TIRES

Abstract

A tire is provided comprising a tread made of a rubber composition comprising a rubber component and fillers, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, wherein the isoprene-based rubber content in the rubber component is 40% by mass or more, wherein the glass transition temperature Tg of the styrene-butadiene rubber is -60°C or lower, wherein the fillers include silicon dioxide, wherein the silicon dioxide content is 130 parts by mass or more based on 100 parts by mass of the rubber component, and wherein T / F is less than 0.16, where T represents the thickness in mm of the tread and F represents the total content in parts by mass of the fillers based on 100 parts by mass of the rubber component in the rubber composition.

Description

TECHNICAL AREA

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

[0002] JP 2021-25006 A describes that for a tire comprising a tread made of a rubber composition comprising an isoprene-based rubber and silicon dioxide, and whose 20 °C tanδ and -20 °C tanδ are within a predetermined range, its fuel efficiency, abrasion resistance, steering stability during high-speed driving, and wet grip performance during high-speed driving are improved with good balance. SUMMARY OF THE INVENTION

[0003] In a case where an isoprene-based rubber and a styrene-butadiene rubber are used together, silicon dioxide tends to be predominantly present in the styrene-butadiene rubber layer, and it is less likely to disperse. Therefore, there is room for improvement in the performance of any tire.

[0004] On the other hand, in recent years, with the development of highways, it has also not been uncommon for drivers to travel at high speeds over long distances, and steering stability during high-speed driving is required for a pneumatic tire.

[0005] One object of the present invention is to provide a tire that improves steering stability during high-speed running.

[0006] The present invention relates to: a tire that includes a tread, the running surface is made up of a rubber composition comprising a rubber component and fillers, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, where the content of isoprene-based rubber in the rubber component is 40% by mass or more, where the glass transition temperature Tg of the styrene-butadiene rubber is -60 °C or lower, the fillers contain silicon dioxide, wherein the rubber composition comprises 130 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component, and where the T / F ratio is less than 0.16, where T represents a thickness in mm of the running surface and F represents a total filler content in parts by mass based on 100 parts by mass of the rubber component in the rubber composition.

[0007] According to the present invention, a tire is provided which improves steering stability during high-speed running. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is part of a cross-sectional view of a tire according to an embodiment of the present invention, passing through a tire axis of rotation. EXECUTIONAL FORMS FOR IMPLEMENTING THE INVENTION

[0008] A tire that is an embodiment of the present invention is described below. The tire according to the present embodiment is a tire comprising a tread, wherein the tread is composed of a rubber composition comprising a rubber component and fillers, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, wherein the isoprene-based rubber content in the rubber component is 40% by mass or more, wherein the glass transition temperature Tg of the styrene-butadiene rubber is -60°C or lower, wherein the fillers contain silicon dioxide, wherein the rubber composition comprises 130 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component, and wherein the T / F ratio is less than 0.16. where T represents a thickness in mm of the running surface and F represents a total filler content in parts by mass based on 100 parts by mass of the rubber component in the rubber composition.

[0009] Although it is not intended to be bound to any theory, the following may be considered as a reason why steering stability is improved during high-speed running in the present invention.

[0010] For example, in the tire according to the present invention, (1) if the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, and the isoprene-based rubber content in the rubber component is 40% by mass or more, a phase of the isoprene-based rubber of a certain size or more is formed in a rubber matrix, and an interface is created between this phase and a phase of the styrene-butadiene rubber, thereby enabling the mitigation of force transmission from a road surface during driving, which contributes to improved steering stability. Furthermore, (2) if the glass transition temperature Tg of the styrene-butadiene rubber is -60°C or lower, the temperature dependence of the modulus of elasticity in a high-temperature range is reduced, which contributes to improved steering stability during high-speed driving.(3) If the rubber composition includes 130 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component, it will be easy to obtain a polymer chain-strengthening effect by the silicon dioxide, which contributes to improved steering stability during high-speed operation. (4) If the ratio of total filler content to tread thickness is less than 0.16, such a ratio contributes to improved steering stability during high-speed operation. With the combined action of (1) to (4) described above, a significant improvement in steering stability during high-speed operation is expected.

[0011] The rubber composition preferably comprises 150 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component.

[0012] This is because it becomes easier to obtain an effect of strengthening a polymer chain through the silicon dioxide, and it is believed that steering stability during high-speed running is improved.

[0013] A CTAB-specific surface area C of the silicon dioxide is preferably 190 m². 2 / g or more.

[0014] If the CTAB-specific surface C 190 m 2 When the concentration is / g or higher, the number of bonding points between the silicon dioxide and a polymer increases, thus stabilizing the network structure. Therefore, it is assumed that steering stability during high-speed operation is further improved.

[0015] The rubber composition preferably comprises 50 parts by mass or more of a resin component based on 100 parts by mass of the rubber component.

[0016] When 50 or more parts of the resin component are combined, adhesive strength can be imparted to a rubber, and its ability to conform to a road surface is improved. Therefore, it is assumed that, in addition to the effects of the present invention, adhesion performance is enhanced.

[0017] The styrene content of the styrene-butadiene rubber is preferably 20 wt% or more.

[0018] The effect of mitigating the force input from a road surface while driving is further enhanced, so it is assumed that steering stability is further improved.

[0019] The amount of AE extractable by acetone, expressed as a mass % of the rubber composition, is preferably 25.0 or more.

[0020] The resin component preferably comprises at least one selected from the group consisting of a C9-based resin, a dicyclopentadiene-based resin and a terpene-based resin.

[0021] When the resin component described above is combined, adhesive strength can be imparted to the rubber, and its ability to follow a road surface is improved. Therefore, the force with which the rubber grips the road surface is enhanced, and it is assumed that, in addition to the effects of the present invention, adhesion performance is improved.

[0022] The rubber composition preferably comprises a mercapto-based silane coupling agent.

[0023] Since high reactivity is a property of the mercapto-based silane coupling agent, the number of bonding points between the polymer and the silicon dioxide is increased, and the reinforcing property is enhanced, thereby improving stiffness, and it is assumed that steering stability is further improved.

[0024] The resin component preferably comprises a liquid resin.

[0025] The rubber composition preferably comprises a liquid rubber.

[0026] The rubber composition preferably includes a vegetable oil.

[0027] If AE represents a mass-percentage of the rubber composition that can be extracted by acetone, then F × AE is preferably greater than 3500. If F × AE is within the range described above, the effect of polymer chain reinforcement by the fillers is enhanced, as is stiffness and heat generation due to friction between the fillers. Therefore, steering stability and wet grip performance are expected to be improved.

[0028] If AE represents a mass-percentage of the rubber composition that can be extracted by acetone, then T × AE is preferably greater than 400. If T × AE is within the range described above, the effect of polymer chain reinforcement by the fillers is enhanced, as is stiffness and heat generation due to friction between the fillers. Therefore, steering stability and wet grip performance are expected to be improved.

[0029] If C is a CTAB-specific surface area in m² 2 Since the T / C ratio is less than 0.10 per gram of silicon dioxide, it is preferable that the T / C ratio is less than 0.10. If the T / C ratio is within the range described above, the polymer chain strengthening effect of the silicon dioxide is enhanced, and the block stiffness is increased. Therefore, steering stability during high-speed operation is expected to be improved.

[0030] If W L G represents the maximum load capacity of the tire in kg and G represents the weight of the tire in kg, G / W L Preferably 0.0170 or smaller. <definitionen>

[0031] A "standardized condition" is a state in which the tire is mounted on a standardized rim, inflated to a standardized internal pressure, and under no load. Unless otherwise noted, a tire is used in a standardized condition.

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

[0033] A “standardized internal pressure” is an air pressure in a standard system containing a standard on which the tire is based, defined by the standard for each tire, and, for example, refers to a “MAXIMUM AIR PRESSURE” at JATMA, “INFLATION PRESSURE” at ETRTO, or to a maximum value described in the table “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES” at TRA, referenced in that order, as in the case of the standardized rim, and if there is an applicable size at the time of reference, the standardized internal pressure conforms to its standard.Furthermore, in the case of tires not defined by the standard, the standardized internal pressure shall refer to a standardized internal pressure (250 kPa or more) of another tire size (specified in the standard) for which the standardized rim is described as a standard rim, and if several standardized internal pressures of 250 kPa or more are described, it shall refer to the minimum value below that.

[0034] A "standardized load in kg" is a load within a standard system that includes a standard on which the tire is based, defined by the standard for each tire. For example, a "MAXIMUM LOAD CAPACITY" for JATMA, a "LOAD CAPACITY" for ETRTO, or a maximum value described in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" table for TRA. Reference is made to this load in that order, as in cases of a standardized rim and standardized inflation pressure. If an applicable size exists at the time of reference, the load conforms to its standard. Then, in the case of tires not defined by the standard, a maximum load capacity W is specified. L , which is obtained through a calculation and is defined as a standardized load.

[0035] A "maximum load capacity W" L The volume in kg is calculated using the following equation. "V" represents a virtual volume in mm³. 3 The dimensions of a tire are represented as follows: "Dt" represents the tire's outer diameter in mm in a standardized state, "Ht" represents the tire's cross-sectional height in mm in a radial direction in a cross-section along a plane containing a tire's axis of rotation, and "Wt" represents the tire's cross-sectional width in mm in the standardized state. If R represents the tire's rim diameter, Ht can be calculated using the following equation: (Dt - R) / 2. Wt is a value obtained by excluding any patterns, letters, or similar markings on the tire's sidewall. Additionally, the maximum load capacity has the same meaning as the standardized load described above. WL=0.000011×V+175 V=[(Dt / 2)2−(Dt / 2−Ht)2]×π×Wt

[0036] A “weight G in kg of a tire” refers to the weight of a single tire, excluding the weight of a rim. Conversely, if an element consisting of a sponge and sealant, a sensor element, or the like is provided within a tire lumen, the tire weight should be a weight that includes the weight of such an element.

[0037] A "tread" is an element that includes a part forming a ground contact area of ​​a tire, and is an element that, in relation to elements forming a tire skeleton with steel or textile material, such as a belt layer, a belt reinforcement layer, a carcass layer and the like, is arranged in a cross-section of the tire along a plane containing a tire axis of rotation on an outside in a tire radial direction, when the tire includes these elements.

[0038] A "tread thickness T in mm" is the thickness of the entire tread measured along a normal relative to a tread-ground contact area on a tire equator in a cross-section passing through a tire axis of rotation. In a case where it includes a circumferential groove on the tire equator, the thickness T is a thickness measured along a normal relative to the tread-ground contact area on the central section in a tire width direction of a rib section, which is one of rib sections present in the tire width direction on the two side faces of the circumferential groove, and whose central section lies close to the tire equator plane in the tire width direction.

[0039] A "groove" refers to a recessed portion within recesses formed on a tread section of a tire, having an opening width of 2.0 mm or more on the tread-ground contact patch. A recessed portion within recesses with an opening width of less than 2.0 mm on the tread-ground contact patch is referred to as a "sipe."

[0040] A "circumferential groove" refers to a groove that extends in one direction around the circumference of the tire. The circumferential groove can extend linearly along the circumference or it can extend in a wavy, sinusoidal, or zigzag pattern along the circumference.

[0041] A “rubber component of a rubber composition” refers to a component that contributes to crosslinking in the rubber composition and is generally a component with a weight mean molecular weight (Mw) of 10000 or more.

[0042] A "plasticizer" is a material that imparts plasticity to a rubber component and is a component extracted from a rubber compound using acetone. Examples of plasticizers include one that is liquid at 25°C and one that is solid at 25°C. However, the plasticizer should not contain wax or stearic acid, which are commonly used in the tire industry.

[0043] A “plasticizer content” also includes an amount of a plasticizer contained in a stretched rubber component that has previously been stretched with the plasticizer, such as oil, a resin component, liquid rubber, and the like. Furthermore, the same applies to an oil content, a resin component content, and a liquid rubber content; for example, in a case where the stretching component is oil, the stretching oil is included in the oil content.

[0044] A “glass transition temperature Tg of a rubber component” means a static glass transition temperature of each rubber component, calculated by a differential scanning calorimeter (for example, Q200, manufactured by TA Instruments Japan Inc.).

[0045] In the present description, a “glass transition temperature Tg in °C of a styrene-butadiene rubber” refers to a glass transition temperature calculated for each styrene-butadiene rubber and refers to Tg of each styrene-butadiene rubber even in a case where two or more styrene-butadiene rubbers are mixed in the rubber composition.

[0046] An “Acetone Extractable Amount (AE)” is a value calculated by the following equation after immersing each vulcanized rubber test piece in acetone for 72 hours in accordance with JIS K 6229 to extract a soluble component, and after measuring a mass of each test piece before and after extraction. (Amount extractable by acetone (mass %)) = {(Mass of rubber test piece before extraction - Mass of rubber test piece after extraction) / (Mass of rubber test piece before extraction)} × 100.

[0047] A “styrene content” is determined by pyrolysis gas chromatography or NMR measurement ( 1 H-NMR or 13 The styrene content is calculated using C-NMR. For a component quantity, such as a "styrene content," there is a true value which, unlike physical property values ​​such as a complex modulus of elasticity (E*) and the like, does not depend on any measurement method. Therefore, it is preferable to use a measurement method that is as accurate as possible. Furthermore, in this description, "pyrolysis gas chromatography" refers to a process of heating a sample by means of a pyrolysis device, separating individual components contained in a gas-phase component generated by this heating from one another using a separation column, and analyzing each isolated component. The styrene content, for example, is applied to a rubber component with a repeating unit (styrene unit) derived from styrene, such as an SBR and the like.

[0048] A "styrene content in mass percent of a styrene-butadiene rubber" is the styrene content in mass percent of a styrene-butadiene rubber (SBR). In a case where a rubber component comprises only one type of SBR, it is the styrene content of that SBR. In a case where the rubber component comprises several types of SBR, it is calculated by summing products obtained by multiplying the styrene content of each SBR by a composite mass percent of that SBR, where the total content of all SBRs is set to 100 mass percent.

[0049] For example, if a rubber component consists of 20 wt% of a first SBR (styrene content: 25 wt%), 30 wt% of a second SBR (styrene content: 27.5 wt%) and 50 wt% of a BR, the styrene content of the styrene-butadiene rubber is 26.5 wt% (= (25 × 40 / 100) + (27.5 × 60 / 100)).

[0050] A “vinyl content (unit amount of 1,2-bound butadiene)” is determined by pyrolysis gas chromatography or NMR measurement ( 1 H-NMR or 13 The vinyl content (C-NMR) is calculated. There is also a true value for "vinyl content" which, like "styrene content", does not depend on any specific measurement method. Therefore, it is preferable to use a measurement method that is as accurate as possible.

[0051] A “cis content (cis-1,4-bound butadiene unit amount)” is a value determined by infrared absorption spectrometry in accordance with JIS K 6239-2:2017 or NMR measurement ( 1 H-NMR or 13 The term "cis content" is measured using C-NMR and is applied, for example, to a rubber component with a repeating unit derived from butadiene, such as a BR and the like. There is also a true value for a "cis content" that does not depend on any specific measurement method, unlike a "styrene content." Therefore, it is preferable to use a measurement method that is as accurate as possible.

[0052] A "weight-mean molecular weight (Mw)" can be calculated for a standard polystyrene based on measurements obtained by gel permeation chromatography (GPC) (for example, the GPC-8000 series manufactured by Tosoh Corporation, detector: differential refractometer, column: TSKgel (registered trademark) SuperMultiporeHZ-M manufactured by Tosoh Corporation). It is applied, for example, to an SBR, a BR, a plasticizing agent, and the like.

[0053] A “specific nitrogen adsorption surface (N2SA) of soot” is measured according to JIS K 6217-2:2017.

[0054] A “specific nitrogen adsorption surface (N2SA) of silicon dioxide” is measured by a BET method according to ASTM D3037-93.

[0055] A “CTAB (cetyltrimethylammonium bromide)-specific surface area C of silicon dioxide” is measured according to ASTM D 3765-92. In a case where a rubber composition includes only one type of silicon dioxide, the “CTAB-specific surface area C of silicon dioxide” is a CTAB-specific surface area of ​​that silicon dioxide. In a case where the rubber composition includes several types of silicon dioxide, it is calculated by summing products obtained by multiplying a CTAB-specific surface area of ​​each silicon dioxide by a composite mass-percentage of that silicon dioxide, where the total content of all types of silicon dioxide is set to 100 mass-percentage.

[0056] An "average primary particle size" is a value calculated by arithmetic meaning the particle sizes of 400 particles photographed with a transmission or scanning electron microscope. In cases where the particle is spherical, the diameter of the sphere is defined as the particle size; for shapes other than spherical, an equivalent circle diameter (positive square root of "4 × (area of ​​particle) / n") calculated from a microscope image is defined as the particle size. The average primary particle size is applied to silicon dioxide, carbon black, and similar materials.

[0057] A “softening point of a resin component” is a temperature at which a sphere falls when the softening point specified in JIS K 6220-1:2015 7.7 is measured using a ring-and-ball softening point gauge.

[0058] One embodiment is described in more detail below. However, the following descriptions are for illustrative purposes only, and the present invention is not limited to the content of these descriptions. Furthermore, although the embodiment is described by appropriate use of the drawings, the drawings are merely illustrative.

[0059] The tire according to the present embodiment is a tire comprising a tread, wherein the tread is composed of a predetermined rubber composition, wherein the ratio T / F is less than 0.16, where T represents a thickness in mm of the tread and F represents a total filler content in parts by mass based on 100 parts by mass of a rubber component in the rubber composition forming the tread. [Tires]

[0060] The tread according to the present embodiment comprises at least one rubber layer. Although a configuration of the tread is not particularly restricted, the tread may comprise two or more rubber layers and may, for example, have a configuration in which the tread consists of a first layer and a second layer, an outer surface of the first layer forming a tread surface, and the second layer being adjacent to the inside of the first layer in a tire radial direction. The rubber layers forming the tread may be formed by three or more layers, such as a configuration in which the tread includes a third layer on the inside of the second layer in the tire radial direction.In a case where the running surface comprises two or more rubber layers, it is sufficient that a rubber composition forming any one of the rubber layers is the rubber composition according to the present embodiment, and the first layer is preferably the rubber composition according to the present embodiment, and all two or more rubber layers are further preferably the rubber composition according to the present embodiment.

[0061] Fig. Figure 1 is a cross-sectional view, schematically showing part of the tire. Fig. 1 is a vertical direction, a tire radial direction; a horizontal direction is a tire width direction; and a direction perpendicular to a paper surface is a tire circumferential direction.

[0062] The tread of Fig. 1 comprises a first layer 6, whose outer surface forms a running surface 1, and a second layer 7, which is radially adjacent to an inner side of the first layer 6. The running surface of Fig. 1 comprises several circumferential grooves 2 that extend continuously in a tire circumferential direction.

[0063] T-thickness is the thickness of the entire tread surface measured along a normal to a tread-ground contact area on a tire equator in a cross-section passing through a tire axis of rotation.

[0064] In the present embodiment, the thickness T of the running surface is preferably 8.0 mm or more, more preferably 8.5 mm or more, and even more preferably 9.0 mm or more. Furthermore, the thickness T of the running surface is preferably 22.0 mm or less, more preferably 21.0 mm or less, and even more preferably 20.0 mm or less.

[0065] In the present embodiment, where T represents the thickness in mm of the tread and F represents the total filler content in parts by mass based on 100 parts by mass of the rubber component in the rubber composition forming the tread, the T / F ratio is less than 0.16. From the perspective of the effects of the present invention, the T / F ratio is preferably less than 0.15, more preferably less than 0.14, still more preferably less than 0.13, and particularly preferably less than 0.12. Furthermore, in the present embodiment, the T / F ratio is preferably greater than 0.04, more preferably greater than 0.05, and still more preferably greater than 0.06. The total filler content F in parts by mass based on 100 parts by mass of the rubber component in the rubber composition is described below.

[0066] A maximum load capacity W L The weight in kg of the tire according to the present embodiment, from the perspective of exerting the effects of the present invention, is preferably 300 or more, more preferably 400 or more, still more preferably 450 or more, still more preferably 500 or more, still more preferably 550 or more, and particularly preferably 600 or more. Furthermore, the maximum load capacity W L In kg, for example, from the perspective of exerting the effects of the present invention, the weight may be 1300 or less, 1200 or less, 1100 or less, 1000 or less, 900 or less, 800 or less, or 700 or less. Furthermore, the maximum load capacity W can be L The volume can be increased by increasing a virtual volume V of the space occupied by the tire, and can also be decreased in the opposite way.

[0067] The weight G in kg of the tire according to the present embodiment is preferably 6.0 or more, more preferably 6.5 or more, even more preferably 7.0 or more, and particularly preferably 7.5 or more. On the other hand, an upper limit for the tire weight G in kg is normally 100 or less and may, for example, be 80 or less, 60 or less, 40 or less, 20 or less, 15 or less, or the like, but is not particularly restricted. Furthermore, the tire weight G can be changed by a conventional method, that is, it can be increased by increasing a specific weight of the tire or a thickness of each element of the tire, and can also be decreased in the opposite way.

[0068] A ratio (G / W L ) of the tire weight G in kg to the maximum load capacity W L In kg, from the perspective of the effects of the present invention, preferably 0.0170 or less, more preferably 0.0160 or less, and even more preferably 0.0150 or less. On the other hand, a lower limit of the G / W is L from the point of view of the effects of the present invention, it is not particularly limited and can be, for example, 0.0110 or more, 0.0115 or more, 0.0120 or 0.0125 or more. <Durch Aceton extrahierbare Menge AE>

[0069] For the purpose of improving the dispersibility of silicon dioxide, the amount of acetone extractable by mass (AE) in the rubber composition forming the running surface is preferably 16.0 or more, more preferably 18.0 or more, still more preferably 20.0 or more, still more preferably 22.0 or more, and particularly preferably 25.0 or more. Furthermore, the amount of acetone extractable by mass (AE) is preferably 35.0 or less, more preferably 33.0 or less, and still more preferably 31.0 or less. The amount of acetone extractable from the rubber composition can be increased by increasing the amount of a soluble component and can be decreased by decreasing the amount of the soluble component. Examples of soluble components incorporated into the rubber composition include, for example, a plasticizer, a liquid rubber, and the like. <F × AE>

[0070] In the rubber composition forming the tread, where F represents a total filler content in parts by mass based on 100 parts by mass of the rubber component in the rubber composition, F × AE, from the perspective of the effects of the present invention, is preferably greater than 2300, more preferably greater than 2500, still more preferably greater than 2800, still more preferably greater than 3000, still more preferably greater than 3200, still more preferably greater than 3500, and particularly preferably greater than 3600. On the other hand, an upper limit of F × AE is preferably less than 8000, more preferably less than 7500, and still more preferably less than 7000, but is not particularly restricted. <T × AE>

[0071] From the perspective of the effects of the present invention, T × AE is preferably greater than 350, more preferably greater than 370, even more preferably greater than 400, and particularly preferably greater than 420. On the other hand, an upper limit of T × AE is preferably less than 520 and more preferably less than 500, but is not particularly restricted. <t c>

[0072] If C is a CTAB-specific surface area in m² 2 The T / C ratio, representing the silicon dioxide in the predetermined rubber composition, is preferably less than 0.11, more preferably less than 0.10, and even more preferably less than 0.09, from the perspective of the effects of the present invention. On the other hand, a lower limit for T / C is preferably more than 0.02, more preferably more than 0.03, and even more preferably more than 0.04, but is not particularly restricted. The CTAB-specific surface area C in m² 2 The amount of silicon dioxide per gram is described below. [Rubber composition]

[0073] Any rubber composition forming the tread according to the present embodiment comprises a rubber component and fillers, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, wherein the isoprene-based rubber content in the rubber component is 40% by weight or more, wherein the glass transition temperature Tg of the styrene-butadiene rubber is -60°C or lower, wherein the fillers contain silicon dioxide and comprise 130 parts by weight or more of silicon dioxide based on 100 parts by weight of the rubber component, and it can be produced using the raw materials described below. The rubber composition forming the tread according to the present embodiment (hereinafter referred to as a rubber composition according to the present embodiment) is described below. <kautschukkomponente>

[0074] The rubber composition according to the present embodiment preferably comprises a diene-based rubber as one of the rubber components. Any rubber components commonly used in the tire industry can be suitable as the diene-based rubber. In particular, examples of the diene-based rubber include isoprene-based rubber, butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), styrene-isoprene butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and the like. These diene-based rubbers can be used alone, or two or more of them can be used in combination.The content of a diene-based rubber in the rubber component according to the present embodiment is preferably 85% by weight or more, more preferably 90% by weight or more, even more preferably 95% by weight or more, and particularly preferably 98% by weight or more. Furthermore, it can be a rubber component consisting of a diene-based rubber.

[0075] The rubber component according to the present embodiment comprises an isoprene-based rubber and an SBR, and preferably comprises an isoprene-based rubber, an SBR and a BR. (Isoprene-based rubber)

[0076] Isoprene-based rubbers commonly used in the tire industry, such as isoprene rubber (IR), natural rubber, and similar types, can be used. Examples of natural rubber include not only unmodified natural rubber (NR) but also modified natural rubbers, such as epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), deproteinized natural rubber (DPNR), ultrapure natural rubber, grafted natural rubber, and the like. These isoprene-based rubbers can be used individually, or two or more can be used in combination.

[0077] The NR is not particularly restricted, and those commonly used in the tire industry can be used; examples include SIR20, RSS#3, TSR20, and the like.

[0078] According to the present embodiment, the content of an isoprene-based rubber in the rubber component is, from the perspective of the effects of the present invention, 40% by mass or more, preferably 45% by mass or more, and more preferably 50% by mass or more. Furthermore, from the perspective of the effects of the present invention, the content is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less. (SBR)

[0079] The SBR is not particularly restricted, and an unmodified solution-polymerized SBR (S-SBR), an unmodified emulsion-polymerized SBR (E-SBR), and the like may be used. Among these, S-SBR is preferred. Furthermore, modified SBRs (a modified S-SBR, a modified E-SBR), and the like, may also be used. Examples of modified SBR include an SBR modified at its end and / or main chain using a compound having a functional group as described below (a modifier); a modified SBR coupled to tin, a silicon compound, etc. (a modified SBR of condensate or with a branched structure, etc.); and the like. Hydrogenated versions of these SBRs (hydrogenated SBRs), and the like, may also be used. These SBRs may be used individually, or two or more of them may be used in combination.

[0080] The functional group of the modifier is preferably a functional group containing at least one element selected from the group consisting of silicon, nitrogen and oxygen. Examples of such a functional group include, for example, an amino group, an amide group, a silyl group, an alkoxysilyl group, an isocyanate group, an imino group, an imidazole group, a urea group, an ether group, a carbonyl group, an oxycarbonyl group, a mercapto group, a sulfide group, a disulfide group, a sulfonyl group, a sulfinyl group, a thiocarbonyl group, an ammonium group, an imide group, a hydrazo group, an azo group, a diazo group, a carboxyl group, a nitrile group, a pyridyl group, an alkoxy group (preferably an alkoxy group with 1 to 6 carbon atoms), a hydroxyl group, an oxy group, an epoxy group and the like, and an amino group and / or an alkoxysilyl group are preferred.The amino group is preferably an amino group substituted with one or two alkyl groups having 1 to 6 carbon atoms. Specific examples of alkoxysilyl include, for example, trimethoxysilyl, triethoxysilyl, triisopropoxysilyl, dimethoxymethylsilyl, diethoxymethylsilyl, dimethylmethoxysilyl, dimethylethoxysilyl, and the like.

[0081] An oil-enriched or non-oil-enriched SBR can be used as an SBR. The SBRs that can be used in the present embodiment include those commercially available from JSR Corporation, Sumitomo Chemical Co., Ltd., Ube Corporation, Asahi Kasei Corporation, ZS Elastomer Co., Ltd., ARLANXEO, etc.

[0082] In the present embodiment, from the perspective of the effects of the present invention, the glass transition temperature Tg of an SBR is -60 °C or lower, preferably -62 °C or lower, more preferably -65 °C or lower, even more preferably -68 °C or lower, and most preferably -70 °C or lower. Furthermore, the glass transition temperature Tg of the SBR refers to a glass transition temperature of each SBR measured by the method described above for a “glass transition temperature Tg of a rubber component”.

[0083] The styrene content of an SBR is preferably 10 wt% or more, more preferably 15 wt% or more, even more preferably 20 wt% or more, and even more preferably 22 wt% or more. Furthermore, the styrene content of the SBR is preferably 45 wt% or less, more preferably 40 wt% or less, and even more preferably 35 wt% or less. The styrene content of the SBR is also measured using the measurement method described above.

[0084] To ensure hysteresis loss, the vinyl content of an SBR is preferably more than 5 mol%, more preferably more than 10 mol%, and even more preferably more than 15 mol%. Furthermore, to improve fuel efficiency, the vinyl content of the SBR is preferably less than 60 mol%, more preferably less than 50 mol%, and even more preferably less than 40 mol%. The vinyl content of the SBR is also measured using the measurement method described above.

[0085] From the perspective of the effects of the present invention, the weight-average molecular weight (Mw) of an SBR is preferably more than 80,000, more preferably more than 100,000, even more preferably more than 150,000, and particularly preferably more than 500,000. Furthermore, considering crosslink uniformity, etc., the Mw is preferably less than 2,000,000, more preferably less than 1,500,000, and even more preferably less than 1,100,000. The Mw of the SBR is also measured using the measurement method described above.

[0086] For the purposes of the effects of the present invention, the SBR content in the rubber component is preferably 15 wt% or more, more preferably 20 wt% or more, more preferably 30 wt% or more, more preferably 40 wt% or more, more preferably more than 40 wt%, more preferably 42 wt% or more, more preferably 44 wt% or more, and particularly preferably 45 wt% or more. Furthermore, the SBR content in the rubber component is preferably 60 wt% or less, more preferably 58 wt% or less, more preferably 55 wt% or less, more preferably 53 wt% or less, and particularly preferably 50 wt% or less. (BR)

[0087] A rubber (BR) is not particularly restricted, and those commonly used in the tire industry can be employed, such as a BR with a cis content of less than 50 mol% (a cis-poor BR), a BR with a cis content of 90 mol% or more (a cis-rich BR), a rare-earth-based butadiene rubber synthesized using a rare-earth-based catalyst (a rare-earth-based BR), a BR containing a syndiotactic polybutadiene crystal (an SPB-containing BR), a modified BR (a cis-rich modified BR, a cis-poor modified BR), and the like. These BRs can be used individually, or two or more of them can be used in combination.

[0088] For example, cis-rich rubbers (BRs) from Zeon Corporation, UBE Corporation, JSR Corporation, etc., can be used. Including a cis-rich BR in the rubber composition can improve low-temperature properties and abrasion resistance. The cis content of a cis-rich 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 a BR is measured using the measurement method described above.

[0089] The rare-earth-based BR is synthesized using a rare-earth-element-based catalyst and has a vinyl content preferably less than 1.8 mol%, more preferably less than 1.6 mol%, and still more preferably less than 1.5 mol%, and a cis content preferably more than 95 mol%, more preferably more than 96 mol%, and still more preferably more than 97 mol%. For example, the rare-earth-based BR can be one of those commercially available from LANXESS, etc.

[0090] Examples of SPB-containing BR include those in which 1,2-syndiotactic polybutadiene crystal is chemically bonded and dispersed with BR, but not those in which the crystal is simply dispersed in the BR. BRs commercially available from UBE Corporation, etc., can be considered as such SPB-containing BRs.

[0091] Examples of modified BR include BRs modified with the same functional groups as described above for SBR, and the like, and a modified butadiene rubber (modified BR) modified at its end and / or main chain with a functional group comprising at least one element selected from the group consisting of silicon, nitrogen and oxygen may also be used appropriately.

[0092] Examples of other modified BRs include those obtained by adding a tin compound after polymerizing 1,3-butadiene with a lithium initiator, with the end of the modified BR molecule further bonded by a tin-carbon bond (tin-modified BRs), and the like. Furthermore, the modified BR can be either non-hydrogenated or hydrogenated.

[0093] The weight-average molecular weight (Mw) of a BR is preferably greater than 300,000, more preferably greater than 350,000, and even more preferably greater than 400,000, from the perspective of abrasion resistance. Furthermore, from the perspective of crosslinking uniformity, etc., the Mw is preferably less than 2,000,000, more preferably less than 1,000,000, and even more preferably less than 500,000. In addition, the Mw can be calculated using the measurement method described above.

[0094] The content of BR in the rubber component is preferably 1 wt% or more, more preferably 3 wt% or more, even more preferably 5 wt% or more, even more preferably 7 wt% or more, and particularly preferably 10 wt% or more, but is not particularly restricted. Furthermore, the content of BR in the rubber component is preferably less than 40 wt%, more preferably less than 30 wt%, even more preferably less than 20 wt%, even more preferably 18 wt% or less, and particularly preferably 16 wt% or less. (Other rubber components)

[0095] The rubber component may comprise a rubber component other than diene-based rubbers, as long as it does not affect the effects of the present invention. A crosslinkable rubber component commonly used in the tire industry may be used as a rubber component other than diene-based rubbers. Examples include non-diene-based rubbers such as butyl rubber (IIR), halogenated butyl rubber, ethylene propylene rubber, polynorbornene rubber, silicone rubber, polyethylene chloride rubber, fluororubber (FKM), acrylic rubber (ACM), hydrin rubber, and the like. Furthermore, in addition to the rubber components described above, it may or may not include a known thermoplastic elastomer.The other rubber components can be used alone, or two or more of them can be used in combination. (Rubber component synthesized from recycled / biomass-derived raw material)

[0096] A monomer that is a structural unit of a synthetic rubber, such as IR, SBR, BR, and the like, can be one derived from earth resources, such as petroleum, natural gas, and the like, or one recycled from a rubber product, such as a tire, and the like, or from a non-rubber product, such as polystyrene, and the like. Examples of monomers obtained through recycling (recycled monomers) include, but are not limited to, recycled polyisoprene, recycled butadiene, recycled aromatic vinyl compounds, and the like. Examples of butadiene, as described above, include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds include, but are not limited to, styrene and the like.These include recycled polyisoprene (recycled isoprene), recycled butadiene (recycled butadiene), and / or recycled styrene (recycled styrene), preferably used as raw materials.

[0097] A process for producing a recycled monomer is not particularly restricted; examples include, for instance, the synthesis of a recycled monomer from recycled naphtha obtained by decomposing a rubber product, such as a tire. Furthermore, a process for producing recycled naphtha is not particularly restricted, and recycled naphtha can be obtained, for example, by decomposing a rubber product, such as a tire, under high temperature and high pressure, by decomposing it using microwaves, or by mechanical pulverization followed by extraction.

[0098] Furthermore, a monomer that is a structural unit of a polymer, such as an IR, an SBR, a BR, and the like, can be one derived from biomass. In this description, "biomass" refers to a material derived from natural resources, such as plants and the like. Examples of biomass include, but are not limited to, agricultural, forestry, and fishery products, sugar, wood waste, plant residues after the capture of a useful component, plant-derived ethanol, biomass naphtha, and the like.

[0099] Examples of biomass-derived monomers (biomass monomers) include, but are not specifically limited to, biomass-derived butadiene, biomass-derived aromatic vinyl compounds, and the like. Examples of butadiene, as described above, include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds, as described above, include, but are not specifically limited to, styrene and the like. Furthermore, a process for producing a biomass monomer is not specifically limited; examples include, for instance, a process by biological and / or chemical and / or physical conversion of an animal or plant, and the like.Microbial fermentation is representative of biological conversion, and examples of chemical and / or physical conversion include a process that uses a catalyst, a process that uses high heat, a process that uses high pressure, a process that uses an electromagnetic wave, a process that uses a critical fluid, combinations thereof, and the like.

[0100] Examples of a polymer synthesized from a biomass monomer component (biomass polymer) include, but are not specifically limited to, a polybutadiene rubber synthesized from biomass-derived butadiene, an aromatic vinyl / butadiene copolymer synthesized from biomass-derived butadiene and / or a biomass-derived aromatic vinyl compound, and the like. Examples of aromatic vinyl / butadiene copolymers include, for example, a styrene-butadiene rubber synthesized from biomass-derived butadiene and / or biomass-derived styrene, and the like.

[0101] Whether a polymer raw material is derived from biomass or not can be determined by pMC (percent modern carbon), measured according to ASTM D6866-10. Here, "pMC" means a ratio of 14 C concentration of a sample to 14 The carbon concentration of a modern standard carbon (modern standard reference) is a value used as an index indicating the biomass ratio of a compound. The meaning of this value is mentioned below.

[0102] In 1 mol of carbon atoms (6.02 × 10 23 There are approximately 6.02 × 10 11 14 C, which are about one trillionth the number of normal carbon atoms. A half-life of 14 C is 5730 years, and 14 Carbon dioxide decreases regularly. Therefore, in the case of fossil fuels, such as coal, oil, natural gas, and the like, where it is assumed that 226,000 years or more have passed since carbon dioxide was absorbed by plants in the atmosphere to be fixed, all 14 Carbon elements, which were present at the beginning of the fixation, decay. Therefore, fossil fuels, such as coal, oil, natural gas, and the like, contain no carbon in the current 21st century. 14 Carbon element. Accordingly, chemical substances produced using these fossil fuels as raw materials also contain no carbon element. 14 C-element.

[0103] On the other hand 14 C is constantly produced by cosmic rays that cause nuclear reactions in the atmosphere. Therefore, a decrease of 14 C due to radioactive decay and the production of 14 C is balanced due to nuclear reactions and the amount of 14 The temperature of carbon (C) has been constant in the Earth's atmospheric environment. Therefore, the 14 Carbon concentration of substances derived from biomass resources that have circulated in the current environment, to a value of approximately 1 × 10 -12 Molar percentages are based on the total carbon atoms, as described above. Accordingly, by using the difference between these values, a biomass ratio in a given compound can be calculated.

[0104] This 14 C is generally measured as follows. Using accelerator mass spectrometry based on a tandem accelerator, a 13 C concentration ( 13 C / 12 C) and a 14 C concentration ( 14 C / 12 C) measured. During the measurements, a 14 The carbon concentration in a circulating carbon in nature from 1950 is used as the modern standard reference, which serves as a reference for the 14 The carbon concentration is determined. An oxalic acid standard provided by the National Institute of Standards and Technology (NIST) is used as a specific reference material. The specific radioactivity of carbon in this oxalic acid (radioactivity intensity of 14 C per gram of carbon) is sorted for each carbon isotope. 13 C is corrected to a constant value, and a value corrected for attenuation correction from 1950 to the measurement date is used as a standard. 14 A carbon concentration value (100%) is used. A ratio of this value to an actual measured value for a sample is called a pMC value.

[0105] Thus, when a rubber is produced from a material derived from 100% biomass, the 14 The carbon concentration has a value of approximately 110 pMC, as it is often not equal to 100 under normal conditions, although there are regional differences and the like. On the other hand, it shows when this 14 When the carbon concentration of a chemical substance derived from a fossil fuel, such as petroleum, is measured, it will be approximately 0 pMC (for example, 0.3 pMC). This value corresponds to a biomass ratio of 0%, as mentioned above.

[0106] Based on the above, it is suitable in terms of environmental protection to use a material such as a rubber with a high pMC value, and the like, that is, a material such as a rubber with a high biomass ratio, and the like, for a rubber composition. <Füllstoff>

[0107] The rubber composition according to the present embodiment comprises 130 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component as a filler. Furthermore, the fillers preferably contain silicon dioxide and carbon black, or the fillers may be fillers consisting of carbon black and silicon dioxide. (Silicon dioxide)

[0108] Silicon dioxide is not particularly restricted, and those commonly used in the tire industry can be employed, such as silicon dioxide produced by a dry process (anhydrous silicon dioxide), silicon dioxide produced by a wet process (hydrous silicon dioxide), and the like. The source of silicon dioxide is also not particularly restricted and can be, for example, a raw material derived from a mineral, such as quartz, or a raw material derived from a biological substance, such as rice husks (for example, silicon dioxide from a biomass material, such as rice husks, and the like), or silicon dioxide recycled from a silicon dioxide-containing product. Among these, hydrous silicon dioxide produced by a wet process is preferred because it contains many silanol groups.Silicon dioxide can be used alone, or two or more of them can be used in combination.

[0109] Silicon dioxide from a biomass material can be obtained, for example, by burning rice husks to obtain rice husk ash, extracting silicate from the rice husk ash using a sodium hydroxide solution, producing silicon dioxide by reacting the silicate with sulfuric acid in the same way as for conventional wet silicon dioxide, and filtering, washing with water, drying, and pulverizing the silicon dioxide precipitates.

[0110] Silicon dioxide recycled from a product containing silicon dioxide can be silicon dioxide recovered from such a product as an electronic component, such as a semiconductor, a tire, a desiccant, a filter material like diatomaceous earth, or the like. Furthermore, the recovery method is not particularly restricted; examples include pyrolysis, decomposition by electromagnetic waves, and the like. Silicon dioxide recovered from an electronic component, such as a semiconductor or the like, or from a tire, is preferred.

[0111] When silicon dioxide crystallizes, it is insoluble in water, and silicic acid, a component of it, cannot be used. Crystallization of silicon dioxide in rice hull ash can be suppressed by controlling the firing temperature and duration (see JP 2009-2594 A, Akita Prefectural University Web Journal B / 2019, Vol. 6, pp. 216-222, etc.). Amorphous silicon dioxide extracted from rice hulls can be obtained from sources such as Wilmar, etc.

[0112] A CTAB-specific surface area C of silicon dioxide is preferably 110 m² from the point of view of the effects of the present invention. 2 / g or more, preferably 140 m 2 / g or more, preferably 170 m 2 / g or more, preferably 190 m 2 / g or more and especially preferably 200 m 2 / g or more. Furthermore, the CTAB-specific surface area C is preferably 300 m². 2 / g or less, preferably 280 m 2 / g or less and even more preferably 260 m 2 / g or less. Furthermore, the CTAB of silicon dioxide is measured using the measurement method described above.

[0113] From the perspective of the effects of the present invention, a specific nitrogen adsorption surface area (N2SA) of silicon dioxide is preferably more than 110 m². 2 / g, preferably more than 130 m 2 / g, even more preferably more than 150 m 2 / g, even more preferably more than 170 m 2 / g, even more preferably more than 190 m 2 / g and especially preferably more than 210 m 2 / g. Furthermore, the N2SA is preferably less than 350 m 2 / g, preferably less than 320 m 2 / g and even more preferably less than 280 m 2 / g. In addition, the N2SA of silicon dioxide is measured using the measurement method described above.

[0114] An average primary particle size of silicon dioxide is preferably greater than 8 nm, more preferably greater than 10 nm, and even more preferably greater than 12 nm, considering the effects of the present invention. Furthermore, the 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. The average primary particle size of silicon dioxide is also measured using the measurement method described above.

[0115] For the purposes of the present invention, the silicon dioxide content based on 100 parts by mass of the rubber component is 130 parts by mass or more, preferably 135 parts by mass or more, more preferably 140 parts by mass or more, and even more preferably 150 parts by mass or more. Furthermore, for compatibility with an isoprene-based rubber, the 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.

[0116] From the perspective of the effects of the present invention, the silicon dioxide content in the fillers is preferably 55 wt% or more, more preferably 65 wt% or more, even more preferably 75 wt% or more, even more preferably 85 wt% or more, and particularly preferably 90 wt% or more. Furthermore, from the perspective of abrasion resistance, it is preferably 99 wt% or less, more preferably 97 wt% or less, and even more preferably 95 wt% or less. (Soot)

[0117] Examples of carbon black include, but are not limited to, N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, N762, and the like. A raw material for carbon black can be a biomass material, such as lignin, vegetable oil, and the like, or it can be pyrolysis oil obtained by pyrolyzing a used tire. Furthermore, a process for producing carbon black can be a combustion process, such as a furnace process, a process using hydrothermal carbonization (HTC), or a process using the pyrolysis of methane via a thermal carbon black process, and the like. Products from ASAHI CARBON CO., LTD., Cabot Japan KK, TOKAI CARBON CO., LTD., Mitsubishi Chemical Corporation, Lion Corporation, NIPPON STEEL Chemical & Material Co., Ltd., Columbia Carbon Corporation, etc., can be used as commercially available products.The soot can be used alone, or two or more of them can be used in combination.

[0118] Furthermore, as a carbon black other than the carbon black described above, carbon black from a biomass material, such as lignin and the like, or recovered carbon black obtained by pyrolysis of a carbon black-containing product, such as a tire and the like, and subsequently refined, can be used from the perspective of an environmental impact assessment, etc.

[0119] In this description, the term "recovered carbon black" refers to carbon black obtained by pulverizing a product such as a used tire containing carbon black and the like, and burning the pulverized product. After the product has undergone oxidative combustion by heating in air, the ratio of mass to ash (ash content), which is a non-combustible component, is 13% by mass or more according to a thermal weight measurement method of JIS K 6226-2:2003. That is, the ratio of mass (amount of carbon) to weight loss due to the oxidative combustion of the recovered carbon black is 87% by mass or less. The recovered carbon black can be expressed as rCB.

[0120] Recovered carbon black can be obtained from a pyrolysis process of a used pneumatic tire. EP 3427975 A, for example, describes, with reference to “Rubber Chemistry and Technology”, Vol. 85, No. 3, pages 408 to 449 (2012), in particular pages 438, 440 and 442, that the recovered carbon black can be obtained by pyrolysis at 550 to 800 °C in the absence of oxygen or by vacuum pyrolysis at a relatively low temperature of an organic material (

[0027] ). As described in

[0004] of JP 6856781 B, such carbon black obtained by the pyrolysis process typically lacks a functional group on its surface (A Comparison of Surface Morphology and Chemistry of Pyrolytic Carbon Blacks with Commercial Carbon Blacks, Powder Technology 160(2005) 190-193).

[0121] The recovered carbon black can be one lacking a functional group on its surface, or it can be one treated to contain a functional group on its surface. Treating the recovered carbon black to contain a functional group on its surface can be carried out by a conventional method. For example, in EP 3173251 A, carbon black obtained from a pyrolysis process is treated with potassium permanganate under acidic conditions, yielding carbon black containing a hydroxyl group and / or a carboxyl group on its surface. Furthermore, in JP 6856781 B, carbon black obtained from a pyrolysis process is treated with an amino acid compound containing at least one thiol group or disulfide group, yielding carbon black with an activated surface.Examples of recovered carbon black according to the present embodiment also include carbon black that is treated to contain a functional group on its surface.

[0122] The recovered carbon black can be that which is commercially available from Strebl Green Carbon Pte Ltd., LD Carbon, etc.

[0123] From the perspective of its amplifying properties, the specific nitrogen adsorption surface area (N2SA) of carbon black is preferably more than 70 m². 2 / g, preferably more than 90 m 2 / g, even more preferably more than 110 m 2 / g and especially preferably more than 130 m 2 / g. Furthermore, the N2SA is preferably less than 250 m from the perspectives of heat generation and processability. 2 / g, preferably less than 220 m 2 / g and even more preferably less than 190 m 2 / g. Furthermore, the N2SA of soot is measured using the measurement method described above.

[0124] The average primary particle size of 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 more than 8 nm, more preferably more than 10 nm, even more preferably more than 12 nm, and particularly preferably more than 14 nm. The average primary particle size of carbon black is also measured using the measurement method described above.

[0125] From the perspective of abrasion resistance, the carbon black content based on 100 parts by mass of the rubber component is preferably 1 part by mass or more, further 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, the content is preferably less than 50 parts by mass, more preferably less than 40 parts by mass, even more preferably less than 30 parts by mass, even more preferably less than 20 parts by mass, and particularly preferably less than 15 parts by mass. (Other fillers)

[0126] The fillers may contain a filler other than silicon dioxide and carbon black. The choice of filler is not particularly restricted, and it could include, for example, those conventionally and commonly used in the tire industry, such as aluminum hydroxide, calcium carbonate, alumina, clay, talc, and the like. These other fillers may be used alone, or two or more of them may be used in combination.

[0127] The total filler content F, based on 100 parts by mass of the rubber component in the rubber composition according to the present embodiment, is 130 parts by mass or more, preferably 135 parts by mass or more, more preferably 140 parts by mass or more, even more preferably 145 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, the filler 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. <silankupplungsmittel>

[0128] The silicon dioxide is preferably used in combination with a silane coupling agent. The silane coupling agent is not particularly restricted, and any silane coupling agent conventionally used in the tire industry in combination with silicon dioxide may be used. From the perspective that the desired effects can be obtained more readily, one or more silane coupling agents selected from the group consisting of a sulfide-based silane coupling agent and a mercapto-based silane coupling agent are preferred, and a mercapto-based silane coupling agent is further preferred.

[0129] Examples of sulfide-based silane coupling agents include bis(3-triethoxysilylpropyl)disulfide, bis(3-triethoxysilylpropyl)tetrasulfide, and the like. These sulfide-based silane coupling agents can be used alone, or two or more of them can be used in combination.

[0130] In the present invention, a mercapto-based silane coupling agent relates to a silane coupling agent comprising a mercapto group and to a silane coupling agent having a structure in which a mercapto group is protected by a protecting group. Examples of the mercapto-based silane coupling agent include, but are not specifically limited to, for example, a compound comprising a mercapto group represented by the following chemical formula (2), a compound comprising a mercapto group represented by the following chemical formula (3) is protected by esters, a compound comprising a bonding unit A represented by the following chemical formula (4) and / or a bonding unit B represented by the following chemical formula (5), and the like.Among these, the compound represented by the following chemical formula (3) or the compound comprising a bonding unit A represented by the following chemical formula (4) and / or a bonding unit B represented by the following chemical formula (5) is preferred, and the compound represented by the following chemical formula (3) is further preferred. These mercapto-based silane coupling agents can be used alone, or two or more of them can be used in combination. (where x represents an integer of 0 or more; y represents an integer of 1 or more; R.) 201 a hydrogen atom, an alkyl with 1 to 30 carbon atoms, an alkenyl with 2 to 30 carbon atoms, or an alkynyl with 2 to 30 carbon atoms (the alkyl, alkenyl, and alkynyl can be replaced by a halogen atom, hydroxyl, or carboxyl); and R 202 an alkylene with 1 to 30 carbon atoms, an alkenylene with 2 to 30 carbon atoms, or an alkynylene with 2 to 30 carbon atoms; where R 201 and R 202 (can form a ring structure.)

[0131] Examples of the compound represented by chemical formula (2) include, for example, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, a compound represented by the following chemical formula (6), etc. They can be used alone, or two or more of them can be used in combination.

[0132] Examples of the compound represented by chemical formula (3) include, for example, 3-octanoylthio-1-propyltriethoxysilane, 3-hexanoylthio-1-propyltriethoxysilane, 3-octanoylthio-1-propyltrimethoxysilane and the like.

[0133] An increase in the viscosity of the compound comprising bonding unit A represented by chemical formula (4) and / or bonding unit B represented by chemical formula (5) is suppressed during processing compared to a sulfide-based silane coupling agent, such as bis(3-triethoxysilylpropyl)tetrasulfide and the like. As a result, the dispersibility of silicon dioxide is improved, and fuel efficiency, wet adhesion performance, and elongation at break are thought to be further enhanced. This is believed to be due to the small increase in Mooney viscosity, since a sulfide portion of bonding unit A forms a CSC bond and is therefore thermally stable compared to tetrasulfide or disulfide.

[0134] To suppress an increase in viscosity during processing, the content of binding unit A is preferably 30 to 99 mol% and more preferably 50 to 90 mol%. Furthermore, the content of binding unit B is preferably 1 to 70 mol%, more preferably 5 to 60 mol%, and even more preferably 10 to 55 mol%. In addition, the combined content of binding unit A and binding unit B is preferably 95 mol% or more, more preferably 98 mol% or more, and most preferably 100 mol%. Moreover, the contents of binding unit A and binding unit B are amounts that also include a case in which binding units A and B are located at the ends of a silane coupling agent.One aspect of the case in which the bonding units A and B are located at the ends of the silane coupling agent is not particularly restricted, and it is sufficient that units corresponding to the chemical formulas (4) and (5) representing the bonding units A and B are formed.

[0135] In the compound comprising bonding unit A represented by chemical formula (4) and bonding unit B represented by chemical formula (5), the total number (x + y) of the number of repetitions of bonding unit A (x) and the number of repetitions of bonding unit B (y) preferably lies within a range of 3 to 300. If the total number of repetitions lies within this range, -C7H covers 15 The mercaptosilane of bonding unit A and bonding unit B are released. Therefore, a reduction in firing time can be suppressed, and good reactivity with silicon or a rubber component can be ensured.

[0136] Examples of the compound comprising bonding unit A represented by chemical formula (4) and / or bonding unit B represented by chemical formula (5) include, for example, NXT-Z30, NXT-Z45, NXT-Z60, and NXT-Z100, manufactured by Momentive Performance Materials, etc. They can be used individually, or two or more of them can be used in combination.

[0137] Examples of silane coupling agents other than sulfide-based and mercapto-based silane coupling agents include, but are not limited to, for example, a vinyl-based silane coupling agent such as vinyltriethoxysilane, vinyltrimethoxysilane, and the like; an amino-based silane coupling agent such as 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, and the like; a glycidoxy-based silane coupling agent such as γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and the like; a nitro-based silane coupling agent such as 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and the like; a chlorine-based silane coupling agent such as 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, and the like; and the like.These silane coupling agents, other than sulfide-based and mercapto-based silane coupling agents, can be used alone, or two or more can be used in combination. Examples of silane coupling agents that can be used include those listed above, such as those manufactured and sold by Momentive Performance Materials, Evonik Industries AG, etc.

[0138] The content of a silane coupling agent (preferably one or more silane coupling agents selected from the group consisting of a sulfide-based silane coupling agent and a mercapto-based silane coupling agent) based on 100 parts by mass of silicon dioxide is, from the perspective of enhancing the dispersibility of silicon dioxide, 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 perspective 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. <plastifizierungsmittel>

[0139] A plasticizer is a material that imparts plasticity to a rubber component and includes both liquid and solid plasticizers at 25°C. Examples of plasticizers include resin components, oils, liquid rubber, ester-based plasticizers, and the like. These plasticizers can be derived from mineral resources such as petroleum, natural gas, and the like; derived from biomass; or derived from naphtha recycled from a rubber or non-rubber product.Furthermore, low molecular weight hydrocarbon components obtained by pyrolyzing used tires or products containing various components and extracting them from the pyrolysate can be used as plasticizing agents. The rubber composition according to the present embodiment preferably comprises a resin component as a plasticizing agent and preferably includes, as the resin component, at least one selected from the group consisting of a C9-based resin, a dicyclopentadiene-based resin, and a terpene-based resin, and it is also preferred that it comprises a liquid resin. Furthermore, the rubber composition according to the present embodiment preferably comprises a liquid rubber, and it is also preferred that the rubber composition comprises a vegetable oil.The plasticizing agents can be used alone, or two or more of them can be used in combination. (resin component)

[0140] The rubber composition according to the present embodiment may include a resin component. The resin component that may be used in the present embodiment is not particularly restricted, and any resin commonly used in the tire industry may be used. Examples include, for instance, a C9-based resin, a C5-based resin, a C5 / C9-based resin, a dicyclopentadiene-based resin, an aromatic vinyl-based resin, a coumaron-based resin, an indene-based resin, a terpene-based resin, a rosin-based resin, a phenol-based resin, and the like. These resin components may be used individually, or two or more of them may be used in combination. Each resin component may also be used individually, or any two or more of them may be used in combination. <<Harz auf C9-Basis> >

[0141] A "C9-based resin" refers to a resin obtained by polymerizing C9 fractions and can be a polymer obtained by polymerizing a C9 fraction alone, or a copolymer obtained by copolymerizing a C9 fraction with other components. For example, a resin obtained by copolymerizing dicyclopentadiene (DCPD) with a C9 fraction is called a DCPD / C9 resin. Furthermore, a C9-based resin can be one obtained by hydrogenating or modifying it. Examples of C9 fractions include petroleum fractions with 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, coumaron, indene, methylindene, dicyclopentadiene, and the like. Examples of C9-based resins include those commercially available from BASF, Zeon Corporation, ENEOS Corporation, etc. <<Harz auf C5-Basis> >

[0142] A "C5-based resin" refers to a resin obtained by polymerizing C5 fractions, and can be one obtained by hydrogenating or modifying them. Examples of C5 fractions other than dicyclopentadiene include petroleum fractions with 4 to 5 carbon atoms, such as cyclopentadiene, isoprene, piperylene, 2-methyl-1-butene, 2-methyl-2-butene, 1-pentene, and the like. Examples of C5-based resins that can be used include those commercially available from STRUKTOL, Zeon Corporation, ENEOS Corporation, etc. <<Harz auf C5 / C9-Basis> >

[0143] A "C5 / C9-based resin" refers to a resin obtained by copolymerizing the C5 and C9 fractions, and can also be one obtained by hydrogenation or modification thereof. Examples of C5 / C9-based resins include those commercially available from Tosoh Corporation, Zibo Luhua Hongjin New Material Group Co., Ltd. <<Harz auf Dicyclopentadien-Basis> >

[0144] A "dicyclopentadiene-based resin" refers to a resin that contains cyclopentadiene (CPD) and / or dicyclopentadiene (DCPD) as the predominant monomer component and may be one obtained by hydrogenation or modification thereof. Examples of dicyclopentadiene-based resins include polymers obtained by polymerizing only dicyclopentadiene as a monomer, copolymers obtained by copolymerizing dicyclopentadiene with the C9 fraction (DCPD / C9 resin), and similar formulations. Examples of dicyclopentadiene-based resins that can be used include those commercially available from Exxon Mobil Corporation, ENEOS Corporation, Zeon Corporation, Maruzen Petrochemical Co., Ltd., etc. <<Aromatisches Harz auf Vinyl-Basis> >

[0145] An “aromatic vinyl-based resin” refers to a resin that incorporates an aromatic vinyl compound, such as styrene, α-methylstyrene, vinyltoluene, p-chlorostyrene, and the like, as a monomer component with the highest concentration, and may be one obtained by hydrogenation or modification thereof. A homopolymer of α-methylstyrene or styrene, or a copolymer of α-methylstyrene and styrene, is preferred as the aromatic vinyl-based resin, and a copolymer of α-methylstyrene and styrene is further preferred because it is economical, easy to process, and has excellent heat generation properties. Examples of commercially available aromatic vinyl-based resins include those from Kraton Corporation, Eastman Chemical Company, Mitsui Chemicals, Inc., etc. <<Harz auf Cumaron-Basis> >

[0146] A "coumaron-based resin" refers to a resin that includes coumaron as a monomer component and may be one obtained by hydrogenating or modifying it. Examples of preferred coumaron-based resins include a coumaron resin that is a polymer containing only coumaron as a monomer component, a coumaron-indene resin that is a copolymer containing coumaron and indene as monomer components, a coumaron-indene-styrene resin that is a copolymer containing coumaron, indene, and styrene as monomer components, and the like. Examples of suitable coumaron-based resins include those commercially available from Rutgers Chemicals, Nitto Chemical Co., Ltd., Mitsui Chemicals, Inc., etc. <<Harz auf Inden-Basis> >

[0147] An "indene-based resin" refers to a resin that includes indene as a monomer component and can be one obtained by hydrogenating or modifying it. Examples of indene-based resins include a coumaron-indene resin, which is a copolymer containing coumaron and indene as monomer components; a coumaron-indene-styrene resin, which is a copolymer containing coumaron, indene, and styrene as monomer components; and similar resins. Examples of indene-based resins that can be used include those commercially available from Rutgers Chemicals, Nitto Chemical Co., Ltd., Mitsui Chemicals, Inc., etc. <<Harz auf Terpen-Basis> >

[0148] A "terpene-based resin" refers to a resin that incorporates a terpene compound, such as α-pinene, β-pinene, limonene, dipentene, and the like, as a monomer component, and may be one obtained by hydrogenation or modification thereof. Preferred examples of terpene-based resins include a polyterpene resin, which is a polymer comprising only one or more of the terpene compounds as monomer components; an aromatically modified terpene resin, which is a copolymer comprising the terpene compound and an aromatic compound as monomer components; a terpenophenolic resin, which is a copolymer comprising the terpene compound and a phenolic compound as monomer components; and the like. Examples of aromatic compounds used as monomer components for aromatically modified terpene resins include styrene, α-methylstyrene, vinyltoluene, divinyltoluene, and the like.Examples of phenolic compounds used as monomer components for terpene phenolic resin include phenol, bisphenol A, cresol, xylenol, and the like. Terpene-based resins that can be used include those commercially available from companies such as Yasuhara Chemical Co., Ltd., Arakawa Chemical Industries, Ltd., and Nippon Terpene Chemicals, Inc. <<Harz auf Kolophonium-Basis> >

[0149] A "rosin-based resin" refers to a resin comprising a rosin acid compound, such as abietic acid, neoabietic acid, palustric acid, isopimaric acid, and the like, and may be one obtained by hydrogenation or modification thereof. Examples of rosin-based resins include, but are not limited to, natural resin rosin, rosin-modified resins obtained by modifying natural resin rosin through hydrogenation, disproportionation, dimerization, esterification, etc. Examples of rosin-based resins include those commercially available from Harima Chemicals Group, Inc., Arakawa Chemical Industries, Ltd., IREC Co., Ltd., etc. <<Harz auf Phenol-Basis> >

[0150] A "phenol-based resin" refers to a resin that incorporates a phenolic compound, such as phenol, cresol, and the like, as a monomer component, and may be one obtained by hydrogenation or modification thereof. Examples of phenol-based resins include, but are not limited to, phenol-formaldehyde resins, alkylphenol-formaldehyde resins, alkylphenol-acetylene resins, oil-modified phenol-formaldehyde resins, terpene phenol resins, and the like. Examples of phenol-based resins include those commercially available from Sumitomo Bakelite Co., Ltd., DIC Corporation, ASAHI YUKIZAI CORPORATION, etc. <<Flüssiges Harz> >

[0151] The resin component can be a liquid resin that is liquid at 25 °C. Examples of liquid resins include, but are not limited to, liquid resins such as a liquid aromatic vinyl resin, a liquid C9 resin, a liquid C5 / C9 resin, a liquid coumaron indene resin, and the like. These liquid resins can be used alone, or two or more of them can be used in combination.

[0152] The weight-average molecular weight (Mw) of a liquid resin is normally 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.

[0153] From the perspective of wet adhesion performance, the softening point of a resin component is preferably 60 °C or higher, more preferably 70 °C or higher, and even more preferably 80 °C or higher. Furthermore, from the perspective of processability and improved dispersibility of a filler in a rubber component, the softening point 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 also measured using the measurement method described above.

[0154] The content of a resin component based on 100 parts by mass of the rubber component (a total amount of all of several resin components when used in combination) is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, still more preferably 40 parts by mass or more, still more preferably 50 parts by mass or more, and particularly preferably 55 parts by mass or more. On the other hand, from the point of view of heat generation suppression, the content is preferably 100 parts by mass or less, more preferably 90 parts by mass or less, and still more preferably 80 parts by mass or less.

[0155] The total content of a C9-based resin, a dicyclopentadiene-based resin, and a terpene-based resin, based on 100 parts by mass of the rubber component, is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, still more preferably 40 parts by mass or more, still more preferably 50 parts by mass or more, and particularly preferably 55 parts by mass or more. On the other hand, from the perspective of heat generation suppression, the content is preferably 100 parts by mass or less, more preferably 90 parts by mass or less, and still more preferably 80 parts by mass or less. (Oil)

[0156] Examples of oils include mineral oils, vegetable oils, animal oils, and the like. Furthermore, from a life cycle assessment perspective, one can also be used that is obtained by refining used oil after its use in a rubber mixer or engine, or from used cooking oil used in a restaurant. The oils can be used individually, or two or more can be used in combination.

[0157] In this description, "mineral oil" refers to oil derived from mineral resources such as petroleum, natural gas, and the like. Examples of mineral oil include paraffinic oils (mineral oils), naphthenic oils, aromatic oils, and the like. Specific examples of mineral oils include, for example, Mild Extracted Solvate (MES), Distillate Aromatic Extract (DAE), Treated Distillate Aromatic Extract (TDAE), Treated Residual Aromatic Extract (TRAE), Residual Aromatic Extract (RAE), and the like. Additionally, as an environmental measure, oils that each have a low content of a polycyclic aromatic compound (PCA) may be used. Examples of oils that each have a low content of PCA include MES, TDAE, heavy naphthenic oil, and the like. The mineral oil may be used alone, or two or more may be used in combination.

[0158] In this description, examples of vegetable oils include, for instance, linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice bran oil, tall oil, sesame oil, perilla oil, castor oil, tung oil, pine oil, pine tar oil, sunflower oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, Japan wax, and the like. Furthermore, examples of vegetable oils also include refined oils obtained by refining the oils described above (cooking oils, etc.).), a transesterified oil obtained by transesterifying the oil described above, a hydrogenated oil obtained by hydrogenating the oil described above, a thermally polymerized oil obtained by thermally polymerizing the oil described above, an oxidized polymerized oil obtained by oxidizing the oils described above, a used cooking oil obtained by restoring what has been used as an edible oil, etc., and the like. Furthermore, the vegetable oil may be liquid or solid at 25 °C. The vegetable oil may be used alone, or two or more of them may be used in combination.

[0159] The vegetable oil according to the present embodiment preferably comprises acylglycerol and further preferably comprises triacylglycerol. In this description, acylglycerol also refers to a compound in which a hydroxyl group of glycerol and a fatty acid are ester-bound. The acylglycerol is not specifically restricted and may be 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, or triacylglycerol. Furthermore, the acylglycerol may be a monomer, a dimer, or a multimer that is a trimer or higher. Additionally, acylglycerol that is a dimer or higher may be obtained by thermal polymerization, oxidative polymerization, or the like. Furthermore, the acylglycerol may be liquid or solid at 25 °C.

[0160] Whether the rubber composition includes the acylglycerol described above can be determined by 1 The detection method can be verified by H-NMR measurement, but is not particularly limited. For example, a heavy chloroform into which a rubber composition containing triacylglycerol is immersed at 25 °C for 24 hours and then removed, 1 Subjected to ¹H NMR measurements at room temperature, signals near 5.26 ppm, near 4.28 ppm, and near 4.15 ppm were observed under a condition where the tetramethylsilane (TMS) signal was set to 0.00 ppm. It is suggested that these signals are derived from hydrogen atoms bonded to carbon atoms adjacent to oxygen atoms of the ester group. Furthermore, "near" in this paragraph is intended to represent a range of ±0.10 ppm.

[0161] The fatty acid described above is not particularly restricted and can be either an unsaturated or a saturated fatty acid. Examples of unsaturated fatty acids include monounsaturated fatty acids, such as oleic acid, and the like; and polyunsaturated fatty acids, such as linoleic acid, linolenic acid, and the like. Furthermore, examples of saturated fatty acids include butyric acid, lauric acid, and the like.

[0162] The desired fatty acid, as described above, is one with few double bonds, meaning a saturated or monounsaturated fatty acid, and oleic acid is preferred. A vegetable oil containing such a fatty acid could be, for example, a saturated or monounsaturated fatty acid, or a refined vegetable oil obtained through transesterification or similar processes. Furthermore, to produce a vegetable oil containing such a fatty acid, a plant can be improved through selective breeding, gene combination, genome editing, or similar methods.

[0163] Vegetable oils that can be used include, for example, those commercially available from Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo KK, ENEOS Corporation, Olisoy, H&R Group, HOKOKU Corporation, Fuji Kosan Co., Ltd., The Nisshin Oillio Group, etc.

[0164] Examples of animal oils include fish oils, beef tallow, oleyl alcohol derived from it, and the like.

[0165] When combined, the oil content, based on 100 parts by mass of the rubber component, is preferably 5 parts by mass or more, further preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, and particularly preferably 20 parts by mass or more, from the perspective of the effects of the present invention. Furthermore, the content is preferably 100 parts by mass or less, more preferably 80 parts by mass or less, and even more preferably 60 parts by mass or less. (Liquid rubber)

[0166] Liquid rubber is not particularly restricted as long as it is a polymer in a liquid state at 25 °C. Examples include liquid butadiene rubber (liquid BR), liquid styrene-butadiene rubber (liquid SBR), liquid isoprene rubber (liquid IR), liquid styrene-isoprene rubber (liquid SIR), liquid farnesene rubber, and the like. These liquid rubbers can be used individually, or two or more of them can be used in combination.

[0167] The weight-average molecular weight (Mw) of a liquid rubber 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 rubber is preferably 100 or more, more preferably 500 or more, more preferably 1,000 or more, more preferably 1,500 or more, and particularly preferably 2,000 or more. The effects of the present invention tend to be better preserved when the Mw of the liquid rubber is within the ranges described above. In addition, the liquid rubber is excluded from the examples of the rubber component in the present description.

[0168] The liquid rubber content, when combined, based on 100 parts by mass of the rubber component, is, from the perspective of the effects of the present invention, preferably 1 part by mass or more, more preferably 3 parts by mass or more, still more preferably 5 parts by mass or more, still more preferably 7 parts by mass or more, and particularly preferably 10 parts by mass or more. Furthermore, the content is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, still more preferably 30 parts by mass or less, and particularly preferably 25 parts by mass or less. (Ester-based plasticizer)

[0169] 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), diundecyl phthalate (DUP), dibutyl phthalate (DBP), dioctyl sebacate (DOS), tributyl phosphate (TBP), trioctyl phosphate (TOP), triethyl phosphate (TEP), trimethyl phosphate (TMP), thymidine triphosphate (TTP), tricresyl phosphate (TCP), trixylenyl phosphate (TXP), and the like. Ester-based plasticizers can be used alone, or two or more can be used in combination.

[0170] The content of a plasticizing agent based on 100 parts by mass of the rubber component (a total amount of all plasticizing agents when used in combination) is, from the perspective of wet adhesion performance, preferably 20 parts by mass or more, further preferably 30 parts by mass or more, even more preferably 40 parts by mass or more, and particularly preferably 50 parts by mass or more. Furthermore, from the perspective of processability, it is preferably 150 parts by mass or less, further preferably 140 parts by mass or less, even more preferably 130 parts by mass or less, and particularly preferably 120 parts by mass or less. <antioxidationsmittel>

[0171] Examples of the antioxidant include, but are not specifically limited to, a naphthylamine-based antioxidant such as phenyl-α-naphthylamine and the like; a diphenylamine-based antioxidant such as octylated diphenylamine, 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine and the like; an antioxidant based on p-phenylenediamine, such as N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (77PD), N,N'-diphenyl-p-phenylenediamine (DPPD), N,N'-ditolyl-p-phenylenediamine (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), N,N'-di-2-naphthyl-p-phenylenediamine (DNPD) and the like; an antioxidant based on quinoline, such as a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline and the like;A monophenol-based antioxidant, such as 2,6-di-t-butyl-4-methylphenol, styrenized phenol, and the like; a bisphenol-based, trisphenol-based, or polyphenol-based antioxidant, such as tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane and the like; and the like. Among these, the p-phenylenediamine-based antioxidant and the quinoline-based antioxidant are preferred, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline are further preferred. Commercially available products may include, for example, those manufactured by Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ouchi Shinko Chemical Industry Co., Flexsys, etc. The antioxidant can be used alone, or two or more of them can be used in combination.

[0172] The content of an antioxidant, when combined, based on 100 parts by mass of the rubber component (a total amount of all of several antioxidants when used in combination), is preferably 1.0 parts by mass or more, more preferably 2.0 parts by mass or more, still more preferably 3.0 parts by mass or more, still more preferably 3.5 parts by mass or more, and particularly preferably 4.0 parts by mass or more. Furthermore, the content is preferably 10 parts by mass or less, more preferably 8.0 parts by mass or less, and still more preferably 6.0 parts by mass or less. <Andere Verbindungsmittel>

[0173] The rubber composition according to the present embodiment may, in addition to the rubber component and the filler, suitably comprise bonding agents that are conventionally and commonly used in the tire industry, for example a vulcanized rubber particle, a processing aid, wax, stearic acid, zinc oxide, a vulcanizing agent, a vulcanization accelerator and the like. (Vulcanized rubber particle)

[0174] The vulcanized rubber particle is a particle made from vulcanized rubber. Specifically, a rubber powder specified in JIS K 6316:2017, and similar materials, can be used. Recycled rubber powder produced from a powdered end-of-life tire or similar material is preferred from both an environmental and cost perspective. The vulcanized rubber particle can be used individually, or two or more particles can be used in combination.

[0175] The vulcanized rubber particle is not particularly restricted and can be either unmodified or modified vulcanized rubber. Commercially available vulcanized rubber products, such as those manufactured by Lehigh Technologies, Muraoka Rubber Reclaiming Co., Ltd., etc., can be used.

[0176] The content of a vulcanized rubber particle, when bonded, based on 100 parts by mass of the rubber component, can, for example, be appropriately adjusted within a range of more than 1 part by mass and less than 80 parts by mass. (Processing aids)

[0177] Examples of processing aids include, for example, a fatty acid metal salt, a fatty acid amide, an amide ester, a silicon dioxide surfactant, a fatty acid ester, a mixture of a fatty acid metal salt and an amide ester, a mixture of a fatty acid metal salt and a fatty acid amide, and the like. Processing aids that can be used include, for example, those commercially available from Schill+Seilacher GmbH, Performance Additives, etc. The processing aid can be used alone, or two or more can be used in combination.

[0178] The content of the processing aid, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the perspective of improving processability. Furthermore, from the perspectives of abrasion resistance and fracture toughness, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Wax)

[0179] The type of wax is not particularly restricted, and any wax commonly used in the tire industry may be suitable. Examples include mineral-based waxes, plant-derived waxes, and the like. Mineral-based waxes refer to waxes derived from mineral resources such as oil, natural gas, and the like. Plant-derived waxes refer to waxes derived from natural resources such as plants and the like. Mineral-based waxes are preferred. Examples of plant-derived waxes include rice bran wax, carnauba wax, candelilla wax, and the like. Examples of mineral-based waxes include paraffin wax, microcrystalline wax, a specially selected wax of these, and the like, with paraffin wax being preferred.Furthermore, according to the present embodiment, the wax should not contain stearic acid. For example, waxes commercially available from Ouchi Shinko Chemical Industry Co., Nippon Seiro Co., Ltd., PARAMELT, etc., can be used. The wax can be used alone, or two or more can be used in combination.

[0180] The wax content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the perspective of improving the weather resistance of the rubber. Furthermore, from the perspective of preventing whitening of a tire due to blooming, it is preferably less than 10 parts by mass, more preferably less than 7.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Stearic acid)

[0181] The stearic acid content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the point of view of processability. Furthermore, from the point of view of vulcanization rate, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Zinc oxide)

[0182] The zinc oxide content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the point of view of processability. Furthermore, from the point of view of abrasion resistance, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Vulcanizing agent)

[0183] Sulfur is suitable for use as a vulcanizing agent. Powdered sulfur, oil-processing sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, highly dispersible sulfur, and similar forms can be used.

[0184] When combined as a vulcanizing agent, the sulfur content, based on 100 parts by mass of the rubber component, is preferably more than 0.1 parts by mass, more preferably more than 0.5 parts by mass, and even more preferably more than 1.0 parts by mass, to ensure a sufficient vulcanization reaction. Furthermore, to prevent deterioration, it is preferably less than 5.0 parts by mass, more preferably less than 3.0 parts by mass, and even more preferably less than 2.0 parts by mass. Additionally, when an oil-based sulfur is used as the vulcanizing agent, the vulcanizing agent content is defined as the total content of pure sulfur contained in the oil-based sulfur.

[0185] A well-known organic crosslinking agent can also be used as a vulcanizing agent other than sulfur. While the choice of organic crosslinking agent is not particularly limited, as long as it can form a crosslinking chain other than polysulfide bonds, examples of organic crosslinking agents include alkylphenol-sulfur chloride condensate, sodium hexamethylene 1,6-bisthiosulfate dihydrate, 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane, dicumyl peroxide, and the like. These organic crosslinking agents can include those commercially available from Taoka Chemical Co., Ltd., LANXESS, Flexsys, etc. (Vulcanization accelerator)

[0186] Examples of vulcanization accelerators include, but are not limited to, sulfenamide-based, thiazole-based, guanidine-based, thiuram-based, thiourea-based, dithiocarbamic acid salt-based, aldehyde-amine-based, aldehyde-ammonia-based, imidazoline-based, xanthate-based, caprolactam disulfide, and the like. These vulcanization accelerators can be used individually, or two or more can be used in combination.Among these, one or more vulcanization accelerators selected from the group consisting of a sulfenamide-based vulcanization accelerator, a thiazole-based vulcanization accelerator, and a guanidine-based vulcanization accelerator are preferred, given that the desired effects can be obtained more appropriately.

[0187] Examples of sulfenamide-based vulcanization accelerators include, for example, N-tert-butyl-2-benzothiazolylsulfenamide (TBBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N,N-dicyclohexyl-2-benzothiazolylsulfenamide (DCBS) and the like.

[0188] Examples of thiazole-based vulcanization accelerators include, for example, 2-mercaptobenzothiazole (MBT) or salts thereof, di-2-benzothiazolyl disulfide (MBTS), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(2,6-diethyl-4-morpholinothio)benzothiazole, and the like. Among these, MBTS and MBT are preferred, and MBTS is further preferred.

[0189] Examples of guanidine-based vulcanization accelerators include, for example, 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, di-o-tolylguanidine salt of dicatechol borate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, 1,3-di-o-cumenyl-2-propionylguanidine and the like.

[0190] The content of a vulcanization accelerator, when combined, based on 100 parts by mass of the rubber component (a total amount of all vulcanization accelerators when used in combination), is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass or more, more preferably 2.0 parts by mass or more, more preferably 3.0 parts by mass or more, and most preferably 4.0 parts by mass or more, to ensure a sufficient vulcanization rate. Furthermore, the content of the vulcanization accelerator is preferably 10 parts by mass or less, and more preferably 7.0 parts by mass or less, to suppress blooming.

[0191] In the present description, various materials, each containing a single carbon atom (for example, rubber, oil, resin, vulcanization accelerator, antioxidant, surfactant, and the like), can be derived from carbon dioxide in the atmosphere. These various materials can be obtained by directly converting carbon dioxide or by converting methane, which is obtained via a process of methanation, in which methane is synthesized from carbon dioxide. [Production]

[0192] The rubber composition according to the present embodiment can be produced by a known method. It can be produced, for example, by kneading the respective components described above using a rubber kneading machine, such as an open roller, a closed-type kneader (a Banbury mixer, a kneader, and the like), and the like.

[0193] The kneading step includes, for example, a basic kneading step involving the kneading of bonding agents and additives other than a vulcanizing agent and vulcanization accelerator; and a final kneading step (F-kneading) involving the addition of the vulcanizing agent and vulcanization accelerator to the kneaded product obtained in the basic kneading step, and the kneading of this product. Furthermore, the basic kneading step can also be subdivided into several steps if necessary.In a case where the basic kneading step is subdivided, a method of subdividing the basic kneading step may be: (1) a method of first kneading a portion of the binders and additives into a masterbatch and then adding the remaining binders and additives to the resulting masterbatch for kneading; (2) a method of kneading all the binders and additives to be kneaded in the basic kneading step at once and then rolling the kneaded product once or several times; or the like. In method (1) described above, the number of masterbatches is not limited and may be two or more. Furthermore, if the number of masterbatches is two or more, all the binders and additives used in the basic kneading step may be allocated to any one of the masterbatches.

[0194] Examples of kneading conditions include, but are not specifically limited to, for example, a process of kneading at a discharge temperature of 150 °C to 170 °C for 3 to 10 minutes for the initial kneading step and kneading at 70 °C to 110 °C for 1 to 5 minutes for the final kneading step. Examples of vulcanization conditions include, but are not specifically limited to, for example, a process of vulcanizing at 150 °C to 200 °C for 10 to 30 minutes.

[0195] The tire according to the present embodiment, which comprises a tread made of the rubber composition described above, can be produced by a conventional method. That is, the tire can be produced by extruding an unvulcanized rubber composition, prepared by combining the components described above as required for a rubber component, into a tread mold, by assembling the tread thus obtained together with other tire elements on a tire molding machine, and by forming it into an unvulcanized tire by a conventional method, followed by heating and pressurizing the unvulcanized tire thus obtained in a vulcanizing machine.Examples of vulcanization conditions include, but are not specifically limited to, for example, a process of vulcanizing at 150 °C to 200 °C for 10 to 30 minutes. [Application]

[0196] The tire according to the present embodiment can be used for any application, regardless of whether it is a pneumatic or deflated tire, and can be used as a passenger car tire, a large passenger car tire, a large SUV tire, a racing tire, a motorcycle tire, a heavy-duty tire, or a run-flat tire. Furthermore, a passenger car tire refers to a tire intended for mounting on a four-wheeled vehicle and having a maximum load capacity of less than 1400 kg. A heavy-duty tire refers to a tire with a maximum load capacity of 1400 kg or more.Furthermore, according to the present embodiment, the tire can be used as an all-season tire, a summer tire, and a winter tire, such as a spikeless tire and the like. EXAMPLES

[0197] Examples are described below that are considered preferred in the implementation of the present invention (examples), although the scope of protection of the present invention is not limited to these examples. Results calculated on the basis of the evaluation methods described below, taking into account a tire obtained in accordance with Tables 1-1 to 2 using various chemicals described below, are shown in Tables 1-1 to 2. <Verschiedene Chemikalien>

[0198] The chemicals used in the examples and comparative examples are shown collectively below. IR-based rubber: TSR 20 (NR) SBR 1: Tufdene 2000R, manufactured by Asahi Kasei Corporation (S-SBR, styrene content: 25 wt%, vinyl content: 13 mol%, Tg: -65 °C, Mw: 450,000, not oil-diluted) SBR 2: F1810, manufactured by LG Chem. (S-SBR, styrene content: 18 wt%, vinyl content: 10 mol%, Tg: -73 °C, comprising 5.0 wt parts of an expanded oil content based on 100 wt parts of a rubber solids content) BR: Ubepol BR (registered trademark) 150B, manufactured by UBE Corporation (unmodified BR, cis content: 97 mol%, Mw: 440,000) Soot 1: Show Black N134, manufactured by Cabot Japan KK (N2SA: 148 m 2 / g, average primary particle size: 18 nm) Soot 2: Show Black N220, manufactured by Cabot Japan KK (N2SA: 115 m 2 / g, average primary particle size: 22 nm) Silicon dioxide 1: Ultrasil 9100GR, manufactured by Evonik Industries AG (CTAB-specific surface area: 200 m²) 2 / g, N2SA: 235 m 2 / G) Silicon dioxide 2: Zeosil Premium SW, manufactured by Solvay (CTAB-specific surface area: 245 m²) 2 / g, N2SA: 258 m 2 / G) Silane coupling agent 1: Si266, manufactured by Evonik Industries AG (Bis(3-triethoxysilylpropyl)disulfide) Silane coupling agent 2: NXT, manufactured by Evonik Industries AG (3-Octanoylthio-1-propyltriethoxysilane) Resin component 1: SYLVATRAXX4401, manufactured by Kraton Corporation (copolymer of α-methylstyrene and styrene, softening point: 85 °C) Resin component 2: SYLVATARAXX4150, manufactured by Kraton Corporation (polyterpene resin, softening point: 115 °C) Resin component 3: Oppera PR383, manufactured by Exxon Mobil Chemical (hydrogenated DCPD / C9 resin, softening point: 103 °C) Oil 1: VivaTec 500, manufactured by H&R Group (TDAE oil) Oil 2: Sunflower oil, produced by The Nisshin Oillio Group (Oleic acid content: 55% by mass, Total polyunsaturated fatty acid content: 8% by mass) Liquid resin: Ricon 340, manufactured by Cray Valley (C5 / C9-based liquid resin, Mw: 2400) Wax: OZOACE 0355, manufactured by Nippon Seiro Co., Ltd. (paraffin wax) Antioxidant 1: Nocrac 6C, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine) Antioxidant 2: Nocrac RD, manufactured by Ouchi Shinko Chemical Industry Co., Ltd., (Poly(2,2,4-trimethyl-1,2-dihydroquinoline)) Processing aid: WB16, manufactured by STRUKTOL (mixture of calcium soap and fatty acid amide) Stearic acid: Stearic acid “CAMELLIA”, manufactured by NOF CORPORATION Zinc oxide: Zinc oxide No. 1, manufactured by Mitsui Mining & Smelting Co., Ltd. Sulfur: Powdered sulfur, manufactured by Tsurumi Chemical Industry Co., Ltd. Vulcanization accelerator 1: Nocceler CZ, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-Cyclohexyl-2-benzothiazolylsulfenamide (CBS)) Vulcanization accelerator 2: Nocceler D, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (1,3-Diphenylguanidine (DPG)) (Examples and comparisons)

[0199] According to the compound formulations shown in Tables 1-1 to 2, using a closed 1.7-liter Banbury mixer, all chemicals other than sulfur and vulcanization accelerators are kneaded for 1 to 10 minutes until a discharge temperature of 150 to 160 °C is reached to obtain a kneaded product. Next, using an open twin-screw mixer, sulfur and the vulcanization accelerators are added to the kneaded product, and the mixture is kneaded for 4 minutes until the temperature reaches 105 °C to obtain an unvulcanized rubber composition.The unvulcanized rubber compound is used to extrude a tread mold using an extruder equipped with a pre-shaped die. This tread is then combined with other tire elements to create an unvulcanized tire. The unvulcanized tire is then vulcanized at 170°C to produce each test tire (size in Tables 1-1 to 1-3: 205 / 65R15, size in Table 2: 175 / 65R14). The tire weight (G) is 8.4 kg for tires in Tables 1-1 to 1-3 with a size of 205 / 65R15 and 6.5 kg for tires in Table 2 with a size of 175 / 65R14. Furthermore, the maximum load capacity (W) is... L For the tires in Tables 1-1 to 1-3, the weight is 660 kg, and for the tires in Table 2, it is 515 kg. Therefore, G / W L Each test tire in tables 1-1 to 1-3 has a G / W of 0.0127. L The value for each test tire in Table 2 is 0.0126. <Messung von durch Aceton extrahierbarer (AE) Menge>

[0200] An AE quantity is measured for each rubber test piece produced by cutting it from the tread of each test tire. The AE quantity can be calculated using the following equation after immersing each test piece in acetone for 72 hours to extract a soluble component, and after measuring the mass of each test piece before and after extraction. (Amount extractable by acetone (%) = {(Mass of vulcanized rubber test piece before extraction - Mass of vulcanized rubber test piece after extraction) (Mass of vulcanized rubber test piece extraction)} × 100. <Lenkstabilität während Hochgeschwindigkeitslauf>

[0201] Each test tire is mounted on all wheels of a vehicle (a domestic FF vehicle with a 2000cc engine), and actual vehicle driving is conducted by having the vehicle complete 10 laps at approximately 120 km / h on a test track with a dry asphalt surface. During this test, twenty drivers perform sensory evaluations of body roll during corner entry, turn-in, and corner exit. The evaluations are performed using integer values ​​from 1 to 5 points (less roll means a higher score), and a total score from the twenty drivers is calculated.A total score from a reference comparison example (comparison examples 1 in Tables 1-1 to 1-3, comparison example 4 in Table 2) is converted into a reference value (100), and a rating result for each test tire is given as an index relative to the total score. The results show that the higher the index, the better the steering stability during high-speed driving. Table 1-1 (Tire size: 205 / 65R15) Example 1 2 3 4 5 6 Composite quantity (mass parts) IR-based rubber 40 40 70 40 50 40 SBR 1 20 30 30 - - - SBR 2 - - - 47,25 47,25 57,75 (solid content) - - - (45) (45) (55) BR 40 30 - 15 5 5 Soot 1 10 10 10 10 10 10 Silicon dioxide 1 130 130 130 130 135 135 Silicon dioxide 2 - - - - - - Silane coupling agent 1 13 13 13 - - - Silane coupling agent 2 - - - 13 - 13,5 13,5 - Resin component 1 20 30 30 55 - - Resin component 2 - - - - 55 - Resin component 3 - - - - - 55 Öl 1 50 40 40 10 15 15 Liquid resin - - - - - - wax 2,5 2,5 2,5 2,5 2,5 2,5 Antioxidant 1 3,0 3,0 3,0 3,0 3,0 3,0 Antioxidants 2 1,5 1,5 1,5 1,5 1,5 1,5 Processing aids 2, 0 2,0 2,0 2,0 2,0 2,0 Composite quantity (mass parts) Stearic acid 2,0 2,0 2,0 2,0 2 0 2,0 zinc oxide 2,0 2,0 2,0 2,0 2,0 2,0 sulfur 1,2 1,2 1,2 1,2 1,2 1,2 Vulcanization accelerator 1 2,5 2, 5 2,5 2,5 2,5 2,5 Vulcanization accelerator 2 2,0 2,0 2,0 2,0 2,0 2,0 Styrene content of SBR (mass %) 25 25 25 18 18 18 Total content F of fillers (parts by mass) 140 140 140 140 145 145 CTAB-specific surface area C of silicon dioxide (m 2 / G) 200 200 200 200 200 200 Acetone extractable quantity AE (mass %) 25,12 25,09 25,22 25,11 25,88 25,77 Thickness T of running surface (mm) 16, 0 16, 0 16, 0 16, 0 16,0 16, 0 T / F 0, 11 0, 11 0, 11 0, 11 0,11 0,11 F × AE 3517 3513 3531 3515 3753 3737 T × AE 402 401 404 402 414 412 T / C 0, 08 0, 08 0, 08 0, 08 0,08 0, 08 Steering stability during high-speed running 125 125 120 130 145 130 Table 1-2 (Tire size: 205 / 65R15) Example 7 8 9 10 11 12 13 Composite quantity (mass parts) IR-based rubber 40 40 40 40 55 40 50 SBR 1 - - - - - - - SBR 2 47,25 47,25 47,25 47,25 47,25 63 47,25 (solid content) (45) (45) (45) (45) (45) (60) (45) BR 15 15 15 15 - - 5 Soot 1 10 10 10 10 10 10 10 Silicon dioxide 1 135 180 - - - - - Silicon dioxide 2 - - 130 160 150 150 150 Silane coupling agent 1 - - - - - - - Silane coupling agent 2 13,5 18 13 16 15 15 15 Resin component 1 20 40 55 55 - - 20 Resin component 2 40 40 - - 55 - 40 Resin component 3 - - - 10 - 55 - Öl 1 10 35 15 35 35 35 20 Liquid resin - - - - - - 10 wax 2,5 2,5 2,5 2,5 2,5 2,5 2,5 Antioxidant 1 3,0 3,0 3,0 3,0 3,0 3,0 3,0 Antioxidants 2 1,5 1,5 1,5 1,5 1,5 1,5 1,5 Processing aids 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Composite quantity (mass parts) Stearic acid 2,0 2,0 2,0 2,0 2,0 2,0 2,0 zinc oxide 2,0 2,0 2,0 2,0 2,0 2,0 2,0 sulfur 1,2 1,2 1,2 1,2 1,2 1,2 1,2 Vulcanization accelerator 1 2,5 2,5 2,5 2,5 2,5 2,5 2,5 Vulcanization accelerator 2 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Styrene content of SBR (mass %) 18 18 18 18 18 18 18 Total content F of fillers (parts by mass) 145 190 140 170 160 160 160 CTAB-specific surface area C of silicon dioxide (m 2 / G) 200 200 245 245 245 245 245 Acetone extractable quantity AE (mass %) 25,84 30,83 26,19 29, 77 28,77 28,62 28,75 (Thickness T of tread (mm)) 16,0 16,0 16,0 16,0 16,0 16,0 16,0 T / F 0,11 0,08 0,11 0,09 0,10 0,10 0,10 F × AE 3747 5858 3667 5061 4603 4579 4600 T × AE 413 493 419 476 460 458 460 T / C 0,08 0,08 0,07 0,07 0,07 0,07 0,07 Steering stability during high-speed running 135 150 140 155 160 150 155 Table 1-3 (Tire size: 205 / 65R15) Comparative example 1 2 3 Composite quantity (mass parts) IR-based rubber 40 40 40 SBR 1 - - - SBR 2 47,25 47,25 47,25 (solid content) (45) (45) (45) BR 15 15 15 Soot 1 10 10 40 Silicon dioxide 1 65 95 65 Silicon dioxide 2 - - - Silane coupling agent 1 - - - Silane coupling agent 2 6, 5 6, 5 6,5 Resin component 1 15 15 15 Resin components 2 - - - Resin component 3 - - - Öl 1 10 40 40 Liquid resin - - - wax 2,5 2,5 2,5 Antioxidant 1 3, 0 3, 0 3, 0 Antioxidants 2 1,5 1,5 1,5 Processing aids 2, 0 2, 0 2, 0 Composite quantity (mass parts) Stearic acid 2, 0 2, 0 2, 0 zinc oxide 2, 0 2, 0 2, 0 sulfur 1, 2 1, 2 1, 2 Vulcanization accelerator 1 2,5 2,5 2,5 Vulcanization accelerator 2 2, 0 2, 0 2, 0 Styrene content of SBR (mass %) 18 18 18 Total content F of fillers (parts by mass) 75 105 105 CTAB-specific surface area C of silicon dioxide (m 2 / G) 200 200 200 Acetone extractable quantity AE (mass %) 18,84 25, 44 25,34 Thickness T of running surface (mm) 16, 0 16,0 16, 0 T / F 0, 21 0,15 0,15 F × AE 1413 2671 2661 T × AE 301 407 405 T / C 0, 08 0, 08 0, 08 Steering stability during high-speed running 100 95 80 Table 2 (Tire size: 175 / 65R14) Example Comparative example 14 15 16 4 Composite quantity (mass parts) IR-based rubber 40 40 40 40 SBR 1 - - - - SBR 2 47,25 47,25 57,75 47,25 (solid content) (45) (45) (55) (45) BR 15 15 - 15 Soot 2 10 10 10 10 Silicon dioxide 1 130 180 50 65 Silicon dioxide 2 - - 135 - Silane coupling agent 1 - - - - Silane coupling agent 2 13 18 18 6, 5 Resin component 1 - 40 - 15 Resin component 2 55 40 40 - Resin component 3 - - 40 - Öl 2 10 15 20 10 Liquid resin - 20 20 - wax 2,5 2,5 2,5 2,5 Antioxidant 1 3,0 3,0 3, 0 3, 0 Antioxidants 2 1,5 1,5 1,5 1,5 Processing aids 2,0 2,0 2, 0 2,0 Example Comparative example 14 15 16 4 Composite quantity (mass parts) Stearic acid 2,0 2,0 2, 0 2, 0 zinc oxide 2,0 2,0 2, 0 2,0 sulfur 1,2 1,2 1,2 1,2 Vulcanization accelerator 1 2,5 2,5 2,5 2,5 Vulcanization accelerator 2 2,0 2,0 2, 0 2,0 Styrene content of SBR (mass %) 18 18 18 18 Total content F of fillers (parts by mass) 140 190 195 75 CTAB-specific surface area C of silicon dioxide (m 2 / G) 200 200 233 200 Amount of AE extractable by acetone (mass %) 25,11 30,83 31,53 18,84 Thickness T of running surface (mm) 12,0 12,0 12,0 12,0 T / F 0,09 0,06 0, 06 0, 16 F × AE 3515 5858 6148 1413 T × AE 301 370 378 226 T / C 0,06 0,06 0,05 0, 06 Steering stability during high-speed running 135 150 145 100 <Ausführungsformen>

[0202] Examples of embodiments of the present invention are described below. [1] A tire that includes a tread, the running surface is made up of a rubber composition comprising a rubber component and fillers, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, where the content of isoprene-based rubber in the rubber component is 40% by mass or more, where the glass transition temperature Tg of the styrene-butadiene rubber is -60 °C or lower, the fillers contain silicon dioxide, wherein the rubber composition comprises 130 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component, and where the T / F ratio is less than 0.16, where T represents a thickness in mm of the running surface and F represents a total filler content in parts by mass based on 100 parts by mass of the rubber component in the rubber composition. [2] The tire of [1] above, wherein the rubber composition comprises 150 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component. [3] The tire of [1] or [2] above, wherein a CTAB-specific surface C of silicon dioxide 190 m 2 / g or more and preferably 200 m 2 / g or more. [4] The tire of [1] above, wherein the rubber composition comprises 50 parts by mass or more, preferably 55 parts by mass or more of a resin component based on 100 parts by mass of the rubber component. [5] The tire of one of [1] to [4] above, wherein the styrene content of the styrene-butadiene rubber is 20 wt% or more. [6] The tire from one of [1] to [5] above, wherein an amount of AE extractable by acetone in mass % of the rubber composition is 25.0 or more. [7] The tire of [4] above, wherein the resin component comprises at least one selected from the group consisting of a C9-based resin, a dicyclopentadiene-based resin and a terpene-based resin. [8] The tire of one of [1] to [7] above, wherein the rubber composition comprises a mercapto-based silane coupling agent. [9] The tire of [4] above, wherein the resin component comprises a liquid resin.

[10] The tire of one of [1] to [9] above, wherein the rubber composition comprises a liquid rubber.

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

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

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

[11] above, wherein F × AE is greater than 3500 and preferably greater than 3600, where AE represents an amount extractable by acetone in mass % of the rubber composition.

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

[12] above, wherein T × AE is greater than 400, preferably greater than 410 and further preferably greater than 420, where AE represents an amount extractable by acetone in mass % of the rubber composition.

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

[13] above, wherein T / C is less than 0.10 and preferably less than 0.09, where C is a CTAB-specific surface area in m² 2 represents / g of silicon dioxide.

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

[14] above, where G / W L 0.0170 or less, preferably 0.0165 or less, further preferably 0.0160 or less and still more preferably 0.0150 or less, where W L where G represents the maximum load capacity of the tire in kg and G represents the weight of the tire in kg. REFERENCE MARK LIST 1. Tread surface 2 circumferential grooves 6 first shift 7 second shift T Thickness of tread surface CL tire equator QUOTES INCLUDED IN THE DESCRIPTION

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

[0000] JP 2021-25006 A

[0002] JP 2009-2594 A

[0111] EP 3427975 A

[0120] JP 6856781 B [0120, 0121] EP 3173251 A

[0121] Cited non-patent literature

[0000] Akita Prefectural University Web Journal B / 2019, Vol. 6, pp. 216-222

[0111] A Comparison of Surface Morphology and Chemistry of Pyrolytic Carbon Blacks with Commercial Carbon Blacks, Powder Technology 160(2005) 190-193

[0120] < / antioxidationsmittel> < / plastifizierungsmittel> < / silankupplungsmittel> < / kautschukkomponente> < / t> < / definitionen>

Claims

A tire comprising a tread, wherein the tread is composed of a rubber composition comprising a rubber component and fillers, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, wherein the content of the isoprene-based rubber in the rubber component is 40% by mass or more, wherein the glass transition temperature Tg of the styrene-butadiene rubber is -60°C or lower, wherein the fillers include silicon dioxide, wherein the rubber composition comprises 130 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component, and wherein the ratio T / F is less than 0.16, where T represents a thickness in mm of the tread and F represents a total filler content in parts by mass based on 100 parts by mass of the rubber component in the rubber composition. Tires according to claim 1, wherein the rubber composition comprises 150 parts by mass or more of silicon dioxide based on 100 parts by mass of the rubber component. Tires according to claim 1 or 2, wherein a CTAB-specific surface area C of the silicon dioxide is 190 m2 / g or more. Tires according to claim 1, wherein the rubber composition comprises 50 parts by mass or more of a resin component based on 100 parts by mass of the rubber component. Tires according to any one of claims 1 to 4, wherein the styrene content of the styrene-butadiene rubber is 20% by mass or more. Tires according to any one of claims 1 to 5, wherein an amount of AE extractable by acetone in mass % of the rubber composition is 25.0 or more. Tires according to claim 4, wherein the resin component comprises at least one selected from the group consisting of a C9-based resin, a dicyclopentadiene-based resin and a terpene-based resin. Tires according to any one of claims 1 to 7, wherein the rubber composition comprises a mercapto-based silane coupling agent. Tires according to claim 4, wherein the resin component comprises a liquid resin. Tires according to any one of claims 1 to 9, wherein the rubber composition comprises a liquid rubber. Tires according to any one of claims 1 to 10, wherein the rubber composition comprises a vegetable oil. Tires according to any one of claims 1 to 11, wherein F × AE is greater than 3500, where AE represents an amount extractable by acetone in mass % of the rubber composition. Tires according to any one of claims 1 to 12, wherein T × AE is greater than 400, where AE represents an amount extractable by acetone in mass % of the rubber composition. Tires according to any one of claims 1 to 13, wherein T / C is less than 0.10, where C represents a CTAB-specific surface area in m2 / g of silicon dioxide. Tires according to any one of claims 1 to 14, wherein G / WL is 0.0170 or less, where WL represents the maximum load capacity in kg of the tire and G represents the weight in kg of the tire.

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