JPWO2019156093A1 - Rubber composition and tires - Google Patents

Abstract

An object of the present invention is to provide a rubber composition having low heat generation, excellent wear resistance and workability. In order to achieve the above object, the present invention comprises a rubber component containing a diene-based rubber, a filler, a compound represented by the following formula (I), and an antiaging agent containing a compound having a phenol group. It is characterized by including.

Description

The present invention relates to rubber compositions and tires.

In recent years, there has been an increasing demand for fuel efficiency of automobiles, and tires with low rolling resistance are required. Therefore, as a rubber composition used for tire treads and the like, a rubber composition having a low tan δ and excellent low heat generation is desired.

In conventional pneumatic tires, measures such as increasing the particle size of carbon black in the rubber composition and reducing the amount of carbon black blended can be considered for the purpose of achieving low heat generation. At the same time, there are problems that the wear resistance of the tread rubber is lowered and the fracture resistance such as the cut resistance and the chipping resistance of the rubber is lowered.

Therefore, it has been desired to develop a technique capable of improving low heat generation without deteriorating other physical properties such as wear resistance.
As one of these techniques, for example, Patent Document 1 describes carbon black and a specific hydrazide compound in an elastomer containing natural rubber for the purpose of improving the chemical interaction between the rubber component and carbon black. The rubber composition is disclosed.

Japanese Patent Publication No. 2014-501827

However, the technology disclosed in Patent Document 1 is not sufficiently low in heat generation, and further improvement in low heat generation is required in order to meet the demand for low fuel consumption of automobiles. In addition, when the low heat generation was improved by the technique of Patent Document 1, a polymer gel was formed in the rubber composition, and the workability was considered to be deteriorated (increased viscosity). Further improvement in sex was desired.

Therefore, an object of the present invention is to provide a rubber composition having excellent low heat generation, wear resistance and workability. Another object of the present invention is to provide a tire having low heat generation, wear resistance and excellent productivity.

The present inventors have conducted diligent research on a rubber composition containing a rubber component and a filler in order to solve the above-mentioned problems. Then, attention was paid to the fact that by incorporating a hydrazide compound having a specific structure in the rubber composition, the interaction between the rubber component and carbon black can be enhanced, and as a result, more excellent low heat generation can be realized. Regarding the problem of deterioration of processability caused by the formation of the polymer gel described above, by further containing an antiaging agent containing a compound having a phenol group in the rubber composition, excellent low heat generation and We have found that both wear resistance and excellent workability can be achieved, and have completed the present invention.

（式中、Ａは、アリール基であり、少なくとも２つの極性基を有し、該極性基は同じであっても、異なっていてもよい。Ｒ¹及びＲ²は、それぞれ独立して、水素原子、アシル基、アミド基、アルキル基、シクロアルキル基及びアリール基からなる群から選択される少なくとも一種の置換基であり、さらに、該置換基は、Ｏ、Ｓ及びＮ原子のうちの一種以上を含んでいてもよい。）
上記構成を具えることによって、優れた低発熱性、耐摩耗性及び加工性を実現できる。That is, the rubber composition of the present invention contains a rubber component containing a diene-based rubber, a filler, a compound represented by the following formula (I), and an antiaging agent containing a compound having a phenol group. It is characterized by including.

(In the formula, A is an aryl group and has at least two polar groups, the polar groups may be the same or different. R ¹ and R ² are independently hydrogen. It is at least one substituent selected from the group consisting of an atom, an acyl group, an amide group, an alkyl group, a cycloalkyl group and an aryl group, and the substituent is one or more of O, S and N atoms. May be included.)
By providing the above configuration, excellent low heat generation, wear resistance and workability can be realized.

Further, in the rubber composition of the present invention, at least one of the polar groups of A in the compound represented by the formula (I) is preferably a hydroxyl group, an amino group or a nitro group, and the polar group is preferable. It is more preferable that at least one of the polar groups is a hydroxyl group, and it is particularly preferable that at least two of the polar groups are hydroxyl groups. This is because better low heat generation and wear resistance can be realized.

Further, in the rubber composition of the present invention, it is preferable that A in the compound represented by the formula (I) is a phenyl group or a naphthyl group. This is because it is possible to realize better low heat generation and wear resistance, and it is also excellent in terms of practicality.

Further, in the rubber composition of the present invention, it is preferable that both R ¹ and R ² in the compound represented by the formula (I) are hydrogen atoms. This is because better low heat generation and wear resistance can be realized.

Further, in the rubber composition of the present invention, the molecular weight of the compound represented by the formula (I) is preferably 250 or less. This is because better low heat generation and wear resistance can be realized.

Furthermore, for the rubber composition of the present invention, the melting point of the compound represented by the formula (I) is preferably 80 ° C. or higher and lower than 250 ° C. This is because better low heat generation and wear resistance can be realized.

Further, in the rubber composition of the present invention, the content of the compound represented by the formula (I) is preferably 0.05 to 30 parts by mass with respect to 100 parts by mass of the rubber component. This is because better low heat generation and wear resistance can be realized, and deterioration of workability can be effectively suppressed.

Further, in the rubber composition of the present invention, the compounds represented by the formula (I) are 2,6-dihydroxybenzohydrazide, 2,3-dihydroxybenzohydrazide, 2,4-dihydroxybenzohydrazide, 2,5. -Dihydroxybenzohydrazide, 4-amino-2-hydroxybenzohydrazide, 3,5-dihydroxynaphthalene-2-carbhydrazide, 4-amino-3-hydroxynaphthalene-2-carbhydrazide, 3-hydroxy-4-nitronaphthalene- At least one selected from the group consisting of 2-carbohydrazide, 1,3-dihydroxynaphthalene-2-carbohydrazide, 2,4,6-trihydroxybenzohydrazide and 2,6-dihydroxy-4-methylbenzohydrazide. It is preferable to have. This is because better low heat generation and wear resistance can be realized.

Further, in the rubber composition of the present invention, it is preferable that the diene-based rubber is a natural rubber. This is because excellent wear resistance can be realized.

Further, in the rubber composition of the present invention, it is preferable that the filler contains carbon black. This is because excellent wear resistance can be realized.

Furthermore, in the rubber composition of the present invention, the content of the filler is preferably 10 to 160 parts by mass with respect to 100 parts by mass of the rubber component. This is because better low heat generation and wear resistance can be realized.

Further, in the rubber composition of the present invention, the ratio of the molecular weight of the compound having a phenol group to the number of phenol groups is preferably 250 or less. This is because better workability can be realized.

Further, in the rubber composition of the present invention, the total content of the anti-aging agent is preferably 0.05 to 10 parts by mass with respect to 100 parts by mass of the rubber component. This is because better workability can be realized without causing deterioration of viscosity.

Furthermore, in the rubber composition of the present invention, the proportion of the compound having a phenol group in the antiaging agent is preferably 20 to 100% by mass. This is because it is possible to realize better workability while obtaining an anti-aging effect.

Further, in the rubber composition of the present invention, the anti-aging agent further contains an amine-based anti-aging agent, and the proportion of the amine-based anti-aging agent in the anti-aging agent is 80% by mass or less. preferable. This is because deterioration of workability can be suppressed more reliably.

The tire of the present invention is characterized by using the above-mentioned rubber composition.
By providing the above configuration, excellent low heat generation, wear resistance and productivity can be realized.

According to the present invention, it is possible to provide a rubber composition having low heat generation, excellent wear resistance and workability. Further, according to the present invention, it is possible to provide a tire having low heat generation, excellent wear resistance and productivity.

（式中、Ａは、アリール基であり、少なくとも２つの極性基を有し、該極性基は同じであっても、異なっていてもよい。Ｒ¹及びＲ²は、それぞれ独立して、水素原子、アシル基、アミド基、アルキル基、シクロアルキル基及びアリール基からなる群から選択される少なくとも一種の置換基であり、さらに、該置換基は、Ｏ、Ｓ及びＮ原子のうちの一種以上を含んでいてもよい。）Hereinafter, embodiments of the present invention will be specifically illustrated.
<Rubber composition>
The rubber composition of the present invention is a rubber composition containing a rubber component, a filler, a compound represented by the following formula (I), and an antiaging agent containing a compound having a phenol group.

(In the formula, A is an aryl group and has at least two polar groups, the polar groups may be the same or different. R ¹ and R ² are independently hydrogen. It is at least one substituent selected from the group consisting of an atom, an acyl group, an amide group, an alkyl group, a cycloalkyl group and an aryl group, and the substituent is one or more of O, S and N atoms. May be included.)

(Rubber component)
The rubber component contained in the rubber composition of the present invention is not particularly limited as long as it contains a diene-based rubber.
Regarding the diene rubber, for example, natural rubber, polybutadiene rubber (BR), polyisoprene rubber (IR), styrene / butadiene copolymer rubber (SBR), styrene isoprene butadiene rubber (SIBR), chloroprene rubber (CR) , Synthetic diene rubber such as acrylonitrile butadiene rubber (NBR), and among these, it is preferable to contain at least natural rubber. This is because better low heat generation can be realized, and improvement in wear resistance can be expected.
The diene-based rubber may be contained alone or as a blend of two or more.

Regarding the rubber component, in addition to the above-mentioned diene rubber, non-diene rubber such as ethylene propylene diene rubber (EPDM), ethylene propylene rubber (EPM), and butyl rubber (IIR) are used as long as the effects of the invention are not impaired. It is also possible to include synthetic rubber.

The content of the diene rubber in the rubber component is not particularly limited, but is preferably 80% by mass or more, preferably 90% by mass, from the viewpoint of maintaining excellent low heat generation and wear resistance. More preferably, it is% or more.

(Filler)
The rubber composition of the present invention contains a filler in addition to the rubber components described above.
By including the filler together with the rubber component and the compound represented by the formula (I) described later, the dispersibility of the filler is enhanced, and excellent performance such as strength and wear resistance is maintained at a high level. Low heat generation can be realized.

Here, the content of the filler is not particularly limited, but is preferably 10 to 160 parts by mass, more preferably 30 to 100 parts by mass with respect to 100 parts by mass of the rubber component. preferable. This is because it is possible to realize better low heat generation and wear resistance by optimizing the amount of the filler, and when the content is 10 parts by mass or more, sufficient wear resistance can be obtained. When the content is 160 parts by mass or less, deterioration of low heat generation can be suppressed.

Further, the type of the filler is not particularly limited. For example, carbon black, silica, and other inorganic fillers can be included. Among them, the filler preferably contains carbon black. This is because better low heat generation can be realized, and improvement in wear resistance can be expected.
Here, examples of the carbon black include carbon blacks such as GPF, FEF, SRF, HAF, ISAF, IISAF, and SAF grade.

From the viewpoint of obtaining better wear resistance, the content of the carbon black is preferably 10 parts by mass or more, and more preferably 30 parts by mass or more with respect to 100 parts by mass of the rubber component. It is preferably 50 parts by mass or more, and more preferably 50 parts by mass or more. This is because the wear resistance of the rubber composition can be further improved by setting the content of the carbon black to 10 parts by mass or more with respect to 100 parts by mass of the rubber component. Further, the content of the carbon black is preferably 160 parts by mass or less, more preferably 90 parts by mass or less, and further preferably 70 parts by mass or less with respect to 100 parts by mass of the rubber component. preferable. By setting the content of the carbon black to 160 parts by mass or less with respect to 100 parts by mass of the rubber component, it is possible to further improve low heat generation and workability while maintaining a high level of wear resistance. ..

The silica as the filler is not particularly limited, and for example, wet silica, dry silica, colloidal silica and the like can be used.
Further, as the other inorganic filler, for example, an inorganic compound represented by the following formula (II) can be used.
nM ・ xSiO _Y・ zH ₂ O ・ ・ ・ (II)
(In the formula, M is a metal selected from the group consisting of Al, Mg, Ti, Ca and Zr, oxides or hydroxides of these metals, hydrates thereof, and carbonates of these metals. At least one selected from; n, x, y and z are integers 1-5, 0-10, 2-5, and 0-10, respectively.)

Examples of the inorganic compound of the above formula (II) include alumina (Al ₂ O ₃ ) such as γ-alumina and α-alumina; alumina monohydrate such as boehmite and diaspore (Al ₂ O ₃ · H ₂ O); , Aluminum hydroxide [Al (OH) ₃ ] such as Bayalite; Aluminum carbonate [Al ₂ (CO ₃ ) ₃ ], Magnesium hydroxide [Mg (OH) ₂ ], Magnesium oxide (MgO), Magnesium carbonate (MgCO ₃₎ ), talc _{(3MgO · 4SiO 2 · H 2} O), attapulgite _{(5MgO · 8SiO 2 · 9H 2} O), titanium white (TiO _2), titanium black (TiO _2n-1), calcium oxide (CaO), hydroxide calcium [Ca (OH) _2], magnesium aluminum oxide _{(MgO · Al 2 O 3)} , clay _{(Al 2 O 3 · 2SiO 2} ), kaolin _{(Al 2 O 3 · 2SiO 2} · 2H 2 O), pyrophyllite _{(Al 2 O 3 · 4SiO 2} · H 2 O), bentonite _{(Al 2 O 3 · 4SiO 2} · 2H 2 O), aluminum silicate _{(Al 2 SiO 5, Al 4} · 3SiO 4 · 5H 2 O , etc.), Magnesium silicate (Mg ₂ SiO ₄ , MgSiO ₃ etc.), Calcium silicate (Ca ₂ SiO ₄ etc.), Aluminum oxide calcium silicate (Al ₂ O ₃ · CaO · 2SiO ₂ etc.), Magnesium magnesium silicate (CaMgSiO _{4 etc.} ) , Calcium carbonate (CaCO ₃ ), zirconium oxide (ZrO ₂ ), zirconium hydroxide [ZrO (OH) ₂ · nH ₂ O], zirconium carbonate [Zr (CO ₃ ) ₂ ], corrects charge like various zeolites Crystalline aluminosilicates containing hydrogen, alkali metals or alkaline earth metals and the like can be mentioned.

式（Ｉ）の、Ａは、アリール基である。ここで、該アリール基は、任意の位置に少なくとも２つの極性基を有し、該極性基は同じであっても、異なっていてもよく、前記極性基の位置については、アリール基の芳香環中のどこであってもよい。
また、式（Ｉ）のＲ¹及びＲ²は、それぞれ独立して、水素原子、アシル基、アミド基、アルキル基、シクロアルキル基及びアリール基からなる群から選択される少なくとも一種の置換基である。さらに、これらの置換基については、Ｏ、Ｓ及びＮ原子のうちの一種以上を含んでいてもよい。(Compound represented by formula (I))
The rubber composition of the present invention contains the compound represented by the formula (I) in addition to the rubber component and the filler described above.

In formula (I), A is an aryl group. Here, the aryl group has at least two polar groups at arbitrary positions, and the polar groups may be the same or different, and the positions of the polar groups are the aromatic rings of the aryl groups. It can be anywhere inside.
Further, R ¹ and R ² of the formula (I) are independently at least one substituent selected from the group consisting of a hydrogen atom, an acyl group, an amide group, an alkyl group, a cycloalkyl group and an aryl group. is there. Further, these substituents may contain one or more of O, S and N atoms.

For the compound represented by the above formula (I), the aryl group represented by A has a high affinity with a filler such as carbon black, and the portion having a hydrazide skeleton has a high affinity with the rubber component. Therefore, by blending it in the rubber composition, the chemical interaction between the rubber component and the filler can be greatly improved. As a result, the hysteresis loss caused by the rubbing of the fillers can be reduced, and as a result, extremely excellent low heat generation can be obtained as compared with the conventional case. In addition, by improving the dispersibility of the filler, better wear resistance can be realized.
Further, as a result of greatly improving the chemical interaction between the rubber component and the filler, it is possible to suppress an increase in the viscosity of the unvulcanized rubber while maintaining low heat generation and wear resistance of the rubber composition. Can also be improved.

Here, examples of the aryl group represented by A in the compound represented by the formula (I) include aromatic hydrocarbon groups such as a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, and a triphenylenyl group. Among them, the aryl group is preferably a phenyl group or a naphthyl group, and more preferably a phenyl group. Since it exhibits an affinity with an excellent filler, it is possible to realize better low heat generation and wear resistance, and since the number of aromatic rings can be reduced, it is advantageous in terms of cost and practicality.

Further, the number of polar groups contained in the aryl group represented by A in the compound represented by the formula (I) is two or more. This is because having two or more polar groups in the aromatic ring makes it possible to obtain a high affinity with a filler such as carbon black, and when the number is less than two, the affinity with the filler is sufficient. However, the low heat generation and wear resistance of the rubber composition may be lowered.
The type of the polar group is not particularly limited, and for example, an amino group, an imino group, a nitrile group, an ammonium group, an imide group, an amide group, a hydrazo group, an azo group, a diazo group, a hydroxyl group and a carboxy group. , Carbonyl group, epoxy group, oxycarbonyl group, nitrogen-containing heterocyclic group, oxygen-containing heterocyclic group, tin-containing group, alkoxysilyl group, alkylamino group, nitro group and the like. Among them, at least one of the polar groups is preferably a hydroxyl group, an amino group or a nitro group, more preferably a hydroxyl group, and particularly preferably at least two hydroxyl groups. This is because it exhibits an excellent affinity with the filler and can further improve the low heat generation and wear resistance of the rubber composition.

Regarding the hydrazide group connected to A in the compound represented by the above formula (I), R ¹ and R ² are independently hydrogen atoms, acyl groups, amide groups, alkyl groups, cycloalkyl groups and aryls, respectively. It is at least one substituent selected from the group consisting of groups. In addition, these substituents may contain one or more of O, S and N atoms.
Further, R ¹ and R ² are preferably hydrogen atoms or alkyl groups among the above-mentioned substituents, and more preferably both R ¹ and R ² are hydrogen atoms. This is because it has a high affinity with the rubber component, and more excellent low heat generation, wear resistance and workability can be obtained.

２，３−ジヒドロキシベンゾヒドラジド

２，４−ジヒドロキシベンゾヒドラジド

２，５−ジヒドロキシベンゾヒドラジド

４−アミノ−２−ヒドロキシベンゾヒドラジド

３，５−ジヒドロキシナフタレン−２−カルボヒドラジド

４−アミノ−３−ヒドロキシナフタレン−２−カルボヒドラジド

３−ヒドロキシ−４−ニトロナフタレン−２−カルボヒドラジド

１，３−ジヒドロキシナフタレン−２−カルボヒドラジド

２，４，６−トリヒドロキシベンゾヒドラジド

２，６−ジヒドロキシ−４−メチルベンゾヒドラジド

Here, some suitable examples of the compound represented by the above-mentioned formula (I) are shown below. By using these compounds, the low heat generation property of the rubber composition can be further improved. It should be noted that these compounds may be used alone or in combination of two or more.
2,6-dihydroxybenzohydrazide

2,3-Dihydroxybenzohydrazide

2,4-Dihydroxybenzohydrazide

2,5-dihydroxybenzohydrazide

4-Amino-2-hydroxybenzohydrazide

3,5-Dihydroxynaphthalene-2-carbohydrazide

4-Amino-3-hydroxynaphthalene-2-carbohydrazide

3-Hydroxy-4-nitronaphthalene-2-carbohydrazide

1,3-Dihydroxynaphthalene-2-carbohydrazide

2,4,6-trihydroxybenzohydrazide

2,6-dihydroxy-4-methylbenzohydrazide

The molecular weight of the compound represented by the formula (I) is preferably 250 or less, more preferably 200 or less, and even more preferably 180 or less. This is because the affinity of the natural rubber with each molecule is increased, more excellent low heat generation can be obtained, and the wear resistance can be improved.

The melting point of the compound represented by the formula (I) is preferably 80 ° C. or higher and lower than 250 ° C., more preferably 80 to 200 ° C. This is because by lowering the melting point of the hydrazide compound, the affinity with each molecule of the natural rubber is increased, more excellent low heat generation property can be obtained, and the abrasion resistance can also be improved.

The content of the compound represented by the formula (I) in the rubber composition of the present invention is preferably 0.05 to 30 parts by mass with respect to 100 parts by mass of the rubber component, preferably 0.05. It is more preferably 10 parts by mass, and particularly preferably 0.05 to 5 parts by mass. When the content is 0.05 parts by mass or more with respect to 100 parts by mass of the rubber component, more excellent low heat generation and wear resistance can be obtained, and when it is 30 parts by mass or less, the processability is improved. This is because deterioration can be prevented.

(Anti-aging agent)
The rubber composition of the present invention further contains an anti-aging agent in addition to the above-mentioned rubber component, filler and compound represented by the formula (I). The anti-aging agent is required to contain a compound having a phenol group (hereinafter, may be referred to as a "phenol group-containing compound").
By including the compound represented by the formula (I), it has become possible to greatly improve the chemical interaction between the rubber component and the filler, but along with this, a polymer gel is generated and the processability is improved. It was thought to get worse. Therefore, in the present invention, by using a phenol group-containing compound as an antiaging agent in the rubber composition, it is possible to improve the processability while maintaining the low heat generation at an excellent level.

Here, the type of the phenol group-containing compound is not particularly limited, and can be appropriately selected and used from known antioxidants.
Examples of the phenol group-containing compound include monophenolic compounds, bisphenolic compounds, thiobisphenolic compounds, hindered phenolic compounds, and polyphenolic compounds.

Regarding the phenol group-containing compound, among the above-mentioned compounds, the ratio of the molecular weight to the number of phenol groups (molecular weight / number of phenol groups) is preferably 250 or less, more preferably 200 or less. .. This is because better workability can be obtained. Regarding the number of phenol groups in the phenol group-containing compound, in the case of a compound (hydroquinone or the like) in which two phenol groups are bonded to one benzene ring, it is assumed that the compound has two phenol groups.
In addition, among the phenol group-containing compounds having a molecular weight ratio of 250 or less to the number of phenol groups, 2,2'-methylenebis (4-methyl-6-tert) can provide even better processability. -Butylphenol), 4,4'-butylidenebis (3-methyl-6-tert-butylphenol), 2,6-di-tert-butyl-4-methylphenol, 2,5-di-tert-amylhydroquinone, 2, 5-Di-tert-butylhydroquinone, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-thiobis (3-methyl-6-tert-butylphenol), 2,6 di-tert-butyl-4 More preferably, it contains at least one selected from the group consisting of -ethylphenol and bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide.

Further, the proportion of the phenol group-containing compound in the antioxidant is preferably 20 to 100% by mass, more preferably 20 to 80% by mass. By setting the proportion of the phenol group-containing compound to 20% by mass or more, deterioration of processability of the rubber composition can be suppressed. Further, although it can be composed of only the phenol group-containing compound, when it is 80% by mass or less, an antiaging effect can be more reliably obtained.

The anti-aging agent may contain an anti-aging agent other than the phenol group-containing compound for the purpose of improving the anti-aging effect, etc., as long as the effects of the present invention are not impaired. For example, an amine-based anti-aging agent can be further contained. In that case, the content of the amine-based anti-aging agent in the anti-aging agent is preferably 80% by mass or less, and more preferably 60% by mass or less. This is because by setting the content of the amine-based anti-aging agent in the anti-aging agent to 80% by mass or less, deterioration of processability of the rubber composition can be suppressed.

The total content of the anti-aging agent in the rubber composition of the present invention is preferably 0.05 to 10 parts by mass, and 0.05 to 5 parts by mass with respect to 100 parts by mass of the rubber component. Is more preferable. By setting the total content of the anti-aging agent to 0.05 parts by mass or more with respect to 100 parts by mass of the rubber component, the anti-aging effect can be obtained more reliably, and the content of the anti-aging agent can be adjusted. By setting the amount to 10 parts by mass or less with respect to 100 parts by mass of the rubber component, deterioration of workability can be suppressed.

(Other ingredients)
The rubber composition of the present invention is commonly used in the rubber industry in addition to the anti-aging agent containing the rubber component, the filler, the compound represented by the formula (I) and the compound having a phenol group. A compounding agent, for example, a softening agent, a silane coupling agent, zinc oxide, a vulcanization accelerator, a vulcanizing agent and the like can be appropriately selected and contained within a range that does not impair the object of the present invention. Commercially available products can be preferably used as these compounding agents.

The method for producing the rubber composition of the present invention is not particularly limited. For example, it can be obtained by blending a rubber component containing a diene-based rubber, a filler, a compound represented by the formula (I), and an antiaging agent by a known method and kneading them.

<Tire>
The tire of the present invention is characterized by using the rubber composition of the present invention described above. By including the rubber composition of the present invention having excellent low heat generation and workability as a tire material, excellent low heat generation and productivity can be realized.
The part to which the rubber composition is applied is preferably used for the tread in the tire. A tire using the rubber composition of the present invention for a tread is excellent in low heat generation.
The tire of the present invention is not particularly limited except that the rubber composition of the present invention described above is used for any of the tire members, and can be produced according to a conventional method. As the gas to be filled in the tire, an inert gas such as nitrogen, argon, or helium can be used in addition to normal or adjusted oxygen partial pressure.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples.

(Compounds a to k)
Compounds a to k were produced. The types of compounds a to k, melting points, and ¹ H-NMR measurement results (conditions: 300 MHz, DMSO-d ₆ , δ ppm) are shown below.

（融点：１９８℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：６．３（ｄ，２Ｈ），７．１（ｔ，１Ｈ），ＮＨ（３Ｈ）及びＯＨ（２Ｈ）は不検出）

・化合物ｂ：２，３−ジヒドロキシベンゾヒドラジド
２，３−ジヒドロキシ安息香酸メチル２．７５ｇ、１００％ヒドラジン一水和物７．００ｇを水１．５ｍLに添加し、１００℃で３時間攪拌した。反応液を濃縮後、析出している固体にイソプロピルアルコールを加えて濾過し、イソプロピルアルコールで洗浄した。得られた固体を減圧乾燥し、淡黄色固体２，３−ジヒドロキシベンゾヒドラジド２．００ｇ（収率７３％）を得た。

（融点：２２３℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：４．７（ｂｒ−ｓ，２Ｈ），６．７（ｍ，１Ｈ）， ６．９（ｍ，１Ｈ），７．２（ｍ，１Ｈ），１０．１（ｂｒ−ｓ，１Ｈ），ＯＨ（２Ｈ）は不検出）

・化合物ｃ：２，４−ジヒドロキシベンゾヒドラジド
２，４−ジヒドロキシ安息香酸メチル５．５０ｇ、１００％ヒドラジン一水和物１３．４ｇを水３ｍＬに添加し、１００℃で３時間攪拌した。反応液を濃縮後、析出している固体にイソプロピルアルコールを加えて濾別し、イソプロピルアルコールで洗浄した。得られた固体を減圧乾燥し、淡黄色固体２，４−ジヒドロキシベンゾヒドラジド４．８２ｇ（収率８８％）を得た。

（融点：２３７℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
６．２（ｍ，２Ｈ），７．６（ｍ，１Ｈ），ＮＨ（３Ｈ）及びＯＨ（２Ｈ）は不検出）

・化合物ｄ：２，５−ジヒドロキシベンゾヒドラジド
２，５−ジヒドロキシ安息香酸メチル５．３９ｇ、１００％ヒドラジン一水和物３．２９ｇを１−ブタノール３２ｍＬに添加し、１１７℃で１５時間攪拌した。反応液を冷却後、析出している固体を濾別し、イソプロピルアルコールで洗浄した。得られた固体を減圧乾燥し、淡黄色固体２，５−ジヒドロキシベンゾヒドラジド４．２６ｇ（収率７９％）を得た。

（融点：２１０℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：４．６（ｂｒ−ｓ，２Ｈ），６．７（ｍ，１Ｈ）， ６．８（ｍ，１Ｈ），７．２（ｍ，１Ｈ），９．０（ｂｒ−ｓ，１Ｈ），９．９（ｂｒ−ｓ，１Ｈ），１１．５（ｂｒ−ｓ，１Ｈ））

・化合物ｅ：４−アミノ−２−ヒドロキシベンゾヒドラジド
４−アミノ−２−ヒドロキシ安息香酸メチル１２．０ｇ、１００％ヒドラジン一水和物３０．３ｇを水６．６ｍＬに添加し、１００℃で２時間攪拌した。反応液を濃縮後、水を加え、析出した固体を濾別し、水で洗浄した。得られた固体を減圧乾燥し、淡黄色固体４−アミノ−２−ヒドロキシベンゾヒドラジド８．６８ｇ（収率７２％）を得た。

（融点：１９８℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
４．４（ｂｒ−ｓ，２Ｈ），５．７（ｍ，２Ｈ），６．０（ｍ，２Ｈ）， ７．４（ｍ，１Ｈ），９．５（ｍ，１Ｈ），１２．７（ｂｒ−ｓ，１Ｈ））

・化合物ｆ：３，５−ジヒドロキシナフタレン−２−カルボヒドラジド
３，５−ジヒドロキシナフトエ酸４３．０ｇ、濃硫酸４２．０ｍＬをメタノール８６０ｍＬに添加し、６５℃で４４時間攪拌した。反応液を冷却後、水を加え、析出した固体を濾別し、水で洗浄した。得られた固体を減圧乾燥し、淡黄色固体３，５−ジヒドロキシナフタレン−２−カルボン酸メチル４４．７ｇ（収率９７％）を得た。
上記の方法で得た３，５−ジヒドロキシナフタレン−２−カルボン酸メチル８．３９ｇ、１００％ヒドラジン一水和物５．２９ｇをブタノール４０．０ｍＬに添加し、６５℃で２時間攪拌した。反応液を濃縮し、析出した固体をイソプロピルアルコールに懸濁した。析出した固体を濾別し、イソプロピルエーテルで洗浄した。得られた固体を減圧乾燥し、淡黄色固体３，５−ジヒドロキシナフタレン−２−カルボヒドラジド５．０１ｇ（収率６０％）を得た。

（融点：２１９℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
６．８（ｍ，１Ｈ），７．１（ｍ，１Ｈ），７．３（ｍ，１Ｈ）， ７．４（ｓ，１Ｈ），８．３（ｓ，１Ｈ），１０．３（ｂｒ−ｓ，２Ｈ），ＮＨ（３Ｈ）不検出）

・化合物ｇ：４−アミノ−３−ヒドロキシナフタレン−２−カルボヒドラジド
３−ヒドロキシ−２−ナフトエ酸５０．０ｇをクロロホルム２７０ｍＬに加え、氷冷後、６０％硝酸２４．３ｍＬを滴下した。３５分間攪拌した後、析出した固体を濾別し、水、クロロホルムで洗浄した。得られた固体を減圧乾燥し、橙色固体３−ヒドロキシ−４−ニトロ−２−ナフトエ酸４７．７ｇ（収率７７％）を得た。
上記の方法で得た３−ヒドロキシ−４−ニトロ−２−ナフトエ酸１２．５ｇ、濃硫酸１ｍＬをブタノール２００ｍＬに添加し、１１７℃で４８時間攪拌した。反応液を濃縮後、析出している固体を濾別し、ブタノールで洗浄した。得られた固体を減圧乾燥し、黄色固体３−ヒドロキシ−４−ニトロナフタレン−２−カルボン酸ブチル７．５２ｇ（収率４８％）を得た。
上記の方法で得た３−ヒドロキシ−４−ニトロナフタレン−２−カルボン酸ブチル２８．７ｇ、パラジウムカーボン２．９０ｇをメタノール４９４ｍＬに添加し、水素で置換して室温で８時間攪拌した。反応液を濃縮後、得られた固体にヒドラジン一水和物１７．７ｇ、ブタノール３３０ｍＬを加え、７５℃で１３時間攪拌した。反応液を冷却後、析出している固体を濾別し、ブタノールで洗浄した。得られた固体を減圧乾燥し、淡黄色固体４−アミノ−３−ヒドロキシナフタレン−２−カルボヒドラジド２１．１ｇ（収率９８％）を得た。

（融点：１８１℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
４．７（ｂｒ−ｓ，２Ｈ），７．３（ｍ，１Ｈ）， ７，４（ｍ，１Ｈ），７．６（ｍ，１Ｈ），７．７（ｓ，１Ｈ），８．０（ｍ，１Ｈ），１０．４（ｂｒ−ｓ，１Ｈ），ＮＨ（３Ｈ）不検出）

・化合物ｈ：３−ヒドロキシ−４−ニトロナフタレン−２−カルボヒドラジド
３−ヒドロキシ−２−ナフトエ酸５０．０ｇをクロロホルム２７０ｍＬに加え、氷冷後、６０％硝酸２４．３ｍＬを滴下した。３５分間攪拌した後、固体を濾別し、水、クロロホルムで洗浄した。得られた固体を減圧乾燥し、橙色固体３−ヒドロキシ−４−ニトロ−２−ナフトエ酸４７．７ｇ（収率７７％）を得た。
上記の方法で得た３−ヒドロキシ−４−ニトロ−２−ナフトエ酸１２．５ｇ、濃硫酸１ｍＬをブタノール２００ｍＬに添加し、１１７℃で４８時間攪拌した。反応液を濃縮後、析出した固体を濾別し、ブタノールで洗浄した。得られた固体を減圧乾燥し、黄色固体３−ヒドロキシ−４−ニトロナフタレン−２−カルボン酸ブチル７．５２ｇ（収率４８％）を得た。
上記の方法で得た３−ヒドロキシ−４−ニトロナフタレン−２−カルボン酸ブチル１７．１ｇをメタノール１７５ｍＬに溶解し、１００％ヒドラジン一水和物６．２８ｇを添加し、６５℃で１６時間攪拌した。反応液を冷却後、析出した固体を濾別し、メタノールで洗浄した。得られた固体を減圧乾燥し、橙色固体３−ヒドロキシ−４−ニトロナフタレン−２−カルボヒドラジド１４．６ｇ（収率１００％）を得た。

（融点：１８５℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
７．１（ｍ，１Ｈ）， ７．４（ｍ，２Ｈ），７．８（ｍ，１Ｈ），８．４（ｍ，１Ｈ），ＮＨ（３Ｈ），ＯＨ（１Ｈ）不検出）

・化合物ｉ：１，３−ジヒドロキシナフタレン−２−カルボヒドラジド
マロン酸ジエチル５．００ｇのアセトニトリル５０ｍＬ溶液に塩化マグネシウム２．９７ｇを加え、氷冷した。次に、トリエチルアミン６．３０ｇを滴下して３０分間攪拌した後、フェニル酢酸クロリド４．８２ｇを滴下し、室温に戻し、４．５時間攪拌した。再び反応液を氷冷し、２Ｎ塩酸２００ｍＬを加え、酢酸エチルで抽出し、有機層を飽和食塩水で洗浄した。無水硫酸マグネシウムで乾燥し、濃縮後、減圧乾燥した。得られた淡黄色油状物残渣を氷冷し、濃硫酸１５ｍＬを滴下し、室温に戻して１７時間攪拌した。反応液を氷冷し、氷水３５ｍＬをゆっくり加え、析出した固体を濾別し、水洗した。得られた固体を減圧乾燥し、黄色固体１，３−ジヒドロキシナフタレン−２−カルボン酸エチル６．０９ｇ（収率８４％）を得た。
上記の方法で得た１，３−ジヒドロキシナフタレン−２−カルボン酸エチル８００ｍｇのメタノール３ｍＬ溶液に室温で１００％ヒドラジン一水和物０．２１ｇを加え、２．５時間加熱還流し、室温に戻して１２時間攪拌した。析出した固体を濾別し、得られた固体をメタノールで洗浄し、減圧乾燥して黄土色固体１，３−ジヒドロキシナフタレン−２−カルボヒドラジド５４０ｍｇ（収率７２％）を得た。

（融点：２０５℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
６．６（ｓ，１Ｈ）， ７．２（ｍ，１Ｈ），７．４（ｍ，１Ｈ），７．５（ｄ，１Ｈ），８．０（ｄ，１Ｈ），ＮＨ（３Ｈ），ＯＨ（２Ｈ）不検出）

・化合物ｊ：２，４，６−トリヒドロキシベンゾヒドラジド
２，４，６−トリヒドロキシ安息香酸１水和物１０．０ｇのアセトン１００ｍＬ溶液に、室温で炭酸ナトリウム２．９６ｇを加えて１０分間攪拌し、ジメチル硫酸７．０４ｇを加えて５０℃に昇温し、５時間攪拌した。反応液を濃縮し、水を加えて酢酸エチルで抽出し、有機層を飽和食塩水で洗浄した。更に無水硫酸マグネシウムで乾燥し、濃縮後、析出した固体を酢酸エチルとヘキサンの混合溶媒に懸濁して濾別し、減圧乾燥してピンク色固体２，４，６−トリヒドロキシ安息香酸メチル６．０３ｇ（収率６２％）を得た。
上記の方法で得た２，４，６−トリヒドロキシ安息香酸メチル２．４０ｇをメタノール１０ｍＬに懸濁させ、室温で１００％ヒドラジン一水和物０．９８ｇを加え、１．５時間加熱還流し、室温に戻して１２時間攪拌した。析出した固体を濾別し、得られた固体をメタノールで洗浄し、減圧乾燥してベージュ色固体２，４，６−トリヒドロキシベンゾヒドラジド９６０ｍｇ（収率４０％）を得た。

（融点：２０７℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
４．３（ｂｒ−ｓ，２Ｈ），５．８（ｓ，２Ｈ），７．２（ｓ，１Ｈ），９．３（ｂｒ−ｓ，１Ｈ），１２．３（ｂｒ−ｓ，２Ｈ））

・化合物ｋ：２，６−ジヒドロキシ−４−メチルベンゾヒドラジド
２，６−ジヒドロキシ−４−メチル安息香酸５．００ｇのアセトン５０ｍＬ溶液に、室温で炭酸ナトリウム１．６６ｇを加えて１０分間攪拌し、ジメチル硫酸３．９４ｇを加えて５０℃に昇温し、５時間攪拌した。反応液を濃縮し、水を加えて酢酸エチルで抽出し、有機層を飽和食塩水で洗浄した。更に無水硫酸マグネシウムで乾燥し、濃縮後、析出した固体を冷ヘキサンに懸濁して濾別し、減圧乾燥して白色固体２，６−ジヒドロキシ−４−メチル安息香酸メチル４．９４ｇ（収率９１％）を得た。
上記の方法で得た２，６−ジヒドロキシ−４−メチル安息香酸メチル４．５０ｇをメタノール１２ｍＬに懸濁させ、室温で１００％ヒドラジン一水和物１．８５ｇを加え、１２時間加熱還流した。室温に戻し、析出した固体を濾別し、得られた固体をメタノールで洗浄し、減圧乾燥してピンク色固体２，６−ジヒドロキシ−４−メチルベンゾヒドラジド３．０９ｇ（収率６９％）を得た。

（融点：１８０℃、¹Ｈ−ＮＭＲ（３００ＭＨｚ，ＤＭＳＯ−ｄ₆，δｐｐｍ）：
２．１４（ｓ，３Ｈ），５．１（ｂｒ−ｓ，２Ｈ），６．１（ｓ，２Ｈ），９．９（ｂｒ−ｓ，１Ｈ），１２．５（ｂｒ−ｓ，２Ｈ））Compound a: 5.29 g of methyl 2,6-dihydroxybenzoate and 3.30 g of 100% hydrazine monohydrate were added to 32 mL of 1-butanol and stirred at 117 ° C. for 15 hours. After cooling the reaction solution, the precipitated solid was filtered and washed with isopropyl alcohol. The obtained solid was dried under reduced pressure to obtain 2.85 g (yield 54%) of a pale yellow solid 2,6-dihydroxybenzohydrazide.

(Melting point: 198 ° C., ¹ H-NMR (300 MHz, DMSO-d ₆ , δ ppm): 6.3 (d, 2H), 7.1 (t, 1H), NH (3H) and OH (2H) are not present. detection)

Compound b: 2.75 g of methyl 2,3-dihydroxybenzoate and 7.00 g of 100% hydrazine monohydrate were added to 1.5 mL of water and stirred at 100 ° C. for 3 hours. After concentrating the reaction solution, isopropyl alcohol was added to the precipitated solid, the mixture was filtered, and the mixture was washed with isopropyl alcohol. The obtained solid was dried under reduced pressure to obtain 2.00 g (yield 73%) of a pale yellow solid 2,3-dihydroxybenzohydrazide.

(Melting point: 223 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm): 4.7 (br-s, 2H), 6.7 (m, 1H), 6.9 (m, 1H), 7.2 (m, 1H), 10.1 (br-s, 1H), OH (2H) are not detected)

Compound c: 5.50 g of methyl 2,4-dihydroxybenzoate and 13.4 g of 100% hydrazine monohydrate were added to 3 mL of water and stirred at 100 ° C. for 3 hours. After concentrating the reaction solution, isopropyl alcohol was added to the precipitated solid, the mixture was filtered off, and washed with isopropyl alcohol. The obtained solid was dried under reduced pressure to obtain 4.82 g (yield 88%) of a pale yellow solid 2,4-dihydroxybenzohydrazide.

(Melting point: 237 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
6.2 (m, 2H), 7.6 (m, 1H), NH (3H) and OH (2H) are not detected)

Compound d: 5.39 g of methyl 2,5-dihydroxybenzoic acid and 3.29 g of 100% hydrazine monohydrate were added to 32 mL of 1-butanol and stirred at 117 ° C. for 15 hours. After cooling the reaction solution, the precipitated solid was separated by filtration and washed with isopropyl alcohol. The obtained solid was dried under reduced pressure to obtain 4.26 g (yield 79%) of a pale yellow solid 2,5-dihydroxybenzohydrazide.

(Melting point: 210 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm): 4.6 (br-s, 2H), 6.7 (m, 1H), 6.8 (m, 1H), 7.2 (m, 1H), 9.0 (br-s, 1H), 9.9 (br-s, 1H), 11.5 (br-s, 1H))

Compound e: 4-amino-2-hydroxybenzohydrazide 12.0 g of methyl 4-amino-2-hydroxybenzoate and 30.3 g of 100% hydrazine monohydrate were added to 6.6 mL of water, and 2 at 100 ° C. Stirred for hours. After concentrating the reaction solution, water was added, and the precipitated solid was separated by filtration and washed with water. The obtained solid was dried under reduced pressure to obtain 8.68 g (yield 72%) of a pale yellow solid 4-amino-2-hydroxybenzohydrazide.

(Melting point: 198 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
4.4 (br-s, 2H), 5.7 (m, 2H), 6.0 (m, 2H), 7.4 (m, 1H), 9.5 (m, 1H), 12.7 (Br-s, 1H))

Compound f: 3,5-dihydroxynaphthalene-2-carbohydrazide 3,5-dihydroxynaphthal acid (43.0 g) and concentrated sulfuric acid (42.0 mL) were added to 860 mL of methanol, and the mixture was stirred at 65 ° C. for 44 hours. After cooling the reaction solution, water was added, and the precipitated solid was separated by filtration and washed with water. The obtained solid was dried under reduced pressure to obtain 44.7 g (yield 97%) of methyl 3,5-dihydroxynaphthalene-2-carboxylate as a pale yellow solid.
8.39 g of methyl 3,5-dihydroxynaphthalene-2-carboxylate and 5.29 g of 100% hydrazine monohydrate obtained by the above method were added to 40.0 mL of butanol, and the mixture was stirred at 65 ° C. for 2 hours. The reaction solution was concentrated, and the precipitated solid was suspended in isopropyl alcohol. The precipitated solid was filtered off and washed with isopropyl ether. The obtained solid was dried under reduced pressure to obtain 5.01 g (yield 60%) of a pale yellow solid 3,5-dihydroxynaphthalene-2-carbohydrazide.

(Melting point: 219 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
6.8 (m, 1H), 7.1 (m, 1H), 7.3 (m, 1H), 7.4 (s, 1H), 8.3 (s, 1H), 10.3 (br) −S, 2H), NH (3H) not detected)

-Compound g: 4-amino-3-hydroxynaphthalene-2-carbohydrazide 3-hydroxy-2-naphthoic acid 50.0 g was added to 270 mL of chloroform, and after ice cooling, 24.3 mL of 60% nitric acid was added dropwise. After stirring for 35 minutes, the precipitated solid was separated by filtration and washed with water and chloroform. The obtained solid was dried under reduced pressure to obtain 47.7 g (yield 77%) of an orange solid 3-hydroxy-4-nitro-2-naphthoic acid.
12.5 g of 3-hydroxy-4-nitro-2-naphthoic acid obtained by the above method and 1 mL of concentrated sulfuric acid were added to 200 mL of butanol, and the mixture was stirred at 117 ° C. for 48 hours. After concentrating the reaction solution, the precipitated solid was separated by filtration and washed with butanol. The obtained solid was dried under reduced pressure to obtain 7.52 g (yield 48%) of butyl 3-hydroxy-4-nitronaphthalene-2-carboxylate as a yellow solid.
28.7 g of butyl 3-hydroxy-4-nitronaphthalene-2-carboxylate and 2.90 g of palladium carbon obtained by the above method were added to 494 mL of methanol, replaced with hydrogen, and stirred at room temperature for 8 hours. After concentrating the reaction solution, 17.7 g of hydrazine monohydrate and 330 mL of butanol were added to the obtained solid, and the mixture was stirred at 75 ° C. for 13 hours. After cooling the reaction solution, the precipitated solid was separated by filtration and washed with butanol. The obtained solid was dried under reduced pressure to obtain 21.1 g (yield 98%) of a pale yellow solid 4-amino-3-hydroxynaphthalene-2-carbhydrazide.

(Melting point: 181 ° C, ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
4.7 (br-s, 2H), 7.3 (m, 1H), 7,4 (m, 1H), 7.6 (m, 1H), 7.7 (s, 1H), 8.0 (M, 1H), 10.4 (br-s, 1H), NH (3H) not detected)

-Compound h: 3-Hydroxy-4-nitronaphthalene-2-carbohydrazide 3-Hydroxy-2-naphthoic acid 50.0 g was added to 270 mL of chloroform, and after ice cooling, 24.3 mL of 60% nitric acid was added dropwise. After stirring for 35 minutes, the solid was filtered off and washed with water and chloroform. The obtained solid was dried under reduced pressure to obtain 47.7 g (yield 77%) of an orange solid 3-hydroxy-4-nitro-2-naphthoic acid.
12.5 g of 3-hydroxy-4-nitro-2-naphthoic acid obtained by the above method and 1 mL of concentrated sulfuric acid were added to 200 mL of butanol, and the mixture was stirred at 117 ° C. for 48 hours. After concentrating the reaction solution, the precipitated solid was separated by filtration and washed with butanol. The obtained solid was dried under reduced pressure to obtain 7.52 g (yield 48%) of butyl 3-hydroxy-4-nitronaphthalene-2-carboxylate as a yellow solid.
17.1 g of butyl 3-hydroxy-4-nitronaphthalene-2-carboxylate obtained by the above method was dissolved in 175 mL of methanol, 6.28 g of 100% hydrazine monohydrate was added, and the mixture was stirred at 65 ° C. for 16 hours. did. After cooling the reaction solution, the precipitated solid was separated by filtration and washed with methanol. The obtained solid was dried under reduced pressure to obtain 14.6 g (yield 100%) of an orange solid 3-hydroxy-4-nitronaphthalene-2-carbohydrazide.

(Melting point: 185 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
7.1 (m, 1H), 7.4 (m, 2H), 7.8 (m, 1H), 8.4 (m, 1H), NH (3H), OH (1H) not detected)

-Compound i: 2.97 g of magnesium chloride was added to a 50 mL solution of diethyl 1,3-dihydroxynaphthalene-2-carbohydrazidomalonate in 50 mL of acetonitrile, and the mixture was ice-cooled. Next, 6.30 g of triethylamine was added dropwise and stirred for 30 minutes, then 4.82 g of phenylacetic acid chloride was added dropwise, the temperature was returned to room temperature, and the mixture was stirred for 4.5 hours. The reaction mixture was ice-cooled again, 200 mL of 2N hydrochloric acid was added, the mixture was extracted with ethyl acetate, and the organic layer was washed with saturated brine. It was dried over anhydrous magnesium sulfate, concentrated, and then dried under reduced pressure. The obtained pale yellow oily residue was ice-cooled, 15 mL of concentrated sulfuric acid was added dropwise, the temperature was returned to room temperature, and the mixture was stirred for 17 hours. The reaction mixture was ice-cooled, 35 mL of ice water was slowly added, and the precipitated solid was filtered off and washed with water. The obtained solid was dried under reduced pressure to obtain 6.09 g (yield 84%) of ethyl 1,3-dihydroxynaphthalene-2-carboxylate as a yellow solid.
To a solution of 800 mg of ethyl 1,3-dihydroxynaphthalene-2-carboxylate in 3 mL of methanol obtained by the above method, 0.21 g of 100% hydrazine monohydrate was added at room temperature, and the mixture was heated under reflux for 2.5 hours and returned to room temperature. Stirred for 12 hours. The precipitated solid was separated by filtration, the obtained solid was washed with methanol, and dried under reduced pressure to obtain 540 mg (yield 72%) of 1,3-dihydroxynaphthalene-2-carbohydrazide as an ocher solid.

(Melting point: 205 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
6.6 (s, 1H), 7.2 (m, 1H), 7.4 (m, 1H), 7.5 (d, 1H), 8.0 (d, 1H), NH (3H), OH (2H) not detected)

-Compound j: 2,4,6-trihydroxybenzohydrazide 2,4,6-trihydroxybenzoic acid monohydrate 10.0 g to a solution of 10.0 g of acetone in 100 mL of acetone was added with 2.96 g of sodium carbonate at room temperature and stirred for 10 minutes. Then, 7.04 g of dimethyl sulfate was added, the temperature was raised to 50 ° C., and the mixture was stirred for 5 hours. The reaction mixture was concentrated, water was added, the mixture was extracted with ethyl acetate, and the organic layer was washed with saturated brine. Further, the solid was dried over anhydrous magnesium sulfate, concentrated, suspended in a mixed solvent of ethyl acetate and hexane, separated by filtration, and dried under reduced pressure to be a pink solid, methyl 2,4,6-trihydroxybenzoate. 03 g (yield 62%) was obtained.
2.40 g of methyl 2,4,6-trihydroxybenzoate obtained by the above method was suspended in 10 mL of methanol, 0.98 g of 100% hydrazine monohydrate was added at room temperature, and the mixture was heated under reflux for 1.5 hours. The mixture was returned to room temperature and stirred for 12 hours. The precipitated solid was separated by filtration, the obtained solid was washed with methanol, and dried under reduced pressure to obtain 960 mg (yield 40%) of a beige solid 2,4,6-trihydroxybenzohydrazide.

(Melting point: 207 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
4.3 (br-s, 2H), 5.8 (s, 2H), 7.2 (s, 1H), 9.3 (br-s, 1H), 12.3 (br-s, 2H) )

Compound k: 2,6-dihydroxy-4-methylbenzohydrazide 2,6-dihydroxy-4-methylbenzoic acid 5.00 g of acetone in a 50 mL solution was added with 1.66 g of sodium carbonate at room temperature and stirred for 10 minutes. 3.94 g of dimethyl sulfate was added, the temperature was raised to 50 ° C., and the mixture was stirred for 5 hours. The reaction mixture was concentrated, water was added, the mixture was extracted with ethyl acetate, and the organic layer was washed with saturated brine. Further, it was dried over anhydrous magnesium sulfate, concentrated, and the precipitated solid was suspended in cold hexane, filtered off, dried under reduced pressure, and the white solid was 4.94 g of methyl 2,6-dihydroxy-4-methylbenzoate (yield 91). %) Was obtained.
4.50 g of methyl 2,6-dihydroxy-4-methylbenzoate obtained by the above method was suspended in 12 mL of methanol, 1.85 g of 100% hydrazine monohydrate was added at room temperature, and the mixture was heated under reflux for 12 hours. The temperature was returned to room temperature, the precipitated solid was filtered off, the obtained solid was washed with methanol, and dried under reduced pressure to give 3.09 g (yield 69%) of a pink solid 2,6-dihydroxy-4-methylbenzohydrazide. Obtained.

(Melting point: 180 ° C., ^{1 1} H-NMR (300 MHz, DMSO-d ₆ , δ ppm):
2.14 (s, 3H), 5.1 (br-s, 2H), 6.1 (s, 2H), 9.9 (br-s, 1H), 12.5 (br-s, 2H) )

<Examples 1 to 21, Comparative Examples 1 to 3>
A sample of the rubber composition was prepared according to the composition of the components in Table 1. The blending amount of each component is shown in parts by mass with respect to 100 parts by mass of the rubber component.

<Evaluation>
The following evaluation was performed on the obtained rubber composition sample.
(1) Low heat generation (tan δ index)
The rubber composition of each sample was vulcanized at 145 ° C. for 33 minutes to obtain vulcanized rubber. With respect to the obtained vulcanized rubber, a loss tangent (tan δ) was measured at a temperature of 50 ° C., a strain of 5%, and a frequency of 15 Hz using a viscoelasticity measuring device [manufactured by Leometrics].
The measured tan δ was shown as an index value when the reciprocal of tan δ in Comparative Example 2 was multiplied by 100 and 100 was set as 100. The larger the index value, the better the low heat generation. The evaluation results are shown in Table 1.

(2) Wear resistance (wear index)
The rubber composition of each sample was vulcanized at 145 ° C. for 33 minutes to obtain vulcanized rubber. Using a test piece cut out from each of the obtained vulcanized rubbers in a disk shape (diameter 16.2 mm x thickness 6 mm), a DIN wear test was performed according to JIS-K6264-2: 2005, and DIN wear was performed at room temperature. The amount of wear (mm ³ ) when the test was performed was measured.
Regarding the wear amount measured in each sample, the reciprocal of the wear amount of each sample is displayed as a wear index when the reciprocal of the wear amount of Comparative Example 2 is 100. The larger the index value, the smaller the amount of wear and the better the wear resistance. The evaluation results are shown in Table 1.

(3) Workability evaluation (Moony viscosity index)
The rubber composition of each sample was measured for Mooney viscosity in accordance with JIS K 630-1: 2001 (Mooney viscosity, Mooney scorch time).
The measured Mooney viscosity was multiplied by 100 after taking the reciprocal, and the index value when the inverse value × 100 of Comparative Example 2 was set to 100 was taken as the Mooney viscosity index. As for the Mooney viscosity index, the larger the value, the smaller the unvulcanized viscosity and the better the workability.

* 1: RSS # 1
* 2: "# 80" manufactured by Asahi Carbon Co., Ltd.
* 3: 3-Hydroxy-N'-(1,3-dimethylbutylidene) -2-naphthoic acid hydrazide synthesized by the following method does not correspond to the compound represented by the formula (I) (synthesis method).
A reactor equipped with a Dean-Stark apparatus reflux condenser and a stirrer was charged with 500 ml of methyl isobutyl ketone and 50.5 g (0.25 mol) of 3-hydroxy-2-naphthoic acid hydrazide, then heated and distilled. The mixture was heated under reflux for 5 hours while removing water. After cooling the reaction solution to 20 ° C., the precipitated crystals were separated by filtration and dried under reduced pressure to obtain slightly yellow crystals (67.6 g, yield 95%). As a result of NMR and IR analysis, these slightly yellow crystals were found to be 3-hydroxy-N'-(1,3-dimethylbutylidene) -2-naphthoic acid hydrazide.
(Melting point 146 ° C., 1H-NMR (DMSO) 0.90 (m, 6H), 1.93 (s, 3H), 2.00 (m, 1H), 2.17 (m, 2H), 7.38 (M, 2H), 7.46 (m, 1H), 7.75 (m, 1H), 7.95 (m, 1H), 8.58 (m, 1H), 11.15 (b, 1H) , 11.65 (b, 1H), IR (KBR) 3400-2400, 1650, 1550, 1510, 1470, 1360, 1230, 1170, 1140, 1120, 1050, 950, 900, 880, 770, 740, 670, 600, 550, 480 cm ^-1 )
* 4: "A / O MIX" manufactured by Sankyo Yuka Kogyo Co., Ltd.
* 5: N-Phenyl-N'-(1,3-dimethylbutyl) -p-phenylenediamine, "Nocrack 6C" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.
* 6: 2,2,4-trimethyl-1,2-dihydroquinoline polymer, "Nocrack 224" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.
* 7: N-cyclohexyl-2-benzothiazolesulfenamide, "Sun Cellar CM" manufactured by Sanshin Chemical Industry Co., Ltd.
* 8: 2,2'-methylenebis (4-methyl-6-tert-butylphenol), "Nocrack NS-6" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., molecular weight: 341
* 9: 4,4'-butylidenebis (3-methyl-6-tert-butylphenol), "Nocrack NS-30" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., molecular weight: 383
* 10: 2,6-di-tert-butyl-4-methylphenol, "Nocrack 200" manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd., molecular weight: 220
* 11: Acrylic acid 1'-hydroxy [2,2'-methylenebis (4-methyl-6-tert-butylbenzene)] -1-yl, Sumitomo Chemical Co., Ltd. "Sumilyzer GM", molecular weight: 395
* 12: Acrylic acid 1'-hydroxy [2,2'-ethylidenebis [4,6-bis (1,1-dimethylpropyl) benzene]] -1-yl, "Sumilyzer GS" manufactured by Sumitomo Chemical Co., Ltd., Molecular weight: 548

For each Example and Comparative Example, the total value of Mooney viscosity index, tan δ index, and wear index was calculated and used as a comprehensive evaluation. The higher the overall evaluation, the higher the level of workability, low heat generation and wear resistance.
From the results in Table 1, the rubber compositions of each example have a high overall evaluation with respect to the rubber compositions of each comparative example, and can achieve both workability, low heat generation, and abrasion resistance at a high level. I understand.

According to the present invention, it is possible to provide a rubber composition having low heat generation, excellent wear resistance and workability. Further, according to the present invention, it is possible to provide a tire having low heat generation and excellent productivity.

Claims (18)

A rubber composition comprising a rubber component containing a diene rubber, a filler, a compound represented by the following formula (I), and an antiaging agent containing a compound having a phenol group. ..

(In the formula, A is an aryl group and has at least two polar groups, the polar groups may be the same or different. R ¹ and R ² are independently hydrogen. It is at least one substituent selected from the group consisting of an atom, an acyl group, an amide group, an alkyl group, a cycloalkyl group and an aryl group, and the substituent is one or more of O, S and N atoms. May be included.) The rubber composition according to claim 1, wherein at least one of the polar groups of A in the compound represented by the formula (I) is a hydroxyl group, an amino group or a nitro group. The rubber composition according to claim 2, wherein at least one of the polar groups of A in the compound represented by the formula (I) is a hydroxyl group. The rubber composition according to claim 3, wherein at least two of the polar groups of A in the compound represented by the formula (I) are hydroxyl groups. The rubber composition according to any one of claims 1 to 4, wherein A in the compound represented by the formula (I) is a phenyl group or a naphthyl group. The rubber composition according to any one of claims 1 to 5, wherein both R ¹ and R ² in the compound represented by the formula (I) are hydrogen atoms. The rubber composition according to any one of claims 1 to 6, wherein the compound represented by the formula (I) has a molecular weight of 250 or less. The rubber composition according to any one of claims 1 to 7, wherein the compound represented by the formula (I) has a melting point of 80 ° C. or higher and lower than 250 ° C. Any one of claims 1 to 8, wherein the content of the compound represented by the formula (I) is 0.05 to 30 parts by mass with respect to 100 parts by mass of the rubber component. The rubber composition according to. The compounds represented by the formula (I) are 2,6-dihydroxybenzohydrazide, 2,3-dihydroxybenzohydrazide, 2,4-dihydroxybenzohydrazide, 2,5-dihydroxybenzohydrazide, 4-amino-2-. Hydroxybenzohydrazide, 3,5-dihydroxynaphthalene-2-carbhydrazide, 4-amino-3-hydroxynaphthalene-2-carbhydrazide, 3-hydroxy-4-nitronaphthalene-2-carbhydrazide, 1,3-dihydroxynaphthalene Claims 1 to 1, characterized in that it is at least one selected from the group consisting of -2-carbohydrazide, 2,4,6-trihydroxybenzohydrazide and 2,6-dihydroxy-4-methylbenzohydrazide. The rubber composition according to any one of 9. The rubber composition according to any one of claims 1 to 10, wherein the diene-based rubber is a natural rubber. The rubber composition according to any one of claims 1 to 11, wherein the filler contains carbon black. The rubber composition according to any one of claims 1 to 12, wherein the content of the filler is 10 to 160 parts by mass with respect to 100 parts by mass of the rubber component. The rubber composition according to any one of claims 1 to 13, wherein the compound having a phenol group has a molecular weight ratio of 250 or less to the number of phenol groups. The rubber composition according to any one of claims 1 to 14, wherein the total content of the anti-aging agent is 0.05 to 10 parts by mass with respect to 100 parts by mass of the rubber component. Stuff. The rubber composition according to any one of claims 1 to 15, wherein the proportion of the compound having a phenol group in the antioxidant is 20 to 100% by mass. Any of claims 1 to 16, wherein the anti-aging agent further contains an amine-based anti-aging agent, and the proportion of the amine-based anti-aging agent in the anti-aging agent is 80% by mass or less. The rubber composition according to item 1. A tire using the rubber composition according to any one of claims 1 to 17.