Tire

Abstract

Provided is a tire with improved handling stability during high-speed travel. A tire characterized by being a tire having a carcass and a tread, the tread having one or more circumferential grooves, the tread being composed of a rubber composition containing a rubber component, a filler, and a resin component, the rubber component containing an isoprene-based rubber and a styrene butadiene rubber, the content of the isoprene-based rubber in the rubber component being 40% by mass or more, the filler containing silica, the rubber composition containing 100 parts by mass or more of silica per 100 parts by mass of the rubber component, the rubber composition containing 50 parts by mass or more of the resin component, the distance from the radially outermost side of the carcass to the deepest part of the circumferential groove of the tread being set as L (mm), the acetone extract of the rubber composition being set as AE (% by mass), the total content of the filler in the rubber composition per 100 parts by mass of the rubber component being set as F (parts by mass), and (F x AE) / L being greater than 170.

Description

Technical Field

[0001] This invention relates to a tire. Background Technology

[0002] Patent Document 1 describes a tire with a tread made of a rubber composition containing isoprene rubber and silica, wherein the tanδ at 20°C and the tanδ at -20°C are within a specified range. This tire can effectively improve low fuel consumption, wear resistance, handling stability at high speeds, and wet grip at high speeds. [Existing Technical Documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2021-25006 Summary of the Invention [The problem the invention aims to solve]

[0004] When isoprene-based rubbers and styrene-butadiene rubbers are used together, silica tends to accumulate in the styrene-butadiene rubber phase and is difficult to disperse, so there is still room for improvement in the various properties of the tires.

[0005] On the other hand, with the improvement of highways in recent years, long-distance high-speed travel is not uncommon, requiring pneumatic tires to have handling stability at high speeds.

[0006] The purpose of this invention is to provide a tire with improved handling stability at high speeds. [Methods for solving the problem]

[0007] This invention relates to a tire, characterized in that, It is a tire consisting of a carcass and a tread. The tread has one or more circumferential grooves. The tread is composed of a rubber composition containing rubber components, fillers, and resin components. The rubber composition contains isoprene-based rubber and styrene-butadiene rubber. The content of isoprene-based rubber in the rubber component is 40% by mass or more. The filler contains silicon dioxide. Relative to 100 parts by weight of the rubber component, the rubber composition contains at least 100 parts by weight of silica and at least 50 parts by weight of resin component. When the distance from the outermost radial direction of the tire carcass to the deepest part of the circumferential groove of the tread is defined as L (mm), the acetone extraction amount of the rubber composition is defined as AE (mass %), and the total filler content in the rubber composition relative to 100 parts by mass of the rubber component is defined as F (parts by mass), (F×AE) / L is greater than 170. [Invention Effects]

[0008] According to the present invention, a tire with improved handling stability at high speeds is provided. Attached Figure Description

[0009]

【 Figure 1 A cross-sectional view of a tire including the tire rotation axis according to one embodiment of the present invention. [Explanation of Labels in the Attached Image] 1: Fetus 2: Tread 3: Tire tread surface 4: Base tread 5: Belt layer 6: Band layer 7: Zhouxianggou 8: The deepest part of Zhouxiang Ditch CL: Tire Equator L: The distance from the outermost radial side of the tire carcass to the deepest part of the circumferential groove in the tread. Detailed Implementation

[0010] The following describes a tire according to an embodiment of the present invention. A tire is characterized in that it has a carcass and a tread, the tread having one or more circumferential grooves, the tread being composed of a rubber composition containing a rubber component, a filler, and a resin component, the rubber component containing isoprene rubber and styrene-butadiene rubber, the isoprene rubber content in the rubber component being 40% by mass or more, the filler containing silica, and relative to 100 parts by mass of the rubber component, the rubber composition containing 100 parts by mass of silica and 50 parts by mass of resin component, wherein the distance from the outermost radial direction of the carcass to the deepest part of the circumferential groove of the tread is defined as L (mm), the acetone extraction amount of the rubber composition is defined as AE (% by mass), and the total filler content in the rubber composition relative to 100 parts by mass of the rubber component is defined as F (parts by mass), and (F×AE) / L is greater than 170.

[0011] While we do not wish to limit ourselves theoretically, the reasons for the improved handling stability at high speeds in this invention can be considered as follows.

[0012] For example, in the tire of the present invention, (1) by containing isoprene rubber and styrene-butadiene rubber, and wherein the content of isoprene rubber in the rubber composition is 40% by mass or more, an isoprene rubber phase of a certain size or larger is formed in the rubber matrix, creating an interface between it and the styrene-butadiene rubber phase, thereby mitigating the force applied from the road surface during driving, thus contributing to improved handling stability. Furthermore, (2) by containing 100 parts by mass or more of silica relative to 100 parts by mass of the rubber composition, the reinforcing polymer chain effect of silica is easily obtained, thus contributing to improved handling stability at high speeds. (3) by containing 50 parts by mass or more of resin relative to 100 parts by mass of the rubber composition, it contributes to improved handling stability at high speeds. (4) When the distance from the outermost radial side of the tire carcass to the deepest part of the circumferential groove of the tread is set as L (mm), the acetone extraction amount of the rubber composition is set as AE (mass%), and the total content of filler in the rubber composition relative to 100 parts by mass of the rubber component is set as F (parts by mass), (F×AE) / L is greater than 170, which helps to improve the handling stability performance at high speeds. It can be considered that through the synergistic effect of (1) to (4) above, this particularly significant effect of improving the handling stability performance at high speeds can be achieved.

[0013] The rubber composition described above preferably contains 130 or more parts by mass of silicon dioxide relative to 100 parts by mass of the rubber component.

[0014] This is because it can be assumed that the reinforcing polymer chain effect brought by silica can be obtained more easily, thus improving the handling stability at high speeds.

[0015] The content of styrene-butadiene rubber in the above-mentioned rubber components is preferably greater than 40% by mass.

[0016] It can be argued that the effect of mitigating the forces exerted by the road surface during driving is further improved, and the handling stability at high speeds is further enhanced.

[0017] The preferred CTAB specific surface area C of the aforementioned silica is 190 m². 2 / g or more.

[0018] It can be assumed that by making the specific surface area C of CTAB 190m² 2 With a concentration of / g or higher, the number of bonding points between silica and the polymer increases, resulting in a more robust network structure and thus further improving handling stability at high speeds.

[0019] The styrene content of the above-mentioned styrene-butadiene rubber is preferably 20% by mass or more.

[0020] It can be argued that the effect of mitigating the forces exerted by the road surface during driving is further improved, and the handling stability at high speeds is further enhanced.

[0021] The acetone extraction amount AE (mass%) of the above rubber composition is preferably 25.0 or more.

[0022] It can be considered that by making the acetone extraction amount AE (mass%) above 25.0, the road surface following ability is improved, and therefore, in addition to the effects of the present invention, the wet grip performance is further improved.

[0023] The resin composition is preferably selected from at least one of C9 resins, dicyclopentadiene resins, and terpene resins.

[0024] It can be considered that by mixing the above-mentioned resin components, the rubber can be given adhesive force and the road surface can be improved. Therefore, in addition to the effects of the present invention, the wet grip performance is further improved.

[0025] The above-mentioned rubber composition preferably further contains a mercapto-based silane coupling agent.

[0026] It can be concluded that the handling stability at high speeds is further improved through the effect of mercapto-based silane coupling agents.

[0027] The resin composition is preferably a liquid resin.

[0028] The above-mentioned rubber composition preferably contains liquid rubber.

[0029] The above-mentioned rubber composition preferably further contains vegetable oil.

[0030] Preferably, when the acetone extraction amount of the above rubber composition is set as AE (mass%), F×AE is greater than 3500.

[0031] Preferably, when the acetone extraction amount of the above rubber composition is set as AE (mass%), L×AE is greater than 0.30.

[0032] Preferably, the CTAB specific surface area of ​​the above-mentioned silica is set as C(m²). 2 When / g), C / L is greater than 20.

[0033] The maximum load capacity of the above tires is set to W. L When the weight of the above tires is set as G (kg), G / W L Preferably, it is below 0.0170.

[0034] <Definition> "Standard condition" refers to a tire in a standard condition, assembled on a standard rim and filled with air at the standard internal pressure, under no load. Unless otherwise specified, tires in the standard condition should be used.

[0035] "Standard rim" refers to the rim specified for each tire within a standard system that includes the standards upon which the tire is based. For example, it refers to the standard rim with applicable dimensions listed in the JATMA (Japan Automobile Tire Association) Yearbook, the "Measuring Rim" listed in the ETRTO (European Tyre and Rim Technical Organization) Standards Manual, and the "Design Rim" listed in the TRA (Tire and Rim Association, Inc.) Yearbook. These should be referenced in the order of JATMA, ETRTO, and TRA, and if applicable dimensions are available, their standards should be followed. Furthermore, for tires not specified in the aforementioned standards, it refers to the rim with the smallest width among the smallest diameter rims that can be assembled and maintain internal pressure (i.e., no air leakage between the rim and tire).

[0036] "Standard internal pressure" refers to the air pressure specified for each tire within a standard system that includes the standard on which the tire is based. For example, it refers to the maximum value recorded in JATMA's "Maximum Air Pressure," ETRTO's "Inflation Pressure," and TRA's table "Tire Load Limits at Various Cold Inflation Pressures." Similar to the case of standard rims, it is referenced in the order of JATMA, ETRTO, and TRA. If an applicable size is available, its standard is followed. Furthermore, for tires not specified in the aforementioned standards, it refers to the standard internal pressure (250 kPa or higher) of other tire sizes recorded using the aforementioned standard rims as the standard rim. If multiple standard internal pressures of 250 kPa or higher are recorded, the minimum value is used.

[0037] "Regular load" refers to the load specified for each tire within a standard system that includes the standard on which the tire is based. For example, it refers to the maximum value recorded in JATMA's "Maximum Load Capacity," ETRTO's "Load Capacity," and TRA's "Tire Load Limits at Various Cold Inflation Pressures." Similar to the cases of regular rims and regular tire pressures, it is referenced in the order of JATMA, ETRTO, and TRA. If applicable dimensions are available, their standards are followed. However, for tires not specified in the aforementioned standards, the maximum load capacity W will be calculated separately. L Set to normal load.

[0038] Maximum load capacity W L Calculated using the following formula. "V" represents the virtual volume of the tire (mm²). 3 "Dt" represents the tire's outer diameter (mm) under normal conditions, "Ht" represents the tire's cross-sectional height (mm) in the radial direction of the tire section cut by a plane containing the tire's axis of rotation, and "Wt" represents the tire's cross-sectional width (mm) under normal conditions. When the tire's rim diameter is set to R, Ht can be calculated using (Dt-R) / 2. If the tire sidewall has tread blocks or lettering, Wt is a value that ignores these features. Furthermore, the maximum load capacity has the same meaning as the normal load described above.

[0039]

Number 1

[0040] "Tire weight G (kg)" refers to the weight of the tire alone, excluding the rim. On the other hand, if the tire contains components such as sponge, sealant, or sensor components, the weight includes these components.

[0041] The "carcass" is the component that forms the tire's skeleton, and it consists of at least one carcass ply containing carcass cords and rubber sheets covering the carcass cords. Internal components exist on the radially inner side of the carcass. Examples of these internal components include the inner liner and the release liner.

[0042] "Tread" is a component that includes the part that forms the contact surface of the tire. In the case of a tire skeleton made of steel or textile material, such as a belt layer or belt layer reinforcement layer and a carcass layer, which is part of the tire cross section containing the plane of the tire's rotation axis, it refers to a component that is located further outward in the radial direction of the tire than these components.

[0043] A "groove" refers to a recess in the tread of a tire, where the opening width at the tread contact surface is 2.0 mm or more. Recesses with an opening width less than 2.0 mm at the tread contact surface are called "sipes".

[0044] "Circumferential grooves" refer to grooves that extend around the circumference of a tire. Circumferential grooves can extend in a straight line, or in a wavy, sinusoidal, or sawtooth shape.

[0045] "Groove depth" refers to the distance between the end of a straight line connecting the ends of a groove on the tread surface and the lowest point of the groove in the tire's radial direction, based on a tire cross-section in a plane containing the tire's axis of rotation. When the groove depth varies with the tire's width and / or circumferential direction, the maximum value of this straight-line distance is defined as the groove depth.

[0046] "The deepest part of the circumferential groove of the tread" refers to the lowest part of the circumferential groove in the tread, where the distance between the straight line connecting the end of the groove on the tread surface and the lowest part of the groove in the tire's radial direction is the greatest.

[0047] When the tire carcass is composed of multiple carcass plies, "the distance L (mm) from the outermost radial side of the tire carcass to the deepest part of the circumferential groove of the tread" is set as the distance from the outermost radial side of the tire carcass plies to the deepest part of the circumferential groove of the tread.

[0048] "Belt layer" refers to one of the reinforcing layers, consisting of at least one belt layer ply. The multiple belt layer cords constituting the belt layer ply are arranged substantially parallel, with the extension direction of the belt layer cords inclined at more than 10° relative to the tire circumference. The belt layer has an interface on the tire circumference. Here, "substantially parallel" means that the angle difference between the extension direction of each belt layer cord relative to the tire circumference is within ±3°.

[0049] "Belt layer" refers to one of the reinforcing layers, consisting of at least one belt layer ply. The belt layer cords constituting the belt layer ply are arranged in a spiral wound state along the tire circumference, and the extension direction of the belt layer cords is inclined at less than 5° relative to the tire circumference. The belt layer has no joint on the tire circumference.

[0050] "Rubber component of rubber composition" refers to the component that participates in cross-linking within the rubber composition, typically a component with a weight-average molecular weight (Mw) of 10,000 or higher.

[0051] "Plasticizer" refers to a material that imparts plasticity to rubber components; it is a component extracted from rubber compositions using acetone. Plasticizers include those that are liquid at 25°C and those that are solid at 25°C. It excludes waxes and stearic acid, which are commonly used in the tire industry.

[0052] "Plasticizer content" also includes the amount of plasticizer contained in the incremental rubber component, which is pre-increased by plasticizers such as oil, resin components, and liquid rubber. Furthermore, the same applies to the content of oil, resin components, and liquid rubber; for example, when the incremental component is oil, the incremental oil is included in the oil content.

[0053] "Glass transition temperature (Tg) of rubber component" refers to the static glass transition temperature of each rubber component determined by a differential scanning calorimeter (e.g., Q200 manufactured by TA Instruments Japan).

[0054] In this specification, "glass transition temperature Tg (°C) of styrene-butadiene rubber" refers to the glass transition temperature calculated for each type of styrene-butadiene rubber, even when the rubber composition contains two or more types of styrene-butadiene rubber.

[0055] "Acetone Extraction (AE) Amount" is calculated using the following formula, based on JIS K 6229, which involves immersing each vulcanized rubber test piece in acetone for 72 hours to extract soluble components, measuring the mass of each test piece before and after extraction, and then using this formula. Acetone extraction yield (mass%) = {(mass of rubber test piece before extraction - mass of rubber test piece after extraction) / (mass of rubber test piece before extraction)} × 100

[0056] The styrene content was determined by pyrolysis gas chromatography or NMR. 1 H-NMR or 13 The styrene content is calculated using C-NMR. Since component values ​​such as "styrene content" differ from physical properties such as the complex elastic modulus (E*), and therefore have true values ​​independent of the measurement method, it is preferable to use a measurement method with the highest possible accuracy. Furthermore, in this specification, "thermal decomposition gas chromatography" refers to a method in which the sample is heated using a thermal decomposition apparatus, and the components contained in the gas phase generated by this heating are separated using a separation column, and the separated components are analyzed. Styrene content is applicable, for example, to rubber components such as SBR that have repeating units (styrene units) derived from styrene.

[0057] "Styrene content (mass%) of styrene-butadiene rubber" refers to the styrene content (mass%) of styrene-butadiene rubber (SBR). When the rubber composition contains only one type of SBR, it is the styrene content of that SBR. When the rubber composition contains multiple types of SBR, it is calculated by summing the product of the styrene content of each SBR and the amount (mass%) of that SBR when all SBRs are set to 100% by mass.

[0058] For example, when the rubber composition consists of 20% by mass of the first SBR (styrene content: 25% by mass), 30% by mass of the second SBR (styrene content: 27.5% by mass), and 50% by mass of BR, the styrene content of the styrene-butadiene rubber is 26.5% by mass (=(25×40 / 100)+(27.5×60 / 100)).

[0059] "Vinyl content (1,2-bonded butadiene unit weight)" was determined by pyrolysis gas chromatography or NMR. 1 H-NMR or 13 The content of vinyl groups is calculated using C-NMR. Similar to the content of styrene, the true value of vinyl groups exists independently of the measurement method; therefore, it is preferable to use a measurement method with the highest possible accuracy.

[0060] "cis content (cis-1,4-bonded butadiene unit mass)" is determined according to JIS K 6239-2:2017 by infrared absorption spectroscopy or NMR analysis. 1 H-NMR or 13 The values ​​determined by C-NMR are applicable, for example, to rubber components such as BR that have repeating units derived from butadiene. Like the "styrene content," the "cis content" also has a true value that is independent of the measurement method; therefore, it is preferable to use a measurement method with the highest possible accuracy.

[0061] "Weight-average molecular weight (Mw)" is a value determined by gel permeation chromatography (GPC) (e.g., Tosoh GPC-8000 series, detector: differential refractometer, column: Tosoh TSKgel (registered trademark) SuperMultipore HZ-M). It can be calculated from standard polystyrene. For example, it is applicable to SBR, BR, plasticizers, etc.

[0062] The nitrogen adsorption specific surface area (N2SA) of carbon black was determined according to JIS K 6217-2:2017.

[0063] "Nitrogen adsorption specific surface area (N2SA) of silica" is determined by the BET method according to ASTM D3037-93.

[0064] The "CTAB (hexadecyltrimethylammonium bromide) specific surface area C of silica" is determined according to ASTM D3765-92. When the rubber composition contains only one type of silica, the "CTAB specific surface area C" is the CTAB specific surface area of ​​that silica. When the rubber composition contains multiple types of silica, it is calculated by summing the products of the CTAB specific surface areas of each silica and the amount (by mass%) of that silica when all silica is considered to be 100% by mass.

[0065] The "average primary particle size" is calculated by taking photographs of the particles using a transmission or scanning electron microscope and then taking the arithmetic mean of the particle sizes of 400 particles. When the particle shape is spherical, the diameter of the sphere is taken as the particle size; for particles other than spheres, the diameter of the equivalent circle calculated from the microscope image (the positive square root of {4 × (particle area) / π}) is taken as the particle size. The average primary particle size is applicable to materials such as silica and carbon black.

[0066] "The softening point of the resin component" is the temperature at which the ball drops when the softening point specified in JIS K 6220-1:2015 7.7 is measured using a ring and ball softening point measuring device.

[0067] The embodiments will now be described in further detail. The following description is merely illustrative of the invention and is not intended to limit the invention. Furthermore, accompanying drawings are used appropriately for illustration, but these drawings are only examples.

[0068] [tire] The tire involved in this embodiment is a tire having a carcass and a tread, the tread having one or more circumferential grooves, the tread being composed of a specified rubber composition, wherein the distance from the outermost radial side of the carcass to the deepest part of the circumferential groove of the tread is defined as L (mm), the acetone extraction amount of the rubber composition constituting the tread is defined as AE (mass%), and the total content of filler in the rubber composition constituting the tread relative to 100 parts by mass of rubber components is defined as F (parts by mass), and (F×AE) / L is greater than 170.

[0069] The tread according to this embodiment has at least one rubber layer. The structure of the tread is not particularly limited, and it may have two or more rubber layers. For example, it may have two rubber layers: an outer tread surface constituting the tread surface and a base tread adjacent to the radially inner side of the tire on the outer side of the tread surface. The radially inner or outer side of the base rubber layer may further have one or more rubber layers. When the tread has two or more rubber layers, the rubber composition constituting any one of the rubber layers may be the rubber composition according to this embodiment. Preferably, the tread surface is the rubber composition according to this embodiment, and more preferably, all two or more rubber layers are the rubber composition according to this embodiment.

[0070] The tread of this embodiment has one or more circumferential grooves, preferably two or more circumferential grooves, and more preferably three or more circumferential grooves.

[0071] Figure 1 This is a cross-sectional view of the tire involved in this embodiment, including the tire's axis of rotation. Figure 1 In the diagram, the vertical direction is the tire's radial direction, the horizontal direction is the tire's width direction, and the direction perpendicular to the paper is the tire's circumferential direction. Figure 1 The tire has a carcass 1 and a tread 2. Figure 1 In the tire, the tread 2 has a tread running surface 3 and a base tread 4, and the tread 2 has multiple circumferential grooves 7. Figure 1 In this tire, the carcass 1 is composed of a single carcass ply, which has multiple carcass cords and rubber covering the carcass cords. The belt layer 5 is composed of a single belt layer ply, which has multiple belt layer cords and rubber covering the belt layer cords. The belt layer 6 is composed of a single belt layer ply, which has multiple belt layer cords and rubber covering the belt layer cords.

[0072] <The distance L from the outermost radial side of the tire carcass to the deepest part of the circumferential groove in the tread> In this embodiment, the distance L from the outermost radial side of the tire carcass to the deepest part of the circumferential groove in the tread is preferably 6.0 mm or more, more preferably 6.5 mm or more, even more preferably 7.0 mm or more, and even more preferably 8.0 mm or more. Furthermore, the distance L is preferably 12.0 mm or less, more preferably 11.0 mm or less, and even more preferably 10.0 mm or less.

[0073] <Acetone Extraction Amount AE> From the viewpoint of improving the dispersibility of silica, the acetone extraction amount AE (mass%) of the rubber composition constituting the tread is preferably 16.0 or more, more preferably 18.0 or more, further preferably 20.0 or more, even more preferably 22.0 or more, and particularly preferably 25.0 or more. Furthermore, this acetone extraction amount AE (mass%) is preferably 35.0 or less, more preferably 33.0 or less, and even more preferably 31.0 or less. The acetone extraction amount of the rubber composition can be increased by increasing the amount of soluble components mixed in, and decreased by decreasing the amount of soluble components mixed in. Examples of soluble components mixed in the rubber composition include, for example, plasticizers and liquid rubber.

[0074] <F×AE> In the rubber composition constituting the tread, when the total content of filler in the rubber composition relative to 100 parts by mass of the rubber component is defined as F (parts by mass), from the viewpoint of the present invention, F×AE is preferably greater than 2300, more preferably greater than 2500, further preferably greater than 2800, further preferably greater than 3000, further preferably greater than 3200, further preferably greater than 3500, and particularly preferably greater than 3600. On the other hand, there is no particular limitation on the upper limit of F×AE, but it is preferably less than 8000, more preferably less than 7500, and further preferably less than 7000. The total content of filler in the rubber composition relative to 100 parts by mass of the rubber component, F (parts by mass), will be described below.

[0075] <(F×AE) / L> In this embodiment, when the distance from the outermost radial side of the tire carcass to the deepest part of the circumferential groove of the tread is defined as L (mm), the acetone extraction amount of the rubber composition constituting the tread is defined as AE (mass%), and the total filler content in the rubber composition constituting the tread relative to 100 parts by mass of the rubber component is defined as F (parts by mass), (F×AE) / L is greater than 170, preferably greater than 200, more preferably greater than 220, further preferably greater than 250, further preferably greater than 270, further preferably greater than 290, further preferably greater than 310, further preferably greater than 350, further preferably greater than 380, and further preferably greater than 400. Furthermore, there is no particular limitation on the upper limit of (F×AE) / L, but it is preferably less than 1000, more preferably less than 950, and further preferably less than 900. The total filler content F (parts by mass) in the rubber composition relative to 100 parts by mass of the rubber component will be described below.

[0076] <l ae> From the viewpoint of the effectiveness of the present invention, L / AE is preferably greater than 0.28, more preferably greater than 0.30, and even more preferably greater than 0.33. Furthermore, L / AE is preferably less than 0.50, more preferably less than 0.45, and even more preferably less than 0.40.

[0077] <c l> The CTAB specific surface area of ​​the silica contained in the rubber composition specified above is set as C(m²). 2 From the viewpoint of the effectiveness of the present invention, C / L is preferably greater than 20, more preferably greater than 22, and even more preferably greater than 25. Furthermore, C / L is preferably less than 35, more preferably less than 30, and even more preferably less than 28. Regarding the CTAB specific surface area C(m²) of silica... 2 / g), as described below.

[0078] From the viewpoint of better utilizing the effects of the present invention, the maximum load capacity W of the tire involved in this embodiment is... L The maximum load capacity (kg) is preferably 300 or more, more preferably 400 or more, further preferably 450 or more, even more preferably 500 or more, even more preferably 550 or more, and particularly preferably 600 or more. Furthermore, from the viewpoint of better utilizing the effects of the present invention, the maximum load capacity W... L (kg), for example, can be set to below 1300, below 1200, below 1100, below 1000, below 900, below 800, below 700. In addition, the maximum load capacity W... L The volume of the tire can be increased by increasing the virtual volume V of the space occupied by the tire, and vice versa.

[0079] The tire weight G (kg) involved in this embodiment is preferably 6.0 or more, more preferably 6.5 or more, further preferably 7.0 or more, and particularly preferably 7.5 or more. On the other hand, there is no particular limitation on the upper limit of the tire weight G (kg), which is usually 100 or less, for example, it can be set to 80 or less, 60 or less, 40 or less, 20 or less, 15 or less, etc. In addition, the tire weight G can be changed by conventional methods, that is, the tire weight G can be increased by increasing the specific gravity of the tire or increasing the thickness of the various components of the tire, and vice versa.

[0080] From the viewpoint of the effectiveness of this invention, relative to the maximum load capacity W L The ratio of tire weight G (kg) to tire weight G (kg) (G / W) L The G / W ratio is preferably 0.0170 or less, more preferably 0.0160 or less, and even more preferably 0.0150 or less. On the other hand, from the viewpoint of the effectiveness of the present invention, this G / W ratio... L There is no specific limitation on the lower limit value. For example, it can be set to above 0.0110, above 0.0115, above 0.0120, or above 0.0125.

[0081] [Rubber Composition] The rubber composition constituting the tread according to this embodiment (hereinafter, the rubber composition according to this embodiment) will be described. This rubber composition contains a rubber component, a filler, and a resin component. The rubber component contains isoprene rubber and styrene-butadiene rubber, and the isoprene rubber content in the rubber component is 40% by mass or more. The filler contains silica, and the rubber composition contains 100 parts by mass or more of silica relative to 100 parts by mass of the rubber component, and contains 50 parts by mass or more of the resin component.

[0082] <Rubber Composition> The rubber composition according to this embodiment preferably contains diene rubber as a rubber component. As the diene rubber, any substance commonly used in the tire industry can preferably be used. Specifically, examples include isoprene rubber, butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), and acrylonitrile-butadiene rubber (NBR). These diene rubbers can be used alone or in combination of two or more. The diene rubber content of the rubber composition according to this embodiment is preferably 85% by mass or more, more preferably 90% by mass or more, further preferably 95% by mass or more, and particularly preferably 98% by mass or more. Alternatively, the rubber composition may be composed solely of diene rubber.

[0083] The rubber component involved in this embodiment contains isoprene rubber and SBR, preferably isoprene rubber, SBR and BR, and more preferably only isoprene rubber, SBR and BR.

[0084] (Isoprene-based rubber) As isoprene-based rubbers, materials commonly used in the tire industry, such as isoprene rubber (IR) and natural rubber, can be used. Natural rubber, in addition to unmodified natural rubber (NR), includes epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), deproteinized natural rubber (DPNR), high-purity natural rubber, grafted natural rubber, and other modified natural rubbers. These isoprene-based rubbers can be used individually or in combination of two or more.

[0085] As for NR, there are no special restrictions, and commonly used materials in the tire industry can be used, such as SIR20, RSS#3, TSR20, etc.

[0086] From the viewpoint of the effectiveness of the present invention, the content of isoprene-based rubber in the rubber component involved in this embodiment is 40% by mass or more, preferably more than 40% by mass or more, more preferably 45% by mass or more, and even more preferably 50% by mass or more. Furthermore, from the viewpoint of the effectiveness of the present invention, this content is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less.

[0087] (SBR) There are no particular limitations on the type of SBR used; solution polymerization SBR (S-SBR), emulsion polymerization SBR (E-SBR), etc., can be used. Among these, S-SBR is preferred. Furthermore, modified SBRs (modified S-SBR, modified E-SBR), etc., can also be used. Examples of modified SBRs include SBRs whose ends and / or main chain are modified with compounds (modifiers) having the following functional groups; and modified SBRs coupled with tin, silicon compounds, etc. (condensates, substances with branched structures, etc.). Furthermore, hydrides of these SBRs (hydrogenated SBRs), etc., can also be used. These SBRs can be used individually or in combination of two or more.

[0088] The functional groups of the aforementioned modifier are preferably those containing at least one element selected from silicon, nitrogen, and oxygen. Examples of such functional groups include amino, amide, silyl, alkoxysilyl, isocyanate, imino, imidazo, urea, ether, carbonyl, oxycarbonyl, mercapto, thioether, dithioether, sulfonyl, sulfinyl, thiocarbonyl, ammonium, imide, hydrazine, azo, diazo, carboxyl, nitrile, pyridyl, alkoxy (preferably alkoxy with 1 to 6 carbon atoms), hydroxyl, oxygen, epoxy, etc., with amino and / or alkoxysilyl preferred. The amino group is preferably an amino group substituted with 1 to 2 alkyl groups having 1 to 6 carbon atoms. Specific examples of alkoxysilyl compounds include, for example, trimethoxysilyl, triethoxysilyl, triisopropoxysilyl, dimethoxymethylsilyl, diethoxymethylsilyl, dimethylmethoxysilyl, dimethylethoxysilyl, etc.

[0089] As the SBR, both oil-extended and non-oil-extended SBRs can be used. The SBR that can be used in this embodiment can be a commercially available substance from companies such as JSR Corporation, Sumitomo Chemical Co., Ltd., UBE Corporation, Asahi Kasei Corporation, ZSELASTOMERS Corporation, and ARLANXEO Corporation.

[0090] The styrene content of SBR is preferably 10% by mass or more, more preferably 15% by mass or more, even more preferably 20% by mass or more, and even more preferably 22% by mass or more. Furthermore, the styrene content of SBR is preferably 45% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less. The styrene content of SBR is determined by the above-described method. When the rubber composition contains two or more types of styrene-butadiene rubber, the "styrene content of SBR (by mass%)" is taken as a weighted average.

[0091] In this embodiment, from the viewpoint of the effects of the present invention, the glass transition temperature Tg of the SBR is preferably below -60°C, more preferably below -62°C, even more preferably below -65°C, even more preferably below -68°C, and particularly preferably below -70°C. Furthermore, the glass transition temperature Tg of the SBR refers to the glass transition temperature of each SBR measured by the above-described method for "glass transition temperature Tg of rubber components".

[0092] From the viewpoint of ensuring hysteresis loss, the vinyl content of SBR is preferably greater than 5 mol%, more preferably greater than 10 mol%, and even more preferably greater than 15 mol%. Furthermore, from the viewpoint of low fuel consumption performance, the vinyl content of SBR is preferably less than 60 mol%, more preferably less than 50 mol%, and even more preferably less than 40 mol%. In addition, the vinyl content of SBR is determined by the above-described determination method.

[0093] From the viewpoint of the effectiveness of the present invention, the weight-average molecular weight (Mw) of the SBR is preferably greater than 80,000, more preferably greater than 100,000, even more preferably greater than 150,000, and particularly preferably greater than 500,000. Furthermore, from the viewpoint of crosslinking uniformity, Mw is preferably less than 2,000,000, more preferably less than 1,500,000, and even more preferably less than 1,100,000. Moreover, the Mw of the SBR is determined by the above-described measurement method.

[0094] From the viewpoint of the effectiveness of the present invention, the content of SBR in the rubber component is preferably 15% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, even more preferably 40% by mass or more, even more preferably greater than 40% by mass, even more preferably 42% by mass or more, even more preferably 44% by mass or more, even more preferably 45% by mass or more. Furthermore, the content of SBR in the rubber component is preferably 60% by mass or less, more preferably 58% by mass or less, even more preferably 55% by mass or less, even more preferably 53% by mass or less, and particularly preferably 50% by mass or less.

[0095] (BR) There are no particular limitations on the type of BR used. For example, BR with a cis content of less than 50 mol% (low-cis BR), BR with a cis content of more than 90 mol% (high-cis BR), rare earth-based butadiene rubber synthesized with rare earth element catalysts (rare earth-based BR), BR containing syndiotactic polybutadiene crystals (BR containing SPB), and modified BR (high-cis modified BR, low-cis modified BR), etc., commonly used in the tire industry, can be used. These BRs can be used alone or in combination of two or more.

[0096] As a high-cis BR, for example, commercially available materials from companies such as Zeon Corporation, UBE Corporation, and JSR Corporation can be used. By containing a high-cis BR, low-temperature properties and wear resistance can be improved. The cis content of the high-cis BR is preferably greater than 95 mol%, more preferably greater than 96 mol%, and even more preferably greater than 97 mol%. Furthermore, the cis content of the BR is determined by the aforementioned method.

[0097] As a rare earth-based BR synthesized using a rare earth element catalyst, the vinyl content is preferably less than 1.8 mol%, more preferably less than 1.6 mol%, and even more preferably less than 1.5 mol%, with the cis content preferably greater than 95 mol%, more preferably greater than 96 mol%, and even more preferably greater than 97 mol%. For example, commercially available substances from companies such as Lanxess Corporation can be used as a rare earth-based BR.

[0098] Examples of SPB-containing BRs include 1,2-syndiotactic polybutadiene crystals, which are not simply dispersed in the BR, but rather are substances that are chemically bonded to and dispersed with the BR. Commercially available materials such as those from UBE Corporation can be used as SPB-containing BRs.

[0099] As a modified BR, in addition to BRs modified with the same functional groups as those described in the above SBR, modified butadiene rubber (modified BR) with functional groups containing at least one element selected from silicon, nitrogen and oxygen can also be used preferably.

[0100] Other examples of modified BR include tin-modified BR, which is obtained by polymerizing 1,3-butadiene using a lithium initiator and then adding a tin compound, with the ends of the modified BR molecules further bonded by tin-carbon bonds. Furthermore, the modified BR can be either non-hydrogenated or any type of hydrogenated modified BR.

[0101] From the viewpoint of wear resistance, the weight-average molecular weight (Mw) of BR is preferably greater than 300,000, more preferably greater than 350,000, and even more preferably greater than 400,000. Furthermore, from the viewpoint of crosslinking uniformity, it is preferably less than 2,000,000, more preferably less than 1,000,000, and even more preferably less than 500,000. Moreover, Mw can be determined using the methods described above.

[0102] The content of BR in the rubber component is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, even more preferably 7% by mass or more, and particularly preferably 10% by mass or more. Furthermore, the content of BR in the rubber component is preferably less than 20% by mass, more preferably less than 18% by mass or less, and even more preferably less than 16% by mass or less.

[0103] (Other rubber components) Within the scope that does not affect the effects of the present invention, the rubber component may also contain other rubber components besides diene rubbers. As other rubber components besides diene rubbers, crosslinkable rubber components commonly used in the tire industry can be used, such as butyl rubber (IIR), halogenated butyl rubber, ethylene propylene rubber, polynorbornene rubber, silicone rubber, chlorinated polyethylene rubber, fluororubber (FKM), acrylic rubber (ACM), chlorohydrin rubber, and other non-diene rubbers. Furthermore, in addition to the above-mentioned rubber components, known thermoplastic elastomers may be included or excluded. Other rubber components may be used alone or in combination of two or more.

[0104] (Rubber components synthesized from raw materials derived from recycled / biomass) The monomers used as structural units in synthetic rubbers such as IR, SBR, and BR can be substances derived from underground resources such as petroleum and natural gas, or substances recycled from rubber products such as tires or non-rubber products such as polystyrene. There are no particular limitations on the monomers obtained through recycling (recycled monomers), and examples include recycled polyisoprene, recycled butadiene, and recycled aromatic vinyl compounds. Examples of butadiene include 1,2-butadiene and 1,3-butadiene. There are no particular limitations on the aromatic vinyl compounds, and examples include styrene. Preferably, recycled polyisoprene (recycled isoprene), recycled butadiene (recycled butadiene), and / or recycled styrene (recycled styrene) are used as raw materials.

[0105] There are no particular limitations on the manufacturing method of the recycled monomer. For example, it can be synthesized from recycled naphtha obtained by pyrolyzing rubber products such as tires. Furthermore, there are no particular limitations on the manufacturing method of the recycled naphtha. For example, rubber products such as tires can be pyrolyzed under high temperature and pressure, microwave pyrolysis can be used, or extraction can be performed after mechanical crushing.

[0106] Furthermore, the monomers that serve as structural units of polymers such as IR, SBR, and BR can also be derived from biomass. In this specification, biomass refers to substances derived from natural resources such as plants. There are no particular limitations on what constitutes biomass; examples include substances derived from agricultural, forestry, and aquatic products, or sugars, sawdust, plant residues after the extraction of useful components, plant ethanol, and biomass naphtha.

[0107] The term "biomass monomer" is not particularly limited and can include butadiene derived from biomass, aromatic vinyl compounds derived from biomass, etc. Examples of butadiene include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds include styrene, etc. Furthermore, the method of manufacturing biomass monomers is not particularly limited; for example, substances derived from biological and / or chemical and / or physical transformations of plants and animals can be listed. A representative example of biological transformation is microbial fermentation; examples of chemical and / or physical transformations include catalyst-based transformations, high-temperature-based transformations, high-pressure-based transformations, electromagnetic wave-based transformations, supercritical fluid-based transformations, and combinations thereof.

[0108] The term "biomass polymer" is not particularly limited to polymers synthesized from biomass monomer components, but may include examples such as polybutadiene rubber synthesized from butadiene derived from biomass, and aromatic vinyl / butadiene copolymers synthesized from butadiene derived from biomass and / or aromatic vinyl compounds derived from biomass. Examples of such aromatic vinyl / butadiene copolymers include, for instance, styrene-butadiene rubber synthesized from butadiene derived from biomass and / or styrene derived from biomass.

[0109] Whether the polymer's raw material is derived from biomass can be determined by measuring the pMC (percent Modern Carbon) according to ASTM D6866-10. pMC refers to the percentage of modern carbon in the sample. 14 C concentration relative to standard modern carbon (modern standard reference) 14 The C concentration ratio is a value used as an indicator of the proportion of compounds in biomass. The significance of this value is described below.

[0110] One mole of carbon atoms (6.02 × 10⁻⁶) 23 Of these, approximately one trillionth exists, which is about 6.02 × 10⁻⁶. 11 indivual 14 C. 14 The half-life of C is 5730 years. 14 C decreases systematically. Therefore, it is believed that carbon dioxide and other atmospheric substances, after being absorbed and fixed by plants and other organisms, have undergone more than 226,000 years of aging in fossil fuels such as coal, oil, and natural gas. The carbon dioxide contained in these fossil fuels during their initial fixation... 14 All carbon (C) decays. Therefore, in the 21st century, fossil fuels such as coal, oil, and natural gas contain absolutely no carbon. 14 Therefore, the chemicals produced using these fossil fuels as raw materials also contain absolutely no carbon (C). 14 C element.

[0111] on the other hand, 14 C is continuously generated through nuclear reactions in the atmosphere via cosmic rays. Therefore, 14 In Earth's atmosphere, the reduction of carbon based on radioactive decay and the generation based on nuclear reactions reach equilibrium. 14 The amount of C is constant. Therefore, in the current environment, the matter originating from biomass resources in the material cycle... 14 The C concentration, as described above, is approximately 1 × 10⁻⁶ relative to all C atoms. -12 These are values ​​approximately in mol%. Therefore, by using the differences between these values, the proportion of biomass in a compound can be calculated.

[0112] Typically, the 14 C was determined as described below. Accelerator mass spectrometry based on a tandem accelerator was used for the determination. 13 C concentration ( 13 C / 12 C) 14 C concentration ( 14 C / 12 C) Determination. During the determination, as... 14 The standard for C concentration in modern carbon is based on the carbon cycling in nature as of 1950. 14 C concentration. As a specific standard substance, the oxalic acid standard provided by NIST (National Institute of Standards and Technology) was used. The radioactivity of carbon in this oxalic acid (carbon content per gram of carbon) was determined. 14 The radioactivity intensity of carbon (C) is classified according to its carbon isotopes. 13 The C-correction is a fixed value, using the value with attenuation correction applied from 1950 to the date of measurement as the standard. 14 The C concentration value (100%) is used. The ratio of the actual measured value of the sample to this value is the pMC value.

[0113] Therefore, if the rubber is made from 100% biomass-derived materials, then despite regional differences, it is expected to have a value of around 110 pMC, as it is generally not 100 pMC under normal conditions. On the other hand, for chemicals derived from fossil fuels such as petroleum, the measured... 14 At C concentrations, the value is around 0 pMC (e.g., 0.3 pMC). This value corresponds to 0% of the biomass ratio mentioned above.

[0114] In summary, using rubber and other materials with high pMC values, i.e., rubber and other materials with a high proportion of biomass, in rubber compositions is preferred from an environmental protection perspective.

[0115] <packing> The rubber composition according to this embodiment contains silica as a filler, and preferably contains silica and carbon black. Alternatively, the filler may be composed solely of carbon black and silica.

[0116] (Silicon dioxide) There are no particular limitations on the silica used; for example, silica commonly used in the tire industry, such as silica prepared by a dry process (anhydrous silica) or silica prepared by a wet process (hydrated silica), can be used. There are also no particular limitations on the raw materials used for silica; for example, it can be derived from minerals such as quartz, or from biological sources such as rice husks (e.g., silica made from biomass materials such as rice husks), or silica recovered from silica-containing products. However, hydrated silica prepared by a wet process is preferred due to its higher silanol group content. These silicas can be used individually or in combination of two or more types.

[0117] Silica obtained from biomass materials, for example, can be extracted from rice husk ash obtained by burning rice husks using sodium hydroxide solution. The silicate is then reacted with sulfuric acid in the same way as conventional wet silica to form silica precipitate, which is then filtered, washed with water, dried, and pulverized.

[0118] Silica recovered from products containing silica can be, for example, silica recovered from products containing silica such as electronic components like semiconductors, tires, desiccants, and filter materials such as diatomaceous earth. Furthermore, the method of recovery is not particularly limited, and examples include pyrolysis and electromagnetic wave-based pyrolysis. Of these, silica recovered from electronic components like semiconductors or tires is preferred.

[0119] If silica crystallizes, it becomes insoluble in water and cannot utilize the silicic acid that is its component. By managing the combustion temperature and combustion time, the crystallization of silica in rice husk ash can be suppressed (see Japanese Patent Application Publication No. 2009-2594, Akita Prefectural University Online Journal B, 2019, vol.6, pp.216-222, etc.).

[0120] Amorphous silica extracted from rice husks can be obtained from commercially available materials such as those from Wilmar.

[0121] From the viewpoint of the effectiveness of the present invention, the preferred CTAB specific surface area C of silicon dioxide is 110 m². 2 / g or more, preferably 140m 2 / g or more, preferably 170m 2 / g or more, preferably 190m 2 / g or more, especially preferably 200mg 2 / g or more. Furthermore, the specific surface area C of this CTAB is more preferably 300m². 2 / g or less, more preferably 280m 2 / g or less, more preferably 260m 2 / g or less. Furthermore, the CTAB content of silica was determined using the methods described above.

[0122] From the viewpoint of the effectiveness of the present invention, the nitrogen adsorption specific surface area (N2SA) of silica is preferably greater than 110 m². 2 / g, more preferably greater than 130m 2 / g, more preferably greater than 150m 2 / g, more preferably greater than 170m 2 / g, more preferably greater than 190m 2 / g, particularly preferably greater than 210m 2 / g. Furthermore, the N2SA is preferably less than 350m. 2 / g, more preferably less than 320m 2 / g, further preferably less than 280m 2 / g. Furthermore, the N2SA content of silica was determined using the method described above.

[0123] From the viewpoint of the effectiveness of the present invention, the average primary particle size of silica is preferably greater than 8 nm, more preferably greater than 10 nm, and even more preferably greater than 12 nm. Furthermore, this average primary particle size is preferably less than 20 nm, more preferably less than 19 nm, even more preferably less than 18 nm, even more preferably less than 17 nm, and particularly preferably less than 16 nm. Moreover, the average primary particle size of silica is determined by the above-described measurement method.

[0124] From the viewpoint of the effects of the present invention, the content of silica relative to 100 parts by mass of rubber component is 100 parts by mass or more, preferably 110 parts by mass or more, more preferably 120 parts by mass or more, more preferably 130 parts by mass or more, and particularly preferably 135 parts by mass or more. Furthermore, from the viewpoint of compatibility with isoprene-based rubbers, this content is preferably 200 parts by mass or less, more preferably 190 parts by mass or less, and even more preferably 180 parts by mass or less.

[0125] From the viewpoint of the effects of the present invention, the silica content in the filler is preferably 55% by mass or more, more preferably 65% ​​by mass or more, even more preferably 75% by mass or more, even more preferably 85% by mass or more, and particularly preferably 90% by mass or more. Furthermore, from the viewpoint of wear resistance, it is preferably 99% by mass or less, more preferably 97% by mass or less, and even more preferably 95% by mass or less.

[0126] (Carbon black) As for carbon black, there are no particular limitations; examples include N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, and N762. The raw materials for carbon black can be biomass materials such as lignin and vegetable oil, or thermal cracking oil obtained by pyrolysis of waste tires. Furthermore, carbon black can be manufactured using combustion-based methods such as the furnace method, hydrothermal carbonization (HTC) methods, or methane thermal cracking methods such as the thermal cracking carbon black method. Commercially available products include those from Asahi Carbon Co., Ltd., Cabot Japan Co., Ltd., Tokai Carbon Co., Ltd., Mitsubishi Chemical Co., Ltd., Lion Corporation, Nippon Steel Carbon Black Co., Ltd., Columbia Carbon Co., Ltd., etc. These carbon blacks can be used individually or in combination of two or more types.

[0127] In addition to the above, from the perspective of life cycle assessment, recycled carbon black, which is produced by thermally cracking and refining carbon black made from biomass materials such as lignin and carbon black-containing products such as tires, can also be used as carbon black, in addition to the above.

[0128] In this specification, "recycled carbon black" refers to carbon black obtained by pulverizing used products such as tires that contain carbon black, and then burning the pulverized material. Specifically, it refers to carbon black from which, when oxidized and burned in air by heating using the thermogravimetric determination method based on JIS K 6226-2:2003, the proportion of the non-combustible component (ash content) is 13% by mass or more. In other words, recycled carbon black has a carbon content of 87% by mass or less based on the weight loss from the aforementioned oxidative combustion. Recycled carbon black is sometimes also represented as rCB.

[0129] Recycled carbon black can be obtained from the pyrolysis process of used pneumatic tires. For example, European Patent Application Publication No. 3427975 describes, "Rubber Chemistry and Technology", Vol. 85, No. 3, pp. 408-449 (2012), especially pp. 438, 440, 442, which mentions that it is obtained by removing oxygen and then pyrolyzing organic materials at 550-800°C, or by vacuum pyrolysis at a relatively low temperature (

[0027] ). The carbon black obtained by such a pyrolysis process, as mentioned in

[0004] of Patent No. 6856781, is usually a regenerated carbon black lacking functional groups on its surface (Comparison of surface morphology and chemical properties of pyrolysis carbon black and commercially available carbon black, Powder Technology 160 (2005) 190-193).

[0130] Recycled carbon black can be carbon black lacking functional groups on its surface, or it can be carbon black that has been treated to contain functional groups on its surface. The treatment to contain functional groups on the surface of recycled carbon black can be carried out by conventional methods. For example, in European Patent Application Publication No. 3173251, carbon black containing hydroxyl and / or carboxyl groups on its surface is obtained by treating carbon black obtained from a pyrolysis process with potassium permanganate under acidic conditions. Furthermore, in Patent No. 6856781, carbon black obtained from a pyrolysis process is treated with an amino acid compound containing at least one thiol or disulfide group to obtain carbon black with an activated surface. The recycled carbon black involved in this embodiment includes these carbon blacks treated to contain functional groups on their surface.

[0131] Recycled carbon black can be made from commercially available materials such as Strable Green Carbon and LD Carbon.

[0132] From a reinforcing perspective, the nitrogen adsorption specific surface area (N2SA) of carbon black is preferably greater than 70 m². 2 / g, more preferably greater than 90m 2 / g, more preferably greater than 110m 2 / g, particularly preferably greater than 130m 2 / g. Furthermore, from the viewpoint of exothermic properties and processability, a value of less than 250m is preferred. 2 / g, more preferably less than 220m 2 / g, more preferably less than 190m 2 / g. Furthermore, the N2SA of carbon black was determined using the method described above.

[0133] The average primary particle size of the carbon black is preferably less than 35 nm, more preferably less than 30 nm, even more preferably less than 27 nm, even more preferably less than 23 nm, and particularly preferably less than 19 nm. Furthermore, the average primary particle size is preferably greater than 8 nm, more preferably greater than 10 nm, even more preferably greater than 12 nm, and particularly preferably greater than 14 nm. The average primary particle size of the carbon black is determined by the method described above.

[0134] From the viewpoint of wear resistance, the carbon black content relative to 100 parts by mass of the rubber component is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, and particularly preferably 7 parts by mass or more. Furthermore, this 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, even more preferably less than 20 parts by mass, and particularly preferably less than 15 parts by mass.

[0135] (Other fillers) The filler may also contain fillers other than silica and carbon black. There are no particular limitations on these other fillers; for example, aluminum hydroxide, calcium carbonate, bauxite, clay, talc, and other substances commonly used in the tire industry can be mixed in. These other fillers can be used individually or in combination of two or more.

[0136] In this embodiment, the total filler content F in the rubber composition relative to 100 parts by mass of the rubber component is 100 parts by mass or more, preferably 120 parts by mass or more, more preferably 130 parts by mass or more, even more preferably 140 parts by mass or more, even more preferably 150 parts by mass or more, even more preferably 155 parts by mass or more, and even more preferably 160 parts by mass or more. Furthermore, this content F is preferably 200 parts by mass or less, more preferably 195 parts by mass or less, and even more preferably 190 parts by mass or less.

[0137] <Silane Coupling Agent> Silica is preferably used in combination with a silane coupling agent. There are no particular limitations on the silane coupling agent; any silane coupling agent conventionally used in the tire industry in combination with silica can be used. However, for the purpose of obtaining the desired effect more preferably, one or more silane coupling agents selected from sulfide-based silane coupling agents and mercapto-based silane coupling agents are preferred, and mercapto-based silane coupling agents are more preferred.

[0138] Examples of sulfide-based silane coupling agents include, for example, bis(3-triethoxysilylpropyl) disulfide and bis(3-triethoxysilylpropyl) tetrasulfide. These sulfide-based silane coupling agents can be used alone or in combination of two or more.

[0139] In this specification, mercapto-based silane coupling agents refer to silane coupling agents having a mercapto group and silane coupling agents with a structure in which the mercapto group is protected by a protecting group. There are no particular limitations on mercapto-based silane coupling agents; for example, compounds having a mercapto group represented by formula (2), compounds with a mercapto group protected by an ester group represented by formula (3), and compounds containing a bonding unit A represented by formula (4) and / or a bonding unit B represented by formula (5) are examples. Among these, compounds represented by formula (3) or compounds containing a bonding unit A represented by formula (4) and / or a bonding unit B represented by formula (5) are preferred for better application of the present invention; compounds represented by formula (3) are more preferred. These mercapto-based silane coupling agents can be used alone or in combination of two or more.

Chemical Formula 1

Chemical Formula 3

[0140] Examples of compounds represented by formula (2) include 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, or compounds represented by formula (6) below. One of these may be used alone, or two or more may be used together. [Chemical Formula 5]

[0141] Examples of compounds represented by formula (3) include 3-octanoylthio-1-propyltriethoxysilane, 3-hexanoylthio-1-propyltriethoxysilane, and 3-octanoylthio-1-propyltrimethoxysilane.

[0142] Compounds containing bonding unit A represented by formula (4) and / or bonding unit B represented by formula (5) can suppress viscosity rise during processing compared to sulfide-based silane coupling agents such as bis(3-triethoxysilylpropyl)tetrasulfide. Therefore, it can be considered that the dispersibility of silica is improved, and the low-burning performance, wet grip, and elongation at break are further enhanced. This is likely because the sulfide portion of bonding unit A is a CSC bond, thus exhibiting greater thermal stability and less Mooney viscosity rise compared to tetrasulfides and disulfides.

[0143] From the viewpoint of suppressing viscosity increase during processing, the content of bonding unit A is preferably 30 to 99 mol%, more preferably 50 to 90 mol%. Furthermore, the content of bonding unit B is preferably 1 to 70 mol%, more preferably 5 to 65 mol%, and even more preferably 10 to 55 mol%. In addition, the total content of bonding units A and B is preferably 95 mol% or more, more preferably 98 mol% or more, and particularly preferably 100 mol%. Furthermore, the content of bonding units A and B also includes the amount when bonding units A and B are located at the end of the silane coupling agent. The morphology of bonding units A and B at the end of the silane coupling agent is not particularly limited, as long as they are formed in the units corresponding to formulas (4) and (5) representing bonding units A and B.

[0144] In a compound comprising bonding unit A represented by formula (4) and bonding unit B represented by formula (5), the total number of repetitions (x+y) of bonding unit A and bonding unit B is preferably in the range of 3 to 300. Within this range, due to the -C7H of bonding unit A... 15 The mercaptosilane covering the bonding unit B thus ensures good reactivity with silica and rubber components while suppressing the shortening of scorch time.

[0145] Compounds comprising bonding unit A represented by formula (4) and / or bonding unit B represented by formula (5) are, for example, NXT-Z30, NXT-Z45, NXT-Z60, NXT-Z100, etc. manufactured by Momentive. These can be used alone or in combination of two or more.

[0146] Silane coupling agents other than sulfide-based and mercapto-based silane coupling agents are not particularly limited. Examples include vinyl-based silane coupling agents such as vinyltriethoxysilane and vinyltrimethoxysilane; amino-based silane coupling agents such as 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, and 3-(2-aminoethyl)aminopropyltriethoxysilane; glycidyloxy-based silane coupling agents such as γ-glycidyloxypropyltriethoxysilane and γ-glycidyloxypropyltrimethoxysilane; nitro-based silane coupling agents such as 3-nitropropyltrimethoxysilane and 3-nitropropyltriethoxysilane; and chloro-based silane coupling agents such as 3-chloropropyltrimethoxysilane and 3-chloropropyltriethoxysilane. These other silane coupling agents can be used alone or in combination of two or more. As one of the silane coupling agents listed above, for example, silane coupling agents manufactured and sold by Momentive Corporation, Evonik Industries, etc., can be used.

[0147] From the viewpoint of improving the dispersibility of silica, the content of the silane coupling agent (preferably one or more silane coupling agents selected from sulfide-based silane coupling agents and mercapto-based silane coupling agents) relative to 100 parts by mass of silica is preferably 1.0 parts by mass or more, more preferably 3.0 parts by mass or more, and even more preferably 5.0 parts by mass or more. Furthermore, from the viewpoint of cost and processability, it is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and even more preferably 12 parts by mass or less.

[0148] <Plasticizer> Plasticizers refer to materials that impart plasticity to rubber components, encompassing both liquid plasticizers at 25°C and solid plasticizers at 25°C. Examples of plasticizers include resin components, oils, liquid rubber, and ester-based plasticizers. These plasticizers can be derived from mineral resources such as petroleum and natural gas, biomass, or petroleum naphtha recovered from rubber and non-rubber products. Furthermore, low-molecular-weight hydrocarbon components obtained through the thermal cracking and extraction of used tires and products containing various components can also be used as plasticizers. The rubber composition according to this embodiment preferably contains a resin component as a plasticizer. The resin component preferably contains at least one selected from C9-based resins, dicyclopentadiene-based resins, and terpene-based resins; the presence of a liquid resin is also preferred. Furthermore, the rubber composition according to this embodiment preferably contains liquid rubber and, more preferably, vegetable oil. A single plasticizer or two or more plasticizers can be used in combination.

[0149] (Resin composition) The rubber composition according to this embodiment can also be used in combination with a resin component. In this embodiment, the resin component that can be used is not particularly limited, and resins commonly used in the tire industry can be used. For example, C9 resins, C5 resins, C5C9 resins, dicyclopentadiene resins, aromatic vinyl resins, coumarone resins, indene resins, terpene resins, rosin resins, phenolic resins, etc. can be cited. These resin components can be used individually or in combination of two or more. Each resin component can also be used individually or in combination of two or more.

[0150] <<C9 resin>> "C9 resin" refers to a resin obtained by polymerizing a C9 fraction, which can be a polymer obtained by homopolymerizing a C9 fraction 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. In addition, the C9 resin can also be a hydrogenated product or a modified product thereof. As the C9 fraction, for example, petroleum fractions equivalent to 8 to 10 carbon atoms such as vinyltoluene, alkylstyrene, coumarone, indene, methylindene, and dicyclopentadiene can be cited. As the C9 resin, for example, commercially available substances from BASF, Zeon Corporation of Japan, ENEOS Corporation, etc. can be used.

[0151] 《C5 resin》 "C5 resin" refers to a resin obtained by polymerizing a C5 fraction, which can also be a hydrogenated product or a modified product thereof. As the C5 fraction other than dicyclopentadiene, for example, petroleum fractions equivalent to 4 to 5 carbon atoms such as cyclopentadiene, isoprene, piperylene, 2-methyl-1-butene, 2-methyl-2-butene, and 1-pentene can be cited. As the C5 resin, for example, commercially available substances from STRUKTOL, Zeon Corporation of Japan, ENEOS Corporation, etc. can be used.

[0152] <<C5C9 resin》 "C5C9 resin" refers to a resin obtained by copolymerizing the above C5 fraction with the above C9 fraction, which can also be a hydrogenated product or a modified product thereof. As the C5C9 petroleum resin, for example, commercially available substances from Tosoh Corporation, LUHUA Company, etc. can be used.

[0153] <<Dicyclopentadiene resin>> "Dicyclopentadiene-based resin" refers to a resin containing cyclopentadiene (CPD) and / or dicyclopentadiene (DCPD) as the most abundant monomeric component, or their hydrogenated or modified products. As a dicyclopentadiene-based resin, polymers polymerized solely with dicyclopentadiene as a monomer are preferred, as are copolymers (DCPD / C9 resin) copolymerized with the aforementioned C9 fraction. As a dicyclopentadiene-based resin, commercially available substances from ExxonMobil, ENEOS Corporation, Zeon Corporation of Japan, Maruzen Petrochemical Co., Ltd., etc., can be used.

[0154] <<Aromatic Vinyl Resins<< "Aromatic vinyl resin" refers to a resin containing aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene, and p-chlorostyrene as the most abundant monomer component, or their hydrogenated or modified products. For economic reasons, ease of processing, and excellent exothermic properties, homopolymers of α-methylstyrene or styrene, or copolymers of α-methylstyrene and styrene, are preferred as aromatic vinyl resins, with copolymers of α-methylstyrene and styrene being more preferred. For example, commercially available substances from companies such as Kraton, Eastman Chemical Company, and Mitsui Chemicals Co., Ltd. can be used as aromatic vinyl resins.

[0155] Coumarin-based resins "Coumarone-based resins" refer to resins containing coumarone as a monomer, or their hydrogenated or modified products. Examples of coumarone-based resins include, for instance, coumarone resins made from polymers containing only coumarone as a monomer, coumarone / indene resins made from copolymers of coumarone and indene as monomers, and coumarone / indene / styrene resins made from copolymers of coumarone, indene, and styrene as monomers. Commercially available substances from Rutgers Corporation, Nippon Paint Co., Ltd., and Mitsui Chemicals Co., Ltd., can be used as coumarone-based resins.

[0156] <<Indene Resins>> "Indene-based resin" refers to resins containing indene as a monomer, or their hydrogenated or modified products. Examples of preferred indene-based resins include coumarone / indene resins, copolymers of coumarone and indene as monomers, and coumarone / indene / styrene resins, copolymers of coumarone, indene, and styrene as monomers. Commercially available indene-based resins, such as those from Rutgers Corporation, Nippon Paint Co., Ltd., and Mitsui Chemicals Co., Ltd., can also be used.

[0157] Terpene Resins "Terpene-based resin" refers to a resin containing terpene compounds such as α-pinene, β-pinene, limonene, and dipentene as monomeric components, or their hydrogenated or modified products. Examples of terpene-based resins include, for instance, polyterpene resins, polymers containing only one or more of the aforementioned terpene compounds as monomeric components; aromatic-modified terpene resins, copolymers containing the aforementioned terpene compounds and aromatic compounds as monomeric components; and terpene-phenol resins, copolymers containing the aforementioned terpene compounds and phenolic compounds as monomeric components. Examples of aromatic compounds that are monomeric components of aromatic-modified terpene resins include styrene, α-methylstyrene, vinyltoluene, and divinyltoluene. Examples of phenolic compounds that are monomeric components of terpene-phenol resins include phenol, bisphenol A, cresol, and xylenol. For example, commercially available substances from companies such as Yasuhara Chemical Co., Ltd., Arakawa Chemical Industry Co., Ltd., and Nippon Terpene Chemical Co., Ltd. can be used as terpene-based resins.

[0158] Rosin-based resins "Rosin-based resin" refers to resins containing abietic acid compounds such as abietic acid, neoabietic acid, palustric acid, and isopimaric acid, or their hydrogenated or modified products. There are no particular limitations on the definition of a rosin-based resin; examples include natural rosin resin and rosin-modified resins modified by hydrogenation, disproportionation, dimerization, esterification, etc. For instance, commercially available substances from companies such as Halima Chemicals Co., Ltd., Arakawa Chemical Industry Co., Ltd., and IREC Co., Ltd. can be used as rosin-based resins.

[0159] Phenolic Resins "Phenolic resins" refer to resins containing phenolic compounds such as phenol and cresol as monomers, or their hydrogenated or modified products. There are no particular limitations on phenolic resins; examples include phenol-formaldehyde resins, alkylphenol-formaldehyde resins, alkylphenol-acetylene resins, oil-modified phenol-formaldehyde resins, and terpene phenolic resins. For example, commercially available substances from companies such as Sumitomo Bakelite Co., Ltd., DIC Co., Ltd., and Asahi Organic Materials Co., Ltd. can be used as phenolic resins.

[0160] Liquid Resin The resin component can also be a liquid resin that is liquid at 25°C. There are no particular limitations on the type of liquid resin; examples include liquid aromatic vinyl resins, liquid C9 resins, liquid C5C9 resins, and liquid coumarone / indene resins. These liquid resins can be used alone or in combination of two or more.

[0161] The weight-average molecular weight (Mw) of the liquid resin is typically less than 10,000, preferably 9,000 or less, more preferably 6,000 or less, and even more preferably 4,500 or less. Furthermore, the Mw of the liquid resin is preferably 100 or more, more preferably 500 or more, even more preferably 1,000 or more, even more preferably 1,500 or more, and particularly preferably 2,000 or more.

[0162] From the viewpoint of wet grip performance, the softening point of the resin component is preferably 60°C or higher, more preferably 70°C or higher, and even more preferably 80°C or higher. Furthermore, from the viewpoint of processability and improving the dispersibility of the rubber component and filler, it is preferably 150°C or lower, more preferably 140°C or lower, and even more preferably 130°C or lower. The softening point of the resin component is determined by the above-described method.

[0163] The content of resin component relative to 100 parts by weight of rubber component (the total amount when multiple resin components are used together) is 50 parts by weight or more, preferably 55 parts by weight or more, and more preferably 60 parts by weight or more. On the other hand, from the viewpoint of suppressing heat generation, this content is preferably 100 parts by weight or less, more preferably 90 parts by weight or less, and even more preferably 85 parts by weight or less.

[0164] The total content of C9 resin, dicyclopentadiene resin, and terpene resin relative to 100 parts by weight of the rubber component is preferably 20 parts by weight or more, more preferably 30 parts by weight or more, even more preferably 40 parts by weight or more, even more preferably 50 parts by weight or more, and particularly preferably 55 parts by weight or more. On the other hand, from the viewpoint of suppressing heat generation, this content is preferably 100 parts by weight or less, more preferably 90 parts by weight or less, and even more preferably 80 parts by weight or less.

[0165] (Oil) Examples of oils include mineral oils, vegetable oils, and animal oils. Furthermore, from a life cycle assessment perspective, waste oil from rubber mixers or engines, or refined waste cooking oil from restaurants, can also be used. One type of oil can be used alone, or two or more can be used in combination.

[0166] In this specification, mineral oil refers to oil derived from mineral resources such as petroleum and natural gas. Examples of mineral oils include paraffinic oils, naphthenic oils, and aromatic oils. Specific examples of mineral oils include MES (Mild Extract Solvated), DAE (Distillate Aromatic Extract), TDAE (Treated Distillate Aromatic Extract), TRAE (Treated Residual Aromatic Extract), and RAE (Residual Aromatic Extract). Furthermore, due to environmental measures, oils with lower polycyclic aromatic compounds (PCA) content may also be used. Examples of low PCA content oils include MES, TDAE, and heavy naphthenic oils. Mineral oils can be used alone or in combination of two or more types.

[0167] In this instruction manual, "vegetable oil" refers to, for example, flaxseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice bran oil, tall oil, sesame oil, perilla seed oil, castor oil, tung oil, pine oil, pine tar, sunflower seed oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, and beeswax. Furthermore, as vegetable oils, refined oils (salad oil, etc.) derived from the above oils can also be included, as well as transesterified oils, hydrogenated oils, thermally polymerized oils, oxidized polymerized oils, and waste edible oils recovered from use as cooking oils. In addition, vegetable oils can be liquid or solid at 25°C. One type of vegetable oil can be used alone, or two or more can be used in combination.

[0168] The vegetable oil involved in this embodiment preferably contains acylglycerol, and more preferably contains triacylglycerol. Furthermore, in this specification, acylglycerol refers to a compound in which the hydroxyl group of glycerol forms an ester bond with a fatty acid. There is no particular limitation on the type of acylglycerol; it can be any one of 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, or triacylglycerol. Further, acylglycerol can be a monomer, a dimer, or a polymer of more than one trimer. Moreover, acylglycerols of more than one trimer can be obtained by thermal polymerization, oxidative polymerization, etc. Furthermore, acylglycerol can be liquid or solid at 25°C.

[0169] There is no particular limitation on the method for confirming whether a rubber composition contains acylglycerol; it can be achieved through... 1 Confirmed by ¹H-NMR determination. For example, a rubber composition containing triacylglycerol was impregnated in deuterated chloroform at 25°C for 24 hours, and after removing the rubber composition, the determination was performed at room temperature. 1 In H-NMR, with the tetramethylsilane (TMS) signal set to 0.00 ppm, signals were observed around 5.26 ppm, 4.28 ppm, and 4.15 ppm. It is speculated that these signals originate from hydrogen atoms bonded to the carbon atom adjacent to the oxygen atom of the ester group. Furthermore, "around" in this paragraph refers to a range of ±0.10 ppm.

[0170] The fatty acids mentioned above are not specifically limited and can be either unsaturated or saturated fatty acids. Examples of unsaturated fatty acids include monounsaturated fatty acids such as oleic acid, and polyunsaturated fatty acids such as linoleic acid and linolenic acid. Examples of saturated fatty acids include butyric acid and lauric acid.

[0171] Among these, fatty acids with fewer double bonds are preferred, namely saturated fatty acids or monounsaturated fatty acids, with oleic acid being the most preferred. As a vegetable oil containing such fatty acids, for example, vegetable oils containing saturated fatty acids or monounsaturated fatty acids can be used, or vegetable oils that have undergone transesterification or other modifications can be used. Furthermore, to produce such vegetable oils containing fatty acids, plants can be improved through variety improvement, genetic engineering, gene editing, etc.

[0172] As a vegetable oil, for example, commercially available substances from companies such as Idemitsu Kosan Co., Ltd., Sankyo Oil & Chemical Co., Ltd., ENEOS Co., Ltd., Olisoy Co., Ltd., H&R Co., Ltd., Toyokuni Oil Co., Ltd., Fuji Kosan Co., Ltd., and Nissin Oliyo Group Co., Ltd. can be used.

[0173] Examples of animal fats include fish oil, tallow, or oleic alcohols derived from them.

[0174] When oil is present, from the viewpoint of the effectiveness of the present invention, its content relative to 100 parts by weight of the rubber component is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, even more preferably 15 parts by weight or more, and particularly preferably 20 parts by weight or more. Furthermore, this content is preferably 100 parts by weight or less, more preferably 80 parts by weight or less, and even more preferably 60 parts by weight or less.

[0175] (Liquid rubber) Liquid rubber is not specifically limited to any polymer that is liquid 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), and liquid farnesene rubber. These liquid rubbers can be used individually or in combination of two or more types.

[0176] The weight-average molecular weight (Mw) of the liquid rubber is typically less than 10,000, preferably less than 9,000, more preferably less than 6,000, and even more preferably less than 4,500. Furthermore, the Mw of the liquid rubber is preferably 100 or more, more preferably 500 or more, even more preferably 1,000 or more, even more preferably 1,500 or more, and particularly preferably 2,000 or more. When the Mw of the liquid rubber is within the above range, the effects of the present invention tend to be obtained better. Furthermore, in this specification, liquid rubber is not included in the above-described rubber components.

[0177] When liquid rubber is present, from the viewpoint of the effectiveness of the present invention, its content relative to 100 parts by mass of the rubber component is preferably 1 part by mass or more, more preferably 3 parts by mass or more, further preferably 5 parts by mass or more, even more preferably 7 parts by mass or more, and particularly preferably 10 parts by mass or more. Furthermore, this content is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, further preferably 30 parts by mass or less, and particularly preferably 25 parts by mass or less.

[0178] (Ester-based plasticizers) Examples of ester-based plasticizers include dibutyl adipate (DBA), diisobutyl adipate (DIBA), dioctyl adipate (DOA), di-2-ethylhexyl azelate (DOZ), dibutyl sebacate (DBS), diisononyl adipate (DINA), diethyl phthalate (DEP), dioctyl phthalate (DOP), dilauryl 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), and tricresyl phosphate (TXP). Ester-based plasticizers can be used alone or in combination of two or more.

[0179] From the viewpoint of wet grip performance, the content of plasticizer relative to 100 parts by weight of rubber component (the total amount when multiple plasticizers are used together) is preferably 20 parts by weight or more, more preferably 30 parts by weight or more, even more preferably 40 parts by weight or more, and particularly preferably 50 parts by weight or more. Furthermore, from the viewpoint of processability, it is preferably 150 parts by weight or less, more preferably 140 parts by weight or less, even more preferably 130 parts by weight or less, and particularly preferably 120 parts by weight or less.

[0180] Anti-aging agents As an antioxidant, there are no particular limitations; examples include naphthylamine-based antioxidants such as phenyl-α-naphthylamine; diphenylamine-based antioxidants such as octyl diphenylamine and 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine; 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), and N,N'-xylyl Antioxidants include p-phenylenediamine (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), and N,N'-di-2-naphthyl-p-phenylenediamine (DNPD); quinoline-based antioxidants such as polymers of 2,2,4-trimethyl-1,2-dihydroquinoline; monophenol-based antioxidants such as 2,6-di-tert-butyl-4-methylphenol and styrene-modified phenol; and bis, tri, and polyphenol-based antioxidants such as tetra[methylene-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionate]methane. Among these, p-phenylenediamine-based antioxidants and quinoline-based antioxidants are preferred, with polymers of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and 2,2,4-trimethyl-1,2-dihydroquinoline being more preferred. Commercially available products, for example, can be made by companies such as Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinsei Chemical Co., Ltd., and Flexis. Antioxidants can be used alone or in combination of two or more.

[0181] When antioxidants are present, their content relative to 100 parts by weight of the rubber component (the total amount when multiple antioxidants are used together) is preferably 1.0 parts by weight or more, more preferably 2.0 parts by weight or more, even more preferably 3.0 parts by weight or more, even more preferably 3.5 parts by weight or more, and particularly preferably 4.0 parts by weight or more. Furthermore, this content is preferably 10 parts by weight or less, more preferably 8.0 parts by weight or less, and even more preferably 6.0 parts by weight or less.

[0182] <Other Compounding Agents> In addition to rubber components and fillers, the rubber composition involved in this embodiment may also contain appropriate compounding agents commonly used in the tire industry, such as vulcanized rubber particles, processing aids, waxes, stearic acid, zinc oxide, vulcanizing agents, vulcanization accelerators, etc.

[0183] (vulcanized rubber granules) Vulcanized rubber granules are granules made of vulcanized rubber. Specifically, rubber powder as specified in JIS K 6316:2017 can be used. From the perspective of environmental concerns and cost, recycled rubber powder made from waste tire shreds is preferred. These vulcanized rubber granules can be made from one type alone or from two or more types in combination.

[0184] There are no particular limitations on the vulcanized rubber granules; they can be either unmodified or modified vulcanized rubber granules. Commercially available vulcanized rubber products, for example, can be products from companies such as Lehigh Corporation and Muraoka Rubber Industry Co., Ltd.

[0185] When vulcanized rubber particles are present, their content relative to 100 parts by mass of the rubber component can be appropriately adjusted, for example, within a range of greater than 1 part by mass and less than 80 parts by mass.

[0186] (Processing aids) Examples of processing aids include, for example, fatty acid metal salts, fatty acid amides, amide esters, silica surfactants, fatty acid esters, mixtures of fatty acid metal salts and amide esters, and mixtures of fatty acid metal salts and fatty acid amides. Commercially available substances from companies such as Schill+Seilacher and Performance-Additives can also be used as processing aids. These processing aids can be used individually or in combination of two or more.

[0187] When processing aids are included, from the viewpoint of improving processability, their content relative to 100 parts by weight of the rubber component is preferably greater than 0.5 parts by weight, more preferably greater than 1.0 parts by weight, and even more preferably greater than 1.5 parts by weight. Furthermore, from the viewpoint of abrasion resistance and tensile strength, it is preferably less than 10 parts by weight, more preferably less than 8.0 parts by weight, and even more preferably less than 5.0 parts by weight.

[0188] (wax) The wax used is not particularly limited, and any substance commonly used in the tire industry can be preferably used, such as mineral waxes and plant-derived waxes. Mineral waxes refer to waxes derived from mineral resources such as petroleum and natural gas. Plant-derived waxes refer to waxes derived from natural resources such as plants. Among these, mineral waxes are preferred. Examples of plant-derived waxes include rice bran wax, carnauba wax, and candelilla wax. Examples of mineral waxes include paraffin wax, microcrystalline wax, and selected special waxes of these, with paraffin wax being preferred. Furthermore, the wax involved in this embodiment is a stearic acid-free wax. For example, commercially available substances such as those from Ouchi Shinsei Chemical Co., Ltd., Nippon Seiwa Co., Ltd., and Paramelt Co., Ltd. can be used. These waxes can be used individually or in combination of two or more.

[0189] When wax is present, from the viewpoint of improving the weather resistance of rubber, its content relative to 100 parts by weight of rubber component is preferably greater than 0.5 parts by weight, more preferably greater than 1.0 parts by weight, and even more preferably greater than 1.5 parts by weight. Furthermore, from the viewpoint of preventing tire whitening caused by blooming, it is preferably less than 10 parts by weight, more preferably less than 7.0 parts by weight, and even more preferably less than 5.0 parts by weight.

[0190] (Stearic acid) When stearic acid is present, from a processability point of view, its content relative to 100 parts by weight of the rubber component is preferably greater than 0.5 parts by weight, more preferably greater than 1.0 parts by weight, and even more preferably greater than 1.5 parts by weight. Furthermore, from a vulcanization rate point of view, it is preferably less than 10 parts by weight, more preferably less than 8.0 parts by weight, and even more preferably less than 5.0 parts by weight.

[0191] (Zinc oxide) When zinc oxide is present, from a processability point of view, its content relative to 100 parts by weight of the rubber component is preferably greater than 0.5 parts by weight, more preferably greater than 1.0 parts by weight, and even more preferably greater than 1.5 parts by weight. Furthermore, from a wear resistance point of view, it is preferably less than 10 parts by weight, more preferably less than 8.0 parts by weight, and even more preferably less than 5.0 parts by weight.

[0192] (Vulcanizing agent) Sulfur is preferably used as a vulcanizing agent. Powdered sulfur, oil-treated sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, highly dispersible sulfur, etc., can be used as the sulfur.

[0193] When sulfur is used as a vulcanizing agent, from the viewpoint of ensuring a sufficient vulcanization reaction, its content relative to 100 parts by weight of the rubber component is preferably greater than 0.1 parts by weight, more preferably greater than 0.5 parts by weight, and even more preferably greater than 1.0 parts by weight. Furthermore, from the viewpoint of preventing deterioration, it is preferably less than 5.0 parts by weight, more preferably less than 3.0 parts by weight, and even more preferably less than 2.0 parts by weight. Moreover, when using oil-containing sulfur as a vulcanizing agent, the content of the vulcanizing agent is set as the total content of pure sulfur contained in the oil-containing sulfur.

[0194] Other than sulfur, known organic crosslinking agents can also be used as vulcanizing agents. There are no particular limitations on the organic crosslinking agent, as long as it is a substance capable of forming crosslinking chains other than polysulfide bonds. Examples include alkylphenol / sulfur chloride condensates, sodium 1,6-hexamethylene dithiosulfate dihydrate, 1,6-bis(N,N'-dibenzylthiocarbamoyl dithiohexane), and dicumyl peroxide. These organic crosslinking agents can be commercially available substances from companies such as Taoka Chemical Industry Co., Ltd., Lanxess Co., Ltd., and Flexis Co., Ltd.

[0195] (Vulcanization accelerator) There are no particular limitations on the type of vulcanization accelerator. Examples include sulfenamide-based vulcanization accelerators, thiazole-based vulcanization accelerators, guanidine-based vulcanization accelerators, thiuram-based vulcanization accelerators, thiourea-based vulcanization accelerators, dithiocarbamate-based vulcanization accelerators, aldehyde-amine-based vulcanization accelerators, aldehyde-amine-based vulcanization accelerators, imidazoline-based vulcanization accelerators, xanthate-based vulcanization accelerators, and caprolactam disulfides. These vulcanization accelerators can be used individually or in combination of two or more. However, from the perspective of achieving the desired effect, it is preferable to select one or more vulcanization accelerators from the categories of sulfenamide-based vulcanization accelerators, thiazole-based vulcanization accelerators, and guanidine-based vulcanization accelerators.

[0196] Examples of sulfenamide-based sulfidation accelerators include N-tert-butyl-2-benzothiazole sulfenamide (TBBS), N-cyclohexyl-2-benzothiazole sulfenamide (CBS), and N,N-dicyclohexyl-2-benzothiazole sulfenamide (DCBS).

[0197] Examples of thiazole-based sulfidation accelerators include 2-mercaptobenzothiazole (MBT) or its salts, di-2-benzothiazole disulfide (MBTS), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, and 2-(2,6-diethyl-4-morpholinothio)benzothiazole. Among these, MBTS and MBT are preferred, and MBTS is more preferred.

[0198] Examples of guanidine-based vulcanization accelerators include 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanidine, di-o-tolylguanidine salt of dicatecholborate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, and 1,3-di-o-isopropylphenyl-2-propionylguanidine.

[0199] When a vulcanization accelerator is included, from the viewpoint of ensuring a sufficient vulcanization rate, its content relative to 100 parts by mass of the rubber component (the total amount when multiple vulcanization accelerators are used together) is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass or more, even more preferably 2.0 parts by mass or more, even more preferably 3.0 parts by mass or more, and particularly preferably 4.0 parts by mass or more. Furthermore, from the viewpoint of suppressing blooming, the content of the vulcanization accelerator is preferably 10 parts by mass or less, more preferably 7.0 parts by mass or less.

[0200] In this specification, various materials containing carbon atoms (e.g., rubber, oil, resin, vulcanization accelerator, antioxidant, surfactant, etc.) can also be derived from carbon dioxide in the atmosphere. As a method for obtaining these various materials from carbon dioxide, carbon dioxide can be directly converted, or methane obtained through a methanation process that synthesizes methane from carbon dioxide can be converted.

[0201] [manufacture] The rubber composition described in this embodiment can be manufactured by known methods. For example, it can be manufactured by mixing the above-mentioned components using a rubber mixing apparatus such as an open rolling mill or a closed mixing mill (Banbury mixer, kneader, etc.).

[0202] The mixing process, for example, includes the following basic kneading process: mixing compounding agents and additives other than vulcanizing agents and vulcanization accelerators, and the final mixing process (F mixing): adding vulcanizing agents and vulcanization accelerators to the mixture obtained in the basic kneading process and mixing. Furthermore, the above-mentioned basic kneading process can also be broken down into multiple processes as needed. When breaking down the basic kneading process, the method can be: (1) pre-mixing a portion of the compounding agents and additives, masterbatching them, and then adding the remaining compounding agents and additives to the obtained masterbatch and mixing them, or (2) mixing all the compounding agents and additives mixed in the basic kneading process once, and then remilling the mixture more than once, etc. In the above method (1), the number of masterbatch is not limited, and it can be two or more. In addition, when the number of masterbatch is two or more, it can be in the manner that all the compounding agents and additives used in the basic kneading process are distributed in any masterbatch.

[0203] There are no particular limitations on the mixing conditions. For example, in the basic kneading process, mixing at a discharge temperature of 150–170°C for 3–10 minutes can be listed, and in the final kneading process, mixing at 70–110°C for 1–5 minutes can be listed. There are no particular limitations on the vulcanization conditions. For example, vulcanizing at 150–200°C for 10–30 minutes can be listed.

[0204] The tire according to this embodiment, having a tread composed of the above-described rubber composition, can be manufactured by conventional methods. That is, the tire can be manufactured by: mixing the above-described components as needed relative to the rubber composition; extruding the prepared uncured rubber composition according to the shape of the tread; bonding the resulting tread together with other tire components on a tire forming machine using conventional methods; forming an uncured tire by molding; and manufacturing the resulting uncured tire by heating and pressurizing it in a vulcanizing machine. There are no particular limitations on the vulcanization conditions; for example, vulcanizing at 150–200°C for 10–30 minutes can be cited.

[0205] [use] The tire of this embodiment can be used for any purpose, whether pneumatic or non-pneumatic, including passenger car tires, large passenger car tires, large SUV tires, racing tires, motorcycle tires, heavy-duty tires, and run-flat tires. Furthermore, passenger car tires refer to tires with a maximum load capacity of less than 1400 kg, intended for use in four-wheeled vehicles. Heavy-duty tires refer to tires with a maximum load capacity of 1400 kg or more. In addition to all-season tires and summer tires, the tires involved in this embodiment can also be used as winter tires, such as studless anti-skid tires.

Example

[0206] The following examples (embodiments) are considered preferred in practice, but the scope of the invention is not limited to these examples. Tires obtained according to Tables 1-1 to 2 were studied using the various reagents shown below, and the results calculated based on the evaluation methods described below are shown in Tables 1-1 to 2.

[0207] <Various Reagents> The reagents used in the examples and comparative examples are summarized below. IR-based rubber: TSR20(NR) SBR1: TUFDENE 2000R (S-SBR, styrene content: 25% by mass, vinyl content: 13% by mol%, Tg: -65℃, Mw: 450,000, non-oil-extended) manufactured by Asahi Kasei Corporation SBR2: F1810 (S-SBR, manufactured by LG Chem, styrene content: 18% by mass, vinyl content: 10% by mol%, Tg: -73℃, containing 5.0 parts by mass of oil-extended oil per 100 parts by mass of rubber solids) BR: UBEPOL BR (registered trademark) 150B manufactured by UBE Co., Ltd. (unmodified BR, cis content: 97 mol%, Mw: 440,000) Carbon Black 1: SHOBLACK N134 (N2SA: 148m) manufactured by Cabot Japan Co., Ltd. 2 / g, average primary particle size: 18nm) Carbon Black 2: SHOBLACK N220 (N2SA: 115m) manufactured by Cabot Japan Co., Ltd. 2 / g, average primary particle size: 22nm) Silica 1: ULTRASIL 9100GR (CTAB specific surface area: 200m²) manufactured by Evonik Industries. 2 / g, N2SA: 235m 2 / g) Silica 2: Solvay Zeosil Premium SW (CTAB specific surface area: 245m²) 2 / g, N2SA: 258m 2 / g) Silane coupling agent 1: Si266 (bis(3-triethoxysilylpropyl) disulfide) manufactured by Evonik Industries Silane coupling agent 2: NXT (3-octanoylthio-1-propyltriethoxysilane) manufactured by Evonik Industries. Resin component 1: SYLVATRAXX 4401 (a copolymer of α-methylstyrene and styrene, softening point: 85℃) manufactured by Kraton. Resin component 2: SYLVATARAXX 4150 (polyterpene resin, softening point: 115℃) manufactured by Kraton. Resin component 3: ExxonMobil's Oppera PR383 (hydrogenated DCPD / C9 resin, softening point: 103℃) Oil 1: VivaTec 500 (TDAE oil) manufactured by H&R Corporation. Oil 2: Sunflower seed oil produced by Nissin Oriyo Group Co., Ltd. (Oleic acid content in the fatty acids: 55% by mass, total content of polyunsaturated fatty acids in the fatty acids: 8% by mass) Liquid resin: Ricon 340 (liquid C5C9 series resin, Mw: 2400) manufactured by Clayville Company. Wax: OZOACE 0355 (paraffin wax) manufactured by Nippon Fine Wax Co., Ltd. Antioxidant 1: NOCRAC 6C (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine) manufactured by Ouchi Shinsei Chemical Co., Ltd. Anti-aging agent 2: NOCRAC RD (poly(2,2,4-trimethyl-1,2-dihydroquinoline)) manufactured by Ouchi Shinsei Chemical Co., Ltd. Processing aid: WB16 (a mixture of calcium soap and fatty acid amide) manufactured by STRUKTOL. Stearic acid: TSUBAKI stearic acid beads manufactured by Nippon Oil Co., Ltd. Zinc oxide: Zinc oxide No. 1 manufactured by Mitsui Metals & Minerals Co., Ltd. Sulfur: Powdered sulfur manufactured by Tsurumi Chemical Co., Ltd. Vulcanization accelerator 1: NOCCELLER CZ (N-cyclohexyl-2-benzothiazole sulfenamide (CBS)) manufactured by Ouchi Shinsei Chemical Co., Ltd. Vulcanization accelerator 2: NOCCELLER D (1,3-diphenylguanidine (DPG)) manufactured by Ouchi Shinsei Chemical Co., Ltd.

[0208] (Examples and Comparative Examples) According to the compounding formulations shown in Tables 1-1 and 2, using a 1.7L closed-type Banbury mixer, the sulfur and reagents other than the vulcanization accelerator were mixed for 1-10 minutes until the discharge temperature reached 150-160°C to obtain a compound. Then, vulcanizing agents and vulcanization accelerators were added to the obtained compound, and the mixture was kneaded for 4 minutes using a twin-screw open-roll mill until 105°C was reached to obtain an unvulcanized rubber composition. Using this unvulcanized rubber composition, the tires were extruded into the shape of a tread using an extruder with a die orifice of a specified shape, and bonded together with other tire components to produce unvulcanized tires. These tires were then vulcanized at 170°C to obtain the test tires (sizes of 205 / 65R15 in Tables 1-1 to 1-3, and 175 / 65R14 in Table 2). The tire weight G of the 205 / 65R15 tires in Tables 1-1 to 1-3 was 8.4 kg, and the tire weight G of the 175 / 65R14 tires in Table 2 was 6.5 kg. In addition, the maximum load capacity W of tires in Tables 1-1 to 1-3 L The weight of the tires in Table 1 is 660 kg, and the weight of the tires in Table 2 is 515 kg. Therefore, the G / W of the test tires in Tables 1-1 to 1-3 is... L The value is 0.0127, and the G / W of each test tire in Table 2 is... L It is 0.0126.

[0209] <Determination of Acetone Extraction (AE) Content> For rubber test pieces cut from the tread of each test tire, the AE (acetylene oxidative stress) was measured. The AE was determined by immersing each test piece in acetone for 72 hours, extracting the soluble components, measuring the mass of each test piece before and after extraction, and then calculating it using the following formula. Acetone extraction yield (%) = {(mass of vulcanized rubber test piece before extraction - mass of vulcanized rubber test piece after extraction) / (mass of rubber test piece before extraction)} × 100

[0210] Handling stability at high speeds Each test tire was installed on all wheels of the vehicle (domestic FF2000cc), and the vehicle was driven for 10 laps on a dry asphalt test track at approximately 120 km / h. During cornering, 20 test drivers provided sensory evaluations of the vehicle's swaying during entry, turning, and exiting corners. Evaluations were given on an integer scale of 1 to 5 points (higher scores for less swaying), and the total scores of the 20 test drivers were calculated. The total scores of the benchmark comparison examples (Comparison Example 1 in Tables 1-1 to 1-3, and Comparison Example 4 in Table 2) were converted to a baseline value (100), and the evaluation results of each test tire were expressed as an index proportional to the total score. A higher value indicates better handling stability at high speeds.

[0211] Table 1-1 Table 1-1 (Tire Size: 205 / 65R15)

[0212] Table 1-2 Table 1-22 (Tire Size: 205 / 65R15)

[0213] Table 1-3 Table 1-3 (Tire Size: 205 / 65R15)

[0214] Table 2 Table 2 (Tire Size: 175 / 65R14)

[0215] <Implementation Method> Examples of embodiments of the present invention are shown below. [1] A tire, characterized in that, It is a tire consisting of a carcass and a tread. The tread has one or more circumferential grooves. The tread is composed of a rubber composition containing rubber components, fillers, and resin components. The rubber composition contains isoprene-based rubber and styrene-butadiene rubber. The content of isoprene-based rubber in the rubber component is 40% by mass or more. The filler contains silicon dioxide. Relative to 100 parts by weight of the rubber component, the rubber composition contains at least 100 parts by weight of silica and at least 50 parts by weight of resin component. When the distance from the outermost radial direction of the tire carcass to the deepest part of the circumferential groove of the tread is defined as L (mm), the acetone extraction amount of the rubber composition is defined as AE (mass %), and the total filler content in the rubber composition relative to 100 parts by mass of the rubber component is defined as F (parts by mass), (F×AE) / L is greater than 170. [2] According to the tire described in [1] above, the rubber composition contains 130 or more, 200 or less, of silicon dioxide relative to 100 parts by mass of the rubber component, preferably 135 or more, 190 or less, and more preferably 140 or more, of silicon dioxide. [3] The tire according to [1] or [2] above, wherein the content of styrene-butadiene rubber in the rubber component is greater than 40% by mass, preferably 42% by mass or more and 60% by mass or less, more preferably 45% by mass or more and 58% by mass or less. [4] The tire according to any one of [1] to [3] above, wherein the CTAB specific surface area C of the silica is 190 m². 2 / g or more, preferably 200m 2 / g or more. [5] The tire according to any one of [1] to [4] above, wherein the styrene content of the styrene butadiene rubber is 20% by mass or more, preferably 22% by mass or more and 40% by mass or less. [6] The tire according to any one of [1] to [5] above, wherein the AE (mass%) is 25.0 or more. [7] The tire according to any one of [1] to [6] above, wherein the resin component contains at least one selected from C9 resin, dicyclopentadiene resin and terpene resin. [8] The tire according to any one of [1] to [7] above, wherein the rubber composition further contains a mercapto-based silane coupling agent. [9] The tire according to any one of [1] to [8] above, wherein the resin component contains liquid resin.

[10] The tire according to any one of [1] to [9] above, wherein the rubber composition contains liquid rubber.

[11] The tire according to any one of [1] to

[10] above, wherein the rubber composition contains vegetable oil.

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

[11] above, wherein, with respect to F and AE, F×AE is greater than 3500, preferably greater than 3600 and less than 8000.

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

[12] above, wherein, with respect to L and AE, L / AE is greater than 0.30, preferably greater than 0.33 and less than 0.50.

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

[13] above, wherein the CTAB specific surface area of ​​the silica is set as C(m²). 2 When C / L is greater than 20, preferably greater than 22, and more preferably greater than 25 and less than 35, the C / L ratio is greater than 20, preferably greater than 22, and more preferably greater than 25 and less than 35.

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

[14] above, wherein the maximum load capacity of the tire is set to W. L When the weight of the tire is set as G (kg), G / W L It is below 0.0170.< / c> < / l>

Claims

1. A tire, characterized in that, It is a tire consisting of a carcass and a tread. The tread has one or more circumferential grooves. The tread is composed of a rubber composition containing rubber components, fillers, and resin components. The rubber composition contains isoprene-based rubber and styrene-butadiene rubber. The content of isoprene-based rubber in the rubber component is 40% by mass or more. The filler contains silicon dioxide. Relative to 100 parts by weight of the rubber component, the rubber composition contains at least 100 parts by weight of silica and at least 50 parts by weight of resin component. Let L be the distance from the outermost radial direction of the tire carcass to the deepest part of the circumferential groove of the tread, let AE be the acetone extraction amount of the rubber composition, and let F be the total filler content in the rubber composition relative to 100 parts by mass of the rubber component. (F×AE) / L is greater than 170, The unit of L is mm, the unit of AE is mass%, and the unit of F is mass parts.

2. The tire according to claim 1, wherein, The rubber composition contains 130 or more parts by mass of silica relative to 100 parts by mass of the rubber component.

3. The tire according to claim 1 or 2, wherein, The styrene-butadiene rubber content in the rubber component is greater than 40% by mass.

4. The tire according to claim 1 or 2, wherein, The CTAB specific surface area C of the silica is 190 m². 2 / g or more.

5. The tire according to claim 1 or 2, wherein, The styrene-butadiene rubber has a styrene content of 20% by mass or more.

6. The tire according to claim 1 or 2, wherein, The AE is 25.0 or higher, and the unit of AE is mass%.

7. The tire according to claim 1 or 2, wherein, The resin component contains at least one selected from C9 series resins, dicyclopentadiene series resins, and terpene series resins.

8. The tire according to claim 1 or 2, wherein, The rubber composition further contains a mercapto-based silane coupling agent.

9. The tire according to claim 1 or 2, wherein, The resin component contains liquid resin.

10. The tire according to claim 1 or 2, wherein, The rubber composition contains liquid rubber.

11. The tire according to claim 1 or 2, wherein, The rubber composition contains vegetable oil.

12. The tire according to claim 1 or 2, wherein, Involving F and AE, F×AE is greater than 3500.

13. The tire according to claim 1 or 2, wherein, Involving L and AE, L / AE is greater than 0.

30.

14. The tire according to claim 1 or 2, wherein, When the CTAB specific surface area of ​​the silica is defined as C, C / L is greater than 20, and the unit of C is m². 2 / g.

15. The tire according to claim 1 or 2, wherein, Set the maximum load capacity of the tire to W. L When the weight of the tire is set as G, G / W L When W is below 0.0170, L Both G and G are in kg.

16. The tire according to claim 1 or 2, wherein the rubber composition contains 200 parts by mass or less of silica relative to 100 parts by mass of the rubber component.

17. The tire according to claim 1 or 2, wherein the rubber composition contains 100 parts by weight or less of a resin component relative to 100 parts by weight of the rubber component.

18. The tire according to claim 1 or 2, (F×AE) / L is less than 1000.

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