Tire

Abstract

To provide a tire which can improve total performance of steering stability performance when traveling at high speed and anti-wear performance.SOLUTION: A tire includes a tire member composed of a rubber composition, wherein the rubber composition contains a rubber component, a filler, and a plasticizer, the rubber component contains isoprene-based rubber and styrene-butadiene rubber, the isoprene-based rubber contains epoxidized isoprene-based rubber, and when the total content of the isoprene-based rubber in the rubber component is represented by N (mass%), and a thickness of the tire member is represented by t (mm), N / t is less than 2.2.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tire. [Background technology]

[0002] Patent Document 1 describes that a tire having a tread made of a rubber composition that contains isoprene-based rubber and silica and has 20°C tan δ and -20°C tan δ within a predetermined range exhibits a balanced improvement in fuel economy, wear resistance, handling stability at high speeds, and wet grip performance at high speeds. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-25006 Summary of the Invention [Problem to be solved by the invention]

[0004] When an isoprene-based rubber and a styrene-butadiene rubber are used in combination to improve grip performance, silica tends to be unevenly distributed in the styrene-butadiene rubber phase, making it difficult to ensure the dispersibility of silica, and therefore there is room for improvement in each tire performance.

[0005] An object of the present invention is to provide a tire that can improve overall performance, including steering stability during high-speed driving and wear resistance. [Means for solving the problem]

[0006] The present invention relates to a tire having tire components made of a rubber composition, wherein the rubber composition contains a rubber component, a filler, and a plasticizer, the rubber component contains an isoprene-based rubber and a styrene-butadiene rubber, the isoprene-based rubber contains an epoxidized isoprene-based rubber, and where N (mass%) is the total content of the isoprene-based rubber in the rubber component and t (mm) is the thickness of the tire component, the tire has an N / t ratio of less than 2.2. [Effects of the Invention]

[0007] According to the present invention, a tire is provided that can improve the overall performance of steering stability during high-speed driving and wear resistance. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic partial cross-sectional view of a tire according to one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] A tire according to one embodiment of the present invention is a tire having tire components made of a rubber composition, wherein the rubber composition contains a rubber component, a filler, and a plasticizer, the rubber component includes an isoprene-based rubber and a styrene-butadiene rubber, and the isoprene-based rubber includes an epoxidized isoprene-based rubber, and where N (mass%) is the total content of the isoprene-based rubber in the rubber component and t (mm) is the thickness of the tire component, the tire has an N / t ratio of less than 2.2.

[0010] Although not intending to be bound by theory, the mechanism by which the overall performance of steering stability during high-speed driving and wear resistance is improved in the tire of the present invention is thought to be, for example, as follows.

[0011] (1) Because epoxidized isoprene rubber interacts with silica, it has higher rigidity than ordinary isoprene rubber, which is thought to contribute to improved handling stability.

[0012] In addition, (2) since epoxidized isoprene rubber and styrene-butadiene rubber are partially compatible with each other, it is expected that the dispersibility of the filler will be improved, which is thought to contribute to improved abrasion resistance.

[0013] It is believed that the cooperation of the above (1) and (2) will achieve the remarkable effect of improving the overall performance of steering stability and wear resistance during high-speed driving.

[0014] The total content N of the isoprene-based rubber in the rubber component is preferably more than 5% by mass, from the viewpoint of ensuring the rigidity of the rubber composition.

[0015] From the viewpoint of the effects of the present invention, the rubber component preferably contains more than 30% by mass of styrene-butadiene rubber.

[0016] From the viewpoint of the effects of the present invention, the total amount of styrene in the rubber component is preferably less than 30% by mass.

[0017] The plasticizer preferably contains a dicyclopentadiene resin, which is highly compatible with isoprene rubber and styrene-butadiene rubber and is bulky, and therefore it is believed that a rubber composition using these in combination can be easily imparted with flexibility without impairing the reinforcing effect.

[0018] When the total content of the plasticizers relative to 100 parts by mass of the rubber component is represented by P (parts by mass), P / N is preferably more than 2.0 in view of the effects of the present invention.

[0019] When the content of silica relative to 100 parts by mass of the rubber component is X (parts by mass) and the content of styrene-butadiene rubber in the rubber component is S (% by mass), from the viewpoint of the effects of the present invention, it is preferable that X / S is greater than 1.0.

[0020] From the viewpoint of building a sustainable society, the silica is preferably silica made from biomass materials.

[0021] From the viewpoint of effectively exerting the effects of the present invention, the tire component is preferably at least one selected from the group consisting of a tread portion, a sidewall, and a clinch.

[0022] <Definition> The "tread portion" refers to a component that includes the portion that forms the tire's contact surface, and in the case where the tire includes components that form the tire skeleton from steel or textile materials, such as a belt layer, a belt reinforcing layer, and a carcass layer, the "tread portion" is a component that is located radially outward of these components in the tire radial cross section.

[0023] "Normal condition" refers to a condition in which the tire is mounted on a normal rim and filled with air at normal internal pressure, with no load applied.

[0024] "Genuine rim" refers to the rim specified for each tire in the standard system that includes the standard on which the tire is based. For example, for JATMA (Japan Automobile Tire Manufacturers Association), it refers to the standard rim for the applicable size listed in the "JATMA YEAR BOOK," for ETRTO (The European Tyre and Rim Technical Organization), it refers to the "Measuring Rim" listed in the "STANDARDS MANUAL," and for TRA (The Tire and Rim Association, Inc.), it refers to the "Design Rim" listed in the "YEAR BOOK." JATMA, ETRTO, and TRA are referenced in that order, and if an applicable size is available at the time of reference, that standard is followed. In the case of a tire not specified in the above standards, it refers to the narrowest rim among the smallest diameter rims that can be mounted on the tire and can maintain internal pressure (i.e., no air leaks from between the rim and tire).

[0025] "Normal internal pressure" refers to the air pressure specified for each tire in the standard system that includes the standard on which the tire is based. For example, for JATMA, it is "maximum air pressure," for ETRTO, it is "INFLATION PRESSURE," and for TRA, it refers to the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." As with regular rims, refer to JATMA, ETRTO, and TRA in that order, and follow that standard if there is an applicable size at the time of reference. In the case of tires not specified in the above standards, it refers to the normal internal pressure (250kPa or more) of another tire size (defined in the standard) that is specified using the regular rim as the standard rim, and if there are multiple normal internal pressures of 250kPa or more listed, it refers to the smallest value among them.

[0026] "Normal load" refers to the load specified for each tire in the standard system that includes the standard on which the tire is based. For example, for JATMA it is "Maximum Load Capacity", for ETRTO it is "Load Capacity", and for TRA it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES". As with normal rims and normal internal pressures, JATMA, ETRTO, and TRA should be referenced in that order, and if there is an applicable size at the time of reference, that standard should be followed. For tires not specified in the above standards, the maximum load capacity W calculated separately should be used. L is the normal load.

[0027] "Maximum load capacity W L " is calculated using the following formula: "V" is the virtual volume of the tire (mm 3), "Dt" is the outer diameter (mm) of the tire in its normal state, "Ht" is the tire's cross-sectional height (mm) in the tire's radial direction in a cross section of the tire taken along a plane including the tire's rotation axis, and "Wt" is the tire's cross-sectional width (mm) in its normal state. Ht can be calculated by (Dt-R) / 2, where R is the tire rim diameter. Wt is the value obtained by excluding any patterns or letters on the tire sidewall. Note that maximum load capacity is synonymous with the normal load mentioned above.

number

[0028] When the tire component is a tread, the "tread thickness" refers to the thickness of the tread measured along a normal to the tread contact surface at the tire equator in a cross section passing through the tire rotation axis. When the tire has circumferential grooves on the equator, the "tread thickness" refers to the thickness of the land portions on both sides of the groove in the tire width direction, the land portions whose center in the tire width direction is closest to the tire equatorial plane, measured along a normal to the tread contact surface at the center in the tire width direction.

[0029] When the tire component is a sidewall, the "sidewall thickness" refers to the thickness of the sidewall measured along a normal to the tire's maximum width position PW in a cross section passing through the tire's rotational axis, and is usually the distance (mm) from the sidewall surface to the carcass cord surface. The "tire's maximum width position PW" refers to the maximum width position in a cross section in the tire's width direction measured under normal conditions.

[0030] When the tire component is a clinch, the "clinch thickness" is the maximum thickness of the clinch measured along a line normal to the main body of the carcass.

[0031] When a tire component is formed from two or more rubber layers, the thickness of the tire component refers to the thickness of any one of the rubber layers that form the tire component, and is preferably the thickness of the rubber layer that is arranged axially outermost in the tire (for example, in the case of a tread portion, the thickness of the rubber layer that forms the tread surface). The thickness of the rubber layer is measured along the normal line.

[0032] The "epoxidation rate" is the ratio (mol %) of the number of epoxidized double bonds to the total number of double bonds in the rubber before epoxidation, and is measured using an NMR device (for example, JNM-ECA series manufactured by JEOL Ltd.). Note that the double bonds disappear upon epoxidation.

[0033] The "styrene content" is a value calculated by pyrolysis gas chromatography. In this specification, "pyrolysis gas chromatography" refers to a method in which a sample is heated in a pyrolysis apparatus, the individual components contained in the gas phase component generated by this heating are separated using a separation column, and each isolated component is analyzed. The styrene content is applied to rubber components having repeating units (styrene units) derived from styrene, such as SBR.

[0034] The "vinyl content (amount of 1,2-bonded butadiene units)" is a value calculated by pyrolysis gas chromatography in the same manner as the styrene content, and is applied to rubber components having repeating units derived from butadiene, such as SBR and BR.

[0035] The "cis content (amount of cis-1,4-bonded butadiene units)" is a value calculated by pyrolysis gas chromatography in the same manner as the styrene content, and is applied to rubber components having repeating units derived from butadiene, such as SBR and BR.

[0036] The "total styrene content in the rubber component" refers to the total content (mass%) of styrene units in 100% by mass of the rubber component. This is calculated by multiplying the styrene content (mass%) of each rubber component by the mass fraction in the rubber component, and then adding up the resulting values. Specifically, it is calculated as Σ(styrene content (mass%) of each styrene unit-containing rubber × content (mass%) of each styrene unit-containing rubber in the rubber component / 100). For example, if the rubber component consists of 20% by mass of a first SBR (styrene content: 25% by mass), 30% by mass of a second SBR (styrene content: 27.5% by mass), and 50% by mass of BR, the total styrene content in the rubber component is approximately 13.3% by mass (=(25 × 20 / 100) + (27.5 × 30 / 100) + (0 × 10 / 100)).

[0037] The "weight average molecular weight (Mw)" can be determined by converting the measured value into standard polystyrene equivalents using gel permeation chromatography (GPC) (for example, a GPC-8000 series manufactured by Tosoh Corporation, a differential refractometer as the detector, and a TSKgel (registered trademark) SuperMultiporeHZ-M column manufactured by Tosoh Corporation). This applies to, for example, SBR, BR, plasticizers, etc.

[0038] The "nitrogen adsorption specific surface area (N2SA) of carbon black" is measured in accordance with JIS K 6217-2:2017.

[0039] The "nitrogen adsorption specific surface area (N2SA) of silica" is measured by the BET method in accordance with ASTM D3037-93.

[0040] The "average primary particle size" is a value obtained by photographing particles with a transmission or scanning electron microscope and calculating the arithmetic mean of the particle sizes of 400 particles. If the particle shape is spherical, the particle size is the diameter of the sphere, and if the particle shape is non-spherical, the particle size is calculated from the microscope image as the circle-equivalent diameter (positive square root of {4 × (particle area) / π}).

[0041] The "softening point of the resin component" is the temperature at which the ball drops when the softening point specified in JIS K 6220-1:2015 7.7 is measured using a ring and ball softening point tester.

[0042] "Plasticizer" is a material that imparts plasticity to rubber components and is a component that is extracted from rubber compositions using acetone. Plasticizers include those that are liquid (fluid) at 25°C and those that are solid at 25°C. However, this does not include waxes and stearic acid, which are commonly used in the tire industry.

[0043] The "total plasticizer content P" includes the amount of plasticizer contained in the extended rubber component that has been previously extended with a plasticizer such as oil, resin component, or liquid rubber component. The same applies to the oil content, resin component content, and liquid rubber content. For example, if the extended component is oil, the extended oil is included in the oil content.

[0044] A procedure for producing a tire according to one embodiment of the present invention will be described in detail below. However, the following description is merely an example for explaining the present invention, and is not intended to limit the technical scope of the present invention to the scope of this description.

[0045] <Tires> Fig. 1 illustrates an example of a tire according to one embodiment of the present invention, but the present invention is not limited to this. Fig. 1 shows a portion of a cross section perpendicular to the circumferential direction of the tire. In Fig. 1, the up-down direction is the tire radial direction, the left-right direction is the tire axial direction, and the direction perpendicular to the paper surface is the tire circumferential direction.

[0046] The tire of this embodiment comprises a tread portion 1 extending circumferentially to form a ring, a pair of sidewalls 31 arranged on both sides of the tread portion, a clinch 24, a rim cushion 23, an inner liner 32, a pair of bead portions each having a bead core 21, at least one layer of carcass 33 anchored to the bead core 21, at least one layer of belt 2 arranged radially outward of the carcass 33, and a band 3 reinforcing the belt 2.

[0047] The tire according to the present embodiment is a tire including tire components made of a rubber composition described below, and is characterized in that, when the content of isoprene-based rubber in a rubber component included in the rubber composition is N (mass %) and the thickness of the tire components is t (mm), N / t is less than 2.2.

[0048] From the viewpoint of effectively exerting the effects of the present invention, the tire component in which the rubber composition is used is preferably at least one selected from the group consisting of a tread portion, a sidewall, and a clinch, and more preferably the tread portion.

[0049] From the viewpoint of the effects of the present invention, the thickness t of the tire component is preferably 2.0 mm or more, more preferably 3.0 mm or more, even more preferably 4.0 mm or more, and particularly preferably 5.0 mm or more. Also, from the viewpoint of the effects of the present invention, t is preferably 12.0 mm or less, more preferably 11.0 mm or less, even more preferably 10.0 mm or less, and particularly preferably 9.0 mm or less.

[0050] (N / t) N / t is less than 2.2, preferably less than 2.1, more preferably less than 2.0, and even more preferably less than 1.9. On the other hand, the lower limit of N / t is not particularly limited, but is preferably more than 0.5, more preferably more than 0.7, even more preferably more than 0.9, still more preferably more than 1.1, and particularly preferably more than 1.3.

[0051] [Rubber composition] The rubber composition constituting the tire member according to the present embodiment (hereinafter referred to as the rubber composition according to the present embodiment) contains a rubber component including an isoprene-based rubber and a styrene-butadiene rubber, a filler, and a plasticizer, and can be produced using the raw materials described below. The rubber composition according to the present embodiment will be described below.

[0052] <Rubber component> The rubber component according to this embodiment contains an isoprene-based rubber and a styrene-butadiene rubber (SBR) as essential components, and may further contain other rubber components.

[0053] (Diene rubber) As the rubber component, a diene rubber is preferably used. Examples of diene rubbers include isoprene rubber, butadiene rubber (BR), styrene butadiene rubber (SBR), styrene isoprene rubber (SIR), styrene isoprene butadiene rubber (SIBR), chloroprene rubber (CR), and acrylonitrile butadiene rubber (NBR). These diene rubbers may be modified rubbers treated with a modifying group capable of interacting with fillers such as carbon black or silica, or may be hydrogenated rubbers in which some of the unsaturated bonds have been hydrogenated. These diene rubbers may be used alone or in combination of two or more. Furthermore, extended rubbers that have been previously extended using a plasticizer, as described below, may also be used as the diene rubber.

[0054] The content of the diene rubber in the rubber component is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and particularly preferably 95% by mass or more. The rubber component may also consist solely of the diene rubber.

[0055] The rubber component according to the present embodiment contains isoprene-based rubber and styrene-butadiene rubber (SBR) as essential components, and may further contain butadiene rubber (BR), etc. The rubber component may also be composed only of isoprene-based rubber and SBR, or may be composed only of isoprene-based rubber, SBR, and BR.

[0056] (Isoprene rubber) The isoprene-based rubber according to the present embodiment contains an epoxidized isoprene-based rubber as an essential component, and may further contain a non-epoxidized isoprene-based rubber. The isoprene-based rubber is not particularly limited, but examples thereof include natural rubber and isoprene rubber. These isoprene-based rubbers may be used alone or in combination of two or more.

[0057] Epoxidized isoprene-based rubber may be natural rubber (epoxidized natural rubber) or isoprene rubber (epoxidized isoprene rubber). Methods for epoxidizing natural rubber include, for example, the chlorohydrin method, direct oxidation method, hydrogen peroxide method, alkyl hydroperoxide method, and peracid method (see, for example, JP-B-4-26617, JP-A-2-110182, and GB Patent No. 2113692). Examples of the peracid method include reacting natural rubber with an organic peracid such as peracetic acid or performic acid. Epoxidized natural rubber with various epoxidation rates can be prepared by adjusting the amount of organic peracid and the reaction time. The natural rubber to be epoxidized is not particularly limited, and examples include SIR20, RSS#3, TSR20, deproteinized natural rubber (DPNR), and high-purity natural rubber, which are commonly used in the tire industry.

[0058] The epoxidation rate of the epoxidized isoprene-based rubber is preferably 10 mol% or more, more preferably 15 mol% or more, and even more preferably 20 mol% or more. On the other hand, from the viewpoint of fracture properties, the epoxidation rate is preferably 75 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, and particularly preferably 40 mol% or less. The epoxidation rate is a value measured by the above-mentioned method.

[0059] The content of the epoxidized isoprene-based rubber in the rubber component is preferably more than 5% by mass, more preferably 6% by mass or more, even more preferably 8% by mass or more, and particularly preferably 10% by mass or more. On the other hand, the content of the epoxidized isoprene-based rubber in the rubber component is preferably 30% by mass or less, more preferably 27% by mass or less, even more preferably 24% by mass or less, still more preferably 21% by mass or less, even more preferably 18% by mass or less, and particularly preferably 15% by mass or less. It is believed that by setting the content of the epoxidized isoprene-based rubber within the above range, compatibility with SBR can be improved, a phase-separated structure can be formed, and stress can be more easily alleviated between the phases.

[0060] The total content N of isoprene-based rubber in the rubber component is preferably more than 5% by mass, more preferably 6% by mass or more, even more preferably 8% by mass or more, and particularly preferably 10% by mass or more. On the other hand, the total content N of isoprene-based rubber in the rubber component is preferably 30% by mass or less, more preferably 27% by mass or less, even more preferably 24% by mass or less, still more preferably 21% by mass or less, even more preferably 18% by mass or less, and particularly preferably 15% by mass or less. Note that the "total content of isoprene-based rubber" is the sum of the content of epoxidized isoprene-based rubber and the content of isoprene-based rubber other than epoxidized isoprene-based rubber.

[0061] (SBR) The SBR is not particularly limited, but examples include unmodified solution-polymerized SBR (S-SBR), emulsion-polymerized SBR (E-SBR), and modified SBRs thereof (modified S-SBR, modified E-SBR). Modified SBRs include SBRs whose ends and / or main chains are modified, and modified SBRs coupled with tin, silicon compounds, etc. (condensates, those having a branched structure, etc.). Furthermore, hydrogenated products of these SBRs (hydrogenated SBRs) can also be used. These SBRs may be used alone or in combination of two or more.

[0062] The styrene content of SBR can be appropriately selected so that the total styrene content in the rubber component falls within the range described below, but is preferably 40% by mass or less, more preferably 36% by mass or less, even more preferably 32% by mass or less, and particularly preferably 28% by mass or less. The styrene content of SBR is preferably 5% by mass or more, more preferably 7% by mass or more, even more preferably 10% by mass or more, even more preferably 13% by mass or more, and particularly preferably 16% by mass or more. The styrene content of SBR is measured by the above-mentioned measurement method.

[0063] The vinyl content of SBR is preferably more than 10 mol%, more preferably more than 15 mol%, and even more preferably more than 20 mol%. The vinyl content of SBR is preferably less than 70 mol%, more preferably less than 67 mol%, and even more preferably less than 64 mol%. In this specification, the vinyl content of SBR is measured by the above-mentioned measurement method.

[0064] From the viewpoint of the effects of the present invention, the content S of SBR in the rubber component is preferably more than 30% by mass, more preferably 40% by mass or more, even more preferably 50% by mass or more, still more preferably 60% by mass or more, and particularly preferably 70% by mass or more. On the other hand, the content S of SBR in the rubber component is preferably 99% by mass or less, more preferably 94% by mass or less, even more preferably 92% by mass or less, and particularly preferably 90% by mass or less.

[0065] (BR) The BR is not particularly limited, and examples of the BR that can be used include those commonly used in the tire industry, such as BR with a cis content of less than 50 mol% (low-cis BR), BR with a cis content of 90 mol% or more (high-cis BR), rare earth butadiene rubber (rare earth BR) synthesized using a rare earth catalyst, BR containing syndiotactic polybutadiene crystals (SPB-containing BR), and modified BR (high-cis modified BR, low-cis modified BR). These BRs may be used alone or in combination of two or more.

[0066] As the high-cis BR, for example, commercially available products from Zeon Corporation, UBE Corporation, JSR Corporation, etc. can be used. The inclusion of high-cis BR can improve low-temperature properties and wear resistance. The cis content of the high-cis BR is preferably more than 95 mol%, more preferably more than 96 mol%, and even more preferably more than 97 mol%. The cis content of BR is measured by the above-mentioned measurement method.

[0067] The rare earth BR is synthesized using a rare earth catalyst and has a vinyl content of preferably less than 1.8 mol%, more preferably less than 1.6 mol%, and even more preferably 1.5 mol% or less, and a cis content of preferably more than 95 mol%, more preferably more than 96 mol%, and even more preferably 97 mol% or more. As the rare earth BR, for example, commercially available products from LANXESS K.K. can be used.

[0068] The SPB-containing BR is not simply 1,2-syndiotactic polybutadiene crystals dispersed in the BR, but is dispersed after being chemically bonded to the BR. As such SPB-containing BR, commercially available products from UBE Corporation and the like can be used.

[0069] As the modified BR, a modified butadiene rubber (modified BR) in which the terminals and / or the main chain are modified with a functional group containing at least one element selected from the group consisting of silicon, nitrogen, and oxygen can also be suitably used.

[0070] Other examples of modified BR include tin-modified BR, which is obtained by polymerizing 1,3-butadiene with a lithium initiator and then adding a tin compound, and in which the terminals of the modified BR molecule are further bonded with a tin-carbon bond (tin-modified BR).Modified BR may be either non-hydrogenated or hydrogenated.

[0071] From the viewpoint of abrasion resistance, the weight-average molecular weight (Mw) of BR is preferably more than 200,000, more preferably more than 300,000, and even more preferably more than 400,000. From the viewpoint of crosslinking uniformity, etc., it is preferably less than 2,000,000, more preferably less than 1,000,000, and even more preferably less than 800,000. Mw can be determined by the above-mentioned method.

[0072] When BR is contained, the content in the rubber component is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and particularly preferably 7% by mass or more. On the other hand, when BR is contained, the content in the rubber component is preferably 35% by mass or less, more preferably 25% by mass or less, even more preferably 18% by mass or less, still more preferably 15% by mass or less, and particularly preferably 12% by mass or less.

[0073] (Total styrene content) From the viewpoint of the effects of the present invention, the total styrene content in the rubber component is preferably less than 30% by mass, more preferably less than 28% by mass, even more preferably less than 26% by mass, and particularly preferably less than 24% by mass. Also, from the viewpoint of the effects of the present invention, the total styrene content in the rubber component is preferably more than 5% by mass, more preferably more than 7% by mass, even more preferably more than 9% by mass, and particularly preferably more than 11% by mass.

[0074] (Other rubber components) The rubber component may contain a rubber component other than the diene rubber (non-diene rubber) to the extent that it does not affect the effects of the present invention. Examples of non-diene rubbers include rubber components commonly used in the tire industry, such as butyl rubber, ethylene propylene rubber, polynorbornene rubber, silicone rubber, chlorinated polyethylene rubber, fluororubber (FKM), acrylic rubber (ACM), and hydrin rubber. These other rubber components may be used alone or in combination of two or more. In addition to the above rubber components, a known thermoplastic elastomer may or may not be contained.

[0075] (Rubber components synthesized from recycled and biomass-derived raw materials) Monomers, which are structural units of synthetic rubbers such as IR, SBR, and BR, may be derived from underground resources such as petroleum and natural gas, or may be recycled from rubber products such as tires or non-rubber products such as polystyrene. Monomers obtained by recycling (recycled monomers) are not particularly limited, and examples include recycled polyisoprene, recycled butadiene, and recycled aromatic vinyl compounds. Examples of butadienes include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds include, but are not limited to, styrene. Among these, recycled polyisoprene (recycled isoprene), recycled butadiene (recycled butadiene), and / or recycled styrene (recycled styrene) are preferably used as raw materials.

[0076] The method for producing the recycled monomer is not particularly limited, and examples thereof include synthesis from recycled naphtha obtained by decomposing rubber products such as tires. The method for producing recycled naphtha is also not particularly limited, and examples thereof include decomposing rubber products such as tires under high temperature and pressure, decomposing with microwaves, or mechanically crushing and then extracting.

[0077] Furthermore, the monomers that are the structural units of polymers such as IR, SBR, and BR may be derived from biomass. In this specification, biomass refers to materials derived from natural resources such as plants. Examples of biomass include, but are not limited to, agricultural, forestry, and fishery products, sugar, wood chips, plant residues after useful components have been extracted, plant-derived ethanol, and biomass naphtha.

[0078] Monomers derived from biomass (biomass monomers) are not particularly limited, and examples thereof include biomass-derived butadiene and biomass-derived aromatic vinyl compounds. Examples of butadienes include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds include, but are not limited to, styrene. The method for producing biomass monomers is not particularly limited, and examples include biological and / or chemical and / or physical conversion of animals and plants. A representative example of biological conversion is fermentation by microorganisms, and examples of chemical and / or physical conversion include catalytic conversion, high heat conversion, high pressure conversion, electromagnetic wave conversion, critical fluid conversion, and combinations thereof.

[0079] Polymers synthesized from biomass monomer components (biomass polymers) are not particularly limited and include polybutadiene rubber synthesized from biomass-derived butadiene, aromatic vinyl / butadiene copolymers synthesized from biomass-derived butadiene and / or biomass-derived aromatic vinyl compounds, etc. Examples of the aromatic vinyl / butadiene copolymers include styrene-butadiene rubber synthesized from biomass-derived butadiene and / or biomass-derived styrene.

[0080] Whether a polymer's raw material is biomass-derived can be determined by its pMC (percent modern carbon) measured in accordance with ASTM D6866-10. pMC is the modern standard reference carbon. 14 of sample against C concentration 14 This is the ratio of C concentrations and is a value used as an index of the biomass ratio of a compound. The significance of this value is explained below.

[0081] 1 mole of carbon atoms (6.02 × 10 23 ) contains approximately 6.02 × 10 atoms, which is about one trillionth of the number of ordinary carbon atoms. 11 pieces 14 C exists. 14The half-life of C is 5730 years, 14 C is decreasing regularly. Therefore, in the case of fossil fuels such as coal, oil, and natural gas, which are thought to have been absorbed and fixed by plants and other organisms more than 226,000 years ago, C was also included in these when they were first fixed. 14 All C elements have decayed. Therefore, in the 21st century, fossil fuels such as coal, oil, and natural gas contain 14 Therefore, chemicals produced from these fossil fuels do not contain any C element. 14 It does not contain any C elements.

[0082] on the other hand, 14 C is constantly produced by cosmic rays undergoing nuclear reactions in the atmosphere. 14 The amount of C is balanced between radioactive decay and nuclear reaction, and in the Earth's atmospheric environment, 14 Therefore, the amount of carbon derived from biomass resources currently circulating in the environment is constant. 14 As mentioned above, the C concentration is approximately 1 × 10 -12 The value is approximately mol %. Therefore, the biomass ratio in a compound can be calculated by using the difference between these values.

[0083] this 14 C is typically measured using accelerator mass spectrometry based on a tandem accelerator. 13 C concentration ( 13 C / 12 C). 14 C concentration ( 14 C / 12 C) is measured. 14 The modern standard reference for the C concentration is the carbon circulating in nature as of 1950. 14The specific standard substance used is the oxalic acid standard provided by NIST (National Institute of Standards and Technology). The specific activity of carbon in this oxalic acid (per gram of carbon) is 14 The radioactivity of C is separated into carbon isotopes, 13 The standard value is the value corrected for decay from 1950 to the measurement date. 14 This is used as the C concentration value (100%). The ratio of this value to the value of the actually measured sample is the pMC value.

[0084] Therefore, if rubber is made from 100% biomass-derived materials, although there are regional differences, it will usually not reach 100 under normal conditions, so it will show a value of approximately 110 pMC. On the other hand, for chemical substances derived from petroleum and other fossil fuels, 14 When the carbon concentration is measured, it will show a value of about 0 pMC (for example, 0.3 pMC), which corresponds to the above-mentioned biomass ratio of 0%.

[0085] From the above, it is preferable in terms of environmental protection to use a material such as rubber having a high pMC value, that is, a material such as rubber having a high biomass ratio, in a rubber composition.

[0086] <Filler> The rubber composition according to the present embodiment contains a filler as an essential component. The filler preferably contains silica, and more preferably contains carbon black and silica. Alternatively, the filler may be composed only of carbon black and silica.

[0087] (silica) The silica is not particularly limited, and can be, for example, silica prepared by a dry method (anhydrous silica), silica prepared by a wet method (hydrated silica), or other silica commonly used in the tire industry. The raw material for silica is also not particularly limited, and can be, for example, a mineral-derived raw material such as quartz, a biological raw material such as rice husk (for example, silica made from biomass materials such as rice husk), or silica recycled from silica-containing products. Among these, hydrated silica prepared by a wet method is preferred because it contains a large number of silanol groups. These silicas can be used alone or in combination of two or more types.

[0088] As the silica according to the present embodiment, from the viewpoint of building a sustainable society, silica made from a biomass material is preferably used as a raw material. Silica made from a biomass material can be obtained, for example, by extracting silicate from rice husk ash obtained by burning rice husks using a sodium hydroxide solution, and then reacting the silicate with sulfuric acid in the same manner as conventional wet silica to produce silicon dioxide precipitates, which are then filtered, washed with water, dried, and pulverized.

[0089] Silica recycled from silica-containing products can be, for example, silica recovered from products containing silica, such as electronic components such as semiconductors, tires, desiccants, and filtering materials such as diatomaceous earth. The recovery method is not particularly limited, and examples include thermal decomposition and decomposition by electromagnetic waves. Among these, silica recovered from electronic components such as semiconductors or tires is preferred.

[0090] When silica crystallizes, it becomes insoluble in water, and its component, silicic acid, cannot be utilized. By controlling the combustion temperature and duration, the crystallization of silica in rice husk ash can be suppressed (see, for example, JP 2009-2594 A, Akita Prefectural University Web Journal B / 2019, vol. 6, pp. 216-222). Amorphous silica extracted from rice husks can be commercially available from Wilmar, Inc.

[0091] From the viewpoint of reinforcement, the nitrogen adsorption specific surface area (N2SA) of silica is 100m 2 / g or more is preferable, and 120m 2 / g is more preferable, and 150m 2 From the viewpoint of heat buildup and processability, it is more preferable that the tensile strength is more than 300 m / g. 2 / g is preferable, and 280m 2 / g is more preferable, and 250m 2 / g or less is more preferable. The N2SA of silica is measured by the above-mentioned measurement method.

[0092] The average primary particle size of silica is preferably 24 nm or less, more preferably 22 nm or less, even more preferably 20 nm or less, and particularly preferably 18 nm or less.The lower limit of the average primary particle size is not particularly limited, but from the viewpoint of the dispersibility of silica, it is preferably 1 nm or more, more preferably 3 nm or more, and even more preferably 5 nm or more.The average primary particle size of silica is measured by the above-mentioned measuring method.

[0093] From the viewpoint of the effects of the present invention, the content X of silica per 100 parts by mass of the rubber component is preferably 45 parts by mass or more, more preferably 65 parts by mass or more, even more preferably 85 parts by mass or more, still more preferably 95 parts by mass or more, and particularly preferably 105 parts by mass or more. Also, X is preferably 140 parts by mass or less, more preferably 130 parts by mass or less, and even more preferably 120 parts by mass or less.

[0094] (X / S) From the viewpoint of the effects of the present invention, X / S is preferably greater than 1.0, more preferably greater than 1.1, and even more preferably greater than 1.2. There is no particular upper limit to X / S, but it is preferably less than 4.0, more preferably less than 3.0, even more preferably less than 2.5, and particularly preferably less than 2.0.

[0095] (carbon black) Carbon black is not particularly limited, and examples thereof include N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, and N762. The raw material for carbon black may be a biomass material such as lignin or vegetable oil, or pyrolysis oil obtained by pyrolysis of waste tires. Carbon black may be produced by combustion, such as in a furnace process, by hydrothermal carbonization (HTC), or by pyrolysis of methane, such as in a thermal black process. Commercially available carbon blacks include those from Asahi Carbon Co., Ltd., Cabot Japan Co., Ltd., Tokai Carbon Co., Ltd., Mitsubishi Chemical Corporation, Lion Corporation, Nippon Steel Carbon Co., Ltd., and Columbia Carbon Co., Ltd. These carbon blacks may be used alone or in combination.

[0096] In addition to the above, from the viewpoint of life cycle assessment, carbon black may be made from a biomass material such as lignin, or recycled carbon black obtained by pyrolysis and purification of a product containing carbon black, such as a tire.

[0097] As used herein, "recycled carbon black" refers to carbon black obtained by crushing used tires or other products containing carbon black and calcining the crushed material, and refers to carbon black in which, when subjected to oxidative combustion by heating in air as measured by thermogravimetry in accordance with JIS K 6226-2:2003, the proportion of the mass of ash (ash content), which is the non-combustible component, is 13% by mass or more. In other words, the proportion of the mass (carbon content) of the recycled carbon black lost due to oxidative combustion is 87% by mass or less. Recycled carbon black is sometimes expressed as rCB.

[0098] Recycled carbon black can be obtained from the pyrolysis process of used pneumatic tires. For example, European Patent Application Publication No. 3427975, citing "Rubber Chemistry and Technology," Vol. 85, No. 3, pp. 408-449 (2012), particularly pp. 438, 440, and 442, describes the carbon black as being obtained by pyrolysis of organic materials at 550-800°C in the absence of oxygen, or by vacuum pyrolysis at relatively low temperatures (

[0027] ). Carbon black obtained from such pyrolysis processes typically lacks functional groups on its surface, as mentioned in

[0004] of Japanese Patent Publication No. 6856781 (Comparison of the Surface Morphology and Chemistry of Pyrolytic Carbon Black with Commercial Carbon Black, Powder Technology 160 (2005) pp. 190-193).

[0099] Recycled carbon black may lack functional groups on its surface, or may be treated to include functional groups on its surface. Treatment to include functional groups on the surface of recycled carbon black can be carried out by conventional methods. For example, in European Patent Application Publication No. 3,173,251, carbon black obtained from a pyrolysis process is treated with potassium permanganate under acidic conditions to obtain carbon black containing hydroxyl and / or carboxyl groups on its surface. Furthermore, in Japanese Patent Publication No. 6,856,781, carbon black obtained from a pyrolysis process is treated with an amino acid compound containing at least one thiol or disulfide group to obtain surface-activated carbon black. The recycled carbon black of this embodiment also includes carbon blacks treated to include functional groups on their surfaces.

[0100] As the recycled carbon black, commercially available products from Strable Green Carbon, LD Carbon, etc. can be used.

[0101] The nitrogen adsorption specific surface area (N2SA) of carbon black is 30m from the viewpoint of reinforcement. 2 / g or more is preferable, and 50m2 / g or more is more preferable, and 70m 2 / g or more is more preferable, and 90m 2 / g or more is particularly preferable. From the viewpoint of fuel economy and processability, 200m 2 / g or less is preferable, and 150m 2 / g or less is more preferable, and 120m 2 / g or less is more preferable.

[0102] The average primary particle size of carbon black is preferably 36 nm or less, more preferably 32 nm or less, even more preferably 28 nm or less, and particularly preferably 24 nm or less. There is no particular lower limit to the average primary particle size, but it is preferably 5 nm or more, more preferably 8 nm or more, and even more preferably 10 nm or more. The average primary particle size of carbon black is measured by the above-mentioned measurement method.

[0103] When carbon black is contained, the content per 100 parts by mass of the rubber component is preferably 1 part by mass or more, more preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more from the viewpoint of reinforcement, and is preferably less than 30 parts by mass, more preferably less than 20 parts by mass, even more preferably less than 15 parts by mass, and particularly preferably less than 10 parts by mass from the viewpoint of suppressing heat buildup.

[0104] (Other fillers) The filler may contain fillers other than silica and carbon black. The other fillers are not particularly limited, but may include, for example, fillers commonly used in the tire industry, such as aluminum hydroxide, calcium carbonate, alumina, clay, and talc.

[0105] From the viewpoint of the effects of the present invention, the total amount of the filler per 100 parts by mass of the rubber component is preferably 50 parts by mass or more, more preferably 70 parts by mass or more, even more preferably 90 parts by mass or more, and particularly preferably 100 parts by mass or more. From the viewpoint of the effects of the present invention, the total amount of the filler per 100 parts by mass of the rubber component is preferably 140 parts by mass or less, more preferably 130 parts by mass or less, and even more preferably 120 parts by mass or less.

[0106] The silica content in 100% by mass of the filler is preferably more than 50% by mass, more preferably more than 60% by mass, even more preferably more than 70% by mass, even more preferably more than 80% by mass, and particularly preferably more than 90% by mass. The silica content in 100% by mass of the filler is preferably less than 100% by mass, more preferably less than 99% by mass, and even more preferably less than 97% by mass.

[0107] When the filler consists of only carbon black and silica, once the total content of the filler and the content of either the carbon black or the silica are determined as described above, the content of the other will be determined automatically.

[0108] (Silane coupling agent) Silica is preferably used in combination with a silane coupling agent.Silane coupling agent is not particularly limited, but for example, sulfide-based silane coupling agent such as bis(3-triethoxysilylpropyl) disulfide, bis(3-triethoxysilylpropyl) tetrasulfide; mercapto-based silane coupling agent such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane; vinyl-based silane coupling agent such as vinyltriethoxysilane, vinyltrimethoxysilane; 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane Examples of suitable silane coupling agents include amino-based silane coupling agents such as γ-glycidoxypropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane; nitro-based silane coupling agents such as 3-nitropropyltrimethoxysilane and 3-nitropropyltriethoxysilane; and chloro-based silane coupling agents such as 3-chloropropyltrimethoxysilane and 3-chloropropyltriethoxysilane. Among these, sulfide-based silane coupling agents and / or mercapto-based silane coupling agents are preferred. Examples of suitable silane coupling agents include those commercially available from Evonik Industries, Momentive, and the like. These silane coupling agents may be used alone or in combination.

[0109] The content of the silane coupling agent relative to 100 parts by mass of silica is preferably 1.0 part by mass or more, more preferably 3.0 parts by mass or more, and even more preferably 5.0 parts by mass or more, from the viewpoint of improving the dispersibility of silica. From the viewpoint of cost and processability, the content 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.

[0110] <Plasticizer> The rubber composition according to the present embodiment contains a plasticizer as an essential component. A plasticizer is a material that imparts plasticity to a rubber component and encompasses both liquid and solid plasticizers at 25°C. Examples of plasticizers include resin components, oils, liquid rubbers, and ester-based plasticizers. These plasticizers may be derived from mineral resources such as petroleum and natural gas, biomass-derived plasticizers, or naphtha recycled from rubber and non-rubber products. Low-molecular-weight hydrocarbon components obtained by pyrolysis and extraction of used tires or products containing various components may also be used as plasticizers. These plasticizers may be used alone or in combination.

[0111] (resin component) The resin component is not particularly limited as long as it is a resin component commonly used in the tire industry, but examples include adhesive resins such as dicyclopentadiene resins, aromatic vinyl resins, C9 resins, C5 resins, C5C9 resins, terpene resins, rosin resins, and phenolic resins. Among these, dicyclopentadiene resins and / or aromatic vinyl resins are preferred, and dicyclopentadiene resins are more preferred. These resin components may be used alone or in combination of two or more.

[0112] <Dicyclopentadiene resin> The term "dicyclopentadiene-based resin" refers to a resin containing dicyclopentadiene (DCPD) as a monomer component, and may be a hydrogenated or modified version thereof. Examples of dicyclopentadiene-based resins include DCPD / C9 resins obtained by copolymerizing dicyclopentadiene with the C9 fraction, with DCPD / C9 resins being preferred. Examples of DCPD resins that can be used include those commercially available from ExxonMobil Corporation, ENEOS Corporation, Nippon Zeon Co., Ltd., Maruzen Petrochemical Co., Ltd., and the like. These dicyclopentadiene-based resins may be used singly or in combination of two or more.

[0113] <Aromatic vinyl resin> The term "aromatic vinyl resin" refers to a resin containing at least one aromatic vinyl compound selected from the group consisting of styrene, α-methylstyrene, vinyltoluene, p-chlorostyrene, etc., as the most abundant monomer component, preferably at least 50 mol %, and may be hydrogenated or modified. As the aromatic vinyl resin, a homopolymer of α-methylstyrene or styrene or a copolymer of α-methylstyrene and styrene is preferred, and a copolymer of α-methylstyrene and styrene is more preferred, because they are economical, easy to process, and have excellent heat generation properties. As the aromatic vinyl resin, commercially available products available from, for example, Kraton, Eastman Chemical, Mitsui Chemicals, Inc., etc., can be used. These aromatic vinyl resins may be used alone or in combination of two or more.

[0114] <C9 resin> The term "C9 resin" refers to a resin obtained by polymerizing a C9 fraction. It may be a C9 fraction polymerized 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. These resins may also be hydrogenated or modified. Examples of C9 fractions include at least one petroleum fraction having 8 to 10 carbon atoms selected from the group consisting of vinyltoluene, alkylstyrene, coumarone, indene, methylindene, and dicyclopentadiene. Specific examples of C9 resins include coumarone-indene resin, coumarone resin, and indene resin. These C9 resins may be used alone or in combination.

[0115] <C5 resin> "C5 resin" refers to a resin obtained by polymerizing a C5 fraction other than dicyclopentadiene, and may be a hydrogenated or modified version of such a resin. Examples of C5 fractions other than dicyclopentadiene include at least one petroleum fraction having 4 to 5 carbon atoms selected from the group consisting of cyclopentadiene, isoprene, pentane, isopentane, neopentane, pentene, pentadiene, etc. These C5 resins may be used alone or in combination of two or more.

[0116] <C5C9 resin> The term "C5C9 resin" refers to a resin obtained by copolymerizing the C5 fraction and the C9 fraction, and may be a hydrogenated or modified resin. As the C5C9 resin, for example, commercially available resins from Tosoh Corporation, LUHUA, etc. may be used. These C5C9 resins may be used alone or in combination of two or more.

[0117] <Terpene resin> Terpene resins refer to resins containing at least one terpene compound selected from the group consisting of α-pinene, β-pinene, limonene, dipentene, etc., as the most abundant monomer component, preferably at least 50 mol %, and may be hydrogenated or modified. Specific examples of terpene resins include polyterpene resins containing only one or more of the terpene compounds as monomer components; aromatic-modified terpene resins containing the terpene compound and an aromatic compound as monomer components; and terpene phenolic resins containing the terpene compound and a phenolic compound as monomer components. Examples of aromatic compounds that serve as monomer components for aromatic-modified terpene resins include at least one selected from the group consisting of styrene, α-methylstyrene, vinyltoluene, divinyltoluene, etc. Examples of phenolic compounds that serve as monomer components for terpene phenolic resins include at least one selected from the group consisting of phenol, bisphenol A, cresol, xylenol, etc. These terpene resins may be used alone or in combination.

[0118] <Rosin-based resin> The rosin-based resin refers to a resin containing at least one rosin acid compound selected from the group consisting of abietic acid, neoabietic acid, palustric acid, isopimaric acid, etc., and may be a hydrogenated or modified version of such a rosin-based resin. Examples of the rosin-based resin include, but are not limited to, natural rosin and rosin-modified resins obtained by modifying rosin through hydrogenation, disproportionation, dimerization, esterification, etc. These rosin-based resins may be used singly or in combination of two or more.

[0119] <Phenol-based resin> The phenolic resin refers to a resin containing a phenolic compound such as phenol or cresol as the monomer component with the largest content, preferably 50 mol% or more. Examples of the phenolic resin include, but are not limited to, phenol-formaldehyde resin, alkylphenol-formaldehyde resin, alkylphenol-acetylene resin, and oil-modified phenol-formaldehyde resin. These phenolic resins may be used alone or in combination of two or more.

[0120] From the viewpoint of the effects of the present invention, the softening point of the resin component is preferably above 50° C., more preferably above 60° C., even more preferably above 70° C., and particularly preferably above 80° C. Furthermore, from the viewpoint of improving processability and dispersibility of the rubber component and the filler, the softening point is preferably below 150° C., more preferably below 140° C., and even more preferably below 130° C. The softening point of the resin component is measured by the above-mentioned measurement method.

[0121] When a resin component is contained, the content per 100 parts by mass of the rubber component is, from the viewpoint of the effects of the present invention, preferably 5 parts by mass or more, more 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 viewpoint of suppressing heat buildup, the content is preferably 50 parts by mass or less, more preferably 45 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 35 parts by mass or less.

[0122] (oil) Examples of oils include mineral oil, vegetable oil, and animal oil. From the viewpoint of life cycle assessment, waste oils used in rubber mixers and engines, and refined waste cooking oils used in restaurants may also be used. One type of oil may be used alone, or two or more types may be used in combination.

[0123] As used herein, mineral oil refers to oil derived from mineral resources such as petroleum and natural gas. Examples of mineral oil include paraffinic oil (mineral oil), naphthenic oil, and aromatic oil. Specific examples of mineral oil include mild extracted solvate (MES), distillate aromatic extract (DAE), treated distillate aromatic extract (TDAE), treated residual aromatic extract (TRAE), and residual aromatic extract (RAE). Furthermore, as an environmental measure, oils with a low content of polycyclic aromatic compounds (PCA) can also be used. Examples of low PCA oils include MES, TDAE, and heavy naphthenic oil.

[0124] In this specification, examples of vegetable oils include linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice oil, tall oil, sesame oil, perilla oil, castor oil, tung oil, pine oil, pine tar oil, sunflower oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, and Japan wax. Further examples of vegetable oils include refined oils (such as salad oil) obtained by refining the above oils, interesterified oils obtained by interesterifying the above oils, hardened oils obtained by hydrogenating the above oils, thermally polymerized oils obtained by thermally polymerizing the above oils, oxidatively polymerized oils obtained by oxidizing the above oils, and waste edible oils recovered from edible oils. Vegetable oils may be liquid or solid at 25°C.

[0125] The vegetable oil according to this embodiment preferably contains acylglycerol, and more preferably triacylglycerol. In this specification, acylglycerol refers to a compound in which a hydroxyl group of glycerin is esterified with a fatty acid. The acylglycerol is not particularly limited 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 polymer (trimer or higher). Dimer or higher acylglycerols can be obtained by thermal polymerization, oxidative polymerization, or the like. The acylglycerol may be liquid or solid at 25°C.

[0126] The method for confirming whether the rubber composition contains the acylglycerol is not particularly limited, but may be 1 For example, a rubber composition containing triacylglycerol is immersed in deuterated chloroform at 25°C for 24 hours, and after removing the rubber composition, the 1 When H-NMR was measured, signals were observed around 5.26 ppm, 4.28 ppm, and 4.15 ppm when the signal of tetramethylsilane (TMS) was set at 0.00 ppm. These signals are presumed to be signals derived from hydrogen atoms bonded to carbon atoms adjacent to the oxygen atoms of the ester group. In this paragraph, "around" refers to a range of ±0.10 ppm.

[0127] The fatty acid is not particularly limited and may be either an unsaturated fatty acid or a saturated fatty acid. Examples of unsaturated fatty acids include monounsaturated fatty acids such as oleic acid, and polyunsaturated fatty acids such as linoleic acid and linolenic acid. Examples of saturated fatty acids include butyric acid and lauric acid.

[0128] Among these, it is desirable that the fatty acid contains a fatty acid with few double bonds, i.e., saturated fatty acid or monounsaturated fatty acid, and oleic acid is preferred. As a vegetable oil containing such a fatty acid, for example, vegetable oil containing saturated fatty acid or monounsaturated fatty acid may be used, or vegetable oil modified by ester exchange or the like may be used. Furthermore, in order to produce vegetable oil containing such a fatty acid, plants may be improved by breeding, genetic modification, genome editing, or the like.

[0129] As the vegetable oil, for example, commercially available products from Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo Co., Ltd., ENEOS Corporation, Orisoi Co., Ltd., H&R Corporation, Toyokuni Oil Mills Co., Ltd., Fuji Kosan Co., Ltd., Nisshin Oillio Group Co., Ltd., etc. can be used.

[0130] Examples of animal oils include fish oil, beef tallow, whale oil, and oleyl alcohol derived from these.

[0131] When oil is contained, the content per 100 parts by mass of the rubber component is preferably more than 20 parts by mass, more preferably more than 25 parts by mass, even more preferably more than 30 parts by mass, and particularly preferably more than 35 parts by mass, from the viewpoint of the effects of the present invention. Also, from the viewpoint of abrasion resistance, the content is preferably less than 90 parts by mass, more preferably less than 80 parts by mass, even more preferably less than 70 parts by mass, and particularly preferably less than 60 parts by mass. The oil content includes the amount of oil contained in the oil-extended rubber.

[0132] (liquid rubber) The liquid rubber is not particularly limited as long as it is a polymer that is in a liquid state at 25° C., and examples thereof 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, etc. One type of liquid rubber may be used alone, or two or more types may be used in combination.

[0133] (ester plasticizer) 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), and trixylenyl phosphate (TXP). One type of ester-based plasticizer may be used alone, or two or more types may be used in combination.

[0134] From the viewpoint of the effects of the present invention, the total content P of plasticizers per 100 parts by mass of the rubber component is preferably more than 20 parts by mass, more preferably more than 30 parts by mass, even more preferably more than 40 parts by mass, even more preferably more than 50 parts by mass, and particularly preferably more than 60 parts by mass. Also, from the viewpoint of suppressing heat buildup, P is preferably less than 100 parts by mass, more preferably less than 90 parts by mass, and even more preferably less than 80 parts by mass.

[0135] (P / N) From the viewpoint of the effects of the present invention, P / N is preferably greater than 2.0, more preferably greater than 2.5, even more preferably greater than 3.0, still more preferably greater than 3.5, and particularly preferably greater than 4.0. There is no particular upper limit to P / N, but it is preferably less than 9.0, more preferably less than 8.0, and even more preferably less than 7.5.

[0136] <Other compounding agents> In addition to the above components, the rubber composition according to the present embodiment may contain compounding agents that are generally used in the tire industry, such as vulcanized rubber particles, processing aids, waxes, antioxidants, stearic acid, zinc oxide, vulcanizing agents, and vulcanization accelerators.

[0137] (vulcanized rubber particles) The vulcanized rubber particles are particles made of vulcanized rubber, and specifically, rubber powder as specified in JIS K 6316:2017 can be used. From the standpoint of environmental considerations and cost, recycled rubber powder produced from crushed waste tires is preferred. One type of vulcanized rubber particle may be used alone, or two or more types may be used in combination.

[0138] The vulcanized rubber particles are not particularly limited, and may be unmodified vulcanized rubber particles or modified vulcanized rubber particles.

[0139] As commercially available vulcanized rubber, for example, products from Lehigh, Muraoka Rubber Industries, Ltd., etc. can be used.

[0140] (processing aids) Examples of processing aids include fatty acid metal salts, fatty acid amides, amide esters, silica surfactants, mixtures of fatty acid metal salts and amide esters, and mixtures of fatty acid metal salts and fatty acid amides. These processing aids may be used alone or in combination of two or more. Examples of processing aids that can be used include those commercially available from Schill + Seilacher, Performance Additives, etc.

[0141] When a processing aid is contained, the content thereof per 100 parts by mass of the rubber component is preferably more than 0.5 parts by mass, more preferably more than 1 part by mass, and even more preferably more than 1.5 parts by mass from the viewpoint of improving processability, and 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 from the viewpoint of abrasion resistance and breaking strength.

[0142] (wax) The wax is not particularly limited, and any wax commonly used in the tire industry can be suitably used, such as mineral waxes and plant-derived waxes. Mineral waxes refer to waxes derived from mineral resources such as oil and natural gas. Plant-derived waxes refer to waxes derived from natural resources such as plants. Among these, mineral waxes are preferred. Examples of plant-derived waxes include rice wax, carnauba wax, and candelilla wax. Examples of mineral waxes include paraffin wax, microcrystalline wax, and selected special waxes thereof, with paraffin wax being preferred. The wax according to this embodiment does not contain stearic acid. Waxes commercially available from, for example, Ouchi Shinko Chemical Industry Co., Ltd., Nippon Seiro Co., Ltd., Paramelt Co., Ltd., etc. can be used. One type of wax may be used alone, or two or more types may be used in combination.

[0143] When wax is contained, the content per 100 parts by mass of the rubber component is preferably more than 0.5 parts by mass, more preferably more than 1.0 part by mass, and even more preferably more than 1.5 parts by mass from the viewpoint of weather resistance of the rubber, and 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 from the viewpoint of preventing whitening of the tire due to bloom.

[0144] (anti-aging agent) The antioxidant is not particularly limited, but examples thereof include naphthylamine-based antioxidants such as phenyl-α-naphthylamine; diphenylamine-based antioxidants such as octylated diphenylamine and 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine; N-isopropyl-N'-phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine (6PPD), N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (77PD), N,N'-diphenyl-p-phenylenediamine (DPPD), and N,N'-ditolyl-p-phenylenediamine. p-phenylenediamine-based antioxidants such as diphenyl ether diphenyl ether (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), and N,N'-di-2-naphthyl-p-phenylenediamine (DNPD); quinoline-based antioxidants such as 2,2,4-trimethyl-1,2-dihydroquinoline polymers; monophenol-based antioxidants such as 2,6-di-t-butyl-4-methylphenol and styrenated phenol; and bis-, tris-, and polyphenol-based antioxidants such as tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane. Among these, p-phenylenediamine-based antioxidants and quinoline-based antioxidants are preferred, and polymers of N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and 2,2,4-trimethyl-1,2-dihydroquinoline are more preferred. Commercially available products that can be used include those from Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ltd., Ouchi Shinko Chemical Industry Co., Ltd., and Flexis Co., Ltd. One type of antioxidant may be used alone, or two or more types may be used in combination.

[0145] When an antioxidant is contained, the content per 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 1.4 parts by mass from the viewpoint of ozone crack resistance of the rubber, and is preferably less than 2.5 parts by mass, more preferably less than 2.0 parts by mass, and even more preferably less than 1.8 parts by mass from the viewpoint of abrasion resistance and wet grip performance.

[0146] (stearic acid) When stearic acid is contained, the content per 100 parts by mass of the rubber component is preferably more than 0.5 parts by mass, more preferably more than 1.0 part by mass, and even more preferably more than 1.5 parts by mass from the viewpoint of processability, and 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 from the viewpoint of vulcanization rate.

[0147] (zinc oxide) When zinc oxide is contained, the content per 100 parts by mass of the rubber component is preferably more than 0.5 parts by mass, more preferably more than 1.0 part by mass, and even more preferably more than 1.5 parts by mass from the viewpoint of processability, and 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 from the viewpoint of abrasion resistance.

[0148] (vulcanizing agent) Sulfur is preferably used as the vulcanizing agent. Examples of sulfur that can be used include powdered sulfur, oil-treated sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, and highly dispersible sulfur. The vulcanizing agent may be used alone or in combination of two or more.

[0149] When sulfur is contained, the content per 100 parts by mass of the rubber component is preferably more than 0.5 parts by mass, more preferably more than 0.8 parts by mass, and even more preferably more than 1.2 parts by mass, from the viewpoint of ensuring a sufficient vulcanization reaction. Furthermore, from the viewpoint of preventing deterioration, the content is preferably less than 5.0 parts by mass, more preferably less than 4.0 parts by mass, and even more preferably less than 3.0 parts by mass. When oil-containing sulfur is used as the vulcanizing agent, the content of the vulcanizing agent is the total content of pure sulfur contained in the oil-containing sulfur.

[0150] Known organic crosslinking agents can also be used as vulcanizing agents other than sulfur. The organic crosslinking agent is not particularly limited as long as it can form crosslinked chains other than polysulfide bonds. Examples of the organic crosslinking agent include alkylphenol-sulfur chloride condensate, sodium 1,6-hexamethylene-dithiosulfate dihydrate, 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane, and dicumyl peroxide. 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane is preferred. These organic crosslinking agents can be commercially available from Taoka Chemical Co., Ltd., Lanxess K.K., Flexis, and other companies.

[0151] (Vulcanization accelerator) The vulcanization accelerator is not particularly limited, but examples thereof include sulfenamide vulcanization accelerators, thiazole vulcanization accelerators, guanidine vulcanization accelerators, thiuram vulcanization accelerators, thiourea vulcanization accelerators, dithiocarbamate vulcanization accelerators, aldehyde-amine vulcanization accelerators, aldehyde-ammonia vulcanization accelerators, imidazoline vulcanization accelerators, xanthate vulcanization accelerators, and caprolactam disulfide. These vulcanization accelerators may be used alone or in combination of two or more. Among them, one or more vulcanization accelerators selected from the group consisting of sulfenamide vulcanization accelerators, thiazole vulcanization accelerators, guanidine vulcanization accelerators, and thiuram vulcanization accelerators are preferred, as they more suitably achieve the desired effects. The vulcanization accelerators may be used alone or in combination of two or more.

[0152] Examples of sulfenamide vulcanization accelerators include N-tert-butyl-2-benzothiazolylsulfenamide (TBBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), and N,N-dicyclohexyl-2-benzothiazolylsulfenamide (DCBS).

[0153] Examples of thiazole vulcanization accelerators include 2-mercaptobenzothiazole (MBT) or a salt thereof, di-2-benzothiazolyl disulfide (MBTS), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, and 2-(2,6-diethyl-4-morpholinothio)benzothiazole.

[0154] Examples of guanidine vulcanization accelerators include 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, and 1,3-di-o-cumenyl-2-propionylguanidine.

[0155] Examples of thiuram vulcanization accelerators include tetrakis(2-ethylhexyl)thiuram disulfide (TOT-N), tetramethylthiuram disulfide (TMTD), tetraethylthiuram disulfide, tetramethylthiuram monosulfide (TMTM), dipentamethylene thiuram disulfide, and dipentamethylene thiuram tetrasulfide.

[0156] When a vulcanization accelerator is contained, the content thereof per 100 parts by mass of the rubber component is preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, and even more preferably 1.5 parts by mass or more, from the viewpoint of ensuring a sufficient vulcanization rate. Moreover, the content of the vulcanization accelerator is preferably 10 parts by mass or less, more preferably 5.0 parts by mass or less, from the viewpoint of suppressing blooming.

[0157] In this specification, various materials containing carbon atoms (for example, rubber, oil, resin components, vulcanization accelerators, antioxidants, surfactants, etc.) may be derived from atmospheric carbon dioxide. As a method for obtaining such various materials from carbon dioxide, carbon dioxide may be directly converted, or methane obtained through a methanation process in which methane is synthesized from carbon dioxide may be converted.

[0158] [Production of rubber composition and tire] The rubber composition according to the present embodiment can be produced by a known method. For example, it can be produced by kneading the above-mentioned components using a rubber kneading device such as an open roll or an internal kneader (e.g., a Banbury mixer or a kneader). The kneading process may include, for example, a base kneading process in which compounding ingredients and additives other than the vulcanizing agent and vulcanization accelerator are kneaded, and a final kneading (F kneading) process in which the vulcanizing agent and vulcanization accelerator are added to the kneaded product obtained in the base kneading process and kneaded. Furthermore, the base kneading process can be divided into multiple processes as desired.

[0159] The kneading conditions are not particularly limited, but examples include a method in which the base kneading step involves kneading for 3 to 10 minutes at a discharge temperature of 150 to 170°C, and a method in which the final kneading step involves kneading for 1 to 5 minutes at 70 to 110°C. The vulcanization conditions are not particularly limited, but examples include a method in which vulcanization is carried out for 10 to 30 minutes at 150 to 200°C.

[0160] The tire according to the present embodiment, which includes tire components made from the rubber composition, can be manufactured by a conventional method. That is, an unvulcanized rubber composition obtained by blending the above-described components with a rubber component as needed is extruded to fit the shape of the corresponding tire component, and then bonded together with other tire components in a tire building machine and molded by a conventional method to form an unvulcanized tire. The unvulcanized tire is then heated and pressurized in a vulcanizer to manufacture the tire. The vulcanization conditions are not particularly limited, and examples include a method of vulcanizing at 150 to 200°C for 10 to 30 minutes.

[0161] <Application> The tire according to the present embodiment can be used for any purpose, regardless of whether it is a pneumatic tire or a non-pneumatic tire, and can be used as a passenger car tire, a large passenger car tire, a large SUV tire, a racing tire, a motorcycle tire, a heavy-duty tire, or a run-flat tire. Passenger car tires are tires designed to be mounted on four-wheeled vehicles and have a maximum load capacity of less than 1,400 kg. Heavy-duty tires are tires with a maximum load capacity of 1,400 kg or more. In this specification, the term "tire" refers to all-season tires, summer tires, and winter tires such as studless tires. [Example]

[0162] The following examples (working examples) are considered to be preferable for carrying out the present invention, but the scope of the present invention is not limited to these examples. Tires having tread portions obtained according to the formulations in Table 1 using the various chemicals shown below were examined, and the results calculated based on the evaluation methods described below are shown in Table 1.

[0163] The various chemicals used in the examples and comparative examples are listed below. SBR: Synthos SPRINTAN SLR4630 (S-SBR, styrene content: 25% by mass, vinyl content: 63 mol%, contains 37.5 parts by mass of extended oil per 100 parts by mass of rubber solids) BR: UBEPOL BR (registered trademark) 150B (unmodified BR, cis content: 97 mol%, Mw: 440,000) manufactured by UBE Corporation NR:TSR20 ENR: EPOXYPRENE 25 (epoxidized natural rubber, epoxidation rate: 25±2 mol%) manufactured by Muang Mai Guthrie Public Company Limited Carbon black: Diablack I (N220, N2SA: 114m) manufactured by Mitsubishi Chemical Corporation 2 / g, average primary particle diameter: 22nm) Silica: Wilmar K185 (amorphous silica purified from rice husks) Silane coupling agent: Si69 (bis(3-triethoxysilylpropyl)tetrasulfide) manufactured by Evonik Industries Oil: H&R VivaTec 500 (TDAE oil) Resin component 1: T-REZ PR801 (hydrogenated DCPD / C9 resin, softening point: 91°C) manufactured by ENEOS Corporation Resin component 2: Sylvatraxx (registered trademark) 4401 manufactured by Kraton (a copolymer of α-methylstyrene and styrene, softening point: 85°C) Wax: Sunnock N (paraffin wax) manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Anti-aging agent: Antigen 6C (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine) manufactured by Sumitomo Chemical Co., Ltd. Stearic acid: Camellia stearic acid beads manufactured by NOF Corporation Zinc oxide: Two types of zinc oxide manufactured by Mitsui Mining & Smelting Co., Ltd. Sulfur: Powdered sulfur manufactured by Karuizawa Sulfur Co., Ltd. Vulcanization accelerator 1: Noccela CZ (N-cyclohexyl-2-benzothiazolyl sulfenamide (CBS)) manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Vulcanization accelerator 2: Noccelaer D (1,3-diphenylguanidine (DPG)) manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Vulcanization accelerator 3: TBzTD (tetrabenzyl thiuram disulfide) manufactured by Performance Additives

[0164] Examples and Comparative Examples According to the formulation shown in Table 1, chemicals other than sulfur and vulcanization accelerators were kneaded for 1 to 10 minutes using a 1.7 L closed-type Banbury mixer until the discharge temperature reached 150 to 160°C, yielding a kneaded mixture. Next, sulfur and vulcanization accelerators were added to the kneaded mixture using a two-screw open roll mill, and the mixture was kneaded for 4 minutes until the temperature reached 105°C, yielding an unvulcanized rubber composition. The resulting unvulcanized rubber composition was molded to fit the shape of the tread portion, and bonded together with other tire components to produce an unvulcanized tire. The tire was then press-vulcanized at 150°C for 35 minutes to obtain each test tire (size: 195 / 65R15) listed in Table 1.

[0165] <Handling stability> Each test tire was mounted on each of the four wheels of a 2000cc front-wheel drive passenger vehicle, and the vehicle was driven on a test course with a dry asphalt surface. The test driver evaluated the handling characteristics based on the feeling of driving straight, changing lanes, and accelerating and decelerating while driving at 100 km / h. The evaluation was performed using an integer value of 1 to 5, with a higher score indicating better handling characteristics, and the total score of the 20 test drivers was calculated based on this evaluation standard. The total score of the control tire (Comparative Example 1) was converted to a reference value (100), and the evaluation results of each test tire were displayed as an index proportional to the total score.

[0166] <Wear resistance> Each vulcanized rubber test piece was cut from the tread of each test tire, measuring 20 mm in length, 4 mm in width, and 1 mm in thickness, with the long side aligned in the tire circumferential direction. Using an LAT (Laboratory Abrasion and Skid Tester) tester, the volume loss of each test piece was measured under conditions of a load of 100 N, a speed of 20 km / h, and a slip angle of 6°, and the abrasion resistance of each tire was expressed as an index using the following formula. The higher the index, the better the abrasion resistance. (Wear resistance performance index) = (Volume loss amount in Comparative Example 1) / (Volume loss amount of each test piece) × 100

[0167] <Overall performance> The sum of the steering stability performance and the wear resistance performance is shown as an overall performance index.

[0168] [Table 1]

[0169] <Embodiment> Examples of embodiments of the present invention are given below.

[0170] [1] A tire having tire components made of a rubber composition, the rubber composition containing a rubber component, a filler, and a plasticizer, the rubber component containing an isoprene-based rubber and a styrene-butadiene rubber, the isoprene-based rubber containing an epoxidized isoprene-based rubber, and where N (mass%) is the total content of the isoprene-based rubber in the rubber component and t (mm) is the thickness of the tire component, N / t is less than 2.2, preferably greater than 0.5 and less than 2.2. [2] The tire according to [1] above, wherein N is greater than 5, preferably 6 or greater and 30 or less. [3] The tire according to the above [1] or [2], wherein the rubber component contains more than 30% by mass, preferably 40% by mass or more, and more preferably 50% by mass or more but 94% by mass or less of styrene-butadiene rubber. [4] The tire according to any one of the above [1] to [3], wherein the total amount of styrene in the rubber component is less than 30% by mass, preferably less than 28% by mass, and more preferably more than 5% by mass and less than 26% by mass. [5] The tire according to any one of the above [1] to [4], wherein the plasticizer contains a dicyclopentadiene-based resin. [6] The tire according to any one of the above [1] to [5], wherein P / N is greater than 2.0, preferably greater than 3.0, and preferably greater than 3.5 and less than 9.0, where P (parts by mass) is the total content of plasticizers relative to 100 parts by mass of the rubber component. [7] The tire according to any one of the above [1] to [6], wherein the filler contains silica. [8] The tire according to the above item [7], wherein X / S is greater than 1.0, preferably greater than 1.1, and preferably greater than 1.2 and less than 3.0, where X (parts by mass) is the content of silica relative to 100 parts by mass of the rubber component, and S (% by mass) is the content of styrene-butadiene rubber in the rubber component. [9] The tire according to [7] or [8] above, wherein the silica is silica made from biomass materials.

[10] The tire according to any one of the above [1] to [9], wherein the tire component is at least one selected from the group consisting of a tread portion, a sidewall, and a clinch. [Explanation of symbols]

[0171] 1 Tread section 2 Belt 3 bands 21 Bead core 23 Rim cushion 24 Clinch 31 Sidewall 32 Inner liner 33 Carcass CL Tire Equator t Thickness of tire components

Claims

1. A tire having a tire component made of a rubber composition, The rubber composition contains a rubber component, a filler, and a plasticizer, the rubber component includes an isoprene-based rubber and a styrene-butadiene rubber, The isoprene-based rubber includes an epoxidized isoprene-based rubber, A tire in which N / t is less than 2.2, where N (mass%) is the total content of isoprene-based rubbers in the rubber component and t (mm) is the thickness of the tire component.

2. The tire of claim 1 wherein N is greater than 5.

3. The tire according to claim 1 or 2, wherein the rubber component contains more than 30% by mass of styrene-butadiene rubber.

4. The tire according to claim 1 or 2, wherein the total amount of styrene in the rubber component is less than 30% by mass.

5. The tire according to claim 1 or 2, wherein the plasticizer comprises a dicyclopentadiene-based resin.

6. The tire according to claim 1 or 2, wherein P / N is greater than 2.0, where P (parts by mass) is the total content of the plasticizers relative to 100 parts by mass of the rubber component.

7. The tire of claim 1 or 2, wherein the filler comprises silica.

8. 8. The tire according to claim 7, wherein X / S is greater than 1.0, where X (parts by mass) is the content of silica relative to 100 parts by mass of the rubber component and S (% by mass) is the content of the styrene-butadiene rubber in the rubber component.

9. 8. The tire of claim 7, wherein the silica is derived from a biomass material.

10. 3. The tire according to claim 1, wherein the tire component is at least one selected from the group consisting of a tread portion, a sidewall, and a clinch.

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