tire

Abstract

We provide tires that offer durability comparable to conventional tires while enabling the use of biomass polyamide fibers, thereby contributing to the global environment and resource conservation. [Solution] A tire comprising a tread, a sidewall, a clinch, a pair of bead portions each in which a bead core is embedded, an inner liner, and at least one tire member having a cord, wherein the at least one tire member having a cord has a cord containing biomass polyamide fiber.

Description

[Technical Field]

[0001] This invention relates to tires. [Background technology]

[0002] In recent years, in order to reduce environmental impact, the practical application of biomass plastics made from biomass materials has been rapidly progressing, and attempts have been made to manufacture polyamides, which are general-purpose polymer materials, from these biomass raw materials and apply them to resin products, etc. (for example, Patent Document 1). However, there are currently few examples of applying biomass-derived polyamide fibers to tire components. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Special Publication No. 2014-526584 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The present invention aims to provide a tire that enables the use of biomass polyamide fibers while ensuring durability comparable to conventional tires, thereby contributing to the global environment and resource conservation. [Means for solving the problem]

[0005] The present invention Tread and Sidewall and, A pair of bead sections, A tire comprising at least one tire member having a cord, The tire having at least one tire component containing the aforementioned cord is a tire having a cord containing biomass polyamide fibers. [Effects of the Invention]

[0006] According to the present invention, a tire is provided that enables the use of biomass polyamide fibers while ensuring durability comparable to conventional tires, thereby contributing to the global environment and resource conservation. [Brief explanation of the drawing]

[0007] [Figure 1] This is a cross-sectional view of a tire taken from a plane passing through the tire's axis of rotation. [Figure 2] This is a schematic diagram showing the tread pattern of a tire. [Figure 3] This is a schematic diagram showing the tread pattern of a tire. [Figure 4] This diagram schematically shows the belt layer as viewed from the radial direction of the tire. [Figure 5] This diagram schematically shows a cross-section of the belt layer through a plane passing through the tire's rotation axis. [Figure 6] This diagram schematically shows a cross-section of a single layer of belt ply, with a plane perpendicular to the longitudinal direction of the belt cord. [Figure 7] This is a cross-sectional view of a run-flat tire, taken from a plane passing through the tire's rotation axis. [Figure 8] This is a perspective view of a ply with a code. [Figure 9] This is a cross-section of a single cord. [Modes for carrying out the invention]

[0008] An embodiment of the present invention is a tire comprising a tread, a sidewall, a clinch, a pair of bead portions each in which a bead core is embedded, an inner liner, and at least one tire member having a cord, wherein the at least one tire member having a cord contains biomass polyamide fibers.

[0009] The polyamide constituting the biomass polyamide fiber preferably contains biomass-derived γ-butyrolactam or ε-caprolactam as a monomer component.

[0010] The polyamide constituting the biomass polyamide fiber preferably contains biomass-derived 11-aminoundecanoic acid as a monomer component.

[0011] The polyamide constituting the biomass polyamide fiber preferably contains biomass-derived pentamethylenediamine, hexamethylenediamine, or decamethylenediamine as a monomer component.

[0012] The polyamide constituting the biomass polyamide fiber preferably contains biomass-derived adipic acid, sebacic acid, or terephthalic acid as monomer components.

[0013] The tensile strength of the cord containing the biomass polyamide fibers is preferably 5.5 cN / dtex or higher.

[0014] The break elongation of the cord containing the biomass polyamide fibers is preferably 10% or more.

[0015] Preferably, the strength retention rate of the cord containing the biomass polyamide fiber after being subjected to pressure treatment at 135°C for 16 hours is 80% or more.

[0016] It is preferable that the cord containing the bioamide fibers has not been treated with a formalin-containing dipping solution.

[0017] The cord containing the bioamide fibers is preferably covered with a topping rubber.

[0018] The topping rubber preferably contains carbon black containing 1% by mass or more of zinc element.

[0019] The topping rubber preferably contains natural rubber derived from Russian dandelion and / or guayule.

[0020] The tread is composed of a rubber composition containing a rubber component, the tread includes a cap rubber layer constituting a tread ground contact surface, and the tanδ (30°C tanδTc) of the cap rubber layer at 30°C and the thickness G , , c , ,

[0026] mm of the product (30°C tanδ Tc ×G T ) is preferably 9.0 or less.

[0021] The tread is composed of a rubber composition containing a rubber component, the tread includes a cap rubber layer constituting a tread ground contact surface, and the thickness G T mm of the complex elastic modulus (30°C E* Tc ) of the cap rubber layer at 30°C (30°C E* Tc / G T ) is preferably 0.2 or less.

[0022] The land area ratio of the tread is preferably 40% or more.

[0023] The sidewall is composed of a rubber composition containing a rubber component, and the tanδ (70°C tanδ s ) of the rubber composition at 70°C is preferably 0.03 or more and 0.20 or less.

[0024] The sidewall is composed of a rubber composition containing a rubber component, and the complex elastic modulus (70°C E* s ) of the rubber composition at 70°C is preferably 2.5 MPa or more and 6.5 MPa or less.

[0025] The ratio (Hc / Ht) of the height Hc mm of the cut-in to the tire cross-section height Wt mm is preferably 0.45 or less.

[0026] The cut-in is composed of a rubber composition containing a rubber component, and the product of the tanδ (70°C tanδ c ) of the rubber component at 70°C and Hc mm (70°C tanδc × Hc) is preferably 0.6 or more and 14.0 or less.

[0027] The clinch is made of a rubber composition containing a rubber component, and the ratio of the complex modulus of elasticity of the rubber component at 70°C (70°CE*c / Hc) to Hcmm is preferably 0.07 or more and 0.75 or less.

[0028] The clinch is made of a rubber composition containing a rubber component, and when the complex modulus of elasticity of the rubber component at 70°C is 70°CcE*, the thickness of the clinch G c The product of mm and 70℃E*c (G c The temperature (70°C E*C) is preferably between 25 and 450.

[0029] The bead portion comprises a bead apex, the bead apex is made of a rubber composition containing rubber components, and the tire radial height H of the bead apex BA mm and the tanδ of the rubber composition at 70°C (70°C BA ) product (H BA ×70℃ tanδ BA ) is preferably between 0.3 and 12.0.

[0030] The bead portion comprises a bead apex, the bead apex is made of a rubber composition containing rubber components, and the tire radial height H of the bead apex BA mm and the complex modulus of elasticity of the rubber composition at 70°C (70°C E* BA ) product (H BA ×70℃E* BA ) is preferably between 100 and 9000.

[0031] The inner liner is made of a rubber composition containing rubber components, and the thickness G of the inner liner I mm and the tanδ of the rubber component at 70°C (70°C tanδ I ) product (G I ×70℃ tanδ I ) is preferably 0.02 or more and 1.40 or less.

[0032] Preferably, the at least one tire member having the aforementioned cord is a band, and the band includes at least one band ply composed of a band cord containing biomass polyamide fibers and a topping rubber covering the band cord.

[0033] Preferably, at least one tire member having the aforementioned cords is a carcass, and the carcass includes at least one carcass ply composed of a carcass cord containing biomass polyamide fibers and a topping rubber covering the carcass cord.

[0034] The carcass ply consists of a main body portion extending from the tread through the sidewall to the bead portion, and a folded portion that is folded back at the bead portion and extends toward each sidewall portion, and has a contact area where the main body portion and the folded portion are in contact, and the average cord diameter of the carcass cord is D CA , where G is the interlayer rubber gauge between the carcass cord in the main body and the carcass cord in the folded portion in the contact area, G / D CA It is preferable that the value is between 0.50 and 0.60.

[0035] Preferably, at least one tire member having the aforementioned cord is a bead reinforcement layer, and the bead reinforcement layer comprises a bead reinforcement layer cord containing biomass polyamide fibers and a topping rubber covering the bead reinforcement layer.

[0036] Furthermore, it is preferable to include a tire component having recycled steel cords.

[0037] [Definition] Figure 1 shows a cross-section of the tire including its axis of rotation, with the width direction of the tire indicated by X and the radial direction by Y. In the cross-section including the tire's axis of rotation, the center CL in the width direction is the tire's equatorial plane.

[0038] "Standard condition" refers to a state of no load where the tire is mounted on a standard rim and filled with air at the standard internal pressure. Unless otherwise specified, tires in the standard condition should be used.

[0039] A "standard rim" refers to the rim specified for each tire within the standards system that the tire is based on. 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 Organisation), 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." Refer to JATMA, ETRTO, and TRA in that order, and if an applicable size is available at the time of reference, follow that standard. In the case of a tire not specified in the above standards, it refers to the narrowest rim width among the smallest diameter rims that can be mounted on that tire and that can maintain internal pressure (i.e., do not cause air leakage between the rim and tire).

[0040] "Regular internal pressure" refers to the air pressure specified for each tire in the standards system, including the standard on which the tire is based. For example, for JATMA it refers to "maximum air pressure," for ETRTO it refers to "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 if there is an applicable size at the time of reference, follow that standard. In the case of tires not specified in the above standards, it refers to the regular internal pressure (but at least 250kPa) of another tire size (but specified in the standard) that is listed with the aforementioned regular rim as the standard rim. If multiple regular internal pressures of 250kPa or higher are listed, refer to the lowest value among them.

[0041] "Regular load (kg)" refers to the load specified for each tire in the standard system that the tire is based on. 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 regular rims and regular in-tire pressure, refer to JATMA, ETRTO, and TRA in that order, and if an applicable size is available at the time of reference, follow that standard. For tires not specified in the above standards, the maximum load capacity (kg) is calculated separately. L This is considered the normal load.

[0042] "Maximum load capacity W L The weight (kg) is calculated using the following formula: "V" is the virtual volume of the tire (mm²). 3 ), "Dt" is the outer diameter of the tire in the normal state (mm), "Ht" is the height of the tire's cross-section in the radial direction in a plane containing the tire's axis of rotation (mm), and "Wt" is the width of the tire's cross-section in the normal state (mm). Ht can be calculated by (Dt-R) / 2, where R is the rim diameter of the tire. Wt is the value obtained by removing any patterns or letters on the tire's sidewall. Note that the maximum load capacity is synonymous with the normal load mentioned above.

[0043]

number

[0044] "Tire outer diameter Dt" refers to the outer diameter of the tire in its normal state.

[0045] "Tire section width Wt" refers to the maximum width between the outer surfaces of the sidewalls in a normal state, excluding any patterns or letters on the tire sidewall.

[0046] "Tire section height Ht" refers to the height in the radial direction of the tire in the cross-section containing the tire's axis of rotation. When the tire's rim diameter is R (mm), it corresponds to half the difference between the tire's outer diameter Dt and its rim diameter R. In other words, the section height Ht can be calculated using (Dt-R) / 2.

[0047] "Tire weight" refers to the weight of the tire alone, excluding the weight of the rim. However, if the tire contains components such as sponge or sealant, or sensor components within its internal cavity, the weight includes these components.

[0048] A "groove" refers to a recessed area formed on the tread surface of a tire. A groove with an opening width of less than 2 mm on the tread surface is called a "sipe." Additionally, a groove whose inner diameter is wider than the groove width on the tread surface is called a "widened groove."

[0049] "Circumferential grooves" refer to grooves that extend continuously in the circumferential direction of the tire. Circumferential grooves may extend in a straight line along the circumferential direction, or they may extend in a wavy, sinusoidal, or zigzag pattern along the circumferential direction.

[0050] "Groove depth" refers to the maximum straight-line distance between a line connecting the ends of a groove on the tread surface and the lowest point of the groove in the tire's radial direction. If the groove depth changes in the tire's width direction or circumferential direction, this maximum value is considered the groove depth. Furthermore, the depth at points where multiple grooves intersect (three or more intersections) is excluded from the groove depth calculation.

[0051] "Groove angle" refers to the angle formed by a straight line connecting the ends of the grooves in the tread and a straight line parallel to the circumferential direction of the tire.

[0052] The "contact area" refers to the region where the tread surface makes contact with the ground when a tire, mounted on a standard rim, filled to the standard internal pressure, and subjected to a standard load. The maximum width of the contact area in the tire width direction is called the "contact width TW".

[0053] The "land area" refers to the tread region demarcated by the circumferential grooves and the contact edge of the contact area.

[0054] "Width of the land area" refers to the maximum width of the land area in the tire width direction.

[0055] "Land area ratio" refers to the ratio (%) of the area of ​​the contact area excluding the area of ​​grooves to the total area of ​​the contact area when all grooves in that contact area are filled in.

[0056] "Tread radius" refers to the radius of curvature of the arc formed by the tread surface, from the point where the tire's equatorial plane and the tread surface intersect in the meridian cross-section of the tire, outward in the tire's width direction.

[0057] "The thickness of each rubber layer constituting the tread" refers to the thickness of each rubber layer forming the tread in the radial direction of the tire on the tire's equatorial plane. If the tread is formed from multiple rubber layers, the sum of their thicknesses is "Tread Thickness G T Furthermore, if the tire has grooves on the equatorial plane, the thickness of the rubber layer in the center of the tire width direction of the land portion closest to the tire equatorial plane is the thickness of each rubber layer constituting the tread, or the tread thickness G. T Let's assume that.

[0058] "The thickness of the rubber layer constituting the sidewall" is the thickness of the rubber layer forming the sidewall in a direction parallel to the tire width direction at the position where the distance between the two sidewalls is longest on the cross-section including the tire rotation axis.

[0059] "The thickness of the rubber layer constituting the side reinforcement layer" is the maximum thickness in the tire width direction on a cross-section that includes the tire rotation axis.

[0060] "The thickness of each rubber layer constituting the clinch" refers to the thickness of the rubber layer measured along the normal to the main body of the carcass passing through point Pc, where the sidewall and the clinch contact on the outer surface of the tire. If the clinch is formed from multiple rubber layers, the sum of their thicknesses is "the clinch thickness Gc".

[0061] "Inner liner thickness," "carcass thickness," "belt layer thickness," and "band (belt reinforcement layer) thickness" are the radial thickness of each component layer on the equatorial plane of the cross-section including the tire rotation axis. If the component is not located on the equatorial plane, the radial thickness of each component layer at the center of the component in the tire width direction is used.

[0062] The "side reinforcement layer height" and the "height of the outer end of the clinch in the tire radial direction" are the straight-line distance from the lower end to the upper end of each member in the tire radial direction on a cross-section that includes the tire rotation axis.

[0063] "Bead apex height" is the straight-line distance from the lower end of the bead core to the radially outer end of the bead apex on a cross-section including the tire's rotation axis. If a bead reinforcement layer is present, it is the straight-line distance to the radially outer end of the tire including the bead reinforcement layer.

[0064] A "filament" refers to the smallest unit that forms an organic fiber cord or steel cord. A yarn is made by twisting together multiple such filaments.

[0065] The "outer diameter of the filament" is the diameter of the filament in a cross-section perpendicular to the longitudinal direction of the filament forming the organic fiber cord or steel cord. If the cross-sectional shape of the filament has a major axis and a minor axis, such as an ellipse, the simple average of these two axes shall be treated as the outer diameter of the filament.

[0066] "Yarn outer diameter" refers to the diameter of the circumscribed circle of the yarn in a cross-section perpendicular to the longitudinal direction of the yarn, when the organic fiber cord or steel cord is formed by twisting together multiple filaments.

[0067] The "outer diameter D of the cord" is the diameter of the organic fiber cord or steel cord in a cross-section perpendicular to the longitudinal direction. If the cord is made by twisting together multiple filaments or yarns, the diameter of its circumscribed circle is defined as the cord diameter. Furthermore, if the cord is not twisted and has a cross-sectional shape such as being flattened, and thus has a long axis and a short axis, the simple average of the long axis and the short axis is treated as the outer diameter of the cord.

[0068] "Number of cords arranged" refers to the number of cords per 50 mm in the arrangement direction in a cross section perpendicular to the longitudinal direction of the organic fiber cord or steel cord.

[0069] The "area occupied by the cord" is the ratio of the area occupied by the cord in a cross-section perpendicular to the longitudinal direction of the cord in a component containing the organic fiber cord or steel cord. The cross-sectional area per cord is S (mm²). 2 ), where E is the number of cords in the arrangement (cords / 50mm) and G is the thickness of the component (mm), it is defined as S × E / 50 × G × 100%.

[0070] "Fineness" refers to the weight (g) of an organic fiber cord per 1000m, and the fineness of the entire cord is called "total fineness."

[0071] "Twist count" refers to the number of twists (twists / 10cm) per 10cm along the longitudinal direction of the organic fiber cord or steel cord inside the tire. If the cord is made by gathering multiple yarns, each made by twisting multiple filaments together, and then twisting them further, the number of twists of the filaments in the yarn is called the lower twist count, and the number of twists when the yarns within the cord are twisted together is called the upper twist count.

[0072] The "twist coefficient" is calculated using the number of twists and the fineness of the cord, according to the following formula: Twist coefficient = Number of twists × Fineness 1 / 2 .

[0073] "Shaping" refers to the process of creating a wavy shape along the longitudinal direction of an organic fiber cord or steel cord.

[0074] "Heat shrinkage rate" refers to the dry heat shrinkage rate (%) of a sample cord measured in accordance with JIS L 1017:2002 "Test Method for Chemical Fiber Tire Cords," when the sample length is 500 mm and the heating conditions are 150°C for 30 minutes. This method is used for both steel cords and organic fiber cords.

[0075] "Cord strength" refers to the force (N: Newtons) measured when a tensile test is performed in accordance with JIS G 3510:1992 "Test Method for Steel Tire Cords" for steel cords. For organic fiber cords, it refers to the force (N: Newtons) measured when a tensile test is performed in accordance with JIS L 1017:2002 "Test Method for Chemical Fiber Tire Cords" at a temperature of 20°C.

[0076] The "elastic modulus of the cord" is the elastic modulus (cN / dtex) of a single cord wire calculated from the slope (ss curve) when the cord wire is stretched by 1.5%, in accordance with JIS L 1017:2002 "Test Method for Chemical Fiber Tire Cords". This measurement method is used for both steel cords and organic fiber cords.

[0077] The "cord pull-out force" is the maximum load (N) until the cord is pulled out, measured under conditions of room temperature (23°C) and a speed of 50 mm / min, in accordance with ASTM-1871 "Standard Test Method for Adhesion Between Tire Bead Wire and Rubber".

[0078] The "breaking strength of organic fiber cords" and "breaking elongation of organic fiber cords" are measured in accordance with the standard time test of JIS L 1013:2010.

[0079] The "strength retention rate of organic fiber cords" is determined by the following formula, using the tensile strength of fiber A and fiber B, which is extracted from the tubular knitted fabric after the organic fiber A is knitted in a tube and subjected to pressure treatment at 135°C for 16 hours. Strength retention rate (%) = (Breaking strength of fiber B / Breaking strength of fiber A) × 100

[0080] "Biomass" refers to materials of biological origin, excluding organic materials that have been converted by geological processes into elements selected from a group consisting of petroleum, petrochemicals, and combinations thereof.

[0081] "Biomass content" refers to the proportion of biomass-derived components in the organic fiber cord, and is determined in accordance with ISO 16620-3 "Method for determining biomass plastic content".

[0082] "Styrene content of rubber components (mass%)" is calculated by multiplying the styrene content of each rubber component that makes up the entire rubber component (100 mass%) by its percentage of the total rubber component, and then summing up all of these values.

[0083] "Vinyl content of rubber components (mol%)" is calculated by multiplying the vinylbutadiene unit content derived from the 1,2-butadiene bond of each rubber component that makes up the total rubber components (100% by mass) by its content in the total rubber components, and then summing up all of these values.

[0084] The "glass transition temperature of a rubber composition" is defined as the temperature at which the loss tangent (tanδ) of the rubber composition reaches its maximum value in the temperature dispersion curve of the loss tangent (tanδ) in the range of -60°C to 40°C after vulcanization. If tanδ continuously increases with increasing temperature in the range of -60°C to 40°C, then, according to the above definition, the glass transition temperature of the rubber composition is 40°C. Conversely, if tanδ continuously decreases with increasing temperature in the range of -60°C to 40°C, then the glass transition temperature of the rubber composition is similarly -60°C. Furthermore, if there are two or more points in the range of -60°C to 40°C where tanδ is maximum, the lowest temperature among these points is treated as the glass transition temperature of the rubber composition.

[0085] "Rubber components of a rubber composition" refer to components that contribute to crosslinking within a rubber composition, and generally have a weight-average molecular weight (Mw) of 10,000 or more.

[0086] A "softener" is a material that imparts plasticity to rubber components and is extracted from rubber compositions using acetone. Softeners include those that are liquid at 25°C and those that are solid at 25°C. However, waxes and stearic acid commonly used in the tire industry are excluded.

[0087] "Softener content" includes the amount of softener contained in the stretchable rubber component that has been pre-stretched with softeners such as oil, resin components, and liquid rubber components. The same applies to the oil content, resin component content, and liquid rubber content; for example, if the stretchable component is oil, the stretchable oil is included in the oil content.

[0088] "Sulfur content of rubber composition" refers to the total amount of sulfur contained in the rubber composition, derived from crosslinking agents, vulcanization accelerators, carbon black, etc.

[0089] The "glass transition temperature of the rubber component" is the average value obtained by multiplying the glass transition temperature of each rubber component forming the rubber composition by the mass percentage contained in the rubber component. Here, the glass transition temperature of each rubber component is different from the glass transition temperature of the rubber composition, and is the static glass transition temperature of each rubber component determined by differential operating calorimeter (DSC).

[0090] [Measurement method] The "contact area" is obtained by mounting the tire onto a standard rim, filling it with the standard internal pressure, applying ink to the tire tread surface, applying the standard load, and pressing it vertically onto cardboard to transfer the image. After performing the same transfer process at a total of five locations by rotating the tire 72 degrees each time, the "contact width TW" can be calculated by finding the average of the maximum widths of the shapes of each contact area.

[0091] "Width of the land area" refers to the maximum width in the tire width direction of each land area in the shape of the five contact areas obtained in the measurement of the contact area, and the average value of the maximum width of the same land area obtained from the five measurements is used.

[0092] The "land area ratio" can be calculated by determining the ratio (%) of the area of ​​the five contact shapes to the average of the total area of ​​the five contact areas obtained by smoothly connecting the outer ring angles that are interrupted by grooves in the shape of the five contact areas obtained in the measurement of the contact area. That is, it can be calculated as the average value of the area of ​​the five contact shapes ÷ the average value of the total area of ​​the five locations × 100.

[0093] The "groove width" can be determined from the length between the groove edges that appear on the tread surface of the tire in a meridional cross-section.

[0094] The "thickness of each rubber layer constituting the tread," "thickness of the rubber layer constituting the sidewall," "thickness of the rubber layer constituting the side reinforcement layer," "thickness of each rubber layer constituting the clinch," "thickness of the inner liner," "thickness of the carcass layer," "thickness of the belt layer," "thickness of the belt reinforcement layer," "height of the side reinforcement layer," "height of the clinch," and "height of the bead apex" are measured using the average value of each measurement taken at five cross-sections including the tire rotation axis, with the tire rotated 72 degrees at each point. These measurements can be taken by creating a cross-sectional section including the tire rotation axis and measuring the distance between the beads with the bead aligned to the standard rim width.

[0095] The "outer diameter of the filament," "outer diameter of the yarn," "outer diameter of the cord," "cross-sectional area of ​​the cord," and "number of cords in the arrangement" can be calculated from the average value of each value obtained within a range of ±25 mm from the point where the cord intersects the equatorial plane in a cross-sectional section cut along the longitudinal direction of the cord. If the arrangement direction of the cord is perpendicular to the circumferential direction of the tire, these values ​​can be obtained by calculating the values ​​of each cord within a 50 mm range in any range of the cord cut on the equatorial plane.

[0096] The "fineness" can be determined by calculating the weight of a 1000m length of the cord after removing the protective rubber layer attached to the cord extracted from the tire. If it is not possible to extract a 1000m length of cord from the tire, the fineness can be determined by extracting a length of 10cm or more and calculating the weight per 1000m.

[0097] The "loss tangent and complex modulus of elasticity of the rubber composition" are the loss tangent (tanδ) and complex modulus E* (MPa) measured in extension mode under various conditions using a dynamic viscoelasticity measuring device (e.g., GABO's Iplexer series). The sample used for dynamic viscoelasticity measurement is a vulcanized rubber composition measuring 20 mm in length, 4 mm in width, and 1 mm in thickness. When creating a sample by cutting it from a tire, if the component used to create the sample is the tread, belt reinforcement layer, belt layer, or inner liner, the length direction should be aligned with the tire's circumferential direction, and the thickness direction should be aligned with the tire's radial direction. If the component used to create the sample is the sidewall, clinch, bead apex, or side reinforcement layer, the length direction of the sample should be aligned with the tangential direction to the tire's circumferential direction, and the thickness direction should be aligned with the tire's width direction. In all cases, the sample should be prepared to be as close as possible to the specified dimensions. The strain applied to the sample is normalized with respect to length, and both the measured tanδ and E* are normalized with respect to the width and thickness of the sample, so it is considered that there is no influence from the size of the sample. Tanδ at 0°C is measured under the conditions of 0°C, 10Hz frequency, 10% initial strain, and ±2.5% dynamic strain. E* at 0°C is measured under the conditions of 0°C, 10Hz frequency, 10% initial strain, and ±2.5% dynamic strain. Tanδ and E* at 30°C are measured under the conditions of 30°C, 10Hz frequency, 5% initial strain, and ±1% dynamic strain. Tanδ and E* at 70°C are measured under the conditions of 70°C, 10Hz frequency, 5% initial strain, and ±1% dynamic strain.

[0098] The glass transition temperature of a rubber composition is measured in the same way as the loss tangent and complex modulus of the rubber composition. It is measured using a dynamic viscoelasticity analyzer (e.g., GABO's Iplexer series) in extension mode on a sample prepared for the rubber composition. The measurement is performed under conditions of a frequency of 10 Hz, initial strain of 10%, dynamic strain of ±0.5%, and heating rate of 2°C / min. The temperature distribution curve of tanδ is measured in the range of -60°C to 40°C, and the temperature is determined as the temperature corresponding to the largest tanδ value in the obtained temperature distribution curve.

[0099] The Shore hardness of rubber compositions is measured by pressing a Type A durometer against the sample at 23°C, in accordance with JIS K 6253. When preparing a hardness measurement sample from a test tire, if the sample is the tread, the tread is cut from the surface side forming the contact surface of the test tire so that the tire radius direction is the thickness direction, and the Type A durometer is pressed against the sample from the surface side for measurement. If the sample is a component other than the tread, the tire is cut at a cross-section including the axis of rotation, the cross-section is smoothed, and then the Type A durometer is pressed against the component from the cross-sectional direction for measurement.

[0100] The "100% modulus of the rubber composition," "breaking strength of the rubber composition," and "elongation at break of the rubber composition" are measured using a 1mm thick, No. 7 dumbbell-shaped test specimen. Tensile tests are conducted in accordance with JIS K 6251 "Vulcanized rubber and thermoplastic rubber - Determination of tensile test properties" at a 23°C atmosphere and a tensile speed of 3.3 mm / sec. The measured values ​​are the 100% tensile stress (MPa), breaking strength (MPa), and elongation at break (%). When preparing the measurement sample from a test tire, the longitudinal and thickness directions are the same as those for measuring tanδ and E* of the rubber composition. If it is difficult to take a sample with a thickness of 1mm, the sample should be taken as close to 1mm as possible. This is because the 100% modulus, breaking strength, and elongation at break are all measured using standardized values, and therefore are not affected by thickness.

[0101] The "glass transition temperature of the rubber component" is measured in accordance with JIS K 7121 by using a differential scanning calorimeter (for example, a differential scanning calorimeter (Q200) manufactured by T.A. Instruments Japan Co., Ltd.) while increasing the temperature at a heating rate of 10°C / min.

[0102] "Styrene content" is, 1 This value is calculated by 1H-NMR measurement and is applied, for example, to rubber components (styrene unit-containing rubber) that have repeating units derived from styrene, such as SBR.

[0103] "Vinyl content (amount of 1,2-bonded butadiene units)" is a value calculated by infrared absorption spectroscopy in accordance with JIS K 6239-2:2017, and is applied to rubber components having repeating units derived from butadiene, such as SBR and BR.

[0104] "Cis content (amount of cis-1,4-bonded butadiene units)" is a value calculated by infrared absorption spectroscopy in accordance with JIS K 6239-2:2017, and is applied, for example, to rubber components having repeating units derived from butadiene, such as BR.

[0105] The "weight-average molecular weight (Mw)" can be determined by converting it to standard polystyrene based on measurements obtained by gel permeation chromatography (GPC) (for example, the GPC-8000 series manufactured by Tosoh Corporation, with a differential refractometer as the detector and TSKgel® SuperMultiporeHZ-M column manufactured by Tosoh Corporation). This method is applied, for example, to SBR, BR, and plasticizers.

[0106] The nitrogen adsorption specific surface area (N2SA) of carbon black is measured in accordance with JIS K 6217-2:2017. The nitrogen adsorption specific surface area (N2SA) of silica is measured by the BET method in accordance with ASTM D3037-93.

[0107] The "average primary particle diameter" is a value obtained by photographing particles with a transmission or scanning electron microscope and taking the arithmetic mean of the particle diameters of 400 particles. If the particle is spherical, the diameter of the sphere is used as the particle diameter; if it is not spherical, the equivalent diameter of a circle (the positive square root of {4 × (particle area) / π}) is calculated from the microscope image and used as the particle diameter.

[0108] The "softening point of the resin component" is the temperature at which the sphere drops when the softening point specified in JIS K 6220-1:2001 is measured using a ring-type softening point measuring device.

[0109] [tire] A tire according to one embodiment of the present invention will be described below with reference to the drawings. Note that the embodiments shown below are merely examples, and the tire of the present invention is not limited to the embodiments described below.

[0110] Figure 1 is a diagram illustrating a cross-section of a tire including its axis of rotation. In Figure 1, the Y direction is the radial direction of tire 1, and the X direction is the width direction of tire 1. The tread 2 comprises a cap rubber layer 2a that constitutes the tread contact surface and a base rubber layer 2b located on the innermost part of the tread in the radial direction of the tire.

[0111] Although Figure 1 shows an example of a two-layer tread 2 consisting of a cap rubber layer 2a and a base rubber layer 2b, the tread 2 may also consist of a single-layer tread or a tread with a structure of three or more layers. Furthermore, the tread 2 may have multiple different rubber layers in the width direction of the tire. In Figure 1, the cap rubber layer 2a is divided by circumferential grooves, resulting in multiple rubber layers in the width direction of the tire.

[0112] Furthermore, if the amount of carbon black contained in the rubber composition of the cap rubber layer of the tread 2 is small and it is difficult to ensure electrical conductivity, an electrically conductive rubber member 2c may be provided in the tread 2.

[0113] Tread thickness G T The thickness is preferably 4.0 mm or more, more preferably 4.5 mm or more, and even more preferably 5.0 mm or more. On the other hand, there is no particular upper limit, but it is preferably 18.0 mm or less, more preferably 17.0 mm or less, and even more preferably 16.0 mm or less.

[0114] When the tread 2 is formed from multiple rubber layers in the radial direction of the tire, the thickness G of the cap rubber layer of the tread 2 TC The thickness is preferably 1.0 mm or more, and more preferably 2.0 mm or more. On the other hand, there is no particular upper limit, but it is preferably 16.0 mm or less, and more preferably 14.0 mm or less.

[0115] Furthermore, if the tread 2 is formed from multiple rubber layers, the thickness G of the base rubber layer of the tread 2. TB The thickness is preferably 0.5 mm or more, more preferably 0.7 mm or more, and even more preferably 1.0 mm or more. On the other hand, there is no particular upper limit, but it is preferably 8.0 mm or less, more preferably 7.5 mm or less, and even more preferably 7.0 mm or less.

[0116] Furthermore, if the tread 2 is formed from multiple rubber layers, the thickness G of the tread 2 T Thickness G of the cap rubber layer forming tread 2 Tc The ratio (G Tc / G T The ratio is preferably 0.10 or higher, and more preferably 0.15 or higher. On the other hand, there is no particular upper limit, but it is preferably 0.95 or lower, and more preferably 0.90 or lower.

[0117] Furthermore, if the tread 2 is formed from multiple rubber layers, the thickness G of the tread 2 T Thickness G of the base rubber layer of the rubber layer forming the tread 2 TB The ratio (G TB / G T The ratio is preferably 0.70 or less, and more preferably 0.50 or less. On the other hand, there is no particular limit to the lower limit, but it is preferably 0.05 or more, and more preferably 0.10 or more.

[0118] Tread 2 cap rubber layer at 0°C: tanδ(0°C tanδ) TC ) is preferably 0.1 or higher, and preferably 1.0 or lower.

[0119] Tread 2 cap rubber layer at 30°C: tanδ(30°C tanδ) TC The value of ) is preferably 0.01 or higher, and preferably 0.60 or lower.

[0120] E*(30℃E*) of the cap rubber layer of Tread 2 TCThe pressure (MPa) is preferably 1 MPa or higher, and preferably 100 MPa or lower.

[0121] Tread 2 cap rubber layer glass transition temperature (Tg TC The temperature (°C) is preferably -60°C or higher, and preferably 0°C or lower.

[0122] Tread 2 cap rubber layer hardness HS TC It is preferably 30 or more, and preferably 95 or less.

[0123] Modulus M100 when the tread 2 cap rubber layer is 100% stretched. TC The pressure (MPa) is preferably 1 MPa or higher, and preferably 100 MPa or lower.

[0124] Breaking strength of the cap rubber layer of Tread 2 TB TC The pressure (MPa) is preferably 1 MPa or higher, and preferably 100 MPa or lower.

[0125] Elongation at break of the rubber cap layer of Tread 2 EB TC (%) is preferably 100% or more, and preferably 100% or less.

[0126] Tread 2 base rubber layer at 70°C tanδ (70°C tanδ TB The value is preferably 0.25 or less, more preferably 0.20 or less, and more preferably 0.15 or less. There is no particular lower limit, but it is preferably 0.01 or more, more preferably 0.02 or more, and even more preferably 0.03 or more.

[0127] E* of the base rubber layer of tread 2 at 70°C (70°C E* TB The pressure is preferably 1.5 MPa or higher, more preferably 2.0 MPa or higher, and even more preferably 3.0 MPa or higher. On the other hand, there is no particular upper limit, but it is preferably 25.0 MPa or lower, more preferably 20 MPa or lower, and even more preferably 15 MPa or lower.

[0128] Tread 2 base rubber layer glass transition temperature TgTB The temperature is preferably 0°C or below, preferably -15°C or below, and more preferably -20°C or below. There is no particular lower limit, but -60°C or above is preferred.

[0129] Tread 2 base rubber layer hardness HS TB It is preferable that the value be 40 or higher, and preferably 75 or lower.

[0130] Modulus M100 at 100% stretch of the base rubber layer of Tread 2 TB The pressure is preferably 1.5 MPa or higher, and preferably 10.0 MPa or lower.

[0131] Tread 2 Base Rubber Layer Breaking Strength TB TB The pressure is preferably 10 MPa or higher, and preferably 40 MPa or lower.

[0132] Elongation at break of the base rubber layer EB of Tread 2 TB It is preferably 150% or more, and preferably 500% or less.

[0133] When the tread 2 is formed from three or more rubber layers, the values ​​of the intermediate rubber layers other than the cap rubber layer and base rubber layer are not particularly limited and can be set to any range depending on the application.

[0134] Furthermore, the various physical properties of the rubber composition, such as tanδ, E*, rubber hardness Hs, modulus, TB, and EB, can be appropriately adjusted by the type and amount of rubber components, fillers, softeners, etc., as described below. For example, 30℃E* can be increased by increasing the amount of fillers in the rubber composition or decreasing the amount of softener, and rubber hardness Hs can be increased by increasing the amount of fillers in the rubber composition or decreasing the amount of softener.

[0135] The tread may have circumferential grooves extending in the circumferential direction. In tire 1, the tread has two circumferential grooves 12 extending in the circumferential direction. The circumferential grooves 12 may extend in a straight line along the circumferential direction, curve along the circumferential direction, or extend in a zigzag pattern along the circumferential direction. The circumferential grooves 12 do not necessarily have to be continuously connected in the circumferential direction; for example, they may be separated by lateral grooves.

[0136] Groove depth D at the deepest part of the circumferential groove 12 S The thickness is preferably 3.0 mm or more, more preferably 3.5 mm or more, and even more preferably 4.0 mm or more. On the other hand, there is no particular upper limit, but it is preferably 15.0 mm or less, preferably 14.0 mm or less, and even more preferably 12.0 mm or less.

[0137] Tread thickness G T and the groove depth D of the deepest part of the circumferential groove 12 S The difference (G T -D S The diameter is preferably 5.0 mm or less, preferably 3.0 mm or less, and more preferably 2.0 mm or less. On the other hand, there is no particular limit to the lower limit, but it is preferably 0.2 mm or more, more preferably 0.3 mm or more, and even more preferably 0.5 mm or more.

[0138] Tread thickness G T and the 30°C tanδ of the tread 2 cap rubber layer TC The product of (30℃ tanδ TC ×G T ) is preferably 9.0 mm or less.

[0139] Tread thickness G T 30℃E* of the cap rubber layer of tread 2 TC Ratio (30℃E* TC / G T The pressure is preferably 0.2 MPa / mm or higher.

[0140] If the tread 2 is formed of three or more rubber layers, the thickness G of the cap rubber layer of the tread 2. TC The depth D of the deepest part of the circumferential groove 12 is S It is preferable that it be smaller than this.

[0141] The maximum opening width W in the tire width direction on the tread surface of the circumferential groove 12 S It is preferably 2.0 mm or more, and more preferably 15.0 mm or less.

[0142] Furthermore, the circumferential groove 12 has the opening width W S Alternatively, a widened groove that is wider on the inner side in the radial direction of the tire may also be used.

[0143] Figure 2 shows a schematic diagram of an example of a tread pattern. As shown in Figure 2, the tread pattern has three circumferential grooves 12 that extend continuously in the circumferential direction of the tire, and transverse grooves 13, 18 and sipes 14, 15 that extend in the width direction.

[0144] In Figure 2, three circumferential grooves 12 are provided, but the number of circumferential grooves is not particularly limited and may be, for example, two to five. Also, although the circumferential grooves 12 extend in a straight line along the circumferential direction, they are not limited to this configuration and may extend in a wavy, sinusoidal, or zigzag pattern along the circumferential direction.

[0145] The tread pattern in Figure 2 has three circumferential grooves 12 and land sections 16 and 17 separated by the tread contact edge Te. The pair of land sections 17 separated by the outermost circumferential groove 12 in the tire width direction and the tread contact edge Te are called shoulder land sections, and the land section 16 located inside the shoulder land sections in the tire width direction is called the center land section. In Figure 2, there are a total of four land sections: two shoulder land sections and two center land sections, but the number of land sections is not particularly limited and may be, for example, one to six.

[0146] The land portion may be provided with transverse grooves (widthwise grooves) and / or sipes. In Figure 2, the shoulder land portion 17, separated by two tread contact ends Te and circumferential grooves 12, is provided with a plurality of shoulder transverse grooves 13 whose ends open to the circumferential grooves 12 and the contact ends Te, and a plurality of shoulder sipes 14 whose one end opens to the circumferential grooves 12. In addition to this configuration, the tread may also be provided with transverse grooves whose one end opens to the circumferential grooves 12 and whose other end terminates within the land portion 17, or with sipes whose one end opens to the circumferential grooves 12 and whose other end opens to the contact end Te.

[0147] When the shoulder lateral groove 13 is present on the shoulder land portion 17, it is preferable that the spacing between the shoulder lateral groove 13 in the circumferential direction of the tire be 3.0 mm or more. On the other hand, the spacing between the shoulder lateral groove 13 is not particularly limited, but it is preferable that it be 80.0 mm or less.

[0148] If the shoulder land portion 17 has a shoulder transverse groove 13, the groove depth D of the shoulder transverse groove 13 SH The thickness is preferably 2.0 mm or more, and more preferably 3.0 mm or more. On the other hand, the upper limit is preferably 17.0 mm or less, and more preferably 15.0 mm or less.

[0149] When the shoulder land portion 17 has a shoulder lateral groove 13, the groove angle C is the angle that the longitudinal direction of the shoulder lateral groove 17 makes with the tire width direction on the tread surface. S The temperature is preferably in the range of 75 to 115 degrees.

[0150] One shoulder, land portion, width 17W LS It is preferable that the contact width TW is 40% or less. Also, in a pair of shoulder land sections 17, the widths of each shoulder land section may be the same or different.

[0151] When the shoulder sipes 13 are present on the shoulder land portion 17, it is preferable that the spacing between the shoulder sipes 17 in the circumferential direction of the tire be 1.0 mm or more. On the other hand, there is no particular upper limit to the spacing between the shoulder sipes 17, but it is preferable that it be 60.0 mm or less.

[0152] When the shoulder land portion 17 has shoulder sipes 14, the depth of the shoulder sipes 14 is preferably 2.0 mm or more. On the other hand, there is no particular upper limit, but it is preferably 10.0 mm or less, and more preferably 8.0 mm or less.

[0153] Furthermore, the central land area 16, which is separated only by the circumferential grooves 12, is provided with a plurality of center sipes 15, one end of which opens into the circumferential grooves 12, and transverse grooves 18, both ends of which open into the circumferential grooves 16. However, the configuration is not limited to this, and the land area 16 may also have sipes that open into the circumferential grooves 12 at both ends, and transverse grooves that open into only one side of the circumferential groove.

[0154] The land area ratio of the tread pattern is preferably 40% or more, more preferably 45% or more, and even more preferably 55% or more. On the other hand, there is no particular upper limit, and it may be 100%.

[0155] The land sections 16 and 17 may have one or more small holes. In Figure 2, a small hole 19 is provided in the center land section 16, which is separated by circumferential grooves. The opening area of ​​the small hole on the tread surface is 0.1 to 15 mm². 2 It is preferable.

[0156] In one land area 16 or land area 17, the circumferential length L of the tire T Total number of small holes 19 per (mm) N(N / L) T The value of ) is preferably 0.05 to 2.0, preferably 0.1 to 1.0, and more preferably 0.2 to 0.8.

[0157] The depth of the deepest part of the small hole 19 is preferably 30 to 90% of the depth of the circumferential groove 12.

[0158] Furthermore, in another embodiment of the present invention, as shown in Figure 3, the tread 2 may consist of grooves extending in the circumferential direction of the tire, comprising inclined lateral grooves and inclined connecting grooves that connect adjacent inclined lateral grooves.

[0159] In Figure 3, the tread 2 comprises a first tread pattern portion P1 positioned on one side in the tire width direction relative to the tire equator CL, and a second tread pattern portion P2 positioned on the other side in the tire axial direction. These first and second tread pattern portions P1 and P2 have a line-symmetric pattern that is offset from each other in the tire circumferential direction (i.e., phase-shifted in the tire circumferential direction).

[0160] The first and second tread pattern sections P1 and P2 each comprise a plurality of inclined lateral grooves 20 spaced apart in the circumferential direction of the tire, and at least one inclined connecting groove 21 connecting adjacent inclined lateral grooves 20, 20 in the circumferential direction of the tire. In this example, one inclined connecting groove 21 is provided approximately in the center of each of the tread pattern sections P1 and P2. Furthermore, the invention is not limited to this embodiment, and for example, it may be composed of an inner inclined connecting groove provided on the inside in the tire width direction and an outer inclined connecting groove provided on the outside in the tire width direction.

[0161] Furthermore, the tread is provided with sipes 22 that intersect with the inclined joint grooves 21 of the first and second tread pattern sections P1 and P2.

[0162] In tire 1 shown in Figure 1, each sidewall 3 extends radially inward from the edge of the tread 2. The radially outer portion of this sidewall 3 is joined to the tread 2 and the wing 4. The radially outer end of the sidewall 3 may terminate on the radially inner side of the tread 2 as shown in Figure 1, or it may terminate radially outside the cap rubber layer of the tread 2 so as to overlap the tread 2.

[0163] The radially inner portion of the sidewall 3 is joined to the clinch 5. The radially inner end of the sidewall 3 may be exposed to the tire surface, or it may not be exposed to the tire surface in such a way that it is tucked inside the clinch 5 in the tire width direction.

[0164] The sidewall 3 may be formed from two or more rubber layers, each having a layer that is not partially or completely exposed on the tire surface. Furthermore, the partially exposed layer may be a rubber layer colored other than black for aesthetic reasons.

[0165] Furthermore, the sidewall 3 may have periodic irregularities for aesthetic reasons. These irregularities can include decorations such as letters and patterns, as well as serrations to make irregularities caused by the joints of internal components less visible, or minute protrusions that are finer than serrations and designed to increase optical blackness.

[0166] Furthermore, electronic tags or other devices that enable communication with the outside may be embedded inside the sidewall 3.

[0167] Sidewall 3 thickness G S The thickness is preferably 7.0 mm or less, more preferably 6.0 mm or less, and even more preferably 5.0 mm or less. On the other hand, the lower limit is not particularly limited, but is preferably 0.1 mm or more, preferably 0.5 mm or more, and even more preferably 0.8 mm or more.

[0168] Sidewall 3 at 70°C tanδ(70°C tanδ) S The value is preferably 0.30 or less, preferably 0.25 or less, and more preferably 0.20 or less. There is no particular lower limit, but it is preferably 0.01 or more, more preferably 0.02 or more, and even more preferably 0.03 or more.

[0169] E* at 70°C for sidewall 3 (70°C E* S) is preferably 1.5 MPa or more, more preferably 2.0 MPa or more, and even more preferably 2.5 MPa or more. On the other hand, the upper limit is not particularly limited, but preferably 10.0 MPa or less, more preferably 8.0 MPa or less, and even more preferably 6.5 MPa or less.

[0170] The glass transition temperature Tg of the rubber composition of the sidewall 3 S is preferably 0 °C or less, preferably -15 °C or less, and even more preferably -20 °C or less. The lower limit is not particularly limited, but preferably -60 °C or more.

[0171] The hardness HS of the sidewall 3 S is preferably 40 or more and preferably 60 or less.

[0172] The modulus at 100% elongation M100 of the sidewall 3 S (MPa) is preferably 0.5 MPa or more and preferably 5.0 MPa or less.

[0173] The breaking strength TB of the sidewall 3 S is preferably 10 MPa or more and preferably 40 MPa or less.

[0174] The elongation at break EB of the sidewall 3 S is preferably 150% or more and preferably 500% or less.

[0175] The wing 4 in FIG. 1 is located between the tread 2 and the sidewall 3. The wing 4 is joined to each of the tread 2 and the sidewall 3. Note that the wing 4 may or may not be provided.

[0176] The clinch 5 in Figure 1 is located approximately radially inward of the sidewall 3 and has at least one portion that contacts the rim. Furthermore, a chafer 11 may be provided in a portion of the part that contacts the rim, from the viewpoint of the durability of the clinch 5. The chafer 11 may be a canvas chafer having organic fibers inside, or a rubber chafer formed from a rubber composition.

[0177] The outer end of the clinch 5 in the tire radial direction may or may not be exposed to the tire surface. The height Hc of the clinch 5 is preferably 75 mm or less, and more preferably 70 mm or less. On the other hand, there is no particular lower limit, but it is preferably 10 mm or more, and more preferably 15 mm or more.

[0178] Furthermore, the ratio of the height of the clinch 5 Hc (mm) to the tire section height Ht (mm) (Hc / Ht) is preferably 0.5 or less, and more preferably 0.45 or less. There is no particular lower limit, but 0.1 or more is preferred.

[0179] The maximum thickness Gc of the clinch 5 is preferably 30 mm or less, and more preferably 20 mm or less. On the other hand, the lower limit is not particularly limited, but is preferably 2 mm or more, and more preferably 4 mm or more.

[0180] The tanδ (70°C tanδc) of the rubber composition constituting the clinch at 70°C is preferably 0.25 or less, and more preferably 0.15 or less. On the other hand, there is no particular lower limit, but it is preferably 0.02 or more, and more preferably 0.03 or more.

[0181] The E* (70°C E*c) of the rubber composition constituting Clinch 5 at 70°C is preferably 4 MPa or higher, and more preferably 5 MPa or higher. On the other hand, there is no particular upper limit, but it is preferably 20 MPa or lower, and more preferably 15 MPa or lower.

[0182] The product of the height Hc of clinch 5 and 70°C tanδc (70°C tanδc × Hc) is preferably 14.0 mm or less, and more preferably 12.0 mm or less. On the other hand, there is no particular lower limit, but it is preferably 0.4 mm or more, and more preferably 0.6 mm or more.

[0183] The ratio of 70°C E*c to the height Hc of clinch 5 (70°C E*c / Hc) is preferably 0.05 MPa / mm or higher, and more preferably 0.07 MPa / mm or higher. On the other hand, there is no particular upper limit, but it is preferably 1.00 MPa / mm or lower, and more preferably 0.75 MPa / mm or lower.

[0184] The product of the clinch 5 thickness Gc and 70°C tanδc (Gc × 70°C tanδc) is preferably 7.50 mm or less, and more preferably 6.00 mm or less. On the other hand, there is no particular lower limit, but it is preferably 0.10 mm or more, and more preferably 0.25 mm or more.

[0185] The product of the clinch 5 thickness Gc and 70°C E*c (Gc × 70°C E*c) is preferably 20 MPa·mm or more, and more preferably 25 MPa·mm or more. On the other hand, there is no particular upper limit, but it is preferably 600 MPa·mm or less, and more preferably 450 MPa·mm or less.

[0186] The glass transition temperature (Tgc) of the rubber composition constituting Clinch 5 is preferably 0°C or lower, preferably -15°C or lower, and more preferably -20°C or lower. There is no particular lower limit, but -60°C or higher is preferred.

[0187] The hardness HSc of the rubber composition constituting Clinch 5 is preferably 50 or higher, and preferably 90 or lower.

[0188] Modulus M100 of the rubber composition constituting Clinch 5 at 100% elongation S The pressure is preferably 2.0 MPa or higher, and preferably 15.0 MPa or lower.

[0189] The tensile strength TBc of the rubber composition constituting Clinch 5 is preferably 10 MPa or higher, and preferably 40 MPa or lower.

[0190] The tensile strength TBc of the rubber composition constituting Clinch 5 is preferably 10 MPa or higher, and preferably 40 MPa or lower.

[0191] The bead portion 6 in Figure 1 comprises a bead core 6a, a bead apex 6b, and a bead reinforcing layer 6c.

[0192] Each bead core 6a is preferably ring-shaped and contains a wound, non-stretchable wire. The bead core 6a may be manufactured by winding a tape of multiple bead wires together, or a cable-shaped bead core may be used in which multiple wires are spirally wound around a single core wire.

[0193] When the bead core 6a is manufactured by winding a tape with multiple bead wires aligned, the number of bead wires in the tape arranged in the radial direction of the tire may differ in each layer. In this case, the type of tape to be wound can be changed each time the tape is wound in the circumferential direction of the tire.

[0194] On the other hand, if the bead core 6a is a cable-shaped bead core obtained by spirally winding multiple wires around a single core wire, the core cord may consist of one wire or multiple wires. Also, the number of wires surrounding the core cord can be 3 to 10.

[0195] The bead core 6a has a bead apex 6b that extends radially outward from the bead core 6a. The bead apex 6b tapers radially outward.

[0196] Bead apex diameter height H BAis preferably 5 mm or more, more preferably 7 mm or more. On the other hand, although the upper limit is not particularly limited, it is preferably 60 mm or less, more preferably 55 mm or less. In the case of including the bead reinforcing layer 6c, the height H of the bead apex BA is the higher value of the height of either the bead apex 6b or the bead reinforcing layer 6c.

[0197] The tanδ (70°C tanδ) at 70°C of the rubber composition constituting the bead apex 6b BA ) is preferably 0.25 or less, more preferably 0.22 or less. On the other hand, although the lower limit is not particularly limited, it is preferably 0.02 or more, more preferably 0.03 or more. In the case of including the bead reinforcing layer 6c, the 70°C tanδ of the bead apex 6b BA is the lower value of the 70°C tanδ of the rubber composition constituting either the bead apex 6b or the bead reinforcing layer 6c.

[0198] Further, the complex elastic modulus (70°C E*) at 70°C of the rubber composition constituting the bead apex 6b BA ) is preferably 8 MPa or more, more preferably 10 MPa or more. On the other hand, although the upper limit is not particularly limited, it is preferably 200 MPa or less, more preferably 150 MPa or less. In the case of including the bead reinforcing layer 6c, the 70°C E* of the rubber composition constituting the bead apex 6b BA is the higher value of the 70°C E*δ of either the bead apex 6b or the bead reinforcing layer 6c.

[0199] The height H in the tire radial direction of the bead apex 6b BA and 70°C tanδ BA The product of (H BA × 70°C tanδ BA ) is preferably 15.0 mm or less, more preferably 12.0 mm or less. On the other hand, although the lower limit is not particularly limited, it is preferably 0.2 mm or more, more preferably 0.3 mm or more.

[0200] The height H in the tire radial direction of the bead apex 6b BAand 70℃E* BA The product of (H BA ×70℃E* BA The pressure is preferably 80 MPa·mm or higher, and more preferably 100 MPa·mm or higher. On the other hand, there is no particular lower limit, but it is preferably 12000 MPa·mm or lower, and more preferably 9000 MPa·mm or lower.

[0201] Hardness HS of the rubber composition constituting Bead Apex 6b BA It is preferable that the hardness is 70 or higher, and preferably 100 or lower. Furthermore, if a bead reinforcement layer 6c is provided, the hardness of the bead apex 6b is HS. BA This value represents the higher of either the hardness of bead apex 6b or bead reinforcement layer 6c.

[0202] Modulus M100 of the rubber composition constituting bead apex 6b at 100% elongation BA The pressure is preferably 5.0 MPa or higher, and preferably 30 MPa or lower. Furthermore, if a bead reinforcement layer 6c is provided, the modulus M100 of the bead apex 6b at 100% elongation is... BA This is the higher of either the modulus of bead apex 6b or bead reinforcement layer 6c at 100% elongation.

[0203] Breaking strength TB of the rubber composition constituting Bead Apex 6b BA The strength is preferably 10 MPa or higher, and preferably 40 MPa or lower. Furthermore, if a bead reinforcement layer 6c is provided, the breaking strength TB of the bead apex 6b should be... BA This value represents the higher of either the fracture strength of bead apex 6b or bead reinforcement layer 6c.

[0204] Elongation at break EB of the rubber composition constituting bead apex 6b BA It is preferable that it be 70% or more, and preferably 250% or less. Furthermore, if a bead reinforcement layer 6c is provided, the elongation at break EB of the bead apex 6b BAThis is the higher of the two values: the elongation at break of bead apex 6b or bead reinforcement layer 6c.

[0205] In Figure 1, the bead portion 6 is provided with a bead reinforcement layer 6c on the outer side in the tire width direction of the carcass layer 8. In Figure 1, the bead reinforcement layer consists of one ply, but it may consist of two or more ply. The bead reinforcement layer 6c may also extend around the bead core 6a in a substantially U-shape in cross-section along the carcass ply 8a. Furthermore, the bead reinforcement layer 6c may be located between the main body portion and the folded portion of the carcass ply 8a in the axial direction.

[0206] Although not shown in the diagram, the bead reinforcement layer 6c preferably consists of a number of parallel cords (bead reinforcement layer cords) and a covering rubber layer.

[0207] The inner liner 7 is formed to form the inner surface of the tire cavity, and this component reduces air permeability and helps maintain tire internal pressure. An insulation layer may be provided between the inner liner 7 and the carcass layer 8 from the viewpoint of adhesion.

[0208] Inner liner 7 thickness G I The thickness is preferably 0.2 mm or more, and more preferably 0.3 mm or more. On the other hand, there is no particular upper limit, but it is preferably 5.0 mm or less, and more preferably 4.0 mm or less.

[0209] The tanδ(70°C tanδ) of the rubber composition constituting the inner liner 7 at 70°C I The value of ) is preferably 0.30 or less, and more preferably 0.28 or less. On the other hand, the lower limit is not particularly limited, but is preferably 0.05 or more, and more preferably 0.08 or more.

[0210] Furthermore, the complex modulus of elasticity (70°CE*) of the rubber composition constituting the inner liner 7 at 70°C is also present. I The pressure is preferably 2.0 MPa or higher, and more preferably 2.5 MPa or higher. On the other hand, there is no particular upper limit, but it is preferably 8.0 MPa or lower, and more preferably 7.0 MPa or lower.

[0211] Inner liner 7, thickness G I and 70℃ tanδ I The product of (G I ×70℃ tanδ I The diameter is preferably 1.50 mm or less, and more preferably 1.40 mm or less. On the other hand, there is no particular lower limit, but it is preferably 0.01 mm or more, and more preferably 0.02 mm or more.

[0212] Inner liner 7, thickness G I The product of 70℃E* (G I ×70℃E* I The pressure is preferably 40.0 MPa·mm or less, and more preferably 35.0 MPa·mm or less. On the other hand, there is no particular lower limit, but it is preferably 0.4 MPa·mm or more, and more preferably 0.5 MPa·mm or more.

[0213] Hardness HS of the rubber composition constituting the inner liner 7 I It is preferable that the value is 35 or higher, and preferably 55 or lower.

[0214] Modulus M100 of the rubber composition constituting the inner liner 7 at 100% elongation I The pressure is preferably 0.2 MPa or higher, and preferably 5.0 MPa or lower.

[0215] Breaking strength TB of the rubber composition constituting the inner liner 7 I The pressure is preferably 7 MPa or higher, and preferably 25 MPa or lower.

[0216] Elongation at break EB of the rubber composition constituting the inner liner 7 I It is preferable that it be 400% or more, and preferably 1000% or less.

[0217] A sealant layer may be attached to the inner liner 7 on the inner surface side of the tire cavity to seal holes in the event of a puncture. In addition, one or more low-density members selected from the group consisting of sound dampening materials and three-dimensional mesh structures may be attached to the inner liner layer 7 on the inner surface side of the tire cavity. By providing low-density members, when vibrations are transmitted from the tread surface, these low-density members vibrate inside the tire, thereby canceling out vibrations within the tread.

[0218] As the sealant layer, those generally used on the inner circumference of the tire tread for puncture prevention can be suitably used. A specific example of such a sealant layer is, for example, the one described in Japanese Patent Publication No. 2020-23152. The thickness of the sealant layer is usually preferably 1 to 10 mm. The width of the sealant layer is usually preferably 85 to 115% of the maximum width of the belt layer, and preferably 95 to 105%.

[0219] Any sound-dampening material that can exert a sound-dampening effect within the tire cavity can be suitably used. Specific examples of such sound-dampening materials include, for example, those described in Japanese Patent Publication No. 2019-142503. The sound-dampening material is, for example, composed of a porous sponge material. The sponge material is a sponge-like porous structure, and includes, for example, a so-called sponge itself with open cells made by foaming rubber or synthetic resin, as well as a web-like structure in which animal fibers, plant fibers, or synthetic fibers are intertwined and linked together. Furthermore, "porous structure" includes not only those with open cells but also those with closed cells. An example of a sound-dampening material is an open-cell sponge material made of polyurethane. Suitable sponge materials include synthetic resin sponges such as ether-based polyurethane sponges, ester-based polyurethane sponges, and polyethylene sponges, as well as rubber sponges such as chloroprene rubber sponges (CR sponges), ethylene propylene rubber sponges (EDPM sponges), and nitrile rubber sponges (NBR sponges). In particular, polyurethane-based or polyethylene-based sponges, including ether-based polyurethane sponges, are preferred from the viewpoint of sound dampening, lightness, adjustability of foaming, and durability.

[0220] Generally, any material that acts as a sound-absorbing material can be suitably used as the three-dimensional mesh structure. A specific example of such a sound-absorbing material is, for example, the one described in Japanese Patent Publication No. 2018-90131. More specifically, the three-dimensional mesh structure is formed by the irregular entanglement of multiple molten resin strands, with the entangled portions being welded together.

[0221] The three-dimensional mesh structure is preferably fixed to the inner surface of the tire. The method of fixing it to the inner surface of the tire is not particularly limited; for example, it may be bonded to the inner surface of the tire with an adhesive, but it may also be fixed by the sealant material that constitutes the sealant layer, and such fixing is preferred.

[0222] The thickness of the three-dimensional mesh structure is not particularly limited, but is preferably 1.0 to 150 mm, more preferably 30 to 120 mm. The width is not particularly limited, but is preferably 50 to 95% of the width of the above-mentioned sealant layer, and more preferably 60 to 90% for the reason that the effect can be more preferably obtained.

[0223] A sensing core or the like for monitoring the state of the tire in real time may be attached to the inner surface side of the inner liner 7 of the tire.

[0224] The carcass 8 includes a carcass ply 8a. In the tire 1 of FIG. 1, the carcass 8 is composed of one carcass ply 8a, but may be composed of two or more.

[0225] In the tire 1 of FIG. 1, the carcass ply 8a is spanned between the bead cores 6a on both sides and is along the tread 2 and the sidewall 3. The carcass ply 8a is folded back from the inner side to the outer side in the axial direction around the bead core 6a. That is, the carcass ply 8a includes a main body portion and a folded-back portion at the bead core.

[0226] In addition, when a plurality of carcass plies 8a are provided, all the carcass plies 8a may have a folded-back portion, and if any one has a folded-back portion, the others may not have a folded-back portion.

[0227] When the carcass ply 8a of the tire 1 has a folded-back portion, the folded-back portion may or may not be adjacent to its main body portion. Also, the height H of the outer end portion of the folded-back portion in the tire radial direction K is lower than the height H of the end portion of the belt layer BE . Also, H K may be higher or lower than the height of the end portion of the clinch. Also, H K may be higher or lower than the tire radial height H of the bead apex BA .

[0228] Although not shown in the diagram, the carcass ply 8a preferably consists of a number of parallel cords (carcass cords) and a covering rubber layer. The absolute value of the angle that each cord makes with respect to the equatorial plane CL is preferably between 75° and 90°. In other words, it is preferable that this carcass 8 has a radial structure.

[0229] Furthermore, the angles that the numerous cords arranged in the main body and folded portion of the carcass ply make with respect to the equatorial plane CL may be the same or different.

[0230] As the carcass cord, either an organic fiber cord or a steel cord, as described later, can be used.

[0231] Outer diameter d of the carcass cord K The thickness is preferably 0.5 mm or more, and preferably 1.5 mm or less.

[0232] Number of carcass cords E K Preferably, the number of strands per 50 mm is 40 or more, and preferably 60 or less.

[0233] Outer diameter d of the carcass cord K and number of rows E K The product of (D K ×E K ) is preferably 20 or more, and preferably 90 or less.

[0234] The area occupied by the carcass cord is preferably 50% or more, and preferably 95% or less.

[0235] The heat shrinkage rate of the carcass cord is preferably 0.01% or more, and preferably 5.0% or less.

[0236] The tanδ(70°C tanδ) of the rubber composition constituting the coating rubber layer of the carcass cord at 70°C K The value is preferably 0.30 or less. The lower limit is not particularly limited, but it is preferably 0.05 or more.

[0237] The tanδ(70°C tanδ) of the rubber composition constituting the coating rubber layer of the carcass cord at 70°C K The value is preferably 0.30 or less. The lower limit is not particularly limited, but it is preferably 0.05 or more.

[0238] The belt layer 9 in Figure 1 is located radially inward of the tread 2. The belt layer 9 is laminated on top of the carcass 8. The belt layer 9 reinforces the carcass 8. In the tire 1 of Figure 1, the belt layer 9 consists of two belt plies: an inner belt ply 9a and an outer belt ply 9b. As is clear from Figure 1, in the tire width direction, it is desirable that the width W9a of the inner belt ply 9a in the tire width direction is greater than the width W9b of the outer belt ply 9b. In this tire 1, the axial width of the belt layer 9 is preferably 0.6 times or more, and preferably 0.9 times or less, the cross-sectional width of the tire 1.

[0239] Although Figure 1 shows an example of a belt layer 9 consisting of two layers of belt plies, an inner belt ply 9a and an outer belt ply 9b, the belt layer 9 may also consist of a single layer of belt plies or three or more layers of belt plies.

[0240] The inner belt ply 9a and outer belt ply 9b in Figure 1 are constructed by arranging multiple belt cords in parallel and covering them with belt topping rubber.

[0241] Here, Figure 4 is a schematic diagram of the belt layer viewed from the tire radial direction, Figure 5 is a schematic diagram of the cross-section of the belt layer with respect to a plane passing through the tire rotation axis, and Figure 6 is a schematic diagram of the cross-section of one belt ply layer with respect to a plane perpendicular to the longitudinal direction of the belt cord. Note that in Figure 4, the band layer 10a (full band) adjacent to the belt layer 9 is shown, but the band layer 10b (edge ​​band) is omitted from the illustration. Also, the diagonal lines applied to the belt plies 9a, 9b and the band layer 10a represent the arrangement direction of the contained cords.

[0242] From FIG. 4, the belt cords in the inner belt ply 9a and the belt cords in the outer belt ply 9b are inclined at angles of θ9a and θ9b with respect to the tire circumferential direction, respectively. θ9a and θ9b are not particularly limited, but are preferably within the range of ±15 to 60 degrees. Further, when there are a plurality of belt plies as shown in FIG. 4, it is preferable that the angles θ formed by the belt cords in adjacent belt plies with the tire circumferential direction are opposite in sign. By doing so, a hoop effect can be generated, and it becomes possible to easily restrain the carcass 8.

[0243] In FIG. 5, G BB is the distance on the tire equatorial plane of the line segment connecting the centers of the belt cord cross-sections included in each layer, for the belt cords included in two adjacent layers of belt plies 9a and 9b. G BB is preferably 0.1 mm or more and preferably 1.0 mm or less.

[0244] Further, since the belt cords are arranged inclined at an angle θ with respect to the tire circumferential direction, even when the cross-sectional shape perpendicular to the longitudinal direction of the belt cord is a perfect circle, in the cross-section in the tire width direction, the cross-sectional shape of the belt cord becomes an ellipse or the like.

[0245] In FIG. 6, the cross-sectional shape of the belt cord is a perfect circle, but it is not limited to such a mode, and the cross-sectional shape of the belt cord may be an ellipse or a track shape.

[0246] The outer diameter d of the belt cord B is preferably 0.2 mm or more and more preferably 0.5 mm or more.

[0247] When the cross-sectional shape of the belt cord is a shape having a major axis and a minor axis, such as an ellipse, the ratio of the major axis to the minor axis (major axis / minor axis) is preferably 1.05 or more and more preferably 1.10 or more. On the other hand, the upper limit is not particularly limited, but is preferably 2.00 or less and more preferably 1.80 or less.

[0248] For durability and other reasons, belt cords that have been pre-curled in the longitudinal direction may be used.

[0249] Furthermore, the number of belt cords arranged in a cross section perpendicular to the longitudinal direction of the belt cord E B The ratio is preferably 60 strands / 50 mm or less, and more preferably 55 strands / 50 mm or less. On the other hand, the lower limit is preferably 30 strands / 50 mm or more, and more preferably 35 strands / 50 mm or more.

[0250] Furthermore, in a cross-section perpendicular to the longitudinal direction of the belt cord, the distance d between adjacent belt cords is also considered. BB The thickness is preferably 0.01 mm or more, and preferably 0.5 mm or less.

[0251] Furthermore, the thickness of the belt ply G B The thickness is preferably 0.25 mm or more, and preferably 2.5 mm or less.

[0252] The area occupied by the belt cord is preferably 50% or more, and preferably 95% or less.

[0253] belt cord outer diameter d B and number of rows E B The product of (d B ×E B ) is preferably 6 or more, and preferably 30 or less.

[0254] The belt cord is preferably covered with belt topping rubber. The tanδ(70°C tanδ) of the rubber composition constituting the belt topping rubber is specified. BE ) is preferably 0.20 or less. On the other hand, the lower limit is not particularly limited, but is preferably 0.04 or more.

[0255] Modulus M100 of the rubber composition constituting the belt topping rubber at 100% elongation. BE The pressure is preferably 1 MPa or higher, and preferably 100 MPa or lower.

[0256] Breaking strength TB of the rubber composition constituting the belt topping rubberBE The pressure is preferably 10 MPa or higher, and preferably 40 MPa or lower.

[0257] Elongation at break EB of the rubber composition constituting the belt topping rubber BE It is preferably 150% or more, and preferably 500% or less.

[0258] Furthermore, from the viewpoint of improving the adhesion between the belt cord and the belt topping rubber, it is preferable that the belt topping rubber contains salts of metal elements whose ionization tendency falls between that of copper and zinc, such as cobalt, nickel, bismuth, antimony, and iron. Additionally, from the viewpoint of further improving adhesion, adhesive resins such as polybenzoxazine compounds and phenolic resins may be included.

[0259] Furthermore, from the viewpoint of improving the adhesion between the belt cord and the belt topping rubber, it is preferable that a plating layer containing copper and zinc is formed on the surface of the belt cord. Moreover, it is even more preferable that the plating includes, in addition to the aforementioned copper and zinc, metal elements such as cobalt, nickel, bismuth, and antimony, whose ionization tendencies fall between those of copper and zinc.

[0260] In Figure 1, the band (belt reinforcement layer) 10 is located radially outside the belt layer 9. In the tire 1 of Figure 1, the band 10 has a width equal to the width of the belt ply 9a in the tire width direction, but it may have a width greater than the width of the belt ply 9a.

[0261] In Figure 1, the band 10 is formed from a radially inner band ply 10a that covers the entire belt and an edge band ply 10b that covers only the edge portion of the belt layer. However, the band is not limited to this configuration. For example, the band may include a layer that is continuous in the tire width direction, or it may cover only the radially outer portion of both ends of the belt layer in the tire width direction. Also, in Figure 1, the band is formed from two layers, but the band is not limited to this configuration. It may be formed from one layer, or from three or more layers.

[0262] Although not shown in the figure, band 10 preferably consists of a band cord and band topping rubber. The band cord is wound spirally in the circumferential direction of the tire. Such a band has a so-called jointless structure. The band cord extends substantially in the circumferential direction of the tire. The angle of the band cord with respect to the circumferential direction of the tire is preferably ±10° or less, and more preferably ±5° or less. Since the belt layer 9 is restrained by this band cord, the increase in the outer diameter of the tire due to internal pressure during driving is suppressed.

[0263] Band 10 can be made of either an organic fiber cord or a steel cord, as described later.

[0264] Band cord outer diameter d BAND The thickness is preferably 0.5 mm or more, and preferably 1.5 mm or less.

[0265] Number of band chords in the arrangement E BAND Preferably, the number of strands per 50 mm is 30 or more, and preferably 90 or less.

[0266] The area occupied by the band code is preferably 50% or more, and preferably 95% or less.

[0267] The heat shrinkage rate of the band cord is preferably 0.01% or more, and preferably 5.0% or less.

[0268] Outer diameter d of the band cordBAND and number of rows E BAND The product of (d BAND ×E BAND ) is preferably 15 or more, and preferably 130 or less.

[0269] The tanδ(70°C tanδ) of the rubber composition constituting the rubber covering of the band cord at 70°C BAND The value is preferably 0.30 or less. The lower limit is not particularly limited, but it is preferably 0.05 or more.

[0270] E*(70°CE*) of the rubber composition constituting the rubber covering of the band cord BAND The pressure is preferably 3.0 MPa or higher, and preferably 10.0 MPa or lower.

[0271] Another embodiment of a tire is the run-flat tire. A run-flat tire is a tire designed to support a vehicle even when air pressure is lost, and it usually has a side reinforcement layer for this purpose. Here, the side reinforcement layer refers to the rubber layer located on the inside of the sidewall of the run-flat tire.

[0272] Figure 7 shows the right half of a cross-sectional view of a run-flat tire. Figure 7 is a schematic diagram with unnecessary components such as wings and bands omitted. In Figure 7, the side reinforcement layer 23 is arranged in contact with the inside of the carcass, extending from the bead portion to the shoulder portion of the tread. The side reinforcement layer 30 is arranged between the main body portion of the carcass and its folded portion, extending from the bead portion 7 to the tread portion 5, or arranged in two layers between multiple carcass plies or reinforcement plies. The side reinforcement layer 23 is arranged in a roughly crescent shape, with its cross-sectional shape gradually decreasing in thickness towards both ends in the vertical direction, but is not limited to this shape.

[0273] [code] The tire of the present invention comprises at least one tire member having a cord, wherein the at least one tire member having the cord has a cord containing biomass polyester fiber and / or recycled polyester fiber.

[0274] Figure 8 shows a perspective view of a ply 30 included in the tire 1 of the present invention. As shown in Figure 8, the tire of the present invention includes a ply 30 in which a plurality of cords 31 are covered with topping rubber 32. The ply 30 is applied to at least one of the carcass ply 8a, band ply 10a, and bead reinforcement layer 6c described above.

[0275] Figure 9 shows a cross-sectional view of a single cord 31. As shown in Figure 9, each cord 31 is made up of multiple filaments 14 with an outer diameter d twisted together. In a preferred embodiment, the cord 31 of this embodiment is made up of multiple (two in Figure 9) under-twisted yarns 33, each made up of multiple filaments 34 twisted together. Furthermore, in the cord 31 of the present invention, since two under-twisted yarns 33 are twisted together, a portion 33a of the outer surface of the under-twisted yarn 33 (corresponding to the contact surface of the two under-twisted yarns 13) is flattened. As a result, the cross-sectional shape of the cord 31 is approximately oval, with the cross-sectional width decreasing in the central part. However, the cord of the present invention is not limited to this embodiment.

[0276] The average cord diameter D is obtained by the simple average of the major axis D1 and minor axis D2 in the cross-section of the cord 31. The major axis D1 represents the maximum diameter of the cord 11. The minor axis D2 represents the maximum diameter of the cord 31 in the direction perpendicular to the major axis D1. In this embodiment, the cord 11 extends in the length direction of the cord 31 with a constant cross-sectional shape, but the cross-sectional shape and cross-sectional area of ​​the cord 31 may change in the length direction of the cord 31. In this case, it is preferable to measure the average cord diameter D at the position where the cross-sectional area of ​​the cord 31 is minimum. This is because the effective tensile strength of the cord depends on the configuration of the cord at the position where the cross-sectional area of ​​the cord is minimum.

[0277] The code 31 contained in ply 30 is a code containing biomass polyamide fibers. That is, the filament 34 of code 31 contains biomass polyamide fibers.

[0278] Biomass polyamide fibers can be obtained, for example, by spinning biomass polyamide obtained by the method described below using a known method.

[0279] Biomass polyamides are polyamides obtained from raw materials containing monomers derived from biomass. Therefore, biomass polyamides contain monomer units derived from biomass.

[0280] In the production of biomass polyamides, monomers derived from fossil fuels may be used in addition to monomers derived from biomass. That is, biomass polyamides may contain monomer units derived from fossil fuels in addition to monomer units derived from biomass.

[0281] Biomass-derived monomers may be produced directly from biomass-derived raw materials by extraction or fermentation, or by chemically converting products obtained by extraction or fermentation. Alternatively, commercially available biomass-derived monomers may be used.

[0282] The following describes the raw material monomers that can be used to derive the constituent units contained in polyamides, followed by a description of specific polyamides. Examples of raw material monomers include lactams, aminocarboxylic acids, diamines, and dicarboxylic acids.

[0283] Polyamides can be obtained by known methods, such as ring-opening polymerization of lactams, polycondensation of aminocarboxylic acids, polycondensation of diamines and dicarboxylic acids, and combinations thereof.

[0284] The lactam is not particularly limited, but lactams having 4 to 12 carbon atoms are preferred. Specifically, examples include γ-butyrolactam (2-pyrrolidone), δ-valerolactam, ε-caprolactam, enantractam, undecanelactam, and dodecanelactam. Among these, γ-butyrolactam and ε-caprolactam are preferred.

[0285] Biomass-derived lactams can be produced by known methods. For example, biomass-derived γ-butyrolactam can be obtained from glutamic acid, which is industrially produced by fermenting biomass-derived glucose, through decarboxylation and cyclization using known methods. Biomass-derived ε-caprolactam can also be obtained by chemically converting phenol obtained from biomass-derived lignin or biomass-derived cyclohexane using known methods.

[0286] The aminocarboxylic acid is not particularly limited, but aminocarboxylic acids having 6 to 12 carbon atoms are preferred. Specifically, examples include 6-aminocaproic acid, 7-aminoheptanoic acid, 9-aminononanoic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid. Among these, 6-aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid are preferred, with 11-aminoundecanoic acid being more preferred.

[0287] Biomass-derived aminocarboxylic acid compounds can be produced by known methods. For example, biomass-derived 11-aminoundecanoic acid can be obtained by chemically converting a ricinoleic acid derivative obtained by chemically decomposing castor oil extracted from castor bean seeds.

[0288] Examples of diamines include aliphatic diamines, alicyclic diamines, and aromatic diamines.

[0289] Aliphatic diamines are not particularly limited, but linear aliphatic diamines having 2 to 20 carbon atoms are preferred. Specifically, examples include tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, nonamethylenediamine, decamethylenediamine, and dodecamethylenediamine. Among these, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, and decamethylenediamine are preferred.

[0290] The alicyclic diamines are not particularly limited, but examples include 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, bis(4-aminocyclohexyl)propane, bis(3-methyl-4-aminocyclohexyl)methane, 1,4-bis(aminomethyl)cyclohexane, norbornane dimethyleneamine, and bis(aminomethyl)decalin.

[0291] Aromatic diamines are not particularly limited, but examples include phenylenediamine, xylylenediamine, tolylenediamine, diaminonaphthalene, diaminodiphenylmethane compounds, and bis(aminophenyl)propane compounds.

[0292] Biomass-derived diamines can be produced by known methods. For example, biomass-derived pentamethylenediamine can be obtained by decarboxylating biomass-derived lysine. Maize-derived pentamethylenediamine is also known. Biomass-derived hexamethylenediamine can be obtained by chemically converting biomass-derived adipic acid (described later) using known methods. Biomass-derived decamethylenediamine can be obtained from castor oil.

[0293] Examples of dicarboxylic acids include aliphatic dicarboxylic acids, alicyclic dicarboxylic acids, and aromatic dicarboxylic acids.

[0294] The aliphatic dicarboxylic acid is not particularly limited, but aliphatic linear dicarboxylic acids having 2 to 20 carbon atoms are preferred. Specifically, examples include adipic acid, azelaic acid, sebacic acid, undecanediic acid, and dodecanediic acid. Among these, adipic acid, sebacic acid, and dodecanediic acid are preferred.

[0295] Alicyclic dicarboxylic acids are not particularly limited, but examples include 1,4-cyclohexanedicarboxylic acid, dicyclohexanemethane-4,4'-dicarboxylic acid, and norbornanedicarboxylic acid.

[0296] Aromatic dicarboxylic acids are not particularly limited, but examples include phthalate compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid; naphthalenedicarboxylic acid and diphenylmethanedicarboxylic acid are examples, with terephthalic acid being preferred.

[0297] Biomass-derived dicarboxylic acids can be produced by known methods.

[0298] For example, biomass-derived adipic acid can be obtained by synthesizing a mixture of cyclohexanone and cyclohexanol from phenol obtained from biomass-derived lignin or biomass-derived cyclohexane, and then oxidizing it by a known method (e.g., nitric acid oxidation). Alternatively, it can be obtained by generating adipic acid intermediate through microbial fermentation of sugars obtained from non-edible components of plants, and then chemically converting it.

[0299] Biomass-derived sebacic acid can be obtained by thermally decomposing castor oil with alkali.

[0300] Terephthalic acid derived from biomass can be produced by converting biomass-derived isobutanol to isobutylene, then dimerizing it to produce isooctene, and then synthesizing p-xylene via radical cleavage, recombination, and cyclization, as described in Chemische Technik, vol.38, No.3, pp.116-119; 1986, and then oxidizing it (International Publication No. 2009 / 079213). Isobutanol derived from biomass can be obtained by fermenting sugar solutions or starches obtained from plants such as maize with microorganisms such as yeast.

[0301] Examples of polyamides include aliphatic polyamides, semi-aromatic polyamides, and fully aromatic polyamides.

[0302] Examples of aliphatic polyamides include aliphatic homopolyamides and aliphatic copolymer polyamides. Aliphatic homopolyamides may be polyamides composed of one lactam or one aminocarboxylic acid, or polyamides composed of a combination of one aliphatic diamine and one aliphatic dicarboxylic acid. Aliphatic copolymer polyamides may be polyamides composed of two or more monomers selected from lactams and aminocarboxylic acids, or polyamides composed of a combination of lactam and / or aminocarboxylic acid, an aliphatic diamine and an aliphatic dicarboxylic acid, or polyamides composed of a combination of one or more aliphatic diamines and one or more aliphatic dicarboxylic acids (except for a combination of one aliphatic diamine and one aliphatic dicarboxylic acid).

[0303] Aliphatic homopolyamides include, specifically, (PA4), polycaprolactam (PA6), polyundecanelactam (PA11), polyhexamethyleneadipamide (PA66), polytetramethylenedecamide (PA410), polypentamethylenesebacamide (PA510), polypentamethylenedodecadamide (PA512), polyhexamethylenesebacamide (PA610), polyhexamethylenedodecadamide (PA612), polynonameethyleneadipamide (PA96), and polynonameethyleneazeramide (P Examples of A99 include polynonameethylene sebamid (PA910), polynonameethylene dodecamide (PA912), polydecamethylene adipamide (PA106), polydecamethylene azeramide (PA109), polydecamethylene decamid (PA1010), polydecamethylene dodecamide (PA1012), polidodecamethylene adipamide (PA126), polidodecamethylene azeramide (PA129), polidodecamethylene sebamid (PA1210), and polidodecamethylene dodecamide (PA1212).

[0304] Examples of aliphatic copolymer polyamides include caprolactam / hexamethylenediaminoadipic acid copolymer (PA6 / 66), caprolactam / hexamethylenediaminosebacic acid copolymer (PA6 / 610), caprolactam / hexamethylenediaminododecanoic acid copolymer (PA6 / 612), and caprolactam / hexamethylenediaminoadipic acid / hexamethylenediaminosebacic acid copolymer (PA6 / 66 / 610).

[0305] Semi-aromatic polyamides are polyamides having structural units derived from aromatic diamines and structural units derived from aliphatic dicarboxylic acids, or polyamides having structural units derived from aliphatic diamines and structural units derived from aromatic dicarboxylic acids. Examples include polyamides composed of aromatic diamines and aliphatic dicarboxylic acids, and polyamides composed of aliphatic diamines and aromatic dicarboxylic acids.

[0306] Polyamides composed of aromatic diamines and aliphatic dicarboxylic acids do not necessarily have to consist entirely of aromatic diamines, and may further contain constituent units derived from aliphatic diamines. Polyamides composed of aliphatic diamines and aromatic dicarboxylic acids do not necessarily have to consist entirely of aromatic dicarboxylic acids, and may further contain constituent units derived from aliphatic dicarboxylic acids. These polyamides may further contain constituent units derived from lactams and / or aminocarboxylic acids.

[0307] Examples of semi-aromatic polyamides include polytetramethylene terephthalamide (PA4T), polyhexamethylene terephthalamide (PA6T), polydecamethylene terephthalamide (PA10T), polyhexamethylene isophthalamide (PA6I), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (PA66 / 6T), polyhexamethylene terephthalamide / polycaproamide copolymer (PA6T / 6), polyhexamethylene isophthalamide / polyhexamethylene terephthalamide copolymer (PA6I / 6T), and polymetaxylylene adipamide (PAMXD6).

[0308] All aromatic polyamides are polyamides that have a skeleton in which aromatic rings are linked by amide bonds. Specific examples include poly(p-phenylene terephthalamide).

[0309] The code 31 may be a code formed solely from biomass polyamide fibers, or it may be a hybrid code in which filaments made of virgin polyamide fibers or other organic fibers are twisted together. The biomass polyamide fiber content in the code 31 can be 10 to 100% by mass (for example, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 99).

[0310] Radiocarbon (C14) is present at a certain concentration in bio-derived raw materials that grow by absorbing carbon dioxide from the atmosphere, but it is almost absent in petroleum trapped underground. Therefore, by measuring the concentration of C14 present in organic fiber cords using accelerator mass spectrometry, it is possible to obtain an indicator (biomass content) of the proportion of bio-derived monomer units present in those organic fiber cords.

[0311] The biomass content of Code 31 can be 10-100% (for example, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 99).

[0312] The number of cords 31 per 50 mm in width perpendicular to the longitudinal direction of the cord 31 (also called ends) can be between 30 and 70 (for example, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68).

[0313] In Figures 8 and 9, one cord 31 is composed of two under-twisted yarns 33, but the invention is not limited to this configuration. The fineness of the under-twisted yarn 33 is preferably 500 dtex or more, preferably 700 dtex or more, more preferably 800 dtex or more, and particularly preferably 1000 dtex or more. Furthermore, the fineness of the under-twisted yarn 33 is preferably 3500 dtex or less, and more preferably 3000 dtex or less.

[0314] The total fineness of Code 31 is preferably 1000 dtex or more, more preferably 1400 dtex or more, more preferably 1600 dtex or more, and particularly preferably 2000 dtex or more. Furthermore, the total fineness of Code 31 is preferably 7000 dtex or less, more preferably 6500 dtex or less, and even more preferably 6000 dtex or less.

[0315] The average diameter D of the code 31 is not particularly limited, but is preferably 0.50 to 0.90 mm, more preferably 0.55 to 0.85 mm, and even more preferably 0.60 to 0.80 mm. The outer diameter d of the filament 34 is not particularly limited, but is preferably 15.0 to 30.0 μm, and more preferably 20.0 to 25.0 μm.

[0316] From the viewpoint of the effects of the present invention, D / d is preferably 30 or more, preferably 33 or more, and preferably 36 or more. On the other hand, from the viewpoint of cost, D / d is preferably 50 or less, and more preferably 45 or less.

[0317] The heat shrinkage rate of Code 31 is preferably 5.0% or less, more preferably 4.0% or less, and even more preferably 3.0% or less. Such a code does not shrink excessively even at high speeds, thereby improving handling stability.

[0318] The breaking strength of Code 31 is preferably 3.5 cN / dtex or higher, more preferably 4.0 cN / dtex or higher, even more preferably 4.5 cN / dtex or higher, even more preferably 5.0 cN / dtex or higher, even more preferably 5.5 cN / dtex or higher, and particularly preferably 6.0 cN / dtex or higher. There is no particular upper limit to this breaking strength.

[0319] The elongation at break of Code 31 is preferably 10% or more, preferably 11% or more, and more preferably 12% or more. There is no particular upper limit to this elongation at break.

[0320] The strength retention rate after pressurizing Code 31 at 135°C for 16 hours is preferably 80% or more, and more preferably 85% or more.

[0321] In the tire of the present invention, for tire members other than those comprising at least one ply having a cord containing biomass polyamide fibers, a cord other than the one containing biomass polyamide fibers can be used. Other cords include organic fiber cords that do not contain biomass polyamide fibers and steel cords.

[0322] The material of the steel filament forming the steel cord is not particularly limited, and materials such as HT (High Tensile), SHT (Super High Tensile), and UHT (Ultra High Tensile) can be used. Alternatively, recycled steel cord obtained by melting down used iron products may be used.

[0323] The steel cord may be coated with a plating layer. A steel cord with a plating layer exhibits high moisture-resistant thermal bonding performance even under harsh conditions of high temperature and humidity, thus preventing delamination between the topping rubber and the steel cord, and improving the durability of the tire under humid and hot conditions. Furthermore, if the steel cord has multiple filaments, a plating layer can be applied to the surface of each filament.

[0324] The plating layer can be formed by plating copper, zinc, and cobalt layers onto the filament before wire drawing, and then diffusing the metals of each layer formed on the filament surface by heat treatment. The order in which the layers are formed on the filament to create the plating layer is not particularly limited.

[0325] Furthermore, when using a cord made by twisting together multiple steel filaments in a tire component having a cord, it is also possible to use steel filaments that have been pre-curled in the longitudinal direction to improve durability by making it easier for the coating rubber layer to penetrate inside the cord.

[0326] Examples of steel cord structures include a 1×N structure in which N filaments are twisted together, an M×N structure in which M yarns, each made by twisting N filaments together, are twisted together, and an N+M structure in which M filaments are twisted around N core filaments.

[0327] Other organic fibers that make up organic fiber cords include virgin polyamide fibers, polyester fibers, and cellulose fibers. These may be synthetic fibers or biomass-derived fibers. Furthermore, from the viewpoint of life cycle assessment, it is preferable that they are derived from recycled or recycled materials. These fibers may also be formed from a single component of synthetic fibers, biomass-derived fibers, or recycled / recycled fibers, and may be hybrid cords made by twisting these together, cords using multifilaments made by combining the respective filaments, or cords having a chemical structure in which the respective components are chemically bonded.

[0328] The polyester constituting the polyester fiber can be obtained by known methods, for example, by polycondensation of a diol and a dicarboxylic acid or its derivative, in the presence of a conventional catalyst as needed. From the viewpoint of environmental impact, it is preferable to use diols and dicarboxylic acids derived from biomass.

[0329] Polyester may be recycled polyester obtained from used polyester articles. Examples of recycled polyester include mechanically recycled polyester and chemically recycled polyester.

[0330] Mechanically recycled polyester is polyester obtained by crushing and washing used polyester articles to remove contaminants and foreign matter, obtaining flakes, and then further treating the flakes under high temperature and reduced pressure. Because mechanical recycling allows for the production of recycled polyester without chemical decomposition, it tends to be less expensive than chemical recycling.

[0331] Chemically recycled polyester is a polyester obtained by chemically decomposing the aforementioned flakes back into monomer units, purifying them, and then repolymerizing them. Chemical recycling makes it possible to obtain polyester with physical properties and characteristics comparable to virgin polyester produced by conventional methods from dicarboxylic acids and diols derived from petroleum and other raw materials.

[0332] While there are no particular limitations on polyester, specific examples include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethylene furanoate (PEF), polytriethylene terephthalate, polybutylene terephthalate, and polybutylene naphthalate. PET is preferred from the viewpoint of cost, strength, and durability. In addition, PEF has superior air permeability resistance compared to other polyester cords and tends to maintain air pressure inside the tire more easily.

[0333] Examples of cellulose fibers include rayon, polynosic, cupro, acetate, lyocell, and modal, which are manufactured from plant materials such as wood pulp. These cellulose fibers are preferable because their raw materials are carbon neutral, they are biodegradable, and they do not emit harmful gases when incinerated after use, thus possessing excellent environmental performance. Among the above, rayon, polynosic, and lyocell are particularly preferred due to their balance of process efficiency, environmental friendliness, and mechanical strength.

[0334] The above-mentioned organic fiber cords (including biomass polyamide cords) may be formed by twisting together one or more filaments. For example, two 1100dtex multifilaments are combined (i.e., 1100dtex / 2), twisted 48 times / 10cm, and then these two under-twisted yarns are combined and twisted the same number of times in the opposite or same direction as the under-twist. Alternatively, two 1670dtex multifilaments are combined (i.e., 1670dtex / 2), twisted 40 times / 10cm, and then these two under-twisted yarns are combined and twisted.

[0335] Furthermore, the above-mentioned organic fiber cords (including biomass polyamide cords) are preferably treated with an adhesive layer beforehand to ensure good adhesion to the coating layer. Known adhesive layers can be used, such as treatment with resorcinol-formaldehyde-rubber latex (RFL), epoxy treatment with an adhesive composition containing sorbitol polyglycidyl ether and blocked isocyanate followed by RFL treatment, or treatment with an adhesive composition containing a halohydrin compound, a blocked isocyanate compound, and rubber latex.

[0336] Resorcinol-formaldehyde-rubber latex (RFL) is, for example, an adhesive composition containing natural rubber and / or synthetic rubber latex and a cocondensate of phenol-formaldehyde and resorcinol, as described in Japanese Patent Publication No. 48-11335. Such an adhesive composition can be produced, for example, by a manufacturing method that includes the steps of condensing phenol and formaldehyde in the presence of an alkaline catalyst, copolymerizing an aqueous phenol-formaldehyde resin solution with resorcinol, and mixing the resulting phenol-formaldehyde-resorcinol resin solution with latex rubber.

[0337] Examples of synthetic rubber latex include butadiene polymer latex, styrene / butadiene copolymer latex, isoprene polymer latex, butadiene / acrylonitrile copolymer latex, butadiene / vinylpyridine polymer latex, and butadiene / vinylpyridine / styrene copolymer latex.

[0338] The adhesive layer consisting of the above-mentioned resorcinol-formaldehyde-rubber latex (RFL) can be formed by applying RFL adhesive (such as by dipping the above-mentioned cord in RFL solution). The above-mentioned RFL adhesive is usually applied after twisting to obtain the fiber cord, but it may also be applied before or during twisting.

[0339] The composition of the above RFL adhesive is not particularly limited and may be selected as appropriate, but it is preferably a composition containing 0.1 to 10% by mass of resorcinol, 0.1 to 10% by mass of formalin, and 1 to 28% by mass of latex, and more preferably a composition containing 0.5 to 3% by mass of resorcinol, 0.5 to 3% by mass of formalin, and 10 to 25% by mass of latex.

[0340] Examples of heating methods in the heat treatment include drying the cord to which the RFL adhesive composition is attached at 100-250°C for 1-5 minutes, followed by further heat treatment at 150-250°C for 1-5 minutes. The heat treatment conditions after drying are preferably 180-240°C for 1-2 minutes.

[0341] Examples of heating methods in the heat treatment include drying the cord to which the RFL adhesive composition is attached at 100-250°C for 1-5 minutes, followed by further heat treatment at 150-250°C for 1-5 minutes. The heat treatment conditions after drying are preferably 180-240°C for 1-2 minutes.

[0342] Examples of sorbitol polyglycidyl ethers include sorbitol diglycidyl ether, sorbitol triglycidyl ether, sorbitol tetraglycidyl ether, sorbitol pentaglycidyl ether, sorbitol hexaglycidyl ether, or mixtures thereof, and may also include sorbitol monoglycidyl ether. Sorbitol polyglycidyl ether has a large number of epoxy groups in one molecule and can form a highly cross-linked structure.

[0343] The chlorine content of sorbitol polyglycidyl ether is preferably 9.6% by mass or less, more preferably 9.5% by mass or less, even more preferably 9.4% by mass or less, and particularly preferably 9.3% by mass or less. The lower limit of the chlorine content is not particularly limited, and is, for example, 1% by mass or more. In this invention, the chlorine content of sorbitol polyglycidyl ether can be determined by methods such as those described in JIS K 7243-3.

[0344] The chlorine content of sorbitol polyglycidyl ether can be reduced by reducing the amount of epichlorohydrin used in the synthesis of epoxy compounds, among other things.

[0345] Blocked isocyanates are compounds produced by the reaction of an isocyanate compound with a blocking agent, and are temporarily inactivated by a group derived from the blocking agent. When heated at a predetermined temperature, the group derived from the blocking agent dissociates, generating an isocyanate group.

[0346] Examples of isocyanate compounds include those having two or more isocyanate groups in the molecule. Examples of diisocyanates having two isocyanate groups include hexamethylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, isophorone diisocyanate, phenylene diisocyanate, tolylene diisocyanate, trimethylhexamethylene diisocyanate, metaphenylene diisocyanate, naphthalene diisocyanate, diphenyl ether diisocyanate, diphenylpropane diisocyanate, biphenyl diisocyanate, and their isomers, alkyl-substituted compounds, halides, hydrogenated compounds to the benzene ring. In addition, triisocyanates having three isocyanate groups, tetraisocyanates having four isocyanate groups, and polymethylene polyphenyl polyisocyanate can be used. These isocyanate compounds can be used individually or in combination of two or more. Among these, tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, and polymethylene polyphenyl polyisocyanate are preferred.

[0347] Examples of blocking agents include lactam-based agents such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propiolactam; phenol-based agents such as phenol, cresol, resorcinol, and xylenol; alcohol-based agents such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, and benzyl alcohol; oxime-based agents such as formamidexime, acetaldehydexime, acetoxime, methyl ethyl ketoxime, diacetyl monooxime, benzophenone oxime, and cyclohexanone oxime; and active methylene-based agents such as dimethyl malonate, diethyl malonate, ethyl acetoacetate, methyl acetoacetate, and acetylacetone. Among these, lactam-based, phenol-based, and oxime-based blocking agents are preferred.

[0348] In the adhesive composition containing the above-mentioned sorbitol polyglycidyl ether and blocked isocyanate, the content of the blocked isocyanate is preferably 50 parts by mass or more, more preferably 200 parts by mass or more, per 100 parts by mass of sorbitol polyglycidyl ether. The upper limit is preferably 500 parts by mass or less, more preferably 400 parts by mass or less.

[0349] The adhesive composition containing the above-mentioned sorbitol polyglycidyl ether and blocked isocyanate may optionally contain the following components: for example, epoxy compounds other than sorbitol polyglycidyl ether, resins copolymerizable with sorbitol polyglycidyl ether, curing agents other than blocked isocyanates, organic thickeners, antioxidants, light stabilizers, adhesion enhancers, reinforcing agents, softeners, colorants, leveling agents, flame retardants, and antistatic agents.

[0350] Examples of epoxy compounds other than sorbitol polyglycidyl ether include glycidyl ethers such as ethylene glycol glycidyl ether, glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, bisphenol A diglycidyl ether, bisphenol S diglycidyl ether, novolac glycidyl ether, and brominated bisphenol A diglycidyl ether; glycidyl esters such as hexahydrophthalate glycidyl ester and dimer acid glycidyl ester; and triglycerides. Examples include glycidylamines such as glycidyl isocyanurate, glycidylhindantoin, tetraglycidyldiaminodiphenylmethane, triglycidylparaaminophenol, triglycidylmetaaminophenol, diglycidylaniline, diglycidyltoluidine, tetraglycidylmetoxylendiamine, diglycidyltribromaniline, and tetraglycidylbisaminomethylcyclohexane; and alicyclic or aliphatic epoxides such as 3,4-epoxycyclohexylmethylcarboxylate, epoxidized polybutadiene, and epoxidized soybean oil.

[0351] Treatment with the adhesive composition containing the above-mentioned sorbitol polyglycidyl ether and blocked isocyanate includes treatments performed to adhere the various components contained in RFL to the cord, and, if necessary, subsequent heat treatments.

[0352] Any method of application can be used, such as coating with a roller, spraying from a nozzle, or immersion in a bath solution (adhesive composition). From the viewpoint of uniform application and removal of excess adhesive, application by immersion is preferred.

[0353] Furthermore, to adjust the amount of material adhering to the cord, additional methods such as squeezing with a pressure roller, scraping with a scraper, blowing with compressed air, suction, and beating with a beater may be employed.

[0354] The amount adhering to the cord is preferably 1.0% by mass or more, more preferably 1.5% by mass or more, and also preferably 3.0% by mass or less, more preferably 2.5% by mass or less. The amount of adhesive adhering to the cord is the amount of solid content in the RFL adhesive adhering to 100 parts by mass of the cord.

[0355] The total solid content concentration of the adhesive composition containing the above-mentioned sorbitol polyglycidyl ether and blocked isocyanate is preferably 0.9% by mass or more, more preferably 14% by mass or more, and also preferably 29% by mass or less, more preferably 23% by mass or less.

[0356] In addition to resorcinol, formalin, and rubber latex, the adhesive composition containing the above-mentioned sorbitol polyglycidyl ether and blocked isocyanate may also contain vulcanization modifiers, zinc oxide, antioxidants, defoaming agents, etc.

[0357] Examples of heating methods in the heat treatment include drying the reinforcing material 16 to which the RFL adhesive composition is attached at 100-250°C for 1-5 minutes, and then further heat-treating it at 150-250°C for 1-5 minutes. The conditions for the heat treatment after drying are preferably 180-240°C for 1-2 minutes.

[0358] The adhesive composition containing the above-mentioned halohydrin compound, blocked isocyanate compound, and rubber latex is not particularly limited as long as it contains these components, but an adhesive composition containing the halohydrin compound, blocked isocyanate compound, and rubber latex, and not containing resorcinol and formaldehyde, is preferred.

[0359] Examples of halohydrin compounds include compounds obtained by reacting polyol compounds with epihalohydrin compounds (halohydrin ethers). Polyol compounds are compounds having two or more hydroxyl groups in their molecule. Examples include glycols such as ethylene glycol, propylene glycol, polyethylene glycol, and polypropylene glycol; hydroxyl acids such as erythritol, xylitol, sorbitol, and tartaric acid; glyceric acid, glycerin, diglycerin, polyglycerin, trimethylolpropane, trimethylolethane, and pentaerythritol. Examples of epihalohydrin compounds include epichlorohydrin and epibromohydrin.

[0360] Examples of halohydrin compounds include fluoroalcohol compounds, chlorohydrin compounds, bromohydrin compounds, and iodohydrin compounds. Among these, halogenated sorbitol and halogenated glycerol are preferred.

[0361] The halogen content in 100% by mass of the halohydrin compound is preferably 5.0 to 15.0% by mass, more preferably 7.0 to 13.0% by mass, and even more preferably 9.0 to 12.0% by mass.

[0362] Examples of blocked isocyanate compounds include those similar to the blocked isocyanates mentioned above. Similarly, examples of rubber latex include those similar to the rubber latex mentioned above.

[0363] The adhesive composition containing the above-mentioned halohydrin compound, blocked isocyanate compound, and rubber latex preferably contains 10.0 to 30.0 parts by mass of the halohydrin compound, 10.0 to 30.0 parts by mass of the blocked isocyanate compound, and 80.0 to 240.0 parts by mass of rubber latex. Furthermore, the adhesive composition does not contain resorcinol or formaldehyde.

[0364] An adhesive layer comprising an adhesive composition containing the above-mentioned halohydrin compound, blocked isocyanate compound, and rubber latex is formed on the surface of the cord using the adhesive composition. The adhesive layer is formed by, for example, dipping, brushing, casting, spraying, roll coating, knife coating, etc.

[0365] [Rubber composition for tire components] The rubber composition for tire components related to the present invention (hereinafter referred to as the rubber composition of the present invention) will now be described. Unless otherwise specified, it can be used in common with any tire component, such as each rubber layer of the tread, belt topping rubber, band topping rubber, sidewall, bead portion, clinch, and inner liner.

[0366] ≪Rubber components≫ The rubber composition of the present invention contains a rubber component. Preferably, the rubber component contains a diene rubber. Any diene rubber commonly used in the tire industry can be suitably used. Specifically, examples include isoprene rubber, butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile-butadiene rubber (NBR), etc. These diene rubbers may be used individually or in combination of two or more.

[0367] The rubber component is a component that contributes to crosslinking, and generally refers to a polymer with a weight-average molecular weight (Mw) of 10,000 or more that is not extracted by acetone. The rubber component is in a solid state at room temperature (25°C).

[0368] (Isoprene rubber) As isoprene-based rubbers, for example, isoprene rubber (IR) and natural rubber, which are common in the tire industry, can be used. Natural rubber includes 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), high-purity natural rubber, and grafted natural rubber. These isoprene-based rubbers may be used individually or in combination of two or more types.

[0369] NR is not particularly limited and can be any that is common in the tire industry, such as SIR20, RSS#3, TSR20, etc.

[0370] Furthermore, natural rubber derived from Russian dandelion or guayule may be used as NR. Compared to natural rubber derived from Hevea, natural rubber derived from Russian dandelion and guayule has a higher weight-average molecular weight and contains a large amount of high molecular weight components, so it tends to improve the fracture strength of the rubber. For the same reason, it is also thought that the strength at the adhesive part between the cord and the rubber will be stronger. In addition, these natural rubbers have a lower degree of branching and contain a large amount of linear polymers compared to natural rubber derived from Hevea, so the Rz of the polymer is large. Therefore, it is thought that the entanglement between polymers increases due to the large Rz of the polymer, and the interaction with the filler increases due to the increased probability of contact between the polymer and the filler, which is thought to improve reinforcement and improve resistance to flexural crack growth.

[0371] The isoprene-based rubber content in the rubber component can be 0 to 100% by mass (for example, 1, 3, 5, 7, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 99).

[0372] (BR) BR is not particularly limited, and for example, 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 synthesized using a rare-earth element catalyst (rare-earth BR), BR containing syndiotactic polybutadiene crystals (SPB-containing BR), modified BR (high-cis modified BR, low-cis modified BR), etc., which are common in the tire industry, can be used. These BRs may be used individually or in combination of two or more types.

[0373] High-cis BR can be commercially available from companies such as Nippon Zeon Co., Ltd., UBE Corporation, and JSR Corporation. Including high-cis BR can improve low-temperature properties and wear resistance. The cis content of high-cis BR is preferably 95 mol% or more, more preferably 96 mol% or more, and even more preferably 97 mol% or more. The cis content of BR is measured by the measurement method described above.

[0374] When BR is included, its content in the rubber component can be 0 to 100% by mass (for example, 1, 3, 5, 7, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 99).

[0375] (SBR) There are no particular limitations on SBR, and examples include solution-polymerized SBR (S-SBR), emulsion-polymerized SBR (E-SBR), and modified SBRs thereof (modified S-SBR, modified E-SBR). Modified SBRs include SBRs in which the terminals and / or main chain are modified, and modified SBRs coupled with tin, silicon compounds, etc. (condensates, those with branched structures, etc.). Furthermore, hydrogenated versions of these SBRs (hydrogenated SBRs) can also be used. These SBRs may be used individually or in combination of two or more types.

[0376] Furthermore, biomass-derived SBR polymerized using biomass-derived styrene and / or butadiene can also be used as SBR. Biomass-derived SBR is not only preferable from a life cycle assessment perspective, but also tends to have improved fracture resistance and other properties.

[0377] For the SBR, either oil-expanded SBR or non-oil-expanded SBR can be used. SBRs that can be used in this invention are commercially available from companies such as JSR Corporation, Sumitomo Chemical Co., Ltd., UBE Corporation, Asahi Kasei Corporation, ZS Elastomer Corporation, and ARLANXEO.

[0378] The styrene content of SBR can be 5% to 90% by mass (for example, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88). The styrene content of SBR is measured by the measurement method described above.

[0379] The vinyl content of SBR can be 5 mol% to 90 mol% (for example, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88). The vinyl content of SBR is measured by the measurement method described above.

[0380] When SBR is included, its content in the rubber component can be 0 to 100% by mass (for example, 1, 3, 5, 7, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 99).

[0381] The content of diene rubber in the rubber component is preferably 50% by mass or more (for example, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 98, 100).

[0382] (Non-diene rubber) The rubber component may include non-diene rubber. Examples of non-diene rubbers include butyl rubber (IIR), hydrogenated nitrile rubber (HNBR), ethylene propylene rubber, silicone rubber, polyethylene chloride rubber, fluororubber (FKM), acrylic rubber (ACM), and hydrin rubber. Non-diene rubber may be used alone or in combination of two or more types.

[0383] (Butyl rubber) Among the other rubber components mentioned above, examples of butyl-based rubbers include non-halogenated butyl rubber (regular butyl rubber, IIR), halogenated butyl rubbers such as brominated butyl rubber (Br-IIR) and chlorinated butyl rubber (Cl-IIR) (X-IIR), and copolymers of isobutylene and p-alkylstyrene.

[0384] When non-diene rubber is included, its content in the rubber component can be 0 to 100% by mass (for example, 1, 3, 5, 7, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 92, 95, 99).

[0385] In the case of rubber compositions used for each rubber layer of the tread, belt topping rubber, band topping rubber, sidewall, bead portion, and clinch, it is preferable that the rubber component contains a rubber component selected from the group consisting of isoprene-based rubber, BR, and SBR. In the case of rubber compositions used for inner liners, it is preferable that the rubber component contains a rubber component selected from the group consisting of isoprene-based rubber, BR, CR, and non-diene-based rubber. Here, butyl-based rubber is preferred as the non-diene-based rubber.

[0386] ≪Filler≫ The rubber composition of the present invention preferably contains a filler. Suitable fillers include those commonly used in the tire industry, such as silica, carbon black, as well as aluminum hydroxide, alumina (aluminum oxide), clay, calcium carbonate, mica, and biochar (BIO CHAR). The filler may be used alone or in combination of two or more.

[0387] <Silica> The silica used is not particularly limited; for example, silica prepared by the dry process (anhydrous silica) and silica prepared by the wet process (hydrated silica), which are common in the tire industry, can be used. Among these, hydrated silica prepared by the wet process is preferred because it contains a large number of silanol groups. In addition to these silicas, silica made from biomass materials such as rice husks can also be used. Silica may be used alone or in combination of two or more types.

[0388] In addition to the above, silica derived from biomass materials such as rice husks may also be used, from the perspective of life cycle assessment.

[0389] The specific surface area (N2SA) of silica for nitrogen adsorption is 50 m². 2 / g~500m 2 The value can be set to / g (for example, 80, 100, 120, 150, 180, 200, 220, 250, 280, 300, 350, 400). The N2SA of silica is measured by the measurement method described above.

[0390] The average primary particle diameter of silica can be 5 nm to 300 nm (for example, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 220, 250, 280). The average primary particle diameter of silica is measured by the measurement method described above.

[0391] The silica content per 100 parts by mass of rubber component can be 0 to 200 parts by mass (for example, 1, 3, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200).

[0392] <Carbon Black> The carbon black used is not particularly limited and can be any that is common in the tire industry, such as GPF, FEF, HAF, ISAF, SAF, etc. Specifically, N110, N115, N120, N125, N134, N135, N219, N220, N231, N234, N293, N299, N326, N330, N339, N343, N347, N351, N356, N358, N375, N539, N550, N582, N630, N642, N650, N660, N683, N754, N762, N765, N772, N774, N787, N907, N908, N990, N991, etc. can be suitably used, as can other proprietary synthetic products. Commercially available products include those from Asahi Carbon Co., Ltd., Cabot Japan Co., Ltd., Tokai Carbon Co., Ltd., Mitsubishi Chemical Corporation, Lion Corporation, Shin-Nippon Chemical Carbon Co., Ltd., and Columbia Carbon Corporation. These can be used individually or in combination of two or more types.

[0393] In addition to the above, carbon black may also be used, from the perspective of life cycle assessment, such as carbon black made from biomass materials like lignin, or recovered carbon obtained by thermally decomposing and refining products containing carbon black, such as tires.

[0394] In this specification, "recovered carbon black" refers to carbon black obtained by crushing used tires and other products containing carbon black and calcining the crushed material, wherein, according to the thermogravimetric method compliant with JIS K 6226-2:2003, when oxidative combustion occurs by heating in air, the proportion of the mass of ash (ash content), which is the component that does not burn, is 13% by mass or more. In other words, the proportion of the mass (carbon content) lost due to the aforementioned oxidative combustion of the recycled carbon black is 87% by mass or less. Recovered carbon black is also called recycled carbon black and is sometimes represented as rCB.

[0395] As the carbon black, a carbon black containing preferably 1% by mass or more of zinc may be used. When such a zinc-containing carbon black is used, the resulting rubber composition tends to have excellent strength and peel resistance. This is thought to be because the zinc component in the carbon black is mainly present as zinc oxide, contributing to uniform vulcanization. Such a zinc-containing carbon black is not particularly limited, but the aforementioned rCB can be cited as an example.

[0396] The specific surface area (N2SA) of carbon black for nitrogen adsorption is 50 m². 2 / g~500m 2 The value can be set to / g (for example, 80, 100, 120, 150, 180, 200, 220, 250, 280, 300, 350, 400). The N2SA of carbon black is measured by the measurement method described above.

[0397] The carbon black content per 100 parts by mass of rubber component can be 0 to 200 parts by mass (for example, 1, 3, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200).

[0398] The average primary particle size of carbon black can be 5 nm to 300 nm (for example, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 220, 250, 280). The average primary particle size of carbon black is measured by the measurement method described above.

[0399] <Other fillers> When fillers other than silica and carbon black are included, the total content of other fillers relative to 100 parts by mass of rubber component can be 0 to 100 parts by mass (for example, 1, 3, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95).

[0400] <<Other compounding agents>> In addition to rubber components and fillers, the rubber composition according to this embodiment may appropriately contain compounding agents commonly used in the tire industry, such as softeners, waxes, stearic acid, zinc oxide, antioxidants, vulcanizing agents, and vulcanization accelerators.

[0401] <Softener> The rubber composition of the present invention may contain a softening agent. Examples of softening agents include resin components, oils, liquid rubber, and ester-based plasticizers. Softening agents may also include stretching oils, stretching resins, and stretching liquid rubber components of rubber components that have been stretched using oil stretching, resin stretching, or liquid rubber stretching. These softening agents may be derived from petroleum or biomass. Furthermore, low molecular weight hydrocarbon components obtained by thermal decomposition and extraction of used tires or products containing various components may be used as softening agents.

[0402] (Resin components) The rubber composition according to this embodiment may also contain a resin component. The resin component that can be used in this embodiment is not particularly limited, but resins commonly used in the tire industry can be used, such as C9 resins, C5 resins, C5C9 resins, dicyclopentadiene resins, aromatic vinyl resins, coumarone resins, indene resins, terpene resins, rosin resins, phenolic resins, etc. These resin components may be used individually or in combination of two or more. Each resin component may also be used individually or in combination of two or more.

[0403] ≪C9 series resin≫ A "C9 resin" refers to a resin obtained by polymerizing a C9 fraction, and may be a polymer obtained by polymerizing the C9 fraction alone, or a copolymer obtained by copolymerizing the C9 fraction with other components. For example, a resin obtained by copolymerizing dicyclopentadiene (DCPD) and a C9 fraction is called a DCPD / C9 resin. Furthermore, the C9 resin may be a hydrogenated or modified version of these resins. Examples of C9 fractions include petroleum fractions with 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, coumarone, indene, methylindene, and dicyclopentadiene. As for C9 resins, commercially available products from companies such as BASF, Zeon Corporation, and ENEOS Corporation can be used.

[0404] ≪C5 series resin≫ "C5 resins" refer to resins obtained by polymerizing C5 fractions, and may be hydrogenated or modified versions of these resins. 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, and 1-pentene. As C5 resins, commercially available products from companies such as Structol, Nippon Zeon Co., Ltd., and ENEOS Corporation can be used.

[0405] ≪C5C9 resin≫ "C5C9 resin" refers to a resin obtained by copolymerizing the C5 fraction and the C9 fraction, and may be hydrogenated or modified. As C5C9 petroleum resin, commercially available products from companies such as Tosoh Corporation and LUHUA can be used.

[0406] <Dicyclopentadiene resins> A "dicyclopentadiene-based resin" refers to a resin in which cyclopentadiene (CPD) and / or dicyclopentadiene (DCPD) are the most abundant monomer components, and these may be hydrogenated or modified resins. Preferred dicyclopentadiene-based resins include polymers obtained by polymerizing only dicyclopentadiene as a monomer, and copolymers (DCPD / C9 resins) obtained by copolymerizing dicyclopentadiene with the C9 fraction. Commercially available dicyclopentadiene-based resins from companies such as ExxonMobil, ENEOS Corporation, Nippon Zeon Corporation, and Maruzen Petrochemical Co., Ltd. can be used.

[0407] Aromatic vinyl resin "Aromatic vinyl resin" refers to a resin in which aromatic vinyl compounds such as styrene, α-methylstyrene, vinyltoluene, and p-chlorostyrene are the most abundant monomer components, and these may be hydrogenated or modified. As aromatic vinyl resins, α-methylstyrene or a homopolymer of styrene or a copolymer of α-methylstyrene and styrene is preferred, and a copolymer of α-methylstyrene and styrene is more preferred, for reasons of being economical, easy to process, and having excellent heat generation properties. As aromatic vinyl resins, commercially available products from companies such as Kraton, Eastman Chemical Company, and Mitsui Chemicals, Inc. can be used.

[0408] Coumaron-based resin "Coumarone-based resin" refers to a resin containing coumarone as a monomer component, and may be hydrogenated or modified. Preferred coumarone-based resins include, for example, coumarone resin, which is a polymer with coumarone as the monomer component; coumarone-indene resin, which is a copolymer with coumarone and indene as monomer components; and coumarone-indene-styrene resin, which is a copolymer with coumarone, indene, and styrene as monomer components. As coumarone-based resins, commercially available products from companies such as Rutgers, Nippon Paint Chemical Co., Ltd., and Mitsui Chemicals, Inc. can be used.

[0409] Indene resin "Indene-based resin" refers to a resin containing indene as a monomer component, and may be hydrogenated or modified resins. Preferred indene-based resins include, for example, coumarone-indene resin, which is a copolymer of coumarone and indene as monomer components, and coumarone-indene-styrene resin, which is a copolymer of coumarone, indene, and styrene as monomer components. Commercially available indene-based resins from companies such as Rutgers, Nippon Paint Chemical Co., Ltd., and Mitsui Chemicals, Inc. can be used.

[0410] Terpene resins "Terpene resin" refers to a resin containing terpene compounds such as α-pinene, β-pinene, limonene, and dipentene as monomer components, and may be hydrogenated or modified. Preferred terpene resins include, for example, polyterpene resins, which are polymers in which one or more of the aforementioned terpene compounds are used as monomer components; aromatically modified terpene resins, which are copolymers in which the aforementioned terpene compounds and aromatic compounds are used as monomer components; and terpene phenol resins, which are copolymers in which the aforementioned terpene compounds and phenol compounds are used as monomer components. Examples of aromatic compounds that serve as monomer components in aromatically modified terpene resins include styrene, α-methylstyrene, vinyltoluene, and divinyltoluene. Examples of phenol compounds that serve as monomer components in terpene phenol resins include phenol, bisphenol A, cresol, and xylenol. As terpene resins, commercially available products from companies such as Yasuhara Chemical Co., Ltd., Arakawa Chemical Industries, Ltd., and Nippon Terpene Chemical Co., Ltd. can be used.

[0411] ≪Rosin-based resin≫ "Rosin-based resin" refers to a resin containing rosin acid compounds such as abietic acid, neoabietic acid, palastic acid, and isopimal acid, and may be hydrogenated or modified. Rosin-based resins are not particularly limited, but examples include natural resin rosin and rosin-modified resins obtained by hydrogenating, disproportionating, dimerizing, esterifying, etc. As rosin-based resins, commercially available products from companies such as Harima Chemical Industries, Ltd., Arakawa Chemical Industries, Ltd., and IREC Co., Ltd. can be used.

[0412] Phenolic resins "Phenol-based resins" refer to resins containing phenol compounds such as phenol and cresol as monomer components, and may also be hydrogenated or modified resins. Phenolic resins are not particularly limited, but examples include phenol-formaldehyde resins, alkylphenol-formaldehyde resins, alkylphenol-acetylene resins, oil-modified phenol-formaldehyde resins, and terpene-phenol resins. Phenolic resins that are commercially available from companies such as Sumitomo Bakelite Co., Ltd., DIC Corporation, and Asahi Organic Materials Co., Ltd. can be used.

[0413] When a resin component is included, its content relative to 100 parts by mass of rubber component can be 0 to 100 parts by mass (for example, 1, 3, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100).

[0414] (oil) Examples of oils include paraffinic process oils, naphthenic process oils, aromatic process oils, and vegetable oils. Furthermore, for environmental reasons, process oils with a low content of polycyclic aromatic compounds (PCA) can be used. Examples of low-PCA process oils include lightly extracted solvates (MES), processed distillate aromatic extracts (TDAEs), and heavy naphthenic oils. Additionally, from a life cycle assessment perspective, refined waste oil from rubber mixers and engines, or waste oil from cooking in restaurants, may be used.

[0415] In the present invention, "vegetable oil" refers to, for example, linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice oil, tall oil, sesame oil, perilla oil, castor oil, tung oil, pine oil, pine tar oil, sunflower oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, wood wax, etc. Furthermore, vegetable oils may also include refined oils obtained by refining the above oils (such as salad oil), transesterified oils obtained by transesterifying the above oils, hydrogenated oils obtained by hydrogenating the above oils, thermally polymerized oils obtained by thermally polymerizing the above oils, oxidized polymerized oils obtained by oxidizing the above oils, and waste cooking oils recovered from use as edible oils, etc. Vegetable oils may be liquid or solid at room temperature (25°C). These may be used individually or in combination of two or more types. Furthermore, the aforementioned vegetable oil is a component of the softening agent described later, and may be used in combination with other softening agents. Alternatively, some of the softening agent components in a known rubber composition may be replaced with these vegetable oils in equal amounts to satisfy the relationship of the present invention.

[0416] The vegetable oil according to this embodiment preferably contains acylglycerol, and more preferably contains triacylglycerol. In this specification, acylglycerol refers to a compound in which a hydroxyl group of glycerin and a fatty acid are ester-bonded. 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 of three or more. Note that acylglycerols of two or more forms can be obtained by thermal polymerization, oxidative polymerization, etc. Also, the acylglycerol may be a liquid or a solid at 25°C.

[0417] The method for confirming whether the rubber composition contains the acylglycerol is not particularly limited, 1This can be confirmed by ¹H-NMR measurement. For example, when a rubber composition containing triacylglycerol is immersed in deuterated chloroform at 25°C for 24 hours, and after removing the rubber composition, ¹H-NMR is measured at room temperature, and the tetramethylsilane (TMS) signal is set to 0.00 ppm, signals around 5.26 ppm, 4.28 ppm, and 4.15 ppm are observed. These signals are presumed to originate from hydrogen atoms bonded to carbon atoms adjacent to the oxygen atom of the ester group. In this paragraph, "around" refers to a range of ±0.10 ppm.

[0418] The aforementioned fatty acids are not particularly limited and may be unsaturated or saturated fatty acids. Examples of unsaturated fatty acids include monounsaturated fatty acids such as oleic acid, and polyunsaturated fatty acids such as linoleic acid and linolenic acid.

[0419] As for vegetable oils, commercially available products from companies such as Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo Co., Ltd., ENEOS Corporation, Orisoy Co., Ltd., H&R Co., Ltd., Toyokuni Oil Co., Ltd., Fuji Kosan Co., Ltd., and Nisshin Oillio Group Ltd. can be used.

[0420] When oil is included, the content of the rubber component per 100 parts by mass can be 0 to 100 parts by mass (for example, 1, 3, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100).

[0421] (Liquid rubber) Liquid rubber is not particularly limited as long as it is a polymer that is in a liquid state at 25°C, but examples include liquid butadiene rubber (liquid BR), liquid styrene butadiene rubber (liquid SBR), liquid isoprene rubber (liquid IR), liquid styrene isoprene rubber (liquid SIR), and liquid farnesene rubber. These liquid rubbers may be used individually or in combination of two or more.

[0422] The content of the softening agent per 100 parts by mass of the rubber component (total amount if multiple softening agents are used in combination) can be 0 to 200 parts by mass (for example, 1, 3, 5, 7, 8, 10, 12, 15, 17, 20, 22, 25, 28, 30, 32, 35, 37, 40, 42, 45, 47, 50, 52, 55, 57, 60, 62, 65, 68, 70, 72, 74, 76, 80, 82, 85, 88, 90, 95, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200).

[0423] While not particularly limited, examples of anti-aging agents include amine-based, quinoline-based, quinone-based, phenol-based, and imidazole-based compounds, as well as metal carbamate salts. Phenylenediamine-based anti-aging agents such as N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamine, N,N'-di-2-naphthyl-p-phenylenediamine, and N-cyclohexyl-N'-phenyl-p-phenylenediamine, and quinoline-based anti-aging agents such as 2,2,4-trimethyl-1,2-dihydroquinoline polymer and 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline are preferred. These anti-aging agents may be used individually or in combination of two or more.

[0424] When an anti-aging agent is included, its content per 100 parts by mass of rubber component can be 0.5 to 10.0 parts by mass (for example, 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5).

[0425] When wax is included, the amount of wax per 100 parts by mass of rubber component can be 0.5 to 10.0 parts by mass (for example, 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5).

[0426] When stearic acid is included, its content per 100 parts by mass of rubber component can be 0.5 to 10.0 parts by mass (for example, 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5).

[0427] When zinc oxide is included, its content per 100 parts by mass of rubber component can be 0.5 to 10.0 parts by mass (for example, 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5).

[0428] Crosslinking agent Sulfur is preferably used as a crosslinking agent. Suitable sulfur varieties include powdered sulfur, oil-treated sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, and highly dispersible sulfur.

[0429] When sulfur is included, its content per 100 parts by mass of rubber component can be 0.5 to 10.0 parts by mass (for example, 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5).

[0430] As a crosslinking agent other than sulfur, known organic crosslinking agents can also be used. The organic crosslinking agent is not particularly limited as long as it can form crosslinking chains other than polysulfide bonds, but examples include alkylphenol-sulfur chloride condensate, 1,6-hexamethylene-dithiosulfate sodium dihydrate, 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane, dicumyl peroxide, etc., with 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane being preferred. These organic crosslinking agents can be used if they are commercially available from companies such as Taoka Chemical Industries, Ltd., Lanxess Corporation, Flexis, etc.

[0431] The vulcanization accelerators are not particularly limited, but examples include sulfenamide, thiazole, thiuram, thiourea, guanidine, dithiocarbamate, aldehyde-amine or aldehyde-ammonia, imidazoline, and xanthate vulcanization accelerators. These vulcanization accelerators may be used individually or in combination of two or more.

[0432] Examples of sulfenamide-based vulcanization accelerators include N-tert-butyl-2-benzothiazolyl sulfenamide (TBBS), N-cyclohexyl-2-benzothiazolyl sulfenamide (CBS), and N,N-dicyclohexyl-2-benzothiazolyl sulfenamide (DCBS).

[0433] Examples of thiazole-based vulcanization accelerators include 2-mercaptobenzothiazole (MBT) or its salts, di-2-benzothiazolyl disulfide (MBTS), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, and 2-(2,6-diethyl-4-morpholinothio)benzothiazole.

[0434] Examples of thiram-based vulcanization accelerators include tetrakis(2-ethylhexyl)thiram disulfide (TOT-N), tetramethylthiram disulfide (TMTD), tetraethylthiram disulfide, tetramethylthiram monosulfide (TMTM), dipentamethylenethiram disulfide, and dipentamethylenethiram tetrasulfide.

[0435] Examples of thiourea-based vulcanization accelerators include thiourea compounds such as thiacarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, and dioltotrilthiourea, as well as N,N'-diphenylthiourea, trimethylthiourea, and N,N'-diethylthiourea.

[0436] Examples of guanidine-based vulcanization accelerators include 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, di-o-tolylguanidine salts of dicatecholborate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, and 1,3-di-o-cumenyl-2-propionylguanidine.

[0437] Examples of dithiocarbamate-based vulcanization accelerators include piperidinium pentamethylenedithiocarbamate (PPDC), zinc dimethyldithiocarbamate (ZnMDC), zinc diethyldithiocarbamate (ZnEDC), zinc dibutyldithiocarbamate (ZnBDC), zinc dibenzyldithiocarbamate (ZDBzC), zinc N-ethyl-N-phenyldithiocarbamate (ZnEPDC), zinc N-pentamethylenedithiocarbamate (ZnPDC), sodium dibutyldithiocarbamate (NaBDC), copper dimethyldithiocarbamate (CuMDC), iron dimethyldithiocarbamate (FeMDC), and tellurium diethyldithiocarbamate (TeEDC).

[0438] When a vulcanization accelerator is included, its content per 100 parts by mass of rubber component can be 0.5 to 10.0 parts by mass (for example, 0.5, 0.8, 1.0, 1.2, 1.5, 1.8, 2.0, 2.5, 2.8, 3.0, 3.2, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5).

[0439] [Manufacturing] The rubber composition of the present invention can be manufactured by known methods. For example, it can be manufactured by kneading each of the above components using a rubber kneading device such as an open roll or a closed kneader (Banbury mixer, kneader, etc.).

[0440] The mixing process includes, for example, a base mixing process in which compounding agents and additives other than the vulcanizing agent and vulcanization accelerator are mixed, and a final mixing (F mixing) process in which the vulcanizing agent and vulcanization accelerator are added to the mixture obtained in the base mixing process and mixed. Furthermore, the base mixing process can be divided into multiple processes as desired.

[0441] There are no particular limitations on the mixing conditions, but for example, in the base mixing process, mixing is performed at a discharge temperature of 150-170°C for 3-10 minutes, and in the final mixing process, mixing is performed at 70-110°C for 1-5 minutes. There are no particular limitations on the vulcanization conditions, but for example, vulcanization is performed at 150-200°C for 10-30 minutes.

[0442] The tire of the present invention, which is equipped with tire members made from the rubber composition of the present invention, can be manufactured by conventional methods. That is, an unvulcanized rubber composition prepared by blending each of the above components with the rubber component as needed is extruded to match the shape of each tire member, cords are embedded as needed, the resulting tire members are bonded together on a tire molding machine and molded in a conventional method to form an unvulcanized tire, and this unvulcanized tire is heated and pressurized in a vulcanizing machine to manufacture the tire. The vulcanization conditions are not particularly limited, but for example, a method of vulcanizing at 150 to 200°C for 10 to 30 minutes can be cited.

[0443] [Application] The tire of the present invention can be used for any application, regardless of whether it is a pneumatic or 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. A passenger car tire is a tire intended to be mounted on a four-wheeled vehicle and has a maximum load capacity of less than 1400 kg. A heavy-duty tire is a tire with a maximum load capacity of 1400 kg or more. In addition, the tire of the present invention can be used as an all-season tire, a summer tire, or a winter tire such as a studless tire. [Explanation of Symbols]

[0444] 1 tire 2 tread 2a Cap rubber 2b Base rubber 2c Conductive rubber component 3 Sidewall 4 Wing 5. Clinch 6. Bead section 6a Bead core 6b Bead Apex 6c bead reinforcement layer 7. Inner Liner 8 Carcass 8a Carcass ply 9 Belt Layer 9a Inner belt ply 9b Outer belt ply 10 bands (belt reinforcement layer) 10a Bandply 10b Edge Band Ply 11 Chafer 12 Circumferential groove 13. Transverse grooves (shoulder transverse grooves) 14 sipes (shoulder sipes) 15 sipes (center sipes) 16 Center Track and Field Club 17 Shoulder Track and Field Club 18 Yokomizo 19 Small hole 20 Inclined lateral grooves 21 Inclined joint groove 22 sipes 23 Side reinforcement layer 30 plies 31 Code 32 Topping Rubber 33 Pre-twisted yarn 34 filaments CL Tire Equator X Tire width direction Y Tire Radius Direction G T Tread thickness G TC Thickness of the cap rubber layer G TB Thickness of the base rubber layer D S Depth of the deepest part of the circumferential groove W S Maximum opening width in the tire width direction of the circumferential groove C S The angle that the longitudinal direction of the lateral groove makes with the tire width direction. W LS Width of the shoulder area G S Sidewall thickness G C Clinch thickness PC sidewall and clinch joint on the tire surface W9a Inner belt ply 9a width W9b Width of outer belt ply 9a Ht Tire section height H BE Belt layer height H K Height of the carcass fold H BA Bead apex height H C Clinch height Te tread contact point P1 First tread pattern section P2 Second tread pattern section

Claims

1. Tread and Sidewall and, A pair of bead sections, A tire comprising at least one tire member having a cord, A tire having at least one tire member having the aforementioned cord, the cord containing biomass polyamide fibers.

2. The tire according to claim 1, wherein the polyamide constituting the biomass polyamide fiber contains biomass-derived γ-butyrolactam or ε-caprolactam as a monomer component.

3. The tire according to claim 1 or 2, wherein the polyamide constituting the biomass polyamide fiber contains biomass-derived 11-aminoundecanoic acid as a monomer component.

4. The tire according to claim 1 or 2, wherein the polyamide constituting the biomass polyamide fiber contains biomass-derived pentamethylenediamine, hexamethylenediamine, or decamethylenediamine as a monomer component.

5. The tire according to claim 1 or 2, wherein the polyamide constituting the biomass polyamide fiber contains biomass-derived adipic acid, sebacitic acid, or terephthalic acid as a monomer component.

6. The tire according to claim 1 or 2, wherein the cord containing the biomass polyamide fibers has not been treated with a formalin-containing dipping solution.

7. The tire according to claim 1 or 2, wherein the tensile strength of the cord containing the biomass polyamide fiber is 5.5 cN / dtex or more.

8. The tire according to claim 1 or 2, wherein the elongation at break of the cord containing the biomass polyamide fiber is 10% or more.

9. The tire according to claim 1 or 2, wherein the strength retention rate of the cord containing the biomass polyamide fiber after being subjected to pressure treatment at 135°C for 16 hours is 80% or more.

10. The tire according to claim 1 or 2, wherein the cord containing the biomass polyamide fibers is covered with a topping rubber.

11. The tire according to claim 10, wherein the topping rubber contains carbon black containing 1% by mass or more of zinc element.

12. The tire according to claim 10, wherein the topping rubber contains natural rubber derived from Russian dandelion and / or guayule.

13. The tread is made of a rubber composition containing a rubber component, and the tread includes a cap rubber layer that constitutes the tread contact surface, and the tanδ of the cap rubber layer at 30°C (30°C tanδ T c) and the thickness G of the tread T Product of mm (30°C tanδ) T c×G T The tire according to claim 1 or 2, wherein the coefficient of gravity is 9.0 or less.

14. The tread is made of a rubber composition containing a rubber component, and the tread includes a cap rubber layer that forms the tread contact surface, and the thickness G of the tread T The complex modulus of elasticity of the cap rubber layer at 30°C relative to mm (30°C E* T c) Ratio (30℃E* T c / G T The tire according to claim 1 or 2, wherein the ratio is 0.2 or less.

15. The tire according to claim 1 or 2, wherein the land area ratio of the tread is 40% or more.

16. The sidewall is composed of a rubber composition containing a rubber component, and the tanδ (70°C tanδ s ) of the rubber composition is 0.03 or more and 0.20 or less. The tire according to claim 1 or 2.

17. The sidewall is made of a rubber composition containing a rubber component, and the complex modulus of elasticity of the rubber composition at 70°C (70°C E* s The tire according to claim 1 or 2, wherein the pressure is 2.5 MPa or more and 6.5 MPa or less.

18. The tire according to claim 1 or 2, wherein the ratio of the clinch height Hc mm to the tire cross-sectional height Wt mm (Hc / Ht) is 0.45 or less.

19. The clinch is made of a rubber composition containing a rubber component, and the tanδ of the rubber composition at 70°C (70°C tanδ c ) and the product of the clinch height Hcm (70°C tanδ c The tire according to claim 1 or 2, wherein ×Hc) is 0.6 or more and 14.0 or less.

20. The clinch is made of a rubber composition containing a rubber component, and the complex modulus of elasticity of the rubber composition at 70°C (70°C E*) is relative to the height Hcm of the clinch. c ) ratio (70℃E* c The tire according to claim 1 or 2, wherein the HC value is 0.07 or more and 0.75 or less.

21. The clinch is made of a rubber composition containing a rubber component, and when the complex modulus of elasticity of the rubber composition at 70°C is 70°CE*c, the thickness of the clinch G c The product of mm and 70°C E*c (G c ×70℃E* c The tire according to claim 1 or 2, wherein the ratio is 25 or more and 450 or less.

22. The bead portion comprises a bead apex, the bead apex is made of a rubber composition containing rubber components, and the tire radial height H of the bead apex BA mm and the tanδ of the rubber composition at 70°C (70°C BA ) and the product (H BA ×70°C tanδ BA The tire according to claim 1 or 2, wherein the coefficient of force is 0.3 or more and 12.0 or less.

23. The bead portion comprises a bead apex, the bead apex is made of a rubber composition containing rubber components, and the tire radial height H of the bead apex BA mm and the complex modulus of elasticity of the rubber composition at 70°C (70°C E* BA ) and the product (H BA ×70℃E* BA The tire according to claim 1 or 2, wherein the coefficient of force is 100 or more and 9000 or less.

24. The inner liner is made of a rubber composition containing rubber components, and the thickness G of the inner liner I mm and the tanδ of the rubber component at 70°C (70°C tanδ I ) product (G I ×70°C tanδ I The tire according to claim 1 or 2, wherein the coefficient of force is 0.02 or more and 1.40 or less.

25. At least one tire member having the aforementioned code is a band, The tire according to claim 1 or 2, wherein the band includes at least one band ply composed of a band cord containing biomass polyamide fibers and a topping rubber covering the band cord.

26. At least one tire member having the aforementioned code is a carcass, The tire according to claim 1 or 2, wherein the carcass includes at least one carcass ply composed of a carcass cord containing biomass polyamide fibers and a topping rubber covering the carcass cord.

27. The carcass ply comprises a main body portion extending from the tread through the sidewall to the bead portion, and a folded portion that is folded back at the bead portion and extends toward each sidewall portion, and has a contact area where the main body portion and the folded portion are in contact. The average diameter of the carcass cord is D. CA Let G be the interlayer rubber gauge between the carcass cord in the main body and the carcass cord in the folded portion in the contact area, and G / D CA The tire according to claim 26, wherein the ratio is 0.50 to 0.

60.

28. At least one tire member having the aforementioned code is a bead reinforcing layer, The tire according to claim 1 or 2, wherein the bead reinforcing layer comprises a bead reinforcing layer cord containing biomass polyamide fibers and a topping rubber covering the bead reinforcing layer.

29. The tire according to claim 1 or 2, further comprising a tire member having a recycled steel cord.

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