tire of the present invention is made of a predetermined rubber component. The container is provided on the inner surface of the tread portion of the tire and houses a functional component having a sensor function for detecting tire information so as to have a contact surface that contacts the inner surface of the tire. For example, as shown in FIGS. 1 to 3, the base portion 31 of the container 30 is joined and fixed to the inner surface 12 of the tread portion 1 of the tire (the inner surface 12 joined to the base portion 31 is omitted in FIGS. 2 and 3), and the housing portion 33 houses the functional component 20 so as to be surrounded by the side wall 32. Further, an embodiment is shown in which the housed functional component 20 has a contact surface 21 that contacts the inner surface 12 of the tread portion 1 via the base portion 31.

[0014] Here, the statement that the container is "provided on the inner surface of the tire tread portion" means that the container is connected and arranged on the inner surface of the tire tread portion (the inner peripheral surface of the tire located at a position facing the tread surface of the tread portion). Also, the statement that the functional component has a "contact surface that contacts the inner surface of the tire (of the tread portion)" includes not only the embodiment in which the functional component directly contacts the inner surface of the tire tread portion, but also the embodiment in which the functional component contacts through a member (the base portion 31 in the embodiment of FIG. 1) that is in surface contact with the inner surface of the tire tread portion in the container. That is, the embodiment in which the functional component is in direct surface contact with the inner surface of the tire tread portion and the embodiment in which the functional component is in surface contact through a member that is in surface contact with the inner surface of the tire tread portion in the container are included.

[0015] And it is more preferable that the container containing this functional component is fixed to the inner surface of the tire tread portion (in a state where the position of the container does not substantially change), and further, it is more preferable that this is an embodiment in which the container is fixed to the inner surface of the tire tread portion by an adhesive. As this adhesive, an epoxy-based adhesive, an acrylic-based adhesive, etc. can be used. Also, a double-sided tape or the like may be used as the adhesive.

[0016] Hereinafter, details of each component included in this container and physical properties of this container will be described.

[0017] <Rubber component> The container provided in the tire of the present invention is composed of a rubber component containing 60% by mass or more of butyl rubber (IIR) and having a natural rubber (NR) content of 40% by mass or less. That is, this container is composed of a rubber component, and this rubber component contains 60% by mass or more of butyl rubber (IIR) and the content ratio of natural rubber (NR) is 40% by mass or less. This rubber component is not particularly limited as long as it contains butyl rubber (IIR) at a content ratio of 60% by mass or more and the content ratio of natural rubber (NR) is 40% by mass or less, and any known rubber component used (used in combination) for applications constituting rubber products such as diene rubbers and so-called non-diene rubbers can be used. Examples of diene rubbers include, in addition to the above-mentioned natural rubber (NR), for example, butadiene rubber (BR), styrene-butadiene copolymer rubber (styrene-butadiene rubber, SBR), acrylonitrile-butadiene copolymer rubber (nitrile rubber, NBR), chloroprene rubber (CR), synthetic isoprene rubber (IR), styrene-isoprene copolymer rubber, isoprene-butadiene copolymer rubber, styrene-butadiene-vinylpyridine terpolymer (VP), and the like. Furthermore, in addition to the above-mentioned butyl rubber (IIR), it is also possible to use in combination rubber components other than diene rubbers such as olefin rubbers (ethylene-propylene rubber, acrylic rubber, etc.), fluororubbers, and silicone rubbers. Also, as the butyl rubber (IIR), recycled butyl rubber obtained by recycling from used rubber products and the like can be used.

[0018] In addition, the content ratio of butyl rubber (IIR) in the rubber component constituting the container provided in the tire of the present invention is more preferably more than 60% by mass, further preferably 65% by mass or more, further preferably 70% by mass or more, further preferably 80% by mass or more, and further preferably 90% by mass or more. The upper limit may be 100% by mass, but more preferably 95% by mass or less. In addition, the content ratio of butyl rubber (IIR) in the present invention is the content ratio of the entire butyl rubber including recycled butyl rubber when it is included (the same applies hereinafter). In addition, the content ratio of natural rubber (NR) in the rubber component constituting the container provided in the tire of the present invention is more preferably less than 40% by mass, even more preferably 35% by mass or less, even more preferably 30% by mass or less, may be 20% by mass or less, and may be 10% by mass or less, since the effects of the present invention are more likely to be exhibited. The lower limit may be 0% by mass (embodiment not substantially containing), but is more preferably 1% by mass or more, and even more preferably 5% by mass or more.

[0019] Furthermore, when the rubber component constituting this container contains both natural rubber (NR) and butyl rubber (IIR), since the effects of the present invention are more likely to be exhibited, the ratio of butyl rubber (IIR) to natural rubber (NR) in this rubber component is more preferably 1.5 times or more (IIR / NR is 1.5 or more), even more preferably 2 times or more (IIR / NR is 2.0 or more), even more preferably 2.5 times or more (IIR / NR is 2.5 or more), even more preferably 3 times or more (IIR / NR is 3.0 or more), and even more preferably 5 times or more (IIR / NR is 5.0 or more). The upper limit is not particularly limited, and may be, for example, 50 times or less (IIR / NR is 50 or less).

[0020] <Carbon black> The container provided in the tire of the present invention contains carbon black in addition to the above-described predetermined rubber component as a constituent component. This carbon black is not particularly limited, and any known carbon black used in applications such as rubber products can be used. Specific examples of carbon black include those of various grades such as SAF-HS, SAF, ISAF-HS, ISAF, ISAF-LS, IISAF-HS, HAF-HS, HAF, HAF-LS, FEF, GPF, SRF, FT, MT, etc. Also, recycled carbon black obtained by recycling from used rubber products or the like can be used. And this carbon black may be used alone or in combination of two or more. Incidentally, from the aspect of making it easier to further improve the durability of the container, etc., the average value of the nitrogen adsorption specific surface area (N2SA) of this carbon black is preferably 50 m 2 / g or less, more preferably 45 m 2 / g or less, and even more preferably 40 m 2 / g or less. That is, it is more suitable that the particle size of the carbon black is larger. The lower limit is preferably 10 m 2 / g or more, more preferably 15 m 2 / g or more, and even more preferably 23 m 2 / g or more.

[0021] Here, this "carbon black" means carbon fine particles composed of primary particles with a diameter of about 3 to 500 nm industrially manufactured with quality control. Further, the nitrogen adsorption specific surface area (N2SA) of the carbon black is a value measured in accordance with JIS K6217-2:2017. Furthermore, the "average value of the nitrogen adsorption specific surface area (N2SA) of carbon black" is the value of the nitrogen adsorption specific surface area (N2SA) of that carbon black when using one type alone, and when using two or more types in combination, it is the value obtained by multiplying the value of the nitrogen adsorption specific surface area (N2SA) of each carbon black used in combination by its usage ratio and then adding them together. In addition, when calculating this, the total of the usage ratios of each carbon black is set to 1.0.

[0022] And in this container, the above carbon black is contained in an amount of 40 to 82 parts by mass with respect to 100 parts by mass of the rubber component constituting the container. Further, the content of this carbon black is more preferably 42 parts by mass or more, and even more preferably 45 parts by mass or more, with respect to 100 parts by mass of the above rubber component. The upper limit is more preferably 80 parts by mass or less, even more preferably 75 parts by mass or less, even more preferably 70 parts by mass or less, even more preferably 65 parts by mass or less, even more preferably 60 parts by mass or less, and even more preferably 55 parts by mass or less, with respect to 100 parts by mass of the above rubber component. Note that if the amount of carbon black is less than 40 parts by mass or more than 82 parts by mass with respect to 100 parts by mass of the above rubber component, the effects of the present invention may not be obtained. Further, if the amount of carbon black is more than 82 parts by mass with respect to 100 parts by mass of the above rubber component, the insertability of the functional component into the container may decrease. Here, the content of carbon black in the present invention means the total content of all carbon blacks when a plurality of carbon blacks are included, including recycled carbon black. The same applies hereinafter.

[0023] <White filler> The container provided in the tire of the present invention preferably further contains a white filler. The white filler is not particularly limited, and any known white filler used in applications such as rubber products can be used. Specific examples of the white filler include, for example, silica, talc, mica, clay, calcium carbonate, etc. As the silica, for example, wet silica, dry silica, fumed silica, diatomaceous earth, etc. can be used. As the calcium carbonate, it is more preferable to use heavy calcium carbonate. And this white filler may be used alone or in combination of two or more. Here, this "silica" means a particulate substance composed of silicon dioxide (SiO2) or having silicon dioxide as a main component (for example, containing 80% by mass or more, and further 90% by mass or more).

[0024] And in this container, when a white filler is contained, it is preferable that the total amount of the above-described carbon black and this white filler is 40 to 85 parts by mass with respect to 100 parts by mass of the rubber component constituting the container. Further, it is more preferable that the total amount of this carbon black and white filler is more than 40 parts by mass with respect to 100 parts by mass of the above-described rubber component, still more preferably 45 parts by mass or more, and still more preferably 55 parts by mass or more. The upper limit is more preferably 80 parts by mass or less with respect to 100 parts by mass of the above-described rubber component, still more preferably 75 parts by mass or less, and still more preferably 70 parts by mass or less. Note that if the total amount of the carbon black and white filler is less than 40 parts by mass or more than 85 parts by mass with respect to 100 parts by mass of the above-described rubber component, there is a possibility that the effects of the present invention cannot be obtained. Further, if the total amount of the carbon black and white filler is more than 85 parts by mass with respect to 100 parts by mass of the above-described rubber component, the insertability of the functional component into the container may decrease. Also, the content of the white filler (the content of the white filler itself) is not limited, but it is preferably 3 to 40 parts by mass with respect to 100 parts by mass of the rubber component constituting the container. The lower limit is more preferably 10 parts by mass or more with respect to 100 parts by mass of the above-described rubber component, the upper limit is more preferably 30 parts by mass or less with respect to 100 parts by mass of the above-described rubber component, and still more preferably 20 parts by mass or less. However, the container provided in the tire of the present invention may be configured to substantially contain no white filler.

[0025] <Other components> The container provided in the tire of the present invention may further contain, as optional components, components other than the rubber component, carbon black, and white filler described above, as long as it does not significantly affect the effects of the present invention. For example, resin components (such as terpene resin, coumarone resin, indene resin, rosin resin, etc.), zinc oxide (zinc white), oil (such as aroma oil), stearic acid, wax, lecithin, anti-aging agent, plasticizer, vulcanizing agent, vulcanization accelerator, vulcanization accelerator auxiliary agent, and other various additives commonly used in rubber products can be contained in appropriate amounts. As the vulcanizing agent, sulfur is typically exemplified, but as a component other than sulfur, a compound having a cross-linking function between polymers such as peroxide may also be used. Further, these may be used in combination.

[0026] For example, the content of oil, stearic acid, zinc oxide, and resin component in this container is preferably 0.5 to 10 parts by mass, and more preferably 1.0 to 8.0 parts by mass, based on 100 parts by mass of the rubber component constituting the container. And the content of sulfur in this container is preferably 0.5 to 5.0 parts by mass based on 100 parts by mass of the rubber component constituting the container. Further, the content of the vulcanization accelerator in this container is preferably 0.3 to 3.0 parts by mass, and more preferably 0.5 to 2.0 parts by mass, based on 100 parts by mass of the rubber component constituting the container, either alone as a primary accelerator or in a blend with a secondary accelerator.

[0027] In addition, in the case where silica is used as the white filler in the tire of the present invention, in order to further improve the dispersibility of the silica, etc., a silane coupling agent may be further contained. This silane coupling agent is not particularly limited as long as it is a silane compound having a hydrolyzable group and an organic functional group. And this hydrolyzable group is not limited either, but for example, an alkoxy group, a phenoxy group, a carboxy group, an alkenyloxy group, etc. may be mentioned, and it is more preferable that the alkoxy group is an alkoxysilyl group bonded to a silicon atom. When the hydrolyzable group is an alkoxysilyl group, the carbon number of the alkoxy group is preferably 1 to 16, and more preferably 1 to 4. Examples of the alkoxy group having 1 to 4 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, etc.

[0028] In addition, the organic functional group is not limited either, but it may be a group that can form a chemical bond with an organic compound. For example, an epoxy group, a vinyl group, an acryloyl group, a methacryl group, an amino group, a sulfide group (especially, a polysulfide group (-S n -: n is an integer of 2 or more)), a mercapto group, a blocked mercapto group (protected mercapto group) (for example, an octanoylthio group), etc. may be mentioned. Among them, a sulfide group (especially, a disulfide group, a tetrasulfide group), a mercapto group, a blocked mercapto group are preferable. And such a silane coupling agent may be used alone as one kind, or two or more kinds may be used in combination. Also, this silane coupling agent is preferably a sulfur-containing silane coupling agent.

[0029] And when silica is used as the white filler described above, it is preferable to contain 1 to 20 parts by mass, and more preferably 2 to 10 parts by mass of the silane coupling agent with respect to 100 parts by mass of this silica.

[0030] <Tensile stress at 100% elongation at 100 °C (M100)> The container provided in the tire of the present invention has the configuration as described above. Furthermore, it is more preferable that the tensile stress (M100) at 100% elongation at 100 °C of this container is 5.0 MPa or less. This is because the container and the like are likely to have sufficient durability to withstand the forces and impacts caused by the rotation of the tire during driving. This M100 is more preferably 4.5 MPa or less, still more preferably 4.0 MPa or less, still more preferably 3.5 MPa or less, and still more preferably 3.0 MPa or less. The lower limit is more preferably 0.8 MPa or more, still more preferably 1.0 MPa or more, and still more preferably 1.3 MPa or more because it becomes easier to further suppress the detachment of functional parts.

[0031] Here, this M100 is a value confirmed by a method of collecting a predetermined rubber test piece (for example, dumbbell No. 7 shape) from the container, performing a tensile test on this rubber test piece at a tensile speed of 500 mm / min in accordance with JIS K6251:2017, and measuring the tensile stress (MPa: M100) at 100% elongation at 100 °C. And in the configuration as described above, this M100 can be made within the above-mentioned range by adjusting the ratio of each component and the like.

[0032] [Functional parts] As functional components to be accommodated in the tire accommodating body of the present invention, there is no limitation as long as they have a sensor function for detecting tire information and can have a contact surface that contacts the inner surface of the tread portion of the tire. For example, electronic components including various sensors, transmitters, receivers, control circuits, batteries, etc. are exemplified. Examples of tire information detected and acquired by the sensor function include the internal temperature and internal pressure (air pressure) of a pneumatic tire, the wear amount of the tread portion, etc. A temperature sensor or a pressure sensor can be used for measuring the internal temperature and internal pressure. For detecting the wear amount of the tread portion, a sensor element using a piezoelectric element is disposed on the contact surface, and a functional component that detects an output voltage corresponding to the tire deformation during running by the sensor element and detects the wear amount of the tread portion based on the output voltage is preferably exemplified. That is, it is more preferable from the viewpoint of detecting the wear amount of the tread portion that the sensor function of this functional component is a sensor function using a piezoelectric element as the sensor element. In addition, it is also possible to use an acceleration sensor or a magnetic sensor.

[0033] [Tire] The tire of the present invention has, for example, as shown in FIG. 1, a tread portion 1 extending in the tire circumferential direction and forming an annular shape, a pair of sidewall portions 2, 2 disposed on both sides of the tread portion 1 (both ends in the tire width direction), and a pair of bead portions 3, 3 disposed on the inner side in the tire radial direction of the pair of sidewall portions 2. An embodiment is shown.

[0034] And in this embodiment, at least one carcass layer 4 is mounted between the pair of bead portions 3, 3. The carcass layer 4 includes a plurality of reinforcing cords extending in the tire radial direction, and is folded back from the inner side to the outer side of the tire around the bead core 5 disposed in each bead portion 3. A bead filler 6 made of a rubber composition having a triangular cross section is disposed on the outer circumference of the bead core 5.

[0035] On one side, one or more (preferably multiple) belt layers 7 are arranged on the outer peripheral side of the carcass layer 4 in the tread portion 1. These belt layers 7 include a plurality of reinforcing cords inclined in substantially the same direction with respect to the tire circumferential direction (the reinforcing cords are embedded), and when including a plurality (for example, two layers) of belt layers 7, the reinforcing cords are arranged so as to cross each other between these layers. In the belt layer 7, the inclination angle of the reinforcing cord with respect to the tire circumferential direction is set in the range of 10° to 60° at the smaller angle, for example. As the reinforcing cord of the belt layer 7, a steel cord is preferably used. On the outer peripheral side of the belt layer 7, for the purpose of improving high-speed durability, at least one belt cover layer 8 formed by arranging reinforcing cords at an angle of, for example, 5° or less with respect to the tire circumferential direction may be arranged. As the reinforcing cord of the belt cover layer 8, organic fiber cords such as nylon and aramid are preferably used.

[0036] Furthermore, a tread rubber layer 15 is arranged in the tread portion 1. The tread rubber layer 15 includes at least a cap tread rubber layer 15A. In this embodiment, it is composed of two layers, namely, the cap tread rubber layer 15A forming the tread surface of the tread portion 1 and the under tread rubber layer 15B located on the inner side in the tire radial direction of the cap tread rubber layer 15A. Note that the tread rubber layer 15 may include an earth tread made of conductive rubber exposed on the tire contact surface and wing tips respectively arranged at both ends in the tire width direction of the cap tread rubber layer 15A.

[0037] The constituent components of the tire of the present invention (components constituting each member such as the tread portion and each layer such as the belt layer) are not particularly limited, and known components for constituting a tire such as rubber components can be arbitrarily used. Also, the tire size and the use of the tire are not particularly limited, and it is possible to use various tires such as passenger car tires, truck bus tires, and off-road tires.

[0038] The tire of the present invention is provided with a container having the configuration as described above on the inner surface of the tread portion of the tire in such an embodiment. The arrangement position of this container is not particularly limited as long as it is the inner surface of the tread portion of the tire, and it may be a position that does not pass through the center point in the tire width direction on the inner surface of the tread portion of the tire.

[0039] In addition, the tire of the present invention is preferably a pneumatic tire. As the gas filled in this pneumatic tire, for example, air, nitrogen, argon, an inert gas such as helium, and other gases can be used.

[0040] The tire (tire with functional components) of the present invention having the above configuration has an excellent sensing intensity of the sensor function of the functional components provided on the inner surface of the tread portion of the tire, and furthermore, the durability of the container for housing this functional component is also excellent. That is, even if repeated deformation occurs in the container due to rotation, deformation of the tread portion, impact, etc. during tire running, damage (such as cracking or separation of members) of the container is less likely to occur.

[0041] Hereinafter, examples of the present invention will be described. However, the present invention is not limited to the following examples, and various modifications are possible within the technical idea of the present invention.

Examples

[0042] (Production and evaluation of tires with functional components) Containers having the compositions shown in Table 1 below and the shapes shown in FIGS. 2 to 3 were produced, and each of these containers was bonded and fixed to the inner surface of the tread portion of a tire of tire size 235 / 55R17 96V with an adhesive as shown in FIG. 1. Further, a functional component using a piezoelectric element as a sensor element was mounted on the container so that the piezoelectric element was arranged on the contact surface in contact with the inner surface of the above tire, and tires with various functional components were produced.

[0043] Then, for the tires with functional components obtained in Reference Example 1, Comparative Examples 1 to 6, and Examples 1 to 5, the rubber hardness (HS) and tensile stress at 100% elongation (M100) of the housing were measured as follows, and the sensing strength, detachability (difficulty of detachment), insertability, and durability of the housing of the functional components were evaluated.

[0044] <Rubber hardness (HS)> From the housing part in the housing of each obtained tire with a functional component, a dumbbell-shaped No. 7 rubber test piece (thickness 1.0 ± 0.1 mm) was taken, and the rubber hardness (HS) of this rubber test piece was measured at a temperature of 20 °C using a Type A durometer (manufactured by Toyo Seiki Seisakusho Co., Ltd.) in accordance with JIS K6253-3:2012. These results were shown in the middle row of Table 1 below.

[0045] <Tensile stress at 100% elongation (M100)> From the housing part in the housing of each obtained tire with a functional component, a dumbbell-shaped No. 7 rubber test piece (thickness 1.0 ± 0.1 mm) was taken, and for this rubber test piece, a tensile test was carried out at a tensile speed of 500 mm / min in accordance with JIS K6251:2017, and the tensile stress at 100% elongation (MPa: M100) was measured at 20 °C and 100 °C. These results were shown in the middle row of Table 1 below.

[0046] <Sensing strength> For each obtained tire with a functional component, it was assembled on a wheel with an air pressure of 230 kPa and run on a drum at a speed of 30 km / h using a drum tester, and the peak height of the waveform detected by the sensor element of the functional component was measured. These results were shown in the lower row of Table 1 below. The results were expressed as an index with the value of Reference Example 1 being 100.

[0047] <Detachability of functional component> For each tire with the obtained functional components, it was assembled onto a wheel with an air pressure of 360 kPa and run on a drum tester. It was accelerated to a speed of 260 km / h in the first 10 minutes, and then accelerated by 10 km / h every 10 minutes. And the speed at which the functional components fell off from the housing was taken as the test result. This result was shown in the lower part of Table 1 below. The results were expressed as an index with the value of Reference Example 1 being 100.

[0048] <Insertability> Whether the same functional components could be inserted into each housing joined and fixed to the inner surface of the tire at one time was evaluated with ○×. This result was shown in the lower part of Table 1 below.

[0049] <Durability of the housing> For each obtained tire with functional components, as a pretreatment, oxygen was enclosed at 350 kPa and stored at 80 °C for 5 days. Then it was assembled onto a wheel and a chamber running test was carried out on a drum tester with the running condition of increasing from 81 km / h by 10 km / h every 2 hours until 150 km / h. And those with the housing broken were marked as ×, and those without breakage were marked as 〇. Note that the breakage of this housing was defined as the state where the sensor function of the functional components could not be exerted due to cracks or detachment of the housing part of the housing. This result was shown in the lower part of Table 1 below.

[0050]

Table 1

[0051] The detailed contents of each component, etc. in Table 1 above are as follows. ·NR: Natural rubber (SIR20, manufactured by PT. PANTJA SURYA) ·IIR: Butyl rubber (EXXON Bromobutyl 2255, manufactured by ExxonMobil chemical company) ·CB1: Carbon black (GPF, nitrogen adsorption specific surface area (N2SA): 35m 2 / g, Nitron #GN: manufactured by Shin Nippon Carbon Co., Ltd.) · CB2: Carbon black (HAF, Nitrogen adsorption specific surface area (N2SA): 93 m 2 / g, Seast KH: manufactured by Tokai Carbon Co., Ltd.) · Zinc oxide: Silver Ridge R (manufactured by Toho Zinc Co., Ltd.) · Stearic acid: Bead Stearic Acid Kiri (manufactured by Chiba Fatty Acids Co., Ltd.) · Resin (resin component): C5 resin (Homogenizing Agent H40MSF, manufactured by SHANDONG YANGGU HUATAI CHEMICAL Co., Ltd.) · Aroma oil: Aroma oil (Diana Process NH-70S, manufactured by Idemitsu Kosan Co., Ltd.) · Sulfur: Sulfax 5 (manufactured by Tsukimi Chemical Industry Co., Ltd.) · Vulcanization accelerator: Nocceler DM-PO (manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.) · Silica 1: Silica (ULTRASIL VN3GR, CTAB specific surface area 170 m 2 / g: manufactured by Evonik Industries AG)

[0052] From these results, in a container composed of a rubber component containing 65% by mass or more of IIR and having a content ratio of NR of 35% by mass or less, by setting a predetermined amount of carbon black, it was shown that the sensing strength, drop-off property, and insertability of the functional component were all improved, and the durability of the container was also improved (Examples 1 to 5). On the other hand, when the ratio of butyl rubber or the content of carbon black in the rubber component was low, the sensing strength and drop-off property of the functional component decreased (Comparative Examples 1, 2, 4), and when the content of carbon black was high, it was also shown that the insertability of the functional component and the durability of the container decreased (Comparative Examples 3, 6). Also, when silica was used as a substitute for carbon black, the insertability of the functional component decreased (Comparative Example 5).

[0053] Furthermore, in the same manner as described above, containers having the compositions shown in Table 2 below and having the shapes shown in FIGS. 2 to 3 were produced. Each of these containers was joined and fixed to the inner surface of the tread portion of a tire of tire size 235 / 55R17 96V as shown in FIG. 1. Further, the same functional components using a piezoelectric element as the sensor element were mounted on the containers to produce tires with various functional components.

[0054] Then, for the tires with functional components obtained in Reference Example 2, Comparative Example 7, and Examples 9 to 18, the tensile stress (M100) at 100% elongation at 100°C of the containers was measured in the same manner as described above, and the sensing strength of the functional components was evaluated. Further, the durability of the containers was tested in the same indoor running test under the running conditions of increasing the speed by 10 km / h every 2 hours from 81 km / h, and the speed at which the container broke was taken as the test result. The results are shown in the middle and lower rows of Table 2 below. Note that the results of the sensing strength of the functional components and the durability of the containers are both expressed as indices with the value of Reference Example 2 taken as 100.

[0055]

Table 2

[0056] The detailed contents of each component, etc. in Table 2 above are as follows: Components overlapping with those in Table 1 are the same as those in Table 1, and components not described in Table 1 are as follows. · CB3: Carbon black (FEF, nitrogen adsorption specific surface area (N2SA): 42 m 2 / g, Seast SO: manufactured by Tokai Carbon Co., Ltd.) · Silica 2: Silica (ULTRASIL 115GR, CTAB specific surface area 114 m 2 / g: manufactured by Evonik Industries AG) · Clay: T clay (manufactured by Saitama Minerals Co., Ltd.) · Calcium carbonate: Heavy calcium carbonate (manufactured by Maruo Calcium Co., Ltd.) · Talc: MH (manufactured by Nippon Talc Co., Ltd.) · Silane coupling agent: Si69 (manufactured by Evonik Industries AG)

[0057] From these results, it was shown that the same effects were exhibited even when silica, clay, calcium carbonate, or talc was used as a white filler together with carbon black in a container composed of a rubber component containing 70% by mass or more of IIR and having an NR content of 30% by mass or less (Examples 9 to 18). On the other hand, when the carbon black content and the total amount of carbon black and silica were low, the sensing intensity of the functional component decreased (Comparative Example 7).

Explanation of Signs

[0058] 100 Tire 1 Tread portion 2 Sidewall portion 3 Bead portion 4 Carcass layer 5 Bead core 6 Bead filler 7 Belt layer 8 Belt cover layer 11 Tire circumferential groove 12 Inner surface of the tread portion of the tire 20 Functional component 21 Contact surface (piezoelectric element) 30 Container 31 Base 32 Sidewall 33 Accommodating portion

Claims

1. A tire having a housing that houses functional components on the inner surface of the tread portion of the tire, The functional component has at least a contact surface that contacts the inner surface of the tire and a sensor function for detecting tire information, The housing is made of a rubber component, the rubber component contains 60% by mass or more of butyl rubber (IIR) and the content ratio of natural rubber (NR) is 40% by mass or less. Further, 40 to 60 parts by mass of carbon black is contained per 100 parts by mass of the rubber component, and the total amount of the carbon black and the white filler is 40 to 60 parts by mass per 100 parts by mass of the rubber component. A tire in which the tensile stress (M100) at 100% elongation at 100 °C of the housing is 0.8 MPa or more and 3.2 MPa or less.

2. The tire according to claim 1, wherein the white filler is at least one selected from the group consisting of silica, talc, mica, clay, and calcium carbonate.

3. The average value of the nitrogen adsorption specific surface area (N 2 SA) of the carbon black is 10 m 2 / g or more and 50 m 2 / g or less. The tire according to claim 1 or 2.

4. The tire according to claim 1 or 2, wherein the housing is fixed to the inner surface of the tire.

5. The tire according to claim 4, wherein the housing is fixed to the inner surface of the tire by an adhesive.

6. The tire according to claim 1 or 2, wherein the sensor function of the functional component is a sensor function using a piezoelectric element as a sensor element.

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