JP2018204033A - Method for producing rubber composition - Google Patents

Abstract

To produce a vulcanized rubber composition having a low loss factor. A compound (C) having a group or structure (A) capable of reacting with an olefinic double bond and a group or structure (B) capable of reacting or interacting with carbon black, and an olefinic double bond. A rubber composition comprising a step 1 of kneading a rubber component having carbon black and a kneaded product, and a step 2 of obtaining a rubber composition by kneading the kneaded product obtained in step 1 and zinc oxide. Manufacturing method. [Selection figure] None

Description

  The present invention relates to a method for producing a rubber composition.

  In recent years, there has been a demand for improvement in fuel consumption (that is, reduction in fuel consumption) of automobiles due to a demand for environmental protection. In the field of automobile tires, it is known that the fuel efficiency of automobiles is improved by reducing the loss factor (tan δ) of the vulcanized rubber composition used for tire manufacture.

  For example, in Patent Document 1, in order to reduce the loss factor of the vulcanized rubber composition, the formula (D):

[Definition of groups in formula (D) is as described in Patent Document 1. In addition, Formula (D) is described in Patent Document 1 as Formula (I). ]
And the use of at least one of the salt, the solvate thereof, and the solvate of the salt thereof.

  Further, in Patent Document 2, in order to reduce the loss factor of the vulcanized rubber composition, the formula (E):

[Definition of the group in the formula (E) is as described in Patent Document 2. The formula (E) is described as the formula (I) in Patent Document 2. ]
It is described that the compound represented by these is used.

JP 2013-209605 A JP 2013-159678 A

  In the rubber field, reduction of the loss factor (tan δ) of the vulcanized rubber composition is constantly demanded. The present invention has been made paying attention to such circumstances, and an object thereof is to produce a vulcanized rubber composition having a low loss factor.

The present invention that can achieve the above object is as follows.
[1] A compound (C) having a group or structure (A) capable of reacting with an olefinic double bond and a group or structure (B) capable of reacting or interacting with carbon black, and an olefinic double bond Step 1 for kneading a rubber component and carbon black to obtain a kneaded product, and Step 2 for kneading the kneaded product obtained in Step 1 and zinc oxide to obtain a rubber composition
The manufacturing method of the rubber composition containing this.
[2] Compound (C) is represented by the formula (I):

[In the formula (I),
R ¹ is a C _2-12 alkanediyl group that may have one or more substituents, a C _3-10 cycloalkanediyl group that may have one or more substituents, and one or more substituents. It represents a divalent C _6-12 aromatic hydrocarbon group which may have a hydrogen atom, or a combination thereof.
R ² and R ³ each independently have a hydrogen atom, a halogen atom, a hydroxy group, one or more C _1-6 alkoxy group which may have one or more substituents, and one or more substituents. Represents a good C _1-6 alkyl group, or a C _6-14 aryl group optionally having one or more substituents, or R ² and R ³ are bonded, and the carbon atom to which they are bonded; Together, they form a C _3-10 cycloalkenediyl group that may have one or more substituents.
R ⁴ is a hydroxy group, a C _1-6 alkoxy group optionally having one or more substituents, a C _6-14 aryloxy group optionally having one or more substituents, or —NR ^5. R ⁶ (wherein R ⁵ and R ⁶ each independently represents a hydrogen atom or a C _1-6 alkyl group which may have one or more substituents).
X represents -NH- or -O-. ]
And its salts, solvates and solvates thereof, and formula (II):

[In the formula (II),
R ⁷ and R ⁸ each independently represent a hydrogen atom or a C _1-6 alkyl group which may have one or more substituents, or R ⁷ and R ⁸ are bonded to each other to form one or more substituents. A C _2-12 alkanediyl group which may have a group is formed.
m represents an integer of 2 to 9.
n represents 1 or 2.
M ^{n +} represents H ⁺ or an n-valent metal ion. ]
The method according to [1] above, which is at least one selected from the group consisting of compounds represented by:
[3] The method according to [1] or [2] above, wherein the kneaded product obtained in step 1, the zinc oxide, and the sulfur component are kneaded in step 2 to obtain a rubber composition.
[4] The production method according to [1] or [2], further including Step 3 of kneading the rubber composition obtained in Step 2 and the sulfur component to obtain a rubber composition.
[5] A method for producing a vulcanized rubber composition, comprising vulcanizing the rubber composition obtained by the method according to [3] or [4].
[6] A rubber composition obtained by the method according to any one of [1] to [4].
[7] A vulcanized rubber composition obtained by the method according to [5].

  According to the present invention, a vulcanized rubber composition having a low loss factor can be produced.

<Compound (C)>
The present invention is characterized by using a compound (C) having a group or structure (A) capable of reacting with an olefinic double bond and a group or structure (B) capable of reacting or interacting with carbon black. I will. Only 1 type may be used for a compound (C) and it may use 2 or more types together.

Examples of the group or structure (A) include a group or structure capable of undergoing radical reaction or 1,3-dipolar addition reaction with an olefinic double bond. More specifically, examples of the group or structure (A) include an olefinic double bond, an amide group, a maleimide ring, a 1H-imidazole ring, a benzoxazole ring, a benzothiazole ring, * -SSO ₃ H or a salt thereof. , * —S—S— *, * —C≡N ⁺ —O ⁻ , * —C≡N ⁺ —N ⁻ — *, a structure represented by formula (i), a structure represented by formula (ii) Or a structure represented by formula (iii):

[In the above formula, * represents a bonding position. ]
Is mentioned. All of the amide group, maleimide ring, 1H-imidazole ring, benzoxazole ring, and benzothiazole ring described above may be a monovalent group or a divalent group. Examples of the amide group include * -CO-NH _2- *, * -NHCO- *, * -CONH ₂ (wherein * represents a bonding position). Examples of the maleimide ring include a 1-maleimidyl group. Examples of the 1H-imidazole ring include a 1-imidazolyl group. Examples of the benzoxazole ring include a benzoxazolyl group. Examples of the benzothiazole ring include a benzothiazolyl group.

  Examples of the group or structure (B) include an unsubstituted or monosubstituted amino group (preferably an unsubstituted amino group), a benzene ring, a furan ring, an oxazole ring, or a 1H-benzimidazole ring. All of the benzene ring, furan ring, oxazole ring and 1H-benzimidazole ring described above may be a monovalent group or a divalent group. Examples of the benzene ring include a phenyl group and a 1,4-phenylene group. Examples of the furan ring include a 2-furyl group and a 3-furyl group. Examples of the oxazole ring include a 2-oxazolyl group. Examples of the 1H-benzimidazole ring include a 2-benzimidazolyl group. These can react with the carboxy group of carbon black or can interact with the aromatic ring of carbon black by π-π.

  Specific examples of the compound (C) include the following compounds. However, the present invention is not limited to these compounds. [In the following formula, A represents O, S or NH, x represents an integer of 1 to 4, and y and z each independently represents an integer of 1 to 6.] Represent].

  Compound (C) is preferably of formula (I):

[In the formula (I),
R ¹ is a C _2-12 alkanediyl group that may have one or more substituents, a C _3-10 cycloalkanediyl group that may have one or more substituents, and one or more substituents. It represents a divalent C _6-12 aromatic hydrocarbon group which may have a hydrogen atom, or a combination thereof.
R ² and R ³ each independently have a hydrogen atom, a halogen atom, a hydroxy group, one or more C _1-6 alkoxy group which may have one or more substituents, and one or more substituents. Represents a good C _1-6 alkyl group, or a C _6-14 aryl group optionally having one or more substituents, or R ² and R ³ are bonded, and the carbon atom to which they are bonded; Together, they form a C _3-10 cycloalkenediyl group that may have one or more substituents.
R ⁴ is a hydroxy group (—OH), a C _1-6 alkoxy group optionally having one or more substituents, a C _6-14 aryloxy group optionally having one or more substituents, Or —NR ⁵ R ⁶ (wherein R ⁵ and R ⁶ each independently represents a hydrogen atom or a C _1-6 alkyl group optionally having one or more substituents). .
X represents -NH- or -O-. ]
And its salts, solvates and solvates thereof, and formula (II):

[In the formula (II),
R ⁷ and R ⁸ each independently represent a hydrogen atom or a C _1-6 alkyl group which may have one or more substituents, or R ⁷ and R ⁸ are bonded to each other to form one or more substituents. A C _2-12 alkanediyl group which may have a group is formed.
m represents an integer of 2 to 9.
n represents 1 or 2.
M ^{n +} represents H ⁺ or an n-valent metal ion. ]

Or a salt thereof, a solvate thereof, and a solvate of the salt thereof.

  Hereinafter, the “compound represented by the formula (I)” may be abbreviated as “compound (I)”. Similarly, compounds represented by other formulas may be abbreviated. In addition, “a compound represented by the formula (I), a salt thereof, a solvate thereof, and a solvate of the salt” may be abbreviated as “compound (I) and the like”. As for compound (I) etc. and compound (II) etc., all may use only 1 type and may use 2 or more types together.

Below, the definition of group is demonstrated first.
In the present specification, “C _xy ” means that the number of carbon atoms is x or more and y or less (x, y: integer).
In the present specification, examples of the “halogen atom” include fluorine, chlorine, bromine and iodine.

In the present specification, the alkyl group includes both a linear alkyl group and a branched alkyl group. In the present specification, examples of the “C _1-6 alkyl group” include a methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, isopropyl group, sec-butyl group, t-butyl group, 2 -Methylbutyl group, 2-ethylbutyl group, 3-methylbutyl group, 3-ethylbutyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group are mentioned.

Examples of the substituent that the C _1-6 alkyl group may have include, for example, a halogen atom, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group, a C _1-7 acyl group, and a C _1-7. Examples include an acyl-oxy group and a C _6-14 aryl group which may have one or more substituents.

In the present specification, examples of the “C _6-14 aryl group” include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 2-anthryl group, and a 9-anthryl group.

Examples of the substituent that the C _6-14 aryl group may have include, for example, a halogen atom, a C _1-6 alkyl group, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group, and a C _1-7. Examples include an acyl group, a C _1-7 acyl-oxy group, a C _6-14 aryl group, and a sulfo group.

In the present specification, the alkoxy group includes both a linear alkoxy group and a branched alkoxy group. In the present specification, examples of the “C _1-6 alkoxy group” include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, and a pentyloxy group. And hexyloxy group.

Examples of the substituent that the C _1-6 alkoxy group may have include, for example, a halogen atom, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group, a C _1-7 acyl group, and a C _1-7. Examples include an acyl-oxy group and a C _6-14 aryl group which may have one or more substituents.

In the present specification, examples of the “C _6-14 aryl group” contained in the C _6-14 aryloxy group include those described above.

In the present specification, examples of the “C _1-7 acyl group” include a formyl group, a C _1-6 alkyl-carbonyl group (eg, acetyl group, pivaloyl group), and a benzoyl group.

In the present specification, examples of the “C _1-6 alkoxy group” contained in the C _1-6 alkoxy-carbonyl group and the “C _1-7 acyl group” contained in the C _1-7 acyl-oxy group include, for example, Can be mentioned.

In the present specification, the alkanediyl group includes both a linear alkanediyl group and a branched alkanediyl group. In the present specification, examples of the “C _2-12 alkanediyl group” include an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, a propylene group, a 1-methyltrimethylene group, and 2-methyl. Trimethylene, 1-ethyltrimethylene, 2-ethyltrimethylene, 1-propyltrimethylene, 2-propyltrimethylene, 1-methyltetramethylene, 2-methyltetramethylene, 1-ethyltetra Methylene group, 2-ethyltetramethylene group, 1-propyltetramethylene group, 2-propyltetramethylene group, 1-methylpentamethylene group, 2-methylpentamethylene group, 3-methylpentamethylene group, 1-ethylpentamethylene group Group, 2-ethylpentamethylene group, 3-ethylpentamethylene group, 1-propylene Rupentamethylene group, 2-propylpentamethylene group, 3-propylpentamethylene group, 1-methylhexamethylene group, 2-methylhexamethylene group, 3-methylhexamethylene group, 1-ethylhexamethylene group, 2-ethyl Examples include a hexamethylene group, a 3-ethylhexamethylene group, a 1-propylhexamethylene group, a 2-propylhexamethylene group, and a 3-propylhexamethylene group.

As the substituent that the C _2-12 alkanediyl group may have, for example, a halogen atom, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group, a C _1-7 acyl group, a C _{1-1 7} acyl-oxy group, a C _6-14 aryl group _optionally having one or more substituents.

In the present specification, examples of the “C _3-10 cycloalkanediyl group” include cyclopropane-1,2-diyl group, cyclobutane-1,3-diyl group, cyclopentane-1,3-diyl group, cyclohexane Examples include -1,4-diyl group, cycloheptane-1,4-diyl group, cyclooctane-1,5-diyl group, cyclononane-1,5-diyl group, and cyclodecane-1,6-diyl group.

Examples of the substituent that the C _3-10 cycloalkanediyl group may have include a halogen atom, a C _1-6 alkyl group, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group, and C _{1. Examples} include a _-7 acyl group, a C _1-7 acyl-oxy group, and a C _6-14 aryl group which may have one or more substituents.

In the present specification, examples of the “C _3-10 cycloalkenediyl group” include cyclopropene-1,2-diyl group, cyclobutene-1,2-diyl group, cyclopentene-1,2-diyl group, cyclohexene- Examples include 1,2-diyl group, cycloheptene-1,2-diyl group, cyclooctene-1,2-diyl group, cyclononene-1,2-diyl group, and cyclodecene-1,2-diyl group.

Examples of the substituent that the C _3-10 cycloalkenediyl group may have include a halogen atom, a C _1-6 alkyl group, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group, and C _{1. Examples} include a _-7 acyl group, a C _1-7 acyl-oxy group, and a C _6-14 aryl group which may have one or more substituents.

In the present specification, examples of the “divalent C _6-12 aromatic hydrocarbon group” include a phenylene group (eg, 1,4-phenylene group), a naphthylene group (eg, 1,4-naphthylene group, 1 , 5-naphthylene group, 2,6-naphthylene group, 2,7-naphthylene group) and biphenyldiyl group (eg, 1,1′-biphenyl-4,4′-diyl group).

Examples of the substituent that the divalent C _6-12 aromatic hydrocarbon group may have include, for example, a halogen atom, a C _1-6 alkyl group, a C _1-6 alkoxy group, a C _1-6 alkoxy-carbonyl group. Group, a C _1-7 acyl group, a C _1-7 acyl-oxy group, a C _6-14 aryl group, and a sulfo group. The sulfo group is a group represented by —SO ₃ H.

Next, preferred groups in formula (I) will be described.
R ¹ is preferably a C _2-12 alkanediyl group or a divalent C _6-12 aromatic hydrocarbon group, more preferably a C _2-12 alkanediyl group or a phenylene group, still more preferably a phenylene group. And particularly preferably a 1,4-phenylene group.

R ² and R ³ are each independently preferably a hydrogen atom or a C _1-6 alkyl group, more preferably a hydrogen atom.

R ⁴ is preferably a hydroxy group, a C _1-6 alkoxy group optionally having one or more substituents, or a C _6-14 aryloxy group optionally having one or more substituents. More preferably a hydroxy group or a C _1-6 alkoxy group, still more preferably a hydroxy group.
X is preferably —NH—.

  Compound (I) is preferably of formula (Ia):

[In the formula (Ia), R ^{1 to} R ⁴ and X are as defined above. ]
It is a compound represented by these.

Examples of the salt of compound (I) include (a) an amine salt formed by —NH ₂ of compound (I) and another acid, and (b) when —NH— is —NH— of compound (I). Examples include amine salts formed by-and other acids, and (c) carboxylates formed by -COOH and other bases of compound (I) when R ⁴ is a hydroxy group (-OH). . The other acid that forms the amine salt of (a) and (b) may be either an organic acid or an inorganic acid, and the base that forms the carboxylate salt of (c) is an organic base or an inorganic base. Either is acceptable. The salt of compound (I) is preferably a carboxylate, more preferably at least one selected from the group consisting of an alkali metal carboxylate and an alkaline earth metal carboxylate, and more preferably an alkali carboxylate A metal salt, particularly preferably a sodium carboxylate.

  The solvent that forms the solvate of Compound (I) and the solvate of the salt of Compound (I) may be water or an organic solvent (for example, methanol). The solvent forming the solvate is preferably water or methanol, more preferably water.

  In one embodiment of the present invention, compound (I) and the like are preferably a solvate of a salt of compound (I), more preferably a solvate of a carboxylate salt of compound (I), and still more preferably A solvate of a carboxylic acid alkali metal salt, particularly preferably a solvate of a carboxylic acid sodium salt. In this embodiment, it is desirable that compound (I) is compound (Ia).

  Specific examples of compound (I) or a salt thereof are shown below.

  Compound (I) and the like can be produced by the method described in Patent Document 1 or a method according to the method.

Next, preferred groups in formula (II) will be described.
R ⁷ and R ⁸ are each independently preferably a hydrogen atom or a C _1-6 alkyl group optionally having one or more substituents, more preferably a hydrogen atom.

m is preferably 2 to 7, and more preferably 2 to 5.
n is preferably 1.

Examples of n-valent metal ions include alkali metal ions (eg, lithium ions, sodium ions, potassium ions), alkaline earth metal ions (eg, cesium ions, magnesium ions, calcium ions, strontium ions, barium ions), Manganese ion, iron ion, copper ion, zinc ion, etc. are mentioned. M ^{n +} is preferably H ⁺ or an alkali metal ion, more preferably H ⁺ or a sodium ion, and still more preferably H ⁺ .

  Examples of the compound (II) include S- (aminoalkyl) thiosulfuric acid, S- (aminoalkyl) thiosulfate, S- (N, N-dialkylaminoalkyl) thiosulfuric acid, S- (N, N-dialkyl). Aminoalkyl) thiosulfate, S- (N-monoalkylaminoalkyl) thiosulfuric acid, S- (N-monoalkylaminoalkyl) thiosulfate and the like.

  Examples of S- (aminoalkyl) thiosulfuric acid include S- (2-aminoethyl) thiosulfuric acid, S- (3-aminopropyl) thiosulfuric acid, S- (4-aminobutyl) thiosulfuric acid, and S- (5 -Aminopentyl) thiosulfuric acid, S- (6-aminohexyl) thiosulfuric acid, S- (7-aminoheptyl) thiosulfuric acid, S- (8-aminooctyl) thiosulfuric acid, S- (9-aminononyl) thiosulfuric acid and the like Is mentioned.

  Examples of S- (aminoalkyl) thiosulfate include sodium S- (2-aminoethyl) thiosulfate, sodium S- (3-aminopropyl) thiosulfate, sodium S- (4-aminobutyl) thiosulfate, S- (5-aminopentyl) sodium thiosulfate, S- (6-aminohexyl) sodium thiosulfate, S- (7-aminoheptyl) sodium thiosulfate, S- (8-aminooctyl) sodium thiosulfate, S- (9-aminononyl) sodium thiosulfate and the like.

  Examples of S- (N, N-dialkylaminoalkyl) thiosulfuric acid include S- (2-N, N-dimethylaminoethyl) thiosulfuric acid, S- (3-N, N-dimethylaminopropyl) thiosulfuric acid, S- (4-N, N-dimethylaminobutyl) thiosulfuric acid, S- (5-N, N-dimethylaminopentyl) thiosulfuric acid, S- (6-N, N-dimethylaminohexyl) thiosulfuric acid, S- (7-N, N-dimethylaminoheptyl) thiosulfuric acid, S- (8-N, N-dimethylaminooctyl) thiosulfuric acid, S- (9-N, N-dimethylaminononyl) thiosulfuric acid and the like can be mentioned.

  Examples of S- (N, N-dialkylaminoalkyl) thiosulfate include sodium S- (2-N, N-dimethylaminoethyl) thiosulfate and S- (3-N, N-dimethylaminopropyl) thio. Sodium sulfate, S- (4-N, N-dimethylaminobutyl) sodium thiosulfate, S- (5-N, N-dimethylaminopentyl) sodium thiosulfate, S- (6-N, N-dimethylaminohexyl) Sodium thiosulfate, S- (7-N, N-dimethylaminoheptyl) sodium thiosulfate, S- (8-N, N-dimethylaminooctyl) sodium thiosulfate, S- (9-N, N-dimethylaminononyl) ) Sodium thiosulfate and the like.

  Examples of S- (N-monoalkylaminoalkyl) thiosulfuric acid include S- (2-N-methylaminoethyl) thiosulfuric acid, S- (3-N-methylaminopropyl) thiosulfuric acid, and S- (4- N-methylaminobutyl) thiosulfuric acid, S- (5-N-methylaminopentyl) thiosulfuric acid, S- (6-N-methylaminohexyl) thiosulfuric acid, S- (7-N-methylaminoheptyl) thiosulfuric acid S- (8-N-methylaminooctyl) thiosulfuric acid, S- (9-N-methylaminononyl) thiosulfuric acid and the like.

  Examples of S- (N-monoalkylaminoalkyl) thiosulfate include sodium S- (2-N-methylaminoethyl) thiosulfate, sodium S- (3-N-methylaminopropyl) thiosulfate, S- (4-N-methylaminobutyl) sodium thiosulfate, S- (5-N-methylaminopentyl) sodium thiosulfate, S- (6-N-methylaminohexyl) sodium thiosulfate, S- (7-N- Methylaminoheptyl) sodium thiosulfate, S- (8-N-methylaminooctyl) sodium thiosulfate, S- (9-N-methylaminononyl) sodium thiosulfate and the like.

  Compound (II) is preferably at least one selected from the group consisting of S- (aminoalkyl) thiosulfuric acid and S- (aminoalkyl) thiosulfuric acid salt, more preferably S- (aminoalkyl) thiosulfuric acid. More preferably S- (3-aminopropyl) thiosulfuric acid.

  Compound (II) can be produced by the method described in Patent Document 2 or a method according to the method.

  The amount of compound (C) used is preferably 0.1 to 10 parts by weight, more preferably 0.25 to 8 parts by weight, and more preferably 100 parts by weight of the rubber component having an olefinic double bond. Preferably it is 0.5-4 weight part.

<Rubber component having an olefinic double bond>
One feature of the present invention is to use a rubber component having an olefinic double bond. Only 1 type may be used for the rubber component which has an olefinic double bond, and 2 or more types may be used together.

  Rubber components having an olefinic double bond include natural rubber (NR) and modified natural rubber (eg, epoxidized natural rubber, deproteinized natural rubber); isoprene rubber (IR), styrene / butadiene copolymer rubber (SBR) And various synthetic rubbers such as polybutadiene rubber (BR), acrylonitrile / butadiene copolymer rubber (NBR), and ethylene / propylene / diene copolymer rubber (EPDM).

  The rubber component having an olefinic double bond preferably contains a diene rubber. Here, the diene rubber means a rubber made from a diene monomer having a conjugated double bond. Examples of the diene rubber include natural rubber, modified natural rubber, chloroprene rubber, styrene / butadiene copolymer rubber, polybutadiene rubber, and nitrile rubber. The diene rubber is preferably highly unsaturated, and more preferably natural rubber. It is also effective to use natural rubber in combination with another rubber (for example, styrene / butadiene copolymer rubber or polybutadiene rubber).

  Examples of natural rubber include natural rubber of grades such as RSS # 1, RSS # 3, TSR20, SIR20 and the like. Examples of the epoxidized natural rubber include those having a degree of epoxidation of 10 to 60 mol% (for example, ENR25 and ENR50 manufactured by Kumpoulan Guthrie). As the deproteinized natural rubber, a deproteinized natural rubber having a total nitrogen content of 0.3% by weight or less is preferable. Examples of other modified natural rubbers include, for example, polar groups obtained by reacting natural rubber with 4-vinylpyridine, N, N-dialkylaminoethyl acrylate (for example, N, N-diethylaminoethyl acrylate), 2-hydroxy acrylate, etc. Modified natural rubber.

  Examples of the SBR include emulsion polymerization SBR and solution polymerization SBR described in pages 210 to 211 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Among these, solution polymerization SBR is preferable for the rubber composition for treads.

  Examples of the solution polymerization SBR include a modified solution polymerization SBR obtained by modification with a modifying agent and having at least one element of nitrogen, tin and silicon at the molecular end. Examples of the modifier include lactam compounds, amide compounds, urea compounds, N, N-dialkylacrylamide compounds, isocyanate compounds, imide compounds, silane compounds having an alkoxy group, aminosilane compounds, tin compounds and silane compounds having an alkoxy group. And a combined modifier of an alkyl acrylamide compound and a silane compound having an alkoxy group. These modifiers may be used alone or in combination. Specific examples of the modified solution polymerization SBR include solution polymerization SBR and JSR in which molecular ends are modified using 4,4′-bis (dialkylamino) benzophenone such as “Nipol (registered trademark) NS116” manufactured by Nippon Zeon Co., Ltd. Examples thereof include solution polymerization SBR in which molecular ends are modified using a tin halide compound such as “SL574” manufactured by the company, and silane-modified solution polymerization SBR such as “E10” and “E15” manufactured by Asahi Kasei.

  Oil-extended SBR in which oil such as process oil and aroma oil is added to emulsion polymerization SBR and solution polymerization SBR is also preferable for the rubber composition for tread.

  The BR may be either a solution polymerization BR having a low vinyl content or a solution polymerization BR having a high vinyl content, but a solution polymerization BR having a high vinyl content is preferred. A modified solution polymerization BR having at least one element of nitrogen, tin, or silicon at the molecular end obtained by modification with a modifier is particularly preferred. Examples of the modifier include 4,4′-bis (dialkylamino) benzophenone, tin halide compound, lactam compound, amide compound, urea compound, N, N-dialkylacrylamide compound, isocyanate compound, imide compound, and alkoxy group. Examples thereof include a silane compound having an alkoxy group (for example, a trialkoxysilane compound), an aminosilane compound, a tin compound and a silane compound having an alkoxy group, and a combined modifier having an alkylacrylamide compound and an silane compound having an alkoxy group. These modifiers may be used alone or in combination. Examples of the modified solution polymerization BR include tin-modified BR such as “Nipol (registered trademark) BR 1250H” manufactured by Nippon Zeon.

  BR can be preferably used for a rubber composition for a tread and a rubber composition for a sidewall. BR may be used in a blend with SBR and / or natural rubber (NR). In the rubber composition for a tread, in the rubber component having an olefinic double bond, for example, the amount of SBR and / or NR is 60 to 100% by weight, and the amount of BR is 0 to 40% by weight. In the rubber composition for a sidewall, in the rubber component having an olefinic double bond, the amount of SBR and / or NR is preferably 10 to 70% by weight, and the amount of BR is 30 to 90% by weight, More preferably, the amount of NR is 40 to 60% by weight and the amount of BR is 40 to 60% by weight. For the rubber composition for a tread and the rubber composition for a sidewall, a blend of modified SBR and non-modified SBR, a blend of modified BR and non-modified BR, and the like can be preferably used.

  When the rubber composition is used for tire treads, for example, in passenger car tires, the rubber component having an olefinic double bond uses SBR, which is excellent in wear resistance and hysteresis loss reduction performance, as a base material. In tires, a higher strength NR is optionally used as a base material together with SBR, and it is possible to blend these base materials with BR as necessary to obtain a tread having excellent wear resistance, fatigue resistance, and rebound resilience. Since it is obtained, it is preferable.

  When rubber composition is used for tire sidewall, NR and SBR are blended for passenger car tires, or NR and BR are blended, and NR and BR are blended for truck and bus tires. It is preferable to be used because bending resistance and crack growth resistance are obtained.

  When the rubber composition is used for a tire belt, use of NR and / or IR as a rubber component having an olefinic double bond can provide high elasticity and good adhesion to reinforcing fibers. Therefore, it is preferable.

  When the rubber composition is used as an inner liner of a tire, blending butyl rubber (IIR) with SBR and NR, or blending IIR and NR can improve gas resistance and flex resistance. Since it is obtained, it is preferable.

  As described above, the rubber component having an olefinic double bond preferably includes a diene rubber. The diene rubber is preferably at least one selected from the group consisting of natural rubber (NR), polybutadiene rubber (BR) and styrene / butadiene copolymer rubber (SBR), more preferably (1) NR, (2 ) NR and BR, or (3) SBR. When the diene rubber is used, the amount of the diene rubber in the rubber component having an olefinic double bond is preferably 50% by weight or more, more preferably 60 to 100% by weight, still more preferably 75 to 100% by weight. It is. The rubber component having an olefinic double bond is most preferably made of a diene rubber.

<Carbon black>
Examples of the carbon black include those described in page 494 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Carbon black may use only 1 type and may use 2 or more types together. Specific examples of the carbon black include HAF (High Absorption Furnace), SAF (Super Abrasion Furnace), ISAF (Intermediate SAF), ISAF-HM (Intermediate SAF-High Modulus, FEF (Tax Ax). Furnace), GPF (General Purpose Furnace), and SRF (Semi-Reinforcing Furnace).

The BET specific surface area of carbon black is preferably 10 to 130 m ² / g, more preferably 20 to 130 m ² / g, and still more preferably 40 to 130 m ² / g. This BET specific surface area can be measured by a multipoint nitrogen adsorption method (BET method).

  The amount of carbon black used is preferably 20 to 80 parts by weight, more preferably 30 to 70 parts by weight, and even more preferably 30 to 60 parts by weight with respect to 100 parts by weight of the rubber component having an olefinic double bond. .

<Zinc oxide>
The amount of zinc oxide used is preferably 0.01 to 20 parts by weight, more preferably 0.1 to 15 parts by weight, still more preferably 0.1 to 100 parts by weight of the rubber component having an olefinic double bond. -10 parts by weight.

<Sulfur component>
Examples of the sulfur component include powdered sulfur, precipitated sulfur, colloidal sulfur, insoluble sulfur, and highly dispersible sulfur, morpholine disulfide, and tetramethylthiuram disulfide. Usually, powdered sulfur is preferable, and insoluble sulfur is preferable when the rubber composition is used for manufacturing a tire member having a large amount of sulfur such as a belt member.

  The amount of the sulfur component used is preferably 0.01 to 30 parts by weight, more preferably 0.1 to 20 parts by weight, still more preferably 100 parts by weight of the rubber component having an olefinic double bond. 0.1 to 10 parts by weight.

<Other ingredients>
In this invention, you may use the other component different from the above-mentioned component (The compound (C), the rubber component which has an olefinic double bond, carbon black, a zinc oxide, and a sulfur component). Other components include, for example, a filler different from carbon black, a compound capable of binding to silica, a vulcanization accelerator, a vulcanization accelerator, a resin, a viscoelasticity improver, an anti-aging agent, an oil, a wax, and a chewy. Examples include disintegrators, retarders, compounds having an oxyethylene unit, and catalysts (such as cobalt naphthenate). As for another component, all may use only 1 type and may use 2 or more types together.

  Examples of fillers other than carbon black include silica (for example, hydrous silica), aluminum hydroxide, bituminous coal pulverized product, talc, clay (particularly, calcined clay), and titanium oxide.

Examples of the silica include silica having a CTAB specific surface area of 50 to 180 m ² / g and silica having a nitrogen adsorption specific surface area of 50 to 300 m ² / g. Examples of commercially available silica products include “Nipsil (registered trademark) AQ” and “Nipsil (registered trademark) AQ-N” manufactured by Tosoh Silica Co., Ltd., “Ultrasil (registered trademark) VN3” manufactured by EVONIK, and “Ultrasil (registered trademark)”. (Trademark) VN3-G "," Ultrasil (registered trademark) 360 "," Ultrasil (registered trademark) 7000 "," Zeosil (registered trademark) 115GR "," Zeosil (registered trademark) 1115MP "," Zeosil (registered trademark) "manufactured by Solvay. Trademark) 1205MP "and" Zeosil (registered trademark) Z85MP ". (I) silica having a pH of 6 to 8, (ii) silica containing 0.2 to 1.5% by weight of sodium, (iii) true spherical silica having a roundness of 1 to 1.3, (iv) ) Silicone oil (eg, dimethyl silicone oil), organosilicon compound containing ethoxysilyl group, silica surface-treated with alcohol (eg, ethanol, polyethylene glycol), etc. (v) two or more different nitrogen adsorption specific surface areas Mixtures of silica with can be used as fillers.

Examples of the aluminum hydroxide include aluminum hydroxide having a nitrogen adsorption specific surface area of 5 to 250 m ² / g and a DOP oil supply amount of 50 to 100 ml / 100 g.

  The average particle size of the bituminous coal pulverized product is usually 0.1 mm or less, preferably 0.05 mm or less, more preferably 0.01 mm or less. Even if a bituminous coal pulverized product having an average particle size exceeding 0.1 mm is used, the hysteresis loss of the rubber composition may not be sufficiently reduced, and the fuel efficiency may not be sufficiently improved. Further, when the rubber composition is used as an inner liner composition, the air permeation resistance of the composition may not be sufficiently improved even when a bituminous coal pulverized product having an average particle size exceeding 0.1 mm is used. is there.

  Although the minimum of the average particle diameter of a bituminous coal ground material is not specifically limited, Preferably it is 0.001 mm or more. If it is less than 0.001 mm, the cost tends to increase. The average particle size of the pulverized bituminous coal is a mass-based average particle size calculated from a particle size distribution measured according to JIS Z 8815-1994.

  The specific gravity of the bituminous coal pulverized product is preferably 1.6 or less, more preferably 1.5 or less, and even more preferably 1.3 or less. When a bituminous coal pulverized product having a specific gravity exceeding 1.6 is used, the specific gravity of the entire rubber composition increases, and there is a possibility that the fuel efficiency of the tire cannot be sufficiently improved. The specific gravity of the pulverized bituminous coal is preferably 0.5 or more, and more preferably 1.0 or more. If a bituminous coal pulverized product having a specific gravity of less than 0.5 is used, workability during kneading may be deteriorated.

  When silica is used as the filler, it is preferable to use a compound capable of binding to silica such as a silane coupling agent. Examples of the compound include bis (3-triethoxysilylpropyl) tetrasulfide (eg, “Si-69” manufactured by EVONIK), bis (3-triethoxysilylpropyl) disulfide (eg, “Si— 75 "), bis (3-diethoxymethylsilylpropyl) tetrasulfide, bis (3-diethoxymethylsilylpropyl) disulfide, 3-octanoylthiopropyltriethoxysilane (also known as" octanethioic acid S- [3- ( Triethoxysilyl) propyl] ester ", for example," NXT silane "manufactured by General Electronic Silicons), octanethioic acid S- [3-{(2-methyl-1,3-propanedialkoxy) ethoxysilyl} propyl] ester , Octanethioic acid S- [3-{(2-methyl 1,3-propanedialkoxy) methylsilyl} propyl] ester, methyltrimethoxysilane, methyltriethoxysilane, methyltriacetoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, isobutyltrimethoxysilane, isobutyl Triethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (methoxyethoxy) silane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-amino Propyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, (3-glycidoxypropyl) trimethoxy Silane, (3-glycidoxypropyl) triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- Examples include isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane. Among these, bis (3-triethoxysilylpropyl) tetrasulfide (for example, “Si-69” manufactured by EVONIK), bis (3-triethoxysilylpropyl) disulfide (for example, “Si-75” manufactured by EVONIK) ), 3-octanoylthiopropyltriethoxysilane (for example, “NXT silane” manufactured by General Electronic Silicons) is preferable.

  The addition time of the compound capable of binding to silica is not particularly limited, but it is preferable to add to the rubber component having an olefinic double bond at the same time as silica. When silica and a compound capable of binding to silica are used, the amount of the compound capable of binding to silica is preferably 2 to 10 parts by weight, more preferably 7 to 9 parts by weight with respect to 100 parts by weight of silica. When compounding a compound capable of binding to silica, the compounding temperature is preferably 80 to 200 ° C, more preferably 110 to 180 ° C.

  When silica is used as the filler, monohydric alcohols and polyhydric alcohols may be used together with a compound capable of binding to silica. Examples of the monohydric alcohol include ethanol, butanol, octanol and the like. Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polypropylene glycol, pentaerythritol, and polyether polyol. In the present invention, liquid polybutadiene having molecular ends modified with carboxy or amine may be used.

  Examples of vulcanization accelerators include the thiazole vulcanization accelerators described in pages 412 to 413 of the Rubber Industry Handbook <Fourth Edition> (issued by the Japan Rubber Association on January 20, 1994), Examples thereof include phenamide vulcanization accelerators and guanidine vulcanization accelerators.

  Specific examples of the vulcanization accelerator include N-cyclohexyl-2-benzothiazolylsulfenamide (CBS), N-tert-butyl-2-benzothiazolylsulfenamide (BBS), N, N-dicyclohexene. Examples include xyl-2-benzothiazolylsulfenamide (DCBS), 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), and diphenylguanidine (DPG). Of these, N-cyclohexyl-2-benzothiazolylsulfenamide (CBS) is preferred.

  The ratio of the sulfur component to the vulcanization accelerator is not particularly limited, but the weight ratio of the sulfur component / vulcanization accelerator is preferably 1/10 to 10/1, more preferably 1/5 to 5/1, Preferably it is 1 / 2-2 / 1. In addition, in a rubber member mainly composed of natural rubber, EV vulcanization, which is a method of improving heat resistance, in which the ratio of sulfur component / vulcanization accelerator is 1 or less, is preferably used in applications that particularly require improvement in heat resistance. It is done.

<Other ingredients>

Examples of the vulcanization acceleration aid include stearic acid, citraconic imide compounds, alkylphenol / sulfur chloride condensates, organic thiosulfate compounds, and formula (III):
R ¹⁶ —S—S—R ¹⁷ —S—S—R ¹⁸ (III)
(In the formula, R ¹⁷ represents a C _2-10 alkanediyl group, and R ¹⁶ and R ¹⁸ each independently represents a monovalent organic group containing a nitrogen atom.)
The compound represented by these is mentioned.

  As the vulcanization acceleration aid, stearic acid and citraconic imide compounds are preferable, and stearic acid is more preferable.

  When stearic acid is used, the amount used is preferably 0.01 to 15 parts by weight, more preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the rubber component having an olefinic double bond. Parts, more preferably 0.1 to 5 parts by weight.

  As the citraconimide compound, biscitraconimides are preferable because they are thermally stable and have excellent dispersibility in a rubber component having an olefinic double bond. Specifically, 1,2-biscitraconimidomethylbenzene, 1,3-biscitraconimidomethylbenzene, 1,4-biscitraconimidomethylbenzene, 1,6-biscitraconimidomethylbenzene, 2,3-bis Citraconimidomethyltoluene, 2,4-biscitraconimidomethyltoluene, 2,5-biscitraconimidomethyltoluene, 2,6-biscitraconimidomethyltoluene, 1,2-biscitraconimidoethylbenzene, 1,3-biscitracon Imidoethylbenzene, 1,4-biscitraconimidoethylbenzene, 1,6-biscitraconimidoethylbenzene, 2,3-biscitraconimidoethyltoluene, 2,4-biscitraconimidoethyltoluene, 2,5-biscitraconimidoethyltoluene Emissions, such as 2,6-biscitraconimide ethyltoluene and the like.

  Among citraconic imide compounds, a vulcanized rubber composition that is particularly thermally stable, particularly excellent in dispersibility in a rubber component having an olefinic double bond, and having high hardness (Hs) can be obtained ( 1,3-biscitraconimidomethylbenzene represented by the following formula is preferable for the reason of (reversion suppression).

  Since a vulcanized rubber composition having a high hardness (Hs) can be obtained as a vulcanization acceleration aid, the formula (IV):

[Wherein, n is an integer of 0 to 10, each X is independently an integer of 2 to 4, and each R ¹⁹ is independently a C _5-12 alkyl group. ]
It is preferable to use an alkylphenol-sulfur chloride condensate represented by

  For the reason that the dispersibility of the alkylphenol / sulfur chloride condensate (IV) in the rubber component having an olefinic double bond is good, n is preferably an integer of 1 to 9.

  When X exceeds 4, the alkylphenol-sulfur chloride condensate (IV) tends to become thermally unstable. When X is 1, the sulfur content (sulfur in the alkylphenol-sulfur chloride condensate (IV)) Less weight). X is preferably 2 for the reason that high hardness can be expressed efficiently (reversion suppression).

R ¹⁹ is a C _5-12 alkyl group. R ¹⁹ is preferably a C _6-9 alkyl group because the dispersibility of the alkylphenol-sulfur chloride condensate (IV) in the rubber component having an olefinic double bond is good.

As a specific example of the alkylphenol-sulfur chloride condensate (IV), n is 0 to 10, X is 2, R ¹⁹ is an octyl group, and the sulfur content is 24% by weight. The tack roll V200 is mentioned.

As a vulcanization acceleration aid, a vulcanized rubber composition having high hardness (Hs) can be obtained (reversion suppression).
HO ₃ S—S— (CH ₂ ) _k —S—SO ₃ H (V)
[Wherein, k is an integer of 3 to 10. ]
It is preferable to use a salt of an organic thiosulfate compound represented by the formula (hereinafter sometimes referred to as “organic thiosulfate compound salt (V)”). An organic thiosulfate compound salt (V) containing crystal water may be used. Examples of the organic thiosulfate compound salt (V) include lithium salt, potassium salt, sodium salt, magnesium salt, calcium salt, barium salt, zinc salt, nickel salt, cobalt salt, etc., potassium salt, sodium salt Is preferred.

  k is an integer of 3 to 10, preferably an integer of 3 to 6. When k is 2 or less, there is a tendency that sufficient heat fatigue resistance cannot be obtained. When k is 11 or more, the effect of improving the heat fatigue resistance by the organic thiosulfate compound salt (V) may not be sufficiently obtained. .

  The organic thiosulfate compound salt (V) is preferably a sodium salt monohydrate or a sodium salt dihydrate from the viewpoint of being stable at normal temperature and pressure, and obtained from sodium thiosulfate from the viewpoint of cost. The organic thiosulfate compound salt (V) is more preferable, and 1,6-hexamethylenedithiosulfate sodium dihydrate represented by the following formula is more preferable.

Disperse well in the rubber component having an olefinic double bond, and inserted in the middle of the -S _X -crosslink of the alkylphenol / sulfur chloride condensate (IV) when used in combination with the alkylphenol / sulfur chloride condensate (IV) Because it is possible to form a hybrid bridge with the alkylphenol-sulfur chloride condensate (IV):
R ¹⁶ —S—S—R ¹⁷ —S—S—R ¹⁸ (III)
(In the formula, R ¹⁷ represents a C _2-10 alkanediyl group, and R ¹⁶ and R ¹⁸ each independently represents a monovalent organic group containing a nitrogen atom.)
It is preferable to use the compound represented by these as a vulcanization | cure acceleration | stimulation adjuvant with alkylphenol and sulfur chloride condensate (IV).

R ¹⁷ is a C _2-10 alkanediyl group, preferably a C _4-8 alkanediyl group, and more preferably a linear C _4-8 alkanediyl group. R ¹⁷ is preferably linear. When the carbon number of R ¹⁷ is 1 or less, thermal stability may be poor. If the carbon number of R ¹⁷ is 11 or more, the distance between the polymers via the vulcanization accelerating aid becomes long, and the effect of adding the vulcanization accelerating aid may not be obtained.

R ¹⁶ and R ¹⁸ are each independently a monovalent organic group containing a nitrogen atom. As the monovalent organic group containing a nitrogen atom, those containing at least one aromatic ring are preferred, and those containing an aromatic ring and a ═N—C (═S) — group (thiocarbamoyl group) are more preferred. R ¹⁶ and R ¹⁸ may be the same or different, but are preferably the same for reasons such as ease of production.

  Examples of the compound (III) include 1,2-bis (dibenzylthiocarbamoyldithio) ethane, 1,3-bis (dibenzylthiocarbamoyldithio) propane, 1,4-bis (dibenzylthiocarbamoyldithio) butane. 1,5-bis (dibenzylthiocarbamoyldithio) pentane, 1,6-bis (dibenzylthiocarbamoyldithio) hexane, 1,7-bis (dibenzylthiocarbamoyldithio) heptane, 1,8-bis (di Examples thereof include benzylthiocarbamoyldithio) octane, 1,9-bis (dibenzylthiocarbamoyldithio) nonane, 1,10-bis (dibenzylthiocarbamoyldithio) decane. Of these, 1,6-bis (dibenzylthiocarbamoyldithio) hexane is preferred because it is thermally stable and has excellent dispersibility in a rubber component having an olefinic double bond.

  Examples of commercially available compounds (III) include VULCUREN TRIAL PRODUCT KA9188 and VULCUREN VP KA9188 (1,6-bis (dibenzylthiocarbamoyldithio) hexane) manufactured by Bayer.

  In the present invention, an organic compound such as resorcinol, a resin such as resorcinol resin, modified resorcinol resin, cresol resin, modified cresol resin, phenol resin, and modified phenol resin may be used. By using resorcinol and these resins, the elongation at break and the complex elastic modulus of the vulcanized rubber composition can be improved. Moreover, when using a rubber composition for manufacture of the rubber product which contacts a code | cord | chord, adhesiveness with a code | cord | chord can be improved by using resorcinol and resin.

  Examples of resorcinol include resorcinol manufactured by Sumitomo Chemical Co., Ltd. Examples of the resorcinol resin include resorcinol / formaldehyde condensate. Examples of the modified resorcinol resin include those obtained by alkylating a part of the resorcinol resin repeating unit. Specifically, Penacolite resins B-18-S and B-20 manufactured by Indian Spec, Sumikanol 620 manufactured by Taoka Chemical Industry, R-6 manufactured by Uniroyal, SRF1501 manufactured by Schenectady Chemical, Ash Examples include Arofine 7209 manufactured by Land.

  Examples of the cresol resin include a cresol / formaldehyde condensate. Examples of the modified cresol resin include those obtained by converting the terminal methyl group of the cresol resin into a hydroxy group, and those obtained by alkylating a part of the repeating unit of the cresol resin. Specifically, Sumikanol 610 manufactured by Taoka Chemical Industry Co., Ltd., PR-X11061 manufactured by Sumitomo Bakelite Co., Ltd., and the like can be given.

  As a phenol resin, a phenol-formaldehyde condensate is mentioned, for example. Examples of modified phenolic resins include resins obtained by modifying phenolic resins with cashew oil, tall oil, linseed oil, various animal and vegetable oils, unsaturated fatty acids, rosin, alkylbenzene resins, aniline, melamine, and the like.

  Examples of other resins include methoxylated methylol melamine resins such as “Sumikanol 507AP” manufactured by Sumitomo Chemical Co., Ltd .; Coumarone resin NG4 (softening point 81 to 100 ° C.) manufactured by Nippon Steel Chemical Co., Ltd. Coumarone-indene resin such as “Process Resin AC5” (softening point 75 ° C.); Terpene resins such as terpene resin, terpene / phenol resin, and aromatic modified terpene resin; “Nicanol® A70” manufactured by Mitsubishi Gas Chemical Company, Inc. ”(Softening point 70-90 ° C.), etc .; hydrogenated rosin derivatives; novolac alkylphenol resins; resol alkylphenol resins; C5 petroleum resins; liquid polybutadiene.

  Examples of the anti-aging agent include those described in pages 436 to 443 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Anti-aging agents include N-phenyl-N′-1,3-dimethylbutyl-p-phenylenediamine (abbreviation “6PPD”, for example, “Antigen (registered trademark) 6C” manufactured by Sumitomo Chemical Co., Ltd.), reaction of aniline and acetone. Products (abbreviated as “TMDQ”), poly (2,2,4-trimethyl-1,2-) dihydroquinoline) (for example, “Antioxidant FR” manufactured by Matsubara Sangyo Co., Ltd.), synthetic wax (paraffin wax, etc.), plant A wax is preferably used.

  When using an antioxidant, the amount used is preferably 0.01-15 parts by weight, more preferably 0.1-10 parts per 100 parts by weight of the rubber component having an olefinic double bond. Part by weight, more preferably 0.1 to 5 parts by weight.

  Examples of the oil include process oil and vegetable oil. Examples of the process oil include paraffinic process oil, naphthenic process oil, and aromatic process oil. Examples of commercially available products include aromatic oil (“NC-140” manufactured by Cosmo Oil Co., Ltd.) and process oil (“Diana Process PS32” manufactured by Idemitsu Kosan Co., Ltd.).

  Examples of the wax include “Sannok (registered trademark) wax” manufactured by Ouchi Shinsei Chemical Co., Ltd. and “OZOACE-0355” manufactured by Nippon Seiwa Co., Ltd.

  The peptizer is not particularly limited as long as it is usually used in the rubber field. For example, it is described in pages 446 to 449 of the “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. And aromatic mercaptan peptizers, aromatic disulfide peptizers, and aromatic mercaptan metal salt peptizers. Among them, dixylyl disulfide and o, o'-dibenzamide diphenyl disulfide ("Noctizer SS" manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.) are preferable. Only one type of peptizer may be used, or two or more types may be used in combination.

  Examples of the retarder include phthalic anhydride, benzoic acid, salicylic acid, N-nitrosodiphenylamine, N- (cyclohexylthio) phthalimide (CTP), sulfonamide derivatives, diphenylurea, bis (tridecyl) pentaerythritol diphosphite, and the like. (Cyclohexylthio) phthalimide (CTP) is preferably used.

In the present invention, the formula: —O— (CH ₂ —CH ₂ —O) _q —H [wherein q is an integer of 1 or more. You may use the compound which has an oxyethylene unit which has a structure represented by this. Here, in the above formula, q is preferably 2 or more, and more preferably 3 or more. Moreover, q is preferably 16 or less, and more preferably 14 or less. When q is 17 or more, compatibility with a rubber component having an olefinic double bond and reinforcing properties tend to be lowered.

  The position of the oxyethylene unit in the compound having an oxyethylene unit may be a main chain, a terminal, or a side chain. Of the compounds having oxyethylene units, a compound having oxyethylene units at least in the side chain is preferred from the viewpoint of sustaining the effect of preventing static electricity accumulation on the obtained tire surface and reducing electric resistance.

  Examples of the compound having an oxyethylene unit in the main chain include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, monoethylene glycol, diethylene glycol, triethylene glycol, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene polyoxypropylene Examples thereof include alkyl ethers, polyoxyethylene alkylamines, polyoxyethylene styrenated alkyl ethers, and polyoxyethylene alkyl amides.

  When using a compound having an oxyethylene unit at least in the side chain, the number of oxyethylene units is preferably 4 or more, more preferably 8 or more per 100 carbon atoms constituting the main chain. When the number of oxyethylene units is 3 or less, the electrical resistance tends to increase. The number of oxyethylene units is preferably 12 or less, and more preferably 10 or less. When the number of oxyethylene units is 13 or more, the compatibility with the rubber component having an olefinic double bond and the reinforcing property tend to be lowered.

  The main chain of the compound having an oxyethylene unit at least in the side chain is preferably composed mainly of polyethylene, polypropylene or polystyrene.

<Manufacturing method>
(1) Manufacturing method of rubber composition The method of the present invention comprises:
The compound (C), a rubber component having an olefinic double bond (hereinafter sometimes abbreviated as “rubber component”), and carbon black are kneaded to obtain a kneaded product. Step 2 of kneading the kneaded product and zinc oxide to obtain a rubber composition
It is characterized by including.

  As described above, the compound (C), the rubber component, the carbon black, and the zinc oxide are mixed at once by mixing the zinc oxide with the zinc oxide after the compound (C), the rubber component, and the carbon black. The loss factor (tan δ) of the vulcanized rubber composition can be reduced as compared with the case of kneading.

  From the viewpoint of reducing the loss factor (tan δ) of the vulcanized rubber composition, it is preferable to knead the entire amount of the compound (C) used in the present invention in Step 1. However, you may knead | mix partly the usage-amount of the compound (C) in this invention in the process 2 in the range which does not impair the effect of this invention greatly. The amount of the compound (C) to be kneaded in Step 2 is preferably 0 to 25% by weight, more preferably 0 to 10% by weight in the amount used in the present invention.

  From the viewpoint of reducing the loss factor (tan δ) of the vulcanized rubber composition, it is preferable to knead the entire amount of the rubber component used in the present invention in Step 1. However, you may knead | mix part of the usage-amount of the rubber component in this invention in the process 2 in the range which does not impair the effect of this invention significantly. The amount of the rubber component kneaded in step 2 is preferably 0 to 50% by weight, more preferably 0 to 40% by weight, based on the amount used in the present invention.

  From the viewpoint of reducing the loss factor (tan δ) of the vulcanized rubber composition, it is preferable to knead the entire amount of carbon black used in the present invention in Step 1. However, part of the amount of carbon black used in the present invention may be kneaded in step 2 within a range that does not significantly impair the effects of the present invention. The amount of carbon black kneaded in step 2 is preferably 0 to 75% by weight, more preferably 0 to 25% by weight, based on the amount used in the present invention.

  From the viewpoint of reducing the loss factor (tan δ) of the vulcanized rubber composition, it is preferable to knead the entire amount of zinc oxide used in the present invention in step 2. However, you may knead | mix partly the usage-amount of the zinc oxide in this invention in the process 1 in the range which does not impair the effect of this invention greatly. The amount of zinc oxide kneaded in step 2 is preferably 0 to 25% by weight, more preferably 0 to 10% by weight, based on the amount used in the present invention.

  In the present invention, in order to facilitate the processing of the rubber component, a pre-kneading step of masticating the rubber component may be provided before step 1. When a peptizer is used, it is preferable that all of the amount used in the present invention is kneaded in the preliminary kneading step, or a part of the amount used is kneaded in the preliminary kneading step, and the rest is kneaded in step 1. .

  Hereinafter, “the step of kneading the sulfur component” is described as “pro step”, “the step of not kneading the sulfur component” is described as “non-pro step”, and “the rubber composition obtained after the pro step” The method of the present invention will be described by describing as “a rubber composition containing a sulfur component”. In the method of the present invention, the kneaded product obtained in step 1, the zinc oxide, and the sulfur component may be kneaded in step 2. That is, in the method of the present invention, a compound (C), a rubber component, carbon black, and other components as necessary are kneaded in a non-pro step (= step 1) to produce a kneaded product. The obtained kneaded product, zinc oxide, sulfur component, and other components as necessary may be kneaded in a pro step (= step 2) to produce a rubber composition.

In the method of the present invention, the non-pro step is divided into two steps. First, the compound (C), a rubber component, carbon black, and other components as necessary are added to the non-pro first step. (= Step 1) kneaded to produce a kneaded product, and the obtained kneaded product, zinc oxide, and if necessary, other components are kneaded in the non-pro second step (= step 2). A rubber composition is prepared, and the resulting rubber composition, a sulfur component, and other components as necessary are kneaded in a pro step (= step 3) to produce a rubber composition containing a sulfur component. May be.
Hereinafter, the preliminary kneading step, the non-pro step, and the pro step will be described in order.

(A) Pre-kneading step As described above, in the method of the present invention, a pre-kneading step of kneading the rubber component may be performed. For the kneading in the preliminary kneading step, for example, an internal mixer including a Banbury mixer, an open kneader, a pressure kneader, an extruder, and an injection molding machine can be used.

  The rotational speed for mastication in the preliminary kneading step is preferably 5 to 100 rpm, more preferably 10 to 80 rpm, and still more preferably 10 to 60 rpm. The kneading time for kneading is preferably 0.5 to 15 minutes, more preferably 1 to 10 minutes, and further preferably 1 to 4 minutes.

(B) Non-pro process For kneading in the non-pro process, for example, an internal mixer including a Banbury mixer, an open kneader, a pressure kneader, an extruder, and an injection molding machine can be used.

  The kneading in the non-pro process may be performed by changing the rotation speed. For example, first, kneading may be performed at a low first rotation speed, and then kneading may be performed at a second rotation speed higher than the first rotation speed. The first rotation speed is preferably 2 to 35 rpm, more preferably 4 to 25 pm, still more preferably 6 to 15 rpm, and the kneading time is preferably 0.5 to 5 minutes, more preferably 0.5 to 3 minutes, more preferably 0.5 to 2 minutes. The second rotation speed is preferably 35 to 100 rpm, more preferably 40 to 90 pm, further preferably 45 to 80 rpm, and the kneading time is preferably 1 to 10 minutes, more preferably 1.5 to 8 minutes. More preferably, it is 2 to 6 minutes.

  The discharge temperature of the kneaded material from the apparatus used in the non-pro process is preferably 120 to 180 ° C, more preferably 130 to 170 ° C, and still more preferably 140 to 160 ° C.

(C) Cooling step In the method of the present invention, the kneaded product obtained in the non-pro step may be cooled. Examples of the cooling operation of the kneaded product include natural cooling, water cooling, and forced air cooling. Among these, simple cooling is preferable.

  In order to promote cooling (particularly, cooling), the kneaded material obtained in the non-pro process may be processed into a sheet or board using an open roll. The thickness of the kneaded material processed into a sheet or board is preferably 0.5 to 20 mm, more preferably 2 to 10 mm.

(D) Pro process For the kneading of the rubber composition obtained as described above and the sulfur component, for example, an open roll, a calender, or the like can be used. The kneading temperature in the pro step (the temperature of the rubber composition being kneaded) is preferably 20 to 100 ° C, more preferably 30 to 90 ° C, and further preferably 40 to 80 ° C.

  When using a vulcanization accelerator, it is preferable to knead the entire amount used in the pro process. Moreover, when using a retarder, it is preferable to knead | mix the whole usage-amount in a pro process.

(2) Method for producing vulcanized rubber composition A vulcanized rubber composition can be produced by vulcanizing a rubber composition containing a sulfur component. The vulcanization temperature is preferably 120 to 180 ° C. A person skilled in the art can appropriately set the vulcanization time according to the composition of the rubber composition. Vulcanization is usually carried out at normal pressure or under pressure.

<Rubber composition and vulcanized rubber composition>
The present invention also provides a rubber composition and a vulcanized rubber composition obtained by the above-described method. In this regard, as shown in the examples and comparative examples described later, the loss factor (tan δ) of the vulcanized rubber composition obtained by the method of the present invention including the step 1 and the step 2 is the compound (C), Compared to the loss factor of a vulcanized rubber composition obtained by a method including a step of kneading a rubber component, carbon black, and zinc oxide all at once (hereinafter sometimes referred to as “other method”). Low. Therefore, it is clear that the rubber composition and vulcanized rubber composition obtained by the method of the present invention are different from the rubber composition and vulcanized rubber composition obtained by other methods.

  However, it is a current analytical technique to distinguish the rubber composition obtained by the method of the present invention from the rubber composition obtained by other methods that differ only in operation and use the same components. Impossible or approximately impractical. In other words, with the current technology for analyzing a solid rubber composition, it is impossible or almost impractical to directly identify the rubber composition obtained by the method of the present invention by its structure or the like. . Therefore, in the present specification and claims, the rubber composition and vulcanized rubber composition of the present invention are specified by the method of the present invention.

  Hereinafter, the present invention will be described more specifically with reference to examples and the like. However, the present invention is not limited by the following examples, and appropriate modifications are made within a range that can meet the above and the following purposes. Any of these can be carried out and are included in the technical scope of the present invention.

<Ingredients>
Components and abbreviations in the following examples and the like are as follows.
・ NR: Natural rubber (RSS # 1)
・ BR: Polybutadiene rubber (product name “BR01” manufactured by JSR)
SBR: emulsion-polymerized styrene / butadiene copolymer rubber (manufactured by JSR, trade name “JSR 1502”)
GPF-CB: Carbon black GPF (Asahi Carbon Co., Ltd., trade name “Asahi # 55”, BET specific surface area: 26 m ² / g)
HAF-CB: carbon black HAF (manufactured by Asahi Carbon Co., Ltd., trade name “Asahi # 70”, BET specific surface area: 77 m ² / g)
SAF-CB: Carbon black SAF (manufactured by Tokai Carbon Co., Ltd., trade name “SEAST 9”, BET specific surface area: 142 m ² / g)
Compound (Ia-1): (2Z) -4-[(4-aminophenyl) amino] -4-oxo-2-butenoate sodium dihydrate Compound (II-1): S- (3 -Aminopropyl) thiosulfuric acid / zinc oxide (ZnO)
・ Stearic acid (trade name “Lunac S20” manufactured by Kao Corporation)
Anti-aging agent: N-phenyl-N′-1,3-dimethylbutyl-p-phenylenediamine (manufactured by Ouchi Shinsei Co., Ltd., trade name “Antigen (registered trademark) 6C”)
・ Sulfur component: Powdered sulfur (S8)
・ Vulcanization accelerator: N-cyclohexyl-2-benzothiazolylsulfenamide (CBS)

<Examples 1-6 and Comparative Examples 1-6>
The rubber composition of Examples 1-6 and Comparative Examples 1-6, the rubber composition containing a sulfur component, and the vulcanized rubber composition were manufactured as follows.

The rubber components of the types and amounts shown in the table below were charged into a Banbury mixer (BB2 manufactured by Kobe Steel) set to a temperature of 80 ° C. at the start of the pre-kneading step and the non-pro step kneading, and then 2 at a rotation speed of 50 rpm. I kneaded. Add components other than rubber components in the types and amounts shown in the table below, knead for 2 minutes at 10 rpm, then knead for 2 minutes at 50 rpm, and discharge the kneaded product did. The discharge temperature of the kneaded product in the non-pro process was about 145 ° C.

The kneaded product obtained in the cooling step non-pro step is processed into a sheet having a thickness of 3 to 5 mm using an open roll (laboratory mill manufactured by Kansai Roll Co., Ltd.) having a set temperature of 50 ° C. Until it becomes, the sheet-like kneaded material was allowed to cool in an air atmosphere at room temperature.

The kneaded product (described as “kneaded product” in the following table) after the cooling step and the components of the types and amounts shown in the following table are kneaded at a temperature of 60 to 80 ° C. with a pro process open roll, and sulfur A rubber composition containing the components was obtained.

Vulcanization process Using a vulcanizing press, set the vulcanization temperature to 145 ° C, and set the vulcanization time to the value of t (90) obtained by rheometer measurement according to JIS K 6300-2, 10 minutes. The vulcanized rubber composition was obtained by vulcanizing the rubber composition obtained in the pro process with the time set to.

  As shown in the following table, in Comparative Examples 1 to 6, zinc oxide was kneaded in the non-pro process, and in Examples 1 to 6, zinc oxide was not kneaded in the non-pro process, and zinc oxide was mixed in the pro process. Kneaded.

Calculation of relative value of tan δ The viscoelastic properties of the vulcanized rubber compositions obtained in Examples 1 to 6 and Comparative Examples 1 to 6 were measured using a viscoelastic analyzer manufactured by Ueshima Seisakusho Co., Ltd. under the following conditions. The loss coefficient (tan δ) at 60 ° C. was obtained.
Measurement temperature: 60 ° C
Initial strain: 10%
Dynamic strain: 2.5%
Frequency: 10Hz

In Example 1, the relative value of tan δ was calculated based on tan δ of the vulcanized rubber composition of Comparative Example 1. Specifically, using tan δ measured as described above, the following formula:
Relative value of tan δ = 100 × (tan δ of the vulcanized rubber composition of Example 1) / (tan δ of the vulcanized rubber composition of Comparative Example 1)
From the above, the relative value of tan δ with the tan δ value of the vulcanized rubber composition of Comparative Example 1 being 100 was calculated.

  Similar to Example 1, Example 2 is based on tan δ of the vulcanized rubber composition of Comparative Example 2, Example 3 is based on tan δ of the vulcanized rubber composition of Comparative Example 3, and Example 4 is a comparative example. Example 5 is based on tan δ of the vulcanized rubber composition, Example 5 is based on tan δ of the vulcanized rubber composition of Comparative Example 5, and Example 6 is based on tan δ of the vulcanized rubber composition of Comparative Example 6. Thus, the relative value of tan δ was calculated. The results are shown in the table below.

  As shown in the above table, in Examples 1 to 6, the rubber component, carbon black, and compound (Ia-1) were kneaded in a non-pro process, and the obtained kneaded material and zinc oxide were pro Kneaded in the process. On the other hand, in Comparative Examples 1 to 6, compound (Ia-1), rubber component, carbon black, and zinc oxide were kneaded at a time in a non-pro process. In Examples 1 to 6, the relative values of tan δ relative to Comparative Examples 1 to 6 are all smaller than 100. From these results, it can be seen that tan δ of the vulcanized rubber composition can be reduced by the present invention.

<Examples 7 to 24>
The pre-kneading process and the non-pro process Banbury mixer (BB2 manufactured by Kobe Steel, set temperature at the start of kneading: 80 ° C.) were charged with the rubber components of the types and amounts shown in the table below, and the rotation speed was 50 rpm for 2 minutes. Knead. By adding components other than rubber components in the types and amounts shown in the following table, kneading for 2 minutes at a rotation speed of 10 rpm, and then kneading for 2 minutes at a rotation speed of 50 rpm, a kneaded product Is obtained.

Cooling step The kneaded product is processed into a sheet having a thickness of 3 to 5 mm using an open roll (laboratory mill manufactured by Kansai Roll Co., Ltd.) having a set temperature of 50 ° C., and then brought to room temperature in a room temperature atmosphere. By allowing to cool, a sheet-like kneaded product is obtained.

By kneading a sheet-like kneaded material (described as “kneaded material” in the table below) and components of the types and amounts shown in the table below at a temperature of 60 to 80 ° C. in a pro process open roll. A rubber composition containing the components is obtained.

Vulcanization process Using a vulcanizing press machine, the vulcanization temperature is set to 145 ° C., and the vulcanization time is “value of t (90) obtained by rheometer measurement according to JIS K 6300-2 + 10 minutes” The vulcanized rubber composition is obtained by vulcanizing the rubber composition containing the sulfur component.

  According to the method of the present invention, a vulcanized rubber composition having a low loss factor can be produced. The rubber composition obtained by the method of the present invention is useful for production of various products (for example, vulcanized tires and tire members).

Claims (7)

A compound (C) having a group or structure (A) capable of reacting with an olefinic double bond and a group or structure (B) capable of reacting or interacting with carbon black, and a rubber component having an olefinic double bond; Step 1 for kneading carbon black to obtain a kneaded product, and Step 2 for kneading the kneaded product obtained in Step 1 and zinc oxide to obtain a rubber composition
The manufacturing method of the rubber composition containing this. Compound (C) is represented by formula (I):

[In the formula (I),
R ¹ is a C _2-12 alkanediyl group that may have one or more substituents, a C _3-10 cycloalkanediyl group that may have one or more substituents, and one or more substituents. It represents a divalent C _6-12 aromatic hydrocarbon group which may have a hydrogen atom, or a combination thereof.
R ² and R ³ each independently have a hydrogen atom, a halogen atom, a hydroxy group, one or more C _1-6 alkoxy group which may have one or more substituents, and one or more substituents. Represents a good C _1-6 alkyl group, or a C _6-14 aryl group optionally having one or more substituents, or R ² and R ³ are bonded, and the carbon atom to which they are bonded; Together, they form a C _3-10 cycloalkenediyl group that may have one or more substituents.
R ⁴ is a hydroxy group, a C _1-6 alkoxy group optionally having one or more substituents, a C _6-14 aryloxy group optionally having one or more substituents, or —NR ^5. R ⁶ (wherein R ⁵ and R ⁶ each independently represents a hydrogen atom or a C _1-6 alkyl group which may have one or more substituents).
X represents -NH- or -O-. ]
And its salts, solvates and solvates thereof, and formula (II):

[In the formula (II),
R ⁷ and R ⁸ each independently represent a hydrogen atom or a C _1-6 alkyl group which may have one or more substituents, or R ⁷ and R ⁸ are bonded to each other to form one or more substituents. A C _2-12 alkanediyl group which may have a group is formed.
m represents an integer of 2 to 9.
n represents 1 or 2.
M ^{n +} represents H ⁺ or an n-valent metal ion. ]
The method according to claim 1, which is at least one selected from the group consisting of compounds represented by:   The method according to claim 1 or 2, wherein the kneaded product obtained in step 1, the zinc oxide, and the sulfur component are kneaded in step 2 to obtain a rubber composition.   The manufacturing method of Claim 1 or 2 which further includes the process 3 which knead | mixes the rubber composition obtained by the process 2, and a sulfur component, and obtains a rubber composition.   A method for producing a vulcanized rubber composition, comprising vulcanizing the rubber composition obtained by the method according to claim 3.   The rubber composition obtained by the method as described in any one of Claims 1-4.   A vulcanized rubber composition obtained by the method according to claim 5.