TIRES

Abstract

A tire is provided comprising at least one tire element constructed from a rubber composition including recovered carbon black, wherein A, B, Wt and Dt simultaneously satisfy the following inequalities (1) and (2), where A represents a thickness in mm of the tire element, B represents a total carbon black content in parts by mass contained in the rubber composition, Wt represents a cross-sectional width in mm of the tire, and Dt represents an outer diameter in mm of the tire: (π / 4 ) × (Dt 2 / Wt ) ≥ 1700, (Dt 2 / Wt) / (B × A) > 20.

Description

TECHNICAL AREA

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

[0002] From the perspective of environmental problems and resource conservation, studies on energy savings in tires have also been carried out. For example, WO 2022 / 074932 describes a tire that exhibits improved fuel efficiency and the like by adjusting a tire weight in relation to the maximum load capacity of the tire, a tire size, and a tanδ of a rubber compound forming a tread within predetermined ranges. SUMMARY OF THE INVENTION

[0003] One object of the present invention is to provide a tire with improved fuel efficiency.

[0004] The present invention relates to: a tire comprising at least one tire element made of a rubber compound that includes recovered carbon black, where A, B, Wt and Dt simultaneously satisfy the following inequalities (1) and (2), where A represents a thickness in mm of the tire element, B represents a total content in parts by mass of carbon black contained in the rubber composition, Wt represents a cross-sectional width in mm of the tire and Dt represents an outer diameter in mm of the tire: (π / 4)×(Dt2 / Wt)≥1700, (Dt2 / Wt) / (B×A)>20.

[0005] According to the present invention, a tire with improved fuel efficiency can be provided. BRIEF DESCRIPTION OF THE DRAWINGS Fig.Figure 1 is a schematic view showing part of a tire meridian cross-section (upper right part of the cross-section) of a tire according to an embodiment of the present invention. Fig. Figure 2 is a view showing a tire cross-sectional width Wt and a tire outer diameter Dt in a cross-section of a tire. Fig. Figure 3 is a top view showing a ground contact area of ​​a tread of a tire according to an embodiment of the present invention. EXECUTIONAL FORMS FOR IMPLEMENTING THE INVENTION

[0006] The tire according to the embodiment of the present embodiment is a tire comprising at least one tire element composed of a rubber composition comprising recovered carbon black, wherein A, B, Wt and Dt simultaneously satisfy the following inequalities (1) and (2), where A represents a thickness in mm of the tire element, B represents a total carbon black content in parts by mass contained in the rubber composition, Wt represents a cross-sectional width in mm of the tire and Dt represents an outer diameter in mm of the tire: (π / 4)×(Dt2 / Wt)≥1700, (Dt2 / Wt) / (B×A)>20.

[0007] Although it is not intended to be bound to any theory, the following may be considered as a reason why fuel efficiency can be improved in the present embodiment.(1) By adjusting the outer diameter Dt and the cross-sectional width Wt in a predetermined relationship of inequality (1) and reducing the ground contact width of a tread section relative to a surface area on a sidewall of the tire, (a) heat generation derived from friction between the tire and a road surface can be reduced, and a temperature rise due to heat generation in the tread section can be suppressed, and (b) since the sidewall section of the tire is large, heat is easily dissipated from the tire as a whole, and the temperature of the tire and the sidewall section are prevented from becoming too high, (c) so that rolling resistance is assumed to be reduced.Furthermore, (2) is assumed that, since recovered carbon black absorbs more moisture than regular carbon black, the inclusion of recovered carbon black makes it easier to release heat generated during an interaction of the recovered carbon black with a rubber component. (3) It is assumed that both heat accumulation and heat generation in the tire can be suppressed by diluting the tire element (i.e., reducing a value of A in the tire element), reducing a content of carbon black in the rubber composition (i.e., reducing B), and then satisfying inequality (2). Then, it is assumed that the combined action of (1) to (3) described above will improve the fuel efficiency of the tire.

[0008] At least one tire element constructed from the rubber composition comprising the recovered carbon black is preferably at least one tire element selected from a base tread, a sidewall, a clinch apex, an insulation and an inner liner.

[0009] If these tire elements are each made from a rubber composition that includes recovered carbon black, heat generation and heat accumulation of the tire element are reduced, and heat dissipation properties are improved, so that fuel efficiency is assumed to be improved.

[0010] The right-hand side of inequality (1) is preferably 1800.

[0011] A tire that satisfies inequality (1) under a stricter condition is assumed to be further improved in terms of fuel efficiency.

[0012] The right-hand side of inequality (2) is preferred 23.

[0013] A tire that satisfies inequality (2) under a stricter condition is assumed to be further improved in terms of fuel efficiency.

[0014] It is preferred that at least one tire element, which is made up of the rubber composition comprising the recovered carbon black, is a base tread, and that a rubber composition forming the base tread comprises an isoprene-based rubber and a butadiene rubber, wherein a total content of the isoprene-based rubber and the butadiene rubber is greater than 80 wt%.

[0015] It is preferred that at least one tire element, which is made up of the rubber composition comprising the recovered carbon black, is a sidewall and that a rubber composition forming the sidewall comprises an isoprene-based rubber and a butadiene rubber, wherein a total content of the isoprene-based rubber and the butadiene rubber is greater than 80 wt%.

[0016] It is preferred that at least one tire element, which is made up of the rubber composition comprising the recovered carbon black, is a clinch apex and that a rubber composition forming the clinch apex comprises an isoprene-based rubber and a butadiene rubber, wherein a total content of the isoprene-based rubber and the butadiene rubber is greater than 80 wt%.

[0017] It is preferred that at least one tire element, which is made up of the rubber composition comprising the recovered carbon black, is an insulation and that a rubber composition forming the insulation comprises an isoprene-based rubber and a styrene-butadiene rubber, wherein a total content of the isoprene-based rubber and the styrene-butadiene rubber is greater than 80 wt%.

[0018] It is preferred that at least one tire element, which is made up of the rubber composition comprising the recovered carbon black, is an inner liner and that a rubber composition forming the inner liner comprises a butyl-based rubber, wherein the content of the butyl-based rubber is greater than 90 wt%.

[0019] It is preferred that the tread surface of the tire has two or more main circumferential grooves extending in a tire circumferential direction, a pair of shoulder rib sections on an outer side in a tire width direction, separated by a pair of outermost main circumferential grooves located on the outermost sides in the tire width direction below the main circumferential grooves, and middle rib sections sandwiched between the pair of shoulder rib sections, and that a negative rate of the middle rib section is greater than 0% and less than 15%.

[0020] By setting the negative rate of the central rib section to a predetermined ratio, the ground contact area of ​​the tread section is limited, and heat generation due to friction with a road surface is reduced, so that fuel efficiency is assumed to be improved.

[0021] A negative rate of the shoulder bridge segment is preferably greater than 20%.

[0022] By reducing the negative rate of the shoulder section and further reducing the ground contact area, heat generation due to friction with a road surface is reduced, so it is assumed that fuel efficiency is improved.

[0023] The total amount of styrene in mass % in the rubber component contained in the rubber composition is preferably less than 2.0.

[0024] The smaller the total amount of styrene, the smaller the number of domains formed by styrene units. This increases stiffness, which is assumed to reduce rolling resistance.

[0025] The silicon dioxide content contained in the rubber composition is preferably less than 10 parts by mass based on 100 parts by mass of the rubber component.

[0026] Stiffness is increased in an area of ​​small deformation, where it is assumed to reduce rolling resistance.

[0027] The rubber composition preferably includes resin.

[0028] The tire is preferably a tire for an electric vehicle.

[0029] The tire described above is excellent in terms of fuel efficiency, and it is expected to have a long driving range on a single charge. <definitionen>

[0030] A "standardized condition" is a state in which a tire is mounted on a standardized rim, filled with air at a standardized internal pressure, and no load is applied. Unless otherwise specified, a tire is used in this standardized condition.

[0031] A “dimension of each part of a tire” is, for one appearing on the outer surface of the tire, a value specified in a standardized condition unless otherwise specified, while for one present inside the tire or on a tire cut surface, it is a value specified in a condition in which, for example, the tire is cut on a plane with a tire axis of rotation and the cut piece of tire is held to a rim width of a standardized rim.

[0032] A "standardized rim" is a rim within a standard system that includes a standard on which the tire is based, and which is defined by the standard for each tire. For example, "standardized rim" refers to a standard rim of an applicable size described in the "JATMA YEAR BOOK" published by JATMA (The Japan Automobile Tire Manufacturers Association, Inc.), a "Measuring Rim" described in the "STANDARDS MANUAL" published by ETRTO (The European Tyre and Rim Technical Organisation), or a "Design Rim" described in the "YEAR BOOK" published by TRA (The Tire and Rim Association, Inc.), referenced in that order, and if an applicable size exists at the time of reference, the rim conforms to its standard.Furthermore, in the case of tires not defined by the standard, the standardized rim shall refer to a rim that can be fitted to the tire and whose width is the narrowest among rims that have the smallest diameter capable of maintaining internal pressure (i.e., causing no air leakage between the rim and the tire).

[0033] A “standardized internal pressure” is an air pressure in a standard system containing a standard on which the tire is based, 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 the “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES” table in TRA, to which reference is made in that 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.Furthermore, 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 several standardized internal pressures of 250 kPa or more are described, it shall refer to a minimum value below that.

[0034] A "standardized load in kg" is a load within a standard system that includes a standard on which the tire is based, defined by the standard for each tire, for example, a "MAXIMUM LOAD CAPACITY" for JATMA, a "LOAD CAPACITY" for ETRTO, or a maximum value described in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" table for TRA. Reference is made to this in that order, as in cases of a standardized rim and standardized inflation pressure, and if an applicable size exists 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 is... L defined as a standardized load.

[0035] The "maximum load capacity W" L in kg" is calculated using the following equations, where "V" is a virtual volume in mm³ 3 of a tire, "Dt" is the tire's outer diameter in mm in a standardized condition, "Ht" is the tire's cross-sectional height in mm in a tire radial direction in a cross-section of the tire in a plane containing a tire axis of rotation, and "Wt" is the tire's cross-sectional width in mm in a standardized condition. If R represents the rim diameter of the tire, Ht can be calculated as (Dt-R) / 2. Wt is a value obtained by excluding any patterns or markings on the tire's sidewall, if present. Additionally, "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

[0036] A “tire outer diameter Dt” refers to the outer diameter in mm of a tire in a standardized condition.

[0037] A “tire cross-sectional width Wt” refers to a maximum width in mm between outer surfaces of sidewalls in a standardized condition (excluding, if present, patterns or markings on a sidewall of a tire).

[0038] A "tire cross-sectional height Ht" refers to the radial height in mm of a tire in a cross-section of the tire along a plane containing a tire axis of rotation, and is equal to half the difference between a tire outer diameter Dt and a rim diameter R, where R represents the rim diameter of the tire. In other words, the cross-sectional height Ht can be calculated as (Dt-R) / 2.

[0039] A "tire weight" refers to the weight in kg of a single tire, excluding the weight of the rim. However, if the tire lumen contains an element made of a sponge or sealant, a sensor element, or the like, the weight should include this component.

[0040] A "tread section" is a section of a tread where a tire touches the ground when the tire is pressed against the ground, and a section of the tread that forms the effective ground contact area.

[0041] A "groove" refers to a recessed section formed on the tread surface of a tire (extending towards an inside in a tire radial direction) that has an opening width of 2.0 mm or more on the tread surface. A groove with a width of less than 2.0 mm refers to a "sipe".

[0042] A "circumferential groove" refers to a groove that extends continuously in one direction around the circumference of the tire. The circumferential groove can extend linearly along the circumference or it can extend in a wavy, sinusoidal, or zigzag pattern along the circumference. Furthermore, a "major circumferential groove" refers to one that has a groove width of 4 mm or more among the circumferential grooves.

[0043] A “groove width” means a length between groove edges on a tread surface in a cross-section of a tire along a plane that contains a tire axis of rotation.

[0044] A "tread section" is an element comprising a part that forms a ground contact area of ​​a tire, and in a case where the tire comprises an element forming a tire skeleton of steel or textile material, such as a belt layer, a belt reinforcement layer, a carcass layer and the like, in a cross-section in a tire radial direction, an element that is arranged on an outside of it in the tire radial direction.

[0045] A "negative rate" is a percentage ratio of groove area to ground contact area in a fixed region of a tread-ground contact area. The negative rate is calculated as the percentage ratio of the groove area present in each rib section to the center rib section and the shoulder rib section of the tread-ground contact area. Specifically, the area of ​​a ground contact shape of the center rib section and the shoulder rib section is measured after mounting a tire on a standardized rim, applying a standard internal pressure, and allowing it to stand at 25°C for 24 hours. This is followed by inking a tread surface of the tire with ink, applying a standardized load to press the tire against a piece of cardboard (a camber angle of 0°), and transferring the ink to the paper. (The area is referred to as the area of ​​a transferred rib section shape.)Furthermore, for each of the middle rib section and the shoulder rib section, an area of ​​a figure obtained by smoothly connecting contours of a ground contact shape is determined, which is defined as the total area of ​​each rib section (referred to as the total area of ​​a figure of a rib section obtained by connecting transferred contours). The negative rate is calculated for each of the middle rib section and the shoulder rib section by [1 - (Area of ​​transferred rib section shape) / (Total area of ​​figure of rib section obtained by connecting transferred contours)] × 100 (%).

[0046] A "thickness A of a tire element" is the thickness in mm of the tire element in a cross-section of the tire along a plane containing a tire axis of rotation. The thickness is measured by producing a tire section obtained by cutting the tire along the plane containing the tire axis of rotation, maintaining a distance between the beads of the tire section corresponding to a standardized rim width. The thickness is intended to be an average value of respective thicknesses measured at five points by rotating the tire 72°.

[0047] If the thickness of a tire element is substantially uniform throughout the tire's cross-section, then a thickness at a predetermined location is considered the thickness of the tire element. That is, (1) for elements whose thickness can be detected in a tire radial direction along a tire centerline, the thickness is considered to be the element's thickness, and (2) among tire elements whose thickness cannot be detected as described in (1), for elements whose thickness can be detected at the position of maximum tire width in a tire rotation axis direction, the thickness is considered to be the element's thickness. Examples of the tire element in (1) include a base tread, an inner liner, insulation, and the like. Furthermore, examples of the tire element in (2) include a sidewall and the like.

[0048] On the other hand, if the thickness of a tire element varies across the tire's cross-section, a thickness is determined using a standard thickness detection method for tire elements. Examples of such tire elements include a clinch apex and the like.

[0049] A "base tread thickness" is the thickness of a rubber layer as measured along a normal on a tire equator in a cross-section of a tire along a plane containing a tire axis of rotation. In a case where a circumferential groove is present on a tire equator, the thickness is the thickness of the rubber layer as measured along a normal on a central section in one tire width direction of a rib section, where the central section is closest in the tire width direction of the rib section to a tire equator plane, of rib sections present on both side faces in one tire width direction of the groove. Fig. 1 corresponds to T1, the thickness of the base running surface.

[0050] An “inner liner thickness” and an “insulation thickness” refer to a thickness in a tire radial direction for a layer of each element located at an equator in a cross-section of a tire along a plane containing a tire axis of rotation. If the elements are not present at the equatorial plane, the thickness is a thickness in a tire radial direction for a layer of the element at a central position in a tire width direction of the element. Fig. 1 corresponds to T2, the thickness of the insulation, and T3 corresponds to the thickness of the inner liner.

[0051] A “sidewall thickness” refers to the thickness in a direction parallel to a tire width direction of a rubber layer forming a sidewall, at a position where the distance between sidewalls on both sides in a cross-section of a tire along a plane containing a tire axis of rotation is longest. Fig. 1 corresponds to T4, the thickness of the side wall.

[0052] A "clinch apex thickness" refers to the thickness of the rubber layer as measured along a normal of a main body of a carcass passing through a point where a sidewall and the clinch apex on an outer surface of a tire come into contact. Fig. 1 is P1 a point where the sidewall and clinch apex come into contact on the outer surface of the tire, L1 is a normal of the main body of the carcass passing through point P1, and T5 is a thickness of the clinch apex as measured along normal L1.

[0053] For the "base tread thickness", "sidewall thickness", "clinch apex thickness", "insulation thickness", and "inner liner thickness", an average value is used of the respective values ​​measured at five points in a cross-section of a tire along a plane containing the tire's axis of rotation, after rotating the tire by 72°. Alternatively, the measurement can be taken after creating a cross-sectional piece of the tire along the plane containing the tire's axis of rotation and holding it in place, with a bead spacing adjusted to a standardized rim.

[0054] A “recovered carbon black” refers to carbon black obtained from a pyrolysis process for a product, such as a used tire or similar item, that contains carbon black, where, when the product is subjected to oxidative combustion by heating in air using a thermal weight measurement method in accordance with JIS K 6226-2:2003, the mass of ash (ash content), which is a component that does not combust, is 13% by mass or more. That is, the mass (amount of carbon) of weight loss due to oxidative combustion is 87% by mass or less. Recovered carbon black is also referred to as recycled carbon black or recycled carbon black and can be expressed as rCB. Furthermore, in this description, carbon black that is not recovered carbon black may be referred to as ordinary carbon black to distinguish it from recovered carbon black. <messverfahren>

[0055] A “styrene content” is determined by pyrolysis gas chromatography or NMR measurement ( 1 H-NMR or 13 Calc-NMR). Unlike physical property values, such as a complex elastic modulus (E*) and the like, a quantity of a component, such as the "styrene content," has a true value that is independent of the measurement method, so it is preferable to use a measurement method with the highest possible accuracy. Furthermore, in this description, "pyrolysis gas chromatography" refers to a process of heating a sample in a pyrolysis apparatus, separating individual components contained in the gas phase generated by this heating using a separation column, and analyzing each separated component.

[0056] A “vinyl content (unit amount of 1,2-bound butadiene)” is determined by pyrolysis gas chromatography or NMR measurement ( 1 H-NMR or 13 The vinyl content is calculated using C-NMR. Similar to the "styrene content", the "vinyl content" has a true value that is independent of the measurement method, so it is preferable to use a measurement method with the highest possible accuracy.

[0057] A “cis content (cis-1,4-bound butadiene unit amount)” is a value determined by infrared absorption spectrometry or NMR measurement ( 1 H-NMR or 13 The cis content is measured using ¹³C NMR according to JIS K 6239-2:2017 and is applied to a rubber component with a repeating unit derived from butadiene, such as a BR and the like. Similar to the styrene content, the cis content has a true value independent of the measurement method, so it is preferable to use a measurement method with the highest possible accuracy.

[0058] A "total styrene content in a rubber component" is the total mass-percentage of styrene units contained in 100 mass-percentage of a rubber component. This value is obtained by multiplying a styrene content in mass-percentage by a mass fraction in a rubber component to obtain a calculated value for each of the respective rubber components and then adding these values ​​together. Specifically, it is calculated as Σ(styrene content (mass-percentage) of each styrene-containing rubber × content (mass-percentage) of each styrene-containing rubber in the rubber component / 100). For example, if the rubber component consists of 30 wt% of a first SBR (styrene content: 25 wt%), 60 wt% of a second SBR (styrene content: 27.5 wt%), and 10 wt% of a BR, the total styrene content in 100 wt% of the rubber component is 24.0 wt% (= 25 × 30 / 100 + 27.5 × 60 / 100 + 0 × 10 / 100).

[0059] A "glass transition temperature (Tg) of a rubber composition" is a temperature corresponding to a maximum value (tanδ peak temperature) within a range of -60 °C or higher and 40 °C or lower, based on a temperature distribution curve of tanδ obtained by measurement under conditions of a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ± 0.5%, and a temperature rise rate of 2 °C / min using a dynamic viscosity measuring device (e.g., EPLEXOR series, manufactured by gabo Systemtechnik GmbH). Furthermore, when measured in the range of -60 to 40 °C, if the tanδ value continues to gradually increase or decrease as the temperature rises, the glass transition temperature of the rubber composition should be 40 °C or -60 °C, respectively.Furthermore, in the range of -60 °C or higher and 40 °C or lower, if there are two or more points indicating the maximum value, the point with the lowest temperature shall be a glass transition temperature.

[0060] A "weight-mean molecular weight (Mw)" can be calculated with respect to a standard polystyrene based on measurements 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). It is applied, for example, to an SBR, a BR, and the like.

[0061] The “ash content of recovered carbon black” is measured using a thermal weight measurement method according to JIS K 6226-2:2003.

[0062] An "average primary particle size" is a value obtained by photographing particles using a transmission or scanning electron microscope and calculating the arithmetic mean of the particle sizes of 400 particles. If the particle shape is spherical, a diameter of the sphere is defined as a particle size, and if the shape is not spherical, a circle-equivalent diameter (positive square root of {4 × (area of ​​particle) / π}) is calculated from the microscope image and defined as a particle size.

[0063] A “specific nitrogen adsorption surface (N2SA) of soot” is measured according to JIS K 6217-2:2017.

[0064] A “specific nitrogen adsorption surface (N2SA) of silicon dioxide” is measured by the BET method according to ASTM D3037-93. <reifen>

[0065] A tire according to one embodiment of the present invention is suitably described below with reference to the drawings. However, the drawings are merely examples for illustrative purposes.

[0066] Fig. Figure 1 is a schematic view showing part of a tire meridian cross-section (upper right part of the cross-section) of a tire according to an embodiment of the present invention. Fig. Figure 1 is a tread section comprising a ground contact area, consisting of a top tread containing a ground contact area, and a base tread 1 located on an inside of the top tread in a tire radial direction. Furthermore, a sidewall 4, located on an outside of the tread section in a tire width direction, and a clinch apex 5 extending from an end of the sidewall 4 to a rim are shown. [Further details are shown.] Fig. 1. An inner liner 3, which forms an inner surface of the tire, and an insulation 2, which is located on an outer surface of the inner liner 3 in a tire radial direction. Furthermore, the thickness of the base tread is designated T1, the thickness of the insulation is designated T2, the thickness of the inner liner is designated T3, the thickness of the sidewall is designated T4, and the thickness of the clinch apex is designated T5.

[0067] In one embodiment of the present invention, it is preferred that at least one tire element selected from the group consisting of a base tread, a sidewall, a clinch apex, insulation, and an inner liner comprises recovered carbon black. In another embodiment, it is preferred that at least one tire element selected from the group consisting of a base tread, a clinch apex, insulation, and an inner liner comprises recovered carbon black, and it is further preferred that at least one tire element selected from the group consisting of a base tread, insulation, and an inner liner comprises recovered carbon black.In a further embodiment, it is preferred that at least one tire element selected from the group consisting of a base tread, a sidewall, an insulation and an inner liner comprises recovered carbon black.

[0068] In a preferred embodiment, at least one tire element comprising recovered carbon black is a base tread. In a further preferred embodiment, at least one tire element comprising recovered carbon black is a clinch apex. In a further preferred embodiment, at least one tire element comprising recovered carbon black is a sidewall. In a further preferred embodiment, at least one tire element comprising recovered carbon black is an insulator. In a further preferred embodiment, at least one tire element comprising recovered carbon black is an inner liner.

[0069] In another preferred embodiment, tire elements, each comprising recovered carbon black, are at least two rubbers selected from the group consisting of a base tread, a clinch apex, an insulating rubber and an inner liner rubber, at least three rubbers selected from the group described above, or all from a base tread, a clinch apex rubber, an insulating rubber and an inner liner rubber.

[0070] Furthermore, in another preferred embodiment, a tire element comprising recovered carbon black is at least one element selected from the group consisting of a sidewall, a clinch apex, insulation, and an inner liner rubber. Alternatively, tire elements comprising recovered carbon black are at least two or three elements selected from the group described above, or all of which are a sidewall, a clinch apex rubber, an insulating rubber, and an inner liner rubber.

[0071] The tire according to the embodiment of the present embodiment is a tire comprising at least one tire element composed of a rubber composition comprising recovered carbon black, wherein A, B, Wt and Dt simultaneously satisfy the following inequalities (1) and (2), where A represents a thickness in mm of the tire element, B represents a total carbon black content in parts by mass contained in the rubber composition, Wt represents a cross-sectional width in mm of the tire and Dt represents an outer diameter in mm of the tire: (π / 4)×(Dt2 / Wt)≥1700, (Dt2 / Wt) / (B×A)>20. (Inequality (1))

[0072] If Dt increases, the value on the left-hand side of inequality (1) increases, and conversely, if Dt decreases, the value decreases. On the other hand, if Wt increases, the value on the left-hand side of inequality (1) decreases, and conversely, if Wt decreases, the value increases. By paying attention to this point, Dt and Wt can be adjusted to satisfy inequality (1).

[0073] The right-hand side of inequality (1) is preferably 1750, more preferably 1800, even more preferably 1850, even more preferably 1880, even more preferably 1900, even more preferably 1950, and even more preferably 2000. On the other hand, there is no particular upper limit for the value on the left-hand side of inequality (1), but it is usually about 2800 or may be about 2600.

[0074] The tire outer diameter Dt is preferably 585 mm or more, more preferably 600 mm or more, and even more preferably 625 mm or more. Furthermore, the tire outer diameter Dt is preferably less than 843 mm, more preferably less than 725 mm, and even more preferably less than 685 mm.

[0075] The tire cross-sectional width Wt is preferably 125 mm or more, more preferably 150 mm or more, and even more preferably 175 mm or more. Furthermore, the tire cross-sectional width Wt is preferably less than 305 mm, more preferably less than 245 mm, and even more preferably less than 210 mm.

[0076] Specific examples of a tire size that satisfies inequality (1) include 145 / 60R18, 145 / 60R19, 155 / 55R18, 155 / 55R19, 155 / 70R17, 155 / 70R19, 165 / 55R20, 165 / 55R21, 165 / 60R19, 165 / 65R19, 165 / 70R18, 175 / 55R19, 175 / 55R20, 175 / 55R22, 175 / 60R18, 185 / 55R19, 185 / 60R20, 195 / 50R20, 195 / 55R20 and the like. (Inequality (2))

[0077] The right-hand side of inequality (2) is preferably 23, more preferably 25, still more preferably 30, still more preferably 35, still more preferably 40, and still more preferably 50. On the other hand, there is no particular limit for an upper bound of a value on the left-hand side of inequality (2), but it is usually about 150, or may be about 120 or about 100.

[0078] On the left-hand side of inequality (2), the values ​​of Dt and Wt can be adjusted as described above. Furthermore, B can be adjusted by changing the amount of carbon black included in the rubber composition, and A can be adjusted by changing the thickness of the tire element described above. This allows for adjustments to the values ​​in inequality (2). (Negative rate of tread surface)

[0079] Fig. Figure 3 shows a ground contact surface shape when a standardized load is applied to a tire in a standardized condition according to an embodiment of the present invention. In the tire, a tread surface comprises shoulder rib sections 45, separated by a pair of outermost main circumferential grooves 41 located on the outermost side of the tire and extending in a circumferential direction, and middle rib sections 43, which are clamped between the shoulder rib sections. Fig. 3 Two circumferential grooves 42 are provided in the central web sections. In the present embodiment, each circumferential groove 42 extends linearly parallel to the tire's circumferential direction, but the circumferential groove 42 can, for example, extend in a wave shape.

[0080] Furthermore, in one embodiment, the negative rate of the central web section is preferably greater than 0% and less than 15%. The negative rate of the central web section is greater than 0%, preferably greater than 2%, more preferably greater than 4%, and even more preferably greater than 6%. In addition, the negative rate of the central web section is less than 15%, preferably less than 14%, more preferably less than 13%, and even more preferably less than 12%.

[0081] Furthermore, in one embodiment, the negative rate of the shoulder bridge section is preferably greater than 20%. The negative rate of the shoulder bridge section is more preferably greater than 23%, more preferably greater than 25%, more preferably greater than 28%, and more preferably greater than 30%. On the other hand, there is no particular upper limit, as long as a necessary guideline for the upper limit can be maintained, but it is, for example, less than 55%, preferably less than 50%, more preferably less than 45%, and more preferably less than 40%. (A)

[0082] The value of A is preferably 0.5 mm or more, more preferably 0.7 mm or more, and even more preferably 1 mm or more. On the other hand, the value is preferably 10 mm or less, more preferably less than 10 mm, even more preferably 9 mm or less, and even more preferably 8 mm or less.

[0083] The value of A can vary depending on the type of tire element. For the base tread, for example, the thickness of the base tread is preferably 1.0 mm or more, more preferably 1.5 mm or more, and still more preferably 2.0 mm or more. An upper limit to the value is not particularly restricted, but it is preferably 5.0 mm or less, more preferably 4.5 mm or less, and still more preferably 4.0 mm or less.

[0084] For example, the thickness of the side wall is preferably 1.0 mm or more, more preferably 1.5 mm or more, and even more preferably 2.0 mm or more. An upper limit to this value is not particularly restricted, but it is preferably 5.0 mm or less, more preferably 4.5 mm or less, and even more preferably 4.0 mm or less.

[0085] For the clinch apex, for example, the thickness of the clinch apex is preferably 4 mm or more, more preferably 4.5 mm or more, and even more preferably 5 mm or more. An upper limit to the value is not particularly restricted, but it is preferably 8 mm or less, more preferably 7 mm or less, and even more preferably 6 mm or less.

[0086] For example, the insulation thickness is preferably 0.1 mm or more, more preferably 0.5 mm or more, and even more preferably 0.7 mm or more. An upper limit to the value is not particularly restricted, but it is preferably 2 mm or less, more preferably 1.5 mm or less, and even more preferably 1.0 mm or less.

[0087] For the inner liner, for example, the thickness of the inner liner is preferably 0.5 mm or more, more preferably 0.7 mm or more, and even more preferably 1 mm or more. An upper limit to the value is not particularly restricted, but it is preferably 2.5 mm or less, more preferably 2 mm or less, and even more preferably 1.5 mm or less. <kautschukzusammensetzung>

[0088] A rubber composition used in a tire element forming the tire of the present embodiment is described. In the embodiment of the present invention, in at least one of the elements forming the tire, the rubber composition comprising the element includes recovered carbon black. In a preferred embodiment, examples of the tire element composed of the rubber composition comprising the recovered carbon black may include at least one tire element selected from a base tread, a sidewall, a clinch apex, an insulator, and an inner liner. A case in which each rubber composition, forming elements of a base tread, a clinch apex, a sidewall, an insulator, and an inner liner, comprises recovered carbon black is described below.Furthermore, in the following description, a rubber composition for each element, in a case where it does not include recovered carbon black, can be obtained by replacing recovered carbon black with regular carbon black. [Rubber composition for base tread]

[0089] Each component of a rubber compound for base tread is described. <kautschukkomponente>

[0090] It is preferred that the rubber composition forming the base tread includes a rubber component comprising an isoprene-based rubber (IR-based rubber) and a butadiene rubber (BR), and that the total content of the isoprene-based rubber and the butadiene rubber in 100 wt% of the rubber component is greater than 80 wt%. In this case, the rubber component may include rubber components other than an IR-based rubber and an SBR. Furthermore, the rubber component may be one consisting of an IR-based rubber and a BR. Examples of rubber components other than an IR-based rubber and a BR include, for example, a styrene-butadiene rubber (SBR) and other rubbers. Any rubber that may form a rubber component is described below. (Isoprene-based rubber)

[0091] Examples of isoprene-based rubber include natural rubber (NR), isoprene rubber (IR), refined NR, modified NR, modified IR, and the like. NR can include those commonly used in the tire industry, such as SIR20, RSS#3, TSR20, SVR-L, and similar rubbers. IR is not particularly restricted, and those commonly used in the tire industry, such as IR 2200, can be used.Examples of refined NR include deproteinized natural rubber (DPNR) and ultrapure natural rubber (UPNR), and the like; examples of modified NR include epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), and grafted natural rubber, and the like; and examples of modified IR include epoxidized isoprene rubber, hydrogenated isoprene rubber, grafted isoprene rubber, and the like. Isoprene-based rubber can be used alone, or two or more can be used in combination.

[0092] For example, the content of an IR-based rubber in 100 wt% of the rubber component is more than 10 wt%, preferably more than 20 wt%, more preferably more than 40 wt%, and even more preferably 50 wt% or more. On the other hand, the content is, for example, less than 95 wt%, preferably less than 90 wt%, and more preferably less than 80 wt%. If it is within the ranges described above, abrasion resistance is improved, and processability tends to be improved. (BR)

[0093] A butadiene rubber (BR) is not particularly restricted; examples include those commonly used in the tire industry, such as a high-cis BR, a BR containing a 1,2-syndiotactic polybutadiene crystal (SPB-containing BR), a butadiene rubber synthesized using a rare-earth-based catalyst (rare-earth-based BR), a tin-modified butadiene rubber modified by a tin compound (tin-modified BR), other modified butadiene rubbers (modified BR), and the like. Commercially available BRs include those from UBE Corporation, JSR Corporation, Asahi Kasei Corporation, Zeon Corporation, etc. A modified BR can be any BR that has a functional group interacting with a filler, such as silicon dioxide, etc.Examples include, for instance, an end-modified BR in which at least one end of a BR is modified with a compound (modifier) ​​having the functional group described above (end-modified BR having the functional group described above at the end), a main-chain-modified BR having the functional group described above on the main chain, a main-chain-and-end-modified BR having the functional group described above on the main chain and at the end (for example, a main-chain-and-end-modified BR having the functional group described above on the main chain and in which at least one end of the BR is modified with the modifier described above), an end-modified BR modified with a polyfunctional compound having two or more epoxy groups in one molecule,is modified (coupled) and introduced with a hydroxyl group or an epoxy group, and the like. Examples of the functional group described above include, for example, an amino group, an amide group, a silyl group, an alkoxysilyl group, an isocyanate group, an imino group, an imidazole group, a urea group, an ether group, a carbonyl group, an oxycarbonyl group, a mercapto group, a sulfide group, a disulfide group, a sulfonyl group, a sulfinyl group, a thiocarbonyl group, an ammonium group, an imide group, a hydrazo group, an azo group, a diazo group, a carboxyl group, a nitrile group, a pyridyl group, an alkoxy group, a hydroxyl group, an oxy group, an epoxy group, and the like. Furthermore, these functional groups may contain a substituent. Among these are an amino group (preferably an amino group,in which a hydrogen atom of an amino group is substituted by an alkyl group with 1 to 6 carbon atoms), an alkoxy group (preferably an alkoxy group with 1 to 6 carbon atoms) and an alkoxysilyl group (preferably an alkoxysilyl group with 1 to 6 carbon atoms) is preferred.

[0094] The cis content of a BR is preferably greater than 90 mol%, more preferably greater than 93 mol%, still more preferably greater than 95 mol%, and even more preferably 97 mol% or more. The cis content of the BR is measured using the measurement method described above.

[0095] BR products can be used, for example, from UBE Corporation, JSR Corporation, Asahi Kasei Corporation, Zeon Corporation, etc. A BR can be used alone, or two or more can be used in combination.

[0096] Furthermore, the content of a rubber compound (BR) in 100 wt% of the rubber component is, for example, more than 10 wt%, preferably more than 15 wt%, more preferably more than 20 wt%, and even more preferably 25 wt% or more. On the other hand, the content is, for example, less than 90 wt%, preferably less than 80 wt%, more preferably less than 70 wt%, and even more preferably less than 60 wt%. If it lies within the ranges described above, the effects of the present invention are demonstrated, and abrasion resistance is tended to be improved.

[0097] Furthermore, the total content of an IR-based rubber and a BR in 100 wt% of the rubber component is preferably greater than 80 wt%, more preferably greater than 90 wt%, even more preferably greater than 95 wt% and can be 100 wt%. (SBR)

[0098] Styrene-butadiene rubber (SBR) is not particularly restricted; examples include unmodified emulsion-polymerized styrene-butadiene rubber (E-SBR) and unmodified solution-polymerized styrene-butadiene rubber (S-SBR), as well as modified SBRs obtained by modifying these, such as modified emulsion-polymerized styrene-butadiene rubber (modified E-SBR) and modified solution-polymerized styrene-butadiene rubber (modified S-SBR). Examples of modified SBR include SBR modified at its end and / or main chain, SBR coupled with tin, a silicon compound, etc. (a modified condensate SBR or one with a branched structure, etc.), and the like.In addition to SBR, there are oil-extended SBRs, where a stretching oil is added to adjust flexibility, and non-oil-extended SBRs, where no stretching oil is added; both types can be used. Examples of such SBRs include those manufactured by JSR Corporation, Asahi Kasei Chemicals Co., Ltd., Zeon Corporation, ZS Elastomer Co., Ltd., etc. An SBR can be used alone, or two or more can be used in combination.

[0099] The styrene content of an SBR is preferably more than 15 wt%, more preferably more than 20 wt%, and even more preferably more than 23 wt%. Furthermore, from the perspective of fuel efficiency, the styrene content is preferably less than 40 wt%, more preferably less than 35 wt%, and even more preferably less than 30 wt%. The styrene content of the SBR is measured using the measurement method described above.

[0100] The vinyl content (unit amount of 1,2-bound butadiene) of an SBR is preferably more than 10 mol%, further preferably more than 15 mol%, and even more preferably more than 20 mol%. Furthermore, the amount of vinyl bonded is preferably less than 80 mol%, further preferably less than 50 mol%, and even more preferably less than 30 mol%. The vinyl content of the SBR is measured using the measurement method described above.

[0101] From the perspective of fuel efficiency, the glass transition temperature (Tg) of an SBR is preferably higher than -85 °C, more preferably higher than -80 °C, and still more preferably higher than -75 °C, and it is preferably lower than -30 °C, more preferably lower than -35 °C, and still more preferably lower than -40 °C. The Tg of the SBR is measured using the measurement method described above.

[0102] For fuel efficiency, the weight-average molecular weight (Mw) of an SBR is preferably 100,000 or more, more preferably 150,000 or more, and even more preferably 190,000 or more. Furthermore, for crosslink uniformity, etc., the Mw is preferably 2,500,000 or less, more preferably 2,000,000 or less, and even more preferably 1,000,000 or less. The Mw of the SBR is measured using the measurement method described above.

[0103] The content of an SBR in 100 wt% of the rubber component, when incorporated into the rubber component, is, for example, more than 10 wt%, preferably more than 20 wt%, further preferably more than 30 wt%, and even more preferably 40 wt% or more. Conversely, the content is, for example, 100 wt% or less, preferably less than 90 wt%, and further preferably less than 80 wt%. When it lies within the ranges described above, both adhesion performance and abrasion resistance tend to be excellent. (Other rubbers)

[0104] Other usable rubbers besides those described above are not particularly restricted, and rubbers used in the tire industry and the like may be used. Examples of other rubbers include, for instance, diene-based rubbers such as acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), styrene isoprene butadiene copolymer rubber (SIBR), and the like. Other rubbers may be used alone, or two or more of them may be used in combination. (Rubber component synthesized from recycled / biomass-derived raw material)

[0105] A monomer that is a structural unit of a synthetic rubber, such as SBR, BR, and the like, can be derived from underground resources, such as petroleum, natural gas, and the like, or recycled from a rubber product, such as a tire, and the like, or from a non-rubber product, such as polystyrene, and the like. A monomer obtained through recycling (recycled monomer) is not particularly restricted; examples include recycled polyisoprene, recycled butadiene, recycled aromatic vinyl compounds, and the like. Examples of butadiene include 1,2-butadiene, 1,3-butadiene, and the like. The aromatic vinyl compound described above is not particularly restricted, and examples include styrene and the like.Among these, recycled polyisoprene (a recycled polyisoprene), recycled butadiene (a recycled butadiene) and / or recycled styrene (a recycled styrene) are preferably used as a raw material.

[0106] A process for producing a recycled monomer is not particularly restricted; examples include, for instance, a process for synthesizing a monomer from recycled naphtha obtained by decomposing a rubber product, such as a tire, etc. Furthermore, a process for producing recycled naphtha is not particularly restricted and can, for example, be obtained by decomposing a rubber product, such as a tire, etc., under high temperature and high pressure, by decomposing it using microwaves, or by mechanical pulverization followed by extraction.

[0107] Furthermore, a monomer that is a structural unit of a polymer, such as an IR, an SBR, a BR, and the like, can be a biomass-derived monomer. In this description, biomass refers to material derived from natural sources, such as plants and the like. Biomass is not particularly restricted; examples include agricultural, forestry, and fishery products, sugar, wood waste, plant residues after the capture of a useful component, plant-derived ethanol, biomass naphtha, and the like.

[0108] The biomass-derived monomer (biomass monomer) is not particularly restricted; examples include biomass-derived butadiene, biomass-derived aromatic vinyl compounds, and the like. Examples of butadiene include 1,2-butadiene, 1,3-butadiene, and the like. The aromatic vinyl compound described above is not particularly restricted, and examples include styrene and the like. Furthermore, the method of producing a biomass monomer is not particularly restricted; examples include, for instance, one through biological and / or chemical and / or physical transformation of animals and plants, and the like.Microbial fermentation is representative of biological conversion, and examples of chemical and / or physical conversion include conversion due to a catalyst, conversion due to high heat, conversion due to high pressure, conversion due to an electromagnetic wave, conversion due to a critical fluid, and combinations thereof.

[0109] A polymer synthesized from a biomass monomer component (biomass polymer) is not particularly restricted; examples include butadiene rubber synthesized from biomass-derived butadiene, aromatic vinyl / butadiene copolymer synthesized from biomass-derived butadiene and / or a biomass-derived aromatic vinyl compound, and the like. Examples of aromatic vinyl butadiene copolymer include, for instance, styrene-butadiene rubber synthesized from biomass-derived butadiene and / or biomass-derived styrene, and the like.

[0110] Whether a polymer raw material is derived from biomass can be determined by pMC (percent modern carbon), measured according to ASTM D6866-10. 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 the biomass ratio of a compound. The meaning of this value is mentioned below.

[0111] In 1 mol of carbon atoms (6.02 × 10 23 (Pieces) are approximately 6.02 × 10 11 14 C are present, which are about one trillionth the number of normal carbon atoms. A half-life of 14 C is 5730 years, and 14 Carbon dioxide decreases regularly. Therefore, in the case of fossil fuels, such as coal, oil, natural gas, and the like, where it is assumed that 226,000 years or more have passed since carbon dioxide was absorbed into the atmosphere by plants to be fixed, all 14 Carbon elements that were present at the beginning of the fixation decay. Therefore, fossil fuels, such as coal, oil, natural gas, and the like, do not contain carbon in the current 21st century. 14 Carbon element. Therefore, chemical substances produced using these fossil fuels as raw materials also contain no carbon. 14 C-element.

[0112] on the other hand 14 C is constantly produced by cosmic rays that cause nuclear reactions in the atmosphere. Thus, a decrease of 14 C due to radioactive decay and the production of 14 C is balanced due to nuclear reactions and is the amount of 14 The temperature C in the Earth's atmospheric environment is constant. Therefore, the 14 Carbon concentration of substances derived from biomass resources circulating in the current environment, a value of approximately 1 × 10 -12 Molar percentages are based on total carbon atoms, as described above. Accordingly, by using the difference between these values, a biomass ratio in a given compound can be calculated.

[0113] 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) measured. During the measurements, a 14 Carbon 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 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 considered a standard. 14 A carbon concentration value (100%) is used. A ratio of this value to an actual measured value for a sample is called a pMC value.

[0114] Thus, when a rubber is produced from a material derived 100% from biomass, the 14 The carbon concentration has a value of approximately 110 pMC, which under normal conditions is often not equal to 100, although there are regional differences and the like. On the other hand, it shows that if these 14 When the carbon concentration of a chemical substance derived from a fossil fuel, such as petroleum, is measured, it will be approximately 0 pMC (for example, 0.3 pMC). This value corresponds to a biomass ratio of 0%, as mentioned above.

[0115] Based on the above, it is suitable in terms of environmental protection to use a material, such as a rubber with a high pMC value, and the like, that is, a material such as a rubber with a high biomass ratio, and the like, for a rubber composition. <Füllstoff>

[0116] A filler refers to a reinforcing filler, and in the present embodiment, a rubber composition forming at least one of the given tire elements comprises recovered carbon black (rCB). Furthermore, in the present embodiment, the filler, in addition to rCB, comprises both regular carbon black and another reinforcing filler used in the tire industry. If the filler comprises silicon dioxide, it may also include a silane coupling agent. (Recovered soot)

[0117] In the present embodiment of the present invention, recovered carbon black refers to carbon black obtained from a pyrolysis process for a product, such as a used tire and the like, comprising carbon black, wherein, when the product is subjected to oxidative combustion by heating in air using a thermal weight measurement method according to JIS K 6226-2:2003, the ratio of mass to ash (ash content), which is a non-combustible component, is 13% by mass or more. The ash content of the recovered carbon black is preferably 14% by mass or more, more preferably 15% by mass or more, still more preferably 16% by mass or more, and even more preferably 17% by mass or more.

[0118] The recovered carbon black can be obtained from a pyrolysis process of a used pneumatic tire. EP 3427975 A, for example, describes, with reference to “Rubber Chemistry and Technology”, Vol. 85, No. 3, pages 408 to 449 (2012), in particular pages 438, 440 and 442, that the recovered carbon black can be obtained by pyrolysis at 550 to 800 °C in the absence of oxygen or by vacuum pyrolysis at a relatively low temperature of an organic material (

[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 typically lacks a functional group on its surface.

[0119] 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, which is carried out so that the surface of the recovered carbon black includes a functional group, can be implemented by a conventional method. In EP3173251 A, carbon black comprising a hydroxyl and / or carboxyl group on its surface is obtained by treating carbon black obtained from a pyrolysis process with potassium permanganate under acidic conditions. Furthermore, in JP 6856781 B, carbon black with an activated surface is obtained by treating carbon black obtained from a pyrolysis process with an amino acid compound comprising at least one thiol 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.

[0120] The recovered carbon black can be that which is commercially available from Strebl Green Carbon Pte Ltd., LD Carbon, etc.

[0121] The average primary particle size of recovered carbon black is preferably 20 nm or more, more preferably 25 nm or more, still more preferably 30 nm or more, and particularly preferably 35 nm or more. When the average primary particle size of carbon black is within the ranges described above, the carbon black minimizes the size of rubber molecules, making them more flexible and allowing for easier movement. This is thought to reduce the stress on a polymer chain under an applied force. Conversely, the average primary particle size is preferably 90 nm or less, more preferably 75 nm or less, and still more preferably 60 nm or less. Furthermore, the average primary particle size of carbon black is measured using the measurement method described above.

[0122] A specific nitrogen adsorption surface area (N2SA) of recovered carbon black is preferably larger than 30 mm², in order to achieve sufficient reinforcing properties and good abrasion resistance. 2 / g, preferably larger than 40 m 2 / g, preferably larger than 50 m 2 / g, preferably larger than 60 m 2 / g and preferably larger than 70 m 2 / g, but it is not particularly limited to that. Furthermore, the N2SA is preferably less than 300 m, considering that carbon black is excellent in terms of dispersibility and is less likely to generate heat. 2 / g, preferably less than 200 m 2 / g, preferably less than 150 m 2 / g, preferably less than 120 m 2 / g, preferably less than 110 m 2 / g, preferably less than 100 m 2 / g and even more preferably less than 90 m 2 / g. Furthermore, the N2SA of the recovered carbon black in the present description is a value measured in accordance with JIS K 6217-2:2017.

[0123] The content of recovered carbon black, when combined, based on 100 parts by mass of the rubber component, is, for example, more than 1 part by mass, preferably more than 3 parts by mass, more preferably 5 parts by mass or more, and still more preferably 10 parts by mass or more. Conversely, the content is preferably less than 70 parts by mass, more preferably less than 65 parts by mass, and still more preferably 60 parts by mass or less. If the content of the recovered carbon black is within the ranges described above, sufficient reinforcing properties and good dispersion in the rubber are obtained, and sufficient rubber strength and fuel efficiency tend to be achieved. (soot that is different from rCB)

[0124] Carbon black other than recovered carbon black (regular carbon black) is not particularly restricted; examples include N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, N660, N762, and the like. A raw material for carbon black can be a biomass material, such as lignin, vegetable oil, and the like, or it can be pyrolysis oil obtained by pyrolyzing a used tire. Furthermore, a process for producing carbon black can be one by combustion, such as a furnace process, and the like; one by hydrothermal carbonization (HTC); or one by pyrolysis of methane, such as a thermal carbon black process, and the like. Commercially available products such as those 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.

[0125] The average primary particle size of carbon black is preferably 20 nm or more, more preferably 25 nm or more, still more preferably 30 nm or more, and particularly preferably 35 nm or more. When the average primary particle size of carbon black is within the ranges described above, the carbon black minimizes the size of rubber molecules, making them more flexible and allowing for easy movement. This is thought to reduce the stress on a polymer chain under an applied force. Conversely, the average primary particle size is preferably 90 nm or less, more preferably 75 nm or less, and still more preferably 60 nm or less. Furthermore, the average primary particle size of carbon black is measured using the measurement method described above.

[0126] A specific nitrogen adsorption surface area (N2SA) of carbon black is preferably greater than 30 mm², in order to obtain sufficient reinforcing properties and good abrasion resistance. 2 / g, preferably larger than 40 m 2 / g, preferably larger than 50 m 2 / g, preferably larger than 60 m 2 / g and preferably larger than 70 m 2 / g, but it is not particularly limited to that. Furthermore, the N2SA is preferably less than 300 m, considering that carbon black is excellent in terms of dispersibility and is less likely to generate heat. 2 / g, preferably less than 200 m 2 / g, preferably less than 150 m 2 / g, preferably less than 120 m 2 / g, preferably less than 110 m 2 / g, preferably less than 100 m 2 / g and even more preferably less than 90 m 2 / g. Furthermore, the N2SA of soot in the present description is a value measured in accordance with JIS K 6217-2:2017.

[0127] For example, the total content of recovered carbon black and other carbon black is more than 10 parts by mass, preferably more than 15 parts by mass, and more preferably 20 parts by mass or more, and still more preferably 30 parts by mass or more, based on 100 parts by mass of the rubber component. On the other hand, the total content is preferably less than 100 parts by mass, more preferably less than 95 parts by mass, and still more preferably less than 90 parts by mass. If the carbon black content is within the ranges described above, sufficient reinforcing properties and good dispersion in the rubber are obtained, and sufficient rubber strength and fuel efficiency tend to be achieved.

[0128] A ratio in % of the recovered soot content to the total content of recovered soot and other soot, i.e. a value of (recovered soot content) / (recovered soot content + other soot content) × 100, may be, for example, 50 or less, preferably 20 or less, more preferably less than 15, still more preferably less than 10 and still more preferably less than 5.

[0129] Furthermore, in the case where the recovered soot and other soot are combined as soot, once a total content of both and a content of the recovered soot have been determined, the remaining content of other soot is determined accordingly. (Silicon dioxide)

[0130] Silicon dioxide is not particularly restricted, and those commonly used in the tire industry can be employed, such as silicon dioxide produced by a dry process (anhydrous silicon dioxide), silicon dioxide produced by a wet process (hydrous silicon dioxide), and the like. The source of silicon dioxide is not particularly restricted and can include, for example, raw materials derived from minerals, such as quartz, and the like; raw materials derived from biomaterials, such as rice husks, and the like (e.g., silicon dioxide produced from a biomass material, such as rice husks, and the like); or silicon dioxide recycled from a silicon dioxide-containing product. Among these, hydrous silicon dioxide produced by a wet process is preferred because it contains many silanol groups.Silicon dioxide can be used alone, or two or more of them can be used in combination.

[0131] Silicon dioxide 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 silicon dioxide by reacting the silicate with sulfuric acid in the same way as for conventional wet silicon dioxide, and filtering, washing with water, drying, and pulverizing the silicon dioxide precipitates.

[0132] Silicon dioxide recycled from a product containing silicon dioxide can, for example, be recovered from an electronic component such as a semiconductor, a tire, a product containing silicon dioxide such as a desiccant, a filter material such as diatomaceous earth, etc. Furthermore, the recovery method is not particularly restricted; examples include pyrolysis, decomposition by electromagnetic waves, and the like. Silicon dioxide recovered from an electronic component such as a semiconductor or from a tire is preferred.

[0133] When silicon dioxide crystallizes, it is insoluble in water, and silicic acid, a component of it, cannot be used. Crystallization of silicon dioxide in rice hull ash can be suppressed by controlling the firing temperature and duration (JP 2009-2594 A, Akita Prefectural University Web Journal B / 2019, vol. 6, pp. 216-222, etc.). Amorphous silicon dioxide extracted from rice hulls, such as that commercially available from Wilmar, etc., can be used.

[0134] A specific nitrogen adsorption surface area (N2SA) of silicon dioxide is preferably greater than 50 m² from the perspective of its amplification properties. 2 / g, preferably larger than 100 m 2 / g, preferably larger than 150 m 2 / g and especially preferably larger than 170 m 2 / g. Furthermore, an upper limit for the N2SA of silicon dioxide is not particularly restricted, but it is preferably less than 350 m. 2 / g, preferably smaller than 250 m 2 / g and preferably smaller than 200 m 2 / g. If it lies within the ranges described above, cut strength tends to be improved. Furthermore, the N2SA of silicon dioxide is a value measured by a BET method according to ASTM D3037-93. (Silicon dioxide content)

[0135] The silicon dioxide content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 1 part by mass, more preferably more than 3 parts by mass, and even more preferably more than 5 parts by mass, from the perspective of ensuring fuel efficiency, but is not specifically limited to this. Furthermore, from the perspective of silicon dioxide dispersibility and processability, the content is preferably less than 50 parts by mass, more preferably less than 40 parts by mass, even more preferably less than 30 parts by mass, and even more preferably less than 10 parts by mass. In addition, in one embodiment of the present invention, the rubber composition may essentially comprise no silicon dioxide.Furthermore, in the present description, “does not include silicon dioxide” means that the silicon dioxide content is preferably 0.1 parts by mass or less, more preferably 0.01 parts by mass or less, and even more preferably 0 parts by mass based on 100 parts by mass of the rubber component. (Silane coupling agent)

[0136] When silicon dioxide is used as a filler, it is preferred that the rubber composition further comprises a silane coupling agent. Examples of silane coupling agents 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; and 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; chlorine-based silane coupling agents, such as 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxy, and the like, are acceptable, but not specifically limited to these. Sulfide-based and / or mercapto-based silane coupling agents are preferred. Examples of silane coupling agents that can be used include those commercially available from Evonik Industries AG, Momentive Performance Materials, etc. These silane coupling agents can be used individually, or two or more can be used in combination. (Content of silane coupling agent)

[0137] The content of a silane coupling agent, when combined, based on 1 part by mass of silicon dioxide, is preferably greater than 3 parts by mass, more preferably greater than 5 parts by mass, still more preferably greater than 7 parts by mass, and still more preferably greater than 100 parts by mass. Conversely, the content is preferably less than 20 parts by mass, more preferably less than 18 parts by mass, still more preferably less than 16 parts by mass, and still more preferably less than 14 parts by mass. If it is within the ranges described above, the dispersibility of silicon dioxide tends to be improved. Furthermore, if the rubber composition essentially contains no silicon dioxide, it also essentially contains no silane coupling agents.Here, “the rubber composition which essentially does not include silane coupling agents” means that the content of a silane coupling agent is preferably 0.1 parts by mass or less, more preferably 0.01 parts by mass or less, and even more preferably 0 parts by mass based on 100 parts by mass of the rubber component. (Other fillers)

[0138] Other fillers are not particularly restricted, and materials known in the tire industry can be used, examples of which include inorganic fillers such as calcium carbonate, talc, alumina, clay, aluminum hydroxide, aluminum oxide, mica, and the like, etc. They can be used alone, or two or more of them can be used in combination. <Andere Verbindungsmittel>

[0139] The rubber composition may, in addition to rubber components and fillers, appropriately include bonding agents that are conventionally and commonly used in the tire industry, such as a plasticizing agent, a processing aid, a vulcanized rubber particle, wax, stearic acid, zinc oxide, an antioxidant, a vulcanizing agent, a vulcanization accelerator, and the like. (Plasticizing agent)

[0140] A plasticizer is a material that imparts plasticity to the rubber component and encompasses both liquid plasticizers at 25°C and solid plasticizers at 25°C. Examples of plasticizers include resin, oil, liquid rubber, ester-based plasticizers, and the like. These plasticizers can be derived from mineral resources such as petroleum, natural gas, and the like, or derived from naphtha and recycled from a rubber or non-rubber product. Additionally, low molecular weight hydrocarbon components obtained by pyrolyzing end-of-life tires or products containing these agents and extracting them from the pyrolysate can be used as plasticizers.The plasticizing agent can be used alone, or two or more of them can be used in combination. < <harz>>

[0141] The rubber composition according to the present embodiment can include a resin component. The resin component that can be used in the present embodiment is not particularly restricted, and any resin commonly used in the tire industry can be used. Examples include, for instance, an adhesive resin such as a C9-based resin, a C5-based resin, a C5 / C9-based resin, an aromatic vinyl-based resin, a dicyclopentadiene-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.

[0142] A "C9-based resin" refers to a resin obtained by polymerizing C9 fractions and can be a resin 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. It can also be one obtained by hydrogenating or modifying it. Examples of C9 fractions include, for example, petroleum fractions with 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, coumaron, indene, methylindene, dicyclopentadiene, and the like.

[0143] 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 petroleum fractions from the group containing 4 to 5 carbon atoms, such as cyclopentadiene, isoprene, pentane, isopentane, neopentane, pentene, pentadiene, and the like.

[0144] One term, "C5 / C9-based resin," refers to resin obtained by copolymerizing the C5 and C9 fractions, and can be one obtained by hydrogenation or modification thereof. For example, suitable C5 / C9-based petroleum resins include those commercially available from Tosoh Corporation, Zibo Luhua Hongjin New Material Group Co., Ltd. Dicyclopentadiene-based resin

[0145] A "dicyclopentadiene resin" refers to a resin that contains dicyclopentadiene (DCPD) as the predominant monomer component and can be one obtained by hydrogenating or modifying it. Examples of dicyclopentadiene-based resins include, for instance, a DCPD / C9 resin obtained by copolymerizing dicyclopentadiene with the C9 fraction, and similar products. A DCPD / C9 resin is preferred. Examples of such DCPD resins include those commercially available from Exxon Mobil Corporation, ENEOS Corporation, Zeon Corporation, Maruzen Petrochemical Co., Ltd., etc. Aromatic resin on a vinyl base

[0146] An "aromatic vinyl-based resin" refers to a resin that incorporates an aromatic vinyl compound, such as styrene, α-methylstyrene, vinyltoluene, p-chlorostyrene, and the like, as a monomer component with the highest concentration, and may be one obtained by hydrogenation or modification thereof. A homopolymer of α-methylstyrene or styrene, or a copolymer of α-methylstyrene and styrene, is preferred as the aromatic vinyl-based resin, and a copolymer of α-methylstyrene and styrene is further preferred because it is economical, easy to process, and has excellent heat generation properties. Examples of aromatic vinyl-based resins that can be used include those commercially available from Kraton Corporation, Eastman Chemical Company, Mitsui Chemicals, Inc., etc. Coumaron-based resin

[0147] A coumaron-based resin refers to a resin that contains coumaron as a monomer component and may be one obtained by hydrogenation or modification thereof. Examples of coumaron resins include, for instance, a coumaron-indene resin, which contains coumaron and indene as monomer components, a coumaron-indene-styrene resin, which contains coumaron, indene, and styrene as monomer components, and the like. Indene-based resin

[0148] An indene-based resin refers to a resin that contains indene as a monomer component and can be one obtained by hydrogenating or modifying it. Examples of coumaron resin include, for instance, a coumaron-indene resin, which contains coumaron and indene as monomer components; a coumaron-indene-styrene resin, which contains coumaron, indene, and styrene as monomer components; and the like. Terpene-based resin

[0149] A terpene-based resin refers to a resin that incorporates a terpene compound, such as α-pinene, β-pinene, limonene, dipentene, and the like, as a monomer component with the highest concentration, and may be one obtained by hydrogenation or modification thereof. Specific examples of terpene-based resins include, for example, a polyterpene resin, which incorporates only one or more of the terpene compounds as monomer components; an aromatically modified terpene resin, which incorporates the terpene compound and an aromatic compound as monomer components; a terpenophenolic resin, which incorporates the terpene compound and a phenol-based compound as monomer components; and the like. Examples of the aromatic compound used as a monomer component for the aromatically modified terpene resin include, for example, styrene, α-methylstyrene, vinyltoluene, divinyltoluene, and the like.Examples of the phenol-based compound used as a monomer component for the terpene phenol resin include, for example, phenol, bisphenol A, cresol, xylenol and the like. Rosin-based resin

[0150] 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 hydrogenation or modification thereof. Examples of rosin-based resins include, but are not specifically limited to: natural resin rosin; and a rosin-modified resin obtained by modifying it through hydrogenation, disproportionation, dimerization, esterification, or the like; etc. Phenol-based resin

[0151] A phenol-based resin refers to a resin that contains a phenolic compound, such as phenol, cresol, and the like, as the predominant monomer component. Examples of phenol-based resins include, but are not limited to, phenol-formaldehyde resins, alkylphenol-formaldehyde resins, alkylphenol-acetylene resins, oil-modified phenol-formaldehyde resins, terpene phenol resins, and the like.

[0152] The resin content, when compounded, based on 100 parts by mass of the rubber component, is preferably more than 1 part by mass, more preferably more than 1.5 parts by mass, still more preferably 2 parts by mass or more, and still more preferably 3 parts by mass or more. Conversely, the content is preferably less than 40 parts by mass, more preferably less than 20 parts by mass, and still more preferably less than 10 parts by mass. (Other plasticizer than resin)

[0153] Oil, a liquid rubber, and an ester-based plasticizer, which are plasticizers other than resin, are described. <<Oil>>

[0154] Examples of oils include mineral oil, vegetable oil, animal oil, and the like. Furthermore, from a life cycle assessment perspective, oils obtained by cleaning used oil after use in a rubber mixer or engine, or used cooking oil from a restaurant, can be used. Oils can be used alone, or two or more can be used in combination.

[0155] In this description, a mineral oil refers to oil derived from mineral resources such as petroleum, natural gas, and the like. Examples of mineral oil include paraffinic oils (mineral oils), naphthenic oils, aromatic oils, and the like. Specific examples of 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. Additionally, as an environmental measure, an oil with a low content of polycyclic aromatic compounds (PCAs) may be used. Examples of oils with a low PCA content include MES, TDAE, heavy naphthenic oil, and the like. The mineral oil may be used alone, or two or more may be used in combination.

[0156] In this description, examples of vegetable oil include, for instance, 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, grapeseed oil, Japan wax, and the like. Furthermore, examples of vegetable oil also include refined oils obtained by refining the oils described above (cooking oils, etc.).), a transesterified oil obtained by transesterifying the oil described above, a hydrogenated oil obtained by hydrogenating the oil described above, a thermally polymerized oil obtained by thermally polymerizing the oil described above, an oxidized polymerized oil obtained by oxidizing the oil described above, a used cooking oil obtained by restoring what was previously used as an edible oil, etc., and the like. Furthermore, the vegetable oil may be liquid or solid at 25°C. The vegetable oil may be used alone, or two or more may be used in combination.

[0157] The vegetable oil according to the present embodiment preferably comprises acylglycerol and further preferably triacylglycerol. In this description, acylglycerol also refers to a compound in which a hydroxyl group of glycerol and a fatty acid are ester-bound. Acylglycerol is not particularly restricted and can be 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, or triacylglycerol. Furthermore, acylglycerol can be a monomer, a dimer, or a multimer that is a trimer or higher. Acylglycerol that is a dimer or higher can also be obtained by thermal polymerization, oxidative polymerization, or the like. Finally, acylglycerol can be liquid or solid at 25 °C.

[0158] As a method of checking whether the rubber composition includes acylglycerol, the test can be carried out, but is not particularly limited to 1 H-NMR measurement. For example, a heavy chloroform, wherein a rubber composition comprising triacylglycerol is immersed at 25 °C for 24 hours and then removed, 1 The samples were subjected to 1H NMR at room temperature, and signals close to 5.26 ppm, close to 4.28 ppm, and close to 4.15 ppm were observed under a condition where the signal from tetramethylsilane (TMS) was set to 0.00 ppm. It is suggested that the signals are derived from hydrogen atoms bonded to carbon atoms adjacent to oxygen atoms of an ester group. Furthermore, "close" in this paragraph refers to a range of ±0.10 ppm.

[0159] The fatty acid described above is not particularly restricted and can be either an unsaturated or a saturated fatty acid. Examples of unsaturated fatty acids include monounsaturated fatty acids, such as oleic acid, and the like, and polyunsaturated fatty acids, such as linoleic acid, linolenic acid, and the like. Furthermore, examples of saturated fatty acids include butyric acid, lauric acid, and the like.

[0160] The desired fatty acid is one with few double bonds, meaning a saturated or monounsaturated fatty acid, and oleic acid is preferred. A vegetable oil containing such a fatty acid can be, for example, a saturated or monounsaturated fatty acid, or it can be a vegetable oil modified by transesterification or similar processes. Furthermore, to produce a vegetable oil containing such a fatty acid, a plant can be improved through selective breeding, gene combination, genome editing, or similar methods.

[0161] For example, vegetable oils that are 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.

[0162] Examples of animal oil include fish oil, beef tallow, whale oil, oleyl alcohol derived from it, or the like.

[0163] The oil content, based on 100 parts by mass of the rubber component, is preferably greater than 1 part by mass, more preferably greater than 2 parts by mass, and even more preferably greater than 3 parts by mass or more. Furthermore, the content is preferably less than 20 parts by mass, more preferably less than 15 parts by mass, and even more preferably 10 parts by mass or less. The oil content also includes an amount of oil contained in the rubber component as an extender and an amount of oil contained in other components, such as sulfur and the like. <<Flüssigkautschuk> >

[0164] A liquid rubber is not particularly restricted as long as it is a polymer in a liquid state at 25 °C. Examples include liquid butadiene rubber (liquid BR), liquid styrene-butadiene rubber (liquid SBR), liquid isoprene rubber (liquid IR), liquid styrene-isoprene rubber (liquid SIR), liquid farnesene rubber, and the like. The liquid rubber can be used alone, or two or more can be used in combination. <<Plastifizierungsmittel auf Ester-Basis> >

[0165] Examples of ester-based plasticizers include 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. Ester-based plasticizers can be used alone, or two or more can be used in combination. (Vulcanized rubber particle)

[0166] A vulcanized rubber particle is a particle made from vulcanized rubber, and in particular, rubber powder and the like, as specified in JIS K 6316:2017, may be used. From an environmental and cost perspective, recycled rubber powder produced from a powdered end-of-life tire or the like is preferred. The vulcanized rubber particle may be used alone, or two or more may be used in combination.

[0167] The vulcanized rubber particle is not particularly restricted and can be an unmodified vulcanized rubber particle or a modified vulcanized rubber particle.

[0168] Commercially available vulcanized rubber products include, for example, products from Lehigh Technologies, Muraoka Rubber Reclaiming Co., Ltd., etc. (Processing aids)

[0169] Examples of processing aids include, for example, a fatty acid metal salt, a fatty acid amide, an amide ester, a silicon dioxide 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. The processing aid can be used alone, or two or more can be used in combination. Examples of processing aids that can be used include those commercially available from Schill+Seilacher GmbH, Performance Additives, etc.

[0170] 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 perspective of improving processability. Furthermore, from the perspective of abrasion resistance and fracture toughness, 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. (Wax)

[0171] The type of wax is not particularly restricted, and any wax commonly used in the tire industry may be suitable. Examples include mineral-based waxes, plant-derived waxes, and the like. Mineral-based waxes refer to waxes derived from mineral resources such as oil, natural gas, and the like. Plant-derived waxes refer to waxes derived from natural resources such as plants, and the like. Mineral-based waxes are preferred. Examples of plant-derived waxes include rice wax, carnauba wax, candelilla wax, and the like. Examples of mineral-based waxes include paraffin wax, microcrystalline wax, specially selected waxes thereof, and the like. Paraffin wax is preferred.Furthermore, according to the present embodiment, the wax 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. One wax can be used alone, or two or more can be used in combination.

[0172] The 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 perspective of improving the weather resistance of the rubber. Furthermore, from the perspective of preventing the whitening of a tire 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)

[0173] The stearic acid 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 0.7 parts by mass, and even more preferably 1.0 parts by mass or more, from the point of view of processability. On the other hand, from the point of view of vulcanization rate, the content is preferably less than 10 parts by mass, more preferably less than 5 parts by mass, and even more preferably less than 3 parts by mass. (Zinc oxide)

[0174] The zinc oxide 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 0.7 parts by mass, and even more preferably more than 1 part by mass, from the point of view of processability. On the other hand, from the point of view of abrasion resistance, the content is preferably 10 parts by mass or less, more preferably less than 7 parts by mass, and even more preferably 5 parts by mass or less. (Antioxidants)

[0175] Examples of the antioxidant include, but are not limited to, a naphthylamine-based antioxidant such as phenyl-α-naphthylamine and the like; a diphenylamine-based antioxidant such as an octylated diphenylamine, 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine and the like; an antioxidant based on p-phenylenediamine, 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; an antioxidant based on quinoline, 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 styrenized phenol, and the like; bis-, tris-, and polyphenol-based antioxidants, such as tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane and the like. Among these, p-phenylenediamine-based and quinoline-based antioxidants are preferred, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline are further preferred. Commercially available products may include, for example, those manufactured by Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinko Chemical Industry Co., Ltd., Flexsys, etc. The antioxidant can be used alone, or two or more of them can be used in combination.

[0176] The content of an antioxidant, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, further preferably more than 0.8 parts by mass, and even more preferably more than 1.0 parts by mass. On the other hand, the content is preferably less than 7.0 parts by mass, further preferably less than 5.0 parts by mass, and even more preferably 3.0 parts by mass or less. (Vulcanizing agent)

[0177] Sulfur is suitable for use as a vulcanizing agent. The vulcanizing agent can be used alone, or two or more can be used in combination.

[0178] Examples of sulfur include sulfur powder, precipitated sulfur, colloidal sulfur, surface-processed sulfur (oil-processing sulfur, special sulfur processed with a dispersant, masterbatch-type sulfur, etc.), insoluble sulfur (oil-processing insoluble sulfur, etc.), and the like, any of which may be used appropriately. Sulfur powder is preferred. Examples of sulfur that may be used include those manufactured and sold by Tsurumi Chemical Industry Co., Ltd., Karuizawa Sulfur Co., Ltd., Shikoku Chemicals Corporation, Flexsys, Nippon Kanryu Industry Co., Ltd., Hosoi Chemical Industry Co., Ltd., and the like.

[0179] As a vulcanizing agent other than sulfur, a known organic crosslinking agent can also be used. The organic crosslinking agent is not particularly restricted as long as it can form crosslinked chains other than polysulfide bonds. Examples include alkylphenol-sulfur chloride condensate, sodium hexamethylene 1,6-bisthiosulfate dihydrate, 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane, dicumyl peroxide, and the like. Among these, 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane is preferred. These organic crosslinking agents can include those commercially available from Taoka Chemical Co., Ltd., LANXESS, Flexsys, etc.

[0180] The content of a vulcanizing agent, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.4 parts by mass, more preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and more preferably more than 1.5 parts by mass. Conversely, the content is preferably less than 6.0 parts by mass, more preferably 5.0 parts by mass or less, and more preferably less than 4.0 parts by mass. If the content of the vulcanizing agent is within the ranges described above, a suitable strengthening effect is more likely to be obtained, and the effects of the present invention are more likely to be demonstrated. Furthermore, if the vulcanizing agent comprises a component other than sulfur, such as petroleum-based sulfur and the like, the content of the vulcanizing agent represents the content of the sulfur component itself. (Vulcanization accelerator)

[0181] Examples of vulcanization accelerators include, but are not limited to, sulfenamide-based vulcanization accelerators, thiazole-based vulcanization accelerators, guanidine-based vulcanization accelerators, thiuram-based vulcanization accelerators, thiourea-based vulcanization accelerators, dithiocarbamic acid-based vulcanization accelerators, aldehyde-amine-based vulcanization accelerators, aldehyde-ammonia-based vulcanization accelerators, imidazoline-based vulcanization accelerators, xanthate-based vulcanization accelerators, caprolactam disulfide, and the like. These vulcanization accelerators can be used individually, or two or more of them can be used in combination.Among these, one or more vulcanization accelerators are preferred, selected from the group consisting of a sulfenamide-based vulcanization accelerator, a thiazole-based vulcanization accelerator, and a guanidine-based vulcanization accelerator, based on the principle that suitable effects can be obtained more readily. The vulcanization accelerator can be used alone, or two or more can be used in combination.

[0182] Examples of sulfenamide-based vulcanization accelerators include, for example, N-tert-butyl-2-benzothiazolylsulfenamide (TBBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N,N-dicyclohexyl-2-benzothiazolylsulfenamide (DCBS), and the like.

[0183] Examples of thiazole-based vulcanization accelerators 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.

[0184] Examples of guanidine-based vulcanization accelerators include, for example, 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, di-o-tolylguanidine salt of dicatechol borate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, 1,3-di-o-cumenyl-2-propionylguanidine and the like.

[0185] Examples of thiuram-based vulcanization accelerators 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.

[0186] Examples of thiourea-based vulcanization accelerators 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.

[0187] Examples of dithiocarbamate-based vulcanization accelerators 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.

[0188] The content of a vulcanization accelerator based on 100 parts by mass of the rubber component is preferably greater than 0.3 parts by mass, more preferably greater than 0.4 parts by mass, and even more preferably greater than 0.5 parts by mass. Conversely, the content is preferably less than 4.0 parts by mass, more preferably less than 3.0 parts by mass, and even more preferably less than 2.0 parts by mass. If the content of the vulcanization accelerator is within the ranges described above, fracture strength and elongation tend to be ensured, and the effects of the present invention tend to be better demonstrated. [Rubber composition for sidewall]

[0189] Each component of a rubber composition for sidewalls is described. <kautschukkomponente>

[0190] The description for a rubber component is as below and as described for the rubber composition for the base tread. It is preferred that the rubber composition forming the sidewall comprises a rubber component consisting of an IR-based rubber and a butadiene rubber, and that the total content of the IR-based rubber and the butadiene rubber (BR) in 100 wt% of the rubber component is greater than 80 wt%. In this case, the rubber component may include rubber components other than an IR-based rubber and an SBR. Furthermore, the rubber component may be one consisting of a rubber selected from an IR-based rubber and a BR.Examples of rubber components other than IR-based rubber and BR include diene-based rubbers such as styrene-butadiene rubber (SBR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), and the like. The explanation given for the base tread rubber composition can be similarly applied to descriptions of these other rubber components. These other rubber components can be used alone, or two or more of them can be used in combination. (Salary)

[0191] The explanation for the content of a rubber component is as described for the section on the rubber composition for the base tread, but, for example, the content of an IR-based rubber in 100 wt% of the rubber component is more than 10 wt%, preferably more than 20 wt%, further preferably more than 40 wt%, and even more preferably 50 wt% or more. On the other hand, the content is, for example, 100 wt% or less, preferably less than 90 wt%, and further preferably less than 80 wt%. If it is within the ranges described above, abrasion resistance and processability tend to be improved.

[0192] For example, the content of a rubber compound (BR) in 100 wt% of the rubber component is more than 10 wt%, preferably more than 20 wt%, and more preferably more than 30 wt%. Conversely, the content is, for example, less than 90 wt%, preferably less than 80 wt%, more preferably less than 70 wt%, and even more preferably less than 60 wt%. If it lies within the ranges described above, abrasion resistance tends to be improved.

[0193] The total content of an IR-based rubber and a BR in 100 wt% of the rubber component is preferably greater than 80 wt%, more preferably greater than 90 wt%, even more preferably greater than 95 wt% and can be 100 wt%.

[0194] The content of an SBR in 100 wt% of the rubber component, when bonded, is, for example, more than 10 wt%, preferably more than 20 wt%, and further preferably more than 30 wt%. On the other hand, the content is, for example, less than 90 wt%, preferably less than 80 wt%, further preferably less than 70 wt%, and even more preferably less than 60 wt%. If it is within the ranges described above, adhesion performance and abrasion resistance tend to be improved. <Füllstoff>

[0195] A filler may comprise recovered carbon black (rCB), carbon black other than rCB, and silicon dioxide. If the filler comprises silicon dioxide, it may further comprise a silane coupling agent. The filler may also comprise fillers other than carbon black and silicon dioxide. An explanation for each component that may constitute the filler is as described below and as described in the section on the rubber composition for the base tread. (Soot content)

[0196] The recovered carbon black content, based on 100 parts by mass of the rubber component, is, for example, more than 2 parts by mass, preferably more than 3 parts by mass, further preferably more than 5 parts by mass, and even more preferably 7 parts by mass or more. On the other hand, the content is preferably less than 60 parts by mass, further preferably less than 55 parts by mass, and even more preferably less than 50 parts by mass. The total content of the recovered carbon black and other carbon black is, for example, more than 20 parts by mass, preferably more than 25 parts by mass, and even more preferably 30 parts by mass or more, based on 100 parts by mass of the rubber component. On the other hand, the total content is preferably less than 100 parts by mass, further preferably less than 90 parts by mass, and even more preferably less than 80 parts by mass.If the carbon black content is within the ranges described above, sufficient reinforcing properties and good dispersion will be obtained in a rubber, and sufficient rubber strength and fuel efficiency will tend to be achieved. (Silicon dioxide content)

[0197] The explanation given for the rubber composition for the base tread can be similarly applied to a silicon dioxide content, if combined. (Content of silane coupling agent)

[0198] The explanation given for the rubber composition for the base tread can be similarly applied to the content of a silane coupling agent, if combined. (Other connecting means)

[0199] The explanation given for the rubber composition for the base tread can be similarly applied to descriptions other than those above. [Rubber composition for Clinch-Apex]

[0200] Each component of a rubber composition for clinch apex is described. <kautschukkomponente>

[0201] The description for a rubber component is as below and as described for the rubber composition of the base tread. It is preferred that the rubber composition forming the clinch apex comprises a rubber component consisting of an IR-based rubber and a butadiene rubber, and that the total content of the IR-based rubber and the butadiene rubber in 100 wt% of the rubber component is greater than 80 wt%. In this case, the rubber component may include rubber components other than an IR-based rubber and an SBR. Furthermore, the rubber component may be one consisting of a rubber selected from an IR-based rubber and a BR.Examples of rubber components other than IR-based rubber and BR include diene-based rubbers such as styrene-butadiene rubber (SBR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), and the like. The explanation given for the base tread rubber composition can be similarly applied to descriptions of these other rubber components. These other rubber components can be used alone, or two or more of them can be used in combination. (Salary)

[0202] For example, the content of an IR-based rubber in 100 wt% of the rubber component is more than 30 wt%, preferably more than 40 wt%, further preferably more than 45 wt%, and even more preferably 50 wt% or more. On the other hand, the content is, for example, 100 wt% or less, preferably less than 95 wt%, and further preferably less than 90 wt%.

[0203] Furthermore, the content of a BR in 100 wt% of the rubber component is, for example, more than 10 wt%, preferably more than 20 wt%, more preferably more than 30 wt%, and even more preferably more than 40 wt%. On the other hand, the content is, for example, less than 90 wt%, preferably less than 80 wt%, more preferably less than 70 wt%, and even more preferably less than 60 wt%.

[0204] The total content of an IR-based rubber and a BR in 100 wt% of the rubber component is preferably greater than 80 wt%, more preferably greater than 90 wt%, even more preferably greater than 95 wt% and can be 100 wt%. <Füllstoff>

[0205] A filler may comprise recovered carbon black (rCB), carbon black other than rCB, and silicon dioxide. If the filler comprises silicon dioxide, it may further comprise a silane coupling agent. The filler may also comprise fillers other than carbon black and silicon dioxide. An explanation for each component that may constitute the filler is as described in the section on the rubber composition for the base tread. (Soot content)

[0206] The recovered carbon black content, based on 100 parts by mass of the rubber component, is, for example, more than 2 parts by mass, preferably more than 3 parts by mass, further preferably more than 5 parts by mass, and even more preferably 7 parts by mass or more. On the other hand, the content is preferably less than 60 parts by mass, further preferably less than 55 parts by mass, and even more preferably less than 50 parts by mass. The total content of the recovered carbon black and other carbon black is, for example, more than 20 parts by mass, preferably more than 25 parts by mass, and even more preferably 30 parts by mass or more, based on 100 parts by mass of the rubber component. On the other hand, the total content is preferably less than 100 parts by mass, further preferably less than 90 parts by mass, and even more preferably less than 80 parts by mass.If the carbon black content is within the ranges described above, sufficient reinforcing properties and good dispersion will be obtained in a rubber, and sufficient rubber strength and fuel efficiency will tend to be achieved. (Silicon dioxide content)

[0207] The explanation given for the rubber composition for the base tread can be similarly applied to a silicon dioxide content, if combined. (Content of silane coupling agent)

[0208] The explanation given for the rubber composition for the base tread can be similarly applied to the content of a silane coupling agent, if combined. (Other connecting means)

[0209] The rubber composition preferably includes resin. The explanation given for the rubber composition for the base tread can be applied similarly to descriptions other than those above. [Rubber composition for insulation]

[0210] Each component of a rubber composition for insulation is described. <kautschukkomponente>

[0211] The description for a rubber component is as below and as described for the rubber composition for the base tread. Preferably, the rubber composition forming the insulation comprises a rubber component consisting of an IR-based rubber and a styrene-butadiene rubber (SBR), and the total content of the IR-based rubber and the SBR in 100 wt% of the rubber component is greater than 80 wt%. In this case, the rubber composition may include rubber components other than the IR-based rubber and the SBR. Furthermore, the rubber component may be one consisting of a rubber selected from an IR-based rubber and an SBR.Examples of rubber components other than IR-based rubber and SBR include diene-based rubbers such as butadiene rubber (BR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and the like. The explanation given for the base tread rubber composition can be similarly applied to descriptions of these other rubber components. These other rubber components can be used alone, or two or more of them can be used in combination. (Salary)

[0212] For example, the content of an IR-based rubber in 100 wt% of the rubber component is more than 20 wt%, preferably more than 25 wt%, more preferably more than 30 wt%, and even more preferably 35 wt% or more. On the other hand, the content is, for example, 100 wt% or less, preferably less than 95 wt%, and more preferably less than 90 wt%.

[0213] Furthermore, the content of an SBR in 100 wt% of the rubber component is, for example, more than 10 wt%, preferably more than 15 wt%, and more preferably 20 wt% or more. On the other hand, the content is, for example, less than 90 wt%, preferably less than 80 wt%, more preferably less than 70 wt%, and even more preferably less than 60 wt%.

[0214] Furthermore, the total content of an IR-based rubber and an SBR in 100 wt% of the rubber component is preferably greater than 80 wt%, more preferably greater than 90 wt%, and even more preferably greater than 95 wt%, or can be 100 wt%. If it is within the ranges described above, processability and abrasion resistance tend to be improved. <Füllstoff>

[0215] A filler may comprise recovered carbon black (rCB), carbon black other than rCB, and silicon dioxide. If the filler comprises silicon dioxide, it may further comprise a silane coupling agent. The filler may also comprise fillers other than carbon black and silicon dioxide. An explanation for each component that may constitute the filler is as described in the section on the rubber composition for the base tread. (Soot content)

[0216] The recovered carbon black content, based on 100 parts by mass of the rubber component, is, for example, more than 2 parts by mass, preferably more than 3 parts by mass, further preferably more than 5 parts by mass, and even more preferably 10 parts by mass or more. On the other hand, the content is preferably less than 90 parts by mass, further preferably less than 80 parts by mass, and even more preferably less than 70 parts by mass. The total content of the recovered carbon black and other carbon black, based on 100 parts by mass of the rubber component, is, for example, more than 20 parts by mass, preferably more than 25 parts by mass, and even more preferably 30 parts by mass or more. On the other hand, the total content is preferably less than 100 parts by mass, further preferably less than 90 parts by mass, and even more preferably less than 80 parts by mass.If the carbon black content is within the ranges described above, sufficient reinforcing properties and good dispersion will be obtained in a rubber, and sufficient rubber strength and fuel efficiency will tend to be achieved.

[0217] For other carbon black (including recovered carbon black), the explanation given for the rubber composition for Clinch-Apex can be applied similarly. (Silicon dioxide content)

[0218] The explanation given for the rubber composition of Clinch-Apex can be similarly applied to a silicon dioxide content, if combined. (Content of silane coupling agent)

[0219] The explanation given for the rubber composition for Clinch-Apex can be similarly applied to the content of a silane coupling agent, if combined. (Other connecting means)

[0220] The rubber composition preferably includes resin. The explanation given for the rubber composition of Clinch-Apex can be similarly applied to descriptions other than those above. [Rubber composition for inner liner]

[0221] Each component of a rubber composition for inner liners is described. <kautschukkomponente>

[0222] The description for a rubber component is as below and as described for the rubber composition for Clinch-Apex. It is preferred that the rubber composition for the inner liner includes a rubber component comprising a butyl-based rubber, and that the content of the butyl-based rubber in 100 wt% of the rubber component is greater than 90 wt%. In this case, the rubber composition may include rubber components other than butyl-based rubbers. In this case, it preferably includes an isoprene-based rubber. The rubber component may be one consisting of a butyl-based rubber. (Butyl-based rubber)

[0223] The butyl-based rubbers are preferred if they comprise an isobutylene unit and an isoprene unit as repeating units, and a derivative thereof. Examples of such butyl-based rubbers include butyl rubber (IIR); halogenated butyl rubber, such as brominated butyl rubber (Br-IIR), chlorinated butyl rubber (Cl-IIR), and the like. Among these, halogenated butyl rubber is preferred, and brominated butyl rubber and chlorinated butyl rubber are further preferred because they allow for a good balance between sheet processability and air barrier properties. These can be used individually, or two or more can be used in combination.

[0224] Recycled butyl rubber and regular butyl rubber (butyl rubbers that differ from recycled butyl rubber) can be used as butyl rubber compounds in combination. Recycled butyl rubber typically has a high content of non-halogenated butyl rubber (regular butyl rubber), and therefore, using it in combination with halogenated butyl rubber ensures good air barrier properties and vulcanization rates. This recycled butyl rubber can be used alone, or two or more can be used in combination.

[0225] The rubber component may include other rubber components besides a butyl-based rubber. Examples of other rubber components include diene-based rubbers, such as isoprene-based rubber (IR-based rubber), butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and the like. The explanation given for the base tread rubber composition can be similarly applied to descriptions of these other rubber components. These other rubber components may be used alone, or two or more of them may be used in combination. (Salary)

[0226] From the perspective of sufficient air barrier properties, the content of a butyl-based rubber in 100 wt% of the rubber component is preferably more than 90 wt%, further preferably more than 92 wt% and even more preferably more than 95 wt%. <Füllstoff>

[0227] A filler may comprise recovered carbon black (rCB), carbon black other than rCB, and silicon dioxide. If the filler comprises silicon dioxide, it may further comprise a silane coupling agent. The filler may also comprise fillers other than carbon black and silicon dioxide. An explanation for each component that may constitute the filler is as described in the section on the rubber composition for the base tread. (Soot content)

[0228] The recovered carbon black content, based on 100 parts by mass of the rubber component, is, for example, more than 2 parts by mass, preferably more than 3 parts by mass, further preferably more than 5 parts by mass, and even more preferably 10 parts by mass or more. On the other hand, the content is preferably less than 60 parts by mass, further preferably less than 55 parts by mass, and even more preferably less than 50 parts by mass. The total content of the recovered carbon black and other carbon black is, for example, more than 20 parts by mass, preferably more than 25 parts by mass, and even more preferably 30 parts by mass or more, based on 100 parts by mass of the rubber component. On the other hand, the total content is preferably less than 100 parts by mass, further preferably less than 90 parts by mass, and even more preferably less than 80 parts by mass.If the carbon black content is within the ranges described above, sufficient reinforcing properties and good dispersion will be obtained in a rubber, and sufficient rubber strength and fuel efficiency will tend to be achieved. (Silicon dioxide content)

[0229] The explanation given for the rubber composition for the base tread can be similarly applied to a silicon dioxide content, when combined, based on 100 parts by mass of the rubber component. (Content of silane coupling agent)

[0230] The explanation given for the rubber composition for the base tread can be similarly applied to the content of a silane coupling agent, if combined. (Other connecting means)

[0231] The rubber composition preferably includes resin. The explanation given for the rubber composition for the base tread can be applied similarly to descriptions other than those above.

[0232] The explanation for each component, if a tire element is made from a rubber composition that includes recovered carbon black, is as described above, and if the tire element is made from a rubber composition that does not include recovered carbon black, the explanation described above can be applied as replacing the recovered carbon black in the explanation described above with regular carbon black. [Rubber composition for another tire element that forms the tire]

[0233] Regarding a rubber compound that forms a tire element other than the base tread, sidewall, clinch apex, insulation, and inner liner, the explanation given for the rubber compound for the base tread can be applied similarly. (Total amount of styrene in rubber component)

[0234] In the present embodiment, the total amount of styrene in mass percent in the rubber component, contained in each rubber composition described above, is preferably less than 2.0. It is further preferably less than 1.5, more preferably less than 1.0, more preferably less than 0.50, more preferably less than 0.40, more preferably less than 0.30, and most preferably less than 0.20. The total amount of styrene in the rubber component can be 0. Such an amount makes it possible to solve the problem of improving fuel efficiency.

[0235] In the present description, various materials containing carbon atoms (for example, rubber, oil, resin, vulcanization accelerator, antioxidant, surfactant, etc.) can be derived from carbon dioxide in the atmosphere. One method for obtaining these materials from carbon dioxide is to convert carbon dioxide directly, or to convert methane, which is obtained from carbon dioxide through a methanation step. <produktionsverfahren>

[0236] The tire according to the embodiment of the present invention can be produced by a known method. (Production of rubber compound)

[0237] Each of the rubber compositions described above can be produced by a known process. For example, it can be produced by kneading each of the components described above using a rubber kneading device, such as an open roller, a closed-type kneader (Bunbury mixer, kneader, etc.), and the like. The kneading step includes, for example, a basic kneading step of kneading bonding 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 it. Furthermore, the basic kneading step can be subdivided into several steps if desired.Examples of kneading conditions include, for example, a kneading process at a delivery temperature of 150 to 170 °C for 3 to 10 minutes in the basic kneading step and a kneading process at 50 to 110 °C for 1 to 5 minutes in the final kneading step, but they are not particularly limited to these. (Production of tires)

[0238] Each of the rubber compositions obtained above can be extruded into a desired shape of a tire element at an unvulcanized stage to form unvulcanized base tread, sidewall, clinch apex, insulation, inner liner, and the like. The tire according to the present embodiment, together with other tire elements, can be formed on a tire forming machine using at least one element of the base tread, sidewall, clinch apex, insulation, inner liner, and the like thus obtained, by a conventional method to form an unvulcanized tire. This unvulcanized tire can be heated and pressurized (vulcanized) in a vulcanizing machine to obtain a tire. Examples of vulcanization conditions include, for example, a process of vulcanizing at 150 to 200 °C for 5 to 30 minutes, but are not specifically limited to this. <anwendung>

[0239] In this description, the tire can be used for any application, regardless of whether it is a pneumatic or deflated tire, and can be described 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. It is preferably used as a tire for an electric vehicle. Furthermore, a passenger car tire is defined as a tire mounted on a four-wheeled vehicle and refers to one with a maximum load capacity of less than 1400 kg. A heavy-duty tire refers to a tire with a maximum load capacity of 1400 kg or more.An electric vehicle tire is defined as a tire mounted on a four-wheeled vehicle powered by an electric motor whose power source is a secondary battery, such as a lithium-ion battery. The term "electric vehicle" also includes vehicles capable of using a fuel cell as a power source. Furthermore, in this description, "tire" can refer to an all-season tire, a summer tire, or a winter tire, such as a studless tire. EXAMPLES

[0240] Examples considered preferred in implementation (examples) are shown below; however, the scope of protection of the present invention is not limited to examples. Results calculated according to each table based on the following evaluation methods, taking into account a rubber composition and a tire obtained using various chemicals shown below, are indicated as indices in the lower part of each table. <materialien>

[0241] Materials used in examples and comparative examples are described collectively below. IR-based rubber 1: TSR 20 (natural rubber) IR-based rubber 2: SVR-L (natural rubber) BR1: BR730, manufactured by JSR Corporation (cis-rich polybutadiene, cis content: 96 mol%) BR2: BR1250H, manufactured by Zeon Corporation (tin-modified BR, polymerized using lithium as an initiator, cis content: 42 mol%, Mw: 570,000) SBR: SBR1502, manufactured by JSR Corporation (unmodified E-SBR, styrene content: 23.5 wt%, vinyl content: 18 mol%, Tg: -56 °C, Mw: 440,000, not oil-diluted) Butyl-based rubber: Chlorobutyl HT1066, manufactured by Exxon Mobil Corporation (chlorobutyl rubber) Soot 1: Show Black N351H, manufactured by Cabot Japan KK (N2SA: 69 m 2 / g, average primary particle size: 29 nm, ash content: 1.0 wt% or less) Soot 2: Show Black N550, manufactured by Cabot Japan KK (N2SA: 42 m 2 / g, average primary particle size: 38 nm, ash content: 1.0 wt% or less) Soot 3: Show Black N660, manufactured by Cabot Japan KK (N2SA: 35 m 2 / g, average primary particle size: 55 nm, ash content: 1.0 wt% or less) Soot 4: Show Black N330, manufactured by Cabot Japan KK (N2SA: 75 m 2 / g, average primary particle size: 30 nm, ash content: 1.0 wt% or less) Recovered carbon black (rCB): Carbon black obtained from a tire pyrolysis process (ash content: 17% by mass). Oil 1: Diana Process NH-70S, manufactured by Idemitsu Kosan Co., Ltd. (aromatic process oil) Oil 2: PS-32, manufactured by Idemitsu Kosan Co., Ltd. (mineral oil) Resin: Petrotack 100V, manufactured by Tosoh Corporation (C5 / C9 resin) Wax: OZOACE 0355, manufactured by Nippon Seiro Co., Ltd. (paraffin-based) Antioxidant: Nocrac 6e, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine) Zinc oxide: Zinc oxide No. 2, manufactured by Mitsui Mining & Smelting Co., Ltd. Stearic acid: Stearic acid “CAMELLIA”, manufactured by NOF CORPORATION Sulfur: HK-200-5, manufactured by Hosoi Chemical Industry Co., Ltd. (sulfur powder, oil content: 5 wt%) Vulcanization accelerator 1: Nocceler CZ, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-Cyclohexyl-2-benzothiazole sulfenamide) Vulcanization accelerator 2: Nocceler NS, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-tert-Butyl-2-benzothiazolylsulfenamide) Vulcanization accelerator 3: Nocceler DM, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (Di-2-benzothiazolyl disulfide) <Reifen mit Kautschukzusammensetzung für Basislauffläche>

[0242] According to the compound formulations shown in Table 1, using a closed 1.7-liter Banbury mixer, all chemicals other than sulfur and vulcanization accelerator are kneaded for 5 minutes until a discharge temperature of 170 °C is reached to obtain a kneaded product. Next, using an open twin-screw mixer, sulfur and vulcanization accelerator are added to the kneaded product, and the mixture is kneaded for 4 minutes until the temperature reaches 105 °C to obtain an unvulcanized rubber composition.The unvulcanized rubber composition is extruded into a base tread mold using an extruder equipped with a pre-shaped die, which is then joined with other tire elements to form an unvulcanized tire, and the unvulcanized tire is press-vulcanized under a temperature of 170 °C for 12 minutes to produce a test tire (tire size: 175 / 60R18, Wt: 181 mm, Dt: 662 mm, value on the left side in inequality (1): 1901). <Reifen mit Kautschukzusammensetzung für Seitenwand>

[0243] According to the compound formulations shown in Table 2, using a closed 1.7-liter Banbury mixer, all chemicals other than sulfur and vulcanization accelerator are kneaded for 5 minutes until a discharge temperature of 170 °C is reached to obtain a kneaded product. Next, using an open twin-screw mixer, sulfur and vulcanization accelerator are added to the kneaded product, and the mixture is kneaded for 4 minutes until the temperature reaches 105 °C to obtain an unvulcanized rubber composition.The unvulcanized rubber composition is extruded into a sidewall shape using an extruder equipped with a pre-shaped die, which is then joined with other tire elements to form an unvulcanized tire, and the unvulcanized tire is press-vulcanized under a temperature of 170 °C for 12 minutes to produce a test tire (tire size: 155 / 55R18, Wt: 164 mm, Dt: 628 mm, value on the left side in inequality (1): 1888). <Reifen mit Kautschukzusammensetzung für Clinch-Apex>

[0244] According to the compound formulations shown in Table 3, using a closed 1.7-liter Banbury mixer, all chemicals other than sulfur and vulcanization accelerator are kneaded for 5 minutes until a discharge temperature of 170 °C is reached to obtain a kneaded product. Next, using an open twin-screw mixer, sulfur and vulcanization accelerator are added to the kneaded product, and the mixture is kneaded for 4 minutes until the temperature reaches 105 °C to obtain an unvulcanized rubber composition.The unvulcanized rubber composition is extruded into a clinch apex shape using an extruder equipped with a pre-shaped die, which is then joined with other tire elements to form an unvulcanized tire, and the unvulcanized tire is press-vulcanized under a temperature of 170 °C for 12 minutes to produce a test tire (tire size: 155 / 55R18, Wt: 164 mm, Dt: 628 mm, value on the left side in inequality (1): 1888). <Reifen mit Kautschukzusammensetzung für Isolierung>

[0245] According to the compound formulations shown in Table 4, all chemicals other than sulfur and vulcanization accelerator are kneaded for 5 minutes at a discharge temperature of 150 °C using a closed 1.7-liter Banbury mixer. Next, sulfur and vulcanization accelerator are added to the resulting kneaded product, and the mixture is kneaded for 4 minutes using an open roller until the temperature reaches 105 °C to obtain an unvulcanized rubber composition for insulation.The unvulcanized rubber composition for insulation is formed into a sheet shape which is joined together with other tire elements to form an unvulcanized tire, and the unvulcanized tire is press-vulcanized under a condition of 170 °C for 12 minutes to produce a test tire (tire size: 195 / 50R20, Wt: 197 mm, Dt: 703 mm, value on the left side in inequality (1): 1969). <Reifen mit Kautschukzusammensetzung für Innerliner>

[0246] According to the compound formulations shown in Table 5, using a closed 1.7-liter Banbury mixer, all chemicals other than sulfur and vulcanization accelerator are kneaded for 4 minutes until a discharge temperature of 160 °C is reached to obtain a kneaded product. Next, using an open twin-screw mixer, sulfur and vulcanization accelerator are added to the resulting kneaded product, and the mixture is kneaded for 4 minutes until the temperature reaches 80 °C to obtain an unvulcanized rubber composition.The unvulcanized rubber composition is formed into a shape of an inner liner, which is joined together with other tire elements to form an unvulcanized tire, and the unvulcanized tire is press-vulcanized under a condition of 170 °C for 12 minutes to produce each test tire (tire size: 195 / 50R20, Wt: 197 mm, Dt: 703 mm, value on the left side in inequality (1): 1969). <bewertung>

[0247] For each test tire, results evaluated using the assessment procedures described below are described in the corresponding columns of each table described below. (Fuel efficiency)

[0248] A rolling resistance tester measures rolling resistance when each test tire is loaded with 50 percent of its maximum load capacity at an internal pressure of 210 kPa and driven at a speed of 80 km / h. The inverse of this value is expressed as an index, with 100 as the reference. The results show that the higher the numerical value, the lower the rolling resistance and the better the fuel efficiency. Table 1 (Element: Base tread; Tire size: 175 / 60R18) Example comparative example 1-1 1-2 1-3 1-4 1-5 1-1 1-2 1-3 Connection (mass parts) IR-based rubber 1 75 75 75 75 75 75 75 75 BR1 25 25 25 25 25 25 25 25 Soot 1 25 25 13 13 20 30 35 35 rCB 5 5 13 13 5 5 - - Antioxidants 3,0 3,0 3,0 3,0 3,0 3,0 3,0 3,0 öl 1 7,0 7,0 7,0 7,0 5,0 7,0 7,0 7,0 resin - - - - 3,0 - - - wax 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 zinc oxide 3,0 3,0 3,0 3,0 3,0 3,0 3,0 3,0 Stearic acid 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 sulfur 2,5 2,5 2,5 2,7 2,5 2,5 2,5 2,5 Vulcanization accelerator1 0,4 0,4 0,4 0,4 0,4 0,4 0,4 0,4 A (mm) 3,3 2,5 2,5 2,5 3,0 4,0 4,0 3,3 B (Mass parts) 30 30 26 26 35 35 35 35 (Dt 2 / Wt) / (B × A)[inequality (2)] 24,5 32,3 37,2 37,2 23,1 17,3 17,3 21,0 Fuel efficiency index 105 110 115 118 105 100 95 100 Table 2 (Element: Sidewall; Tire size: 155 / 55R18) Example comparative example 2-1 2-2 2-3 2-1 2-2 2-3 Connection (mass parts) IR-based rubber 1 45 45 45 45 45 45 BR2 55 55 55 55 55 55 Soot 2 30 30 15 30 37 37 rCB 7 7 15 7 - - Antioxidants 3,4 3,4 3,4 3,4 3,4 3, 4 Öl 2 4,0 4,0 4,0 4,0 4,0 4, 0 wax 1,0 1,0 1,0 1,0 1,0 1, 0 zinc oxide 4,0 4,0 4,0 4,0 4,0 4, 0 Stearic acid 2,5 2,5 2,5 2,5 2,5 2,5 sulfur 2,3 2,3 2,3 2,3 2,3 2,3 Vulcanization accelerator 2 0,8 0,8 0,8 0,8 0,8 0,8 A (mm) 3,0 2,5 2,5 4,0 4,0 3,0 B (Mass parts) 37 37 30 37 37 37 (Dt 2 / Wt) / (B × A)[inequality (2)] 21,7 26,0 32,1 16,2 16,2 21,7 Fuel efficiency index 102 105 108 100 98 100 Table 3 (Element: Clinch-Apex; Tire size: 155 / 55R18) Example comparative example 3-1 3-2 3-3 3-1 3-2 3-3 Connection (mass parts) IR-based rubber 2 50 50 50 50 50 50 BR1 50 50 50 50 50 50 Soot 2 50 40 57 57 65 58 rCB 8 20 8 8 - - Antioxidants 3, 4 3,4 3, 4 3,4 3, 4 3, 4 Öl 2 8, 0 8,0 8, 0 8,0 8, 0 8, 0 wax 1,5 1,5 1,5 1,5 1,5 1,5 zinc oxide 3,5 3,5 3,5 3,5 3,5 3,5 Stearic acid 3,5 3,5 3,5 3,5 3,5 3,5 sulfur 2,6 2,6 2,6 2,6 2,6 2,6 Vulcanization accelerator 1 2,6 2,6 2,6 2,6 2,6 2,6 A (mm) 2,0 1,8 1,5 2,0 2,0 2,0 B (Mass parts) 58 60 65 65 65 58 (Dt 2 / Wt) / (B × A)[inequality (2)] 20,7 22,3 24,7 18,5 18,5 20,7 Fuel efficiency index 102 105 110 100 98 100 Table 4 (Element: Insulation; Tire size: 195 / 50R20) Example comparative example 4-1 4-2 4-3 4-1 4-2 4-3 Connection (mass parts) IR-based rubber 2 80 80 50 80 80 80 SBR 20 20 50 20 20 20 Soot 3 50 - - 75 85 60 rCB 10 60 60 10 - - Antioxidants - - - - - - Öl 2 6,8 6,8 6,8 6,8 6,8 6,8 wax - - - - - - zinc oxide 2,4 2,4 2,4 2,4 2,4 2,4 Stearic acid 1,0 1,0 1,0 1,0 1,0 1,0 sulfur 1,5 1,5 1,5 1,5 1,5 1,5 Vulcanization accelerator 1 1,5 1,5 1,5 1,5 1,5 1,5 Vulcanization accelerator 3 0,3 0,3 0,3 0,3 0,3 0,3 A (mm) 0,5 0,5 0,5 1,5 1,5 0,5 B (Mass parts) 60 60 60 85 85 60 (Dt 2 / Wt) / (B × A)[inequality (2)] 83,6 83,6 83,6 19,7 19,7 83, 6 Fuel efficiency index 102 108 110 100 98 100 Table 5 (Element: Innerliner; Tire size: 195 / 50R20) Example comparative example 5-1 5-2 5-3 5-1 5-2 5-3 Connection (mass parts) Butyl-based rubber 100 100 100 100 100 100 Soot 3 45 25 20 45 55 55 Soot 4 - 20 15 - - - rCB 10 10 10 10 - - Antioxidants - - - - - - Öl 2 5,0 5,0 5,0 5,0 5,0 5,0 wax - - - - - - zinc oxide 1,0 1,0 1,0 1,0 1,0 1,0 Stearic acid 0,5 0,5 0,5 0,5 0,5 0,5 sulfur 0,5 0,5 0,5 0,5 0,5 0,5 Vulcanization accelerator 3 0,8 0,8 0,8 0,8 0,5 0,5 A (mm) 1,5 1,5 1,5 2,4 2,4 1,5 B (Mass parts) 55 55 45 55 55 55 (Dt 2 / Wt) / (B × A)[inequality (2)] 30,4 30,4 37,2 19,0 19,0 30,4 Fuel efficiency index 105 108 110 100 95 100 <Ausführungsformen> Preferred embodiments are shown below. [1] A tire comprising at least one tire element made of a rubber composition including recovered carbon black, wherein A, B, Wt and Dt simultaneously satisfy the following inequalities (1) and (2) and the right-hand side in inequality (1) is preferably 1750, where A represents a thickness in mm of the tire element, B represents a total content in parts by mass of carbon black contained in the rubber composition, Wt represents a cross-sectional width in mm of the tire and Dt represents an outer diameter in mm of the tire: (π / 4)×(Dt2 / Wt)≥1700, (Dt2 / Wt) / (B×A)>20. [2] The tire of [1], wherein the tire element is at least one tire element selected from a base tread, a sidewall, a clinch apex, an insulation and an inner liner. [3] The tire of [1] or [2], wherein the right-hand side in inequality (1) is preferably 1800, more preferably 1850, still more preferably 1880, still more preferably 1900, still more preferably 1950 and still more preferably 2000. [4] The tire of one of [1] to [3], wherein the right side in inequality (2) is 23, further preferably 25, still more preferably 30, still more preferably 35, still more preferably 40 and still more preferably 50. [5] The tire of one of [1] to [4], where the tire element is a base tread, wherein the rubber composition comprises an isoprene-based rubber and a butadiene rubber, and where the total content of isoprene-based rubber and butadiene rubber is greater than 80% by mass. [6] The tire of one of [1] to [4], where the tire element is a sidewall, wherein the rubber composition comprises an isoprene-based rubber and a butadiene rubber, and where the total content of isoprene-based rubber and butadiene rubber is greater than 80% by mass. [7] The tire of one of [1] to [4], where the tire element is a clinch apex, wherein the rubber composition comprises an isoprene-based rubber and a butadiene rubber, and where the total content of isoprene-based rubber and butadiene rubber is greater than 80% by mass. [8] The tire of one of [1] to [4], where the tire element is an insulator, wherein the rubber composition comprises an isoprene-based rubber and a styrene-butadiene rubber, and where the total content of isoprene-based rubber and styrene-butadiene rubber is greater than 80% by mass. [9] The tire of one of [1] to [4], where the tire element is an inner liner wherein the rubber composition comprises a butyl-based rubber, and where the rubber content is butyl-based and greater than 90% by mass.

[10] The tire of one of [1] to [9], wherein a tread surface of the tire has two or more main circumferential grooves extending in a tire circumferential direction, a pair of shoulder rib sections on an outer side in a tire width direction, separated by a pair of outermost main circumferential grooves located on the outermost sides in the tire width direction below the main circumferential grooves, and intermediate rib sections sandwiched between the pair of shoulder rib sections, and wherein a negative rate of the middle web section is greater than 0% and less than 15%, preferably greater than 2% and less than 14%, further preferably greater than 4% and less than 13%, and even more preferably greater than 6% and less than 12%.

[11] The tire of

[10] , wherein the negative rate of the shoulder rib section is greater than 20%, preferably greater than 23%, more preferably greater than 25%, still more preferably greater than 28% and still more preferably greater than 30%.

[12] The tire of one of [1] to

[11] , wherein a total amount of styrene in mass % in a rubber component included in the rubber composition is less than 2.0, preferably less than 1.5, more preferably less than 1.0, still more preferably less than 0.50, still more preferably less than 0.40, still more preferably less than 0.30 and still more preferably less than 0.20.

[13] The tire of one of [1] to

[12] wherein the content of silicon dioxide contained in the rubber composition is less than 10 parts by mass based on 100 parts by mass of a rubber component.

[14] The tire of one of [1] to

[13] , wherein the rubber composition comprises resin.

[15] The tire of one of [1] to

[14] , which is a tire for an electric vehicle. REFERENCE MARK LIST 1 Base running surface 2 Insulation 3 Innerliner 4 side wall 5 Clinch-Apex 41 outermost main circumferential groove 42 circumferential groove 43 middle bridge section 45 Shoulder strap section CL tire equator plane R rim T1 thickness of base running surface T2 Insulation thickness T3 thickness of inner liner T4 side wall thickness T5 thickness of Clinch-Apex QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] WO 2022 / 074932

[0002] EP 3427975 A

[0118] JP 6856781 B [0118, 0119] EP 3173251 A

[0119] JP 2009-2594 A

[0133] Cited non-patent literature

[0000] Rubber Chemistry and Technology", Vol. 85, No. 3, pages 408 to 449 (2012

[0118] Akita Prefectural University Web Journal B / 2019, vol. 6, pp. 216-222

[0133] < / bewertung> < / materialien> < / anwendung> < / produktionsverfahren> < / kautschukkomponente> < / kautschukkomponente> < / kautschukkomponente> < / kautschukkomponente> < / harz> < / kautschukkomponente> < / kautschukzusammensetzung> < / reifen> < / messverfahren> < / definitionen>

Claims

[1] Tire comprising at least one tire element composed of a rubber composition including recovered carbon black, wherein A, B, Wt and Dt simultaneously satisfy the following inequalities (1) and (2), where A represents a thickness in mm of the tire element, B represents a total carbon black content in parts by mass contained in the rubber composition, Wt represents a cross-sectional width in mm of the tire and Dt represents an outside diameter in mm of the tire: (π / 4)×(Dt2 / Wt)≥1700, (Dt2 / Wt) / (B×A)>20. [2] Tire according to claim 1, wherein the tire element is at least one tire element selected from a base tread, a sidewall, a clinch apex, an insulation and an inner liner. [3] Tires according to claim 1 or 2, wherein the right-hand side in inequality (1) is 1800. [4] Tires according to any one of claims 1 to 3, wherein the right side in inequality (2) is 23. [5] Tires according to any one of claims 1 to 4, where the tire element is a base tread, wherein the rubber composition comprises an isoprene-based rubber and a butadiene rubber, and where the total content of isoprene-based rubber and butadiene rubber is greater than 80% by mass. [6] Tires according to any one of claims 1 to 4, where the tire element is a sidewall, wherein the rubber composition comprises an isoprene-based rubber and a butadiene rubber, and where the total content of isoprene-based rubber and butadiene rubber is greater than 80% by mass. [7] Tires according to any one of claims 1 to 4, where the tire element is a clinch apex, wherein the rubber composition comprises an isoprene-based rubber and a butadiene rubber, and where the total content of isoprene-based rubber and butadiene rubber is greater than 80% by mass. [8] Tires according to any one of claims 1 to 4, where the tire element is an insulator, wherein the rubber composition comprises an isoprene-based rubber and a styrene-butadiene rubber, and where the total content of isoprene-based rubber and styrene-butadiene rubber is greater than 80% by mass. [9] Tires according to any one of claims 1 to 4, where the tire element is an inner liner wherein the rubber composition comprises a butyl-based rubber, and where the rubber content is butyl-based and greater than 90% by mass. [10] Tires according to any one of claims 1 to 9, wherein a tread surface of the tire has two or more main circumferential grooves extending in a tire circumferential direction, a pair of shoulder rib sections on an outer side in a tire width direction, separated by a pair of outermost main circumferential grooves located on the outermost sides in the tire width direction below the main circumferential grooves, and intermediate rib sections sandwiched between the pair of shoulder rib sections, and where a negative rate of the middle bridge section is greater than 0% and less than 15%. [11] Tires according to claim 10, wherein the negative rate of the shoulder rib section is greater than 20%. [12] Tires according to any one of claims 1 to 11, wherein the total amount of styrene in mass % in a rubber component included in the rubber composition is less than 2.

0. [13] Tires according to any one of claims 1 to 12, wherein the silicon dioxide content contained in the rubber composition is less than 10 parts by mass based on 100 parts by mass of a rubber component. [14] Tires according to any one of claims 1 to 13, wherein the rubber composition comprises resin. [15] Tire according to any one of claims 1 to 14, which is a tire for an electric vehicle.

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