TIRES

Abstract

An object of the present invention is to provide a tire having improved overall grip performance during turning. A tire is provided comprising a tread portion, a sidewall, a carcass, and a stripe apex, wherein the stripe apex is present on an inner side of the sidewall in a tire axial direction or on an inner side of a roll-back portion of the carcass in the tire axial direction. The tread portion, the sidewall, and the stripe apex are formed from a rubber composition comprising a rubber component, wherein, when L represents a tire elevation ratio, L is 0.60 or more, the rubber composition constituting the tread portion comprises an organic crosslinking agent, and wherein, when AE1 in mass % represents an acetone-extractable amount of the rubber composition constituting the tread portion,AE2 in mass% represents an acetone-extractable amount of the rubber composition forming the sidewall, and AE3 in mass% represents an acetone-extractable amount of the rubber composition forming the strip apex, AE1>AE2>AE3.

Description

TECHNICAL FIELD

[0001] The present invention relates to a tire. STATE OF THE ART

[0002] In recent years, as vehicles have demonstrated high performance, there has also been a demand for improved cornering grip performance in a tire for a four-wheeled automobile. For example, Patent Document 1 describes that the fuel efficiency and wet grip performance of a tire are improved with a rubber composition comprising a polymer modified with a divalent phenol compound and silica. PRIOR ART DOCUMENTPatent document

[0003] Patent Document 1: JP 2023-155706 A SUMMARY OF THE INVENTION PROBLEM TO BE SOLVED BY THE INVENTION

[0004] However, Patent Document 1 does not consider grip performance when turning.

[0005] An object of the present invention is to provide a tire having improved grip performance when turning. MEANS TO SOLVE THE PROBLEM

[0006] The present invention relates to: Tire comprising a tread portion, a sidewall, a carcass and a strip apex, wherein the stripe apex is present on an inner side of the sidewall in a tire axial direction or on an inner side of a roll-back portion of the carcass in the tire axial direction, wherein the tread portion, the sidewall and the strip apex are formed from a rubber composition comprising a rubber component, where, when L represents a tire elevation ratio, L is 0.60 or more, wherein the rubber composition forming the tread portion comprises an organic crosslinking agent, and where, if AE1 represents in mass% an acetone-extractable amount of the rubber composition forming the tread portion, AE2 in mass% represents an acetone-extractable amount of the rubber composition forming the sidewall and AE3 represents in mass% an acetone-extractable amount of the rubber composition forming the strip apex, AE1>AE2>AE3. EFFECT OF THE INVENTION

[0007] According to the present invention, a tire is provided having improved grip performance when turning. SHORT DESCRIPTION OF THE CHARACTERS Fig. 1 is a cross-sectional view taken through a tire rotational axis of a tire according to an embodiment of the present invention. Fig. 2 is a schematic development view of a tread portion showing an embodiment of the present invention. EMBODIMENTS FOR CARRYING OUT THE INVENTION

[0008] The tire which is an embodiment of the present invention is a tire comprising a tread portion, a sidewall, a carcass, and a stripe apex, wherein the stripe apex is present on an inner side of the sidewall in a tire axial direction or on an inner side of a roll-back portion of the carcass in the tire axial direction, wherein the tread portion, the sidewall, and the stripe apex are formed of a rubber composition comprising a rubber component, wherein, when L represents a bump ratio of the tire, L is 0.60 or more, wherein the rubber composition constituting the tread portion comprises an organic crosslinking agent, and wherein, when AE1 represents an acetone-extractable amount of the rubber composition constituting the tread portion, AE2 represents an acetone-extractable amount of the rubber composition constituting the sidewall,and AE3 in mass% represents an acetone-extractable amount of the rubber composition forming the strip apex, AE1>AE2>AE3.

[0009] Although not intended to be bound by any theory, a reason why grip performance in turning is improved in the tire of the present embodiment is believed, for example, as follows.

[0010] First, (1) when a steering wheel is turned while a load is applied to the tire, strain is transmitted from a rim to the sidewall and from the sidewall to the tread portion. Since there is a large difference in rigidity between the rim and the sidewall formed of the rubber composition, strain is less likely to be transmitted from the rim to the sidewall, resulting in deteriorated ground contact property of the tread portion. Therefore, it is believed that strain from the rim is easily transmitted to the sidewall due to the presence of the stripe apex formed of the rubber composition on the inner side of the sidewall in the tire axial direction or on the inner side of the roll-back portion of the carcass in the tire axial direction.

[0011] In addition, (2) it is believed that by setting the elevation ratio L of the tire to 0.60 or more, ground contact property of the tread portion on a road surface is improved, which contributes to improving grip performance when turning.

[0012] Furthermore, (3) it is believed that by incorporating an organic crosslinking agent in the rubber composition constituting the tread portion, reinforcing properties between polymer chains are improved with the intervention of carbon bonds, and appropriate rigidity against heat and deformation generated during running can be ensured, so that followability on the road surface is improved, which contributes to improving grip performance.

[0013] (4) It is assumed that by adjusting the rubber composition constituting the sidewall to have appropriate rigidity, the sidewall flexes during vehicle travel, which contributes to improving the ground contact property of the tread portion. In the present embodiment, it is assumed that by making AE1>AE2 and making the rigidity of the tread portion lower than the rigidity of the sidewall, the ground contact property of the tread portion is ensured, which contributes to improving grip performance during turning.

[0014] Furthermore, (5) it is assumed that by making AE1>AE2>AE3, strain can be transferred in stages from the rim to the sidewall and from the sidewall to the tread portion, so that the tread portion can be efficiently deformed, which contributes to improving grip performance during turning.

[0015] It is believed that with the cooperation of the above (1) to (5), a remarkable effect of improving grip performance during turning is achieved.

[0016] The elevation ratio L is preferably 0.70 or more, and more preferably 0.80 or more. This is because it is believed to improve the ground contact property of the tread portion on the road surface and further enhance grip performance during turning.

[0017] A product (Hs × L) of a rubber hardness Hs of the rubber composition constituting the tread portion and L is preferably less than 49.

[0018] It is believed that by setting Hs × L to less than 40, the rubber hardness of the tread portion can be appropriately reduced in proportion to the land ratio, and a difference in rigidity between the tread portion and the sidewall or the strip apex can be reduced, thereby further improving grip performance during turning.

[0019] If 30 °CE* T (MPa) represents a complex elastic modulus at 30 °C of the rubber composition constituting the tread portion, is a product (30 °CE* T × L) from 30 °CE* T and L preferably less than 20.

[0020] It is assumed that by setting 30 °CE* T× L to less than 20, the stiffness of the tread portion relative to the elevation ratio can be appropriately reduced, and the difference in stiffness between the tread portion and the sidewall or the strip apex can be reduced, thereby further improving grip performance during turning.

[0021] A product (AE3 × L) of AE3 and L is preferably greater than 3.5.

[0022] It is believed that by setting AE3 × L to greater than 3.5, stiffness of the strip apex relative to the elevation ratio can be appropriately increased and a difference in stiffness between the strip apex and the rim can be reduced, thereby further improving grip performance during turning.

[0023] If 70 °CE* S (MPa) represents a complex elastic modulus at 70 °C of the rubber composition forming the sidewall, is a product (70 °CE* S× L) from 70 °CE* S and L preferably greater than 5.0.

[0024] It is assumed that by setting 70 °CE* S × L to greater than 5.0, stiffness of the sidewall relative to the elevation ratio can be appropriately increased, a difference in stiffness between the sidewall and the strip apex can be reduced, and strain can be more easily transmitted to the tread portion, thereby further improving grip performance during turning.

[0025] The organic crosslinking agent is preferably a dithiocarbamic acid-based compound.

[0026] It is believed that when the rubber composition constituting the tread portion comprises a dithiocarbamic acid-based compound, splitting due to heat or strain during driving is less likely to occur, reinforcing properties between polymer chains are improved, appropriate rigidity against heat and strain generated during driving can be ensured, and followability on the road surface is improved, thereby further improving grip performance during turning.

[0027] The rubber composition forming the sidewall preferably comprises 20 mass% or more of a butadiene rubber in the rubber component.

[0028] It is believed that when the rubber composition in the sidewall comprises a certain amount or more of a butadiene rubber, a glass transition temperature (Tg) of the rubber composition does not become too low and a certain level of heat generation can be maintained even during turning, thereby further improving grip performance during turning.

[0029] The rubber composition forming the sidewall preferably comprises a resin component. It is believed that when the rubber composition comprises a resin component, grip performance during turning is further improved.

[0030] The total amount of styrene in the rubber component of the rubber composition constituting the tread portion is preferably 20 mass% or more. It is believed that by adjusting the total amount of styrene in the rubber component within the above-described range, the number of styrene groups increases and heat generation is improved, thereby further improving grip performance.

[0031] In the tread portion, with a tire equator centered, when Lo represents a bump ratio of a ground contact surface of an outer tread portion constituting an end side outside a vehicle and Li represents a bump ratio of a ground contact surface of an inner tread portion constituting the end side outside the vehicle, an absolute value of a difference (Lo-Li) between Lo and Li is preferably larger than 0 and smaller than 0.2.

[0032] It is assumed that when the absolute value of Lo-Li is greater than 0 and less than 0.2, the difference in elevation ratio between the inner tread portion and the outer tread portion is small and a ground contact area on the surface of the tread portion becomes large when turning, thus improving grip performance when turning.

[0033] AE3 is preferably 4.0 mass% or more.

[0034] It is believed that when the acetone extractable amount of the rubber composition constituting the strip apex is high at a certain level, the stiffness of the strip apex can be appropriately increased and the difference in stiffness between the strip apex and the rim can be reduced, thereby further improving the grip performance during turning.

[0035] AE1 × L is preferably 14.0 or more. It is believed that even if the amount of acetone extractable from the tread portion is small, grip performance can be ensured by increasing the elevation ratio L.

[0036] The rubber composition forming the tread portion preferably comprises carbon black with an average primary particle size of 30 nm or less. It is believed that when the rubber composition comprises carbon black with a small particle size, high heat generation due to friction between particles can be achieved, thus further improving wet grip performance. [Definitions]

[0037] A “standardized condition” is a condition in which a tire is rim-mounted on a standardized rim and filled with air at a standardized internal pressure and no load is applied.

[0038] A "dimension of any part of the tire" is, unless otherwise specified, a value specified in a standardized condition for one appearing on the outer surface of the tire, while for one present inside the tire or for one on a tire cut surface, it is a value specified in a condition in which, for example, the tire is cut along a plane containing a tire axis of rotation and the cut tire piece is held to a rim width of a standardized rim.

[0039] A "standardized rim" is a rim in a standards system containing a standard on which the tire is based, which is defined by the standard for each tire. For example, a "standardized rim" refers to a standard rim of an applicable size described in the "Jatma Year Book" of JATMA (The Japan Automobile Tire Manufacturers Association, Inc.), the "Measuring Rim" described in the "STANDARDS MANUAL" of ETRTO (The European Tire and Rim Technical Organization), or the "Design Rim" described in the "YEAR BOOK" of TRA (The Tire and Rim Association, Inc.), which are referred to in that order. If there is an applicable size at the time of reference, the rim conforms to its standard.In addition, in a case of tires not defined by the standard, the standardized rim shall refer to a rim that can be mounted on the tire and whose width is the narrowest among rims that have the smallest diameter that can maintain internal pressure (ie, does not cause air leakage between the rim and the tire).

[0040] A "standardized internal pressure" is an air pressure in a system of standards containing a standard on which the tire is based, which is defined by the standard for each tire. It refers, for example, to a "MAXIMUM AIR PRESSURE" in JATMA, "INFLATION PRESSURE" in ETRTO or a maximum value described in table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in TRA, referred to in this order, as in the case of the standardized rim, and if there is an applicable size at the time of reference, the standardized internal pressure conforms to its standard.In addition, in the case of tires not defined by the standard, the standardized internal pressure shall refer to a standardized internal pressure (250 kPa or more) of another tire size (specified in the standard) for which the standardized rim is described as a standard rim, and if multiple standardized internal pressures of 250 kPa or more are described, it shall refer to a minimum value among them.

[0041] A “standardized load in kg” is a load in a standard system containing a standard on which the tire is based, which is defined by the standard for each tire, for example a “MAXIMUM LOAD CAPACITY” at JATMA, a “LOAD CAPACITY” at ETRTO or a maximum value described in the table “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES” at TRA, referred to in this order, as in the case of a standardized rim and a standardized internal pressure, and if there is an applicable size at the time of reference, the load conforms to its standard. Then, in the case of tires not defined by the standard, the separately calculated maximum load capacity W L defined as a standardized load.

[0042] The “maximum load capacity W L “ is calculated by the following equations. Where “V” is a virtual volume of the tire in mm 3of a tire, "Dt" is a tire outer diameter in mm in a standardized state, "Ht" is a tire section height in mm in a tire radial direction in a cross-section of the tire in a plane containing a tire rotational axis, and "Wt" is a tire section width in mm in a standardized state. Where R represents a rim diameter of the tire, Ht can be calculated by (Dt-R) / 2. Wt is a value obtained by excluding patterns or characters on the side surface of the tire, if any. In addition, the "maximum load capacity" has the same meaning as the standardized load described above. WL=0.000011×V+175 V={(Dt / 2)2−(Dt / 2−Ht)2}×π×Wt

[0043] A "ground contact area" is a tread area obtained from a contour when a tire is pressed against the ground. It is obtained by mounting the tire on a standardized rim, filling it with a standardized internal pressure, and allowing the tire to stand at 25°C for 24 hours. This is followed by painting a tire tread surface with ink, applying a standardized load (load equal to the maximum load capacity) to the tire to press the tire vertically against a cardboard (a camber angle of 0°), and transferring the ink. A ground contact area area refers to a total ground contact area. The total ground contact area can be determined as an average value of five areas obtained by performing the above-described transfer process at a total of five locations by rotating a tire by 72°.

[0044] An "effective ground contact area" is a tread area where a tire contacts the ground when the tire is pressed against the ground. It is obtained by mounting the tire on a standardized rim, filling it with a standardized internal pressure, and allowing the tire to stand at 25°C for 24 hours. This is followed by painting a tire tread surface with ink, applying a standardized load (load equal to the maximum load capacity) to the tire to press the tire vertically against a cardboard (a camber angle of 0°), and transferring the ink. An effective ground contact area area refers to an effective ground contact area. The effective ground contact area can be determined as an average value of five areas obtained by performing the above-described transfer process at a total of five locations by rotating a tire by 72°.

[0045] An "elevation ratio L" is calculated from the total ground contact area of ​​the ground contact area and the effective ground contact area of ​​the effective ground contact area using the following equation. It is expressed as 0 to 1.0. Elevation ratio L=(effective ground contact area / total ground contact area)

[0046] A "tread portion" is a member including a portion constituting a ground contact surface of a tire, and in a case where the tire includes a member constituting a tire skeleton made of steel or a textile material, such as a belt layer, a belt reinforcing layer, a carcass, and the like, on a cross section in a tire radial direction, a member disposed on an outer side thereof in the tire radial direction.

[0047] A "sidewall" is a member including a portion forming a side surface of a tire, and is arranged on an inner side in a tire radial direction with respect to a tread portion and on an outer side in the tire radial direction with respect to a bead portion.

[0048] A “carcass” is an element that contains a section of a cord layer covered with a rubber that forms a skeleton of a tire.

[0049] An “acetone extractable amount (AE)” is a value calculated by the following equation by immersing each vulcanized rubber test piece in acetone at normal temperature (around 25 °C) for 72 hours to extract a soluble component in accordance with JIS K 6229, and measuring a mass of each test piece before and after extraction. Acetone extractable amount (mass −%) = {(mass of rubber test piece before extraction − mass of rubber test piece after extraction) / (mass of rubber test piece before extraction)} × 100

[0050] A "hardness of a rubber composition" is a Shore hardness (Hs) measured under a condition of a temperature of 23°C using a Type A durometer in accordance with JIS K 6253-3:2012. When preparing a test sample from a tire tread portion, the hardness is measured by cutting out a rubber composition from a surface side constituting a tire ground contact surface so that a tire radial direction becomes a thickness direction, and pressing the Type A durometer against the sample from the ground contact surface side.

[0051] A "loss tangent and complex elastic modulus of a rubber composition" is a loss tangent (tan δ) and complex elastic modulus E* (MPa) under each condition, as measured in a stretching mode using a dynamic viscoelasticity measuring device (e.g., EPLEXOR series, manufactured by gabo Systemtechnik GmbH). A sample for measuring dynamic viscoelasticity is a rubber composition with a length of 20 mm x 4 mm x 1 mm thickness. In a case where the sample is prepared by cutting from a tire, if a member from which the sample is prepared is a tread portion, a belt reinforcing layer, a belt layer, or an inner liner, a longitudinal direction of the sample is configured to coincide with a tire circumferential direction, and a thickness direction of the sample is configured to coincide with a tire radial direction.When the member from which the specimen is made is a sidewall, clinch section, bead apex, or strip apex, a longitudinal direction of the specimen is configured to coincide with a tangential direction to a tire circumference, and a thickness direction of the specimen is configured to coincide with a tire width direction. In either case, the specimen is manufactured so that its dimensions are as close as possible to predetermined dimensions. This is because strain applied to the specimen is normalized with respect to length and normalized to a tan δ and E* to be measured at the width and thickness of the specimen, respectively, so that it is assumed that there is no influence due to the size of the specimen.In addition, when the sample cannot be prepared by cutting it out from the tire, an unvulcanized rubber composition obtained by kneading is vulcanized into a test rubber sheet, and a sample cut out from the rubber sheet may be the sample.

[0052] "30 °CE*" is a complex elastic modulus E* (MPa) measured under a condition of a temperature of 30 °C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain of ± 1%, and an elongation mode.

[0053] "70 °CE*" is a complex elastic modulus E* (MPa) measured under a condition of a temperature of 70 °C, a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ± 1%, and an elongation mode.

[0054] A "total styrene content in a rubber component" is a total content in mass% of styrene units contained in 100 mass% of a rubber component, which is a value obtained by multiplying a styrene content in mass% by a mass fraction in a rubber component to obtain a calculated value for each of the respective rubber components and summing these values. Specifically, it is calculated by Σ(styrene content (mass%) of each styrene-containing rubber × content (mass%) of each styrene-containing rubber in the rubber component / 100). For example, if the rubber component consists of 30 mass% of a first SBR (styrene content: 25 mass%), 60 mass% of a second SBR (styrene content: 27.5 mass%), and 10 mass% of a BR, a total styrene amount (S) in 100 mass% of the rubber component is 24.0 mass% (= 25 × 30 / 100 + 27.5 × 60 / 100 + 0 × 10 / 100).

[0055] A “rubber component of a rubber composition” is a component that contributes to crosslinking in the rubber composition and generally has a weight average molecular weight (Mw) of 10,000 or more.

[0056] A "land section" is a section of a tread where a tire contacts the ground when the tire is pressed against the ground, and a section of the tread that forms the effective ground contact area.

[0057] A “styrene content” is a value determined by 1 H-NMR measurement, and is applied, for example, to a rubber component having a repeating unit derived from styrene, such as an SBR and the like (styrene unit-containing rubber).

[0058] A “vinyl content (cis-1,2-bonded butadiene unit amount)” is a value calculated by infrared absorption spectrometry in accordance with JIS K 6239-2:2017, and is applied to a rubber component having a repeating unit derived from butadiene, such as an SBR, a BR, and the like.

[0059] A “cis content (cis-1,4-bonded butadiene unit amount)” is a value calculated by infrared absorption spectrometry according to JIS K 6239-2:2017, and is applied to a rubber component having a repeating unit derived from butadiene, such as a BR and the like.

[0060] A "weight-average molecular weight (Mw)" can be calculated with respect to a standard polystyrene based on measured values ​​obtained by gel permeation chromatography (GPC) (e.g., GPC-8000 series manufactured by Tosoh Corporation, detector: differential refractometer, column: TSKgel (registered trademark) SuperMultiporeHZ-M manufactured by Tosoh Corporation). For example, it is applied to an SBR, a BR, a plasticizer, and the like.

[0061] A "nitrogen adsorption specific surface area (N2SA) of carbon black" is measured according to JIS K 6217-2:2017. A "nitrogen adsorption specific surface area (N2SA) of silica" is measured by the BET method according to ASTM D3037-93.

[0062] An "average primary particle size" is calculated by taking the arithmetic mean of particle sizes of 400 particles photographed with a transmission or scanning electron microscope. Regarding particle size, in a case where the particle is substantially circular, a diameter of the circle is defined as a particle size; in a case where it is needle- or rod-shaped, a minor axis is defined as a particle size; and in other cases, an equivalent circle diameter calculated from an electron microscope image is defined as a particle size. The equivalent circle diameter is calculated as "the positive square root of 4 × (particle area) / π." The average primary particle size is applied to silica, carbon black, etc.

[0063] A "plasticizer content" also includes an amount of a plasticizer contained in an extended rubber component previously extended with the plasticizer, such as oil, a resin component, a liquid rubber component, and the like. The same applies, for example, to an oil content, a resin component content, and a liquid rubber content. For example, an extender oil is included in the oil content when an extender component is oil.

[0064] A “softening point of a resin component” is specified as a temperature at which a ball falls when the softening point defined in JIS K 6220-1:2015 7.7 is measured with a ring-and-ball softening point measuring device. [Tires]

[0065] The tire according to an embodiment of the present invention will be described below with reference to the drawings. Furthermore, the embodiments shown below are merely examples, and the tire of the present embodiment is not limited to the following embodiments.

[0066] Fig. 1 illustrates a tire which is an embodiment of the present invention. Fig. Figure 1 shows a portion of a cross-section of a tire when cut along a plane containing a tire rotation axis. In Fig. 1, a vertical direction is a tire radial direction, a horizontal direction is a tire axial direction, and a direction perpendicular to a paper surface is a tire circumferential direction. In Fig. 1, the alternating long and short dashed line CL represents a tire equator.

[0067] The tire in Fig.1 includes a tread portion 1 that contacts the ground during driving, a sidewall 2 extending toward an outer side in a tire radial direction, a bead portion 3, a carcass 4, and a stripe apex 5. The stripe apex 5 is provided on an inner side of the sidewall 2 in a tire axial direction.

[0068] As in Fig.1, the tire has a belt layer 16 on an inner side of the tread portion 1 in a tire radial direction. The carcass 4 and an inner liner 7 are laminated to the lower portion of the belt layer 16. Furthermore, a tape layer 6 may be provided between the tread portion 1 and the belt layer 16. The bead portion 3 includes a bead core 14 and a bead apex 13 extending from the core to an outer side in the tire radial direction. The bead apex 13 is tapered outward in the tire radial direction. In the bead portion 3, a clinch portion 10, which comes into contact with a rim 8 upon assembly, is provided on an outer side of the carcass 4, and the clinch portion 10 is formed of a rubber composition comprising a rubber component. A rim bead band 9 may be present between the clinch section 10 and the rim 8. <<Laufflächenabschnitt> >

[0069] The tread portion 1 is formed of a rubber composition comprising a rubber component and an organic crosslinking agent. The tread portion 1 may be a single rubber layer or may comprise two or more rubber layers. When the tread portion comprises two or more rubber layers, each of the physical properties, such as an AE amount, a rubber hardness, and the like, of the rubber composition constituting the tread portion may be satisfied in any of the rubber layers, but preferably in a layer whose outer surface forms a tread surface (rubber cap layer).

[0070] The acetone-extractable amount AE1 of the rubber composition constituting the tread portion is larger than the acetone-extractable amount AE2 of the rubber composition constituting the sidewall, and in particular, from the viewpoint of the effects of the present invention, it is preferably 12.0 mass % or more, more preferably 15.0 mass % or more, even more preferably 17.0 mass % or more, even more preferably 20.0 mass % or more, even more preferably 22.0 mass % or more, even more preferably 25.0 mass % or more, even more preferably 27.0 mass % or more, and particularly preferably 30.0 mass % or more. Moreover, from the viewpoint of fuel efficiency, AE1 is preferably 40.0 mass % or less, more preferably 38.0 mass % or less, and even more preferably 35.0 mass % or less in order to reduce heat generation.

[0071] The acetone extractable amount (AE) can be adjusted by changing the types or amounts of chemicals combined in a rubber composition. For example, the acetone extractable amount can be increased by increasing the oil content.

[0072] A hardness Hs of the rubber composition constituting the tread portion is preferably 40 or more, more preferably 50 or more, even more preferably 55 or more, and particularly preferably 60 or more from the viewpoint of the effects of the present invention. Furthermore, from the viewpoint of grip performance, it is preferably 100 or less, more preferably 90 or less, and even more preferably 80 or less.

[0073] The rubber hardness of the rubber composition can be adjusted by a conventional method in the tire industry. In particular, it can be adjusted by changing the types or amounts of chemicals (e.g., a rubber component, a filler, a resin component, sulfur, a vulcanization accelerator, a silane coupling agent, etc.) incorporated in the rubber composition. For example, the rubber hardness can be lowered by increasing the oil content, and conversely, it can be increased by decreasing the content. Therefore, one skilled in the art can adjust the rubber hardness appropriately.

[0074] The complex modulus at 30 °C of the rubber composition forming the tread portion (30 °CE* T ) is preferably 8.0 MPa or more, more preferably 10.0 MPa or more, even more preferably 15.0 MPa or more, and particularly preferably 19.0 MPa or more. In addition, 30 °CE* Tpreferably 45.0 MPa or less, more preferably 40.0 MPa or less, and even more preferably 38.0 MPa or less.

[0075] 30 °CE* and 70 °CE* can be appropriately adjusted depending on the types or compounding amounts of a rubber component, a filler, a plasticizer, a vulcanizing agent, a vulcanization accelerator, and the like described below. For example, as the total amount of styrene in the rubber component increases, the value of E* tends to increase. Furthermore, as the compounding amount of a filler (particularly carbon black) or a resin component increases, the value of E* tends to increase.

[0076] The total amount of styrene in the rubber component of the rubber composition constituting the tread portion is preferably 8.0 mass% or more, more preferably 15.0 mass% or more, and even more preferably 30.0 mass% or more. An upper limit of the total amount of styrene is not particularly limited, but may be, for example, 60.0 mass% or less, 50.0 mass% or less, or the like. < <seitenwand>>

[0077] In Fig. 1, the sidewall 2 extends from the end of the tread portion 1 substantially inwardly in the tire radial direction. An outer part of the sidewall 2 in the tire radial direction is joined to the tread portion 1. The outer end of the sidewall 2 in the tire radial direction may end on the inner side of the tread portion 1 in the tire radial direction, as shown in Fig. 1, or may end with respect to the tread portion 1b on the outside in the tire radial direction so as to cover the tread portion 1.

[0078] An inner part of the sidewall 2 in the tire radial direction is joined to the clinching portion 10. The inner end of the sidewall 2 in the tire radial direction may be exposed on the tire surface side or may not be exposed on the tire surface so as to enter an inner side of the clinching portion 10 in a tire width direction.

[0079] The sidewall 2 may be formed of two or more rubber layers that are not partially or completely exposed on the tire surface. When the sidewall 2 comprises two or more rubber layers, any of the physical properties, such as an AE amount, a rubber hardness, and the like, of the rubber composition constituting the sidewall may be satisfied in any of the rubber layers. Moreover, the layer that is not partially exposed may be a rubber layer colored in a color other than black from the viewpoint of aesthetic appearance. Furthermore, the sidewall 2 may be provided with periodic concavities and convexities from the viewpoint of aesthetic appearance.As the concavities and convexities, the side wall 2 may include various types, such as ornaments of letters, patterns, and the like, as well as serrations caused by joints of internal elements designed to reduce the visibility of the concavities and convexities, minute protrusions designed to visually increase the degree of darkness by providing concavities and convexities that are finer than the serrations, and the like. Furthermore, an electronic tag or the like that enables communication with the outside world may be embedded within the side wall 2.

[0080] The acetone-extractable amount AE2 of the rubber composition forming the sidewall is larger than the acetone-extractable amount AE3 of the rubber composition forming the strip apex, and in particular, from the viewpoint of the effects of the present invention, it is preferably 5.0 mass% or more, more preferably 6.0 mass% or more, even more preferably 7.0 mass% or more, and particularly preferably 8.0 mass% or more. Furthermore, AE2 is smaller than AE1, and in particular, AE2 is preferably 12.0 mass% or less, more preferably 10.0 mass% or less, and even more preferably 9.0 mass% or less.

[0081] The complex elastic modulus at 70 °C of the rubber composition forming the sidewall (70 °CE* S ) is preferably 2.0 MPa or more, more preferably 3.0 MPa or more, and even more preferably 4.0 MPa or more. Furthermore, 70 °CE* S preferably 12.0 MPa or less, more preferably 10.0 MPa or less, and even more preferably 8.0 MPa or less. < <streifenapex>>

[0082] The tire according to the present embodiment includes a stripe apex 5 formed of the rubber composition on the inner side of the sidewall in the tire axial direction or on the inner side of the roll-back portion of the carcass in the tire axial direction.

[0083] In Fig. 1, the strip apex 5 is not completely covered by the roll-back portion of the carcass 4, and its upper portion is in contact with the sidewall, but this is not limited to such an aspect, and the strip apex 5 may be completely covered by the carcass 4 as long as it is present on the inner side of the roll-back portion of the carcass in the tire axial direction. It is preferable that the strip apex 5 is present on the inner side of the sidewall in the tire axial direction, and it is further preferable that a portion of the strip apex 5 is in contact with the sidewall. By configuring the upper portion of the strip apex 5 so as to be Fig. 1, is in contact with the sidewall, strain can be transferred in stages from the rim to the sidewall, which is believed to further improve wet grip performance during turning.

[0084] The acetone-extractable amount AE3 of the rubber composition forming the strip apex is preferably 3.0 mass% or more, more preferably 4.0 mass% or more, and even more preferably 5.0 mass% or more, from the viewpoint of the effects of the present invention. Furthermore, AE3 is smaller than AE2, and in particular, AE3 is preferably 9.0 mass% or less, more preferably 8.0 mass% or less, and even more preferably 7.0 mass% or less.

[0085] A complex elastic modulus at 70 °C of the rubber composition forming the strip apex (70 °CE* A ) is preferably 3.0 MPa or more, more preferably 5.0 MPa or more, and even more preferably 8.0 MPa or more. In addition, 70 °CE* A preferably 15.0 MPa or less, more preferably 12.0 MPa or less, and even more preferably 10.0 MPa or less. 70 °CE* A is preferably greater than 70 °CE* S . If a sample is measured at 70 °CE* A cannot be produced by cutting from the tire, an unvulcanized rubber composition for the strip apex obtained by kneading is vulcanized into a test rubber sheet, and a sample cut from the rubber sheet may be the sample for measurement. <<Laufflächenprofil> >

[0086] Fig. 2 shows a tread pattern of a tire according to an embodiment of the present invention, but the tread pattern of the tire according to the present embodiment is not limited to the tread pattern shown in Fig. 2 shown limited. In Fig. 2 CL is a tire equator.

[0087] The elevation ratio L is 0.60 or more, preferably 0.65 or more, more preferably 0.70 or more, even more preferably 0.80 or more, and particularly preferably 0.84 or more, from the viewpoints of improving the ground contact property of the tread portion on the road surface and improving grip performance during turning. Furthermore, an upper limit of the elevation ratio L is not particularly limited, but for a tire for a passenger car, it is usually 0.95 or less, and preferably 0.90 or less.

[0088] 30 °C* T × L is preferably less than 30, more preferably less than 25, even more preferably less than 20 and most preferably less than 17. In addition, 30 °CE* T × L preferably greater than 4, more preferably greater than 6 and even more preferably greater than 8.

[0089] AE1 × L is preferably 14.0 or more, and more preferably 16.5 or more. Furthermore, AE1 × L is preferably 30.0 or less.

[0090] AE2 × L is preferably greater than 4.0, more preferably greater than 4.5, and even more preferably greater than 5.0. Furthermore, AE2 × L is preferably less than 11.0 and more preferably less than 10.0.

[0091] AE3 × L is preferably greater than 3.0, more preferably greater than 3.5, even more preferably greater than 4.0, and most preferably greater than 4.5. Furthermore, AE3 × L is preferably less than 10.0, more preferably less than 8.0, and even more preferably less than 7.0.

[0092] 70 °C* S × L is preferably greater than 2.5, more preferably greater than 3.5, even more preferably greater than 4.0, and most preferably greater than 5.0. In addition, 70 °CE* S × L is preferably less than 15.0, more preferably less than 12.0, and even more preferably less than 10.0.

[0093] A product (Hs × L) of the hardness of the rubber composition constituting the tread portion and L is preferably less than 70, more preferably less than 65, even more preferably less than 60, even more preferably less than 55, and particularly preferably less than 49. Moreover, Hs × L is preferably greater than 10, more preferably greater than 15, and even more preferably greater than 20.

[0094] In Fig. 2, the tread section has an outer tread end To and an inner tread end Ti. The outer tread end To is located on an outer side of the vehicle when mounted on a vehicle (on the right side in Fig. 2). The inner tread end Ti is located on the inside of the vehicle when mounted on the vehicle (on the left side in Fig. 2). Each of the tread ends To and Ti is located in a ground contact position on the outermost side in a tire width direction W (the left-right direction in Fig. 2, hereinafter referred to simply as a width direction W) when a standardized load is applied to a tire in a standardized state and the tire contacts the ground with a flat surface at a camber angle of 0°.

[0095] In Fig. 2, the tread pattern of the tread portion is formed in an asymmetric shape with respect to the tire equator.

[0096] In the centered tire equator CL, when Lo represents a land contact area ratio of an outer tread portion (o) constituting an end side outside a vehicle, and Li represents a land contact area ratio of an inner tread portion (i) constituting the end side outside the vehicle, an absolute value of a difference (Lo-Li) between Lo and Li is preferably greater than 0, and more preferably greater than 0.05. Moreover, the absolute value of Lo-Li is preferably less than 0.2.

[0097] In Fig. 1, the tread portion has a plurality of circumferential grooves 15 which extend continuously in a circumferential direction C. In Fig. 2, three circumferential grooves 20, 21, 22 are provided. However, the number of circumferential grooves is not particularly limited and may be, for example, 2 to 5. Moreover, in the present embodiment, although the circumferential grooves 20, 21, 22 extend linearly along the circumferential direction C, they are not limited to such an aspect and may, for example, extend in a wavy shape, a sinusoidal shape, a zigzag shape, or the like along the circumferential direction C.

[0098] In Fig. 2, narrow circumferential grooves 25 are formed on land portions 23 of the inner tread portion and the outer tread portion. The narrow circumferential grooves contribute to improving drainage performance, which therefore contributes to improving the wet grip performance of the tire.

[0099] In addition, Fig. 2, the tread portion has a plurality of side grooves 24 extending in the tire width direction, and narrow side grooves 26 are further formed on the land portions 23 of the inner tread portion and the outer tread portion. In addition, in Fig. 2 the tread portion is also provided with inclined grooves 27 extending in a curved manner. [Rubber composition]

[0100] The rubber compositions constituting the tread portion, the sidewall, and the strip apex according to the present embodiments (hereinafter referred to as the rubber composition according to the present embodiment) can be produced by using raw materials described below according to a required acetone extractable amount or the like. A detailed description follows. <kautschukkomponente>

[0101] The rubber composition according to the present invention comprises a rubber component. As the rubber component, any of those conventionally used in the tire industry can be suitably used, examples of which include, for example, an isoprene-based rubber containing a natural rubber (NR) and a polyisoprene rubber (IR), a diene-based rubber such as a styrene-butadiene rubber (SBR), a butadiene rubber (BR), a styrene-isoprene rubber (SIR), a styrene-isoprene-butadiene rubber (SIBR), a chloroprene rubber (CR), an acrylonitrile-butadiene rubber (NBR) and the like, and a butyl-based rubber such as a halogenated butyl rubber and the like containing a butyl rubber (IIR), a brominated butyl rubber (Br-IIR), a chlorinated Butyl rubber (Cl-IIR) and a fluorinated butyl rubber (F-IIR).These rubber components can be used alone, or two or more of them can be used in combination.

[0102] The rubber composition forming the tread portion preferably comprises an SBR. The rubber composition forming the tread portion may comprise a rubber component consisting of an SBR.

[0103] The rubber composition forming the sidewall preferably comprises one or more rubber components selected from the group consisting of an isoprene-based rubber, an SBR, and a BR, more preferably comprises any one of an isoprene-based rubber and a BR, and even more preferably comprises an isoprene-based rubber and a BR. The rubber composition forming the sidewall may comprise a rubber component consisting of an isoprene-based rubber and a BR.

[0104] The rubber composition forming the strip apex preferably comprises an isoprene-based rubber. The rubber composition forming the strip apex may comprise a rubber component consisting of an isoprene-based rubber. (SBR)

[0105] An SBR is not particularly limited; examples thereof include a solution-polymerized SBR (S-SBR), an emulsion-polymerized SBR (E-SBR), modified SBRs (a modified S-SBR, a modified E-SBR) thereof, and the like. Examples of the modified SBR include an SBR modified at its terminal and / or main chain, a modified SBR coupled with tin, a silicon compound, etc. (a modified SBR of condensate or having a branched structure, etc.), and the like. Furthermore, hydrogenated SBRs (hydrogenated SBRs) and the like can also be used. These SBRs can be used alone, or two or more of them can be used in combination.

[0106] As an SBR, an oil-extended SBR or a non-oil-extended SBR can be used. In the present specification, the SBRs used can be those commercially available from JSR Corporation, Sumitomo Chemical Co., Ltd., UBE Corporation, Asahi Kasei Corporation, ZS Elastomer Co., Ltd., ARLANXEO, etc.

[0107] A styrene content of an SBR is preferably greater than 20 mass%, more preferably greater than 30 mass%, and even more preferably greater than 35 mass% from the viewpoint of cornering grip performance. On the other hand, the styrene content of the SBR is preferably less than 70 mass%, more preferably less than 60 mass%, and even more preferably less than 50 mass%. When the styrene content of the SBR exceeds 70 mass%, styrene groups become adjacent to each other, a polymer becomes too hard, and crosslinking is likely to become uneven, which may deteriorate blowing performance during high-temperature driving and increase temperature dependence. A change in performance with respect to a temperature change becomes large, resulting in a tendency that stable grip performance during driving cannot be satisfactorily obtained. Furthermore, in the present specification, the styrene content of the SBR is measured by the measurement method described above.

[0108] The vinyl content of an SBR is preferably more than 20 mol%, more preferably more than 30 mol%, and even more preferably more than 35 mol%. Furthermore, the vinyl content of the SBR is preferably less than 70 mol%, more preferably less than 65 mol%, and even more preferably less than 60 mol%. Furthermore, in the present specification, the vinyl content of the SBR is measured by the measurement method described above.

[0109] A content of an SBR in the rubber component of the rubber composition constituting the tread portion is preferably more than 15 mass %, more preferably more than 20 mass %, even more preferably more than 50 mass %, even more preferably more than 80 mass %, and particularly preferably more than 90 mass % from the viewpoint of the effects of the present invention. The content of the SBR in the rubber component of the rubber composition constituting the tread portion may be 100 mass %. A content of an SBR in the rubber component of any of the rubber compositions constituting the sidewall and the strip apex is not particularly limited, and the rubber composition may not include an SBR. (Isoprene-based rubber)

[0110] As an isoprene-based rubber, for example, those commonly used in the tire industry can be used, such as isoprene rubber (IR), natural rubber, and the like. Examples of natural rubber include unmodified natural rubber (NR) and modified natural rubber, such as epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), deproteinized natural rubber (DPNR), ultra-pure natural rubber, grafted natural rubber, and the like. These isoprene-based rubbers can be used alone, or two or more of them can be used in combination.

[0111] The NR is not particularly limited, and those commonly used in the tire industry can be used, examples of which include SIR20, RSS#3, TSR20 and the like.

[0112] From the viewpoint of the effects of the present invention, the content of an isoprene-based rubber in the rubber component of the rubber composition forming the strip apex is preferably more than 50 mass%, more preferably more than 80 mass%, and even more preferably more than 90 mass%. The content of the isoprene-based rubber in the rubber component of the rubber composition forming the strip apex may be 100 mass%.

[0113] A content of an isoprene-based rubber in the rubber component of the rubber composition constituting the sidewall is preferably 50 mass% or more, more preferably 60 mass% or more, and even more preferably 70 mass% or more, from the viewpoint of the effects of the present invention. Furthermore, from the viewpoint of bonding other rubber components, the content is preferably 90 mass% or less, more preferably 85 mass% or less, and even more preferably 80 mass% or less.

[0114] A content of an isoprene-based rubber in the rubber component of the rubber composition constituting the tread portion is not particularly limited, and the rubber composition may not include an isoprene-based rubber. (BR)

[0115] A BR is not particularly limited, and those commonly used in the tire industry can be used, such as a BR with a cis content of less than 50 mol% (a low-cis BR), a BR with a cis content of 90 mol% or more (a high-cis BR), a rare earth-based butadiene rubber synthesized using a rare earth element-based catalyst (a rare earth-based BR), a BR containing a syndiotactic polybutadiene crystal (a SPB-containing BR), a modified BR (a high-cis modified BR, a low-cis modified BR), and the like. These BRs can be used alone, or two or more of them can be used in combination.

[0116] As the cis-rich BR, for example, those commercially available from Zeon Corporation, UBE Corporation, JSR Corporation, etc. can be used. When the cis-rich BR is combined, low-temperature properties and abrasion resistance can be improved. The cis content of the cis-rich BR is preferably more than 95 mol%, more preferably more than 96 mol%, and even more preferably more than 97 mol%. In addition, the cis content of the BR is measured by the measurement method described above.

[0117] The rare earth-based BR includes those synthesized using a rare earth element-based catalyst and having a vinyl content of preferably less than 1.8 mol%, more preferably less than 1.6 mol%, and even more preferably 1.5 mol% or less, and a cis content of preferably more than 95 mol%, more preferably more than 96 mol%, and even more preferably 97 mol% or more. For the rare earth-based BR, for example, those commercially available from LANXESS, etc., can be used.

[0118] Examples of SPB-containing BR include those in which a 1,2-syndiotactic polybutadiene crystal is chemically bonded and dispersed with BR, but not those in which the crystal is simply dispersed in the BR. As such SPB-containing BR, those commercially available from UBE Corporation, etc., can be used.

[0119] Examples of the modified BR include a BR modified with a functional group or the like similar to those described for the SBR, and a modified butadiene rubber (a modified BR) modified at its terminal and / or main chain with a functional group containing at least one element selected from the group consisting of silicon, nitrogen, and oxygen can be suitably used.

[0120] Examples of other modified BRs include those obtained by adding a tin compound after polymerizing 1,3-butadiene with a lithium initiator, the end of which is further bonded by a tin-carbon bond (tin-modified BR), and the like. Furthermore, the modified BR can be either non-hydrogenated or hydrogenated.

[0121] A content of a BR in the rubber component of the rubber composition forming the sidewall is preferably 10 mass% or more, more preferably 15 mass% or more, and even more preferably 20 mass% or more. Furthermore, the content is preferably 50 mass% or less, more preferably 40 mass% or less, and even more preferably 30 mass% or less.

[0122] A content of a BR in the rubber component of any of the rubber compositions constituting the tread portion and the stripe apex is not particularly limited, and the rubber composition may not comprise a BR. (Other rubber components)

[0123] The rubber component may include rubber components other than diene-based rubbers (non-diene-based rubbers) as long as they do not impair the effects of the present invention. As the non-diene-based rubbers, rubber components commonly used in the tire industry can be used. Examples thereof include, for example, a butyl-based rubber, an ethylene-propylene rubber, a polynorbornene rubber, a silicone rubber, a polyethylene chloride rubber, a fluororubber (FKM), an acrylic rubber (ACM), a hydrin rubber, and the like. These other rubber components may be used alone, or two or more of them may be used in combination. Furthermore, the rubber component may or may not include a known thermoplastic elastomer in addition to the rubber components described above. (Rubber component synthesized from recycled / biomass-derived raw material)

[0124] A material (monomer) of a synthetic rubber such as an SBR, a BR, and the like may be one derived from underground resources such as petroleum, natural gas, and the like, or one recycled from a rubber product such as a tire and the like, or a non-rubber product such as polystyrene and the like. A monomer obtained by recycling (a recycled monomer) is not particularly limited; examples thereof include a recycled polyisoprene, a recycled butadiene, a recycled aromatic vinyl, and the like. Examples of the butadiene include 1,2-butadiene, 1,3-butadiene, and the like. The above-described aromatic vinyl is not particularly limited; examples thereof include styrene and the like.Among them, a recycled polyisoprene (a recycled polyisoprene), a recycled butadiene (a recycled butadiene) and / or a recycled styrene (a recycled styrene) are preferably used as a raw material.

[0125] A method of producing a recycled monomer is not particularly limited, examples of which include, for example, a method of synthesizing a monomer from a recycled naphtha obtained by decomposing a rubber product such as a tire and the like. Furthermore, a method of producing a recycled naphtha is not particularly limited, and a recycled naphtha can be obtained, for example, by decomposing a rubber product such as a tire and the like under high temperature and high pressure, by decomposing it by microwaves, or by extruding it after mechanically pulverizing it.

[0126] Furthermore, a raw material (monomer) of a synthetic rubber such as an IR, an SBR, a BR, and the like may be a raw material derived from biomass. In the present specification, biomass refers to a material derived from natural sources such as plants and the like. Biomass is not particularly limited; examples include, for example, agricultural, forestry, and fishery products, sugar, wood waste, a plant residue after capture of a useful component, a plant-derived ethanol, a biomass naphtha, and the like.

[0127] The biomass-derived monomer (biomass monomer) is not particularly limited, and examples include biomass-derived butadiene, biomass-derived aromatic vinyl, and the like. Examples of the butadiene include 1,2-butadiene, 1,3-butadiene, and the like. The above-described aromatic vinyl is not particularly limited, and examples include styrene and the like. Furthermore, a method of producing a biomass monomer is not particularly limited, and examples include, for example, one by biological and / or chemical and / or physical conversion of animals and plants, and the like.Microbial fermentation is representative of biological conversion, and examples of chemical and / or physical conversion include one due to a catalyst, one due to high heat, one due to high pressure, one due to an electromagnetic wave, one due to a critical fluid, and combinations thereof.

[0128] A polymer synthesized from a biomass monomer component (biomass polymer) is not particularly limited; examples include a polybutadiene rubber synthesized from biomass-derived butadiene, an aromatic-vinyl-butadiene copolymer synthesized from biomass-derived butadiene and / or biomass-derived aromatic vinyl, and the like. Examples of the aromatic-vinyl-butadiene copolymer include, for example, a styrene-butadiene rubber synthesized from biomass-derived butadiene and / or biomass-derived styrene, and the like.

[0129] Whether a polymer raw material is derived from biomass can be determined by pMC (percent modern carbon) measured according to ASTM D6866-10.

[0130] Here pMC is a ratio of 14 C concentration of a sample to 14 C concentration of a modern standard reference carbon (modern standard reference) and a value used as an index indicating a compound's biomass ratio. The meaning of this value is mentioned below.

[0131] In 1 mole of carbon atoms (6.02 × 10 23 pieces) are about 6.02 × 10 11 14 C, which are about one trillionth the number of normal carbon atoms. A half-life of 14 C is 5730 years, and 14 C decreases regularly. Thus, for fossil fuels such as coal, petroleum, natural gas and the like, where it is assumed that 226,000 years or more have passed since carbon dioxide in the atmosphere was absorbed by plants to fix it, all 14 C elements that were present at the beginning of fixation. Therefore, fossil fuels such as coal, petroleum, natural gas and the like do not contain any 14 C element. Therefore, the chemical substances produced using these fossil fuels as raw materials also do not contain 14 C element.

[0132] on the other hand 14 C is constantly generated by cosmic rays that cause nuclear reactions in the atmosphere. Thus, decreases in 14 C due to radioactive decay and production of 14 C due to nuclear reactions and the amount of 14 C in the Earth’s atmospheric environment. Therefore, the 14 C concentration of substances derived from biomass resources circulating in the current environment, a value of about 1 × 10 -12 Mole% based on total carbon atoms, as described above. Accordingly, by using the difference between these values, a biomass ratio in a particular compound can be calculated.

[0133] This 14 C is generally measured as follows. Using accelerator mass spectrometry based on a tandem accelerator, a 13 C concentration ( 13 C / 12 C) and a 14 C concentration ( 14 C / 12 C) is measured. The measurements are 14 C concentration in a circulating carbon in nature from 1950 as the modern standard reference for the 14 C concentration is used. An oxalic acid standard body provided by the National Institute of Standards and Technology (NIST) is used as a specific reference material. A specific radioactivity of carbon in this oxalic acid (radioactivity intensity of 14 C per gram of carbon) is sorted for each carbon isotope, 13 C is corrected to a constant value, and a value corrected for attenuation from 1950 to the measurement date is used as a standard 14 C concentration value (100%) is used. The ratio of this value to an actually measured value for a sample is called a pMC value.

[0134] Thus, when a rubber is produced from a material derived from 100% biomass, the 14 C concentration has a value of approximately 110 pMC (currently it often does not reach 100 under normal conditions), since it often does not reach 100 under normal conditions, although there are regional differences and the like. On the other hand, it shows that if this 14 C concentration measured for a chemical derived from a fossil fuel, such as petroleum and the like, is approximately 0 pMC (e.g., 0.3 pMC). This value corresponds to a biomass ratio of 0%, as mentioned above.

[0135] Due to the above, it is suitable in terms of environmental protection to use a material such as a rubber having a high pMC value and the like, that is, a material such as a rubber having a high biomass ratio and the like for a rubber composition. [Filler]

[0136] The rubber composition according to the present embodiment preferably comprises silica and / or carbon black as a filler. The filler may be a filler consisting of carbon black and silica.

[0137] The rubber composition forming the tread portion preferably comprises silica or carbon black as a filler. Each of the rubber compositions forming the sidewall and strip apex preferably comprises carbon black as a filler. <siliciumdioxid>

[0138] Silica is not particularly limited, and those commonly used in the tire industry can be used, such as silica produced by a dry process (anhydrous silica), silica produced by a wet process (hydrous silica), and the like. A raw material of silica is not particularly limited and can be, for example, mineral-derived raw materials such as quartz and the like, biomaterial-derived raw materials such as rice husks and the like (e.g., silica made from a biomass material such as rice husks and the like), or silica recycled from a silica-containing product. Among them, hydrous silica produced by a wet process is preferable because it has many silanol groups.This silica can be used alone, or two or more of them can be used in combination.

[0139] Silica from a biomass material can be obtained, for example, by burning rice husks to obtain rice husk ash, extracting silicate from the rice husk ash using a sodium hydroxide solution, producing silica by reacting the silicate with sulfuric acid in the same manner as for a conventional wet silica, and filtering, washing with water, drying, and pulverizing precipitates of the silica.

[0140] As the silica recycled from a product containing silica, for example, silica recovered from an electronic component such as a semiconductor, a tire, a product containing silica such as a desiccant, a filter material such as diatomaceous earth, and the like can be used. Furthermore, a recovery method is not particularly limited; examples include pyrolysis, decomposition by electromagnetic waves, and the like. Among them, silica recovered from an electronic component such as a semiconductor, etc., or from a tire is preferable.

[0141] When silicon dioxide crystallizes, it is insoluble in water, and silicic acid, a component of it, cannot be used. By controlling the firing temperature and firing time, crystallization of silicon dioxide in rice husk ash can be suppressed (JP 2009-2594 A, Akita Prefectural University Web Journal B / 2019, vol. 6, pp. 216-222, etc.). Amorphous silicon dioxide extracted from rice husks can be used, such as those commercially available from Wilmar, etc.

[0142] A specific nitrogen adsorption surface (N2SA) of silica is preferably larger than 110 m from the viewpoint of reinforcement property 2 / g, more preferably greater than 130 m 2 / g, even more preferably greater than 150 m 2 / g and particularly preferably greater than 170 m 2 / g. In addition, from the point of view of heat generation and processability, it is preferably less than 220 m 2 / g, more preferably less than 200 m 2 / g and even more preferably less than 180 m 2 / g. In addition, the N2SA of silicon dioxide is measured using the measurement method described above.

[0143] An average primary particle size of silica is preferably larger than 10 nm, more preferably larger than 12 nm, and even more preferably larger than 14 nm from the viewpoint of the effects of the present invention. Furthermore, the average primary particle size is preferably smaller than 20 nm, more preferably smaller than 19 nm, and even more preferably smaller than 18 nm. In addition, the average primary particle size of silica is measured by the measuring method described above.

[0144] A silica content based on 100 parts by mass of the rubber component when combined in the rubber composition forming the tread portion is preferably greater than 90 parts by mass, more preferably greater than 95 parts by mass or more, and even more preferably greater than 100 parts by mass. Furthermore, the silica content based on 100 parts by mass of the rubber component in this case is preferably less than 200 parts by mass, more preferably less than 180 parts by mass, and even more preferably less than 150 parts by mass. However, the rubber composition forming the tread portion may not include silica.

[0145] A content of silica in each of the rubber compositions constituting the sidewall and the strip apex is not particularly limited, and the rubber composition may not comprise silica. <silankupplungsmittel>

[0146] Silica is preferably used in combination with a silane coupling agent. Examples of the silane coupling agent include, for example, sulfide-based silane coupling agents such as bis(3-triethoxysilylpropyl)disulfide, bis(3-triethoxysilylpropyl)tetrasulfide, and the like; mercapto-based silane coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, and the like; vinyl-based silane coupling agents such as vinyltriethoxysilane, vinyltrimethoxysilane, and the like; amino-based silane coupling agents such as 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, and the like. Glycidoxy-based silane coupling agents such as γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane and the like;Nitro-based silane coupling agents such as 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and the like; and chlorine-based silane coupling agents such as 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, and the like, but are not particularly limited thereto. Among them, sulfide-based silane coupling agents and / or mercapto-based silane coupling agents are preferably used. As the silane coupling agent, for example, those commercially available from Evonik Industries AG, Momentive Performance Materials, etc. can be used. These silane coupling agents can be used alone, or two or more of them can be used in combination.

[0147] A content of a silane coupling agent based on 100 parts by mass of the rubber component (a total amount of plural silane coupling agents when used in combination) is preferably greater than 5.0 parts by mass, more preferably greater than 8.0 parts by mass, and even more preferably greater than 10.0 parts by mass from the viewpoint of enhancing silica dispersibility. Furthermore, from the viewpoint of preventing deterioration of abrasion resistance, it is preferably less than 25 parts by mass, more preferably less than 20 parts by mass, and even more preferably less than 15 parts by mass. <Ruß>

[0148] Carbon black is not particularly limited, and those commonly used in the tire industry can be used, such as GPF, FEF, HAF, ISAF, SAF and the like, and in particular, N110, N115, N120, N125, N134, N135, N219, N220, N231, N234, N293, N299, N326, N330, N339, N343, N347, N351, N356, N358, N375, N539, N550, N582, N630, N642, N650, N660, N683, N754, N762, N765, N772, N774, N787, N907, N908, N990, N991 and the like can be used. can be suitably used, and internally synthesized products and the like can also be suitably used. A raw material of carbon black may be a biomass material such as lignin, a vegetable oil, and the like, or may be a pyrolysis oil obtained by pyrolyzing a waste tire.In addition, a method of producing carbon black may be one by combustion, such as a furnace method, etc., one by hydrothermal carbonization (HTC), or one by pyrolysis of methane, such as a thermal carbon black method, etc. As commercially available products, products from Asahi Carbon Co., Ltd., Cabot Japan KK, Tokai Carbon Co., Ltd., Mitsubishi Chemical Corporation, Lion Corporation, NIPPON STEEL Carbon Co. Ltd., Columbia Chemical Corporation, etc. can be used. They can be used alone, or two or more of them can be used in combination.

[0149] Furthermore, in addition to the carbon black described above, from the viewpoint of environmental performance, carbon black from a biomass material such as lignin and the like, or a reclaimed carbon black obtained by pyrolyzing and refining a product containing carbon black such as a tire and the like can be used as the carbon black.

[0150] A "recovered carbon black" in the present specification refers to a carbon black obtained by pulverizing a product such as a used tire comprising carbon black and the like and burning the pulverized product, in which, when the product is subjected to oxidative combustion by heating in the air using a thermal gravity measurement method according to JIS K 6226-2:2003, a mass ratio of ash (ash content), which is a component that does not burn, is 13 mass% or more. That is, a mass ratio (amount of carbon) of a weight loss content due to oxidative combustion of the recovered carbon black is 87 mass% or less. The recovered carbon black can be expressed by rCB.

[0151] The recovered carbon black can be obtained from a pyrolysis process of a used pneumatic tire. For example, EP3427975 A, with reference to "Rubber Chemistry and Technology", Vol. 85, No. 3, pages 408 to 449 (2012), particularly pages 438, 440, and 442, describes that the recovered carbon black can be obtained by pyrolysis of an organic material at 550 to 800°C in the absence of oxygen or by vacuum pyrolysis at a relatively low temperature (

[0027] ). As mentioned in

[0004] of JP 6856781 B (A comparison of surface morphology and chemistry of pyrolytic carbon blacks with commercial carbon blacks, Powder Technology 160 (2005) 190-193), such carbon black obtained by the pyrolysis process usually lacks a functional group on its surface.

[0152] The recovered carbon black may lack a functional group on its surface, or it may be treated so that its surface includes a functional group. The treatment performed so that the surface of the recovered carbon black includes a functional group can be implemented by a conventional method. For example, in EP3173251A, carbon black including a hydroxyl and / or carboxyl group on its surface is obtained by treating carbon black obtained from a pyrolysis process with potassium permanganate under an acidic condition. Furthermore, in JP6856781B, carbon black whose surface is activated is obtained by treating carbon black obtained from a pyrolysis process with an amino acid compound including at least one thiol group or disulfide group. The recovered carbon black according to the present embodiment also includes carbon black whose surface has been treated to include a functional group.As the recovered carbon black, those commercially available from Strebl Green Carbon Pte Ltd., LDC Co., Ltd. etc. can be used.

[0153] An average primary particle size of carbon black in the rubber composition constituting the tread portion is preferably 30 nm or less, more preferably 25 nm or less, even more preferably 20 nm or less, and particularly preferably 18 nm or less. Furthermore, the average primary particle size is preferably greater than 8 nm, more preferably greater than 10 nm, even more preferably greater than 12 nm, and particularly preferably greater than 14 nm. Furthermore, the average primary particle size of carbon black is measured by the measurement method described above.

[0154] An average primary particle size of carbon black in each of the rubber compositions constituting the sidewall and the stripe apex is preferably greater than 50 nm, more preferably greater than 60 nm, even more preferably greater than 70 nm, and particularly preferably greater than 80 nm. Moreover, the average primary particle size is preferably 120 nm or smaller, more preferably 110 nm or smaller, and even more preferably 100 nm or smaller.

[0155] A specific nitrogen adsorption surface area (N2SA) of carbon black in the rubber composition constituting the tread portion is preferably 50 m from the viewpoints of reinforcing property and adhesion performance 2 / g or more, more preferably 70 m 2 / g or more, more preferably 100 m 2 / g or more and particularly preferably 120 m 2 / g or more. In addition, from the point of view of dispersibility, it is preferably 250 m 2 / g or less and more preferably 220 m 2 / g or less. In addition, the N2SA of soot is measured using the measurement method described above.

[0156] A specific nitrogen adsorption surface area (N2SA) of carbon black in each of the rubber compositions constituting the sidewall and the strip apex is preferably 20 m from the viewpoints of reinforcing property and adhesion performance 2 / g or more, more preferably 30 m 2 / g or more and even more preferably 40 m 2 / g or more. In addition, from the point of view of dispersibility, it is preferably 80 m 2 / g or less, more preferably 60 m 2 / g or less and more preferably 50 m 2 / g or less.

[0157] A content of carbon black based on 100 parts by mass of the rubber component when combined in the rubber composition constituting the tread portion is preferably greater than 5 parts by mass, more preferably greater than 60 parts by mass, even more preferably greater than 80 parts by mass, even more preferably greater than 100 parts by mass, and particularly preferably greater than 110 parts by mass. Moreover, the content of carbon black based on 100 parts by mass of the rubber component in this case is preferably less than 200 parts by mass, more preferably less than 180 parts by mass, and even more preferably less than 150 parts by mass. However, when the rubber composition constituting the tread portion comprises silica as a filler, the content of carbon black based on 100 parts by mass of the rubber component is preferably less than 30 parts by mass, and more preferably less than 20 parts by mass.

[0158] The carbon black content based on 100 parts by mass of the rubber component in each of the rubber compositions constituting the sidewall and the strip apex is preferably greater than 30 parts by mass, more preferably greater than 40 parts by mass, and even more preferably greater than 50 parts by mass. Furthermore, the content is preferably less than 100 parts by mass, more preferably less than 80 parts by mass, and even more preferably less than 75 parts by mass. <Andere Füllstoffe>

[0159] The filler may contain other fillers besides silica and carbon black. Other fillers are not particularly limited, and those conventionally and commonly used in the tire industry, such as aluminum hydroxide, calcium carbonate, alumina, clay, talc, and the like, may be combined.

[0160] A total content of fillers based on 100 parts by mass of the rubber component in the rubber composition constituting the tread portion is preferably greater than 80 parts by mass, more preferably greater than 90 parts by mass, and even more preferably greater than 100 parts by mass.

[0161] In one embodiment of the rubber composition constituting the tread portion, the filler may be one consisting of carbon black, and the tread portion of this embodiment is suitably used for, for example, a racing tire.

[0162] In one embodiment of the rubber composition constituting the tread portion, the filler may be one comprising more than 100 parts by mass of silica based on 100 parts by mass of the rubber component, and the tread portion of this embodiment is suitably used for, for example, a tire for a passenger car. [Other connecting devices]

[0163] The rubber composition according to the present embodiment may suitably comprise, in addition to rubber components and fillers, coupling agents conventionally and usually used in the tire industry, for example, a plasticizer, a vulcanized rubber particle, processing aids, wax, stearic acid, zinc oxide, an antioxidant, a crosslinking agent, a vulcanization accelerator, and the like. <plastifizierungsmittel>

[0164] The plasticizer is a material that imparts plasticity to the rubber component and has a concept that includes both a plasticizer that is liquid in a liquid state at 25°C and a plasticizer that is solid at 25°C. Examples of the plasticizer include a resin component, oil, a liquid polymer, an ester-based plasticizer, and the like. These plasticizers may be those derived from mineral resources such as petroleum, natural gas, and the like, or those derived from naphtha and recycled from a rubber product or a non-rubber product.In addition, low-molecular-weight hydrocarbon components obtained by pyrolyzing waste tires or products containing various components and performing extraction from the pyrolyzate can be used as plasticizers. These plasticizers can be used alone, or two or more of them can be used in combination. (resin component)

[0165] The rubber composition forming the tread portion and the rubber composition forming the sidewall may comprise a resin component in combination. The resin component that can be used in the present embodiment is not particularly limited, and any resin commonly used in the tire industry can be used. Examples thereof include, for example, a C9-based resin, a C5-based resin, a C5 / C9-based resin, a dicyclopentadiene-based resin, an aromatic vinyl-based resin, a coumarone-based resin, an indene-based resin, a terpene-based resin, a rosin-based resin, a phenol-based resin, and the like. These resin components can be used alone, or two or more of them can be used in combination. Each resin component can also be used alone, or two or more of them can be used in combination. <<Harz auf C9-Basis> >

[0166] A "C9-based resin" refers to a resin obtained by polymerizing C9 fractions, and may be a polymer obtained by polymerizing a C9 fraction alone or a copolymer obtained by copolymerizing a C9 fraction with other components. For example, a resin obtained by copolymerizing dicyclopentadiene (DCPD) with a C9 fraction is called a DCPD / C9 resin. Furthermore, the C9-based resin may be one obtained by hydrogenating or modifying it. Examples of the C9 fraction include, for example, a petroleum fraction having 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, coumarone, indene, methylindene, dicyclopentadiene, and the like. As the C9-based resin, for example, those commercially available from BASF, Zeon Corporation, ENEOS Corporation, etc. can be used. <<Harz auf C5-Basis> >

[0167] A "C5-based resin" refers to a resin obtained by polymerizing C5 fractions, and may be one obtained by hydrogenating or modifying them. Examples of C5 fractions other than dicyclopentadiene include, for example, a petroleum fraction having 4 to 5 carbon atoms, such as cyclopentadiene, isoprene, piperylene, 2-methyl-1-butene, 2-methyl-2-butene, 1-pentene, and the like. As the C5-based resin, for example, those commercially available from STRUKTOL, Zeon Corporation, ENEOS Corporation, etc. can be used. <<Harz auf C5 / C9-Basis> >

[0168] A "C5 / C9-based resin" refers to a resin obtained by copolymerizing the C5 fraction and the C9 fraction, and may be one obtained by hydrogenating or modifying them. As the C5 / C9-based petroleum resin, for example, those commercially available from Tosoh Corporation, Zibo Luhua Hongjin New Material Group Co., Ltd., etc., can be suitably used. <<Harz auf Dicyclopentadien-Basis> >

[0169] A "dicyclopentadiene-based resin" refers to a resin comprising cyclopentadiene (CPD) and / or dicyclopentadiene (DCPD) as a monomer component with the largest content, and may be one obtained by hydrogenating or modifying them. As the dicyclopentadiene-based resin, for example, a polymer obtained by polymerizing only dicyclopentadiene as a monomer, a copolymer obtained by copolymerizing dicyclopentadiene with the C9 fraction (DCPD / C9 resin), and the like are preferable. As the dicyclopentadiene-based resin, for example, those commercially available from Exxon Mobil Corporation, ENEOS Corporation, Zeon Corporation, Maruzen Petrochemical Co., Ltd., etc. can be used. <<Harz auf aromatischer Vinyl-Basis> >

[0170] An "aromatic vinyl-based resin" refers to a resin comprising an aromatic vinyl compound such as styrene, α-methylstyrene, vinyltoluene, p-chlorostyrene, and the like as a monomer component having the largest content, and may be one obtained by hydrogenating or modifying them. As the aromatic vinyl-based resin, a homopolymer of α-methylstyrene or styrene or a copolymer of α-methylstyrene and styrene is preferred, and a copolymer of α-methylstyrene and styrene is more preferred because it is economical, easy to process, and excellent in heat generation. As the aromatic vinyl-based resin, for example, those commercially available from Kraton Corporation, Eastman Chemical Company, Mitsui Chemicals, Inc., etc. can be used. <<Harz auf Cumaron-Basis> >

[0171] A "coumarone-based resin" refers to a resin comprising coumarone as a monomer component and may be one obtained by hydrogenating or modifying it. As the coumarone-based resin, for example, a coumarone resin which is a polymer comprising only coumarone as a monomer component, a coumarone-indene resin which is a copolymer comprising coumarone and indene as monomer components, a coumarone-indene-styrene resin which is a copolymer comprising coumarone, indene, and styrene as monomer components, and the like are preferable. As the coumarone-based resin, for example, those commercially available from Rutgers Chemicals, Nitto Chemical Co., Ltd., Mitsui Chemicals, Inc., etc. can be used. <<Harz auf Inden-Basis> >

[0172] An "indene-based resin" refers to a resin comprising indene as a monomer component and may be one obtained by hydrogenating or modifying it. As the indene-based resin, for example, a coumarone-indene resin, which is a copolymer comprising coumarone and indene as monomer components, a coumarone-indene-styrene resin, which is a copolymer comprising coumarone, indene, and styrene as monomer components, and the like are preferable. As the indene-based resin, for example, those commercially available from Rutgers Chemicals, Nitto Chemical Co., Ltd., Mitsui Chemicals, Inc., etc. can be used. <<Harz auf Terpen-Basis> >

[0173] A "terpene-based resin" refers to a resin comprising a terpene compound such as α-pinene, β-pinene, limonene, dipentene, and the like as a monomer component, and may be one obtained by hydrogenating or modifying it. As the terpene-based resin, for example, a polyterpene resin that is a polymer comprising only one or more of the terpene compounds as monomer components, an aromatic-modified terpene resin that is a copolymer comprising the terpene compound and an aromatic compound as monomer components, a terpene-phenolic resin that is a copolymer comprising the terpene compound and a phenol compound as monomer components, and the like are preferable. Examples of the aromatic compound used as a monomer component for the aromatic-modified terpene resin include, for example, styrene, α-methylstyrene, vinyltoluene, divinyltoluene, and the like.Examples of the phenol compound used as a monomer component for the terpene-phenol resin include, for example, phenol, bisphenol A, cresol, xylenol, and the like. As the terpene-based resin, for example, those commercially available from Yasuhara Chemical Co., Ltd., Arakawa Chemical Industries, Ltd., Nippon Terpene Chemicals, Inc., etc., can be used. <<Harz auf Kolophonium-Basis> >

[0174] A "rosin-based resin" refers to a resin comprising a rosin acid compound such as abietic acid, neoabietic acid, palustric acid, isopimaric acid, and the like, and may be one obtained by hydrogenating or modifying it. Examples of the rosin-based resin include, for example, a natural resin rosin and a rosin-modified resin obtained by modifying the natural resin rosin through hydrogenation, disproportionation, dimerization, esterification, etc., but are not particularly limited. As the rosin-based resin, for example, those commercially available from Harima Chemicals Group, Inc., Arakawa Chemical Industries, Ltd., IREC Co., Ltd., etc. can be used. <<Harz auf Phenol-Basis> >

[0175] A "phenol-based resin" refers to a resin comprising a phenolic compound such as phenol, cresol, and the like as a monomer component, and may be one obtained by hydrogenating or modifying it. Examples of the phenol-based resin include, but are not particularly limited to, a phenol-formaldehyde resin, an alkylphenol-formaldehyde resin, an alkylphenol-acetylene resin, an oil-modified phenol-formaldehyde resin, a terpene-phenol resin, and the like. As the phenol-based resin, for example, those commercially available from Sumitomo Bakelite Co., Ltd., DIC Corporation, ASAHI YUKIZAI CORPORATION, etc. can be used. < <erweichungspunkt>>

[0176] From the viewpoint of adhesion performance, a softening point of a resin component is preferably 60°C or higher, more preferably 70°C or higher, and even more preferably 80°C or higher. Furthermore, from the viewpoints of processability and improvement in dispersibility of a rubber component with a filler, it is preferably 150°C or lower, more preferably 140°C or lower, and even more preferably 130°C or lower. In addition, a softening point of resin is measured by the measurement method described above. < <gehalt>>

[0177] A content of a resin component when bonded based on 100 parts by mass of the rubber component is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, and particularly preferably 8 parts by mass or more from the viewpoint of adhesion performance. On the other hand, from the viewpoint of suppressing heat generation, the content is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 15 parts by mass or less. (Oil)

[0178] Examples of oil include, for example, mineral oil, vegetable oil, animal oil, and the like. Furthermore, from the perspective of environmental performance, those obtained by purifying waste oil after use in a rubber mixer or engine, or waste cooking oil used in a restaurant, can be used.

[0179] In the present specification, examples of the vegetable oil include, for example, linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice oil, tall oil, sesame oil, perilla oil, castor oil, tung 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, grape seed oil, Japan wax, and the like. Furthermore, examples of the vegetable oil also include a refined oil obtained by refining the above-described oil (edible oil, etc.).), a transesterified oil obtained by transesterifying the above-described oil, a hydrogenated oil obtained by hydrogenating the above-described oil, a thermally polymerized oil obtained by thermally polymerizing the above-described oil, an oxidized polymerized oil obtained by oxidizing the above-described oil, a used edible oil obtained by reclaiming what was used as an edible oil, etc., and the like. Furthermore, the vegetable oil may be liquid or solid at 25°C. These vegetable oils may be used alone, or two or more of them may be used in combination.

[0180] In the present specification, a mineral oil refers to oil derived from mineral resources such as petroleum, natural gas, and the like. Examples of the mineral oil include paraffinic oils (mineral oils), naphthenic oils, aromatic oils, and the like. Specific examples of the mineral oil include, for example, MES (Mild Extracted Solvate), DAE (Distillate Aromatic Extract), TDAE (Treated Distillate Aromatic Extract), TRAE (Treated Residual Aromatic Extract), RAE (Residual Aromatic Extract), and the like. In addition, as an environmental measure, an oil having a low content of a polycyclic aromatic compound (PCA) can also be used. Examples of the oil having a low content of a PCA content include MES, TDAE, a heavy naphthenic oil, and the like.

[0181] The vegetable oil according to the present embodiment preferably comprises acylglycerol, and more preferably comprises triacylglycerol. In addition, in the present specification, acylglycerol refers to a compound in which a hydroxy group of glycerol and a fatty acid are ester-bonded. Acylglycerol is not particularly limited and may be 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, or triacylglycerol. Furthermore, acylglycerol may be a monomer, a dimer, or a multimer that is a trimer or higher. Furthermore, acylglycerol that is a dimer or higher may be obtained by thermal polymerization, oxidative polymerization, or the like. Furthermore, acylglycerol may be liquid or solid at 25°C.

[0182] As a method of checking whether the rubber composition includes acylglycerol, the check may be carried out, but is not particularly limited to 1 H-NMR measurement. For example, a rubber composition containing triacylglycerol is immersed in heavy chloroform at 25 °C for 24 hours and then removed. 1 H NMR was subjected to room temperature, and signals near 5.26 ppm, near 4.28 ppm, and near 4.15 ppm were observed under a condition that a signal from tetramethylsilane (TMS) was set to 0.00 ppm. The signals are presumed to be derived from hydrogen atoms bonded to carbon atoms adjacent to oxygen atoms of an ester group. Furthermore, "near" in this paragraph is a range of ± 0.10 ppm.

[0183] The fatty acid described above is not particularly limited and can be an unsaturated fatty acid or a saturated fatty acid. Examples of the unsaturated fatty acid include a monounsaturated fatty acid such as oleic acid and the like, and a polyunsaturated fatty acid such as linoleic acid, linolenic acid, and the like. Furthermore, examples of the saturated fatty acid include butyric acid, lauric acid, and the like.

[0184] Among them, a fatty acid with few double bonds, that is, a saturated fatty acid or a monounsaturated fatty acid, is desirable as the fatty acid, and oleic acid is preferred. As a vegetable oil comprising such a fatty acid, for example, a vegetable oil comprising a saturated fatty acid or a monounsaturated fatty acid can be used, or a vegetable oil modified by interesterification or the like can be used. Furthermore, to produce a vegetable oil comprising such a fatty acid, a plant can be improved by selective breeding, gene recombination, or the like.

[0185] As the vegetable oil, for example, those commercially available from Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo KK, ENEOS Corporation, Olisoy, H&R Group, Hokoku Corporation, Fuji Kosan Co., Ltd., The Nisshin OilliO Group, Ltd., etc. can be used.

[0186] Examples of the animal oil include a fish oil, a beef tallow, an oleyl alcohol derived therefrom, and the like.

[0187] A content of oil when combined in the rubber composition constituting the tread portion based on 100 parts by mass of the rubber component is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 30 parts by mass or more, and particularly preferably 40 parts by mass or more from the viewpoint of the effects of the present invention. Furthermore, from the viewpoint of abrasion resistance, it is preferably 100 parts by mass or less, more preferably 90 parts by mass or less, and even more preferably 80 parts by mass or less.

[0188] The oil content when combined in each of the rubber compositions constituting the sidewall and the strip apex, based on 100 parts by mass of the rubber component, is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more. Furthermore, the content is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and even more preferably 10 parts by mass or less. (liquid rubber)

[0189] A liquid rubber is not particularly limited as long as it is a polymer in a liquid state at 25°C. Examples include, for example, a liquid butadiene rubber (a liquid BR), a liquid styrene-butadiene rubber (a liquid SBR), a liquid isoprene rubber (a liquid IR), a liquid styrene-isoprene rubber (a liquid SIR), a liquid farnesene rubber, and the like. These liquid rubbers can be used alone, or two or more of them can be used in combination.

[0190] A content of a liquid rubber when combined in the rubber composition constituting the tread portion is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more, based on 100 parts by mass of the rubber component. Furthermore, the content of the liquid rubber is not particularly limited, but may be, for example, 30 parts by mass or less, 20 parts by mass or less, or the like. (Ester-based plasticizer)

[0191] Examples of the ester-based plasticizer include, for example, dibutyl adipate (DBA), diisobutyl adipate (DIBA), dioctyl adipate (DOA), bis(2-ethylhexyl)azelate (DOZ), dibutyl sebacate (DBS), diisononyl adipate (DINA), diethyl phthalate (DEP), dioctyl phthalate (DOP), diundecyl phthalate (DUP), dibutyl phthalate (DBP), dioctyl sebacate (DOS), tributyl phosphate (TBP), trioctyl phosphate (TOP), triethyl phosphate (TEP), trimethyl phosphate (TMP), thymidine triphosphate (TTP), tricresyl phosphate (TCP), trixylenyl phosphate (TXP), and the like. The ester-based plasticizer can be used alone, or two or more of them can be used in combination. (Vulcanized rubber particle)

[0192] A vulcanized rubber particle is a particle made of vulcanized rubber, and in particular, rubber powder and the like specified in JIS K 6316:2017 can be used. From environmental and cost considerations, recycled rubber powder produced from a pulverized product of a scrap tire or the like is preferred. They can be used alone, or two or more of them can be used in combination.

[0193] The vulcanized rubber particle is not particularly limited and may be an unmodified vulcanized rubber particle or a modified vulcanized rubber particle.

[0194] Commercially available products of a vulcanized rubber particle include products from Lehigh Technologies, Muraoka Rubber Reclaiming Co., Ltd., etc. (processing aids)

[0195] Examples of processing aids include, for example, a fatty acid metal salt, a fatty acid amide, an amide ester, a silica surfactant, a mixture of a fatty acid metal salt and an amide ester, a mixture of a fatty acid metal salt and a fatty acid amide, and the like. These processing aids can be used alone, or two or more of them can be used in combination. For example, those commercially available from Schill+Seilacher GmbH, Performance Additives, etc. can be used as processing aids.

[0196] The content of the processing aid when combined, based on 100 parts by mass of the rubber component, is preferably greater than 0.5 parts by mass, more preferably greater than 1 part by mass, and even more preferably greater than 1.5 parts by mass from the viewpoint of exhibiting an effect of improving processability. Furthermore, from the viewpoints of abrasion resistance and fracture toughness, it is preferably less than 10 parts by mass, more preferably less than 8 parts by mass, and even more preferably less than 5 parts by mass. (Wax)

[0197] Wax is not particularly limited, and any of those commonly used in the tire industry can be suitably used. Examples of wax include, for example, a mineral-based wax, a plant-derived wax, and the like. The mineral-based wax refers to wax derived from mineral resources such as oil, natural gas, and the like. The plant-derived wax refers to wax derived from natural resources such as a plant, and the like. Among them, the mineral-based wax is preferable. Examples of the plant-derived wax include, for example, a rice wax, a carnauba wax, a candelilla wax, and the like. Examples of the mineral-based wax include, for example, a paraffin wax, a microcrystalline wax, specially selected waxes thereof, and the like. Among them, a paraffin wax is preferable.Furthermore, wax according to the present embodiment should not contain stearic acid. For example, waxes commercially available from Ouchi Shinko Chemical Industry Co., Ltd., Nippon Seiro Co., Ltd., Paramelt BV, etc. can be used. These waxes can be used alone, or two or more of them can be used in combination.

[0198] A wax content when combined based on 100 parts by mass of the rubber component is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass from the viewpoint of weather resistance of a rubber. Furthermore, from the viewpoint of preventing tire whitening due to blooming, it is preferably less than 10 parts by mass, more preferably less than 7.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Stearic acid)

[0199] The content of stearic acid when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass from the viewpoint of processability, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass. Furthermore, from the viewpoint of vulcanization rate, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Zinc oxide)

[0200] The content of zinc oxide when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass from the viewpoint of processability, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass. Furthermore, from the viewpoint of abrasion resistance, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (antioxidant)

[0201] Examples of the antioxidant include, but are not particularly limited to, a naphthylamine-based antioxidant such as phenyl-α-naphthylamine and the like; a diphenylamine-based antioxidant such as octylated diphenylamine, 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine and the like; a p-phenylenediamine-based antioxidant such as N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (77PD), N,N'-diphenyl-p-phenylenediamine (DPPD), N,N'-ditolyl-p-phenylenediamine (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), N,N'-di-2-naphthyl-p-phenylenediamine (DNPD), and the like; a quinoline-based antioxidant such as a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline, and the like;a monophenol-based antioxidant such as 2,6-di-t-butyl-4-methylphenol, a styrenated phenol, and the like; and bis-, tris-, and polyphenol-based antioxidants such as tetrakis[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane and the like. Among them, p-phenylenediamine-based antioxidants and quinoline-based antioxidants are preferred, and polymers of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and 2,2,4-trimethyl-1,2-dihydroquinoline are more preferred. As commercially available products, for example, products manufactured by Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinko Chemical Industry Co., Ltd., Flexsys, etc. can be used.

[0202] The content of an antioxidant when combined, based on 100 parts by mass of the rubber component, is preferably greater than 1.0 parts by mass, more preferably greater than 1.5 parts by mass, and even more preferably greater than 1.8 parts by mass from the viewpoint of ozone cracking resistance of a rubber. Furthermore, from the viewpoint of abrasion resistance and wet grip performance, it is preferably less than 4.0 parts by mass, more preferably less than 3.0 parts by mass, and even more preferably less than 2.5 parts by mass. < <vernetzungsmittel>>

[0203] The rubber composition forming the tread portion comprises an organic crosslinking agent as a crosslinking agent, and preferably comprises an organic crosslinking agent and sulfur. Each of the rubber compositions forming the sidewall and the strip apex preferably comprises sulfur as a crosslinking agent. (Organic crosslinking agent)

[0204] The organic crosslinking agent is not particularly limited as long as it can form crosslinked chains other than a polysulfide bond. Examples include, for example, an alkylphenol sulfur chloride condensate, sodium hexamethylene 1,6-bisthiosulfate dihydrate, a dithiocarbamic acid-based compound, dicumyl peroxide, and the like. Among them, a dithiocarbamic acid-based compound is preferred.

[0205] The dithiocarbamic acid-based compound is a compound containing dithiocarbamic acid, examples of which include 1,6-bis(N,N'dibenzylthiocarbamoyldithio)hexane and the like. Among them, 1,6-bis(N,N'dibenzylthiocarbamoyldithio)hexane is preferred.

[0206] The content of an organic crosslinking agent based on 100 parts by mass of the rubber component is preferably greater than 1.0 parts by mass, more preferably greater than 2.0 parts by mass, and even more preferably greater than 2.5 parts by mass from the viewpoint of the effects of the present invention. Furthermore, from the viewpoint of preventing deterioration, it is preferably less than 8.0 parts by mass, more preferably less than 6.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Sulfur)

[0207] As the sulfur, a powdered sulfur, an oil-processing sulfur, a precipitated sulfur, a colloidal sulfur, an insoluble sulfur, a highly dispersible sulfur, and the like can be used.

[0208] A sulfur content when combined based on 100 parts by mass of the rubber component is preferably greater than 0.5 parts by mass, more preferably greater than 1.5 parts by mass, even more preferably greater than 2.0 parts by mass, and particularly preferably greater than 2.5 parts by mass from the viewpoint of ensuring a sufficient vulcanization reaction. Moreover, from the viewpoint of preventing deterioration, it is preferably less than 8.0 parts by mass, more preferably less than 6.0 parts by mass, and even more preferably less than 5.0 parts by mass. In addition, a content of a vulcanizing agent, when an oily sulfur is used as the vulcanizing agent, should be a total content of pure sulfur contained in the oily sulfur. (vulcanization accelerator)

[0209] Examples of a vulcanization accelerator include, but are not particularly limited to, a sulfenamide-based vulcanization accelerator, a thiazole-based vulcanization accelerator, a guanidine-based vulcanization accelerator, a thiuram-based vulcanization accelerator, a thiourea-based vulcanization accelerator, a dithiocarbamic acid-based vulcanization accelerator, an aldehyde-amine-based vulcanization accelerator, an aldehyde-ammonia-based vulcanization accelerator, an imidazoline-based vulcanization accelerator, a xanthate-based vulcanization accelerator, a caprolactam disulfide, and the like. These vulcanization accelerators can be used alone, or two or more of them can be used in combination.Among them, one or more vulcanization accelerators selected from the group consisting of a sulfenamide-based vulcanization accelerator, a thiazole-based vulcanization accelerator, and a guanidine-based vulcanization accelerator are preferred from the viewpoint that suitable effects can be obtained more suitably.

[0210] Examples of a sulfenamide-based vulcanization accelerator include, for example, N-tert-butyl-2-benzothiazolylsulfenamide (TBBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N,N-dicyclohexyl-2-benzothiazolylsulfenamide (DCBS), and the like.

[0211] Examples of the thiazole-based vulcanization accelerator include, for example, 2-mercaptobenzothiazole (MBT) or a salt thereof, di-2-benzothiazolyl disulfide (MBTS), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(2,6-diethyl-4-morpholinothio)benzothiazole and the like.

[0212] Examples of the guanidine-based vulcanization accelerator include, for example, 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, di-o-tolylguanidine salt of dicacholborate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, 1,3-di-o-cumenyl-2-propionylguanidine and the like.

[0213] Examples of the thiuram-based vulcanization accelerator include, for example, tetrakis(2-ethylhexyl)thiuram disulfide (TOT-N), tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide, tetramethylthium monosulfide (TMTM), dipentamethylenethiuram disulfide, dipentamethylenethiuram tetrasulfide and the like.

[0214] Examples of the thiourea-based vulcanization accelerator include, for example, thiourea compounds such as thiocarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea and the like, N,N'-diphenylthiourea, trimethylthiourea, N,N'-diethylthiourea and the like.

[0215] Examples of the dithiocarbamate-based vulcanization accelerator include, for example, piperidinium pentamethylenedithiocarbamate (PPDC), zinc dimethyldithiocarbamate (ZnMDC), zinc diethyldithiocarbamate (ZnEDC), zinc dibutyldithiocarbamate (ZnBDC), zinc dibenzyldithiocarbamate (ZDBzC), zinc N-ethyl-N-phenyldithiocarbamate (ZnEPDC), zinc N-pentamethylenedithiocarbamate (ZnPDC), sodium dibutyldithiocarbamate (NaBDC), copper dimethyldithiocarbamate (CuMDC), iron dimethyldithiocarbamate (FeMDC), tellurium diethyldithiocarbamate (TeEDC) and the like.

[0216] A content of a vulcanization accelerator when combined based on 100 parts by mass of the rubber component (a total amount of all of a plurality of vulcanization accelerators when used in combination) is preferably more than 1.0 parts by mass, more preferably more than 1.5 parts by mass, and even more preferably 2.0 parts by mass or more. Furthermore, the content of the vulcanization accelerator based on 100 parts by mass of the rubber component is preferably less than 10 parts by mass, more preferably less than 8 parts by mass, and even more preferably less than 6 parts by mass.

[0217] In the present specification, various materials containing carbon atoms (e.g., rubber, oil, resin, vulcanization accelerator, antioxidant, surfactant, etc.) may be derived from carbon dioxide in the atmosphere. As a method of obtaining compounds of the various materials from carbon dioxide, carbon dioxide may be directly converted, or methane obtained through a methanation step for synthesizing methane from carbon dioxide may be converted. [Production]

[0218] The rubber composition according to the present embodiment can be produced by a known method. For example, it can be produced by kneading each of the above-described components using a rubber kneading device such as an open roll, a closed-type kneader (Bunbury mixer, kneader, etc.), and the like.

[0219] The kneading step includes, for example, a basic kneading step of kneading coupling agents and additives other than vulcanizing agents and vulcanization accelerators, and a final kneading step (F-kneading) of adding vulcanizing agents and vulcanization accelerators to the kneaded product obtained by the basic kneading step and kneading them. Furthermore, the basic kneading step can be divided into multiple steps if desired. In the case where the basic kneading step is divided, the method may be (1) a method of kneading some coupling agents and additives into a masterbatch in advance and then adding the remaining coupling agents and additives to the obtained masterbatch and kneading them; (2) a method of kneading all the coupling agents and additives at once in the basic kneading step and then rolling the kneaded product one or more times; or the like.In the method (1) described above, the number of masterbatches is not limited and can be two or more. Furthermore, when the number of masterbatches is two or more, all coupling agents and additives used in the basic kneading step can be assigned to any of the masterbatches.

[0220] Kneading conditions are not particularly limited. Examples of kneading include, for example, a method of kneading at a discharge temperature of 150 to 170°C for 3 to 10 minutes in the initial kneading step and a method of kneading at 70 to 110°C for 1 to 5 minutes in the final kneading step. Vulcanization conditions are not particularly limited. Examples of vulcanization include, for example, a method of vulcanizing at 150 to 200°C for 10 to 30 minutes.

[0221] The tire of the present embodiment, which has the tread portion, sidewall, and strip apex formed from the rubber composition according to the present embodiment, can be produced by a conventional method. That is, the tire can be produced by extruding an unvulcanized rubber composition prepared by combining each of the above-described components as required for a rubber component into shapes of a tread portion, a sidewall, and a strip apex, attaching each thus-obtained element together with other tire elements on a tire molding machine, and molding them by a conventional method for forming an unvulcanized tire, followed by heating and pressurizing the thus-obtained unvulcanized tire in a vulcanizing machine. A vulcanization condition is not particularly limited.Examples of vulcanization include, for example, a process of vulcanizing at 150 to 200 °C for 10 to 30 minutes. [Applications]

[0222] The tire of the present embodiment can be used for any application, regardless of whether it is a pneumatic tire or a pneumatic tire, and can be used as a passenger car tire, a large passenger car tire, a large SUV tire, a racing tire, a motorcycle tire, a heavy-duty tire, or a run-flat tire. Furthermore, the passenger car tire is a tire provided it is mounted on a car that runs on four wheels and refers to one with a maximum load capacity of less than 1400 kg. Furthermore, the heavy-duty tire refers to a tire with a maximum load capacity of 1400 kg or more. Furthermore, the tire of the present embodiment can be used as an all-season tire, a summer tire, or a winter tire, such as a studless tire and the like. EXAMPLES

[0223] Examples considered preferable in implementation (Examples) are shown below, but the scope of the present invention is not limited to Examples. Regarding tires having a tread portion, a sidewall, and a stripe apex produced using rubber compositions obtained by varying the compound shown in Table 1 using various chemicals shown below, results calculated based on the evaluation methods described below are shown in Tables 2 and 3. <Verschiedene Chemikalien> No.: TSR20 SBR: HP755, manufactured by Asahi Kasei Corporation (S-SBR, styrene content: 39.5 mass%, vinyl content: 38.2 mol%, containing 37.5 parts by mass of oil content based on 100 parts by mass of rubber component) BR: UBEPOL BR (registered trademark) 150B, manufactured by UBE Corporation (cis content: 97 mol%) Soot 1: Prototype (N2SA: 180 m 2 / g, average primary particle size: 16 nm) Soot 2: Show Black N220, manufactured by Cabot Japan KK (N2SA: 110 m 2 / g, average primary particle size: 22 nm) Carbon black 3: DIABLACK (registered trademark) E, manufactured by Mitsubishi Chemical Corporation (FEF, N550, N2SA: 40 m 2 / g, average primary particle size: 81 nm) Silicon dioxide: Ultrasil VN3, manufactured by Evonik Industries AG (N2SA: 175 m 2 / g, average primary particle size: 17 nm) Silane coupling agent: Si266, manufactured by Evonik Industries AG (bis(3-triethoxysilylpropyl) disulfide) Oil: VivaTec 500, manufactured by H&R Group (TDAE oil) Liquid rubber: L-SBR-820, manufactured by Kuraray Co., Ltd. (Liquid SBR) Resin component 1: Nitto Resin Coumarone V-120, manufactured by Nitto Chemical Co., Ltd. (coumarone-indene resin, softening point: 120 °C) Resin component 2: Petrotack 100V, manufactured by Tosoh Corporation (C5 / C9-based resin, copolymer of C5 fraction and C9 fraction, softening point: 96 °C) Antioxidant: Antigen 6C, manufactured by Sumitomo Chemical Co., Ltd. (N-(1,3-Dimethylbutyl)-N'phenyl-p-phenylenediamine) Wax: SUNNOC N, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Stearic acid: Stearic acid pearls "CAMELLIA", manufactured by NOF CORPORATION Zinc Oxide: Zinc Oxide No. 2, manufactured by Mitsui Mining & Smelting Co., Ltd. Sulfur: Powdered sulfur manufactured by Karuizawa Sulfur Co., Ltd. Organic crosslinking agent: VULCUREN (registered trademark) KA9188, manufactured by LANXESS (1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane) Vulcanization accelerator 1: Nocceler CZ, manufactured by Ouchi Shinko Chemical Industrial Co., Ltd. (N-cyclohexyl-2-benzothiazolylsulfenamide ((CBS)) Vulcanization accelerator 2: Nocceler D, manufactured by Ouchi Shinko Chemical Industrial Co., Ltd. (1,3-Diphenylguanidine (DPG)) (Examples and comparison examples)

[0224] According to the compound recipes shown in Table 1, using a 1.7-liter closed-type Banbury mixer, all chemicals other than sulfur, an organic crosslinking agent, and a vulcanization accelerator were kneaded for 4 minutes at a discharge temperature of 160°C to obtain a kneaded product. Next, using an open-type roll, sulfur, an organic crosslinking agent, and a vulcanization accelerator were added to the resulting kneaded product, and the mixture was kneaded for 4 minutes until a temperature reached 105°C to obtain an unvulcanized rubber composition.The obtained unvulcanized rubber composition is used to be molded into shapes of a tread portion, a sidewall, and a strip apex, and attached together with other tire elements to prepare an unvulcanized tire, which is then vulcanized at 170 °C to obtain each test tire (size: 205 / 65R15, rim: 15 × 6JJ, internal pressure: 230 kPa). <Messung von durch Aceton extrahierbarer Menge AE>

[0225] An acetone extractable amount is calculated by the following equation by immersing each rubber test piece produced by cutting out a tread portion, a sidewall, and a strip apex of each test tire in acetone at normal temperature (approximately 25 °C) for 72 hours to extract a soluble component, and measuring a mass of each rubber test piece before and after extraction in accordance with JIS K 6229:2015. (Amount extractable by acetone (mass %)) = {(Mass of rubber test piece before extraction - Mass of rubber test piece after extraction) / (Mass of rubber test piece before extraction)} × 100. <Messung von 30 C-E* T >

[0226] For each vulcanized rubber test piece produced by cutting out 20 mm long × 4 mm wide × 1 mm thick from the inside of each rubber layer of a tread portion of each test tire such that a tire circumferential direction becomes a long side and a tire radial direction becomes a thickness direction, a complex elastic modulus E* is measured using a dynamic viscoelasticity measuring device (EPLEXOR series, manufactured by gabo Systemtechnik GmbH) under a condition of a temperature of 30 °C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain of ±1%, and a stretching mode. <Messung von 70 °C-E* S >

[0227] For each vulcanized rubber test piece produced by cutting out 20 mm long × 4 mm wide × 1 mm thick from a sidewall of each test tire such that a tangent line to a tire circumferential direction becomes a long side and a tire width direction (a tangential direction on a surface of a sidewall) becomes a thickness direction, a complex elastic modulus E* is measured using a dynamic viscoelasticity measuring device (EPLEXOR series, manufactured by gabo Systemtechnik GmbH) under a condition of a temperature of 70 °C, a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ±1%, and a stretching mode. <Haftungsleistung beim Abbiegen>

[0228] The test tire is mounted on all wheels of a domestic FR vehicle (2000 cc), and actual vehicle driving with 10 laps is conducted on a test track with a dry asphalt road surface. Test drivers sensorily evaluate steering stability when a brake is applied and the vehicle turns while driving in a straight line at a speed of 100 km / h. Evaluations are performed using an integer value from 1 to 5 points, and a total score of 20 test drivers is calculated based on the evaluation criteria that the higher the score, the better the steering stability during steering. To evaluate grip performance during turning, two control tires are used, depending on the composition of a rubber composition forming a tread portion. The control tires are Comparative Example 1 in Table 2 and Comparative Example 4 in Table 3.The total score of each control tire is converted into a reference value (100), and the evaluation result for each test tire is expressed as an index proportional to the total score. The results show that the larger the numerical value, the higher the grip performance during turning. Table 1 Composite quantity T1 T2 T3 T4 T5 T6 T7 T8 Composite quantity (mass parts) NR - - - - - - - - SBR 137,5 137,5 137,5 137,5 137,5 137,5 137,5 137,5 (oil content) (37,5) (37,5) (37,5) (37,5) (37,5) (37,5) (37,5) (37,5) BR - - - - - - - - Soot 1 120 120 120 120 - - - - Soot 2 - - - - 10 10 10 10 Soot 3 - - - - - - - - Silicon dioxide - - - - 120 120 120 120 Silane coupling agents - - - - 12 12 12 12 Öl 10 10 50 70 - - 50 70 Liquid rubber - - - - - - - - Resin component 1 10 10 10 10 10 10 10 10 Resin component 2 - - - - - - - - Antioxidants 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 wax 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Stearic acid 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 zinc oxide 2,5 2,5 2,5 2,5 2,5 2,5 2,5 2,5 sulfur 2,0 1,5 1,5 1,5 2,0 1,5 1,5 1,5 Orange crosslinking agent - 3,0 3,0 3,0 - 3,0 3,0 3,0 Vulcanization accelerator 1 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Vulcanization accelerator 2 - - - - 3,0 3,0 3,0 3,0 Physical property AE amount (mass%) 22,0 22,0 31,0 35,0 18,0 17,0 30,0 34,0 30 °CE* (MPa) 34,0 35,0 19,0 15,0 34,0 33,0 13,0 10,0 70 °CE* (MPa) - - - - - - - - Total styrene amount (mass%) 40,0 40,0 40,0 40,0 40,0 40,0 40,0 40,0 Rubber hardness Hs 79 80 69 56 77 79 64 54 Composite quantity T9 T10 S1 S2 S3 A1 A2 A3 Composite quantity (mass parts) NR - 40 70 70 80 100 100 100 SBR 137,5 27,5 - - - - - - (oil content) (37,5) (7,5) - - - - - - BR - 40 30 30 20 - - - Soot 1 - 120 - - - - - - Soot 2 10 - - - - - - - Soot 3 - - 65 60 70 50 40 70 Silicon dioxide 120 - - - - - - - Silane coupling agents 12 - - - - - - - Öl 10 75 3 3 3 10 - - Liquid rubber 60 - - - - - - - Resin component 1 10 10 - - - - - - Resin component 2 - - 3 3 3 - - - Antioxidants 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 wax 2,0 2,0 1,5 1,5 1,5 1,5 1,5 1,5 Stearic acid 2,0 2,0 3,0 3,0 3,0 3,0 3,0 3,0 zinc oxide 2,5 2,5 4,0 4,0 4,0 4,0 4,0 4,0 sulfur 1,5 1,5 4,0 4,0 4,0 4,5 4,5 4,5 Organic crosslinking agent 3,0 3,0 - - - - - - Vulcanization accelerator 1 2,0 2,0 1,5 1,5 1,5 1,5 1,5 1,5 Vulcanization accelerator 2 3,0 - - - - - - - Physical property AE amount (mass%) 30,7 30,9 7,4 8,5 8,5 11,0 6,0 5,1 30 °CE* (MPa) 8,0 10,8 - - - - - - 70 °CE* (MPa) - - 8, 1 3, 2 4, 9 4,4 4,1 10,8 Total styrene amount (mass%) 40,0 8,0 0 0 0 0 0 0 Rubber hardness Hs 57 56 - - - - - - Table 2 Example Comparison example 1 2 3 4 5 6 7 8 9 1 2 3 Connection of tread section T2 T2 T2 T3 T4 T4 T4 T10 T4 T1 T2 T1 Connection of side wall S1 S1 S1 S1 S1 S2 S2 S1 S3 S1 S1 S1 Connection of strip apex A2 A2 A2 A2 A2 A2 A3 A2 A2 A1 A1 A2 AE1 (mass%) 22,0 22,0 22, 0 31, 0 35,0 35,0 35,0 30, 9 35,0 22, 0 22,0 22,0 AE2 (mass%) 7,4 7,4 7,4 7,4 7,4 8,5 8,5 7,4 8,5 7, 4 7,4 7,4 AE3 (mass %) 6,0 6,0 6,0 6,0 6,0 6,0 5,1 6,0 6,0 11,0 11,0 6,0 30 °CE* T (MPa) 35,0 35,0 35,0 19,0 15,0 15,0 15,0 10,8 15,0 34,0 35,0 34, 0 70 °CE* S (MPa) 8,1 8,1 8,1 8,1 8,1 3,2 3,2 8,1 4,9 8,1 8,1 8,1 Total styrene amount of tread section (mass%) 40,0 40,0 40,0 40,0 40,0 40,0 40,0 8,0 40,0 40,0 40,0 40,0 Survey ratio L 0,65 0,75 0,85 0,85 0,85 0,85 0,85 0,85 0,85 0,65 0,65 0,65 30°C* T × L 22,8 26,3 29, 8 16,2 12,8 12,8 12,8 9,2 12,8 22,1 22,8 22,1 AE3 × L 3,9 4,5 5,1 5,1 5,1 5,1 4,3 5,1 5,1 7,2 7,2 3,9 70°C* S × L 5,3 6,1 6,9 6,9 6,9 2,7 2,7 6,9 4,2 5,3 5,3 5,3 Hs of tread section 80 80 80 69 56 56 56 56 56 79 80 79 Hs × L of tread section 52,0 60,0 68,0 58,7 47,6 47,6 47,6 47,6 47,6 51,4 52,0 51,4 External elevation ratio Lo 0,74 0,83 0,89 0,89 0,89 0,89 0,89 0,89 0,89 0,74 0, 74 0,74 Internal elevation ratio Li 0,56 0,67 0,81 0,81 0,81 0,81 0,81 0,81 0,81 0,56 0,56 0,56 Lo-Li 0,18 0,16 0,08 0,08 0,08 0,08 0,08 0,08 0,08 0,18 0,18 0,18 AE1 × L 14,3 16,5 18,7 26,4 29,8 29,8 29, 8 26,3 29,8 14,3 14,3 14,3 Grip performance when turning 116 124 129 133 140 145 157 121 136 100 89 97 Table 3 Example Comparison example 10 11 12 13 14 15 16 17 4 5 6 Connection of tread section T6 T6 T6 T7 T8 T8 T8 T9 T5 T6 T5 Connection of side wall S1 S1 S1 S1 S1 S2 S2 S1 S1 S1 S1 Connection of strip apex A2 A2 A2 A2 A2 A2 A3 A2 A1 A1 A2 AE1 (mass %) 17,0 17,0 17,0 30,0 34,0 34,0 34,0 30,7 18,0 17,0 18,0 AE2 (mass%) 7,4 7,4 7,4 7,4 7,4 8,5 8,5 7,4 7,4 7,4 7,4 AE3 (mass %) 6, 0 6,0 6,0 6,0 6,0 6,0 5,1 6, 0 11,0 11,0 6,0 30 °CE* T (MPa) 33,0 33,0 33,0 13,0 10,0 10,0 10,0 8,0 34,0 33,0 34,0 70 °CE* S (MPa) 8,1 8,1 8,1 8,1 8,1 8,1 3,2 3,2 8,1 8,1 8,1 Total styrene amount of tread section (mass%) 40,0 40,0 40,0 40,0 40,0 40,0 40,0 40,0 40,0 40,0 40,0 Survey ratio L 0,65 0, 75 0,85 0,85 0,85 0, 85 0,85 0,85 0,65 0,65 0,65 30°C* T × L 21,5 24,8 28,1 11,1 8,5 8,5 8,5 6,8 22,1 21,5 22,1 AE3 × L 3,9 4,5 5,1 5,1 5,1 5,1 4,3 5,1 7,2 7,2 3,9 70°C* S × L 5,3 6,1 6,9 6,9 6,9 6,9 2,7 2,7 5,3 5,3 5,3 Hs of tread section 79 79 79 64 54 54 54 57 77 79 77 Hs × L of tread section 51,4 59,3 67,2 54,4 45,9 45,9 45,9 48,5 50,1 51,4 50,1 External elevation ratio Lo 0,74 0,83 0,89 0,89 0,89 0,89 0,89 0,89 0,74 0,74 0,74 Internal elevation ratio Li 0,56 0,67 0,81 0,81 0,81 0,81 0,81 0,81 0,56 0,56 0,56 Lo-Li 0,18 0,16 0,08 0,08 0,08 0,08 0,08 0,08 0,18 0,18 0,18 AE1 × L 11,1 12,8 14,5 25,5 28, 9 28, 9 28, 9 26,1 11,7 11,1 11,7 Grip performance when turning 109 118 121 127 130 140 148 139 100 92 95 <Ausführungsformen>

[0229] Examples of embodiments of the present invention are shown below. [1] A tire comprising a tread portion, a sidewall, a carcass and a strip apex, wherein the stripe apex is present on an inner side of the sidewall in a tire axial direction or on an inner side of a roll-back portion of the carcass in the tire axial direction, wherein the tread portion, the sidewall and the strip apex are formed from a rubber composition comprising a rubber component, where, when L represents a tire elevation ratio, L is 0.60 or more, wherein the rubber composition forming the tread portion comprises an organic crosslinking agent, and where, if AE1 represents in mass% an acetone-extractable amount of the rubber composition forming the tread portion, AE2 represents in mass% an acetone-extractable amount of the rubber composition forming the sidewall, and AE3 represents in mass% an acetone-extractable amount of the rubber composition forming the strip apex, AE1>AE2>AE3. [2] The tire of the above [1], where L is 0.70 or more. [3] The tire of the above [1] or [2], where L is 0.80 or more. [4] The tire of any one of the above [1] to [3], wherein a product (Hs × L) of a rubber hardness Hs of the rubber composition constituting the tread portion and L is less than 49. [5] The tyre of any of the above [1] to [4], wherein, when 30 °CE* T (MPa) represents a complex elastic modulus at 30 °C of the rubber composition constituting the tread portion, a product (30 °CE* T × L) from 30 °CE* T and L is less than 20 and preferably less than 17. [6] The tire of any of the above [1] to [5], wherein a product (AE3 × L) of AE3 and L is greater than 3.5. [7] The tyre of any of the above [1] to [6], wherein, when 70 °CE* S (MPa) represents a complex elastic modulus at 70 °C of the rubber composition forming the sidewall, a product (70 °CE* S × L) of 70 °CE* S and L is greater than 5.0. [8] The tire of any one of the above [1] to [7], wherein the organic crosslinking agent is a dithiocarbamic acid-based compound. [9] The tire of any one of the above [1] to [8], wherein the rubber composition forming the sidewall comprises, in the rubber component, 20 mass% or more of a butadiene rubber.

[10] The tire of any one of [1] to [9] above, wherein the rubber composition forming the sidewall comprises a resin component.

[11] The tire of any one of the above [1] to

[10] , wherein a total amount of styrene in the rubber component of the rubber composition constituting the tread portion is 20 mass% or more.

[12] The tire of any one of the above [1] to

[11] , wherein when in the tread portion at a centered tire equator Lo represents a lift ratio of a ground contact surface of an outer tread portion forming an end side outside a vehicle, and Li represents a lift ratio of a ground contact surface of an inner tread portion forming the end side outside the vehicle, an absolute value of a difference (Lo-Li) between Lo and Li is greater than 0 and less than 0.2, and preferably greater than 0.05 and less than 0.2.

[13] The tire of any one of the above [1] to

[12] , wherein AE3 is 4.0 mass% or more, and preferably 5.0 mass% or more.

[14] The tire of any one of the above [1] to

[13] , wherein AE1 × L is 14.0 or more, and preferably 16.5 or more.

[15] The tire of any one of the above [1] to

[14] , wherein the rubber composition constituting the tread portion comprises carbon black having an average primary particle size of 30 nm or less, preferably 25 nm or less, and more preferably 20 nm or less based on 100 parts by mass of the rubber component. LIST OF REFERENCE SYMBOLS 1 tread section 2 side wall 3 bead section 4 Carcass 5 strip apex 6 belt layer 7 inner liners 8 rim 9 Rim bead band 10 Clinch section 13 Bead Apex 14 Bead core 15 circumferential groove 16 Belt layer CL Tire Equator To outer tread end Ti inner tread end W Tire width direction C Tire circumferential direction o outer tread section i inner tread section 20 circumferential groove 21 circumferential groove 22 circumferential groove 23 footbridge section 24 side grooves 25 narrow circumferential groove 26 narrow side groove 27 inclined groove QUOTES CONTAINED IN THE DESCRIPTION

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

[0000] JP 2023-155706 A

[0003] JP 2009-2594 A

[0141] EP 3427975 A

[0151] JP 6856781 B [0151, 0152] EP 3173251 A

[0152] Cited non-patent literature

[0000] JATMA (The Japan Automobile Tire Manufacturers Association, Inc.)

[0039] Design Rim", die bei TRA (The Tire and Rim Association, Inc.) in „YEAR BOOK

[0039] MAXIMUM AIR PRESSURE" bei JATMA

[0040] JIS K 6239-2:2017 [0058, 0059] JIS K 6220-1:2015 7.7

[0064] Akita Prefectural University Web Journal B / 2019, vol. 6, S. 216-222

[0141] JIS K 6226-2:2003

[0150] Rubber Chemistry and Technology", Bd. 85, Nr. 3, Seiten 408 bis 449 (2012)

[0151] A comparison of surface morphology and chemistry of pyrolytic carbon blacks with commercial carbon blacks, Powder Technology 160 (2005) 190-193

[0151] Harima Chemicals Group, Inc., Arakawa Chemical Industries, Ltd., IREC Co., Ltd. etc

[0174] Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo K.K., ENEOS Corporation, Olisoy, H&R Group, Hokoku Corporation, Fuji Kosan Co., Ltd., The Nisshin OilliO Group, Ltd. etc

[0185] JIS K 6316:2017

[0192] < / vernetzungsmittel> < / gehalt> < / erweichungspunkt> < / plastifizierungsmittel> < / silankupplungsmittel> < / siliciumdioxid> < / kautschukkomponente> < / streifenapex> < / seitenwand>

Claims

[1] A tire comprising a tread portion, a sidewall, a carcass, and a strip apex, wherein the stripe apex is present on an inner side of the sidewall in a tire axial direction or on an inner side of a roll-back portion of the carcass in the tire axial direction, wherein the tread portion, the sidewall and the strip apex are formed from a rubber composition comprising a rubber component, where, when L represents a tire elevation ratio, L is 0.60 or more, wherein the rubber composition forming the tread portion comprises an organic crosslinking agent, and where, if AE1 represents in mass% an acetone-extractable amount of the rubber composition forming the tread portion, AE2 represents in mass% an acetone-extractable amount of the rubber composition forming the sidewall, and AE3 represents in mass% an acetone-extractable amount of the rubber composition forming the strip apex, AE1>AE2>AE3. [2] A tire according to claim 1, wherein L is 0.70 or more. [3] A tire according to claim 1 or 2, wherein L is 0.80 or more. [4] A tire according to any one of claims 1 to 3, wherein a product (Hs × L) of a rubber hardness Hs of the rubber composition constituting the tread portion and L is less than 49. [5] A tyre according to any one of claims 1 to 4, wherein when 30 °CE* T (MPa) represents a complex elastic modulus at 30 °C of the rubber composition constituting the tread portion, a product (30 °CE* T × L) from 30 °CE* T and L is less than 20. [6] A tire according to any one of claims 1 to 5, wherein a product (AE3 × L) of AE3 and L is greater than 3.

5. [7] A tyre according to any one of claims 1 to 6, wherein when 70 °CE* S (MPa) represents a complex elastic modulus at 70 °C of the rubber composition forming the sidewall, a product (70 °CE* S × L) from 70 °CE* S and L is greater than 5.

0. [8] A tire according to any one of claims 1 to 7, wherein the organic crosslinking agent is a dithiocarbamic acid-based compound. [9] A tire according to any one of claims 1 to 8, wherein the rubber composition forming the sidewall comprises, in the rubber component, 20 mass% or more of a butadiene rubber. [10] A tire according to any one of claims 1 to 9, wherein the rubber composition forming the sidewall comprises a resin component. [11] A tire according to any one of claims 1 to 10, wherein a total amount of styrene in the rubber component of the rubber composition constituting the tread portion is 20 mass% or more. [12] Tire according to one of claims 1 to 11, where, if in the tread portion at a centered tire equator Lo represents a lift ratio of a ground contact surface of an outer tread portion forming an end side outside a vehicle, and Li represents a lift ratio of a ground contact surface of an inner tread portion forming the end side outside the vehicle, an absolute value of a difference (Lo-Li) between Lo and Li is greater than 0 and less than 0.

2. [13] A tire according to any one of claims 1 to 12, wherein AE3 is 4.0 mass% or more. [14] A tire according to any one of claims 1 to 13, wherein AE1 × L is 14.0 or more. [15] A tire according to any one of claims 1 to 14, wherein the rubber composition forming the tread portion comprises carbon black having an average primary particle size of 30 nm or less.

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