TIRES

Abstract

A tire that includes a tread section, wherein the tread section comprises one or more circumferential grooves, wherein the tread section is composed of a rubber composition comprising a rubber component and silicon dioxide, and a resin component, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, where the content of isoprene-based rubber in the rubber component is 40% by mass or more, where the styrene content S1 in mass % of the styrene-butadiene rubber is 30 or less, where the silicon dioxide content is 30 parts by mass or more based on 100 parts by mass of the rubber component, wherein the resin component comprises a dicyclopentadiene-based resin, where the amount of AE extractable by acetone is 16.0 or more in mass % of the rubber composition, where, if 30 °C-tanδ represents a tanδ at 30 °C of the rubber composition and T in mm represents a total thickness of the tread section, 30 °C-tanδ × T is less than 3.0, and where H in mm represents a groove depth of the deepest part of the circumferential groove, AE × H is 100.0 or more.

Description

TECHNICAL AREA

[0001] The present invention relates to a tire. BACKGROUND OF THE INVENTION

[0002] In general, a tire widely used for passenger cars and the like must exhibit both high levels of fuel efficiency and wet grip performance. For example, JP2006-307039 A discloses that a rubber composition comprising a styrene-butadiene rubber with a predetermined amount of vinyl and a butadiene rubber with a predetermined cis-1,4 bond content in a predetermined ratio is used to improve wet braking performance and rolling resistance. SUMMARY OF THE INVENTION

[0003] Recently, further improvements in fuel efficiency and wet grip performance of a tire have been requested.

[0004] One object of the present invention is to provide a tire that can improve overall fuel efficiency and wet grip performance.

[0005] The present invention relates to a tire comprising a tread section, wherein the tread section comprises one or more circumferential grooves, wherein the tread section is composed of a rubber composition comprising a rubber component and silicon dioxide, and a resin component, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, where the content of isoprene-based rubber in the rubber component is 40% by mass or more, where the styrene content S1 in mass % of the styrene-butadiene rubber is 30 or less, where the silicon dioxide content is 30 parts by mass or more based on 100 parts by mass of the rubber component, wherein the resin component comprises a dicyclopentadiene-based resin, where the amount of AE extractable by acetone is 16.0 or more in mass % of the rubber composition, where, if 30 °C-tanδ represents a tanδ at 30 °C of the rubber composition and T in mm represents a total thickness of the tread section, 30 °C-tanδ × T is less than 3.0, and where H in mm represents a groove depth of the deepest part of the circumferential groove, AE × H is 100.0 or more.

[0006] According to the present invention, the overall performance of fuel efficiency and wet grip can be improved. BRIEF DESCRIPTION OF THE FIGURES Fig.Figure 1 is a cross-sectional view passing through a tire rotation axis for a tire according to an embodiment of the present invention. Fig. Figure 2 is a cross-sectional view passing through a tire rotation axis for a tread section of a tire in relation to an embodiment of the present invention. Fig. Figure 3 is a schematic unfolded view of a running surface section, showing an embodiment of the present invention. Fig. Figure 4 is a cross-sectional view along a CC line of Fig. 3. DETAILED DESCRIPTION

[0007] A tire that is an embodiment of the present invention is a tire comprising a tread section, wherein the tread section comprises one or more circumferential grooves, wherein the tread section is composed of a rubber composition comprising a rubber component and silicon dioxide, and a resin component, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, wherein the content of the isoprene-based rubber in the rubber component is 40 wt% or more, wherein the styrene content S1 in wt% of the styrene-butadiene rubber is 30 or less, wherein the content of the silicon dioxide is 30 wt% or more based on 100 wt% of the rubber component, wherein the resin component comprises a dicyclopentadiene-based resin, wherein the amount of AE extractable by acetone in wt% of the rubber composition is 16.0 wt% or greater, wherein,where 30 °C-tanδ represents a tanδ at 30 °C of the rubber composition and T in mm represents a total thickness of the tread section, 30 °C-tanδ × T is less than 3.0 and where H in mm represents a groove depth of a deepest part of the circumferential groove, AE × H is 100.0 or more.

[0008] Although the following assumption is not intended to be bound to any particular theory, one reason why the overall performance of fuel efficiency and wet grip performance is improved in a tire of the present invention is assumed to be as follows.

[0009] In the rubber composition forming the tread section of the tire according to the present invention, (1) if the content of an isoprene-based rubber with weak interaction with silicon dioxide is 40% by mass or more, a polymer phase in the rubber composition can move flexibly, and the motility of the polymer is improved. As a result, the micro-tracking ability towards a road surface is improved, which contributes to improved wet grip performance. Furthermore, (2) if the styrene content S1 in wt% of the styrene-butadiene rubber is 30% or less, a tiny styrene domain is formed in the rubber matrix, and the tiny styrene domain moves flexibly, which contributes to a further improvement in the motility of the polymer phase in the rubber composition.Furthermore, (3) when the silicon dioxide content is 30 parts by mass or more, silicon dioxide aggregates form in a polymer phase, which contributes to a further improvement in wet adhesion performance.

[0010] Furthermore, in the rubber composition forming the tread section of the tire of the present invention, (4) if an acetone-extractable amount of AE of the rubber composition is 16.0 wt% or more, a plasticizer is included in the rubber composition to a certain extent, the dispersibility of silicon dioxide is improved, and the balance between fuel efficiency and wet grip performance is improved. In addition, (5) a dicyclopentadiene-based resin is compatible with an isoprene-based rubber, styrene, and a butadiene rubber, and thus the dispersibility of a polymer is improved, thereby improving the balance between fuel efficiency and wet grip performance.

[0011] In the tire of the present invention, (6) if 30 °C tanδ × T is less than 3.0, the tread thickness can be reduced to suppress heat accumulation, and heat generation by a tread rubber can be synergistically suppressed by reducing 30 °C tanδ. Furthermore, (7) if AE amount × H is 140.0 or more, the dispersion and distribution efficiency of a filler is good, so that the stiffness of the rubber composition can be reduced and the dispersibility of a polymer and the filler is improved, thereby improving fuel efficiency and wet grip performance. Then, with the interaction of (1) to (7) described above, it is assumed that a significant effect of improving the overall performance of fuel efficiency and wet grip is achieved.

[0012] From the perspective of fuel efficiency, the rubber composition preferably comprises 1 part by mass or more and 10 parts by mass or less of carbon black based on 100 parts by mass of the rubber component.

[0013] From the perspective of suppressing heat generation by the tread rubber, the tanδ at 30 °C is preferably 0.26 or less.

[0014] At 30 °C, tan δ × T is preferably less than 2.6 from the point of view of suppressing heat accumulation and heat generation by the tread rubber.

[0015] The total styrene content (S2) in the rubber component is preferably 15% by mass or less. When the total styrene content (S2) is 15% by mass or less, a tiny styrene domain is formed in the rubber matrix, and this tiny styrene domain exhibits flexibility. Therefore, the mobility of the polymer is improved, and the conformability of the rubber composition to a road surface is enhanced, so it is assumed that wet grip performance is further improved.

[0016] At 0°C, tan δ is preferably 0.45 or more from the point of view of wet adhesion performance.

[0017] S1 × R is preferably 11.0 or more. When S1 × R is 11.0 or more, a tiny styrene domain formed in a rubber phase moves flexibly, thereby improving the motility of a polymer, and a tread section whose tracking ability towards a road surface is improved has a large contact area with a road surface, so it is assumed that wet grip performance is further improved.

[0018] If G in kg represents the tire weight, S1 / G is preferably 3.0 or less. The lighter the tire, the smaller the force pressing the tread section against the road surface, and therefore it is assumed that as the tire becomes lighter, even a slight aggregation of the styrene portion has a greater effect on the tread surface. By reducing S1 as the tire weight decreases, heat generation can be reduced, thus further improving fuel efficiency.

[0019] From the point of view of the effects of the present invention, the dicyclopentadiene-based resin is preferably a resin comprising dicyclopentadiene, styrene and indene as monomer components.

[0020] It is preferred that the tread section has rib sections separated by one or more circumferential grooves, that the rib section has lateral grooves extending to an inside in a tire radial direction, and that at least one of the lateral grooves has a groove width on the inside in the tire radial direction that is wider than a groove width on a tread surface.

[0021] By arranging the lateral grooves on the web sections, an increase in compression stiffness can be suppressed, even as abrasion progresses, so that wet adhesion performance can be ensured.

[0022] If an area of ​​30% of a tread ground contact width centered on a tire equator is defined as a center area, and areas that are both outer sides of the center area and are within the tread ground contact width are defined as a pair of shoulder areas, then a groove depth of the deepest part of the circumferential groove present in the shoulder areas is preferably 6.0 mm or more.

[0023] The configuration described above can improve drainage performance, which is why it is believed to contribute to improved wet adhesion performance.

[0024] If t1 in mm represents the thickness of a layer of the tread section whose outer surface forms a tread surface, and B in mm represents the thickness of a belt layer of the tread section, then B is 0.9 or more and 1.2 or less, and t1 / B is preferably 7.0 or less.

[0025] If the thickness B of the belt layer is 0.9 mm or more, rubber degradation can be suppressed, thus further improving abrasion resistance. If the thickness B of the belt layer is 1.2 mm or less, heat generation by the rubber can be suppressed, thus improving fuel efficiency. If t1 / B is 7.0 or less, the thickness of the layer whose outer surface forms the tread surface can be reduced, thus reducing rolling resistance and improving adhesion performance.

[0026] The groove bottom thickness of the tread section is preferably 1.0 mm or more and 4.0 mm or less. If the groove bottom thickness is within the range described above, heat generation by the tread rubber can be suppressed, which is thought to contribute to improved fuel efficiency. [Definitions]

[0027] A “styrene content S1 in mass % of a styrene-butadiene rubber” is a styrene content in mass % of a styrene-butadiene rubber (SBR). In a case where a rubber component comprises only one SBR, S1 is a styrene content of the SBR, and in a case where the rubber component comprises multiple SBRs, S1 is calculated by the sum of a product of the styrene content of each SBR and a composite quantity in mass % of the SBR, where the total SBR is 100 mass %.

[0028] If the rubber component consists, for example, of 20 wt% of a first SBR (styrene content: 25 wt%), 30 wt% of a second SBR (styrene content: 27.5 wt%) and 50 wt% of a BR, the styrene content S1 of the styrene-butadiene rubber is 26.5 wt% (= (25 × 40 / 100) + (27.5 × 60 / 100)).

[0029] A "total styrene content S2 in mass % in the rubber component" is the total content in mass % of the styrene particles contained in 100 mass % of the rubber component, and is a value obtained by calculating, for each rubber component, a value obtained by multiplying a styrene content in mass % by a mass fraction in the rubber component, and then adding these values. Specifically, it is calculated as Σ (styrene content (mass %) of each styrene-containing rubber × content (mass %) of each styrene-containing rubber in the rubber component / 100).

[0030] If the rubber component consists, for example, of 20 wt% of a first SBR (styrene content: 25 wt%), 30 wt% of a second SBR (styrene content: 27.5 wt%), and 50 wt% of a BR, the total amount of styrene S2 in 100 wt% of the rubber component is approximately 13.3 wt% (=(25 × 20 / 100) + (27.5 × 30 / 100) + (0 × 10 / 100)).

[0031] An “acetone extractable amount (AE)” is a value calculated by the following equation by immersing each vulcanized rubber test piece in acetone at room temperature (around 25 °C) for 72 hours in accordance with JIS K 6229:2015 to extract a soluble component, and measuring the mass of each test piece before and after extraction. (Amount extractable by acetone (mass %)) = {(Mass of rubber test piece before extraction - Mass of rubber test piece after extraction) / (Mass of rubber test piece before extraction}) × 100.

[0032] A "glass transition temperature (Tg) of a rubber composition" is a temperature corresponding to a maximum value (tanδ peak temperature) within a range of -60 °C or higher and 40 °C or lower, based on a temperature distribution curve of tanδ obtained by measurement under conditions of a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ± 0.5%, and a temperature rise rate of 2 °C / min using a dynamic viscosity measuring device (e.g., EPLEXOR series, manufactured by gabo Systemtechnik GmbH). Furthermore, when measured in the range of -60 to 40 °C, if the tanδ value continues to gradually increase or decrease as the temperature rises, the glass transition temperature of the rubber composition should be 40 °C or -60 °C, respectively.Furthermore, in the range of -60 °C or higher and 40 °C or lower, if there are two or more points indicating the maximum value, the point with the lowest temperature shall be a glass transition temperature.

[0033] “30 °C-tanδ” is a loss tangent (tanδ) measured using a dynamic viscoelasticity measuring device (for example, the EPLEXOR series, manufactured by gabo Systemtechnik GmbH) under conditions of a temperature of 30 °C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain of ± 1%, and a strain mode. A sample for measuring 30 °C-tanδ is a vulcanized rubber compound with a length of 20 mm, a width of 4 mm, and a thickness of 1 mm. In a case where the sample is prepared by cutting it from a tire, the sample is cut from a tread section such that one of the tire's circumferential directions becomes a long side and the tire's radial direction becomes a thickness direction.

[0034] “0 °C-tanδ” is a loss tangent (tanδ) measured using a dynamic viscoelasticity measuring device (for example, the EPLEXOR series, manufactured by gabo Systemtechnik GmbH) under conditions of a temperature of 0 °C, a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ± 2.5%, and a strain mode. A sample for measuring 0 °C-tanδ is prepared in the same way as for 30 °C-tanδ.

[0035] A "tread section" is a section that forms a ground contact area of ​​a tire and is an element that, in relation to elements forming a tire skeleton with steel or textile material, such as a belt layer, a belt reinforcement layer, a carcass layer and the like, is located in a cross-section in a tire radial direction on an outside in the tire radial direction when the tire includes these elements.

[0036] A "standardized condition" is a condition in which the tire is mounted on a standardized rim, filled with air at a standardized internal pressure, and is not subjected to any load.

[0037] Unless otherwise specified, a “dimension of each part of a tire” is a value specified in a standardized state for one appearing on the outer surface of the tire, while for one present inside the tire, or for one on a tire cut surface, it is a value specified in a state in which, for example, the tire is cut along a plane containing a tire axis of rotation and the cut piece of tire is held to a rim width of a standardized rim.

[0038] A "standardized rim" is a rim within a standard system that includes a standard on which the tire is based, and which is defined by the standard for each tire. For example, "standardized rim" refers to a standard rim of an applicable size described in the "Jatma Year Book" of JATMA (The Japan Automobile Tire Manufacturers Association, Inc.), a "Measuring Rim" described in the "STANDARDS MANUAL" of ETRTO (The European Tyre and Rim Technical Organisation), or a "Design Rim" described in the "YEAR BOOK" of TRA (The Tire and Rim Association, Inc.), referenced in that order, and if an applicable size exists at the time of reference, the rim conforms to its standard.Furthermore, in the case of a tire that is not defined by the standard, the "standardized rim" refers to a rim with the narrowest rim width among rims that can be mounted on the tire, that can maintain internal pressure (that is, cause no air leakage between the rim and the tire), and that have the smallest rim diameter.

[0039] A “standardized internal pressure” is an air pressure in a standard system containing a standard on which the tire is based, defined by the standard for each tire. It refers, for example, to a “MAXIMUM AIR PRESSURE” in JATMA, “INFLATION PRESSURE” in ETRTO, or a maximum value described in the “TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES” table in TRA, to which reference is made in that order, as in the case of the standardized rim, and if there is an applicable size at the time of reference, the standardized internal pressure conforms to its standard.Furthermore, in the case of tires not defined by the standard, the standardized internal pressure should refer to a standardized internal pressure (250 kPa or more) of another tire size (specified in the standard) for which the standardized rim is described as a standard rim, and if several standardized internal pressures of 250 kPa or more are described, it should refer to a minimum value below that.

[0040] A "standardized load" is a load within a standard system that includes a standard on which the tire is based, defined by the standard for each tire. For example, a "MAXIMUM LOAD CAPACITY" for JATMA, a "LOAD CAPACITY" for ETRTO, or a maximum value described in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" table for TRA. Reference is made to this load in that order, as in cases of a standardized rim and standardized inflation pressure. If an applicable size exists at the time of reference, the load conforms to its standard. Then, in the case of tires not defined by the standard, a maximum load capacity W is specified. L , which is obtained through a different calculation than a standardized load defined.

[0041] A "maximum load capacity W" L “ is calculated using the following equation. “V” represents a virtual volume in mm³ 3The dimensions of a tire are represented as follows: "Dt" represents the tire's outer diameter in mm in a standardized state, "Ht" represents the tire's cross-sectional height in mm in a radial direction in a cross-section of the tire on a plane containing a tire axis of rotation, and "Wt" represents the tire's cross-sectional width in mm in the standardized state. If R represents the tire's rim diameter, Ht can be calculated using the following equation: (Dt - R) / 2. Wt is a value obtained by excluding any patterns, letters, or the like on the tire's sidewall. Furthermore, the maximum load capacity has the same meaning as the standardized load described above. WL=0.000011×V+175 V={(Dt / 2)2−(Dt / 2−Ht)2}×π×Wt

[0042] A "ground contact area" is a region of a tire tread that results from a contour when a tire is pressed against a ground. The ground contact area is obtained by mounting the tire on a standardized rim, inflating the tire to a standardized internal pressure, and allowing the tire to stand at 25°C for 24 hours. This is followed by applying ink to a tire tread surface, applying a standardized load (maximum load capacity) to the tire to press the tread surface perpendicularly onto cardboard (a camber angle of 0°), and transcribing the ink. A portion of the ground contact area is referred to as the "total ground contact area."The total ground contact area can be calculated as an average value of areas from five locations obtained by rotating the tire in 72-degree increments to perform the transcription operation described above at the five locations.

[0043] An "effective contact patch" is the area of ​​a tire's tread that makes contact with the ground when the tire is pressed against it. The effective contact patch is obtained by mounting the tire on a standardized rim, inflating the tire to a standardized internal pressure, and leaving it at 25°C for 24 hours. This is followed by applying ink to a tire tread surface, applying a standardized load (maximum load capacity) to the tire to press the tread surface perpendicularly onto cardboard (a camber angle of 0°), and transcribing the ink. A portion of the effective contact patch is referred to as the "effective contact area."The effective ground contact area can be calculated as an average value of the areas of five locations obtained by rotating the tire in 72-degree increments to perform the transcription process described above at the five locations.

[0044] A “lift ratio R” is calculated from the total ground contact area of ​​the ground contact zone and the effective ground contact area of ​​the effective ground contact zone using the following equation, Survey ratio = (effective ground contact area / total ground contact area).

[0045] A "groove" refers to a depression formed on the tread surface of a tire, extending radially towards the inside of the tire, and having a groove width (opening width) of 2.0 mm or more. A depression with a groove width (opening width) of less than 2.0 mm on a tread surface is called a "sipe".

[0046] A "circumferential groove" refers to a groove that extends continuously in one direction around the circumference of the tire. The circumferential groove can extend linearly along the circumference or it can extend in a wavy, sinusoidal, or zigzag pattern along the circumference.

[0047] A "groove depth H in mm of the deepest part of a circumferential groove" refers to the linear distance between a straight line connecting the ends of the groove on a tread surface and the deepest part of the groove in the tire's radial direction in a cross-section of a tire along a plane containing a tire axis of rotation. In cases where the groove depth varies in the tire's width direction and / or circumferential direction, the groove depth is defined as the maximum value of the straight line. Furthermore, a depth at a point of triple or multiple intersection where several grooves cross is excluded from being defined as a single groove depth in this description.

[0048] A “groove bottom thickness” refers to a thickness of rubber extending from the deepest part of a circumferential groove to a cord of a belt layer (or to a cord of a belt guard layer in a case where the belt guard layer has the cord) or a maximum thickness of the rubber if there are multiple grooves.

[0049] A "groove width" refers to the distance between groove walls. The groove width can be determined at specific positions along the direction of a groove running from a tread surface to a groove bottom.

[0050] A "widened groove" refers to a groove whose groove width on the inside in the tire radial direction is wider than a groove width on a tread surface (opening width).

[0051] A "total thickness T in mm of a tread section" is the thickness of a tread section measured along a normal on a tire equator in a cross-section of a tire along a plane containing a tire axis of rotation. In a case where a circumferential groove is included on the tire equator, the total thickness T is a thickness measured along a normal on the center section in one tire width direction of a rib section, which is one of rib sections present in the tire width direction on both side faces of the circumferential groove, and whose center section lies close to the tire equator in the tire width direction. Additionally, the total thickness T of the tread section is an average value of total tread section thicknesses calculated at five locations by rotating the tire in 72-degree increments in one circumferential direction.

[0052] A “thickness t1 in mm of a layer whose outer surface forms a tread surface” is the thickness of a rubber layer whose outer surface forms a tread surface, where the thickness of the rubber layer is measured along a normal on a tire equator in a cross-section of a tire along a plane containing a tire axis of rotation. In a case where a circumferential groove is included on the tire equator, the total thickness T is a thickness measured along a normal on the central section in the tire width direction of a rib section, where the central section of the rib section is closest to a tire equator in the tire width direction, of rib sections present on both side faces of the circumferential groove in the tire width direction.Furthermore, t1 is an average value of tread thicknesses calculated at the five locations by rotating the tire in 72-degree increments in a circumferential direction.

[0053] A "thickness B in mm of a belt layer" is the thickness of a belt layer in the tire radial direction at a tire equator in a cross-section of a tire along a plane that contains a tire axis of rotation. In a case where no belt layer is present at the tire equator, the thickness B is the thickness in a tire radial direction per layer at a tire center position of a belt layer whose center portion lies close to the tire equator in a tire width direction.

[0054] A "tire weight G in kg" refers to the weight of a single tire, excluding the weight of the rim. However, if a component consisting of a sponge and sealant, a sensor element, or the like is located within the tire lumen, then G is a weight that includes the weight of such a component.

[0055] A "tread section" means a part of a tread where a tire contacts the ground when the tire is pressed against the ground, which is a section of the tread that forms the effective ground contact area described above.

[0056] A “rubber component of a rubber composition” refers to a component that contributes to crosslinking in a rubber composition and generally has a weight-average molecular weight (Mw) of 10,000 or more.

[0057] A “glass transition temperature (Tg) of a rubber component” means a static glass transition temperature of each rubber component, calculated by a differential scanning calorimeter (for example, Q200, manufactured by TA Instruments Japan Inc.).

[0058] A "styrene content" is a value determined by 1 H-NMR measurement is calculated and applied to a rubber component with a repeating unit derived from styrene, such as an SBR and the like (styrene unit-containing rubber).

[0059] A “vinyl content (1,2-bonded butadiene unit amount)” is a value calculated by infrared absorption spectrometry in accordance with JIS K 6239-2:2017 and applied to a rubber component with a repeating unit derived from butadiene, such as an SBR, a BR and the like.

[0060] A “cis content (cis-1,4-bonded butadiene unit amount)” is a value calculated by infrared absorption spectrometry in accordance with JIS K 6239-2:2017 and is applied to a rubber component with a repeating unit derived from butadiene, such as a BR and the like.

[0061] A “weight-mean molecular weight (Mw)” can be calculated with respect to a standard polystyrene based on measurements obtained by gel permeation chromatography (GPC) (e.g., GPC-8000 series manufactured by Tosoh Corporation, detector: Differential refractometer, column: TSKGEL SUPERMULTIPORE HZ-M manufactured by Tosoh Corporation). For example, Mw is applied to an SBR, a BR, a plasticizer, and the like.

[0062] The specific nitrogen adsorption surface area (N2SA) of carbon black is measured according to JIS K 6217-2:2017. The specific nitrogen adsorption surface area (N2SA) of silicon dioxide is measured using a BET method according to ASTM D3037-93.

[0063] An "average primary particle size" is calculated as the arithmetic mean of the particle sizes of 400 particles photographed with a transmission or scanning electron microscope. Regarding particle size, in cases where the particle is substantially circular, the diameter of the circle is defined as the particle size; in cases where it is needle- or rod-shaped, a minor axis is defined as the particle size; and in other cases, an equivalent circular diameter calculated from an electron micrograph is defined as the particle size. The equivalent circular diameter is calculated as the positive square root of "4 × (particle area) / n". The average primary particle size is applied to silicon dioxide, carbon black, etc.

[0064] A "plasticizer content" also includes an amount of plasticizer contained in a stretched rubber component that has been previously stretched with the plasticizer, such as an oil, resin component, liquid rubber component, and the like. Furthermore, this also applies to an oil content, a resin component content, and a liquid rubber content; for example, in a case where the stretching component is oil, the stretching oil is included in the oil content.

[0065] A “softening point of a resin component” is specified as a temperature at which a ball falls when the softening point defined in JIS K 6220-1:2015 7.7 is measured using a ring-and-ball softening point measuring device. [Tires]

[0066] The tire according to the present embodiment is described below with reference to the drawings. Furthermore, the embodiment described below is merely an example, and the tire of the present invention is not limited to the embodiment described below.

[0067] Fig. Figure 1 represents a tire according to the present embodiment. Fig. Figure 1 shows part of a cross-section when a tire is cut along a plane containing a tire axis of rotation. Fig. 1 is a vertical direction, a tire radial direction; a horizontal direction is a tire axial direction; and a direction perpendicular to a paper surface is a tire circumferential direction. Fig. 1 The alternating long and short dash-dot line CL indicates a tire equator.

[0068] The tire of Fig.1 comprises a tread section 1 which comes into contact with the ground during driving, a pair of sidewall sections 2 which extend to an outside in a tire radial direction, and a pair of bead sections 3.

[0069] As in Fig.As shown in Figure 1, a belt layer 5 is provided on the inner side of the tread section 1 in the tire radial direction. A carcass 4 and an inner liner 7 are laminated to the lower part of the belt layer 5. Furthermore, a band layer 6 may be present between the tread section 1 and the belt layer 5. Each bead section 3 comprises a bead core 14 and a bead taper 13 extending from this core to the outer side in the tire radial direction. The bead taper 13 tapers outwards in the tire radial direction. A clinch section 10, which comes into contact with a rim 8 during mounting, is provided on the outer side of the carcass 4 in the bead section 3, and the clinch section 10 is made of a rubber compound comprising a rubber component. A rim bead 9 may be present between the clinch section 10 and the rim 8.

[0070] The tread section according to the present embodiment can be a tread section consisting of a single rubber layer, or it can be a tread section comprising a layer whose outer surface forms a tread surface (rubber top layer) and one or more rubber layers (inner rubber layer) located between the rubber top layer and a belt layer. Fig. The tread section comprises a rubber top layer 11 and a rubber base layer 12, which are laminated to the outside of the belt layer 5 in the tire radial direction. A double arrow t1 denotes a thickness of the rubber top layer 11, and a double arrow t2 denotes a thickness of the rubber base layer 12.

[0071] The thickness t1 of the rubber cover layer is preferably 3.0 mm or more, more preferably 3.5 mm or more, and even more preferably 4.0 mm or more, but is not particularly limited. Furthermore, t1 is preferably 10.0 mm or less, more preferably 9.5 mm or less, even more preferably 9.0 mm or less, and particularly preferably 8.5 mm or less.

[0072] The thickness t2 of the rubber base layer is preferably 0.8 mm or more, more preferably 1.0 mm or more, even more preferably 1.2 mm or more, and particularly preferably 1.4 mm or more, but is not particularly limited. Furthermore, t2 is preferably 5.0 mm or less, more preferably 4.0 mm or less, and even more preferably 3.0 mm or less.

[0073] A total thickness T of the tread section (t1 + t2 in Fig.1) is preferably 4.5 mm or more, more preferably 5.0 mm or more, still more preferably 5.5 mm or more, still more preferably 6.0 mm or more, and particularly preferably 6.5 mm or more. On the other hand, an upper limit of T is preferably 11.0 mm or less, more preferably 10.5 mm or less, still more preferably 10.0 mm or less, and particularly preferably 9.5 mm or less, but is not particularly restricted.

[0074] The thickness B of the belt layer 5 is preferably 0.6 mm or more, more preferably 0.8 mm or more, and even more preferably 0.9 mm or more. Furthermore, the thickness B of the belt layer 5 is preferably 1.5 mm or less, more preferably 1.2 mm or less, and even more preferably 1.1 mm or less.

[0075] From the perspective of reducing rolling resistance to improve adhesion performance, t1 / B is preferably 8.0 or less, more preferably 7.5 or less, and even more preferably 7.0 or less. Furthermore, t1 / B is preferably 2.0 or more, more preferably 2.5 or more, and even more preferably 3.0 or more. <<Laufflächenabschnitte> >

[0076] Fig. Figure 2 is a cross-sectional view showing a cross-section passing through a tire rotation axis of the tread section of the tire. Fig. 2. A vertical direction is a tire radial direction, a horizontal direction is a tire width direction, and a direction perpendicular to a paper surface is a tire circumferential direction. A center point in a tire width direction of a web section 20 is in Fig.2. A straight line denoted by the symbol P. A straight line denoted by the symbol N is a straight line (normal) that passes through point P and is perpendicular to a tangent plane at point P.

[0077] The tread section in relation to the present embodiment comprises at least one or more circumferential grooves 15. The tread section comprises web sections 20 which are separated by the circumferential grooves 15 in a tire width direction.

[0078] In Fig.2. The groove depth H of the deepest part of a circumferential groove 15 refers to a linear distance between a straight line 17 connecting the ends of a circumferential groove on a tread surface 16 and an extension line of the deepest part of the groove in a tire radial direction. Furthermore, in a case where several circumferential grooves 15 are provided, the groove depth H can, for example, be defined as a linear distance between the straight line 17 and an extension line 19 of the deepest part in the tire radial direction of a circumferential groove 15 (circumferential groove 15 on the left side in Figure 2). Fig. 1) defined by the deepest groove depth among the multiple circumferential grooves 15.

[0079] The groove depth H of the deepest part in the circumferential direction, from the perspective of abrasion resistance, is preferably 4.0 mm or more, further preferably 4.5 mm or more, even more preferably 5.0 mm or more, and particularly preferably 5.5 mm or more. Furthermore, from the perspective of wet adhesion performance, the groove depth H of the deepest part of the circumferential groove is preferably 10.0 mm or less, further preferably 9.5 mm or less, even more preferably 9.0 mm or less, and particularly preferably 8.5 mm or less.

[0080] As in Fig. 1 and Fig. As shown in Figure 2, the tread section can comprise a layer whose outer surface forms the tread surface 16 (rubber top layer 11) and a rubber base layer 12 which abuts the inside of the rubber top layer 11 in the radial direction. A Fig.The circumferential groove 15 shown on the left is formed such that the deepest part of the groove bottom of the circumferential groove 15 is located on the inside in the tire radial direction with respect to an outer surface of the rubber base layer 12. Specifically, the rubber base layer 12 has a recessed portion that is recessed on the inside with respect to the outer surface in the tire radial direction, and a portion of the rubber cover layer 11 is formed within the recessed portion of the rubber base layer 12 with a predetermined thickness. The circumferential grooves 15 are formed such that they extend beyond the outer surface of the rubber base layer 12 and enter the inside of the recessed portion of the rubber base layer 12. Furthermore, as shown in Figure 2, the circumferential grooves 15 can be further defined by the circumferential grooves 15. Fig. 2 Circumferential groove 15 shown on the right, at a groove depth which does not reach the outer surface of the rubber base layer 12, the circumferential grooves 15 are formed.

[0081] In the present description, a ‘rubber composition forming a tread section’ refers, in a case where a tread section consists of two or more layers, to a rubber composition forming a rubber top layer.

[0082] The amount of acetone extractable from a rubber composition forming the tread section, with regard to improving the dispersibility of silicon dioxide, is preferably 16.0 wt% or more, more preferably 16.5 wt% or more, and even more preferably 17.0 wt% or more. Furthermore, with regard to abrasion resistance, it is preferably 35.0 wt% or less, more preferably 33.0 wt% or less, and even more preferably 30.0 wt% or less.

[0083] From the perspective of fuel efficiency and wet grip performance, AE × H is preferably 100.0 or more, further preferably 102.0 or more, even more preferably 104.0 or more, and particularly preferably 106.0 or more. Furthermore, from the perspective of abrasion resistance, AE × H is preferably 200.0 or less, further preferably 180.0 or less, even more preferably 160.0 or less, and particularly preferably 140.0 or less.

[0084] The 30 °C tanδ of the rubber composition forming the tread section, with regard to wet grip performance, is preferably 0.12 or more, more preferably 0.15 or more, even more preferably 0.18 or more, and particularly preferably 0.20 or more. Furthermore, with regard to heat suppression by the rubber, it is preferably 0.34 or less, more preferably 0.30 or less, and even more preferably 0.26 or less.

[0085] The 0 °C tanδ of the rubber composition forming the tread section is, from the perspective of wet grip performance, preferably 0.30 or more, more preferably 0.35 or more, even more preferably 0.40 or more, and particularly preferably 0.45 or more. Furthermore, from the perspective of fuel efficiency, it is preferably 0.70 or less, more preferably 0.65 or less, and even more preferably 0.60 or less.

[0086] From the perspective of wet adhesion performance, the tanδ × T at 30 °C is preferably 0.5 or more, more preferably 0.8 or more, and even more preferably 1.0 or more. On the other hand, from the perspective of suppressing heat accumulation and heat generation by the tread rubber, the tanδ × T at 30 °C is less than 3.0, preferably less than 2.8, more preferably less than 2.6, and even more preferably 2.4 or less.

[0087] From the perspective of the effects of the present invention, the glass transition temperature (Tg) of the rubber composition forming the tread section is preferably higher than -45 °C, more preferably higher than -42 °C, and even more preferably higher than -40 °C. Furthermore, from the perspective of balancing fuel efficiency and wet grip performance, it is preferably lower than -20 °C, more preferably lower than -25 °C, and even more preferably lower than -30 °C.

[0088] Furthermore, each physical property of the rubber composition, such as 30 °C tanδ, 0 °C tanδ, Tg, and the like, can be suitably adjusted depending on the type or quantity of a rubber component, filler, plasticizer, and the like, as described below. For example, 30 °C tanδ can be adjusted depending on the type of resin component. <<Laufflächenprofil> >

[0089] Fig. Figure 3 is a view showing a tread profile of a tire in relation to an embodiment of the present invention. However, the tread profile of the tire according to the present embodiment is not the one shown in Figure 3. Fig. 3 is shown, limited. Fig.3 The tread surface has three circumferential grooves extending continuously in the tire's circumferential direction. Although one circumferential groove located in the center (middle circumferential groove) extends in a zigzag pattern, the present invention is not limited to this aspect, and the middle circumferential groove may be linear. Furthermore, although a pair of circumferential grooves located on either side of the middle circumferential groove (a pair of outer circumferential grooves) extends in a linear pattern, the present invention is not limited to this aspect, and the outermost circumferential grooves may be zigzag. The tread surface is divided by these circumferential grooves into a pair of middle rib sections 21 and a pair of shoulder rib sections 22.The central rib sections 21 are provided with lateral grooves 31 extending towards the inside in the tire radial direction, and the shoulder rib sections 22 are provided with lateral grooves 32 extending towards the inside in the tire radial direction. The lateral grooves 31 are widened grooves, each having a portion whose groove width in a cross-section perpendicular to the direction of extension is wider than a groove width on the tread surface. On the other hand, the groove widths of the lateral grooves 32 are constant in a cross-section perpendicular to the direction of extension, and thus the lateral grooves 32 are not widened grooves. Although neither end of each lateral groove 31 communicates with any circumferential groove, the present invention is not limited to such an aspect, and at least one end of a lateral groove can communicate with a circumferential groove.Although one end of each lateral groove 32 communicates with a circumferential groove and the other end of each lateral groove 32 extends to a ground-contacting tread end Te, the present invention is not limited to such an aspect. However, from the point of view of drainage performance, a lateral groove whose one end communicates with a circumferential groove and whose other end extends to a ground-contacting tread end Te is preferred.

[0090] The tread section of the tire according to the present embodiment preferably comprises two or more rib sections separated by one or more circumferential grooves, at least one of the rib sections preferably comprises several lateral grooves extending towards the inside in the tire radial direction, and at least one of the lateral grooves is preferably a widened groove.

[0091] Fig.Figure 4 shows a cross-sectional view along the CC line of a lateral groove 31, which is in Fig. Figure 3 shows this cross-section. This cross-section is perpendicular to the direction of extension of the lateral groove 31, which extends towards the inside in the tire radial direction.

[0092] The shapes of the widened portions of the widened grooves are not particularly restricted as long as they improve drainage performance in response to tire wear, thus improving grip performance. For example, the widened portions of the widened lateral grooves 31 of Fig. 3 and Fig. 4. Those whose groove widths widen uniformly along the tire's radial direction from the tread surface to the groove bottoms, that is, those with the widest groove widths at the groove bottoms. Therefore, the more the tire wears, the higher the drainage capacity.

[0093] In Fig.4. Groove walls 42 are recessed on both sides of the lateral groove 31 of a widened groove from a groove edge of the running surface to the groove bottom, and the recession depths are represented by C1 and C2. C1 and C2 each, independently of one another, are preferably 0.05 times or more, more preferably 0.07 times or more, and still more preferably 0.10 times or more of a groove width with a distance between groove edges of the lateral groove (a groove width on the running surface, an opening width) W1, while these values ​​are preferably 0.45 times or less, more preferably 0.40 times or less, and still more preferably 0.35 times or less.

[0094] The groove bottom thickness of the running surface section 1 is preferably 1.0 mm or more and 4.0 mm or less, more preferably 1.5 mm or more and 4.0 mm or less, and even more preferably 2.0 mm or more and 3.5 mm or less. If the groove bottom thickness is within the range described above, heat generation can be suppressed, which is believed to contribute to improved fuel efficiency.

[0095] The elevation ratio R of the tire in relation to the present embodiment, from the perspective of the effects of the present invention, is preferably 0.90 or less, more preferably 0.85 or less, and still more preferably 0.80 or less. Furthermore, from the perspective of abrasion resistance, the elevation ratio R is preferably 0.50 or more, more preferably 0.55 or more, and still more preferably 0.60 or more.

[0096] In Fig.3 is the central circumferential groove in a central area, which is a region of 30% of the tread-ground contact width centered on a tire equator on a tread surface, and has a zigzag shape in the form of a linear groove that is repeatedly curved. The tread section of the tire according to the present embodiment preferably comprises a circumferential groove in the central area, which is a region of 30% of the tread-ground contact width centered on the tire equator on the tread surface.

[0097] In the tread section of the tire according to the present embodiment, if the area comprising 30% of the tread-ground contact width, centered on the tire equator on the tread surface, is defined as a central area, and if areas comprising both outer sides of the central area and located within the tread-ground contact width are defined as a pair of shoulder areas, it is preferred that circumferential grooves are present even in the shoulder areas. If circumferential grooves are present in the shoulder areas, the groove depth of the deepest part of the circumferential groove is preferably 4.0 mm or more, more preferably 4.5 mm or more, still more preferably 5.0 mm or more, still more preferably 5.5 mm or more, and most preferably 6.0 mm or more. The configuration described above can improve drainage performance, and therefore it is believed to contribute to improved wet grip performance.On the other hand, the groove depth of the deepest part of the circumferential groove present in the shoulder areas is preferably 10.0 mm or less, more preferably 9.5 mm or less, still more preferably 9.0 mm or less and particularly preferably 8.5 mm or less.

[0098] The circumferential grooves present in the shoulder areas are different from the circumferential grooves present in the central area mentioned above, and from the circumferential grooves present on the tread surface. That is, the circumferential grooves present in the shoulder areas are circumferential grooves where, even if the groove is present across both the central area and the shoulder areas simultaneously, more than half of the groove is located in the shoulder areas. Furthermore, the groove depth of the deepest part of the circumferential groove present in the shoulder areas is the depth of any circumferential groove with the deepest groove depth, if multiple circumferential grooves are present in the shoulder areas.Furthermore, the groove depth of the deepest part of the circumferential groove present in the shoulder areas refers here to a groove depth of a circumferential groove, if the circumferential groove is present in the shoulder areas, which differs from a groove depth H in mm of the deepest part, which refers to a groove depth of a circumferential groove with the deepest groove depth among all circumferential grooves.

[0099] The tire weight G of the tire according to the present embodiment is preferably 8.0 kg or more, more preferably 8.5 kg or more, even more preferably 9.0 kg or more, and particularly preferably 9.5 kg or more. However, the upper limit of the tire weight G is not normally restricted to 100 kg or less and can be, for example, 80 kg or less, 60 kg or less, 40 kg or less, 20 kg or less, 15 kg or less, or the like. [Rubber composition]

[0100] Any rubber composition forming the tread section of the tire according to the present embodiment (hereinafter referred to as the "rubber compositions according to the present embodiment") comprises a rubber component comprising an isoprene-based rubber and a styrene-butadiene rubber, silicon dioxide, and a dicyclopentadiene-based resin, and can be produced using the raw materials described below. The rubber composition according to the present embodiment is described below. <kautschukkomponente>

[0101] For the rubber composition according to the present embodiment, a diene-based rubber is suitably used as a rubber component. Examples of diene-based rubbers include, for example, isoprene-based rubber, butadiene rubber (BR), styrene-butadiene rubber (SBR), styrene-isoprene rubber (SIR), styrene-isoprene-butadiene rubber (SIBR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), and the like. These diene-based rubbers can be modified rubbers, each treated with a modified group that can interact with a filler such as carbon black, silicon dioxide, and the like, or they can be hydrogenated rubbers in which hydrogenation treatment has been performed on a portion of an unsaturated bond. The diene-based rubber can be used alone, or two or more of them can be used in combination.Furthermore, a diene-based rubber can be a stretched rubber that has been previously stretched with a plasticizer described below.

[0102] The content of a diene-based rubber in a rubber component is preferably 70 wt% or more, more preferably 80 wt% or more, even more preferably 90 wt% or more, and particularly preferably 95 wt% or more. Furthermore, the rubber component can consist of a diene-based rubber.

[0103] The rubber component according to the present embodiment is a rubber component comprising an isoprene-based rubber and a styrene-butadiene rubber, and preferably comprises an isoprene-based rubber, a styrene-butadiene rubber, and a butadiene rubber. The rubber component according to the present embodiment can also be a rubber component consisting of an isoprene-based rubber and a styrene-butadiene rubber, or a rubber component consisting of an isoprene-based rubber, a styrene-butadiene rubber, and a butadiene rubber. (Isoprene-based rubber)

[0104] Isoprene-based rubbers can include those commonly used in the tire industry, such as isoprene rubber (IR), natural rubber, and the like. Examples of natural rubber include not only unrefined natural rubber (NR) but also refined natural rubbers, such as epoxidized natural rubber (ENR), hydrogenated natural rubber (HNR), deproteinized natural rubber (DPNR), ultrapure natural rubber, grafted natural rubber, and the like. These isoprene-based rubbers can be used individually, or two or more can be used in combination.

[0105] The NR is not particularly restricted, and those commonly used in the tire industry can be used, examples of which include SIR20, RSS#3, TSR20 and the like.

[0106] For the purposes of the effects described in the present invention, the content of an isoprene-based rubber in the rubber component is 40% by weight or more, preferably more than 40% by weight, more preferably 45% by weight or more, and even more preferably 50% by weight or more. Furthermore, the content of an isoprene-based rubber is preferably 90% by weight or less, more preferably 80% by weight or less, more preferably 75% by weight or less, and particularly preferably 70% by weight or less. (SBR)

[0107] The SBR is not particularly restricted; examples include an unmodified solution-polymerized SBR (S-SBR), an unmodified emulsion-polymerized SBR (E-SBR), modified SBRs (a modified S-SBR, a modified E-SBR) thereof, and the like. Examples of modified SBR include an SBR modified at its end and / or main chain using a compound possessing a functional group as described below (a modifier), a modified SBR coupled with tin, a silicon compound, etc. (a modified SBR of condensate or with a branched structure, etc.), and the like. Furthermore, hydrogenated versions of these SBRs (hydrogenated SBRs) and the like may also be used. These SBRs may be used individually, or two or more of them may be used in combination.

[0108] The functional group of the modifier is preferably a functional group containing at least one element selected from the group consisting of silicon, nitrogen and oxygen. Examples of such a functional group include, for example, an amino group, an amide group, a silyl group, an alkoxysilyl group, an isocyanate group, an imino group, an imidazole group, a urea group, an ether group, a carbonyl group, an oxycarbonyl group, a mercapto group, a sulfide group, a disulfide group, a sulfonyl group, a sulfinyl group, a thiocarbonyl group, an ammonium group, an imide group, a hydrazo group, an azo group, a diazo group, a carboxyl group, a nitrile group, a pyridyl group, an alkoxy group (preferably an alkoxy group with 1 to 6 carbon atoms), a hydroxyl group, an oxy group, an epoxy group and the like, and an amino group and / or an alkoxysilyl group are preferred.The amino group is preferably an amino group substituted with one or two alkyl groups having 1 to 6 carbon atoms. Specific examples of alkoxysilyl include, for example, trimethoxysilyl, triethoxysilyl, triisopropoxysilyl, dimethoxymethylsilyl, diethoxymethylsilyl, dimethylmethoxysilyl, dimethylethoxysilyl, and the like.

[0109] An oil-enriched or non-oil-enriched SBR can be used as an SBR. The SBRs that can be used in the present embodiment include those commercially available from JSR Corporation, Sumitomo Chemical Co., Ltd., Ube Corporation, Asahi Kasei Corporation, ZS Elastomer Co., Ltd., ARLANXEO, etc.

[0110] For the purposes of the effects described in the present invention, the styrene content S1 of an SBR is 30% by mass or less, preferably 28% by mass or less, more preferably 25% by mass or less, and even more preferably 22% by mass or less. Furthermore, for the purposes of adhesion performance, S1 is preferably 5% by mass or more, more preferably 8% by mass or more, and even more preferably 10% by mass or more.

[0111] The vinyl content of an SBR is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, with the aim of ensuring reactivity with silicon dioxide and abrasion resistance. Furthermore, with regard to elongation at break and abrasion resistance, the vinyl content of the SBR is preferably 45 mol% or less, more preferably 40 mol% or less, and even more preferably 35 mol% or less. In addition, the vinyl content of the SBR is measured in this description using the measurement method described above.

[0112] From the perspective of the effects of the present invention, S1 × R is preferably 11.0 or more, more preferably 12.0 or more, even more preferably 13.0 or more, and particularly preferably 14.0 or more. Furthermore, S1 × R is preferably 20.0 or less, more preferably 18.0 or less, and even more preferably 17.0 or less.

[0113] From the perspective of the effects of the present invention, S1 / G is preferably 1.2 or more, more preferably 1.5 or more, and even more preferably 1.8 or more. Furthermore, S1 / G is preferably 4.0 or less, more preferably 3.5 or less, even more preferably 3.0 or less, and particularly preferably 2.5 or less.

[0114] From the perspective of the effects of the present invention, a glass transition temperature (Tg) of an SBR is preferably -40 °C or lower, more preferably -45 °C or lower, even more preferably -50 °C or lower, and particularly preferably -55 °C or lower. Furthermore, from the perspective of abrasion resistance, it is preferably -90 °C or higher, more preferably -80 °C or higher, and even more preferably -70 °C or higher.

[0115] From the perspective of the effects of the present invention, the weight-average molecular weight (Mw) of an SBR is preferably 100,000 or more, more preferably 200,000 or more, and even more preferably 300,000 or more. Furthermore, from the perspective of crosslinking uniformity, the weight-average molecular weight is preferably 2,000,000 or less, more preferably 1,800,000 or less, and even more preferably 1,500,000 or less. The weight-average molecular weight of the SBR is also measured by the measurement method described above.

[0116] For the purposes of the effects of the present invention, the content of SBR in the rubber component is preferably 10 wt% or more, more preferably 20 wt% or more, even more preferably 25 wt% or more, even more preferably 30 wt% or more, and particularly preferably 35 wt% or more. Furthermore, the content of SBR in the rubber component is preferably 60 wt% or less, more preferably 55 wt% or less, even more preferably 50 wt% or less, and particularly preferably 45 wt% or less. (BR)

[0117] The type of rubber (BR) is not particularly restricted, and those commonly used in the tire industry can be employed, such as a BR with a cis content of less than 50 mol% (a cis-poor BR), a BR with a cis content of 90 mol% or more (a cis-rich BR), a rare-earth-based butadiene rubber synthesized using a rare-earth-based catalyst (a rare-earth-based BR), a BR containing a syndiotactic polybutadiene crystal (an SPB-containing BR), a modified BR (a cis-rich modified BR, a cis-poor modified BR), and the like. These BRs can be used individually, or two or more of them can be used in combination.

[0118] For example, cis-rich rubbers (BRs) from Zeon Corporation, UBE Corporation, JSR Corporation, etc., can be used. Including a cis-rich BR in the rubber composition can improve low-temperature properties and abrasion resistance. The cis content of a cis-rich BR is preferably greater than 95 mol%, more preferably greater than 96 mol%, and even more preferably greater than 97 mol%. Furthermore, the cis content of a BR is measured using the measurement method described above.

[0119] The rare-earth-based BR is synthesized using a rare-earth-element-based catalyst and has a vinyl content preferably less than 1.8 mol%, more preferably less than 1.6 mol%, and still more preferably less than 1.5 mol%, and a cis content preferably more than 95 mol%, more preferably more than 96 mol%, and still more preferably more than 97 mol%. For example, the rare-earth-based BR can be one of those commercially available from LANXESS, etc.

[0120] Examples of BR containing SPB include those in which a 1,2-syndiotactic polybutadiene crystal is chemically bonded and dispersed with BR, but not those in which the crystal is simply dispersed in the BR. BRs commercially available from UBE Corporation, etc., can be considered as such SPB-containing BRs.

[0121] Examples of modified BR include BRs modified with the same functional group as described above for SBR and the like, and a modified butadiene rubber (modified BR) which is modified at its end and / or main chain with a functional group containing at least one element selected from the group consisting of silicon, nitrogen and oxygen, may also be used appropriately.

[0122] Examples of other modified BRs include those obtained by adding a tin compound after polymerizing 1,3-butadiene via a lithium initiator, with the end of the modified BR molecule further bonded by a tin-carbon bond (tin-modified BRs), and the like. Furthermore, the modified BR can be either non-hydrogenated or hydrogenated.

[0123] The weight-average molecular weight (Mw) of BR is preferably greater than 300,000, more preferably greater than 350,000, and even more preferably greater than 400,000, with regard to abrasion resistance. Furthermore, with regard to crosslink uniformity, etc., it is preferably less than 2,000,000, more preferably less than 1,000,000, and even more preferably less than 500,000. The Mw is also calculated using the measurement method described above.

[0124] The content of BR in the rubber component is not particularly restricted and is preferably 1 wt% or more, more preferably 5 wt% or more, even more preferably 10 wt% or more, and particularly preferably 15 wt% or more. Furthermore, the content of BR in the rubber component is preferably 50 wt% or less, more preferably 40 wt% or less, even more preferably 30 wt% or less, and particularly preferably 25 wt% or less.

[0125] From the perspective of the effects of the present invention, the total amount of styrene S2 in the rubber component is preferably 15 wt% or less, more preferably 12 wt% or less, and even more preferably 10 wt% or less. Furthermore, S2 is preferably 3 wt% or more, more preferably 5 wt% or more, and even more preferably 7 wt% or more. (Other rubber components)

[0126] The rubber component may comprise a rubber component other than diene-based rubbers (non-diene-based rubber), as long as it does not affect the effects of the present invention. A non-diene-based rubber may be a rubber component commonly used in the tire industry, examples of which include, for instance, butyl-based rubber, ethylene propylene rubber, polynorbornene rubber, silicone rubber, polyethylene chloride rubber, fluororubber (FKM), acrylic rubber (ACM), hydrin rubber, and the like. These non-diene-based rubbers may be used alone, or two or more of them may be used in combination. Furthermore, in addition to the rubber components described above, it may or may not include a known thermoplastic elastomer. (Rubber component synthesized from recycled / biomass-derived raw material)

[0127] A monomer that is a structural unit of a synthetic rubber, such as IR, BR, SBR, and the like, can be derived from underground resources, such as petroleum, natural gas, and the like, or recycled from a rubber product, such as a tire, and the like, or from a non-rubber product, such as polystyrene, and the like. Examples of recycled monomers include, but are not limited to, recycled polyisoprene, recycled butadiene, and aromatic vinyl compounds. Examples of butadiene, as described above, include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds include, but are not limited to, styrene and the like.Among these, recycled polyisoprene (recycled isoprene), recycled butadiene (recycled butadiene) and recycled styrene (recycled styrene) are preferably used as raw materials.

[0128] A process for producing a recycled monomer is not particularly restricted; examples include, for instance, the synthesis of a recycled monomer from recycled naphtha obtained by decomposing a rubber product, such as a tire. Furthermore, a process for producing recycled naphtha is not particularly restricted and can be carried out, for example, by decomposing a rubber product, such as a tire, under high temperature and high pressure, by decomposing it using microwaves, or by extracting it after mechanical pulverization.

[0129] Furthermore, a monomer that is a structural unit of a synthetic rubber, such as IR, BR, SBR, and the like, can be one derived from biomass. In this description, "biomass" refers to a material derived from natural resources, such as plants and the like. Examples of biomass include, but are not limited to, agricultural, forestry, and fishery products; sugar; wood waste; plant residues after the capture of a useful component; plant-derived ethanol; biomass naphtha.

[0130] Examples of biomass-derived monomers (biomass monomers) include biomass-derived butadiene, biomass-derived aromatic vinyl compounds, and the like, but they are not particularly limited. Examples of butadiene, as described above, include 1,2-butadiene and 1,3-butadiene. Examples of aromatic vinyl compounds, as described above, include, but are not particularly limited, styrene and the like. Furthermore, a process for producing a biomass monomer is not particularly limited; examples include, for instance, a process by biological and / or chemical and / or physical conversion of an animal or plant, and the like.Microbial fermentation is representative of biological conversion, and examples of chemical and physical conversion include a process that uses a catalyst, a process that uses high heat, a process that uses high pressure, a process that uses an electromagnetic wave, a process that uses a critical fluid, combinations thereof, and the like.

[0131] Examples of a polymer synthesized from a biomass monomer component (biomass polymer) include a polybutadiene rubber synthesized from biomass-derived butadiene, an aromatic vinyl / butadiene copolymer synthesized from biomass-derived butadiene and / or a biomass-derived aromatic vinyl compound, and the like, but they are not particularly limited. Examples of aromatic vinyl butadiene copolymers include, for example, a styrene-butadiene rubber synthesized from biomass-derived butadiene and / or biomass-derived styrene, and the like.

[0132] Whether a polymer's raw material is derived from biomass or not can be determined by pMC (percent modern carbon), measured according to ASTM D6866-10.

[0133] Here, "pMC" means a ratio of 14 C concentration of a sample to 14 The carbon concentration of a modern standard reference carbon (modern standard reference) is a value used as an index indicating the biomass ratio of a compound. The meaning of this value is mentioned below.

[0134] In 1 mol of carbon atoms (approx. 6.02 × 10 23 There are approximately 6.02 × 10 11 14 C, which are about one trillionth the number of normal carbon atoms. A half-life of 14 C is 5730 years, and 14 Carbon decreases regularly. Therefore, in fossil fuels such as coal, oil, natural gas, and the like, where it is assumed that 226,000 years or more have passed since carbon dioxide was absorbed into the atmosphere by plants to be fixed, all the carbon dioxide decomposes. 14 Carbon elements, which were present at the beginning of the fixation. Therefore, fossil fuels, such as coal, oil, natural gas and the like, do not contain any carbon in the current 21st century. 14 Carbon element. Accordingly, the chemical substances produced using these fossil fuels as raw materials also contain no carbon. 14 C-element.

[0135] On the other hand 14 C is constantly produced by cosmic rays that cause nuclear reactions in the atmosphere. Thus, a decrease of 14 C due to radioactive decay and the production of 14 C is balanced due to nuclear reactions and is the amount of 14 The temperature C in the Earth's atmospheric environment is constant. Therefore, the 14 Carbon concentration of substances derived from biomass resources that have circulated in the current environment to a value of approximately 1 × 10 -12 Molar percentages, based on total carbon atoms, as described above. Accordingly, by using the difference between these values, a biomass ratio in a given compound can be calculated.

[0136] This 14 C is generally measured as follows. Using accelerator mass spectrometry based on a tandem accelerator, a 13 C concentration ( 13 C / 12 C) and a 14 C concentration ( 14 C / 12 C) measured. During the measurements, a 14 Carbon concentration in a circulating carbon in nature from 1950 as the modern standard reference for the 14 C concentration is used. A standard oxalic acid body provided by the National Institute of Standards and Technology (NIST) is used as a specific reference material. A specific radioactivity of carbon in this oxalic acid (radioactivity intensity of 14 C per gram of carbon) is sorted for each carbon isotope. 13 C is corrected to a constant value, and a value corrected for attenuation correction from 1950 to the measurement date is considered a standard. 14 A carbon concentration value (100%) is used. A ratio of this value to an actual measured value for a sample is called a pMC value.

[0137] Thus, when a rubber is produced from a material derived 100% from biomass, the 14 The carbon concentration typically has a value of approximately 110 pMC; currently, under normal conditions, it often does not reach 100, although there are regional differences and the like. On the other hand, it shows when this 14 When the carbon concentration of a chemical substance derived from a fossil fuel, such as petroleum, is measured, it will be approximately 0 pMC (for example, 0.3 pMC). This value corresponds to a biomass ratio of 0%, as mentioned above.

[0138] Based on the above, it is suitable in terms of environmental protection to use a material, such as rubber, that has a high pMC value, i.e. a material, such as rubber, that has a high biomass ratio, for a rubber composition. [Filler]

[0139] The rubber composition according to the present embodiment comprises silicon dioxide as a filler and further preferably comprises silicon dioxide and carbon black. In addition, the filler can be a filler consisting of carbon black and silicon dioxide. (Silicon dioxide)

[0140] Silicon dioxide is not particularly restricted, and those commonly used in the tire industry can be employed, such as silicon dioxide produced by a dry process (anhydrous silicon dioxide), silicon dioxide produced by a wet process (hydrous silicon dioxide), and the like. The source of silicon dioxide is not particularly restricted and can be, for example, a raw material derived from a mineral, such as quartz, or a raw material derived from a biological substance, such as rice husks (e.g., silicon dioxide from a biomass material, such as rice husks, and the like), or silicon dioxide recycled from a silicon dioxide-containing product. Among these, hydrous silicon dioxide produced by a wet process is preferred because it contains many silanol groups.This silicon dioxide can be used alone, or two or more of them can be used in combination.

[0141] Silicon dioxide from a biomass material can be obtained, for example, by burning rice husks to obtain rice husk ash, extracting silicate from the rice husk ash using a sodium hydroxide solution, producing silicon dioxide by reacting the silicate with sulfuric acid in the same way as for conventional wet silicon dioxide, and filtering, washing with water, drying, and pulverizing the silicon dioxide precipitates.

[0142] Silicon dioxide recycled from a product containing silicon dioxide can, for example, be recovered from an electronic component, such as a semiconductor, a tire, a product containing silicon dioxide, such as a desiccant, a filter material, such as diatomaceous earth, and the like. Furthermore, the recovery method is not particularly restricted; examples include pyrolysis, decomposition by electromagnetic waves, and the like. Silicon dioxide recovered from an electronic component, such as a semiconductor, or from a tire is preferred.

[0143] When silicon dioxide crystallizes, it is insoluble in water, and silicic acid, a component of it, cannot be used. Crystallization of silicon dioxide in rice hull ash can be suppressed by controlling the firing temperature and duration (see JP 2009-2594 A, Akita Prefectural University Web Journal B / 2019, vol. 6, pp. 216-222 etc.).

[0144] Amorphous silicon dioxide extracted from rice husks can be used, including those commercially available from Wilmar, etc.

[0145] A specific nitrogen adsorption surface area (N2SA) of silicon dioxide is preferably greater than 110 m² from the perspective of enhancement properties. 2 / g, preferably larger than 130 m 2 / g, preferably larger than 150 m 2 / g and especially preferably larger than 170 m 2 / g. Furthermore, from the perspective of heat generation and processability, it is preferably less than 220 m. 2 / g, preferably less than 200 m 2 / g and even more preferably less than 180 m 2 / g or less. Furthermore, the N2SA of silicon dioxide is measured using the measurement method described above.

[0146] For the purposes of this application, the average primary particle size of silicon dioxide is preferably greater than 10 nm, more preferably greater than 12 nm, and even more preferably greater than 14 nm. Furthermore, the average primary particle size is preferably less than 20 nm, more preferably 18 nm or less, and even more preferably 17 nm or less. The average primary particle size of silicon dioxide is also measured using the measurement method described above.

[0147] For the purposes of the effects of the present invention, the silicon dioxide content based on 100 parts by mass of the rubber component is 30 parts by mass or more, preferably more than 30 parts by mass, further preferably 35 parts by mass or more, even more preferably 40 parts by mass or more, even more preferably 45 parts by mass or more, even more preferably 50 parts by mass or more, even more preferably 55 parts by mass or more, and particularly preferably 60 parts by mass or more. Furthermore, for compatibility with an isoprene-based rubber, the content is preferably 120 parts by mass or less, more preferably 110 parts by mass or less, even more preferably 100 parts by mass or less, and particularly preferably 90 parts by mass or less.

[0148] From the perspective of the effects of the present invention, the silicon dioxide content in the filler is preferably 55% by mass or more, more preferably 65% ​​by mass or more, even more preferably 75% by mass or more, and particularly preferably 80% by mass or more. Furthermore, from the perspective of abrasion resistance, it is preferably 95% by mass or less, more preferably 92% by mass or less, and even more preferably 90% by mass or less. <Ruß>

[0149] Examples of carbon black include, but are not limited to, N134, N110, N220, N234, N219, N339, N330, N326, N351, N550, N762, and the like. A raw material for carbon black can be a biomass material, such as lignin, vegetable oil, and the like, or it can be pyrolysis oil obtained by pyrolyzing a used tire. Furthermore, a process for producing carbon black can be a combustion process, such as a furnace process, a hydrothermal carbonization (HTC) process, or a thermal carbon black process using methane pyrolysis, and the like. Products from ASAHI CARBON CO., LTD., Cabot Japan KK, TOKAI CARBON CO., LTD., Mitsubishi Chemical Corporation, Lion Corporation, NIPPON STEEL Carbon Co., Ltd., Columbia Carbon Corporation, etc., can be used as commercially available products.These soots can be used alone, or two or more of them can be used in combination.

[0150] Furthermore, as a carbon black other than the carbon black described above, from the point of view of a life cycle assessment etc., carbon black made from a biomass material, such as lignin and the like, or recovered carbon black refined by pyrolysis of a product containing carbon black, such as a tire and the like, can be used.

[0151] In this description, the term "recovered carbon black" refers to carbon black obtained by pulverizing a product such as a used tire containing carbon black and the like, and burning the pulverized product. When the product is subjected to oxidative combustion by heating in air using a thermal weight measurement method in accordance with JIS K 6226-2:2003, the ratio of mass to ash (ash content), which is a non-combustible component, is 13% by mass or more. That is, the ratio of mass (amount of carbon) to weight loss due to the oxidative combustion of the recovered carbon black is 87% by mass or less. The recovered carbon black can be expressed as rCB.

[0152] Recovered carbon black can be obtained from a pyrolysis process of a used pneumatic tire. EP 3427975 A, for example, refers to “Rubber Chemistry and Technology”, Vol. 85, No. 3, pp. 408-449 (2012), in particular pages 438, 440 and 442, and describes how recovered carbon black can be obtained by pyrolysis of an organic material at 550 °C to 800 °C under an oxygen-free environment or by vacuum pyrolysis at a relatively low temperature (

[0027] ). As described in

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

[0153] The recovered carbon black can be one lacking a functional group on its surface, or it can be one treated to contain a functional group on its surface. This treatment of the recovered carbon black, resulting in a functional group on its surface, can be carried out by a conventional method. For example, in EP 3173251 A, carbon black obtained from a pyrolysis process is treated with potassium permanganate under acidic conditions, yielding carbon black containing a hydroxyl group and / or a carboxyl group on its surface. Furthermore, in JP 6856781 B, carbon black obtained from a pyrolysis process is treated with an amino acid compound containing at least one thiol group or disulfide group, yielding carbon black with an activated surface.Examples of recovered carbon black according to the present embodiment also include carbon black that has been treated to contain a functional group on its surface.

[0154] The recovered carbon black can be that which is commercially available from Strebl Green Carbon Pte Ltd., LDCarbon Co., Ltd. etc.

[0155] A specific nitrogen adsorption surface area (N2SA) of carbon black is preferably greater than 70 m² from the perspective of its amplifying properties. 2 / g, preferably larger than 100 m 2 / g, preferably larger than 120 m 2 / g and especially preferably larger than 140 m 2 / g. Furthermore, from the perspective of heat generation and processability, it is preferably less than 250 m. 2 / g, preferably less than 220 m 2 / g and even more preferably less than 190 m 2 / g. In addition, the N2SA of the soot is measured using the measurement method described above.

[0156] The average primary particle size of carbon black is preferably smaller than 32 nm, more preferably smaller than 28 nm, still more preferably smaller than 24 nm, still more preferably smaller than 20 nm, and particularly preferably smaller than 18 nm. Furthermore, the average primary particle size is preferably larger than 8 nm, more preferably larger than 10 nm, still more preferably larger than 12 nm, and particularly preferably larger than 14 nm. The average primary particle size of carbon black is also measured using the measurement method described above.

[0157] From the perspective of abrasion resistance, the carbon black content based on 100 parts by mass of the rubber component is preferably 1 part by mass or more, further preferably 3 parts by mass or more, and even more preferably 5 parts by mass or more. Furthermore, from the perspective of heat suppression, the content is preferably 50 parts by mass or less, further preferably 45 parts by mass or less, even more preferably 40 parts by mass or less, even more preferably 35 parts by mass or less, even more preferably 25 parts by mass or less, even more preferably 15 parts by mass or less, and particularly preferably 10 parts by mass or less. <Andere Füllstoffe>

[0158] The filler may consist of a filler other than silicon dioxide and carbon black. The other filler is not particularly restricted, and those conventionally and commonly used in the tire industry can be considered, such as aluminum hydroxide, calcium carbonate, alumina, clay, talc, and the like.

[0159] The total filler content, based on 100 parts by mass of the rubber component, is preferably 40 parts by mass or more, further preferably 45 parts by mass or more, even more preferably 50 parts by mass or more, and particularly preferably 55 parts by mass or more. Furthermore, the content is preferably 140 parts by mass or less, further preferably 120 parts by mass or less, even more preferably 100 parts by mass or less, and particularly preferably 90 parts by mass or less. <silankupplungsmittel>

[0160] The silicon dioxide is preferably used in combination with a silane coupling agent. The silane coupling agent is not particularly restricted, and examples include, for instance, a sulfide-based silane coupling agent, such as bis(3-triethoxysilylpropyl)disulfide, bis(3-triethoxysilylpropyl)tetrasulfide, and the like; a mercapto-based silane coupling agent, such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 2-mercaptoethyltrimethoxysilane, 2-mercaptoethyltriethoxysilane, and the like; a vinyl-based silane coupling agent, such as vinyltriethoxysilane, vinyltrimethoxysilane, and the like; an amino-based silane coupling agent, such as 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, and the like.A glycidoxy-based silane coupling agent, such as γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and the like; a nitro-based silane coupling agent, such as 3-nitropropyltrimethoxysilane, 3-nitropropyltriethoxysilane, and the like; a chlorine-based silane coupling agent, such as 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, and the like; and the like. A sulfide-based and / or a mercapto-based silane coupling agent is preferably combined in the rubber composition. For example, the silane coupling agents used may be those commercially available from Evonik Industries AG, Momentive Performance Materials, etc. These silane coupling agents may be used alone, or two or more may be used in combination.

[0161] The content of a silane coupling agent based on 100 parts by mass of the rubber component (a total amount of all silane coupling agents when used in combination) is, from the perspective of enhancing the dispersibility of silicon dioxide, preferably more than 3.0 parts by mass, further preferably more than 5.0 parts by mass, and even more preferably more than 6.0 parts by mass. Furthermore, from the perspective of preventing deterioration of abrasion resistance, it is preferably less than 15 parts by mass, further preferably less than 10 parts by mass, and even more preferably less than 8.0 parts by mass. [Other fasteners]

[0162] The rubber composition according to the present embodiment may, in addition to the rubber component and the filler, suitably comprise bonding agents that are conventionally and commonly used in the tire industry, for example a plasticizer, a vulcanized rubber particle, processing aids, wax, stearic acid, zinc oxide, an antioxidant, a vulcanizing agent, a vulcanization accelerator and the like. <weichmacher>

[0163] A plasticizer is a material that imparts plasticity to a rubber component and is a concept encompassing both plasticizers that are liquid at 25°C and those that are solid at room temperature (25°C). Examples of plasticizers include resin components, oils, liquid rubber, ester-based plasticizers, and the like. These plasticizers can be derived from mineral resources such as petroleum, natural gas, and the like; derived from biomass; or derived from naphtha recycled from a rubber or non-rubber product. Additionally, low-molecular-weight hydrocarbon components obtained by pyrolyzing and extracting used tires or products containing various components can be used as plasticizers.These plasticizers can be used alone, or two or more of them can be used in combination. (resin component)

[0164] The rubber composition according to the present embodiment can comprise a dicyclopentadiene-based resin as one resin component or can be used in combination with another resin component. The dicyclopentadiene-based resin is preferably a resin comprising dicyclopentadiene, styrene, and indene as monomer components. <<Harz auf Dicyclopentadien-Basis> >

[0165] A “dicyclopentadiene-based resin” means a resin that comprises cyclopentadiene (CPD) or dicyclopentadiene (DCPD) as a monomer component and may be one that undergoes hydrogenation or modification. Examples of dicyclopentadiene-based resins include, for example, a DCPD / C9 resin comprising dicyclopentadiene and a C9 fraction, described below, as a monomer component (the DCPD / C9 resin may be one that undergoes hydrogenation or modification), and the like. A DCPD / C9 resin comprising dicyclopentadiene and styrene as a monomer component is preferred, and a DCPD / C9 resin comprising dicyclopentadiene, styrene, and indene as a monomer component is further preferred. Examples of resins suitable for use as dicyclopentadiene-based resins include those produced by Exxon Mobil Chemical Corporation, ENEOS Corporation, Zeon Corporation, and Maruzen Petrochemical Co., Ltd. etc. are commercially available.These dicyclopentadiene-based resins can be used alone, or two or more of them can be used in combination.

[0166] The other resin component is not particularly restricted, and any resin component commonly used in the tire industry can be used. Examples of resin components include adhesive resins such as aromatic vinyl-based resin, C9-based resin, C5-based resin, C5 / C9-based resin, coumaron-based resin, indene-based resin, terpene-based resin, rosin-based resin, phenol-based resin, and the like. These resin components can be used alone, or two or more of them can be used in combination. <<Harz auf aromatischer Vinyl-Basis> >

[0167] An "aromatic vinyl-based resin" means a resin that incorporates an aromatic vinyl compound, such as styrene, α-methylstyrene, vinyltoluene, p-chlorostyrene, and the like, as the monomer component with the highest concentration in the resin. This resin may be one that has undergone hydrogenation or modification. A homopolymer of α-methylstyrene or styrene, or a copolymer of α-methylstyrene and styrene, is preferred as the aromatic vinyl-based resin because it is economical, easy to process, and offers excellent heat generation. The copolymer of α-methylstyrene and styrene is further preferred. Examples of aromatic vinyl-based resins that can be used include those commercially available from Kraton Corporation, Eastman Chemical Company, Mitsui Chemicals, Inc., etc. These aromatic vinyl-based resins can be used individually, or two or more can be used in combination. <<Harz auf C9-Basis> >

[0168] A "C9-based resin" is a resin obtained by polymerizing C9 fractions. This can be a resin obtained by homopolymerizing C9 fractions, or a copolymer obtained by copolymerizing C9 fractions with another component. For example, a resin obtained by copolymerizing dicyclopentadiene (DCPD) and C9 fractions is called a "DCPD / C9 resin." Furthermore, C9-based resins can be those that undergo hydrogenation or modification. Examples of C9 fractions include petroleum fractions with 8 to 10 carbon atoms, such as vinyltoluene, alkylstyrene, coumaron, indene, methylindene, dicyclopentadiene, and the like. These C9-based resins can be used alone, or two or more can be used in combination. <<Harz auf C5-Basis> >

[0169] A "C5-based resin" is a resin obtained by polymerizing C5 fractions, which may include those that have undergone hydrogenation or modification. Examples of C5 fractions include petroleum fractions with 4 to 5 carbon atoms, such as cyclopentadiene, isoprene, pentane, isopentane, neopentane, pentene, pentadiene, and the like. These C5-based resins can be used individually, or two or more of them can be used in combination. <<Harz auf C5 / C9-Basis> >

[0170] A "C5 / C9-based resin" is a resin obtained by copolymerizing the C5 and C9 fractions described above, and may include those that undergo hydrogenation or modification. Examples of C5 / C9-based petroleum resins include those commercially available from Tosoh Corporation, Zibo Luhua Hongjin New Material Group Co., Ltd. These C5 / C9-based resins can be used individually, or two or more can be used in combination. <<Harz auf Cumaron-Basis> >

[0171] A "coumaron-based resin" means a resin that contains coumaron as a monomer component and may be one that undergoes hydrogenation or modification. Examples of coumaron-based resins include, for instance, a coumaron-indene resin, which contains coumaron and indene as monomer components; a coumaron-indene-styrene resin, which contains coumaron, indene, and styrene as monomer components; and the like. These coumaron-based resins can be used alone, or two or more of them can be used in combination. <<Harz auf Inden-Basis> >

[0172] An "indene-based resin" means a resin that includes indene as a monomer component and may be one that undergoes hydrogenation or modification. Examples of indene-based resins include, for instance, a coumaron-indene resin, which includes coumaron and indene as a monomer component; a coumaron-indene-styrene resin, which includes coumaron, indene, and styrene as a monomer component; and the like. These indene-based resins can be used alone, or two or more of them can be used in combination. <<Harz auf Terpen-Basis> >

[0173] A "terpene-based resin" means a resin that, as a monomer component with the highest concentration in the resin, comprises a terpene compound, such as α-pinene, β-pinene, limonene, dipentene, and the like, and may be one that has undergone hydrogenation or modification. Specific examples of terpene-based resins include, for example, a polyterpene resin comprising only one or more of the terpene compounds described above as a monomer component; an aromatically modified terpene resin comprising a terpene compound described above and an aromatic compound as a monomer component; a terpenophenolic resin comprising a terpene compound described above and a phenol-based compound as a monomer component; and the like.Examples of aromatic compounds that become monomeric components of the aromatically modified terpene resin include styrene, α-methylstyrene, vinyltoluene, divinyltoluene, and the like. Examples of phenol-based compounds that become monomeric components of the terpene-phenol resin include phenol, bisphenol A, cresol, xylenol, and the like. These terpene-based resins can be used individually, or two or more of them can be used in combination. <<Harz auf Kolophonium-Basis> >

[0174] A “rosin-based resin” means a resin comprising a rosin acid compound, such as abietic acid, neoabietic acid, palustric acid, isopimaric acid, and the like, and may be one that has undergone hydrogenation or modification. Examples of rosin-based resins include, but are not limited to: natural resin rosin; and a rosin-modified resin obtained by modifying the rosin through hydrogenation, disproportionation, dimerization, esterification, or the like. These rosin-based resins may be used alone, or two or more of them may be used in combination. <<Harz auf Phenol-Basis> >

[0175] A "phenol-based resin" is a resin that contains a phenol compound, such as phenol, cresol, and the like, as its highest monomer component. Examples of phenol-based resins include, but are not limited to, phenol-formaldehyde resins, alkylphenol-formaldehyde resins, alkylphenol-acetylene resins, oil-modified phenol-formaldehyde resins, and the like. These phenol-based resins can be used individually, or two or more can be used in combination. < <erweichungspunkt>>

[0176] From the perspective of wet adhesion performance, the softening point of a resin component is preferably 80 °C or higher, more preferably 90 °C or higher, and even more preferably 100 °C or higher. Furthermore, from the perspective of processability and improved dispersibility of a filler in a rubber component, it is preferably 150 °C or lower, more preferably 140 °C or lower, and even more preferably 130 °C or lower. The softening point of the resin is also measured using the measurement method described above. < <gehalt>>

[0177] The total content of a resin component based on 100 parts by mass of the rubber component is preferably 5 parts by mass or more, further preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, even more preferably 20 parts by mass or more, and particularly preferably 25 parts by mass or more. On the other hand, from the point of view of suppressing heat generation, the content is preferably 60 parts by mass or less, further preferably 50 parts by mass or less, and even more preferably 45 parts by mass or less.

[0178] The content of a dicyclopentadiene-based resin, based on 100 parts by mass of the rubber component, is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, even more preferably 20 parts by mass or more, and particularly preferably 25 parts by mass or more. On the other hand, from the perspective of heat generation suppression, the content is preferably 60 parts by mass or less, more preferably 50 parts by mass or less, and even more preferably 45 parts by mass or less. (Oil)

[0179] Examples of oil include mineral oils, vegetable oils, animal oils, and the like. Furthermore, from a life cycle assessment perspective, one can be used that is obtained by refining used oil after its use in a rubber mixer or engine, or used cooking oil from a restaurant.

[0180] In this patent specification, "mineral oil" refers to oil derived from mineral resources such as petroleum, natural gas, and the like. Examples of mineral oil include paraffinic oils (mineral oils), naphthenic oils, aromatic oils, and the like. Specific examples of mineral oils include, for example, Mild Extracted Solvated (MES), Distillate Aromatic Extract (DAE), Treated Distillate Aromatic Extract (TDAE), Treated Residual Aromatic Extract (TRAE), Residual Aromatic Extract (RAE), and the like. Furthermore, as an environmental measure, oils that each have a low content of a polycyclic aromatic compound (PCA) may also be used. Examples of oils that each have a low content of a PCA include MES, TDAE, heavy naphthenic oil, and the like.

[0181] In the present patent specification, examples of vegetable oil include, for example, linseed oil, rapeseed oil, safflower oil, soybean oil, corn oil, cottonseed oil, rice bran oil, tall oil, sesame oil, perilla oil, castor oil, tung oil, pine oil, pine tar oil, sunflower oil, coconut oil, palm oil, palm kernel oil, olive oil, camellia oil, jojoba oil, macadamia nut oil, peanut oil, grapeseed oil, Japan wax, and the like. Furthermore, examples of vegetable oil also include refined oil obtained by refining the oil described above (edible oil, etc.).), a transesterified oil obtained by transesterifying the oil described above, a hydrogenated oil obtained by hydrogenating the oil described above, a thermally polymerized oil obtained by thermally polymerizing the oil described above, an oxidized polymerized oil obtained by oxidizing the oils described above, a used cooking oil obtained by restoring what was previously used as an edible oil, etc., and the like. Furthermore, the vegetable oil may be liquid or solid at room temperature (25°C). These vegetable oils may be used individually, or two or more of them may be used in combination.

[0182] The vegetable oil according to the present embodiment preferably comprises acylglycerol and further preferably comprises triacylglycerol. In this description, acylglycerol also refers to a compound in which a hydroxyl group of glycerol and a fatty acid are ester-bound. Acylglycerol is not particularly restricted and can be any of the following: 1-monoacylglycerol, 2-monoacylglycerol, 1,2-diacylglycerol, 1,3-diacylglycerol, and triacylglycerol. Furthermore, the acylglycerol can be a monomer, a dimer, or a multimer that is a trimer or higher. Acylglycerol that is a dimer or higher can also be obtained by thermal polymerization, oxidative polymerization, or the like. Finally, acylglycerol can be liquid or solid at room temperature (25 °C).

[0183] One method of verifying whether the rubber composition includes the acylglycerol described above can be carried out, for example, by 1 H-NMR measurements can be performed below, but are not particularly limited to this. In particular, a rubber composition in which triacylglycerol is bonded is immersed in a heavy chloroform at room temperature (25 °C) for 24 hours and removed to 1 When measuring ¹H NMR at room temperature, and when a signal from tetramethylsilane (TMS) is set to 0.00 ppm, signals near 5.26 ppm, near 4.28 ppm, and near 4.15 ppm are observed, with the signals being thought to be derived from hydrogen atoms bonded to carbon atoms adjacent to oxygen atoms of an ester group. Furthermore, "near" in this paragraph refers to a range of ±0.10 ppm.

[0184] The fatty acid described above is not particularly restricted and can be either an unsaturated or a saturated fatty acid. Examples of unsaturated fatty acids include monounsaturated fatty acids, such as oleic acid, and the like; and polyunsaturated fatty acids, such as linoleic acid, linolenic acid, and the like. Furthermore, examples of saturated fatty acids include butyric acid, lauric acid, and the like.

[0185] The desired fatty acid, as described above, is one with few double bonds, meaning a saturated or monounsaturated fatty acid, and oleic acid is preferred. A vegetable oil containing such a fatty acid could be, for example, a vegetable oil containing a saturated or monounsaturated fatty acid, or a vegetable oil modified by transesterification or similar processes. Furthermore, to produce a vegetable oil containing such a fatty acid, a plant can be improved through selective breeding, gene combination, or similar methods.

[0186] Suitable vegetable oils include, for example, those commercially available from Idemitsu Kosan Co., Ltd., Sankyo Yuka Kogyo KK, ENEOS Corporation, Olisoy, H&R Group, HOKOKU Corporation, Fuji Kosan Co., Ltd., The Nisshin Oillio Group, etc.

[0187] Examples of animal oils include fish oils, beef tallow, oleyl alcohol derived from it, and the like.

[0188] When combined, the oil content, based on 100 parts by mass of the rubber component, is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and even more preferably 7 parts by mass or more, from the perspective of the effects of the present invention. Furthermore, the content is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and even more preferably 30 parts by mass or less. (Liquid rubber)

[0189] Liquid rubber is not particularly restricted as long as it is a polymer in a liquid state at normal temperature (25 °C). Examples include liquid butadiene rubber (liquid BR), liquid styrene-butadiene rubber (liquid SBR), liquid isoprene rubber (liquid IR), liquid styrene-isoprene rubber (liquid SIR), liquid farnesene rubber, and the like. These liquid rubbers can be used individually, or two or more of them can be used in combination. (Ester-based plasticizers)

[0190] Examples of ester-based plasticizers include dibutyl adipate (DBA), diisobutyl adipate (DIBA), dioctyl adipate (DOA), di(2-ethylhexyl) azelate (DOZ), dibutyl sebacate (DBS), diisononyl adipate (DINA), diethyl phthalate (DEP), dioctyl phthalate (DOP), diundecyl phthalate (DUP), dibutyl phthalate (DBP), dioctyl sebacate (DOS), tributyl phosphate (TBP), trioctyl phosphate (TOP), triethyl phosphate (TEP), trimethyl phosphate (TMP), thymidine triphosphate (TTP), tricresyl phosphate (TCP), trixylenyl phosphate (TXP), and the like. These ester-based plasticizers can be used alone, or two or more of them can be used in combination.

[0191] The content of a plasticizer based on 100 parts by mass of the rubber component (a total amount of all of several plasticizers when used in combination) is, from the perspective of wet adhesion performance, preferably 20 parts by mass or more, further preferably 25 parts by mass or more, even more preferably 30 parts by mass or more, and particularly preferably more than 35 parts by mass. Furthermore, from the perspective of processability, it is preferably 100 parts by mass or less, further preferably 90 parts by mass or less, even more preferably 80 parts by mass or less, and particularly preferably 70 parts by mass or less. <<vulkanisierte Kautschukpartikel> >

[0192] Vulcanized rubber particles are particles made from vulcanized rubber. Specifically, rubber powder as specified in JIS K 6316:2017, and similar materials, can be used. Recycled rubber powder produced from a powdered end-of-life tire or similar material is preferred from an environmental and cost perspective. They can be used individually, or two or more can be used in combination.

[0193] The vulcanized rubber particle is not particularly restricted and can be either unmodified or modified vulcanized rubber. Commercially available vulcanized rubber products, such as those manufactured by Lehigh Technologies, Muraoka Rubber Reclaiming Co., Ltd., etc., can be used.

[0194] The content of the vulcanized rubber particle, when bonded, based on 100 parts by mass of the rubber component, can be appropriately adjusted, for example, within a range of more than 1 part by mass and less than 80 parts by mass. < <verarbeitungshilfsmittel>>

[0195] Examples of processing aids include, for example, a fatty acid metal salt, a fatty acid amide, an amide ester, a silicon dioxide surfactant, a fatty acid ester, a mixture of a fatty acid metal salt and an amide ester, a mixture of a fatty acid metal salt and a fatty acid amide, and the like. Processing aids that can be used include those commercially available from Schill+Seilacher GmbH, Performance Additives, etc. A processing aid can be used alone, or two or more can be used in combination.

[0196] The amount of processing aids, when combined, based on 100 parts by mass of the rubber component, is preferably greater than 0.5 parts by mass, more preferably greater than 1 part by mass, and still more preferably greater than 1.5 parts by mass, in order to demonstrate an effect of improving processability. Furthermore, in order to improve abrasion resistance and fracture toughness, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and still more preferably less than 5.0 parts by mass. < <wachs>>

[0197] The type of wax is not particularly restricted, and any wax commonly used in the tire industry may be suitable. Examples include mineral-based waxes, plant-derived waxes, and the like. Mineral-based waxes refer to waxes derived from mineral resources such as oil, natural gas, and the like. Plant-derived waxes refer to waxes derived from natural resources such as plants. Mineral-based waxes are preferred. Examples of plant-derived waxes include rice bran wax, carnauba wax, candelilla wax, and the like. Examples of mineral-based waxes include paraffin wax, microcrystalline wax, a specially selected wax of these, and the like, with paraffin wax being preferred.Furthermore, the wax relating to the present embodiment should not contain stearic acid. For example, waxes commercially available from Ouchi Shinko Chemical Industry Co., Nippon Seiro Co., Ltd., PARAMELT, etc., can be used. These waxes can be used individually, or two or more can be used in combination.

[0198] The wax content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the perspective of improving the weather resistance of the rubber. Furthermore, from the perspective of preventing the whitening of a tire due to blooming, it is preferably less than 10 parts by mass, more preferably less than 7.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Antioxidants)

[0199] Examples of the antioxidant include, but are not limited to, a naphthylamine-based antioxidant such as phenyl-α-naphthylamine and the like; a diphenylamine-based antioxidant such as an octylated diphenylamine, 4,4'-bis(α,α'-dimethylbenzyl)diphenylamine and the like; an antioxidant based on p-phenylenediamine, such as N-isopropyl-N'phenyl-p-phenylenediamine, N-(1,3-dimethylbutyl)-N'-phenylp-phenylenediamine (6PPD), N,N'-bis(1,4-dimethylpentyl)-p-phenylenediamine (77PD), N,N'-diphenyl-p-phenylenediamine (DPPD), N,N'-ditolyl-p-phenylenediamine (DTPD), N-isopropyl-N'-phenyl-p-phenylenediamine (IPPD), N,N'-di-2-naphthyl-p-phenylenediamine (DNPD) and the like; an antioxidant based on quinoline, such as a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline and the like;A monophenol-based antioxidant, such as 2,6-di-t-butyl-4-methylphenol, a styrenized phenol, and the like; and bisphenol-based, trisphenol-based, and polyphenol-based antioxidants, such as tetrakis-[methylene-3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane and the like. Among these, the p-phenylenediamine-based and the quinoline-based antioxidants are preferred, and N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine and a polymer of 2,2,4-trimethyl-1,2-dihydroquinoline are further preferred. Commercially available products may include, for example, those manufactured by Seiko Chemical Co., Ltd., Sumitomo Chemical Co., Ouchi Shinko Chemical Industry Co., Flexsys, etc. These antioxidants can be used alone, or two or more of them can be used in combination.

[0200] The content of an antioxidant, when combined, based on 100 parts by mass of the rubber component (a total amount of all of several antioxidants when used in combination), is preferably greater than 1.0 parts by mass, more preferably greater than 2.0 parts by mass, and still more preferably greater than 2.5 parts by mass, from the point of view of ozone crack resistance of a rubber.

[0201] Furthermore, from the point of view of abrasion resistance and wet adhesion performance, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass and even more preferably less than 5.0 parts by mass. (Stearic acid)

[0202] The stearic acid content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the point of view of processability. Furthermore, from the point of view of vulcanization rate, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Zinc oxide)

[0203] The zinc oxide content, when combined, based on 100 parts by mass of the rubber component, is preferably more than 0.5 parts by mass, more preferably more than 1.0 parts by mass, and even more preferably more than 1.5 parts by mass, from the point of view of processability. Furthermore, from the point of view of abrasion resistance, it is preferably less than 10 parts by mass, more preferably less than 8.0 parts by mass, and even more preferably less than 5.0 parts by mass. (Vulcanizing agent)

[0204] Sulfur is suitable for use as a vulcanizing agent. Suitable forms of sulfur include powdered sulfur, oil-processing sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, highly dispersible sulfur, and the like.

[0205] When combined as a vulcanizing agent, the sulfur content, based on 100 parts by mass of the rubber component, is preferably greater than 0.1 parts by mass, more preferably greater than 0.5 parts by mass, and even more preferably greater than 1.0 parts by mass, to ensure a sufficient vulcanization reaction. Furthermore, to prevent deterioration, it is preferably less than 5.0 parts by mass, more preferably less than 3.0 parts by mass, and even more preferably less than 2.0 parts by mass. Additionally, when an oil-based sulfur is used as the vulcanizing agent, the sulfur content is defined as the total content of pure sulfur contained in the oil-based sulfur.

[0206] A well-known organic crosslinking agent can also be used as a vulcanizing agent other than sulfur. While the choice of organic crosslinking agent is not particularly limited, as long as it can form a crosslinking chain other than polysulfide bonds, examples of organic crosslinking agents include, for example, alkylphenol-sulfur chloride condensate, sodium hexamethylene 1,6-bisthiosulfate dihydrate, 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane, dicumyl peroxide, and the like, with 1,6-bis(N,N'-dibenzylthiocarbamoyldithio)hexane being preferred. These organic crosslinking agents can include those commercially available from Taoka Chemical Co., Ltd., LANXESS, Flexsys, etc. (Vulcanization accelerator)

[0207] Examples of vulcanization accelerators include, but are not limited to, sulfenamide-based vulcanization accelerators, thiazole-based vulcanization accelerators, guanidine-based vulcanization accelerators, thiuram-based vulcanization accelerators, thiourea-based vulcanization accelerators, dithiocarbamic acid salt-based vulcanization accelerators, aldehyde-amine-based vulcanization accelerators, aldehyde-ammonia-based vulcanization accelerators, imidazoline-based vulcanization accelerators, xanthate-based vulcanization accelerators, caprolactam disulfide, and the like. These vulcanization accelerators can be used alone, or two or more of them can be used in combination.Among these, one or more vulcanization accelerators selected from the group consisting of a sulfenamide-based vulcanization accelerator, a thiazole-based vulcanization accelerator, and a guanidine-based vulcanization accelerator are preferred, given that suitable effects can be obtained more appropriately.

[0208] Examples of sulfenamide-based vulcanization accelerators include, for example, N-tert-butyl-2-benzothiazolylsulfenamide (TBBS), N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N,N-dicyclohexyl-2-benzothiazolylsulfenamide (DZ) and the like.

[0209] Examples of thiazole-based vulcanization accelerators include, for example, 2-mercaptobenzothiazole (MBT) or salts thereof, di-2-benzothiazolyl disulfide (MBTS), 2-(2,4-dinitrophenyl)mercaptobenzothiazole, 2-(2,6-diethyl-4-morpholinothio)benzothiazole and the like.

[0210] Examples of guanidine-based vulcanization accelerators include, for example, 1,3-diphenylguanidine (DPG), 1,3-di-o-tolylguanidine, 1-o-tolylbiguanide, di-o-tolylguanidine salt of dicatechol borate, 1,3-di-o-cumenylguanidine, 1,3-di-o-biphenylguanidine, 1,3-di-o-cumenyl-2-propionylguanidine and the like.

[0211] Examples of thiuram-based vulcanization accelerators include, for example, Tetrakis(2-ethylhexyl)thiuram disulfide (TOT-N), Tetramethylthiuram disulfide (TMTD), Tetraethylthiuram disulfide, Tetramethylthiuram monosulfide (TMTM), Dipentamethylenethiuram disulfide, Dipentamethylenethiuram tetrasulfide and the like.

[0212] Examples of thiourea-based vulcanization accelerators include, for example, thiourea compounds such as thiocarbamide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea and the like, N,N'-diphenylthiourea, trimethylthiourea, N,N'-diethylthiourea and the like.

[0213] Examples of dithiocarbamic acid salt-based vulcanization accelerators include, for example, piperidinium pentamethylenedithiocarbamate (PPDC), zinc dimethyldithiocarbamate (ZnMDC), zinc diethyldithiocarbamate (ZnEDC), zinc dibutyldithiocarbamate (ZnBCD), zinc dibenzyldithiocarbamate (ZDBzC), zinc N-ethyl-N-phenyldithiocarbamate (ZnEPDC), zinc N-pentamethylenedithiocarbamate (ZnPDC), sodium dibutyldithiocarbamate (NaBCD), copper dimethyldithiocarbamate (CuMDC), iron dimethyldithiocarbamate (FeMDC), tellurium diethyldithiocarbamate (TeEDC), and the like.

[0214] The content of a vulcanization accelerator, when combined, based on 100 parts by mass of the rubber component (a total amount of all multiple vulcanization accelerators when used in combination), is preferably more than 3.0 parts by mass, further preferably more than 4.0 parts by mass, and even more preferably 5.0 parts by mass or more. Furthermore, the content of the vulcanization accelerator, based on 100 parts by mass of the rubber component, is preferably less than 8.0 parts by mass, further preferably less than 7.0 parts by mass, and even more preferably less than 6.0 parts by mass.

[0215] In the present description, various materials, each comprising a single carbon atom (for example, rubber, oil, resin, vulcanization accelerator, antioxidant, surfactant, and the like), can be derived from carbon dioxide in the atmosphere. One method for obtaining these various materials from carbon dioxide is either the direct conversion of carbon dioxide or the conversion of methane, which is obtained via a methanation process by which methane is synthesized from carbon dioxide. [Production]

[0216] The rubber composition according to the present embodiment can be produced by a known method. It can be produced, for example, by kneading the respective components described above using a rubber kneading machine, such as an open roller, a closed-type kneader (a Banbury mixer, a kneader, and the like), and the like.

[0217] The kneading step includes, for example, a basic kneading step involving the kneading of bonding agents and additives other than a vulcanizing agent and a vulcanization accelerator; and a final kneading step (F-kneading) involving the addition of the vulcanizing agent and the vulcanization accelerator to the kneaded product obtained in the basic kneading step, and the kneading of this mixture. Furthermore, the basic kneading step can also be subdivided into several steps if necessary.In a case of subdividing the basic kneading step, a method of subdividing the basic kneading step may be: (1) a method of first kneading a portion of the binders and additives into a masterbatch and then adding the remaining binders and additives to the resulting masterbatch for kneading; (2) a method of kneading all the binders and additives to be kneaded in the basic kneading step at once and then rolling the kneaded product once or several times; or the like. In method (1) described above, the number of masterbatches is not limited and may be two or more. Furthermore, if the number of masterbatches is two or more, all the binders and additives used in the basic kneading step may be allocated to any one of the masterbatches.

[0218] Examples of kneading conditions include, for instance, a process of kneading at a discharge temperature of 150 °C to 170 °C for 3 to 10 minutes for the initial kneading step and kneading at 70 °C to 110 °C for 1 to 5 minutes for the final kneading step, but they are not particularly limited to these. Examples of vulcanization conditions include, for instance, a process of vulcanizing at 150 °C to 200 °C for 10 to 30 minutes, but they are not particularly limited to these.

[0219] A tire according to the present embodiment, comprising a tread section composed of the rubber composition described above, can be produced by a conventional method. That is, the tire can be produced by extruding an unvulcanized rubber composition, prepared by combining the rubber components described above as required for a specific rubber component, into a tread section mold, by joining the resulting tread section with other tire elements on a tire forming machine, and by forming it using a conventional unvulcanized tire forming method, followed by heating and pressurizing the resulting unvulcanized tire in a vulcanizing machine.Examples of vulcanization conditions include, for example, a process of vulcanizing at 150 °C to 200 °C for 10 to 30 minutes, but are not particularly limited to these. [Applications]

[0220] The tire according to the present embodiment can be used for any application, regardless of whether it is a pneumatic or deflated tire, and can be used as a passenger car tire, a large passenger car tire, a large SUV tire, a racing tire, a motorcycle tire, a heavy-duty tire, or a run-flat tire. Furthermore, "passenger car tire" refers to a tire intended for mounting on a four-wheeled vehicle and having a maximum load capacity of less than 1400 kg. "Heavy-duty tire" refers to a tire with a maximum load capacity of 1400 kg or more.Furthermore, according to the present embodiment, the tire can be used as an all-season tire, a summer tire, and a winter tire, such as a spikeless tire. EXAMPLES

[0221] Examples considered preferred in implementing the present invention (examples) are described below, although the scope of protection of the present invention is not limited to these examples. Results calculated on the basis of the evaluation methods described below, taking into account a tire obtained according to Table 1 or 2 using various chemicals described below, are shown in Tables 1 and 2.

[0222] Examples of embodiments of the present invention are described below. NR: TSR 20 SBR1: SBR produced using production example 1 described below (S-SBR, Tg: -60 °C, styrene content: 20 wt%, vinyl content: 20 mol%, Mw: 700,000, not oil-diluted) SBR2: Tufdene 3830, manufactured by Asahi Kasei Corporation (unmodified S-SBR, Tg: -35 °C, styrene content: 36 wt%, vinyl content: 31 mol%, Mw: 420,000, comprising 37.5 wt parts of a stretched oil content based on 100 wt parts of a rubber solids content) BR: Ubepol BR (registered trademark) 150B, manufactured by UBE Corporation (unmodified BR, cis content: 97 wt%, Mw: 440,000) Soot: Soot from the prototype (N2SA): 180 m 2 / g, average primary particle size: 16 nm) Silicon dioxide: Ultrasil VN3, manufactured by Evonik Industries AG (N2SA: 175 m 2 / g, average primary particle size: 17 nm) Silane coupling agent: Si266, manufactured by Evonik Industries AG (Bis(3-triethoxysilylpropyl)disulfide) Resin component 1: Oppera PR395, manufactured by Exxon Mobil Chemical (hydrogenated DCPD / C9 resin, resin comprising dicyclopentadiene, styrene and indene as monomer components, softening point: 118 °C) Resin component 2: SYLVATRAXX 4401, manufactured by Kraton Corporation (α-methylstyrene resin, softening point: 85 °C) Oil: VivaTec 500, manufactured by H&R Group (TDAE Oil). Wax: OZOACE 0355 (paraffin wax), manufactured by Nippon Seiro Co., Ltd. Antioxidant 1: Nocrac 6C, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine) Antioxidant 2: Nocrac RD, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (Poly(2,2,4-trimethyl-1,2-dihydroquinoline)) Stearic acid: Stearic acid “CAMELLIA”, manufactured by NOF CORPORATION Zinc oxide: Zinc oxide No. 1, manufactured by Mitsui Mining & Smelting Co., Ltd. Sulfur: HK-200-5, manufactured by Hosoi Chemical Industry Co., Ltd. (5% oil-based sulfur powder) Vulcanization accelerator 1: Nocceler CZ, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (N-Cyclohexyl-2-benzothiazolylsulfenamide (CBS)) Vulcanization accelerator 2: Nocceler D, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. (1,3-Diphenylguanidine (DPG)) (Production example 1: Production of SBR1)

[0223] Cyclohexane, tetrahydrofuran, styrene, and 1,3-butadiene are loaded into a nitrogen-purged autoclave reactor. The ratio of styrene to 1,3-butadiene is adjusted to achieve a styrene content of 20 wt%. After adjusting the temperature of the reactor contents to 20 °C, n-butyllithium is added to initiate polymerization. Polymerization is carried out under adiabatic conditions, and the temperature reaches 80 °C, the maximum operating temperature. After verifying the production of a polymer with a molecular weight of 700,000 by GPC, a polymerization solution is poured into 4 L of ethanol to collect a precipitate. After drying the precipitate with a hairdryer, it is dried under reduced pressure at 80 °C / 10 Pa or lower until a loss on drying of 0.1% is achieved, yielding SBR1. (Examples and comparative examples)

[0224] According to the compound formulations shown in Table 1 or Table 2, chemicals other than sulfur and vulcanization accelerator are kneaded using a closed 1.7-liter Banbury mixer for 4 minutes at a discharge temperature of 160 °C to obtain a kneaded product. Next, using an open roller, sulfur and the vulcanization accelerator are added to the resulting kneaded product, and the mixture is kneaded for 4 minutes until the temperature reaches 105 °C to obtain an unvulcanized rubber composition.The resulting unvulcanized rubber compound is molded into a tread section, and the molded rubber compound is assembled with other tire elements to produce an unvulcanized tire. The unvulcanized tire is then vulcanized at 170 °C, yielding each test tire (size: 205 / 65R15, rim: 15 × 6JJ, internal pressure: 230 kPa). The thickness t2 of the rubber base layer is 1.5 mm. The thickness t1 of the rubber top layer is calculated as (total thickness T of the tread section shown in the table) - (thickness t2 of the rubber base layer described above). A thickness B of a belt rubber layer is 1.0 mm, and a groove depth of the deepest part of a circumferential groove present in a shoulder area corresponds to "groove depth H of deepest part of circumferential groove (mm)" shown in the table.Furthermore, a lateral groove present in a central area is a widened groove with a . Fig. 4 cross-sectional shape shown. <Messung von durch Aceton extrahierbarer Menge (AE-Menge)>

[0225] An AE quantity is measured for each rubber test piece produced by cutting out a tread section of each test tire. The AE quantity is calculated using the following equation after each vulcanized rubber test piece has been immersed in acetone at room temperature (around 25°C) for 24 hours in accordance with JIS K 6229:2015 to extract a soluble component, and a mass of each test piece is measured before and after extraction. Amount extractable by acetone (mass −%) = {(mass of vulcanized rubber test piece before extraction − mass of vulcanized rubber test piece after extraction) / (mass of vulcanized rubber test piece before extraction)} × 100. <Messungen von 30 °C-tanδ und 0 °C-tanδ>

[0226] For each rubber test piece, prepared to have a length of 20 mm, a width of 4 mm, and a thickness of 1 mm by cutting it from a tread section of each test tire, such that one tire circumference direction becomes a long side and one tire radial direction becomes a thickness direction, a loss tangent tanδ is measured using a dynamic viscoelasticity measuring device (EPLEXOR series, manufactured by gabo Systemtechnik GmbH) under a temperature of 30 °C, a frequency of 10 Hz, an initial strain of 5%, a dynamic strain of ± 1%, and a strain mode. Additionally, a loss tangent tanδ is measured under a temperature of 0 °C, a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ± 2.5%, and a strain mode. <Messung von Glasübergangstemperatur (Tg) von Kautschukzusammensetzung>

[0227] For each rubber test piece, prepared to have a length of 20 mm, a width of 4 mm and a thickness of 1 mm by cutting it from a tread section of each test tire such that one tire circumference direction becomes a long side and one tire radial direction becomes a thickness direction, a temperature distribution curve of tanδ is measured in a range from -60 °C to 40 °C under a frequency of 10 Hz, an initial strain of 10%, a dynamic strain of ± 0.5% and a temperature rise rate of 2 °C / min using a dynamic viscoelasticity measuring device (EPLEXOR series manufactured by gabo Systemtechnik GmbH) and a temperature corresponding to the largest tanδ value in the obtained temperature distribution curve (tanδ peak temperature) is determined as Tg of a rubber composition. <brennstoffeffizienz>

[0228] The rolling resistance of each test tire is measured using a rolling resistance tester when the test tire is subjected to conditions of a 15×6JJ rim, an internal pressure of 230 kPa, a load of 4.24 kN, and a speed of 80 km / h. The inverse of the rolling resistance is expressed as an index, where a tire of comparison example 2 is 100. The results show that the higher the index, the lower the rolling resistance and the better the fuel efficiency. <nasshaftungsleistung>

[0229] Each test tire is mounted on each of the four wheels of a 2000 cc passenger car, and a braking distance is measured from the point where the vehicle, traveling at 100 km / h on a wet road surface, has come to a complete stop. Furthermore, the wet grip performance of each tire is expressed as an index using the following equation, where the braking distance of a test tire from comparison example 2 is 100. The results show that the higher the index, the better the wet grip performance. (Wet grip performance index)=(Braking distance of test tires from comparison example 2) / (Braking distance of each test tire)×100. <gesamtleistung>

[0230] A combined value for fuel efficiency and wet grip performance, as described above, is given as an overall performance index. Table 1 Example 1 2 3 4 5 6 7 8 9 10 Composite quantity (mass parts) NR 40 40 40 40 40 40 40 40 40 70 SBR1 40 40 40 40 40 40 40 40 40 30 BR 20 20 20 20 20 20 20 20 20 - soot 35 25 10 35 10 15 10 10 10 10 silicon dioxide 45 65 55 45 65 65 55 65 65 65 Silane coupling agent 3,6 5,2 4,4 3,6 5,2 5,2 4,4 5,2 5,2 5,2 (Resin component) 1 15 15 15 30 15 30 30 30 30 30 Öl 10 10 10 10 10 10 10 10 10 10 wax 2,0 2,0 2, 0 2, 0 2, 0 2, 0 2,0 2,0 2,0 2,0 Antioxidant 1 2,0 2,0 2, 0 2, 0 2, 0 2, 0 2,0 2,0 2,0 2,0 Antioxidants 2 1,0 1,0 1, 0 1, 0 1, 0 1, 0 1,0 1,0 1,0 1,0 Stearic acid 2,0 2,0 2, 0 2, 0 2, 0 2, 0 2,0 2,0 2,0 2,0 zinc oxide 2,0 2,0 2, 0 2, 0 2, 0 2, 0 2,0 2,0 2,0 2,0 sulfur 1,4 1,4 1,4 1,4 1,4 1,4 1,4 1,4 1,4 1,4 Vulcanization accelerator 1 2,0 2,0 2, 0 2, 0 2, 0 2, 0 2,0 2,0 2,0 2,0 Vulcanization accelerator 2 2,0 2,0 2, 0 2, 0 2, 0 2, 0 2,0 2,0 2,0 2,0 Styrene content S1 of SBR (mass %) 20 20 20 20 20 20 20 20 20 20 Acetone-extractable amount AE (mass-%) 16,3 16,2 17,4 21,5 16,5 21,4 22, 9 21, 9 21, 9 22,1 30 °C-tanδ 0,25 0,22 0,19 0,30 0,21 0,25 0,21 0,23 0,23 0,24 0 °C tanδ 0, 43 0, 42 0,39 0,57 0,41 0,57 0,56 0,56 0,56 0,61 Tg of rubber composition (°C) -39 -37 -36 -34 -36 -34 -32 -34 -34 -26 Total amount of styrene S2 in rubber component (mass %) 8,0 8,0 8,0 8,0 8,0 8,0 8,0 8,0 8,0 14,0 Groove depth H of deepest part of circumferential groove (mm) 7,0 7,0 7,0 5,0 7,0 5,0 5,0 5,0 4,7 5,0 AE × H 114 113 122 108 116 107 115 110 103 111 Survey ratio R 0, 80 0, 80 0,80 0,80 0,80 0,80 0, 80 0,80 0,80 0,80 SlxR 16,0 16,0 16,0 16,0 16,0 16,0 16,0 16,0 16,0 16,0 Total thickness T of tread section (mm) 8,0 8,0 8,0 8,0 8,0 8,0 8,0 8,0 5,0 8,0 30 °C-tanδ × T 2,0 1,8 1,5 2,4 1,7 2,0 1,7 1,8 1,2 1,9 Tire weight G (kg) 10 10 10 10 10 10 10 10 10 10 S1 / G 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Evaluation Fuel efficiency 107 124 131 105 137 125 138 143 172 133 Wet adhesion performance 103 109 106 119 112 127 127 134 134 144 Total performance 210 233 237 224 249 252 265 277 306 277 Table 2 comparative example 1 2 3 4 5 6 7 Composite quantity (mass parts) NR 40 20 40 40 40 40 40 SBR1 - 60 40 40 40 40 40 SBR2 55 - - - - - - (Oil content) (15) BR 20 20 20 20 20 20 20 soot 35 35 35 35 35 35 35 silicon dioxide 45 45 45 45 20 45 45 Silane coupling agent 3,6 3,6 3,6 3,6 1,6 3,6 3,6 (Resin component) 1 - 13 - - 10 15 15 (Resin component) 2 - - - 20 - - - Öl 10 10 10 10 10 10 10 wax 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Antioxidant 1 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Antioxidants 2 1,0 1,0 1,0 1,0 1,0 1,0 1,0 Stearic acid 2,0 2,0 2,0 2,0 2,0 2,0 2,0 zinc oxide 2,0 2,0 2,0 2,0 2,0 2,0 2,0 sulfur 1,4 1,4 1,4 1,4 1,4 1,4 1,4 Vulcanization accelerator 1 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Vulcanization accelerator 2 2,0 2,0 2,0 2,0 2,0 2,0 2,0 Styrene content S1 of SBR (mass %) 36 20 20 20 20 20 20 Acetone-extractable amount AE (mass-%) 16,3 17,2 10,2 16,3 16,4 16,3 16,3 30 °C-tanδ 0,27 0,24 0,22 0,26 0,21 0,25 0,25 0 °C-tan6 0,38 0,46 0,35 0,35 0,35 0,43 0,43 Tg of rubber composition (°C) -42 -37 -42 -38 -39 -39 -39 Total amount of styrene S2 in rubber component (mass %) 14,4 12,0 8,0 8,0 8,0 8,0 8,0 Groove depth H of deepest part of circumferential groove (mm) 7,0 7,0 7,7 7,0 7,0 7,0 7,0 AE × H 114 120 79 114 115 114 114 Survey ratio R 0,80 0,80 0,80 0,80 0,80 0,80 0,80 S1×R 28,8 16,0 16,0 16,0 16,0 16,0 16,0 Total thickness T of tread section (mm) 8,0 8,0 8,0 8,0 8,0 12,0 8,0 30 °C-tanδ × T 2,2 1,9 1,8 2,1 1,7 3,0 2,0 Tire weight G (kg) 10 10 10 10 10 10 10 S1 / G 3,6 2,0 2,0 2,0 2,0 2,0 2,0 Evaluation Fuel efficiency 85 100 103 96 104 76 97 Wet adhesion performance 92 100 94 96 95 99 99 Total performance 178 200 197 192 199 175 196 <Ausführungsformen>

[0231] Examples of embodiments of the present invention are described below. [1] A tire is provided comprising a tread section, the tread section comprising one or more circumferential grooves, the tread section being composed of a rubber composition comprising a rubber component and silicon dioxide, and a resin component, the rubber component comprising an isoprene-based rubber and a styrene-butadiene rubber, wherein the content of the isoprene-based rubber in the rubber component is 40 wt% or more, wherein the styrene content S1 in wt% of the styrene-butadiene rubber is 30 or less, wherein the content of the silicon dioxide based on 100 wt% of the rubber component is 30 wt% or more, the resin component comprising a dicyclopentadiene-based resin, wherein the amount of AE extractable by acetone in wt% of the rubber composition is 16.0 wt% or greater, wherein,where 30 °C-tanδ represents a tanδ at 30 °C of the rubber composition and T in mm represents a total thickness of the tread section, 30 °C-tanδ × T is less than 3.0 and where H in mm represents a groove depth of a deepest part of the circumferential groove, AE × H is 100.0 or more. [2] The tire of [1] above, wherein the silicon dioxide content based on 100 parts by mass of the rubber component is preferably 60 parts by mass or more. [3] The tire of [1] or [2] above, wherein the rubber composition comprises 1 part by mass or more and 10 parts by mass or less of carbon black based on 100 parts by mass of the rubber component. [4] The tire from one of [1] to [3] above, where 30 °C-tanδ is 0.26 or more. [5] The tire of one of claims [1] to [4] above, wherein 30 °C-tanδ × T is less than 2.6. [6] The tire of one of [1] to [5] above, where S1 is 25 or less. [7] The tire from one of [1] to [6] above, wherein the total amount of styrene S2 in mass % in the rubber component is 15 or less. [8] The tire from one of [1] to [7] above, wherein a tanδ at 0 °C of the rubber composition (0 °C-tanδ) is 0.45 or more. [9] The tire from one of [1] to [8] above, wherein, where R represents a height ratio of the tread section, S1 × R is 11.0 or more, preferably 12.0 or more and more preferably 13.0 or more and 20.0 or less.

[10] The tire according to one of [1] to [9] above, wherein, where G in kg represents a tire weight, S1 / G is 3.0 or less and preferably 1.2 or more and 2.5 or less.

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

[10] above, wherein the resin is based on dicyclopentadiene and is a resin comprising dicyclopentadiene, styrene and indene as monomer components.

[12] The tire from [1] to

[11] above, wherein the tread section has a rib section which is separated by one or more circumferential grooves, wherein the rib section has lateral grooves which extend to an inside in a tire radial direction and wherein at least one of the lateral grooves has a groove width which is wider than a groove width on a tread surface on the inside in the tire radial direction.

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

[12] above, wherein, in a tread surface of the tread section, where an area of ​​30% of a tread ground contact width centered on a tire equator is defined as a central area, and areas that are both outer sides of the central area and are within the tread ground contact width are defined as a pair of shoulder areas, a groove depth of the deepest part of the circumferential groove present in the shoulder areas is 6.0 mm or more.

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

[13] above, wherein, where t1 in mm represents a thickness of a layer of the tread section whose outer surface forms a tread surface and B in mm represents a thickness of a belt layer of the tread section, B is 0.9 or more and 1.2 or less and t1 / B is 7.0 or less.

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

[14] , wherein a groove base thickness of the tread section is 1.0 mm or more and 4.0 mm or less. REFERENCE MARK LIST 1 tread section 2 side wall section 3 bead section 4 Carcass 5 belt layer 6 strip layer 7 Innerliner 8 rim 9 rim tape 10 Clinch section 11. Layer, whose outer surface forms the running surface (rubber top layer) 12 Rubber base layer 13 Bead Tape 14 bead core CL tire equator H Groove depth of deepest part of circumferential grooves P center point in tire width direction N line perpendicular to the tangent plane at point P Total thickness of tread section B Thickness of belt layer t1 Layer thickness whose outer surface forms the running surface (rubber top layer) t2 Thickness of rubber base layer 15 circumferential groove 16 Tread surface 17 Straight line connecting the ends of the circumferential groove 18 Extension line from outer surface of rubber base layer 19 Extension line from deepest part of circumferential groove 20 Bridge section 21 middle bridge section 22 Shoulder strap section 31 side groove 32 side groove TW tread surface ground contact width CR Midrange SR shoulder area Te tread end 40 grooved floor 41 groove edge 42 grooved wall W1 Opening width (groove width on tread surface) C1 Depth of groove edge to groove bottom C2 Depth of groove edge to groove bottom< / gesamtleistung> < / nasshaftungsleistung> < / brennstoffeffizienz> < / wachs> < / verarbeitungshilfsmittel> < / gehalt> < / erweichungspunkt> < / weichmacher> < / silankupplungsmittel> < / kautschukkomponente>

Claims

[1] Tire comprising a tread section, wherein the tread section comprises one or more circumferential grooves, wherein the tread section is composed of a rubber composition comprising a rubber component and silicon dioxide, and a resin component, wherein the rubber component comprises an isoprene-based rubber and a styrene-butadiene rubber, where the content of isoprene-based rubber in the rubber component is 40% by mass or more, where the styrene content S1 in mass % of the styrene-butadiene rubber is 30 or less, where the silicon dioxide content is 30 parts by mass or more based on 100 parts by mass of the rubber component, wherein the resin component comprises a dicyclopentadiene-based resin, where the amount of AE extractable by acetone is 16.0 or more in mass % of the rubber composition, where, if 30 °C-tanδ represents a tanδ at 30 °C of the rubber composition and T in mm represents a total thickness of the tread section, 30 °C-tanδ × T is less than 3.0, and where H in mm represents a groove depth of the deepest part of the circumferential groove, AE × H is 100.0 or more. [2] Tire according to claim 1, wherein the silicon dioxide content based on 100 parts by mass of the rubber component is preferably 60 parts by mass or more. [3] Tire according to claim 1 or 2, wherein the rubber composition comprises 1 part by mass or more and 10 parts by mass or less of carbon black based on 100 parts by mass of the rubber component. [4] Tires according to any one of claims 1 to 3, wherein 30 °C-tanδ is 0.26 or less. [5] Tires according to any one of claims 1 to 4, wherein 30 °C-tanδ × T is less than 2.

6. [6] Tires according to any one of claims 1 to 5, wherein S1 is 25 or less. [7] Tires according to any one of claims 1 to 6, wherein the total amount of styrene S2 in mass % in the rubber component is 15 or less. [8] Tires according to any one of claims 1 to 7, wherein the tanδ at 0 °C of the rubber composition (0 °C-tanδ) is 0.45 or more. [9] Tires according to any one of claims 1 to 8, wherein, where R represents a height ratio of the tread section, S1 × R is 11.0 or more. [10] Tires according to any one of claims 1 to 9, wherein, where G in kg represents a tire weight, S1 / G is 3.0 or less. [11] Tires according to any one of claims 1 to 10, wherein the dicyclopentadiene-based resin is a resin comprising dicyclopentadiene, styrene and indene as monomer components. [12] Tires according to any one of claims 1 to 11, wherein the tread section has a web section which is separated by one or more circumferential grooves, wherein the rib section has lateral grooves that extend in a tire radial direction towards an inside, and wherein at least one of the lateral grooves has a groove width on the inside in the tire radial direction which is wider than a groove width on a tread surface. [13] Tires according to any one of claims 1 to 12, wherein, in a tread surface of the tread section, where an area of ​​30% of a tread ground contact width centered on a tire equator is defined as a central area and areas which are both outer sides of the central area and are located within the tread ground contact width are defined as a pair of shoulder areas, the groove depth of the deepest part of the circumferential groove present in the shoulder areas is 6.0 mm or more. [14] Tires according to any one of claims 1 to 13, wherein, where t1 in mm represents a thickness of a layer of the tread section whose outer surface forms a tread surface and B in mm represents a thickness of a belt layer of the tread section, B is 0.9 or more and 1.2 or less and t1 / B is 7.0 or less. [15] Tires according to any one of claims 1 to 14, wherein a groove base thickness of the tread section is 1.0 mm or more and 4.0 mm or less.

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