JP6047140B2 - Rubber composition and pneumatic tire - Google Patents

Description

The present invention relates to a rubber composition and a pneumatic tire using the same.

Carbon black has a great influence on the performance of the rubber composition when blended in the rubber composition due to physical properties such as specific surface area, structure and surface properties. For this reason, carbon black having different characteristics is selectively used depending on the required performance of the rubber composition, the environmental conditions in which the rubber composition is used, and the like (for example, Patent Document 1).

The tread rubber that is in contact with the ground is required to have excellent resistance to wear during running (wear resistance), low hysteresis loss that occurs when the rubber is running, and low heat build-up. In order to achieve both wear resistance and low heat build-up, methods such as a high filling method of carbon black, a high specific surface area (small particle size), or a method using carbon black having a high structure are being studied. However, when these carbon blacks are used, although the wear resistance is improved, the low heat build-up may not be sufficient.

In addition, as a technique for improving the wear resistance of a tire with characteristics other than the specific surface area and structure of carbon black, a technique for increasing the sharpness of the aggregate diameter distribution of carbon black has been proposed. However, the rubber composition in which the carbon black is blended has reduced heat build-up, and the low heat build-up of a tire using the rubber composition as a tread may not be sufficient. Further, if the sharpness of the aggregate diameter distribution is lowered (increases the broadness), the low heat buildup of the tire can be improved, but at the same time, the wear resistance tends to be lowered. Thus, the method of adjusting only the aggregate diameter distribution of carbon black is not an effective means for achieving both wear resistance and low heat build-up of the tire.

On the other hand, Patent Document 2 proposes a technique for improving the dispersibility of carbon black by adding a diamine-based compound and improving low heat generation. However, there is still room for improvement in terms of improving low heat buildup while maintaining good wear resistance. Furthermore, there was room for further improvement in terms of workability.

Thus, wear resistance and low heat build-up are in a trade-off relationship, and developments are being made to achieve both performances at a high level, but there is still room for improvement.

JP 2001-081239 A Japanese Patent No. 2912845

An object of the present invention is to solve the above-mentioned problems and to provide a rubber composition capable of achieving both wear resistance and low heat buildup while maintaining good processability, and a pneumatic tire using the same. .

As a result of intensive studies, the present inventors have formulated a rubber composition with carbon black having a specific aggregate characteristic, such as carbon black obtained using a specific raw material oil, thereby reducing wear resistance and reducing the wear resistance. We found that it is possible to achieve both exothermic properties, and furthermore, by combining the carbon black with a specific amphoteric compound, we found that it is possible to synergistically improve wear resistance and low exothermicity while maintaining good processability. The present invention has been completed.
That is, the present invention relates to a rubber composition comprising a rubber component, one or more amphoteric compounds, and one or more carbon blacks, wherein the amphoteric compounds are carboxylic acid groups, sulfonic acid groups, phosphoric acid groups, thiosulfones. An acidic functional group which is at least one functional group selected from the group consisting of an acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group; It has a basic functional group which is an amino group or a substituted amino group, and at least one of the carbon blacks has an average boiling point T (° C) and 60 ° F as a raw material oil for producing the carbon black. A feedstock having a BMCI value of 150 or less and an aliphatic hydrocarbon ratio of 30% by mass or more calculated from the specific gravity D (60/60 ° F.) when compared with water. The rubber composition is a carbon black obtained using about.
BMCI = 48640 / (T + 273) + 473.7D-456.8

The amphoteric compound is preferably a compound represented by the following formula (I).

In the above formula (I), ^{R 1} represents an alkylene group, alkenylene group or alkynylene group having 2 to 30 carbon atoms. A is selected from the group consisting of a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group. Represents an acidic functional group that is at least one functional group. R ² and R ³ are the same or different and are a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, or an alkyl group having 1 to 20 carbon atoms. Represents an alkoxysilyl group. The compound represented by the above formula (I) may be a metal salt of the compound.

The amphoteric compound is preferably a compound represented by the following formula (I-1) and / or the following formula (I-2).

In said formula (I-1), p represents the integer of 2-8. In said formula (I-2), q represents the integer of 2-8. M ^{r +} represents a metal ion, and r represents its valence.

The metal ion represented by ^{Mr +} in the above formula (I-2) is preferably a lithium ion, a sodium ion, a potassium ion, a cesium ion, a cobalt ion, a copper ion, or a zinc ion.

It is also preferable that the amphoteric compound is at least one selected from the group consisting of (A1), (B1), (C1) and (D1).
(A1): Compound (B1) represented by the following formula (II): Salt (C1) of the compound represented by the following formula (II): Solvate (D1) of the compound represented by the following formula (II) ): Solvate of the salt of the compound represented by the following formula (II)

In the above formula (II), R ¹¹ is an optionally substituted alkanediyl group having 2 to 12 carbon atoms, an optionally substituted cycloalkanediyl group having 3 to 12 carbon atoms, or * —B ¹ —Ar—B ² — * group, and * represents a bond. B ¹ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms. B ² represents a single bond or an alkanediyl group having 1 to 12 carbon atoms. Ar represents a C6-C12 divalent aromatic hydrocarbon group which may have a substituent. R ¹² and R ¹³ are the same or different and each represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxy group, or an alkoxy group having 1 to 6 carbon atoms. Alternatively, they are bonded to each other to form an alkanediyl group having 2 to 12 carbon atoms. R ¹⁴ represents a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylalkoxy group having 7 to 15 carbon atoms, or —NR ¹⁵ R ¹⁶ , wherein R ¹⁵ and R ¹⁶ are These are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X represents -NH- or -O-.

R ¹² and R ¹³ in the above formula (II) are preferably hydrogen atoms.

The compound represented by the above formula (II) is preferably a compound represented by the following formula (III).

In said formula (III), R < ¹¹ >, R < ¹² >, R <^13> , R <^14> and X represent the same meaning as the above.

R ¹¹ is preferably a C 6-12 divalent aromatic hydrocarbon group which may have a substituent, and X is preferably —NH—.

R ¹⁴ is preferably a hydroxy group.

The content of the amphoteric compound is preferably 0.01 to 30 parts by mass with respect to 100 parts by mass of carbon black.

Carbon obtained by using at least one of the carbon blacks as a raw material oil for producing the carbon black, a raw material oil having a BMCI value of 95 or more and an aliphatic hydrocarbon ratio of 60% by mass or less Black is preferred.

In 100% by mass of aliphatic hydrocarbons contained in the raw material oil, 10% by mass or more is preferably an aliphatic hydrocarbon derived from animal or vegetable oils or modified products thereof.

The raw material oil preferably contains tall oil.

At least one of the carbon blacks is preferably carbon black produced by a furnace method.

The present invention also provides a rubber composition comprising a rubber component, one or more amphoteric compounds, and one or more carbon blacks, wherein the amphoteric compound is a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, or a thiosulfonic acid. An acidic functional group that is at least one functional group selected from the group consisting of a group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group; Having a basic functional group which is a group or a substituted amino group, and at least one of the above carbon blacks has a maximum frequency diameter (Dmod) of a Stokes equivalent diameter distribution curve as an aggregate characteristic of 79 nm or less, a distribution curve with respect to Dmod It is related with the rubber composition which is carbon black whose ratio ((DELTA) D50 / Dmod) of half width ((DELTA) D50) of this is 0.78 or more.

The rubber composition is preferably used as a tire rubber composition.

The present invention also relates to a pneumatic tire produced using the rubber composition.

According to the present invention, since the rubber composition includes a rubber component, an amphoteric compound having a specific acidic functional group and a specific basic functional group, and a specific carbon black, it is possible to maintain good processability. In addition, it is possible to provide a pneumatic tire that can achieve both wear resistance and low heat buildup and that both performances are synergistically improved.

1st this invention is a rubber composition containing a rubber component, 1 or more types of amphoteric compounds, and 1 or more types of carbon black, The said amphoteric compounds are a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, An acidic functional group that is at least one functional group selected from the group consisting of a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group, and , Having a basic functional group that is an amino group or a substituted amino group, and at least one of the carbon blacks has an average boiling point T (° C.) and 60 ° F. as a raw material oil for producing the carbon black. Using a feedstock oil having a BMCI value of 150 or less and an aliphatic hydrocarbon ratio of 30% by mass or more calculated from the specific gravity D (60/60 ° F.) compared to And it relates to a rubber composition which is obtained carbon black (1).
BMCI = 48640 / (T + 273) + 473.7D-456.8

The second aspect of the present invention is a rubber composition comprising a rubber component, one or more amphoteric compounds, and one or more carbon blacks, wherein the amphoteric compound is a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, An acidic functional group that is at least one functional group selected from the group consisting of a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group, and A basic functional group that is an amino group or a substituted amino group, and at least one of the carbon blacks has a maximum frequency diameter (Dmod) of a Stokes equivalent diameter distribution curve as an aggregate characteristic of 79 nm or less, with respect to Dmod. The present invention relates to a rubber composition which is carbon black (1) having a ratio of half width (ΔD50) of distribution curve (ΔD50 / Dmod) of 0.78 or more. That.

In the present invention, Dmod is a raw material oil for producing carbon black, such as carbon black (1) obtained by using a raw material oil having a BMCI value of a specific value or less and an aliphatic hydrocarbon ratio of a specific value or more. Wear resistance can be improved while maintaining or improving good low heat build-up by blending the rubber composition with carbon black having specific aggregate characteristics that are below a specific value and ΔD50 / Dmod is above a specific value. Further, it is possible to achieve both high wear resistance and low heat generation. Furthermore, in the present invention, in addition to the specific carbon black, an amphoteric compound having a specific acidic functional group and a specific basic functional group is blended to maintain good processability while maintaining wear resistance and low heat generation. Sex can be improved synergistically.

Examples of rubber components that can be used in the present invention include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SBR), styrene isoprene butadiene rubber (SIBR), and chloroprene rubber (CR). And diene rubbers such as acrylonitrile butadiene rubber (NBR), ethylene propylene diene rubber (EPDM), butyl rubber (IIR), and halogenated butyl rubber (X-IIR). A rubber component may be used independently and may use 2 or more types together. Among these, NR is preferable from the viewpoint of low heat generation and mechanical strength, BR is preferable from the viewpoint of wear resistance and bending crack resistance, and SBR is preferable from the viewpoint of wet grip performance. Furthermore, it is more preferable to use NR and BR together because the wear resistance and low heat build-up when used in a tire can be improved in a balanced manner.

The NR is not particularly limited, and for example, those commonly used in the tire industry such as SIR20, RSS # 3, TSR20 can be used.

The content of NR in 100% by mass of the rubber component is preferably 20% by mass or more, more preferably 30% by mass or more, and further preferably 40% by mass or more. If it is less than 20% by mass, sufficient rubber strength and low exothermicity tend not to be obtained. The upper limit of the content of NR is not particularly limited, and may be 100% by mass. However, when other rubber components are used together with NR, 70% by mass or less is preferable.

It is not particularly limited as BR, for example, BR1220 manufactured by Nippon Zeon Co., Ltd., BR130B manufactured by Ube Industries, Ltd., BR150B having high cis content such as BR150B, VCR412 manufactured by Ube Industries, Ltd., VCR617, etc. BR containing syndiotactic polybutadiene crystals can be used. Among these, from the reason that the wear resistance is good, the cis content of BR is preferably 90% by mass or more, and more preferably 95% by mass or more.
The cis content of BR can be measured by infrared absorption spectrum analysis.

The content of BR in 100% by mass of the rubber component is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 20% by mass or more. If it is less than 5% by mass, sufficient wear resistance may not be obtained. The BR content is preferably 70% by mass or less, more preferably 60% by mass or less.

The SBR is not particularly limited, and those generally used in the tire industry such as emulsion polymerization styrene butadiene rubber (E-SBR) and solution polymerization styrene butadiene rubber (S-SBR) can be used.

The content of SBR in 100% by mass of the rubber component is preferably 5% by mass or more, more preferably 10% by mass or more. If it is less than 5% by mass, sufficient wet grip performance cannot be obtained, and low heat build-up and wear resistance may not be improved. The content of SBR is preferably 50% by mass or less, more preferably 35% by mass or less.

The total content of NR and BR in 100% by mass of the rubber component is preferably 60% by mass or more, more preferably 80% by mass or more, and may be 100% by mass. When the total content of NR and BR is within the above range, the effect of the present invention can be more suitably obtained.

In the present invention, the carbon black (1) is used. By blending the carbon black (1), both wear resistance and low heat build-up can be achieved.

In the second aspect of the present invention, the maximum frequency diameter (Dmod) of the distribution curve of the Stokes equivalent diameter as the aggregate characteristic of the carbon black (1) is 79 nm or less, preferably 69 nm or less, more preferably 63 nm or less. If it exceeds 79 nm, the effect of the present invention (particularly, the effect of improving wear resistance) cannot be obtained sufficiently. Although the minimum of this Dmod is not specifically limited, Preferably it is 40 nm or more, More preferably, it is 50 nm or more, More preferably, it is 56 nm or more. If it is less than 40 nm, the dispersibility is inferior, and the fracture characteristics and wear resistance tend to decrease.

In the second aspect of the present invention, the ratio (ΔD50 / Dmod) of the half width (ΔD50) of the distribution curve to Dmod as the aggregate characteristic of carbon black (1) is 0.78 or more, preferably 0.90. As mentioned above, More preferably, it is 1.0 or more, More preferably, it is 1.1 or more. If it is less than 0.78, the effect of the present invention (particularly, the effect of improving low heat build-up) cannot be obtained sufficiently. The upper limit of ΔD50 / Dmod is not particularly limited, but is preferably 2.5 or less, more preferably 2.0 or less. If it exceeds 2.5, the wear resistance is deteriorated and the desired effect may not be obtained.

In this specification, Dmod and ΔD50 of carbon black are values measured by the following method.
A carbon black sample precisely weighed in a 20% aqueous ethanol solution to which a surfactant (“NONIDET P-40” manufactured by SIGMA CHEMICAL) is added is added to prepare a sample solution having a carbon black concentration of 0.01% by weight. A carbon black slurry is prepared by dispersing the sample solution for 5 minutes using an ultrasonic disperser (“Ultrasonic Generator USV-500V” manufactured by Ultrasonic Industry Co., Ltd.) with a vibration frequency of 200 kHz and an output of 100 W. On the other hand, 10 ml of spin solution (pure water) was injected into a centrifugal sedimentation type particle size distribution measuring device (“BI-DCP PARTIC LSIZ” manufactured by BROOK HAVEN INSTRUMENTS), and 1 ml of buffer solution (20 vol% ethanol aqueous solution) was further injected. Thereafter, 1 ml of each of the prepared carbon black slurries is injected, and the Stokes equivalent diameter is measured by centrifugal sedimentation at a rotational speed of 8000 rpm, and a histogram of the occurrence frequency relative to the Stokes equivalent diameter is prepared. Let C be the intersection of a straight line passing through the peak (A) of the histogram and parallel to the Y axis and the X axis of the histogram. The Stokes diameter at C is the maximum frequency Stokes equivalent diameter (Dmod). Further, an intermediate point (D, E) between a straight line G passing through F and parallel to the X axis and a histogram distribution curve (D, E) is obtained with the midpoint of the line segment AC as F, and the difference between the D and E Stokes diameters The absolute value is defined as the Stokes equivalent diameter half-width value (half-value width of distribution curve (ΔD50)).

The carbon black (1) has a cetyltrimethylammonium bromide adsorption specific surface area (CTAB) of preferably 60 to 150 m ² / g, more preferably 80 to 145 m ² / g, still more preferably 100 to 140 m ² / g, and particularly preferably. Is 105 to 135 m ² / g. The effect of this invention is acquired more suitably as CTAB is in the said range.
In the present specification, the cetyltrimethylammonium bromide adsorption specific surface area (CTAB) of carbon black is a value measured in accordance with JIS K6217-3: 2001.

The iodine adsorption amount (IA) (mg / g) of carbon black (1) is preferably 100 to 400 mg / g, more preferably 110 to 300 mg / g, and still more preferably 120 to 250 mg / g. When the iodine adsorption amount (IA) is within the above range, the effect of improving the wear resistance is more suitably obtained, and the effect of the present invention is more suitably obtained.

The ratio (CTAB / IA) of the cetyltrimethylammonium bromide adsorption specific surface area (CTAB) to the iodine adsorption amount (IA) (mg / g) of the carbon black (1) is preferably 0.8 to 1.2 m ² / mg. More preferably, it is 0.85-1.15 m < ² > / mg, More preferably, it is 0.9-1.1 m < ² > / mg. When CTAB / IA is within the above range, the effect of the present invention can be more suitably obtained.
In the present specification, the iodine adsorption amount (IA) of carbon black is a value measured according to JIS K6217-1: 2008.

The surface activity index represented by CTAB / IA can be considered as an index of the crystallinity (graphitization rate) of carbon black. That is, as CTAB / IA is higher, crystallization is less advanced, and the interaction between carbon black and the rubber component tends to increase.
CTAB / IA is also positioned as a parameter for evaluating the amount of acidic functional groups present on the carbon black surface. The acidic functional group on the surface of carbon black contributes to the interaction with the rubber component, but the higher the CTAB / IA, the more acidic functional groups are present on the surface of the carbon black. Therefore, when CTAB / IA is within the above range, a more remarkable reinforcing effect can be exerted on the rubber component, and the effect of the present invention can be obtained more suitably.

24M4 dibutyl phthalate oil absorption of carbon black (1) (24M4DBP) is preferably 50~120cm ³ / 100g, more preferably 70~120cm ³ / 100g, more preferably 90~115cm ³ / 100g, particularly preferably 95 to 110cm is a ³ / 100g. When 24M4DBP is within the above range, the effect of the present invention can be more suitably obtained.
In the present specification, the 24M4 dibutyl phthalate oil absorption (24M4DBP) of carbon black is a value measured according to ASTM D3493-85a.

Carbon black (1) may be acidic, neutral or basic, but preferably has a pH of 2.0 to 10.0 as measured according to JIS K6220-1. More preferably, it is 9.5. When the pH of the carbon black (1) is within the above range, the mechanical strength and wear resistance of the rubber composition can be improved more suitably, and the effects of the present invention can be obtained more suitably.

As a method for producing carbon black (1), for example, a method characterized in that a raw material oil having a BMCI value of 150 or less and an aliphatic hydrocarbon ratio of 30% by mass or more is used as a raw material oil (raw material hydrocarbon). Is preferably adopted. Thereby, carbon black (1) which has the said characteristic is obtained suitably. Further, according to this method, carbon black is prepared in one pot, that is, using the above-mentioned raw material oil, without mixing a plurality of prepared carbon blacks or performing post-treatment such as surface treatment on the prepared carbon black. The carbon black (1) having the above characteristics can be easily prepared simply by preparing the above.

Here, in this specification, the BMCI value is a value calculated from the average boiling point T (° C.) and specific gravity D (60/60 ° F.) when compared with water at 60 ° F. is there.
The average boiling point T is the temperature at which 50% of the raw material oil is distilled off on a mass basis.
BMCI = 48640 / (T + 273) + 473.7D-456.8

In the first aspect of the present invention, the BMCI value of the feedstock is 150 or less, preferably 140 or less, more preferably 130 or less, still more preferably 120 or less, and particularly preferably 110 or less. If it exceeds 150, the particle size distribution of the carbon black becomes too sharp, the above-mentioned specific aggregate characteristics cannot be obtained, and the low heat build-up is deteriorated. The lower limit of the BMCI value of the feedstock oil is not particularly limited, but is preferably 75 or more, more preferably 95 or more. If it is less than 75, the yield may be deteriorated (a sufficient amount of carbon black cannot be obtained).

In the first aspect of the present invention, the aliphatic hydrocarbon ratio (the content of aliphatic hydrocarbons in 100% by mass of the feed oil) is 30% by mass or more, and preferably 40% by mass or more. If it is less than 30% by mass, the above-mentioned specific aggregate characteristics cannot be obtained, and the low heat build-up property is deteriorated. The upper limit of the aliphatic hydrocarbon ratio is not particularly limited, but is preferably 60% by mass or less. If it exceeds 60% by mass, the yield may be deteriorated (a sufficient amount of carbon black cannot be obtained).

The content of aliphatic hydrocarbons derived from animal and vegetable oils or modified products thereof in 100% by mass of aliphatic hydrocarbons contained in the feedstock oil is preferably 10% by mass or more, more preferably 20% by mass or more, and still more preferably. 30% by mass or more. The upper limit of this content is not specifically limited, 100 mass% may be sufficient. When the content is within the above range, not only the effect of the present invention can be obtained more suitably, but also the above effect can be achieved using a non-depleted resource as a raw material, so that resource depletion and the environment can be considered.

As the feedstock satisfying the above characteristics, one satisfying the above characteristics may be used alone, or a mixture of two or more kinds so as to satisfy the above characteristics may be used.

Specific examples of raw material oils include: (1) aromatic hydrocarbons such as anthracene; coal-based hydrocarbons such as creosote oil; EHE oil (replicated oil during ethylene production), FCC oil (fluid catalytic cracking residue oil) And a raw material mixture of at least one selected from the group consisting of petroleum heavy oils such as ()) and (2) aliphatic hydrocarbons. These may be modified. Among these, a mixed raw material oil of coal-based hydrocarbon and aliphatic hydrocarbon is preferable.

As the aliphatic hydrocarbon, for example, petroleum-based aliphatic hydrocarbons typified by process oil, and animal and vegetable oils typified by fatty acids such as soybean oil, rapeseed oil, and palm oil can be used.
Here, animal and vegetable oils include fish oil (liver oil) obtained from fish liver, marine animal oil such as sea animal oil obtained from whales, and land animal oil such as beef tallow and pork fat, as well as plant seeds, fruits, and nuclei. It contains fats and oils and the like containing fatty acid glycerides collected from the above.

Among these, as the raw material oil, a mixed raw material oil of coal-based hydrocarbon and petroleum-based aliphatic hydrocarbon, a mixed raw material oil of coal-based hydrocarbon and animal and vegetable oil is preferable, creosote oil and petroleum-based aliphatic hydrocarbon And mixed raw material oil of creosote oil and soybean oil are more preferable. In addition, tall oil containing aliphatic hydrocarbons can also be suitably used as a raw material oil. In addition, as said coal-type hydrocarbon, coal-type aromatic hydrocarbon is preferable.

Carbon black (1) can be produced by a known production method except that the above-mentioned raw material oil is used, and its production method is not particularly limited. Specifically, carbon black (1) is carbonized by spraying raw material oil into combustion gas. A method for producing black is preferably employed, and conventionally known methods such as a furnace method and a channel method are used. Among these, the furnace method shown below is preferable because the above-mentioned specific aggregate characteristics can be suitably obtained.

The furnace method (oil furnace method) is, for example, as disclosed in Japanese Patent Application Laid-Open No. 2004-43598 and Japanese Patent Application Laid-Open No. 2004-277443. A process using a device having a reaction zone for introducing hydrocarbons and converting raw material hydrocarbons to carbon black by a pyrolysis reaction, and a reaction stop zone for quenching reaction gas to stop the reaction, combustion conditions, high temperature Carbon blacks having various characteristics can be produced by controlling various conditions such as the combustion gas flow rate, the conditions for introducing the raw material oil into the reaction furnace, and the time from the conversion of carbon black to the termination of the reaction.

In the combustion zone, air, oxygen or a mixture thereof and a gaseous or liquid fuel hydrocarbon are mixed and burned as an oxygen-containing gas to form a high-temperature combustion gas. As the fuel hydrocarbon, petroleum-based liquid fuel such as carbon monoxide, natural gas, coal gas, petroleum gas, heavy oil, and coal-based liquid fuel such as creosote oil are used. The combustion is preferably controlled so that the combustion temperature is in the range of 1400 ° C to 2000 ° C.

In the reaction zone, the raw material hydrocarbon is sprayed and introduced into the high-temperature combustion gas flow obtained in the combustion zone in a co-current flow or in a lateral direction, and the raw material hydrocarbon is thermally decomposed and converted to carbon black. Preferably, the feedstock oil is introduced by one or more burners into a high temperature combustion gas stream having a gas flow rate in the range of 100 to 1000 m / s. The feedstock oil is preferably divided and introduced by two or more burners. In order to improve the reaction efficiency, it is preferable to provide a throttle part in the reaction zone. The ratio of the diameter of the throttle part / the diameter of the upstream area of the throttle part is preferably 0.1 to 0.8.

In the reaction stop zone, water spray or the like is performed to cool the high temperature reaction gas to 1000 to 800 ° C. or less. The time from the introduction of the feedstock to the reaction stop is preferably 2 to 100 milliseconds. The cooled carbon black can be separated and recovered from the gas and then subjected to a known process such as granulation and drying.

The amount of carbon black (1) is preferably 1 part by mass or more, more preferably 5 parts by mass or more, still more preferably 10 parts by mass or more, particularly preferably 20 parts by mass or more, relative to 100 parts by mass of the rubber component. Most preferably, it is 35 parts by mass or more. If it is less than 1 part by mass, the effects of the present invention tend not to be sufficiently obtained. The amount of the carbon black is preferably 250 parts by mass or less, more preferably 200 parts by mass or less, still more preferably 150 parts by mass or less, particularly preferably 100 parts by mass or less, with respect to 100 parts by mass of the rubber component. Preferably it is 60 mass parts or less, More preferably, it is 50 mass parts or less. When the amount exceeds 250 parts by mass, the rubber composition becomes too hard, and on the contrary, the wear resistance is lowered, and the processability of the rubber composition tends to be extremely lowered. Also, low exothermicity tends to deteriorate.

In the present invention, carbon black other than carbon black (1) (hereinafter also referred to as carbon black (2)) may be blended with carbon black (1).

Carbon black (2) is not particularly limited, and examples thereof include GPF, FEF, HAF, ISAF, and SAF.

When the rubber composition of the present invention is used for a tread rubber composition, the carbon black (2) has a nitrogen adsorption specific surface area (N ₂ SA) of preferably 80 m ² / g or more, more preferably 90 m ² / g or more, More preferably, it is 100 m ² / g or more. If it is less than 80 m < ² > / g, there exists a tendency for reinforcement property to fall and sufficient abrasion resistance not to be obtained. Also, _N 2 SA of the carbon black (2) is preferably 200 meters ² / g or less, more preferably 190 m ² / g or less, still more preferably not more than 180 m ² / g. If it exceeds 200 m ² / g, the low heat build-up tends to deteriorate. In addition, the dispersibility is inferior, and the fracture performance and wear resistance tend to decrease.
In this specification, _N 2 SA of carbon black, JIS K 6217-2: determined by 2001.

When the rubber composition of the present invention is used for a tread rubber composition, the carbon black (2) has a dibutyl phthalate oil absorption (DBP) of preferably 40 ml / 100 g or more, more preferably 60 ml / 100 g or more. If it is less than 40 ml / 100 g, the reinforcing property is lowered, and there is a tendency that sufficient abrasion resistance cannot be obtained. Further, the DBP of carbon black (2) is preferably 300 ml / 100 g or less, more preferably 200 ml / 100 g or less, still more preferably 100 ml / 100 g or less. If it exceeds 300 ml / 100 g, the durability and elongation at break may be deteriorated.
In the present specification, the DBP of carbon black is measured according to JIS K6217-4: 2001.

When the rubber composition of the present invention is used for a rubber composition for sidewalls, carcass, and clinch, the nitrogen adsorption specific surface area (N ₂ SA) of carbon black (2) is preferably 20 m ² / g or more, more preferably 30 m. ² / g or more. If it is less than 20 m < ² > / g, reinforcement property will fall and there exists a tendency for sufficient durability not to be acquired. Further, N ₂ SA of the carbon black (2) is preferably 110 m ² / g or less, more preferably 100 m ² / g or less. When it exceeds 110 m < ² > / g, there exists a tendency for low exothermic property to deteriorate.

When the rubber composition of the present invention is used for a rubber composition for sidewalls, carcass, and clinch, the carbon black (2) has a dibutyl phthalate oil absorption (DBP) of preferably 40 ml / 100 g or more, more preferably 60 ml / 100 g or more. It is. If it is less than 40 ml / 100 g, the reinforcing property is lowered and sufficient durability tends not to be obtained. The DBP of carbon black (2) is preferably 300 ml / 100 g or less, more preferably 200 ml / 100 g or less, and still more preferably 100 ml / 100 g or less. If it exceeds 300 ml / 100 g, the durability and fatigue resistance may be deteriorated.

The total content of carbon black is preferably at least 1 part by mass, more preferably at least 5 parts by mass, even more preferably at least 10 parts by mass, particularly preferably at least 20 parts by mass, most preferably with respect to 100 parts by mass of the rubber component. Is 35 parts by mass or more. If the amount is less than 1 part by mass, sufficient reinforcement may not be obtained. The total content of the carbon black is preferably 250 parts by mass or less, more preferably 200 parts by mass or less, still more preferably 150 parts by mass or less, particularly preferably 100 parts by mass or less, with respect to 100 parts by mass of the rubber component. Most preferably, it is 60 parts by mass or less, and most preferably 50 parts by mass or less. When it exceeds 250 parts by mass, the workability is lowered, and there is a possibility that low heat build-up, wear resistance, and durability are lowered.

The content of carbon black (1) in 100% by mass of carbon black is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and particularly preferably 20% by mass or more. If it is less than 1% by mass, sufficient effects of the present invention cannot be obtained, and it may be difficult to achieve both wear resistance and low heat build-up. The content may be 100% by mass, but is preferably 80% by mass or less when used with other carbon black.

In the present invention, silica may be blended in addition to the amphoteric compound having carbon black (1), a specific acidic functional group and a specific basic functional group. Thereby, abrasion resistance and low heat generation property can be improved more remarkably.

The silica is not particularly limited, and examples thereof include dry method silica (anhydrous silica), wet method silica (hydrous silica) and the like, and wet method silica is preferable because of its large number of silanol groups.

The nitrogen adsorption specific surface area (N ₂ SA) of silica is preferably 45 m ² / g or more, more preferably 55 m ² / g or more, still more preferably 60 m ² / g or more, particularly preferably 100 m ² / g or more, and most preferably. Is 150 m ² / g or more. If it is less than 45 m ² / g, the wear resistance and rubber breaking strength may be deteriorated. Further, N ₂ SA of silica is preferably 350 m ² / g or less, more preferably 300 m ² / g or less, still more preferably 270 m ² / g or less, and particularly preferably 220 m ² / g or less. If it exceeds 350 m ² / g, it is difficult to disperse silica, and the low heat build-up may be deteriorated.
The nitrogen adsorption specific surface area of silica is a value measured by the BET method according to ASTM D3037-81.

When the rubber composition of the present invention contains silica, the content of silica is preferably 1 part by mass or more, more preferably 10 parts by mass or more, still more preferably 30 parts by mass or more, with respect to 100 parts by mass of the rubber component. Particularly preferred is 45 parts by mass or more. If the amount is less than 1 part by mass, the effect of blending silica cannot be sufficiently obtained, and the low heat buildup and wear resistance tend to deteriorate. The silica content is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, still more preferably 120 parts by mass or less, particularly preferably 100 parts by mass or less, and most preferably 70 parts by mass or less. If the amount exceeds 200 parts by mass, silica is difficult to disperse, so that workability, low heat build-up, and wear resistance tend to deteriorate.

In the rubber composition of the present invention, when silica is blended, it is preferable to use a silane coupling agent together.

As the silane coupling agent, any silane coupling agent conventionally used in combination with silica can be used in the rubber industry, and examples thereof include sulfide systems such as bis (3-triethoxysilylpropyl) disulfide, 3- Mercapto type such as mercaptopropyltrimethoxysilane, vinyl type such as vinyltriethoxysilane, amino type such as 3-aminopropyltriethoxysilane, glycidoxy type of γ-glycidoxypropyltriethoxysilane, 3-nitropropyltrimethoxy Examples thereof include nitro compounds such as silane and chloro compounds such as 3-chloropropyltrimethoxysilane. Among these, sulfide type is preferable, and bis (3-triethoxysilylpropyl) tetrasulfide is more preferable.

When the rubber composition of the present invention contains a silane coupling agent, the content of the silane coupling agent is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more with respect to 100 parts by mass of silica. It is. If it is less than 0.1 parts by mass, the wear resistance and low heat build-up tend to be greatly reduced. Further, the content of the silane coupling agent is preferably 15 parts by mass or less, more preferably 10 parts by mass or less. When it exceeds 15 parts by mass, an excess silane coupling agent remains, which may cause deterioration in processability and wear resistance of the resulting rubber composition.

The rubber composition of the present invention comprises a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group. And at least one amphoteric compound having an acidic functional group that is at least one functional group selected from the group consisting of: and a basic functional group that is an amino group or a substituted amino group. In such amphoteric compounds, the basic functional group moiety reacts with a functional group such as a carboxyl group present on the surface of the carbon black to bind to carbon black, and the acidic functional group moiety forms a double bond of rubber (polymer). react. Therefore, the dispersibility of carbon black is improved and the dispersion state can be maintained. Moreover, since carbon black is restrained by reaction, it becomes possible to suppress exothermic property. Therefore, the aforementioned performance can be improved in a well-balanced manner. Also, good workability can be obtained. In the present invention, in order to use the specific carbon black and the amphoteric compound in combination, the reactivity between the basic functional group of the amphoteric compound and the acidic functional group on the surface of the specific carbon black is high. Thereby, it is possible to synergistically improve both wear resistance and low heat buildup while maintaining good processability.

Examples of the acidic functional group in the amphoteric compound include a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group (—SSO ₃ H), a dithiocarboxylic acid group (—CSSH), and an alkyl group having 1 to 20 carbon atoms. Examples thereof include a thioalkyl carboxylic acid group (—SRCOOH: R is a linear or branched alkyl group), a phenolic hydroxyl group, etc. Among them, a carboxylic acid group and a thiosulfonic acid group are preferable. In addition to the carboxyl group, the carboxylic acid group includes a carboxylic acid ester group, a carboxylic acid group, and an amide group.
Examples of the basic functional group include amino groups such as primary amino groups, secondary amino groups, and tertiary amino groups, substituted amino groups, and the like.
The amphoteric compound may be a metal salt of the compound.

The content of the amphoteric compound is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, still more preferably 0.2 parts by mass or more, particularly preferably 0 with respect to 100 parts by mass of carbon black. .5 parts by mass or more. If it is less than 0.01 parts by mass, the low heat build-up and mechanical strength (particularly low heat build-up) may not be improved in a well-balanced manner. In addition, the content of the amphoteric compound is 30 parts by mass or less, more preferably 10 parts by mass or less, still more preferably 9 parts by mass or less, and particularly preferably 6 parts by mass or less with respect to 100 parts by mass of carbon black. If it exceeds 30 parts by mass, the mechanical strength, wear resistance, and vulcanization stability may be deteriorated.

The amphoteric compound is preferably a compound represented by the following formula (I) (also referred to as “compound (I)” in the present specification).

In the above formula (I), ^{R 1} represents an alkylene group, an alkenylene group or an alkynylene group having 2 to 30 carbon atoms. A is selected from the group consisting of a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group. Represents an acidic functional group that is at least one functional group. R ² and R ³ are the same or different and are a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, or an alkyl group having 1 to 20 carbon atoms. Represents an alkoxysilyl group. The compound represented by the above formula (I) may be a metal salt of the compound.

<Compound (I)>
The compound (I) is represented by the above formula (I). In the above formula (I), the alkylene group, alkenylene group and alkynylene group of R ¹ preferably have 2 to 18 carbon atoms, more preferably 2 to 2 carbon atoms. 12. The R ¹ may be linear or branched. Specific examples of the alkylene group include ethylene, propylene, and butylene groups. Specific examples of the alkenylene group include vinylene, propenylene, and butenylene. Specific examples of the alkynylene group include an ethynylene group, a propynylene group, and a butynylene group. Examples of the acidic functional group for A include those described above. Examples of the alkyl group having 1 to 20 carbon atoms of R ² and R ³ include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkenyl group include a vinyl group, a propenyl group, and a butenyl group. An ethynyl group, a propynyl group, a butynyl group, etc. are mentioned, As a C1-C20 alkoxysilyl group, a triethoxysilyl group, a trimethoxysilyl group, etc. are mentioned.

The compound (I) is preferably a compound represented by the following formula (I-1) and / or the following formula (I-2).

In said formula (I-1), p represents the integer of 2-8. In said formula (I-2), q represents the integer of 2-8. M ^{r +} represents a metal ion, and r represents its valence.

The compound represented by the above formula (I-2) can be produced by any known method. Specifically, a method of reacting a haloalkylamine with sodium thiosulfate, reacting a potassium salt of phthalimide with a dihaloalkane, reacting the resulting compound with sodium thiosulfate, and then reacting the resulting compound with The method of hydrolyzing is mentioned.

Specifically, when q is a compound of 6, for example, a method of reacting 6-halohexylamine with sodium thiosulfate, a compound obtained by reacting a potassium salt of phthalimide with 1,6-dihalohexane And a method in which sodium thiosulfate is reacted and then the resulting compound is hydrolyzed.

When q is a compound of 3, for example, a method in which 3-halopropylamine and sodium thiosulfate are reacted, a potassium salt of phthalimide and 1,3-dihalopropane are reacted, Examples include a method of reacting with sodium thiosulfate and then hydrolyzing the obtained compound.

The compound represented by the above formula (I-1) can be produced, for example, by reacting the compound represented by the above formula (I-2) with a protonic acid.

In the present invention, a mixture of the compound represented by the above formula (I-1) and the compound represented by the above formula (I-2) can also be used. Such a mixture is prepared by mixing a compound represented by the above formula (I-1) with a compound represented by the above formula (I-2), a metal alkali (a hydroxide containing a metal represented by the above M). , Carbonates and bicarbonates, etc.), a method of metallizing a part of the compound represented by the above formula (I-1), a compound represented by the above formula (I-2) using a protonic acid It can manufacture by the method of neutralizing a part of. The compound represented by the above formula (I-1) and the compound represented by the above formula (I-2) thus produced can be taken out from the reaction mixture by operations such as concentration and crystallization. The extracted compound represented by the formula (I-1) and the compound represented by the formula (I-2) usually contain about 0.1 to 5% of water. In the present invention, only the compound represented by the above formula (I-1) can be used, or only the compound represented by the above formula (I-2) can be used. Moreover, the compound represented by the multiple types of compound represented by the said formula (I-1), and the said formula (I-2) can also be used together.

In said formula (I-1), p represents the integer of 2-8 and 2-6 are preferable. In said formula (I-2), q represents the integer of 2-8 and 2-6 are preferable.

The metal ion represented by ^{Mr +} is preferably lithium ion, sodium ion, potassium ion, cesium ion, cobalt ion, copper ion, or zinc ion, more preferably lithium ion, sodium ion, or potassium ion, and sodium ion. Further preferred. r represents the valence of the metal ion, and is not limited as long as it is a possible range for the metal. When the metal ion is an alkali metal ion such as lithium ion, sodium ion, potassium ion or cesium ion, r is usually 1, and when the metal ion is cobalt ion, r is usually 2 or 3. When the metal ion is a copper ion, r is usually an integer of 1 to 3, and when the metal ion is a zinc ion, r is usually 2. According to the said manufacturing method, although the sodium salt of the compound represented by the said formula (I-1) is obtained normally, it can convert into metal salts other than a sodium salt by performing a cation exchange reaction.

The median diameter of the compound represented by the formula (I-1) and the compound represented by the formula (I-2) is preferably in the range of 0.05 to 100 μm, more preferably in the range of 1 to 100 μm. It is. Such median diameter can be measured by a laser diffraction method.

The compound represented by the above formula (I-1) and the compound represented by the above formula (I-2) may be used after being previously mixed with a carrier. Examples of the support agent include “inorganic fillers and reinforcing agents” described on pages 510 to 513 of “Rubber Industry Handbook <Fourth Edition>” edited by the Japan Rubber Association. Among them, carbon black, silica, calcined, etc. Clay and aluminum hydroxide are preferred. Although the usage-amount of a support agent is not specifically limited, It is 10-1000 mass parts with respect to 100 mass parts of total amounts of the compound represented by the said Formula (I-1) and / or the said Formula (I-2). A range is preferred.

It is also one of preferred embodiments of the present invention that the amphoteric compound is at least one selected from the group consisting of (A1), (B1), (C1) and (D1).
(A1): Compound represented by the following formula (II) (also referred to as “compound (II)” in this specification)
(B1): salt of compound (II) (C1): solvate of compound (II) (D1): solvate of salt of compound (II)

In the above formula (II), R ¹¹ is an optionally substituted alkanediyl group having 2 to 12 carbon atoms, an optionally substituted cycloalkanediyl group having 3 to 12 carbon atoms, or * —B ¹ —Ar—B ² — * group, and * represents a bond. B ¹ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms. B ² represents a single bond or an alkanediyl group having 1 to 12 carbon atoms. Ar represents a C6-C12 divalent aromatic hydrocarbon group which may have a substituent. R ¹² and R ¹³ are the same or different and each represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxy group, or an alkoxy group having 1 to 6 carbon atoms. Alternatively, they are bonded to each other to form an alkanediyl group having 2 to 12 carbon atoms. R ¹⁴ represents a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylalkoxy group having 7 to 15 carbon atoms, or —NR ¹⁵ R ¹⁶ , wherein R ¹⁵ and R ¹⁶ are These are the same or different and each represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms. X represents -NH- or -O-.

<Compound (II)>
The salt of compound (II) is a carboxylate salt of compound (II) wherein R ¹⁴ is a hydroxy group, and an addition formed with an acid at the amine moiety (—NH ₂ or —NH—) in compound (II) Contains salt.
As a carboxylate salt of compound (II), for example, R ¹⁴ in formula (II) represents —O ⁻ (Y ^{n +} ) ^{1 / n} (Y ^{n +} represents an n-valent cation, and n represents 1 or 2). .), That is, a salt represented by the following formula (IV).

In said formula (IV), R < ¹¹ >, R <^12> , R <^13> and X represent the same meaning as the above. Y ^{n +} represents an n-valent metal cation, NH ₄ ⁺ , or an n-valent organic cation, and n represents 1 or 2.

Examples of the acid in the addition salt formed with the acid in the amine moiety in compound (II) include inorganic acids and organic acids.
Examples of solvates include methanol solvates and hydrates.
Regarding the bond between the carbon-carbon double bond in compound (II) and R ¹³ and CO—R ¹⁴ , the carbon-carbon double bond has an E-form compound, a Z-form compound, or an E-form compound. Either a compound or a mixture of Z-form compounds may be used. Among them, a compound in which the carbon-carbon double bond steric is a Z-form is preferable.
Moreover, as compound (II), the compound represented by following formula (III) is preferable.

In said formula (III), R < ¹¹ >, R < ¹² >, R <^13> , R <^14> and X represent the same meaning as the above.

Examples of the alkanediyl group having 2 to 12 carbon atoms in R ¹¹ include linear alkanediyl groups such as ethylene group, trimethylene group, tetramethylene group, pentamethylene group and hexamethylene group; isopropylene group and isobutylene group , Branched alkanediyl groups such as 2-methyltrimethylene group, isopentylene group, isohexylene group, isooctylene group, 2-ethylhexylene group, and isodecylene group. Especially, 3-12 are preferable and, as for carbon number of an alkanediyl group, 3-6 are more preferable. Moreover, a linear alkanediyl group is preferable.

Examples of the substituent that the alkanediyl group may have include, for example, an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group, and a butoxy group, a halogen atom such as chlorine, bromine, iodine, and fluorine, and a phenyl group. And aryl groups having 6 to 12 carbon atoms such as naphthyl group and biphenyl group, and hydroxy groups. Examples of the alkanediyl group having a substituent include the following groups. * Represents a bond.

Examples of the cycloalkanediyl group having 3 to 12 carbon atoms in R ¹¹ include a cyclopropylene group, a cyclopentylene group, a cyclohexylene group, a cyclododecylene group, and the like.
Examples of the substituent that the C3-C12 cycloalkanediyl group may have include, for example, a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a t-butyl group, etc. An alkyl group having 4 carbon atoms; an aryl group having 6 to 10 carbon atoms such as a phenyl group, a 4-methylphenyl group and a naphthyl group; an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group and an n-butoxy group; an acetyl group An acyl group having 1 to 7 carbon atoms such as benzoyl group, formyl group and pivaloyl group; an alkoxycarbonyl group having 3 to 4 carbon atoms such as methoxycarbonyl group and ethoxycarbonyl group; carbon such as phenoxycarbonyl group and naphthyloxycarbonyl group And an aryloxycarbonyl group having 7 to 11 carbon atoms; an acyloxy group having 2 to 7 carbon atoms such as an acetoxy group and a benzoyloxy group;
The cycloalkanediyl group having 3 to 12 carbon atoms is preferably a cyclopentylene group, a cyclohexylene group, a methylcyclohexylene group or a t-butylcyclohexylene group.

Examples of the alkanediyl group having 1 to 12 carbon atoms in B ¹ and B ² include the same ones as described above and a methylene group.
Examples of the divalent aromatic hydrocarbon group having 6 to 12 carbon atoms in Ar include a phenylene group, a naphthylene group, and a biphenylene group.
Examples of the * —B ¹ —Ar—B ² — * group in R ¹¹ include a phenylene group, a naphthylene group, a biphenylene group, and the following groups. * Represents a bond.

The hydrogen atom contained in Ar is one or more selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a hydroxy group, a nitro group, a cyano group, a sulfo group, and a halogen atom. It may be substituted with a group.

The R ^11, alkanediyl group or ^* -B 1 ^{-Ar-B 2} having 2 to 12 carbon atoms - preferably * group, which may have an alkanediyl group or a substituent having 2 to 12 carbon atoms atoms A divalent aromatic hydrocarbon group having 6 to 12 carbon atoms is more preferable, a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent is further preferable, and a phenylene group is particularly preferable.

Examples of the halogen atom for R ¹² and R ¹³ include fluorine, chlorine, bromine and iodine.
Examples of the alkyl group having 1 to 6 carbon atoms in R ¹² and R ¹³ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. , N-pentyl group, isopentyl group, n-hexyl group and the like.
The aryl group having 6 to 12 carbon atoms in R ¹² and R ¹³ represents a monocyclic or condensed polycyclic aromatic hydrocarbon having 6 to 12 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and a biphenyl group. It is done.
Examples of the alkoxy group having 1 to 6 carbon atoms in R ¹² and R ¹³ include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an isobutoxy group, a sec-butoxy group, and a tert-butoxy group. Group, n-pentoxy group, isopentoxy group, n-hexyloxy group and the like.
When R ¹² and R ¹³ are bonded to each other to form an alkanediyl group having 2 to 12 carbon atoms, examples of the alkanediyl group include the same groups as described above, and are alkanediyl groups having 3 or 4 carbon atoms. It is preferable. Examples of the cyclic structure formed by R ¹² and R ¹³ together with the carbon atom to which R ¹² and R ¹³ are bonded include a cyclopentene ring and a cyclohexene ring.
R ¹² is hydrogen ^atom, it is preferred that ^{R 13} is an alkyl group having 1 to 6 carbon hydrogen or ^C, and more preferably ^{R 12} and ^{R 13} are hydrogen atoms.

Examples of the alkoxy group having 1 to 6 carbon atoms for R ¹⁴ include the same groups as described above.
Examples of the aryloxy group having 6 to 12 carbon atoms in R ¹⁴ include groups in which an oxy group is bonded to the above aryl group having 6 to 12 carbon atoms, such as a phenyloxy group, a naphthyloxy group, and a biphenyloxy group. Is mentioned.
Examples of the arylalkoxy group having 7 to 15 carbon atoms for R ¹⁴ include a phenylethyloxy group, a benzyloxy group, and phenylpropyloxy.
Examples of —NR ¹⁵ R ¹⁶ in R ¹⁴ include a methylamino group, an ethylamino group, a phenylamino group, an ethylmethylamino group, a dimethylamino group, a diethylamino group, a methylphenylamino group, an ethylphenylamino group, and a diphenylamino group. Can be mentioned.
R ¹⁴ is preferably a hydroxy group.
X is preferably -NH-.

In the case where the carboxylate salt of the compound (II) is a salt represented by the formula (IV), Y ^{n +} is a group consisting of an alkali metal, an alkaline earth metal, and a transition element of groups IB and IIB of the periodic table Cations of metals selected from: Cations of organic bases that can form salts with carboxy groups such as amines, etc., for example, Li ⁺ , Na ⁺ , K ⁺ , Mg ²⁺ , Ca ²⁺ , Ba ²⁺ , Zn ²⁺ , Cu _{^{2+, Cu +, Ag +,}} (NH 4) +, [NH (C 2 H 5) 3] +, [NH (C 2 H 5) (i-C 3 H 7) 2] +, + H 3 N ^{_{- (CH 2) 2 -NH 3}} +, + H 3 N- (CH 2) 6 -NH 3 + , and the like. Of these, alkali metal cations are preferred.

Specific examples of compound (II) are shown below.

<Method for Producing Compound (II)>
Compound (II) can be produced, for example, by performing a reaction represented by the following formula (a), (b), or (c).

In the above formulas (a), (b) and (c), R ¹¹ , R ¹² , R ¹³ and R ¹⁴ represent the same meaning as described above. P ¹ represents a protecting group.

Examples of the protecting group for P ¹ include a tert-butoxycarbonyl group. When a protecting group is used, the protecting group can be removed by a commonly used method. In particular, the compound represented by the formula (III) can be produced by subjecting a corresponding acid anhydride such as maleic anhydride to an esterification reaction, an amidation reaction or a salt formation reaction.

<Method for Producing Compound (II) Salt>
The salt of compound (II) is produced, for example, by the reaction represented by the above formula (a), (b), or (c) to produce compound (II) in which R ¹⁴ is a hydroxy group. Can be produced by carrying out a salt-forming reaction. Examples of the salt forming reaction include a reaction in which the compound (II) is metallated using a metal.

<Method for Producing Salt Represented by Formula (IV)>
The salt represented by the above formula (IV) can be produced, for example, by the method represented by the following formula.

In said formula, R < ¹¹ >, R <^12> , R < ¹³ > and Y represent the same meaning as the above. P ¹ represents a protecting group.

Examples of the protecting group for P ¹ include a tert-butoxycarbonyl group. When a protecting group is used, the protecting group can be removed by a commonly used method.
For example, the salt represented by the formula (IV) can produce a compound (II) in which R ¹⁴ is a hydroxy group by the reaction represented by the formula (a), (b), or (c). About (II), it can manufacture by performing salt formation reaction. As the salt formation reaction, the compound (II) is converted into a metal salt using a metal (a hydroxide, carbonate, bicarbonate, etc. containing a metal represented by the above Y), or a carboxy group such as an amine. And a reaction to form a salt using an organic base capable of forming a salt.

<Method for Producing Compound (II) Hydrate>
The hydrate of compound (II) is obtained by, for example, performing the reaction represented by the above formula (a), (b), or (c) in a mixed solvent of water and an organic solvent, or compound (II) Can be produced by repulping or recrystallization with an aqueous solvent.

<Method for producing methanol solvate of compound (II)>
For the methanol solvate of compound (II), for example, the reaction represented by formula (a), (b), or (c) is carried out in an organic solvent containing methanol, or compound (II) is produced. Then, it can manufacture by performing a repulp or recrystallization with a methanol solvent.

<Method for Producing Compound (II) Salt Hydrate>
A hydrate of a salt of compound (II) is produced by, for example, producing compound (II) in which R ¹⁴ is a hydroxy group by a reaction represented by formula (a), (b), or (c). About (II), it can manufacture by performing a salt formation reaction in the mixed solvent of water and an organic solvent, or manufacturing a salt of compound (II), and then performing repulping or recrystallization with an aqueous solvent. .

<Method for producing methanol solvate of salt of compound (II)>
The methanol solvate of the salt of compound (II) produces compound (II) in which R ¹⁴ is a hydroxy group, for example, by the reaction represented by formula (a), (b), or (c), and the compound About (II), it can manufacture by performing a salt formation reaction in the organic solvent containing methanol, or manufacturing a salt of compound (II), and then performing repulping or recrystallization with a methanol solvent.

In the rubber composition of the present invention, in addition to the above components, compounding agents generally used in the production of rubber compositions, for example, reinforcing fillers such as clay and talc, zinc oxide, stearic acid, processing aids, Various anti-aging agents, softening agents such as oil, vulcanizing agents such as waxes, sulfur and sulfur-containing compounds, vulcanization accelerators and the like can be appropriately blended.

As the oil, for example, process oil, vegetable oil or fat, or a mixture thereof may be used. Examples of the process oil include paraffinic process oil, naphthenic process oil, aromatic process oil (aromatic process oil), and the like. Vegetable oils include castor oil, cottonseed oil, sesame oil, rapeseed oil, soybean oil, palm oil, palm oil, peanut oil, rosin, pine oil, pineapple, tall oil, corn oil, rice bran oil, beet flower oil, sesame oil, Examples include olive oil, sunflower oil, palm kernel oil, cocoon oil, jojoba oil, macadamia nut oil, safflower oil, and tung oil. Of these, aromatic process oils are preferred because they are compatible with rubber and can maintain tan δ.

The oil content is preferably 1 part by mass or more, more preferably 3 parts by mass or more, with respect to 100 parts by mass of the rubber component. If it is less than 1 part by mass, the processability is inferior, and low heat build-up and wear resistance may be reduced. The oil content is preferably 15 parts by mass or less, more preferably 8 parts by mass or less. If it exceeds 15 parts by mass, wet grip performance and wear resistance may be deteriorated.

Examples of the vulcanization accelerator include 2-mercaptobenzothiazole, dibenzothiazyl disulfide, and thiazole vulcanization accelerators such as N-cyclohexyl-2-benzothiazylsulfenamide; tetramethylthiuram monosulfide, tetramethylthiuram disulfide Thiuram vulcanization accelerators such as N-cyclohexyl-2-benzothiazole sulfenamide, Nt-butyl-2-benzothiazole sulfenamide, N-oxyethylene-2-benzothiazole sulfenamide, N- Sulfenamide vulcanization accelerators such as oxyethylene-2-benzothiazole sulfenamide and N, N′-diisopropyl-2-benzothiazole sulfenamide; Guani It can be mentioned emission-based vulcanization accelerator. Of these, sulfenamide-based vulcanization accelerators are preferable and Nt-butyl-2-benzothiazole sulfenamide is more preferable because the effects of the present invention can be more suitably obtained. It is also preferable to use a guanidine vulcanization accelerator in combination. 0.1-7 mass parts is preferable with respect to 100 mass parts of rubber components, and, as for the usage-amount of a vulcanization accelerator, More preferably, it is 0.5-5 mass parts.

Although it does not specifically limit as a vulcanizing agent, Sulfur can be used conveniently. The content of sulfur is preferably 0.5 to 5 parts by mass, more preferably 1 to 3 parts by mass with respect to 100 parts by mass of the rubber component. Thereby, the effect of this invention is acquired more suitably.

The rubber composition of the present invention is produced by a general method. That is, it can be produced by a method of kneading each component with a Banbury mixer, a kneader, an open roll, a closed kneader or the like and then vulcanizing.

The rubber composition of the present invention can be used as a tire rubber composition, and in particular, can be suitably used as a tire rubber composition. The rubber composition of the present invention can be used for each member of a tire, and among them, it can be suitably used for treads (cap treads), base treads, under treads, sidewalls, carcass, clinch and the like.

The pneumatic tire of the present invention is produced by a usual method using the rubber composition.
That is, the rubber composition containing the above components is extruded in accordance with the shape of each tire member such as a tread at an unvulcanized stage, and is molded together with the other tire members by a normal method on a tire molding machine. By doing so, an unvulcanized tire is formed. The unvulcanized tire is heated and pressurized in a vulcanizer to obtain a tire.

The pneumatic tire of the present invention is suitably used as a passenger car tire, truck / bus tire, motorcycle tire, high-performance tire and the like.

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

[Carbon black production equipment]
A raw material introduction zone comprising an inner diameter of 500 mm having an air introduction duct and a combustion burner, a length of 1750 mm, a combustion zone having a length of 1750 mm, an inner diameter of 55 mm having a raw material nozzle penetrating from the periphery, and a narrow diameter portion having a length of 700 mm, A carbon black production facility in which a rear reaction zone having an inner diameter of 200 mm and a length of 2700 mm equipped with a quench device was sequentially joined was used.
[Production conditions] (Furnace method)
Using this production facility, carbon black was produced using natural gas as a fuel, using oils and petroleum hydrocarbons whose characteristics are shown in Table 1 as raw material oils, and other conditions shown in Table 2 as other conditions. Table 2 shows the yield and various characteristics of the carbon black obtained in each production example. Incidentally, various characteristics of carbon black were measured by the above-described methods. Further, the carbon blacks obtained in Production Examples 2-5 and 7-14 correspond to the carbon black (1). Note that the carbon black obtained by Production Example 12-14 had a poor yield, and carbon black that could be evaluated was not obtained. Therefore, the value of the amount of the raw material oil in the production conditions could not be confirmed. The measurement of various characteristics of black and the test for blending carbon black described later into the rubber composition were not performed.

(Production Example A S- (3-aminopropyl) thiosulfuric acid (amphoteric compound A))
To a reaction vessel substituted with nitrogen gas, 75 g of 3-bromopropylamine hydrobromide, 85.26 g of sodium thiosulfate pentahydrate, 375 ml of methanol and 375 ml of water were added, and the mixture was refluxed at 70 ° C. for 5 hours. did. After allowing to cool, methanol was removed under reduced pressure. To the residue was added 13.68 g of sodium hydroxide, and the mixture was stirred at room temperature for 1 hour, and then the solvent was removed under reduced pressure. 600 ml of ethanol was added to the obtained residue and refluxed for 1.5 hours. Hot filtration was performed, and the filtrate was concentrated under reduced pressure to obtain crystals. The crystals were removed by filtration and washed with ethanol. Further, washing with hexane was performed. The obtained crystals were vacuum-dried to obtain sodium S- (3-aminopropyl) thiosulfate. 52 g of sodium S- (3-aminopropyl) thiosulfate, 90 ml of water and 5 mol / l hydrochloric acid were added to the reaction vessel substituted with nitrogen gas, and the resulting solution was concentrated under reduced pressure, and the crystals were taken out by filtration. The obtained crystal was vacuum-dried to obtain S- (3-aminopropyl) thiosulfuric acid represented by the following formula (A).

(Production Example B S- (6-Aminohexyl) thiosulfuric acid (amphoteric compound B))
To the reaction vessel, 99.2 g of potassium phthalimide and 480 ml of dimethylformamide were added. To this mixture, a mixture of 200 g of 1,6-dibromohexane and 200 ml of dimethylformamide was added dropwise at room temperature. After completion of the dropwise addition, the resulting mixture was heated to 120 ° C. and refluxed for 5 hours. After standing to cool, the solvent was distilled off from the reaction mixture. Ethyl acetate and water were added for liquid separation, and then the organic layer was concentrated. Hexane and ethyl acetate were added to the resulting residue to precipitate crystals. The crystals were taken out and dried under vacuum to obtain N- (6-bromohexyl) phthalimide. To the reaction vessel, 40 g of N- (6-bromohexyl) phthalimide, 32.0 g of sodium thiosulfate pentahydrate, 200 ml of methanol and 200 ml of water were added, and the mixture was refluxed for 5 hours, allowed to cool and then the reaction mixture. The solvent was distilled off. To the obtained residue, 200 ml of ethanol was added and refluxed for 1.5 hours. Hot filtration was performed, and the filtrate was concentrated under reduced pressure to obtain crystals, and then allowed to stand. The crystals were taken out by filtration, washed with ethanol, and further washed with hexane. The obtained crystals were vacuum-dried to obtain 6-phthalimidohexyl thiosulfate sodium salt. A reaction vessel purged with nitrogen was charged with 20.0 g (54.7 mmol) of sodium salt of 6-phthalimidohexylthiosulfate and 200 ml of ethanol, and 4.25 g (84.8 mmol) of hydrazine monohydrate was added to the resulting mixture. It was dripped. After completion of the dropwise addition, the resulting mixture was stirred at 70 ° C. for 5 hours, and then ethanol was distilled off under reduced pressure. 100 ml of methanol was added to the residue and refluxed for 1 hour. Crystals were obtained by hot filtration, washed with methanol, and vacuum-dried to obtain S- (6-aminohexyl) thiosulfate sodium salt. 26 g of sodium S- (6-aminohexyl) thiosulfate, 45 ml of water and 5 mol / l hydrochloric acid were added to the reaction vessel substituted with nitrogen gas, the resulting solution was concentrated under reduced pressure, and the crystals were taken out by filtration. The obtained crystal was vacuum-dried to obtain S- (6-aminohexyl) thiosulfuric acid represented by the following formula (B).

The median diameter (50% D) of the amphoteric compounds A and B obtained in the above Production Examples A and B was measured by a laser diffraction method (measurement procedure is as follows) using SALD 2000J type manufactured by Shimadzu Corporation. As a result, the median diameter (50% D) was 66.7 μm. The obtained amphoteric compounds A and B were pulverized and both median diameters (50% D) were adjusted to 14.6 μm and used in the following examples.

<Measurement operation>
The amphoteric compounds A and B obtained in Production Examples A and B were each dispersed at room temperature in a mixed solution of a dispersion solvent (toluene) and a dispersing agent (10% by mass sodium 2-ethylhexyl sulfosuccinate / toluene solution). Then, while irradiating the obtained dispersion with ultrasonic waves, the dispersion was stirred for 5 minutes to obtain a test solution. The test solution was transferred to a batch cell and measured after 1 minute. (Refractive index: 1.70-0.20i)

(Production Example C Sodium (2Z) -4-[(4-aminophenyl) amino] -4-oxo-2-butenoic acid methanolate (amphoteric compound C))
Under a nitrogen atmosphere, 195.5 g (1.81 mol) of 1,4-phenylenediamine and 3000 ml of tetrahydrofuran were charged in a reaction vessel. A solution prepared by dissolving 118.1 g (1.20 mol) of maleic anhydride in 1200 ml of tetrahydrofuran was added dropwise thereto in about 3 hours under ice cooling, and the mixture was stirred overnight at room temperature. After completion of the reaction, the precipitated crystals were collected by filtration, washed twice with 250 ml of tetrahydrofuran, dried at 40 ° C., and crude (2Z) -4-[(4-aminophenyl) amino] -4-oxo-2- 241.8 g of butenoic acid was obtained as a yellow-orange powder. 484 ml of water was added to 241.8 g of crude (2Z) -4-[(4-aminophenyl) amino] -4-oxo-2-butenoic acid, cooled to 0 to 10 ° C., 216 ml of 5N aqueous sodium hydroxide solution, Subsequently, 21 ml of 1N aqueous sodium hydroxide solution was added dropwise. Thereafter, 200 ml of 2-propanol was added to the residue obtained by distilling off the solvent under reduced pressure, and the solvent was again distilled off under reduced pressure. To the obtained tan solid was added 800 ml of tetrahydrofuran and stirred overnight at room temperature. The solid was collected by filtration, washed with 100 ml of tetrahydrofuran three times and dried to obtain crude sodium (2Z) -4-[(4-aminophenyl). ) 279 g of amino] -4-oxo-2-butenoic acid were obtained. Crude sodium (2Z) -4-[(4-aminophenyl) amino] -4-oxo-2-butenoic acid (279 g) was divided into two portions, 2800 ml of methanol was added to each, and the mixture was heated under reflux for 1 hour, and then filtered while hot. Insoluble matter was removed. The solids obtained by concentrating the filtrate under reduced pressure were combined, 750 ml of tetrahydrofuran was added, and the mixture was stirred overnight at room temperature, kept at 50 ° C. for 30 minutes, and then filtered while hot. The obtained solid was washed three times with 150 ml of tetrahydrofuran, dried under reduced pressure at 45 ° C. for 5 hours, and sodium (2Z) -4-[(4-aminophenyl) amino] -4 represented by the following formula (C): 264.6 g of oxo-2-butenoic acid methanolate was obtained as a pale brownish white powder. Yield 84.5%.
H ¹ -NMR (300 MHz, DMSO-d6) δ _ppm : 14.6 (1H, s), 7.3 (2H, d, J = 8.9 Hz), 6.5 (2H, d, J = 8. 9 Hz), 6.1 (1 H, d, J = 13.5 Hz), 5.6 (1 H, d, J = 13.5 Hz), 4.1 (1 H, q, J = 5.4, 10.5 Hz) ), 4.8 (2H, s), 3.2 (3H, s).

Hereinafter, various chemicals used in Examples and Comparative Examples will be described together.
NR: TSR20
BR: Ubepol BR150B manufactured by Ube Industries, Ltd. (cis content: 97% by mass)
Carbon black: carbon black amphoteric compound A obtained in Production Examples 1 to 11: S- (3-aminopropyl) thiosulfuric acid (prepared in Production Example A)
Amphoteric Compound B: S- (6-Aminohexyl) thiosulfuric acid (prepared in Production Example B)
Amphoteric compound C: Sodium (2Z) -4-[(4-aminophenyl) amino] -4-oxo-2-butenoic acid methanolate (prepared in Preparation C)
Oil: Process X-140 (aromatic process oil) manufactured by Japan Energy Co., Ltd.
Zinc oxide: Zinc Hana No. 1 manufactured by Mitsui Mining & Smelting Co., Ltd. Stearic acid: Stearic acid “Kashiwa” manufactured by NOF Corporation
Anti-aging agent: NOCRACK 6C (N- (1,3-dimethylbutyl) -N′-phenyl-p-phenylenediamine) manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.
Sulfur: Powdered sulfur vulcanization accelerator manufactured by Tsurumi Chemical Industry Co., Ltd .: Noxeller NS (N-tert-butyl-2-benzothiazolylsulfenamide) manufactured by Ouchi Shinsei Chemical Industry Co., Ltd.

(Examples and Comparative Examples)
Using a 1.7 L Banbury mixer, materials other than sulfur and a vulcanization accelerator were kneaded for 3 minutes at 160 ° C. in accordance with the blending contents shown in Tables 3 to 6 to obtain a kneaded product. Next, sulfur and a vulcanization accelerator were added to the obtained kneaded product, and kneaded for 5 minutes at 80 ° C. using a biaxial open roll to obtain an unvulcanized rubber composition.
The obtained unvulcanized rubber composition was press vulcanized at 170 ° C. for 15 minutes to obtain a vulcanized rubber composition.

The following evaluation was performed using the obtained unvulcanized rubber composition and vulcanized rubber composition. Each test result is shown in Tables 3-6. The reference comparative example of Table 3 is Comparative Example 3, the reference comparative example of Table 4 is Comparative Example 10, the reference comparative example of Table 5 is Comparative Example 17, and the reference comparative example of Table 6 is Comparative Example 23. .

(Processability)
With respect to the unvulcanized rubber composition, the Mooney viscosity was measured at 130 ° C. in accordance with the Mooney viscosity measuring method based on JIS K6300. The Mooney viscosity (ML _{1 + 4} ) of the reference comparative example was set to 100, and other blends were indexed by the following formula (Mooney viscosity index). The larger the index, the lower the Mooney viscosity and the better the workability. If the Mooney viscosity index is about 100, it can be said that the processability is sufficiently good.
(Mooney viscosity index) = (ML _{1 + 4} of reference comparative example) / (ML _{1 + 4 of} each formulation) × 100

(Low heat generation)
Using a viscoelastic spectrometer VES (manufactured by Iwamoto Seisakusho Co., Ltd.), the loss tangent (tan δ) of each formulation was measured under the conditions of a temperature of 50 ° C., an initial strain of 10%, and a dynamic strain of 2%. With tan δ being 100, the other blends were indicated by an index according to the following formula (rolling resistance index). The larger the index, the better the rolling resistance characteristics (low heat generation).
(Rolling resistance index) = (tan δ of reference comparative example) / (tan δ of each formulation) × 100

(Abrasion resistance)
Using a Lambourn abrasion tester, the Lambourn abrasion amount was measured under the conditions of a temperature of 20 ° C., a slip ratio of 20% and a test time of 2 minutes. Furthermore, the volume loss amount was calculated from the measured lamborn wear amount, and the lamborn wear index of the reference comparative example was set to 100, and the volume loss amount was indexed by the following formula for the other formulations (Lambourn wear index). It shows that it is excellent in abrasion resistance, so that an index | exponent is large.
(Lambourn wear index) = (volume loss amount of reference comparative example) / (volume loss amount of each formulation) × 100

From Tables 3-6, in the Example which mix | blended the amphoteric compound which has a specific acidic functional group and a specific basic functional group, and carbon black (1), while maintaining favorable workability, abrasion resistance and It was found that the low heat buildup was synergistically improved and the wear resistance and low heat buildup could be significantly improved.
Specifically, the comparison of Comparative Examples 1, 3, 4, and Example 1, the comparison of Comparative Examples 2, 3, 4, and Example 2, the comparison of Comparative Examples 8, 10, 11, and Example 9, and the Comparative Example 9, 10, 11, comparison of Example 10, or comparisons of Comparative Examples 16, 17, 18, and 19 and comparisons of Comparative Examples 22, 23, 24, and Example 23. In addition, the combined use of an amphoteric compound having a specific basic functional group (amphoteric compound A, B, or C) and carbon black (1) synergistically improves wear resistance and low heat build-up. I understood.

Claims (19)

In a method for producing a rubber composition comprising a step of kneading a rubber component, one or more amphoteric compounds and one or more carbon blacks,
The amphoteric compound is composed of a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group. An acidic functional group that is at least one functional group selected from more than one, and a basic functional group that is an amino group or a substituted amino group,
At least one of the carbon blacks has an average boiling point T (° C.) and a specific gravity D (60/60 ° F.) when compared with water of 60 ° F. as a raw material oil for producing the carbon black. The manufacturing method of the rubber composition which is carbon black obtained using the raw material oil whose BMCI value calculated by the following formula | equation is 150 or less and whose aliphatic hydrocarbon ratio is 30 mass% or more.
BMCI = 48640 / (T + 273) + 473.7D-456.8 The method for producing a rubber composition according to claim 1, wherein the amphoteric compound is a compound represented by the following formula (I).

(In formula (I), R ¹ represents an alkylene group having 2 to 30 carbon atoms, an alkenylene group or an alkynylene group. A represents a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group, or a dithiocarboxylic acid group. An acidic functional group that is at least one functional group selected from the group consisting of a group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group, R ² and R ³ These are the same or different and represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, or an alkoxysilyl group having 1 to 20 carbon atoms. The compound represented by the above formula (I) may be a metal salt of the compound.) The method for producing a rubber composition according to claim 2, wherein the amphoteric compound is a compound represented by the following formula (I-1) and / or the following formula (I-2).

(In formula (I-1), p represents an integer of 2 to 8. In formula (I-2), q represents an integer of 2 to 8. Mr ⁺ represents a metal ion, and r represents a valence thereof. Represents.) The rubber composition according to claim 3, wherein the metal ion represented by ^{Mr +} in the formula (I-2) is a lithium ion, a sodium ion, a potassium ion, a cesium ion, a cobalt ion, a copper ion, or a zinc ion. Manufacturing method . The method for producing a rubber composition according to claim 1, wherein the amphoteric compound is at least one selected from the group consisting of (A1), (B1), (C1) and (D1).
(A1): Compound (B1) represented by the following formula (II): Salt (C1) of the compound represented by the following formula (II): Solvate (D1) of the compound represented by the following formula (II) ): Solvate of the salt of the compound represented by the following formula (II)

(In the formula (II), R ¹¹ is an alkanediyl group having 2 to 12 carbon atoms which may have a substituent, a cycloalkanediyl group having 3 to 12 carbon atoms which may have a substituent, or * —B ¹ —Ar—B ² — * group, * represents a bond, B ¹ represents a single bond or an alkanediyl group having 1 to 12 carbon atoms, and B ² represents a single bond or carbon number. Represents an alkanediyl group having 1 to ^12. Ar represents a divalent aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent, and R ¹² and R ¹³ may be the same or different. , A hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, a hydroxy group or an alkoxy group having 1 to 6 carbon atoms, or bonded to each other to represent 2 to 2 carbon atoms Forms an alkanediyl group of 12. R ¹⁴ is a hydroxy group, a carbon number Represents an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an arylalkoxy group having 7 to 15 carbon atoms, or —NR ¹⁵ R ¹⁶ , and R ¹⁵ and R ¹⁶ are the same or different and each represents a hydrogen atom or Represents an alkyl group having 1 to 6 carbon atoms, X represents —NH— or —O—. The method for producing a rubber composition according to claim 5, wherein R ¹² and R ¹³ in the formula (II) are hydrogen atoms. The method for producing a rubber composition according to claim 5 or 6, wherein the compound represented by the formula (II) is a compound represented by the following formula (III).

(In formula (III), R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and X represent the same meaning as described above.) The R ¹¹ is an optionally substituted divalent aromatic hydrocarbon group having 6 to 12 carbon atoms, and the X is —NH—. Of producing a rubber composition. Said R < ¹⁴ > is a hydroxyl group, The manufacturing method of the rubber composition in any one of Claims 5-8. In the said rubber composition , content of the said amphoteric compound is 0.01-30 mass parts with respect to 100 mass parts of carbon black, The manufacturing method of the rubber composition in any one of Claims 1-9. Carbon obtained by using at least one of the carbon blacks as a raw material oil for producing the carbon black having a BMCI value of 95 or more and an aliphatic hydrocarbon ratio of 60% by mass or less It is black, The manufacturing method of the rubber composition in any one of Claims 1-10. The rubber composition according to any one of claims 1 to 11, wherein 10% by mass or more of 100% by mass of the aliphatic hydrocarbon contained in the raw material oil is an animal or vegetable oil or an aliphatic hydrocarbon derived from a modified product thereof . Manufacturing method . The manufacturing method of the rubber composition in any one of Claims 1-12 in which the said raw material oil contains tall oil. The method for producing a rubber composition according to claim 1, wherein at least one of the carbon blacks is carbon black produced by a furnace method . In a rubber composition comprising a rubber component, one or more amphoteric compounds, and one or more carbon blacks,
The amphoteric compound is composed of a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, a thiosulfonic acid group, a dithiocarboxylic acid group, a thioalkylcarboxylic acid group having an alkyl group having 1 to 20 carbon atoms, and a phenolic hydroxyl group. An acidic functional group that is at least one functional group selected from more than one, and a basic functional group that is an amino group or a substituted amino group,
At least one of the carbon blacks has a maximum frequency diameter (Dmod) of the distribution curve of the Stokes equivalent diameter as an aggregate characteristic of 43 to 79 nm, and the ratio of the half width ( ΔD50 ) of the distribution curve to Dmod ( ΔD50 / A rubber composition which is carbon black having a Dmod) of 0.78 to 2.5 . 15. Symbol mounting of the rubber composition is used as a rubber composition for a tire. A pneumatic tire produced using the rubber composition according to claim 16. The method for producing a rubber composition according to claim 1, wherein the rubber composition is used as a tire rubber composition. The manufacturing method of a pneumatic tire including the process of producing a pneumatic tire using the rubber composition obtained by the manufacturing method of the rubber composition of Claim 18.