JP6658831B2 - High performance tires - Google Patents

Description

  The present invention relates to a high-performance tire having a tread constituted by a predetermined rubber composition.

  It is desired that treads for high-performance tires maintain excellent steering stability (grip performance) on a dry road surface (dry road surface) from the beginning of traveling to the end of traveling. That is, it is desired that the grip performance during running is maintained good together with the excellent initial grip performance.

  Conventionally, for the purpose of improving the initial grip performance, a method of increasing the amount of the liquid polymer in the tread rubber composition and a method of incorporating a low-temperature softener have been studied. However, although the initial grip performance is improved by these methods, there is a problem that the grip performance during traveling decreases as the temperature of the tread increases. In addition, since a double bond is present in the liquid polymer, there is a problem that crosslinking is loosened and wear resistance is reduced.

  On the other hand, for the purpose of obtaining stable grip performance during running, a method of blending an adhesive resin into a tread rubber composition has been studied. However, although stable grip performance during running can be obtained by blending the adhesive resin, there is a problem that the initial grip performance is greatly reduced.

  Patent Document 1 discloses that a rubber component contains an amine / ketone antioxidant, a mixed resin obtained by mixing two or more resins, stearic acid, and zinc oxide, so that good production load and aging resistance can be obtained. While ensuring, tread rubber composition for high performance tires with excellent grip performance, initial grip performance, abrasion resistance and appearance characteristics are described, but the important performance of high performance tires is abrasion resistance, running There is still room for improvement in grip performance and initial grip performance.

JP 2014-105273 A

  An object of the present invention is to provide a high-performance tire capable of simultaneously improving the initial grip performance on a dry road surface and the stable grip performance during running at a high level while maintaining sufficient wear resistance.

  The present inventors have conducted intensive studies and found that the rubber composition contains a predetermined amount of an adhesive resin and a softening agent containing a predetermined amount of a low-temperature plasticizer, so that the grip performance during traveling can be maintained while maintaining abrasion resistance. The present inventors have found that the above problem can be solved by greatly improving the initial grip performance while maintaining the effect of improving the above, and further studied and completed the present invention.

  That is, the present invention is a high-performance tire having a tread composed of a rubber composition containing a rubber component and a softening agent, wherein the softening agent has an adhesion of 35 to 100 parts by mass with respect to 100 parts by mass of the rubber component. The present invention relates to a high-performance tire which is a softener containing a resin and 10 to 50 parts by mass of a low-temperature plasticizer.

  It is preferable that the content of the adhesive resin in the softener is 25% by mass or more.

  It is preferable that the ratio of the content of the adhesive resin to the content of the low-temperature plasticizer (the content of the adhesive resin / the content of the low-temperature plasticizer) is 1.0 to 3.0.

  The softening point of the pressure-sensitive adhesive resin is preferably from 80 to 170 ° C.

  It is preferable that the adhesive resin is at least one selected from the group consisting of a phenolic resin, a coumarone indene resin, a terpene resin, and an acrylic resin.

  The low-temperature plasticizer preferably has a freezing point of -50 ° C or lower.

  It is preferable that the viscosity of the low-temperature plasticizer at 25 ° C. is 30 mPa · s or less.

  According to the present invention, a rubber component, and a high performance tire having a tread composed of a rubber composition containing a softener containing a predetermined amount of an adhesive resin and a predetermined amount of a low-temperature plasticizer, sufficient It is possible to provide a high-performance tire capable of simultaneously improving the initial grip performance particularly on a dry road surface and the stable grip performance during running at a high level while maintaining abrasion resistance.

  The high performance tire of the present invention is characterized by having a tread constituted by a rubber component and a rubber composition containing a softener containing an adhesive resin and a low-temperature plasticizer.

  Examples of the rubber component include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), styrene isoprene butadiene rubber (SIBR), ethylene propylene diene rubber (EPDM), and chloroprene. Diene rubbers such as rubber (CR), acrylonitrile butadiene rubber (NBR), and butyl rubber (IIR). These rubber components may be used alone or in combination of two or more. Among them, NR, BR, and SBR are preferred, and SBR is more preferred, because grip performance and wear resistance can be obtained in a well-balanced manner. The rubber component in the present specification is a rubber component that is compounded separately from a liquid diene polymer described below.

  The SBR is not particularly limited, and emulsion-polymerized styrene-butadiene rubber (E-SBR), solution-polymerized styrene-butadiene rubber (S-SBR), and modified SBR (modified E-SBR, modified S- SBR) and the like commonly used in the tire industry can be used. Above all, S-SBR is preferred from the viewpoint of achieving both abrasion resistance and stable grip performance during running.

The styrene content of the SBR is preferably at least 20% by mass, more preferably at least 25% by mass. If the styrene content of the SBR is less than 20% by mass, sufficient grip performance tends to not be obtained. Further, the styrene content of the SBR is preferably 60% by mass or less, more preferably 50% by mass or less. When the styrene content of the SBR exceeds 60% by mass, not only does the wear resistance decrease, but also the temperature dependency increases, and the performance change with temperature changes increases. There is a tendency that good results cannot be obtained. The styrene content of SBR in the present specification is a value calculated by H ¹ -NMR measurement.

  When SBR is contained, the content of SBR in the rubber component is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 60% by mass or more. When the content of SBR is less than 10% by mass, sufficient heat resistance, grip performance, and abrasion resistance tend not to be obtained. The upper limit of the SBR content is not particularly limited, and is most preferably 100% by mass from the viewpoint of achieving both abrasion resistance and stable grip performance during running.

  The softening agent is a softening agent containing an adhesive resin and a low-temperature plasticizer.By improving the reduction of the initial grip performance by combining the adhesive resin with the low-temperature plasticizer, the initial grip performance and the good running performance are improved. Grip performance can be improved to a higher level at the same time.

  Examples of the adhesive resin include resins commonly used in conventional rubber compositions for tires, such as aromatic petroleum resins. Examples of the aromatic petroleum resin include a phenolic resin, a coumarone indene resin, a terpene resin, a styrene resin, an acrylic resin, a rosin resin, and a dicyclopentadiene resin (DCPD resin). Examples of the phenolic resin include colesin (manufactured by BASF) and tacky roll (manufactured by Taoka Chemical Industry Co., Ltd.). Examples of the coumarone indene resin include Escron (manufactured by Nippon Steel Chemical Co., Ltd.) and neopolymer (manufactured by JX Nippon Oil & Energy). Examples of the styrene resin include Sylvatraxx 4401 (manufactured by Arizona chemical). Examples of the terpene resin include TR7125 (manufactured by Arizona chemical) and TO125 (manufactured by Yashara Chemical Co., Ltd.). These adhesive resins may be used alone or in combination of two or more. Above all, it is preferable to use a phenolic resin, a coumarone indene resin, a terpene resin, and an acrylic resin because of excellent grip performance during running.

  Further, it is more preferable to use an adhesive resin having a low softening point (low softening point resin) and an adhesive resin having a high softening point (high softening point resin) in combination. By blending a resin having a low softening point, the initial grip performance can be further improved, and by blending a resin having a high softening point, a more stable grip performance during running can be obtained.

  The softening point of the low softening point resin is preferably 60 ° C. or higher, more preferably 70 ° C. or higher. If the softening point is less than 60 ° C., stable grip performance during running may not be obtained. The softening point of the low softening point resin is preferably 115 ° C. or lower, more preferably 110 ° C. or lower. If the softening point exceeds 115 ° C., the initial grip performance may be reduced.

  The low softening point resin is not particularly limited as long as the resin has a softening point within the above range, but among them, a cumarone indene resin is preferable because a stable grip performance during running can be obtained.

  The softening point of the high softening point resin is preferably 120 ° C. or higher, more preferably 140 ° C. or higher. If the softening point is lower than 120 ° C., stable grip performance during running may not be obtained. The softening point of the high softening point resin is preferably 170 ° C. or lower, more preferably 150 ° C. or lower. If the softening point exceeds 170 ° C., the initial grip performance may be reduced.

  The high softening point resin is not particularly limited as long as the resin has a softening point within the above range. Among them, a terpene resin is preferable because of its excellent balance with the initial grip performance.

  In addition, the softening point of the low softening point resin and the high softening point resin in the present specification is obtained by measuring the softening point specified by JIS K 6220-1: 2001 with a ring and ball softening point measuring device, is there.

  The content of the adhesive resin with respect to 100 parts by mass of the rubber component is 35 parts by mass or more, preferably 45 parts by mass or more, and more preferably 50 parts by mass or more. When the content of the adhesive resin is less than 35 parts by mass, stable grip performance during running tends to be not obtained. Further, the content of the adhesive resin is 100 parts by mass or less, preferably 90 parts by mass or less, and more preferably 80 parts by mass or less. When the content of the pressure-sensitive adhesive resin exceeds 100 parts by mass, the tackiness of the unvulcanized rubber composition tends to increase, and the processability tends to deteriorate.

  Further, the content of the pressure-sensitive adhesive resin is preferably 25% by mass or more, more preferably 30% by mass or more in the softener, since good grip performance during running can be obtained. The upper limit of the content of the adhesive resin in the softener is not particularly limited, but is not more than 75% by mass in relation to the content of the low-temperature plasticizer. The content of the pressure-sensitive adhesive resin in the softener refers to the content of the pressure-sensitive adhesive resin in the total content of the pressure-sensitive resin, the low-temperature plasticizer, the oil, and the liquid diene polymer contained in the rubber composition according to the present invention. Quantity.

  Examples of the low-temperature plasticizer include dibutyl adipate (DBA), diisobutyl adipate (DIBA), dioctyl adipate (DOA), di-2-ethylhexyl azelate (DOZ), dibutyl sebacate (DBS), and 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 other ester-based plasticizers. Balun with plasticizing effect and wear resistance From, DOS, TOP is preferable.

  The freezing point of the low-temperature plasticizer is preferably −50 ° C. or lower, more preferably −70 ° C. or lower, because a sufficient initial grip improving effect can be obtained. The lower limit of the freezing point of the low-temperature plasticizer is not particularly limited.

  The viscosity of the low-temperature plasticizer at 25 ° C. is preferably 30 mPa · s or less, more preferably 20 mPa · s or less, because a sufficient initial grip improving effect can be obtained. The lower limit of the viscosity of the low-temperature plasticizer is not particularly limited.

  The content of the low-temperature plasticizer with respect to 100 parts by mass of the rubber component is 10 parts by mass or more, preferably 20 parts by mass or more, and more preferably 30 parts by mass or more. When the content of the low-temperature plasticizer is less than 10 parts by mass, there is a tendency that sufficient initial grip performance cannot be obtained. The content of the low-temperature plasticizer is 50 parts by mass or less, preferably 45 parts by mass or less, and more preferably 40 parts by mass or less. When the content of the low-temperature plasticizer exceeds 50 parts by mass, stable grip performance during running tends to be not obtained.

  Further, the ratio of the content of the adhesive resin to the content of the low-temperature plasticizer (the content of the adhesive resin / the content of the low-temperature plasticizer) is preferably 1.0 or more, and more preferably 1.2 or more. If the content ratio is less than 1.0, there is a possibility that stable grip performance during sufficient running may not be obtained. Further, the content ratio is preferably 3.0 or less, and more preferably 2.5 or less. If the content ratio exceeds 3.0, sufficient initial grip performance may not be obtained.

  The rubber composition according to the present invention may further contain an oil (including a polymer oil fraction) or a liquid diene polymer as a softening agent, from the viewpoints of initial grip performance, stable grip performance during running, and the like. Is preferred.

  Examples of the oil include process oils such as paraffin-based, aroma-based, and naphthenic-based process oils.

  When the oil is contained, the content of the oil with respect to 100 parts by mass of the rubber component is preferably 15 parts by mass or more, more preferably 30 parts by mass or more. When the content of the oil is less than 15 parts by mass, the effect of the addition tends not to be obtained. Further, the content of oil is preferably 85 parts by mass or less, more preferably 75 parts by mass or less. If the oil content exceeds 85 parts by mass, the abrasion resistance tends to deteriorate. In addition, the oil content in the present specification includes an oil component contained in the oil-extended rubber.

  The liquid diene-based polymer is a diene-based polymer in a liquid state at normal temperature (25 ° C.), for example, a liquid styrene-butadiene copolymer (liquid SBR), a liquid butadiene polymer (liquid BR), a liquid isoprene polymer (Liquid IR) and liquid styrene isoprene copolymer (liquid SIR). Above all, liquid SBR is preferable because abrasion resistance and stable grip performance during running can be obtained in a well-balanced manner.

The weight average molecular weight (Mw) of the liquid diene polymer is preferably 1.0 × 10 ³ or more, more preferably 3.0 × 10 ³ or more. When the Mw of the liquid diene polymer is less than 1.0 × 10 ³ , the abrasion resistance and the destructive properties are reduced, and sufficient durability tends not to be secured. The Mw of the liquid diene polymer is preferably 2.0 × 10 ⁵ or less, more preferably 1.5 × 10 ⁴ or less. When the Mw of the liquid diene polymer exceeds 2.0 × 10 ⁵ , the viscosity of the polymerization solution tends to be too high, and the productivity tends to deteriorate. The Mw of the liquid diene polymer in the present specification is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

  When the liquid diene-based polymer is contained, the content of the liquid diene-based polymer relative to 100 parts by mass of the rubber component is preferably at least 20 parts by mass, more preferably at least 30 parts by mass. When the content of the liquid diene polymer is less than 20 parts by mass, sufficient grip performance tends not to be obtained. Further, the content of the liquid diene polymer is preferably at most 80 parts by mass, more preferably at most 40 parts by mass. When the content of the liquid diene polymer exceeds 80 parts by mass, the abrasion resistance tends to deteriorate.

  The content of the softener (the total content of the adhesive resin, the low-temperature plasticizer, the oil, and the liquid diene polymer) is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, based on 100 parts by mass of the rubber component. Preferably, the amount is 120 parts by mass or more. Further, the content of the softener is preferably 250 parts by mass or less, more preferably 200 parts by mass or less, and further preferably 180 parts by mass or less. When the content of the softener is within the above range, the effects of the present invention can be more suitably obtained.

  The rubber composition according to the present invention, in addition to the components, compounding agents conventionally used in the rubber industry, for example, carbon black, silica, calcium carbonate, alumina, clay, reinforcing fillers such as talc, wax, Zinc oxide, stearic acid, various antioxidants, vulcanizing agents, vulcanization accelerators and the like can be appropriately compounded.

  The reinforcing filler preferably contains carbon black because of excellent abrasion resistance. Examples of the carbon black include carbon black produced by an oil furnace method, and two or more types having different colloidal properties may be used in combination. Specific examples include GPF, HAF, ISAF, SAF, etc. Among them, SAF is preferable.

Nitrogen adsorption specific surface area (N ₂ SA) of carbon black is preferably not less than 100 m ² / g, more preferably at least 105m ² / g, more 110m ² / g is more preferred. If the N ₂ SA is less than 100 m ² / g, the grip performance tends to decrease. The N ₂ SA of the carbon black is preferably at most 600 m ² / g, more preferably at most 250 m ² / g, even more preferably at most 180 m ² / g. If the N ₂ SA of the carbon black exceeds 600 m ² / g, the dispersibility tends to be poor and the abrasion resistance tends to decrease. The N ₂ SA of carbon black in the present specification is a value measured according to JIS K6217-2: 2001.

  The DBP oil absorption of carbon black is preferably 50 ml / 100 g or more, and more preferably 100 ml / 100 g or more. If the DBP oil absorption is less than 50 ml / 100 g, sufficient abrasion resistance tends not to be obtained. The DBP oil absorption of carbon black is preferably 250 ml / 100 g or less, more preferably 200 ml / 100 g or less, and even more preferably 135 ml / 100 g or less. If the DBP oil absorption exceeds 250 ml / 100 g, grip performance tends to decrease. The DBP oil absorption of carbon black in the present specification is a value measured according to JIS K6217-4: 2008.

  When carbon black is contained, the content of carbon black based on 100 parts by mass of the rubber component is preferably 50 parts by mass or more, more preferably 80 parts by mass or more, and even more preferably 100 parts by mass or more. When the content of carbon black is less than 50 parts by mass, there is a tendency that sufficient wear resistance and grip performance are not obtained, and the content of carbon black is preferably 200 parts by mass or less, and more preferably 150 parts by mass or less. Is more preferred. When the content of carbon black exceeds 200 parts by mass, grip performance tends to decrease.

  The zinc oxide is not particularly limited as long as it is used in the field of rubber such as tires, but it is preferable to use particulate zinc oxide.

  The average primary particle diameter of the particulate zinc oxide is preferably 200 nm or less, more preferably 100 nm or less. The lower limit of the average primary particle diameter of zinc oxide is not particularly limited, but is preferably 20 nm or more, and more preferably 30 nm or more. The average primary particle diameter of zinc oxide in the present specification is an average particle diameter (average primary particle diameter) converted from a specific surface area measured by a BET method using nitrogen adsorption.

  When zinc oxide is contained, the content of zinc oxide with respect to 100 parts by mass of the rubber component is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more. Further, the content of zinc oxide is preferably at most 10 parts by mass, more preferably at most 5 parts by mass. When the content of zinc oxide is within the above range, the effects of the present invention can be more suitably obtained.

  Examples of the vulcanization accelerator include sulfenamide, thiazole, thiuram, and guanidine vulcanization accelerators, and thiazole and thiuram vulcanization accelerators can be suitably used. Examples of the thiazole vulcanization accelerator include 2-mercaptobenzothiazole, cyclohexylamine salt of 2-mercaptobenzothiazole, di-2-benzothiazolyl disulfide, and the like. Zolyl disulfide is preferred. Examples of the thiuram-based vulcanization accelerator include tetramethylthiuram disulfide (TMTD), tetrabenzylthiuram disulfide (TBzTD), tetrakis (2-ethylhexyl) thiuram disulfide (TOT-N), and among others, TOT-N N is preferred.

  When the vulcanization accelerator is contained, the content of the vulcanization accelerator is preferably at least 1 part by mass, more preferably at least 3 parts by mass based on 100 parts by mass of the rubber component. When the content of the vulcanization accelerator is less than 1 part by mass, a sufficient vulcanization rate cannot be obtained, and good grip performance and abrasion resistance tend not to be obtained. Further, the content of the vulcanization accelerator is preferably 15 parts by mass or less, more preferably 10 parts by mass or less. When the content of the vulcanization accelerator exceeds 15 parts by mass, blooming occurs, and grip performance and abrasion resistance tend to decrease.

  As a method for producing the rubber composition according to the present invention, a known method can be used. For example, the rubber composition can be produced by kneading the above components with a Banbury mixer, a kneader, an open roll, or the like, and then vulcanizing. .

  The high performance tire of the present invention can be produced by a usual method using the rubber composition of the present invention. That is, a rubber composition obtained by compounding the above compounding agent with the rubber component as necessary is extruded according to the shape of the tread in an unvulcanized stage, and is pasted together with other tire members on a tire molding machine. Then, an unvulcanized tire is formed by molding in a usual manner, and the unvulcanized tire is heated and pressed in a vulcanizer, whereby the high-performance tire of the present invention can be manufactured. The high-performance tire according to the present invention can be suitably applied to racing tires and other high performance tires, particularly high-performance dry tires used on dry road surfaces.

  The present invention will be described based on examples, but the present invention is not limited to the examples.

Hereinafter, various chemicals used in Examples and Comparative Examples are collectively shown.
SBR: Toughden 4850 manufactured by Asahi Kasei Corporation (S-SBR, styrene content: 40% by mass, 50 parts by mass of oil component per 100 parts by mass of rubber solid content)
Carbon black: N219 manufactured by Cabot Japan Co., Ltd. (N ₂ SA: 106 m ² / g, DBP oil absorption: 78 ml / 100 g)
Oil: Diana Process AH-24 manufactured by Idemitsu Kosan Co., Ltd.
Liquid diene polymer: L-SBR-820 manufactured by Kuraray Co., Ltd. (liquid SBR, Mw: 10000)
Adhesive resin 1: Coumaron G-90 (Coumarone indene resin (low softening point resin), softening point: 90 ° C) manufactured by Nikki Chemical Co., Ltd.
Adhesive resin 2: TO125 (terpene resin (high softening point resin), softening point 125 ° C) manufactured by Yasuhara Chemical Co., Ltd.
Adhesive resin 3: Nisseki Neopolymer 170S manufactured by JX Nippon Oil & Energy Corporation (coumarone indene resin (high softening point resin), softening point: 160 ° C)
Adhesive resin 4: Sylvatraxx4401 manufactured by Arizona Chemical Co. (styrene resin (low softening point resin), softening point: 85 ° C)
Low-temperature plasticizer 1: DOS manufactured by Daihachi Chemical Industry Co., Ltd. (solidification point: -62 ° C, viscosity: 18 mPa · s (25 ° C))
Low temperature plasticizer 2: TOP manufactured by Daihachi Chemical Industry Co., Ltd. (freezing point: -70 ° C or less, viscosity: 12 mPa · s (25 ° C))
Zinc oxide: Jincock Super F-1 manufactured by Hakusuitec Co., Ltd. (average primary particle diameter: 100 nm)
Wax: Sannoc N manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
Anti-aging agent 1: Nocrack 6C (N- (1,3-dimethylbutyl) -N-phenyl-p-phenylenediamine, 6PPD, manufactured by Ouchi Shinko Chemical Co., Ltd.)
Anti-aging agent 2: Nocrack RD (poly (2,2,4-trimethyl-1,2-dihydroquinoline) manufactured by Ouchi Shinko Chemical Co., Ltd.)
Stearic acid: "Tsubaki" stearic acid manufactured by NOF Corporation
Sulfur: powder sulfur vulcanization accelerator manufactured by Tsurumi Chemical Co., Ltd. 1: Noxeller DM (di-2-benzothiazolyl disulfide) manufactured by Ouchi Shinko Chemical Industry Co., Ltd.
Vulcanization accelerator 2: Noxeller TOT-N (tetrakis (2-ethylhexyl) thiuram disulfide) manufactured by Ouchi Shinko Chemical Industry Co., Ltd.

Examples and Comparative Examples According to the composition shown in Tables 1 and 2, the above various chemicals (excluding sulfur and the vulcanization accelerator) were kneaded with a 1.7 L Banbury mixer at a discharge temperature of 140 ° C. for 20 minutes, and mixed. A paste was obtained. Sulfur and a vulcanization accelerator were added to the obtained kneaded material, and the mixture was kneaded using an open roll to obtain an unvulcanized rubber composition. The obtained unvulcanized rubber composition was molded into a tread shape, stuck together with other tire members on a tire molding machine, and vulcanized at 150 ° C. for 30 minutes to obtain a test tire (tire size: 215). / 45R17). The following evaluation was performed about the obtained test tire. Table 1 shows the results.

<Initial grip performance>
The test tires were mounted on all the wheels of a domestic FR car (2000 cc), and the vehicle traveled 10 times on a dry asphalt road surface test course. At this time, the test driver evaluated the stability of the control during the steering on the second lap. The larger the value, the higher the initial grip performance. Note that the initial grip performance index is set to 110 or more as the performance target index.

<Grip performance during running>
The test tires were mounted on all wheels of a domestic FR car (2000 cc), and the vehicle was run on the test course on dry asphalt road surface for 10 laps. At this time, the test driver compared and evaluated the stability of the control at the time of steering the best lap and the last lap, and displayed the index as Comparative Example 1 as 100. The larger the value, the smaller the decrease in grip performance during running on a dry road surface, indicating that stable grip performance during running can be better obtained. The grip performance index during running is set to 110 or more as the performance target index.

<Wear resistance>
The test tires were mounted on all wheels of a domestic FR car (2000 cc), and the vehicle was run on a dry asphalt road test course. The remaining groove amount of the tire tread rubber at that time was measured (15 mm at the time of a new product), and the remaining groove amount of Comparative Example 1 was set to 100 and indicated as an index. The higher the wear resistance index, the higher the wear resistance. The wear resistance index is set to 96 or more as the performance target index.

  From the results of Tables 1 and 2, the high performance tire having the tread composed of the rubber component and the rubber composition containing the predetermined amount of the pressure-sensitive adhesive resin and the softening agent containing the predetermined amount of the low-temperature plasticizer has a sufficient resistance It can be seen that the initial grip performance, especially on a dry road surface, and the stable grip performance during running can be simultaneously improved to a high degree while maintaining abrasion.

Claims (9)

A rubber composition containing a rubber component and a softening agent (however, based on 100 parts by mass of the rubber component, contains 5 parts by mass or more of high vinyl polybutadiene having a softening point of -50 ° C to 50 ° C and a vinyl bond content of 50% or more. a high-performance tire having a tread comprised of excluding compositions),
The softening agent contains 35 to 100 parts by mass of an adhesive resin, 10 to 50 parts by mass of a low-temperature plasticizer, and 20 to 80 parts by mass of a liquid diene polymer with respect to 100 parts by mass of the rubber component,
The liquid diene polymer, liquid styrene-butadiene copolymer, liquid isoprene polymer, and Ri der least one member selected from the group consisting of liquid styrene isoprene copolymer,
A high-performance tire in which the low-temperature plasticizer has a freezing point of -50C or lower . A rubber composition containing a rubber component and a softening agent (however, based on 100 parts by mass of the rubber component, contains 5 parts by mass or more of high vinyl polybutadiene having a softening point of -50 ° C to 50 ° C and a vinyl bond content of 50% or more. A high-performance tire having a composition and a softening point of 110 to 150 ° C and an OH value of at least 180 parts by mass of a phenolic resin (excluding a composition containing 10 parts by mass or more).
The softening agent contains 35 to 100 parts by mass of an adhesive resin, 10 to 50 parts by mass of a low-temperature plasticizer, and 20 to 80 parts by mass of a liquid diene polymer with respect to 100 parts by mass of the rubber component,
The liquid diene polymer, liquid styrene-butadiene copolymer, liquid isoprene polymer, and Ri der least one member selected from the group consisting of liquid styrene isoprene copolymer,
The high-performance tire according to claim 1 , wherein the low-temperature plasticizer has a freezing point of -50C or less . The high-performance tire according to claim 1 or 2, wherein the content of the pressure-sensitive adhesive resin in the softener is 25% by mass or more. The ratio of the content of the adhesive resin to the content of the low-temperature plasticizer (the content of the adhesive resin / the content of the low-temperature plasticizer) is from 1.0 to 3.0. High performance tires. The high-performance tire according to any one of claims 1 to 4, wherein the pressure-sensitive adhesive resin has a softening point of 60 to 170C. The adhesive resin is at least one selected from the group consisting of a phenolic resin, a coumarone indene resin, a terpene resin, a styrene resin, an acrylic resin, a rosin resin, and a dicyclopentadiene resin. A high-performance tire according to the item. The high-performance tire according to any one of claims 1 to 6, wherein the adhesive resin includes a resin having a softening point of 60 to 115 ° C and a resin having a softening point of 120 to 170 ° C. The high-performance tire according to any one of claims 1 to 7, wherein the rubber component includes a solution-polymerized styrene-butadiene rubber and / or a modified styrene-butadiene rubber. The high-performance tire according to any one of claims 1 to 8 , wherein the viscosity of the low-temperature plasticizer at 25 ° C is 30 mPa · s or less.