JP2016204417A - Rubber composition and vibration-proof rubber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition that can achieve vibration-proof performance as well as durability, such as tensile fatigue characteristics, and energy saving, and a vibration-proof rubber obtained by curing the same.SOLUTION: A rubber composition comprises a rubber component comprising diene rubber, carbon black, and a sulfide compound having an organic group comprising a benzazolyl structure, where the carbon black has a nitrogen adsorption specific surface area of more than 70 m/g to 120 m/g or less, and the sulfide compound is blended in an amount of 0.2-2.1 pts.mass relative to 100 pts.mass of the carbon black. There is also provided a vibration-proof rubber obtained by curing the rubber composition.SELECTED DRAWING: None

Description

  The present invention relates to a rubber composition and an anti-vibration rubber using the same.

  Conventionally, anti-vibration rubber has been used in the fields of automobiles, general industrial machines, and the like in order to prevent vibration and noise of an engine and a vehicle body. As performance required for such an anti-vibration rubber, in addition to the anti-vibration performance, there are durability such as stretch fatigue characteristics, energy saving, and the like.

In order to improve the vibration isolation performance, it is effective to sufficiently reduce the value of the dynamic magnification (dynamic spring constant (Kd) / static spring constant (Ks)) of the rubber composition used for the vibration isolation rubber. Therefore, the smaller the dynamic spring constant in a vibration state for transmitting vibrations of an automobile engine or the like, and the larger the static rigidity, i.e., the static spring constant indicating the support performance of the engine or the vehicle body, the better the vibration isolation performance.
In order to reduce the dynamic ratio of the rubber composition, a conventional rubber component having a low dynamic ratio and a high strength, or a natural rubber blended with a synthetic rubber such as butadiene rubber or styrene butadiene rubber mainly composed of natural rubber. And carbon black blends have been used.

  In order to improve durability and energy saving, a technique for improving the dispersion of fillers using modified polymers and various additives has been studied. For example, Patent Document 1 discloses blending terminal-modified butadiene and carbon black in addition to natural rubber. Also, a rubber composition using a bismaleimide compound and a diazole vulcanization accelerator as a diene rubber has been proposed (see, for example, Patent Document 2).

JP 2004-285511 A JP 2005-194501 A

However, with the method described in Patent Document 1, the dynamic magnification cannot be lowered, and sufficient performance cannot be obtained in terms of durability and energy saving, and it is difficult to meet the severe demands of customers in recent years. there were. In addition, although the method described in Patent Document 2 can cope with the dynamic magnification, durability, in particular, elongation fatigue characteristics have not been studied, and vibration isolation performance, durability, and energy saving performance It was difficult to achieve both.
As described above, in the rubber composition, the vibration proof performance, durability such as stretch fatigue characteristics, and energy saving are contradictory characteristics, and it has been difficult to improve these characteristics at the same time with the conventional compounding. .

  The present invention has been made in view of the above circumstances, and provides a rubber composition capable of achieving both vibration isolation performance and durability such as stretch fatigue characteristics and energy saving, and a vibration isolation rubber obtained by curing the rubber composition. For the purpose.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that the problem can be solved by the following invention. That is, the present invention provides a rubber composition having the following constitution and a vibration-proof rubber.

1. A rubber component containing a diene rubber, carbon black, and a sulfide compound having an organic group containing a benzazolyl structure, wherein the carbon black has a nitrogen adsorption specific surface area of more than 70 m ² / g and not more than 120 m ² / g, The rubber composition whose compounding quantity of this sulfide compound with respect to 100 mass parts of black is 0.2-2.1 mass parts.
2. Anti-vibration rubber obtained by curing the rubber composition according to the above 1.

  ADVANTAGE OF THE INVENTION According to this invention, the rubber composition which can make durability and energy-saving property, such as vibration-proof performance and a stretch fatigue characteristic, and the vibration-proof rubber formed by hardening it can be provided.

First, the rubber composition of the present invention will be described.
<Rubber composition>
The rubber composition of the present invention contains a rubber component containing a diene rubber, carbon black, and a sulfide compound having an organic group containing a benzazolyl structure, and the nitrogen adsorption specific surface area of the carbon black is more than 70 m ² / g more than 120 m ^2. / G or less, and the compounding amount of the sulfide compound with respect to 100 parts by mass of the carbon black is 0.2 to 2.1 parts by mass.
Hereinafter, the components contained in the rubber composition of the present invention will be described.

(Rubber component)
The rubber composition of the present invention employs a rubber component containing a diene rubber. There are no particular limitations on the type of diene rubber, and examples include natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, chloroprene rubber, and acrylonitrile-butadiene rubber. One of these is used alone. Alternatively, two or more kinds can be used in combination. In the present invention, in addition to basic physical properties such as tensile strength, from the viewpoint of obtaining durability such as vibration proof performance and elongation fatigue properties, natural rubber alone or natural rubber and other diene rubbers 2 It can be suitably used in combination of more than one species, and it is particularly preferable to use natural rubber alone.

  As long as it does not deviate from the object of the present invention, rubber other than diene can be used as the rubber component. Examples thereof include synthetic rubbers such as isobutylene-isoprene rubber, silicone rubber, acrylic rubber, ethylene propylene rubber, acrylate butadiene rubber, urethane rubber, chlorosulfonated rubber, chlorinated polyethylene, epichlorohydrin rubber, and fluororubber. Further, modified synthetic rubbers in which the molecular chain ends of these synthetic rubbers are modified can also be used. The synthetic rubber and the modified synthetic rubber can be used by appropriately selecting one or two or more from the above.

  In the present invention, the proportion of the diene rubber contained in the rubber component is preferably 70% by mass or more, more preferably 80% by mass or more, still more preferably 90% by mass or more, and particularly preferably 100% by mass. By setting the ratio of the diene rubber, in addition to basic physical properties such as tensile strength, durability such as vibration-proof performance and elongation fatigue properties can be obtained.

(Carbon black)
The rubber composition of the present invention includes carbon black, and the carbon black needs to have a nitrogen adsorption specific surface area (N ₂ SA) of more than 70 m ² / g and 120 m ² / g or less. When the nitrogen adsorption specific surface area of carbon black is within the above range, in addition to basic physical properties such as tensile strength, durability such as vibration proof performance and elongation fatigue properties can be obtained. Here, the nitrogen adsorption specific surface area (N ₂ SA) is a value measured according to the provisions of JIS K 6217-2: 2001.
In the present invention, vibration damping ability, from the viewpoint of durability of the stretch fatigue properties, it is preferable that the nitrogen adsorption specific surface area _(N 2 SA) is less than ^70m 2 / g Ultra ^{90m 2} / g, ^72~88m 2 / G is more preferable.

Examples of such carbon black include HAF (nitrogen adsorption specific surface area: 75 to 80 m ² / g), HS-HAF (nitrogen adsorption specific surface area: 78 to 83 m ² / g), and LS-HAF (nitrogen) which are standard varieties. Adsorption specific surface area: 80 to 85 m ² / g), HAF grade such as LI-HAF (nitrogen adsorption specific surface area: 73 to 75 m ² / g), HS-IISAF (nitrogen adsorption specific surface area: 96 to 101 m ² / g), ISAF grades such as LS-ISAF (nitrogen adsorption specific surface area: 104 to 108 m ² / g), ISAF (nitrogen adsorption specific surface area: 114 to 120 m ² / g), N339 (nitrogen adsorption specific surface area: 88 to 96 m ² / g) Etc. are preferable, and these can be used alone or in combination of two or more. Among them, HAF class is preferable from the viewpoint of obtaining durability such as vibration proof performance and elongation fatigue characteristics in addition to basic physical properties such as tensile strength.

Further, DBP oil absorption of the carbon black (dibutyl phthalate absorption) is preferably ^{70~140cm 3 / 100g, 80~130cm 3 /} 100g and more preferably. When the DBP oil absorption is within the above range, durability such as vibration proof performance and elongation fatigue characteristics can be obtained in addition to basic physical properties such as tensile strength. Here, DBP absorption amount, JIS K 6217-4: is measured according to 2001, the capacity of the dibutyl phthalate (DBP) absorbed per carbon black 100g ^(cm 3 / 100g).

  The content of carbon black is not particularly limited, but is preferably 5 to 100 parts by mass, more preferably 15 to 60 parts by mass with respect to 100 parts by mass of the rubber component. When the carbon black content is within the above range, in addition to basic physical properties such as tensile strength, durability such as anti-vibration performance and elongation fatigue properties can be obtained.

(Sulfide compound having an organic group containing a benzazolyl structure)
The rubber composition of the present invention needs to contain a sulfide compound having an organic group containing a benzazolyl structure. The sulfide compound functions as a coupling agent for carbon black, and in combination with carbon black at a predetermined ratio, in addition to basic physical properties such as tensile strength, durability such as vibration proof performance and elongation fatigue characteristics. And energy saving properties can be obtained.
The sulfide compound having an organic group containing a benzazolyl structure is particularly suitable as long as the organic group is bonded to both ends of the sulfide portion composed of a sulfur atom and the organic group contains a benzazolyl structure represented by the following general formula (2). Not limited.

In formula (2), X represents an O atom, an S atom, —NH—, or —NR ² —, and R ¹ and R ² are a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an alkyl group having 2 to 6 carbon atoms. An alkenyl group, a C3-C6 cycloalkyl group, and a C3-C6 cycloalkenyl group are shown.

  In the present invention, it is preferably a sulfide compound containing two or more organic groups represented by the above formula (2), and an organic group containing a benzazolyl structure represented by the above formula (2) at both ends of the sulfide part. It is more preferable that it is a sulfide compound having a bis body structure in which is bonded, and examples of such a sulfide compound include those represented by the following general formula (1).

(In formula (1), X represents an O atom, an S atom, —NH—, or —NR ² —, R ¹ and R ² are a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and ^{2 to} 6 carbon atoms. An alkenyl group, a cycloalkyl group having 3 to 6 carbon atoms, and a cycloalkenyl group having 3 to 6 carbon atoms, and a plurality of X and R ¹ may be the same or different. M represents an integer of 1 to 6, n represents an integer of 0 to 4, and a plurality of m and n may be the same or different.

The alkyl group having 1 to 6 carbon atoms may be linear or branched, and examples thereof include various propyl groups such as methyl group, ethyl group, propyl group and isopropyl group, n-butyl group, isobutyl group and t-butyl. Examples include various butyl groups such as a group, various pentyl groups, and various hexyl groups.
The alkenyl group having 2 to 6 carbon atoms may be linear or branched. For example, a vinyl group, 2-propenyl group, 2-butenyl group, 3-butenyl group, 4-pentenyl group, 2-methyl-2 -A propenyl group, 2-methyl-2-butenyl group, 3-methyl-2-butenyl group, pentenyl group, hexenyl group and the like can be mentioned.
Examples of the cycloalkyl group having 3 to 6 carbon atoms include a cyclopropyl group, a cyclopentyl group, and a cyclohexyl group.
Examples of the C3-C6 cycloalkenyl group include a cyclopropenyl group and a cyclopentenyl group.
In addition, these alkyl groups, alkenyl groups, cycloalkyl groups, and cycloalkenyl groups may have a substituent. Examples of the substituent include a halogen atom, an acyl group, a carboxyl group, an ester group, and a carbamoyl group. Etc., and at least one selected from these is preferable.

  l is preferably an integer of 2 to 4. M is preferably an integer of 1 to 4, more preferably an integer of 2 to 4, n is preferably an integer of 0 to 2, more preferably 0 or 1, and particularly preferably 0.

  Particularly preferred sulfide compounds include 2,2′-bis (benzimidazolyl-2) ethyl disulfide, 2,2′-bis (benzimidazolyl-2) ethyl tetrasulfide, and 2,2′-bis (benzoxazolyl- 2) Ethyl disulfide, 2,2'-bis (benzoxazolyl-2) ethyl tetrasulfide, 2,2'-bis (benzthiazolyl-2) ethyl disulfide, and 2,2'-bis (benzthiazolyl-2) ethyl Tetrasulfide etc. are mentioned.

The compounding quantity of the sulfide compound with respect to 100 mass parts of carbon black needs to be 0.2-2.1 mass parts. As the carbon black used in the present invention, one having a large nitrogen absorption specific surface area (one having a smaller average particle diameter) such as ISAF class or HAF class is used. In the present invention, by combining such carbon black and a specific sulfide compound in the above blending amount, in addition to basic physical properties such as tensile strength, durability such as vibration proof performance, elongation fatigue characteristics, and energy saving. Sex is obtained. From the viewpoint of further improving these effects, among the carbon blacks defined in the present invention, in the case of employing those having a small nitrogen adsorption specific surface area of more than 70 m ² / g and 90 m ² / g or less, 100 parts by mass of the carbon black It is preferable that the compounding quantity of the sulfide compound with respect to is 0.2-1.0 mass part, and it is more preferable that it is 0.2 mass part or more and less than 1.0 mass part.

(Other ingredients)
In the rubber composition of the present invention, various additives such as a crosslinking agent such as a rubber component, a filler carbon black, and a sulfide compound having an organic group containing a benzazolyl structure as a coupling agent for carbon black, for example, a crosslink Fillers, vulcanization accelerators, zinc white, fatty acids, carbon black and silica fillers (hereinafter referred to as other fillers), silane coupling agents, anti-aging agents, plasticizers, softeners, processing aids, etc. It can contain suitably in the range which is not contrary to the objective of this invention. Hereinafter, each of these components will be described.

There is no restriction | limiting in particular as a crosslinking agent, According to the objective, it can select suitably. For example, sulfur crosslinking agents, organic peroxide crosslinking agents, inorganic crosslinking agents, polyamine crosslinking agents, resin crosslinking agents, sulfur compound crosslinking agents, oxime-nitrosamine crosslinking agents, sulfur, etc. Sulfur is preferable as the crosslinking agent used in the rubber composition.
There is no restriction | limiting in particular as a compounding quantity of the crosslinking agent in a rubber composition, Although it can select suitably according to the objective, 0.3 mass part-10 mass parts are preferable with respect to 100 mass parts of rubber components. If the blending amount of the cross-linking agent is 0.3 parts by mass or more, the cross-linking can surely proceed. If it is 10 parts by mass or less, the cross-linking may proceed during kneading with some cross-linking agents. Further, the physical properties of the crosslinked product can be prevented from being impaired.

  Moreover, when employ | adopting sulfur as a crosslinking agent, 0.3 mass part-5 mass parts are preferable with respect to 100 mass parts of rubber components. When the amount of sulfur is 0.3 parts by mass or more, a sufficient vulcanization effect is obtained, and the target performance is easily achieved. In addition, when the sulfur content is 5 parts by weight or less, the rubber component in the rubber composition is not excessively cross-linked, and the resulting anti-vibration rubber is prevented from becoming brittle, and the fatigue performance of the rubber is reduced. Can be suppressed.

As the vulcanization accelerator, CBS (N-cyclohexyl-2-benzothiazylsulfenamide), TBBS (Nt-butyl-2-benzothiazylsulfenamide), TBSI (Nt-butyl-2) -Sulfenamide-based vulcanization accelerators such as benzothiazylsulfenimide); guanidine-based vulcanization accelerators such as DPG (diphenylguanidine); TMTD (tetramethyldisulfide), TETD (tetraethylthiuram disulfide), TBTD Examples include thiuram vulcanization accelerators such as (tetrabutyl thiuram disulfide) and tetrabenzyl thiuram disulfide; zinc dialkyldithiophosphate. These may be used alone or in combination of two or more.
The content of the vulcanization accelerator is preferably 0.1 to 3 parts by mass, more preferably 0.5 to 2.5 parts by mass with respect to 100 parts by mass of the rubber component.

From the viewpoint of accelerating vulcanization, a vulcanization acceleration aid such as zinc white or fatty acid can be contained in the rubber composition. The fatty acid may be saturated, unsaturated, linear or branched. Also, the number of carbon atoms is not particularly limited, and for example, one having 1 to 30 carbon atoms, preferably 15 to 30 carbon atoms can be used.
Specific examples of the fatty acid include cyclohexane acid (cyclohexanecarboxylic acid), naphthenic acid such as alkylcyclopentane having a side chain, hexanoic acid, octanoic acid, decanoic acid (including branched carboxylic acid such as neodecanoic acid), dodecanoic acid , Saturated fatty acids such as tetradecanoic acid, hexadecanoic acid, and octadecanoic acid (stearic acid), unsaturated fatty acids such as methacrylic acid, oleic acid, linoleic acid, and linolenic acid, and resin acids such as rosin, tall oil acid, and abietic acid It is done. These may be used alone or in combination of two or more. In the present invention, zinc white and stearic acid can be preferably used. The content of these vulcanization accelerators in the rubber composition is not particularly limited, but is preferably 1 to 10 parts by mass, more preferably 1 to 7 parts by mass with respect to 100 parts by mass of the rubber component. can do. When the content of the vulcanization accelerating auxiliary is 1 part by mass or more, kneading workability of the rubber composition is hardly impaired, and an increase in dynamic magnification can be suppressed. Less likely to cause sulfur delay.

  Other fillers include inorganic fillers such as silica, fine particle magnesium silicate, heavy calcium carbonate, magnesium carbonate, clay and talc, high styrene resin, coumarone indene resin, phenol resin, lignin, modified melamine resin and Organic fillers such as petroleum resins can be used. These can be used individually by 1 type or in combination of 2 or more types.

From the viewpoint of improving the dispersibility of the filler in the rubber composition and improving the reinforcing property of the vibration-proof rubber, the rubber composition of the present invention can contain a silane coupling agent.
As silane coupling agents, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy Propyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-chloropropylmethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β (Aminoethyl) -γ-aminopropyltrimethoxysilane, bis-triethoxysilylpropyl tetrasulfide, bis-triethoxysilylpropyl disulfide and the like can be mentioned.
These silane coupling agents can be used alone or in combination of two or more. Moreover, the content is not particularly limited, but is preferably 1 to 10% by mass, more preferably 5 to 10% by mass with respect to the content of the filler containing carbon black. . When the content of the silane coupling agent is 1% by mass or more with respect to the content of the filler, the dispersibility of the filler and the reinforcing effect of the vibration-proof rubber are easily expressed sufficiently, and the content is 10% by mass or less. Therefore, an excessive amount of the silane coupling agent is suppressed, which is preferable in terms of economy.

  As the anti-aging agent, known ones can be used, and are not particularly limited, and examples thereof include phenol-based anti-aging agents, imidazole-based anti-aging agents, and amine-based anti-aging agents. These anti-aging agents can be used alone or in combination of two or more. The content of the antioxidant is preferably 1 to 10 parts by mass, more preferably 1 to 7 parts by mass with respect to 100 parts by mass of the rubber component.

  Examples of the plasticizer include waxes such as known paraffin wax and microcrystalline wax, amide compounds such as stearic acid amide, oleic acid amide, and erucic acid amide, and the like, and one kind is used alone or two or more kinds are used in combination. Use it. In particular, in the present invention, paraffin wax and microcrystalline wax can be preferably used. By including these, molding workability can be improved. Although content in particular is not restrict | limited, Preferably it can be set as 0.5-10 mass parts with respect to 100 mass parts of rubber components.

As the softener, known ones can be used, and are not particularly limited. Specifically, process oils such as aromatic oils, naphthenic oils, paraffin oils, vegetable oils such as palm oil, alkylbenzene oils, etc. Synthetic oil, castor oil, and the like can be used. In the present invention, naphthenic oil can be suitably used. These can be used individually by 1 type or in combination of 2 or more types. The content of these softening agents is not particularly limited, but can be preferably 1 to 80 parts by mass with respect to 100 parts by mass of the rubber component. When the content is within the above range, the kneading workability of the rubber composition is unlikely to be impaired.
When oil-extended rubber (that is, rubber containing a softening agent) is used as the rubber component, the total of the softening agent contained in the oil-extended rubber and the softening agent added separately during mixing What is necessary is just to adjust so that quantity may become the said range.

  In addition to the above components, the rubber composition of the present invention may be used as necessary in the case of antioxidants, lubricants, tackifiers, petroleum resins, UV absorbers, dispersants, compatibilizers. In addition, an appropriate amount of additives such as a homogenizing agent and a vulcanization retarder can be blended.

  When obtaining the rubber composition of the present invention, there is no particular limitation on the blending method of the above components, and all the components may be blended and kneaded at one time, or blended in two or three stages. And kneading may be performed. In kneading the components, a known kneader such as a roll, an internal mixer, a Banbury rotor or the like can be used. Furthermore, when the kneaded material is formed into a sheet shape or a belt shape, a known molding machine such as an extrusion molding machine or a press machine may be used.

<Anti-vibration rubber>
The anti-vibration rubber of the present invention is obtained by curing the rubber composition of the present invention.
The rubber composition can be cured by, for example, blending the aforementioned vulcanizing agent in the rubber composition and heating.
The curing conditions (vulcanization conditions) for curing the rubber composition are not particularly limited, but are usually 140 to 180 ° C., preferably 150 to 170 ° C., and 5 to 120 minutes. Can do.

  The anti-vibration rubber obtained by curing the rubber composition of the present invention is capable of satisfying both the anti-vibration performance, the durability such as the elongation fatigue characteristic, and the energy saving property in addition to the basic physical properties such as the tensile strength. is there. Therefore, it is suitably used as an anti-vibration rubber used in a harsh environment where these performances are required, particularly as an anti-vibration rubber used for automobile engine mounts, strut mounts, body mounts, suspension bushings, etc. However, it is not limited to these.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not restrict | limited to the following Example. Using the rubber composition obtained in each example, durability and energy saving were evaluated according to the following methods.

(Measurement of tan δ)
A sheet having a length of 40 mm, a width of 5 mm, and a thickness of 2 mm was prepared from the vibration-proof rubber obtained in each example, and the distance between chucks was 30 mm and the dynamic strain was 2% using a viscoelastic spectrometer (manufactured by Toyo Seiki Seisakusho Co., Ltd.). Then, dynamic viscoelasticity measurement was performed under measurement conditions of a frequency of 10 Hz, and loss tangent (tan δ) at 20 ° C. was measured. The loss tangent of each example was displayed as an index in the following tables, with the loss tangent of Comparative Examples 1, 3, 5, and 6 as 100, and used as an evaluation standard for energy saving.

(Measurement of number of stretch fatigue fractures)
In accordance with JIS K6270, with a dumbbell-shaped specimen, a test strain of 0 to 200%, a test fatigue frequency of 3.5 Hz gives a stretch fatigue (uniaxial stretch fatigue), and the number of times until the sample breaks (the number of stretch fatigue breaks) is measured. did. The number of times measured was shown as an index in the following tables, with the number of times of Comparative Example 1 being 100, and used as an evaluation standard for durability (elongation fatigue properties).

(Examples 1-4, Comparative Examples 1 and 2)
The components of the types and amounts shown in Table 1 below were kneaded in a Banbury mixer to obtain a rubber composition. Next, the obtained rubber composition was subjected to T90 × 2 (min) vulcanization treatment at 155 ° C. to produce a vibration-proof rubber. Here, T90 is a vulcanization curve with the vulcanization time as the horizontal axis and the torque as the vertical axis. The point at which the stress takes the maximum value is 100% vulcanization, and the point at the minimum value is 0% vulcanization. Is the vulcanization time (minutes) corresponding to 90% vulcanization.

The details of each component shown in Table 1 are as follows. Moreover, the compounding quantity of a sulfide compound is a compounding quantity (mass part) with respect to 100 mass parts of carbon black.
Rubber component: Natural rubber, "RSS # 1"
Carbon black: Tokai Carbon Co., Ltd. "SEAST 3", the nitrogen adsorption specific surface ^area: 79m 2 / g, DBP adsorption ^amount: 101cm 3 / 100g
Sulfide compound: 2,2′-bis (benzimidazolyl-2) ethyl disulfide, sulfide compound blended by Shikoku Kasei Kogyo Co., Ltd .: blending amount (part by mass) with respect to 100 parts by mass of carbon black.
Stearic acid: “Stearic acid 50S” manufactured by Shin Nippon Chemical Co., Ltd.
Zinc oxide: “No. 3 zinc white” manufactured by Hakusuitec Co., Ltd.
Anti-aging agent: N-phenyl-N ′-(1,3-dimethylbutyl) -p-phenylenediamine, “NOCRACK 6C” manufactured by Ouchi Shinsei Chemical Co., Ltd.
Sulfur: "Powdered sulfur" manufactured by Tsurumi Chemical Co., Ltd.
Vulcanization accelerator: Sulfenamide vulcanization accelerator, N-cyclohexyl-2-benzothiazolylsulfenamide, "Noxeller CZ" manufactured by Ouchi Shinsei Chemical Co., Ltd.

  From the results in Table 1, it was confirmed that the anti-vibration rubber using the rubber composition of the present invention was excellent in durability such as stretch fatigue properties and energy saving, and could achieve both of these performances. On the other hand, it was confirmed that the rubber using the rubber composition of the comparative example which does not contain a sulfide compound, or whose content is too low or too high, has not obtained excellent performance in terms of durability and energy saving. It was.

Claims (4)

A rubber component containing a diene rubber, carbon black, and a sulfide compound having an organic group containing a benzazolyl structure, wherein the carbon black has a nitrogen adsorption specific surface area of more than 70 m ² / g and not more than 120 m ² / g, The rubber composition whose compounding quantity of this sulfide compound with respect to 100 mass parts of black is 0.2-2.1 mass parts. The nitrogen adsorption specific surface area of carbon black is more than 70 m ² / g and 90 m ² / g or less, and the compounding amount of the sulfide compound with respect to 100 parts by mass of the carbon black is 0.2 to 1.0 part by mass. Rubber composition. The rubber composition according to claim 1 or 2, wherein the sulfide compound having an organic group containing a benzazolyl structure is a compound represented by the following general formula (1).
(In the formula (1), X represents an O atom, an S atom, —NH—, or —NR ² —, wherein R ¹ and R ² are an alkyl group having 1 to 6 carbon atoms and an alkenyl group having 2 to 6 carbon atoms. , A cycloalkyl group having 3 to 6 carbon atoms and a cycloalkenyl group having 3 to 6 carbon atoms, and a plurality of X and R ¹ may be the same or different, l is an integer of 1 to 4, and m is An integer of 1 to 4 is shown, n is an integer of 1 to 6, and a plurality of m and n may be the same or different.   Anti-vibration rubber obtained by curing the rubber composition according to any one of claims 1 to 3.