JP2022061542A - Manufacturing method of carbon black - Google Patents

Abstract

To provide a manufacturing method of carbon black excellent in grip performance, and capable of exhibiting more excellent abrasion resistance when being blended with a rubber composition such as a tire tread rubber composition.SOLUTION: A manufacturing method of carbon black includes: generating a primary reaction product by performing primary reaction of bringing a stock oil having a mass ratio of carbon/hydrogen of 10.0-20.0 into contact with combustion gas obtained by mixing and combusting oxygen-containing gas and fuel so that an oxygen content in the oxygen-containing gas per kg of a supply amount of the stock oil is more than 1.26 Nm3 and 1.80 Nm3 or less; and performing secondary reaction of reacting an addition oil having a mass ratio of carbon/hydrogen of 5.0 or more and less than 10.0 with an amount of 0.30-1.00 time of a mass ratio of the sock oil with the primary reaction product thus obtained.SELECTED DRAWING: None

Description

The present invention relates to a method for producing carbon black.

There are various types of carbon black for rubber reinforcement, depending on the characteristics of the rubber, and these characteristics are the main factors that determine the various performances of rubber. Therefore, when blending into a rubber composition, Carbon black, which has characteristics suitable for member applications, has been selected.

For example, rubber members such as tire treads that require a high degree of reinforcement have conventional high-structured hardware such as SAF (N110) and ISAF (N220) that have a small primary particle size and a large specific surface area. System carbon black is used.

Further, among such rubber members for the tire tread portion, as the rubber member for the tire tread having improved steering stability and wear resistance, the CTAB specific surface area and the 24M4DBP absorption amount are within a specific range, and the 24M4DBP absorption amount and the 24M4DBP absorption amount. Those having a specific relationship with the aggregate density of carbon black have been proposed (see Patent Document 1 (Japanese Unexamined Patent Publication No. 2005-8877)).

Japanese Unexamined Patent Publication No. 2005-8877

In recent years, rubber members with better steering stability (having high grip performance) have been required, but carbon black having a large specific surface area is used as a rubber component in order to improve steering stability (grip performance). If this is the case, there is a technical problem that carbon black tends to aggregate and the dispersibility is lowered, and as a result, the reinforcing property (wear resistance) is easily lowered.

Under such circumstances, the present invention provides a novel method for producing carbon black, which can exhibit excellent grip performance and even more excellent wear resistance when blended in a rubber composition such as a tire tread rubber composition. It is intended to be provided.

As a result of diligent studies by the present inventor in order to solve the above technical problems, a combustion gas obtained by mixing and burning a raw material oil having a carbon / hydrogen mass ratio of 10.0 to 20.0, an oxygen-containing gas and a fuel Is obtained after performing a primary reaction in which the amount of oxygen in the oxygen-containing gas exceeds 1.26 Nm ³ and is 1.80 Nm ³ or less per 1 kg of the raw material oil supply to generate a primary reaction product. A secondary reaction is carried out by reacting the primary reaction product with an additive oil having a carbon / hydrogen mass ratio of 5.0 or more and less than 10.0 in an amount of 0.30 to 1.00 times the mass of the raw material oil. It was found that the above technical problems could be solved by carrying out the above-mentioned techniques, and the present invention was completed based on the present findings.

That is, the present invention
(1) The oxygen-containing gas per 1 kg of the raw material oil supply amount of a raw material oil having a carbon / hydrogen mass ratio of 10.0 to 20.0 and a combustion gas obtained by mixing and burning an oxygen-containing gas and a fuel. After performing a primary reaction in which the oxygen content in the gas exceeds 1.26 Nm ³ and is brought into contact with 1.80 Nm ³ or less to generate a primary reactant,
The added oil having a carbon / hydrogen mass ratio of 5.0 or more and less than 10.0 is reacted with the obtained primary reaction product in an amount of 0.30 to 1.00 times the mass of the raw material oil. A method for producing carbon black, which comprises performing the following reaction.
(2) Using a reactor in which a fuel combustion zone, a raw material introduction zone, and an added oil introduction zone are sequentially provided from the upstream to the downstream direction of the gas flow path.
An oxygen-containing gas and a fuel are introduced into the fuel combustion zone and mixed and burned to generate a high-temperature combustion gas flow, and a raw material oil is introduced while introducing the high-temperature combustion gas flow into the raw material introduction zone to perform a primary reaction. The method for producing carbon black according to (1) above, wherein the secondary reaction is carried out by introducing the additive oil in the additive oil introduction zone after producing the primary reaction product.
(3) The obtained carbon black is
The total active point represented by the product of the full width at half maximum of the Raman scattering peak appearing in the range of 1340 to 1360 cm ^-1 when the excitation wavelength is 532 nm and the specific surface area when nitrogen gas is adsorbed is 8.20. It is more than × 10 ⁴ (cm ^-1・ m ² / g) and less than 11.50 × 10 ⁴ (cm ^-1・ m ² / g).
When the nuclear magnetic resonance signal of the spin-spin relaxation process observed by the solid echo method is represented by the sum of the first signal and the second signal having a time constant larger than that of the first signal, the first signal is described. The carbon black according to (1) or (2) above, wherein the amount of hydrogen represented by the signal intensity per unit mass at time 0 of the signal is 25.0 to 125.0 (/ g). It provides a manufacturing method of.

INDUSTRIAL APPLICABILITY According to the present invention, it is provided a method for producing a novel carbon black capable of exhibiting excellent grip performance and even more excellent wear resistance when blended in a rubber composition such as a tire tread rubber composition. Can be done.

It is a schematic sectional drawing which shows the morphological example of the reaction furnace used in the manufacturing method of carbon black which concerns on this invention. It is explanatory drawing which shows the calculation method of the full width at half maximum of ΔD in the carbon black obtained by the manufacturing method which concerns on this invention. It is a figure for demonstrating the measuring method of Raman spectrum in the carbon black obtained by the manufacturing method which concerns on this invention. It is a figure which shows the example of the T ₂ relaxation curve (free induction decay curve) obtained when the spin-spin relaxation time T ₂ is measured using the pulse nuclear magnetic resonance apparatus in the carbon black obtained by the manufacturing method which concerns on this invention. be. It is a figure which shows the fitting curve of the T ₂ relaxation curve (free induction decay curve) shown in FIG. It is a figure which shows the relationship of the wear amount with respect to the loss coefficient (tan δ) in the case of using the carbon black obtained in the Example and the comparative example of this invention.

In the method for producing carbon black according to the present invention, a raw material oil having a carbon / hydrogen mass ratio of 10.0 to 20.0 and a combustion gas obtained by mixing and burning an oxygen-containing gas and a fuel are used as the raw material oil. After performing a primary reaction for contacting the oxygen-containing gas so that the amount of oxygen in the oxygen-containing gas exceeds 1.26 Nm ³ and 1.80 Nm ³ or less per 1 kg of the supplied amount, a primary reaction product is produced.
The added oil having a carbon / hydrogen mass ratio of 5.0 or more and less than 10.0 is reacted with the obtained primary reaction product in an amount of 0.30 to 1.00 times the mass of the raw material oil. It is characterized by performing the following reaction.

In the method for producing carbon black according to the present invention, the mass ratio of carbon / hydrogen constituting the raw material oil is 10.0 to 20.0, and 10.0 to 18.0 is required to ensure stable reactivity. It is preferably 10.3 to 17.0 in order to secure stable reactivity and high yield.

In the method for producing carbon black according to the present invention, the ratio of the mass of carbon to the mass of hydrogen constituting the raw material oil (mass of carbon / mass of hydrogen) is within the above range, so that a stable reaction can be maintained. Carbon black can be produced in high yield.

In the method for producing carbon black according to the present invention, the carbon / hydrogen mass ratio means a value (mass ratio) calculated based on the mass of carbon and hydrogen measured according to JIS M 8813.

In the method for producing carbon black according to the present invention, the raw material oils include aromatic hydrocarbons such as cyclohexane, benzene, toluene, xylene, naphthalene and anthracene, coal-based hydrocarbons such as cleosetic oil and carboxylic acid oil, and ethylene bottom. List one or more selected from petroleum-based heavy oils such as oil (ethylene heavy end oil) and FCC residual oil, acetylene-based unsaturated hydrocarbons, ethylene-based hydrocarbons, and aliphatic saturated hydrocarbons such as pentane and hexane. Can be done.
In the present invention, the raw material oil may be a mixture of two or more of the above hydrocarbons and the like.

In the method for producing carbon black according to the present invention, a primary reaction is performed in which a raw material oil having a carbon / hydrogen mass ratio of 10.0 to 20.0 is brought into contact with a combustion gas obtained by mixing and burning an oxygen-containing gas and a fuel. To produce a primary reactant.

The combustion gas is a mixture of an oxygen-containing gas and a fuel and burned.
Examples of the oxygen-containing gas include gas consisting of oxygen, air or a mixture thereof, and examples of the fuel include petroleum-based liquid fuels such as hydrogen, carbon monoxide, natural gas, petroleum gas, FCC residual oil, and heavy oil. , Creosort oil and other coal-based liquid fuels.

The supply amount of the raw material oil is not particularly limited, but is preferably 100 kg / hour to 2000 kg / hour, more preferably 150 kg / hour to 1500 kg / hour, and more preferably 200 kg / hour to 1400 kg / hour. More preferred.

The amount of combustion gas supplied to the raw material oil is preferably 2000 Nm ³ / h to 5500 Nm ³ / h, more preferably 2500 Nm ³ / h to 5000 Nm ³ / h, and 3000 Nm ³ / h to 4500 Nm ³ / h. Is more preferable.
When air is used as the oxygen-containing gas in the method for producing carbon black according to the present invention, the feedstock oil supply amount and the air supply amount are such that the air supply amount is 6.1 to 8.3 Nm with respect to the feedstock oil supply amount of 1 kg. It is preferably ³ , and the air supply amount is 6.2 to 7.8 Nm ³ with respect to the raw material oil supply amount of 1 kg, and the air supply amount is 6.2 to 7.8 Nm 3 with respect to the raw material oil supply amount of 1 kg. It is more preferably 7.6 Nm ³ .

In the method for producing carbon black according to the present invention, the raw material oil and the oxygen-containing gas supplied to the primary reaction have an oxygen content of more than 1.26 Nm ³ and 1.80 Nm ³ or less per 1 kg of the raw material oil supply amount. Make contact so that
The raw material oil and oxygen-containing gas supplied to the primary reaction exert a strong affinity with the rubber component when blended in a rubber composition such as a tire tread rubber composition, and the raw material oil supply amount in order to exhibit high grip performance. It is preferable to make contact so that the amount of oxygen in the oxygen-containing gas per 1 kg is 1.28 to 1.74 Nm ³ , and when blended in a rubber composition such as a tire tread rubber composition, it has a stable and strong affinity with the rubber component. In order to exhibit high grip performance, it is more preferable to make contact so that the amount of oxygen in the oxygen-containing gas is 1.30 to 1.64 Nm ³ per 1 kg of raw material oil supply, and the tire tread rubber composition. When blended in a rubber composition such as, the amount of oxygen in the oxygen-containing gas is 1.30 to 1 per 1 kg of raw material oil supply in order to exhibit a stable and strong affinity with the rubber component and to exhibit stable and high grip performance. It is more preferable to bring them into contact so as to be .60 Nm ³ .

In the method for producing carbon black according to the present invention, a raw material oil and an oxygen-containing gas are subjected to a primary reaction so as to satisfy the above range, so that when the rubber is blended into a rubber composition such as a tire tread rubber composition, rubber is produced. It is possible to obtain carbon black having surface properties that exhibit strong binding force (affinity) with the components, and it is possible to easily obtain a rubber composition having a high loss coefficient (excellent grip performance).

In the method for producing carbon black according to the present invention, a primary reaction product is produced by performing a primary reaction in which the raw material oil and the combustion gas are brought into contact with each other, and then the added oil is reacted with the obtained primary reaction product. The next reaction is performed.

In the method for producing carbon black according to the present invention, the mass ratio of carbon / hydrogen constituting the additive oil is 5.0 or more and less than 10.0, and 5.5 to 9. It is preferably 5, and more preferably 5.7 to 9.3 in order to secure stable reactivity and high yield.

In the method for producing carbon black according to the present invention, the ratio of the mass of carbon to the mass of hydrogen constituting the additive oil (mass of carbon / mass of hydrogen) is within the above range, so that the surface has a hydrogen functional group. Carbon black can be easily prepared.

In the method for producing carbon black according to the present invention, the carbon / hydrogen mass ratio means a value (mass ratio) calculated based on the mass of carbon and hydrogen measured according to JIS M 8813.

The additive oil is not particularly limited as long as it is an oily substance containing a hydrogen atom, but a hydrocarbon oil is preferable, and the hydrocarbon oil is an aromatic hydrocarbon such as cyclohexane, benzene, toluene, xylene, naphthalene, and anthracene. One or more selected from acetylene-based unsaturated hydrocarbons, ethylene-based hydrocarbons, aliphatic saturated hydrocarbons such as pentane and hexane, and the like can be mentioned.

In the method for producing carbon black according to the present invention, a secondary reaction is carried out by reacting in an amount such that the amount of the added oil added to the primary reaction product is 0.30 to 1.00 mass times that of the raw material oil, and a stable reaction is carried out. In order to secure the properties, it is preferable to carry out a secondary reaction by reacting in an amount that is 0.31 to 0.95 mass times that of the feedstock oil, and in order to secure stable reactivity and a high yield, the feedstock oil is 0. It is more preferable to carry out the secondary reaction by reacting in an amount of .32 to 0.93 mass times.

In the method for producing carbon black according to the present invention, when the amount of the added oil added is within the above range, it is possible to produce carbon black having a hydrogen functional group on the surface in a high yield while maintaining a stable reaction. can.

In the method for producing carbon black according to the present invention, by introducing and reacting an additive oil with a primary reaction product, a predetermined number of edges serving as active points are formed on the surface, and a desired amount of hydrogen atoms are bonded to the carbon black. Can be easily prepared.

As an embodiment of the method for producing carbon black according to the present invention, a reactor in which a fuel combustion zone, a raw material introduction zone, and an additive oil introduction zone are sequentially provided from upstream to downstream of the gas flow path is used.
An oxygen-containing gas and a fuel are introduced into the fuel combustion zone and mixed and burned to generate a high-temperature combustion gas flow, and a raw material oil is introduced while introducing the high-temperature combustion gas flow into the raw material introduction zone to perform a primary reaction. After producing the primary reaction product, the additive oil is introduced in the additive oil introduction zone to carry out the secondary reaction.

In this case, a reactor in which a fuel combustion zone, a raw material introduction zone, and an additive oil introduction zone are sequentially provided is used from the upstream to the downstream direction of the gas flow path. Examples of such a reactor include a wide-diameter cylindrical reactor as schematically shown in FIG.
Hereinafter, the method for producing carbon black of the present invention will be described using the reactor shown in FIG. 1 as an example.

The reactor shown in FIG. 1 has a fuel combustion zone 3, a raw material introduction and primary reaction zone 5, an added oil introduction zone 8, and a secondary, which communicate from the upstream to the downstream of the gas flow path formed in the reactor. Reaction bands 9 are sequentially provided.

That is, in the reaction furnace shown in FIG. 1, the fuel combustion zone 3 includes an oxygen-containing gas introduction port 1 for introducing an oxygen-containing gas such as air from a direction perpendicular to the furnace axis direction, and combustion for supplying fuel in the furnace axis direction. It is equipped with a burner 2 for use. Further, the raw material introduction and primary reaction zone 5 includes a raw material oil introduction nozzle 4 for supplying raw material oil from a direction perpendicular to the furnace axis direction, and is provided coaxially with the fuel combustion zone 3. Further, the additive oil introduction zone 8 includes an additive oil introduction nozzle 6 for supplying the additive oil from a direction perpendicular to the furnace axis direction, and is provided coaxially with the raw material introduction and the primary reaction zone 5. The secondary reaction zone 9 is provided so as to communicate coaxially with the additive oil introduction zone 8. In the reaction furnace shown in FIG. 1, a reaction stop band is also provided coaxially communicating with the secondary reaction band 9, and the cooling liquid is sprayed into the reaction stop band from the direction perpendicular to the furnace axis direction. A coolant introduction nozzle 7 is provided.

The reactor shown in FIG. 1 has a drum-shaped shape in which the tube is contracted from the fuel combustion zone 3 toward the raw material introduction and primary reaction zone 5, and the tube is expanded from the raw material introduction and primary reaction zone 5 toward the added oil introduction zone 8. However, the shape of the reactor is not limited to such a shape, and various shapes can be adopted.

In the method for producing carbon black of the present invention, oxygen-containing gas and fuel are introduced into the fuel combustion zone 3 and mixed and burned to generate a high-temperature combustion gas flow.
Examples of the oxygen-containing gas include gas consisting of oxygen, air or a mixture thereof, and examples of the fuel include petroleum-based liquid fuels such as hydrogen, carbon monoxide, natural gas, petroleum gas, FCC residual oil, and heavy oil. , Creosort oil and other coal-based liquid fuels.
Examples of the fuel that is a source of combustion gas include the same fuels that can generate the above-mentioned combustion gas.

The supply amount of the oxygen-containing gas in the fuel combustion zone 3 is preferably 2000 Nm ³ / hour to 5500 Nm ³ / hour, more preferably 2500 Nm ³ / hour to 5000 Nm ³ / hour, and 3000 Nm ³ / hour to 4500 Nm. ³ / hour is even more preferred. The fuel supply amount in the fuel combustion zone 3 is preferably 50 kg / hour to 400 kg / hour, more preferably 100 kg / hour to 350 kg / hour, and 150 kg / hour to 300 kg / hour. Is even more preferable.
In the fuel combustion zone 3, for example, by supplying fuel while supplying oxygen-containing gas preheated to 400 ° C. to 600 ° C., both can be mixed and burned to generate a high-temperature combustion gas flow.

In the method for producing carbon black of the present invention, the raw material introduction and the raw material oil are introduced into the raw material introduction and the primary reaction zone 5 from the raw material oil introduction nozzle 4 while introducing the high temperature combustion gas flow into the raw material introduction and the primary reaction zone 5.

Examples of the raw material oil supplied in the raw material introduction and the primary reaction zone 5 include those described above.
Further, as the raw material oil introduction nozzle, a one-fluid nozzle can be mentioned.

The amount of the feedstock oil to be introduced is not particularly limited, but is preferably 100 kg / hour to 2000 kg / hour, more preferably 150 kg / hour to 1500 kg / hour, and more preferably 200 kg / hour to 1400 kg / hour. More preferred.

In the method for producing carbon black according to the present invention, after the raw material introduction and the raw material oil are introduced into the primary reaction zone 5 to perform the primary reaction, the additive oil is introduced into the additive oil introduction zone 8 to carry out the secondary reaction. conduct.

Examples of the additive oil include those similar to those described above.

The amount of the added oil introduced in the added oil introduction zone is preferably 50 to 1500 kg / hour, more preferably 100 to 1200 kg / hour, and even more preferably 150 to 1000 kg / hour.
When the amount of added oil introduced in the added oil introduction zone is within the above range, the amount of hydrogen on the obtained carbon black surface can be controlled within a desired range.

When the reaction furnace shown in FIG. 1 is used in the method for producing carbon black of the present invention, after the raw material is introduced and the primary reaction is carried out in the primary reaction zone 5, the additive oil is introduced in the additive oil introduction zone 8 and the additive oil is introduced. By causing a secondary reaction in the introduction band 8 or the secondary reaction band 9 in the introduction, the desired carbon black can be easily prepared.
In the method for producing carbon black of the present invention, a reaction furnace having no secondary reaction zone 9 may be used.

In the reaction furnace shown in FIG. 1, the carbon black-containing gas is introduced into the reaction stop zone and the coolant is sprayed.
Examples of the cooling liquid include water, and by spraying the cooling liquid, the carbon black particles suspended and suspended in the high-temperature combustion gas are cooled. The cooling liquid can be sprayed, for example, by spraying the cooling liquid from the cooling liquid introduction nozzle 7 shown in FIG.

Next, the cooled carbon black particles can be recovered by separating and collecting the cooled carbon black particles by a collection system (separation and collection device) such as a cyclone or a bag filter via a flue or the like. ..

In the method for producing carbon black of the present invention, the total number of active points and the amount of hydrogen of the obtained carbon black can be easily adjusted within a desired range by changing the type and amount of the added oil to be reacted with the primary reactant. ..

Examples of the carbon black obtained by the production method of the present invention include the same as those described in detail in the description of the carbon black of the present invention.

INDUSTRIAL APPLICABILITY According to the present invention, it is provided a method for producing a novel carbon black capable of exhibiting excellent grip performance and even more excellent wear resistance when blended in a rubber composition such as a tire tread rubber composition. Can be done.

Next, the carbon black obtained by the production method of the present invention will be described.
The carbon black obtained by the production method of the present invention is
The total active point represented by the product of the full width at half maximum of the Raman scattering peak appearing in the range of 1340 to 1360 cm ^-1 when the excitation wavelength is 532 nm and the specific surface area when nitrogen gas is adsorbed is 8.20. It is more than × 10 ⁴ (cm ^-1・ m ² / g) and less than 11.50 × 10 ⁴ (cm ^-1・ m ² / g).
When the nuclear magnetic resonance signal of the spin-spin relaxation process observed by the solid echo method is represented by the sum of the first signal and the second signal having a time constant larger than that of the first signal, the first signal is described. The amount of hydrogen represented by the signal intensity per unit mass at time 0 of the signal is 25.0 to 125.0 (/ g).
More specifically, the carbon black obtained by the production method according to the present invention has the following formula (I).
ΔD × N ₂ SA (I)
(However, ΔD is the half-value full width (cm ^-1 ) of the peak having a peak top in the range of 1350 ± 10 cm ^-1 in the Raman spectrum obtained when measured at an excitation wavelength of 532 nm using a laser Raman spectroscope. , N ₂ SA is the nitrogen adsorption specific surface area (m ² / g) measured by the nitrogen adsorption method.)
The total active site represented by is more than 8.20 × 10 ⁴ (cm ^-1 · m ² / g) and 11.50 × 10 ⁴ (cm ^-1 · m ² / g) or less.
The T ₂ relaxation curve (free induction decay curve) obtained when the spin-spin relaxation time T ₂ is measured with the observed nucleus as ¹ H by the solid echo method using a pulse nuclear magnetic resonance device is given by the following equation f (t).
f (t) = A (1) exp (-t / T ₂ (1)) + A (2) exp (-t / T ₂ (2))
(However, T ₂ (1) is the relaxation time of the component having a short relaxation time, T ₂ (2) is the relaxation time of the component having a long relaxation time, and A (1) is the relaxation time of the component having a short relaxation time at t = 0. Signal strength, A (2) is the signal strength at t = 0 of the component with a long relaxation time)
When represented by
The following formula (II)
A (1) / w (II)
(However, w is the mass (g) of the measurement sample.)
It is characterized in that the amount of hydrogen represented by is 25.0 to 125.0 (/ g).

In the carbon black obtained by the production method according to the present invention, the full width at half maximum (full width at half maximum ΔD) is in the range of 1350 ± 10 cm ^-1 in the Raman spectrum obtained when measured at an excitation wavelength of 532 nm using a laser Raman spectroscope. The full width at half maximum (cm ^-1 ) of the peak having a peak top at.

The full width at half maximum (full width at half maximum ΔD) is preferably 180 to 280 cm ^-1 , more preferably 185 to 270 cm ^-1 , and even more preferably 188 to 265 cm ^-1 .
In the carbon black obtained by the production method according to the present invention, the half-value full width (half-value full width ΔD) is within the above range, so that the number of active points on the surface of the carbon black is controlled within a desired range, and ΔD × N ₂ SA described later. Can be easily controlled within a desired range, and the aggregation of carbon black can be suppressed and the dispersibility can be easily improved when blended in the rubber component.

FIG. 2 is a diagram showing a method of calculating a full width at half maximum (full width at half maximum ΔD) in carbon black obtained by the production method according to the present invention.
As shown in FIG. 2, the carbon black obtained by the production method according to the present invention has a peak top in the range of 1350 ± 10 cm ^-1 in the Raman spectrum obtained by measuring at an excitation wavelength of 532 nm by laser Raman spectroscopy. A peak with is detected.
Then, the measurement wavelength at the peak top position is set to Dmax (cm ^-1 ), and in the obtained spectrum, the detection position on the low wavelength (low Raman shift) side having half the detection intensity of the peak intensity at Dmax is D50 ( When cm ^-1 ), the value calculated by the following formula is defined as the full width at half maximum ΔD (cm ^-1 ) in the present application.
ΔD = (Dmax-D50) × 2

In the above Raman spectrum, a peak having a peak top in the range of 1350 ± 10 cm ^-1 corresponds to a peak in the D band of the Raman spectrum.
According to the study by the present inventors, the half-value full width ΔD of the peak of the D band indicates the degree of disorder of the crystal structure on the carbon black surface, and therefore, it is carbon that ΔD is within the desired range in the present invention. It means that there are many edges (active points) on the black surface, that is, functional groups showing affinity for the rubber component.

In the present invention, the full width at half maximum ΔD (cm ^-1 ) means a value calculated from a Raman spectrum obtained by performing the data processing of (2) after measuring under the measurement condition of (1) below.
(1) Using HR-800 manufactured by HORIBA, Ltd. as a laser Raman spectroscope, several carbon black samples to be measured were placed on a slide glass and rubbed several times with a spatula to flatten the surface. The thing is measured under the following measurement conditions.
YAG laser (excitation wavelength): 532 nm
Number of engraved lines: 600 gr / mm
Filter: D0.6
Objective lens magnification: 100 times Exposure time: 150 seconds Total number of times: 2 times An example of the spectrum obtained at this time is shown in FIG.
(2) The signal intensity at the measurement wavelength (Raman Shift) 2100 cm ^-1 of the obtained spectrum is set to 0, the average value is obtained for each of 39 adjacent data points constituting the spectrum, and then smoothing processing is performed to obtain the above. Obtain a spectral curve connecting each average value. Next, in order to facilitate comparison for each sample, the peak top intensity observed in the measurement wavelength range of 1350 ± 10 cm ^-1 is set to 100.
An example of Raman spectrum obtained at this time is a Raman spectrum as illustrated in FIG.

In the carbon black obtained by the production method according to the present invention, N ₂ SA is the nitrogen adsorption specific surface area (m ² / g) of the carbon black measured by the nitrogen adsorption method.

In the carbon black obtained by the production method according to the present invention, N ₂ SA is preferably 345 to 565 m ² / g, more preferably 355 to 555 m ² / g, and 360 to 550 m ² / g. It is more preferable to have.

In the carbon black obtained by the production method according to the present invention, when N ₂ SA is within the above range, the number of active points on the surface of the carbon black is controlled within a desired range, and the half-value full width and the nitrogen adsorption specific surface area, which will be described later, are defined. The product (ΔD × N ₂ SA) can be easily controlled within a desired range, and the dispersibility of carbon black can be improved when blended with the rubber component to easily improve the wear resistance.

In this application document, N ₂ SA means a value measured by the amount of nitrogen adsorbed in accordance with the method specified in JIS K6217-1 2001 "Test method for basic performance of carbon black for rubber". ..

In the carbon black obtained by the production method according to the present invention, the following formula (I)
ΔD × N ₂ SA (I)
(However, ΔD is the half-value full width (cm ^-1 ) of the peak having a peak top in the range of 1350 ± 10 cm ^-1 in the Raman spectrum obtained when measured at an excitation wavelength of 532 nm using a laser Raman spectroscope. , N ₂ SA is the nitrogen adsorption specific surface area (m ² / g) measured by the nitrogen adsorption method.)
The total active sites represented by are more than 8.20 × 10 ⁴ (cm ^-1 · m ² / g) and 11.500 × 10 ⁴ (cm ^-1 · m ² / g) or less.

The total active point represented by the above formula (I) is more than 8.20 × 10 ⁴ (cm ^-1 · m ² / g) and 11.50 × 10 ⁴ (cm ^-1 · m ² / g) or less. Yes, 8.25 × 10 ⁴ to 11.45 × 10 ⁴ (cm ^-1・ m ² / g) is preferable, and 8.30 × 10 ⁴ to 11.40 × 10 ⁴ (cm ^-1・ m ² / g) is preferable. ) Is more preferable.
When trying to obtain carbon black with excellent workability, the total active point of carbon black represented by the above formula (I) exceeds 9.50 × 10 ⁴ (cm ^-1 · m ² / g) 11 .50 × 10 ⁴ (cm ^-1 · m ² / g) or less is preferable, 9.55 × 10 ⁴ to 11.45 × 10 ⁴ (cm ^-1 · m ² / g) is more preferable, and 9.60 × 10 ⁴ to 11.40 × 10 ⁴ (cm ^-1 · m ² / g) is more preferable.

When the total active site represented by the above formula (I) (the total active site represented by the above formula (I)) is within the above range, the workability is excellent and the binding force (affinity) with the rubber component is appropriate. It is possible to obtain carbon black that exhibits (sexuality).

The carbon black obtained by the production method according to the present invention is a T ₂ relaxation curve obtained when the spin-spin relaxation time T ₂ is measured by the solid echo method using a pulse nuclear magnetic resonance apparatus with the observed nucleus as ¹ H. The free induction decay curve) is given by the following equation f (t).
f (t) = A (1) exp (-t / T ₂ (1)) + A (2) exp (-t / T ₂ (2))
(However, T ₂ (1) is the relaxation time of the component having a short relaxation time, T ₂ (2) is the relaxation time of the component having a long relaxation time, and A (1) is the relaxation time of the component having a short relaxation time at t = 0. Signal strength, A (2) is the signal strength at t = 0 of the component with a long relaxation time)
When represented by
The following formula (II)
A (1) / w (II)
(However, w is the mass (g) of the measurement sample.)
The amount of hydrogen represented by is 25.0 to 125.0 (/ g).

The amount of hydrogen represented by the above formula (II) is 25.0 to 125.0 (/ g).
It is preferably 40.0 to 110.0 (/ g), more preferably 50.0 to 100.0 (/ g).

In the carbon black obtained by the production method according to the present invention, the amount of hydrogen represented by A (1) / w (II) is within the above range, so that good dispersibility is exhibited when kneading into rubber. At the same time, a rubber composition having a high loss coefficient (excellent in grip performance) can be easily prepared.

On the other hand, as described above, the carbon black obtained by the production method according to the present invention is different from carbon black because the total active points (total active points represented by the above formula (I)) are within a predetermined range. An appropriate bonding force (affinity) with the rubber component can be obtained.
Therefore, the production according to the present invention, wherein the total active points (total active points represented by the above formula (I)) and the above hydrogen amount (the amount of hydrogen represented by the above formula (II)) are each within a predetermined range. The carbon black obtained by the method has a high loss coefficient (high grip performance) and excellent steering stability when used as a constituent component of a rubber composition, and has an appropriate bonding force (affinity) with the rubber component. Excellent wear resistance can be easily exhibited.

In the present invention, the amount of hydrogen (the amount of hydrogen represented by the above formula (II)) is determined by the following method.
(1) Using Minispec mq20 of Bruker Biospin Co., Ltd. as a pulse nuclear magnetic resonance apparatus, the carbon black to be measured was dried at 110 ° C. for 30 minutes, and then 0.2 g of a glass sample tube was filled. Using a sample, spin-spin relaxation time (lateral relaxation time) T ₂ is measured under the following measurement conditions to obtain a T ₂ relaxation curve (free induction decay curve).
<Measurement conditions>
Nuclide to be measured: ¹ H
Pulse mode: Solid echo method (90 ° × -τ-90 ° y)
90 ° pulse width: 2.7 μs
Measurement time: 2 ms
Waiting time: 500ms
Number of integrations: 52 times Measurement temperature: 40 ° C
Gain: 90
Since the mass of carbon black is constant at 0.2 g and the device function is also constant (Gainn = ⁹⁰ ), the signal intensity of the obtained T ₂ relaxation curve (free induction decay curve) is proportional to the 1H concentration to be measured. Will increase or decrease.
(2) The obtained free induction decay curve is obtained by a linear least squares method using the fitting software (TD-NMR-A for Windows 7) attached to the pulse nuclear magnetic resonance apparatus (Bruker Biospin Co., Ltd. Minispec mq20). By fitting, the following formula f (t)
f (t) = A (1) exp (-t / T ₂ (1)) + A (2) exp (-t / T ₂ (2))
(However, T ₂ (1) is the relaxation time of the component having a short relaxation time, T ₂ (2) is the relaxation time of the component having a long relaxation time, and A (1) is the relaxation time of the component having a short relaxation time at t = 0. Signal strength, A (2) is the signal strength at t = 0 of the component with a long relaxation time)
Obtain the approximate curve represented by.
(3) The signal strength A (1) is divided by the mass w (g) of the measurement sample.

FIG. 4 shows an example of the T ₂ relaxation curve (free induction decay curve) obtained by the above method.
As shown in FIG. 4, when the time excited by the 90 ° pulse is t = 0, it can be seen that a signal in which the magnetization (signal intensity) in the y-axis direction is attenuated with time can be obtained.
FIG. 5 shows the fitting curve when the T ₂ relaxation curve (free induction decay curve) shown in FIG. 4 is fitted by the linear least squares method, and is shown by a solid line. As shown in FIG. 5, the obtained T ₂ is shown. The relaxation curve (free lead decay curve) can be expressed as the sum of two exponential functions by fitting.
Here, since the liquid and the solid can be distinguished by the difference in the time constant, the signal intensity A (1) at t = 0 (when excited by a 90 ° pulse) is the carbon black surface in the exponential function related to the component having a short relaxation time. It can be identified as a hydrogen atom (-COOH, -OH, -H on the surface, -H in the carbon skeleton, etc.). Similarly, in the exponential function relating to the component having a short relaxation time, the signal intensity A (2) at t = 0 (when excited by a 90 ° pulse) is water adsorbed on the carbon black surface, a liquid polycyclic aromatic hydrocarbon compound, or the like. Can be specified.
By dividing the signal intensities A (1) (au) by the mass w (0.2 g) of the carbon black used for the measurement, the amount of hydrogen “A (1) / w” per unit mass of the carbon black is obtained. You can ask.
According to the study by the present inventors, the amount of hydrogen represented by the above formulas (II) (A (1) / w) is a thermal decomposition method conventionally known as a method for measuring the amount of hydrogen on the surface of carbon black. It has been found that it shows a high correlation with the amount of hydrogen obtained by, and for this reason, it can be suitably used as an index showing the amount of hydrogen on the surface of carbon black.

The carbon black obtained by the production method according to the present invention preferably has a DBP (Dibutylphthalate) absorption amount of 80 to 140 cm ^3/100 g, more preferably 85 to 130 cm ^3/100 g, and 90 to 125 cm ³ It is more preferably / 100 g.

The amount of DBP absorbed is an index showing the degree of development of the structure, that is, the degree of complexity of the aggregate structure.
When the amount of DBP absorbed is less than 80 ml / 100 g, the dispersibility of carbon black deteriorates when blended in the rubber composition, and the reinforcing property of the obtained rubber tends to decrease, and when it exceeds 140 ml / 100 g, the rubber composition tends to deteriorate. When blended in, the rubber composition may become hard and the workability may deteriorate.

In this application document, the DBP absorption amount means a value measured by the method specified in JIS K6217-4 "Carbon black for rubber-Basic characteristics-Part 4, How to obtain the DBP absorption amount".

INDUSTRIAL APPLICABILITY According to the present invention, it is provided a method for producing a novel carbon black capable of exhibiting excellent grip performance and even more excellent wear resistance when blended in a rubber composition such as a tire tread rubber composition. Can be done.

Next, the present invention will be described in more detail with reference to examples, but this is merely an example and does not limit the present invention.

(Examples 1 to 6, Comparative Examples 1 to 5)
(Example 1)
Carbon black was produced using a reactor having a substantially cylindrical shape as shown in FIG.
The reactor shown in FIG. 1 has a fuel combustion zone 3, a raw material introduction and primary reaction zone 5, an added oil introduction zone 8, and a secondary, which communicate from the upstream to the downstream of the gas flow path formed in the reactor. The reaction band 9 and the reaction stop band are sequentially provided.

In the reactor shown in FIG. 1, the fuel combustion zone 3 includes an oxygen-containing gas introduction port 1 for introducing an oxygen-containing gas such as air from a direction perpendicular to the furnace axis direction, and a combustion burner for supplying fuel in the furnace axis direction. It is equipped with 2. Further, the raw material introduction and primary reaction zone 5 is provided with a one-fluid nozzle which is a raw material oil introduction nozzle 4 for supplying raw material oil from a direction perpendicular to the furnace axis direction, and is provided coaxially with the fuel combustion zone 3. ing.
The additive oil introduction zone 8 includes a one-fluid nozzle which is an additive oil introduction nozzle 6 for supplying the additive oil from a direction perpendicular to the furnace axis direction, and is provided coaxially with the raw material introduction and the primary reaction zone 5. Further, the secondary reaction band 9 is provided coaxially with the additive oil introduction band 8. Further, the reaction stop zone is provided with a coolant introduction nozzle 7 (water-cooled quench) that can be repositioned in the vertical direction in the figure that supplies cooling water from a direction perpendicular to the furnace axis direction, and is coaxial with the secondary reaction zone 9. It is provided in communication.

As shown in FIG. 1, in the reaction furnace, before and after the raw material introduction and the primary reaction zone 5, the fuel combustion zone 3 is gradually contracted toward the raw material introduction and the primary reaction zone 5, and the raw material introduction and the primary reaction are performed. It has a drum-shaped throttle shape that expands in a tapered shape from the band 5 toward the additive oil introduction band 8.

In the fuel combustion zone 3, 4100 Nm ³ / h of air preheated to 500 ° C. (oxygen content ratio 21% by volume) is supplied from the oxygen-containing gas introduction port 1, and FCC residual oil is supplied as fuel oil from the combustion burner 2. (Petroleum-based residual oil) 250 kg / h was injected and supplied, and mixed combustion was performed to form a high-temperature combustion gas flow flowing in the direction of the furnace axis.

While introducing the raw material introduction and the high temperature combustion gas flow into the primary reaction zone 5, 675 kg of ethylene bottom oil having a carbon / hydrogen mass ratio of 12.0 as the raw material oil from the one fluid nozzle which is the raw material oil introduction nozzle 4. A carbon black-containing gas is supplied at / h, and then, in the additive oil introduction zone, cyclohexane having a carbon / hydrogen mass ratio of 6.0 is supplied from the additive oil introduction nozzle 6 at 225 kg / h and reacted in sequence, thereby causing a carbon black-containing gas. Was generated.
At this time, the amount of oxygen in the air (4100 (Nm ³ / h) × 0.21 / 675 (kg / h)) per 1 kg of the raw material oil supply was 1.28.

Next, the carbon black-containing gas generated in the additive oil introduction zone 8 through the introduction of the raw material and the primary reaction zone 5 is introduced into the secondary reaction zone 9 for further sufficient reaction, and then introduced into the reaction stop zone for cooling. Cooling water was sprayed from the liquid introduction nozzle 7. The cooled carbon black particles were collected by a separation and collection device (not shown) via a flue or the like, and the target carbon black was recovered.

Table 1 shows the types of raw material oil and additive oil used, the mass ratio of carbon / hydrogen, and the amount of additive oil used with respect to the raw material oil in the above reaction, as well as the air supply amount, fuel supply amount, raw material oil supply amount, and addition. The amount of oil supplied is shown in Table 2.
Further, in the obtained carbon black, ΔD, nitrogen adsorption specific surface area N ₂ SA (m ² / g), total active point (ΔD × N ₂ SA), hydrogen amount (A (1) / w) and DBP absorption amount. (Ml / 100g) is shown in Table 3.

(Examples 2 to 6, Comparative Examples 1 to 5)
In Example 1, carbon black was prepared in the same manner as in Example 1 except that the reaction conditions were changed as described in Tables 1 and 2, respectively.
ΔD, nitrogen adsorption specific surface area N ₂ SA (m ² ) in the obtained carbon black
/ G), total active site (ΔD × N ₂ SA), hydrogen amount (A (1) / w) and DBP absorption amount (ml / 100 g) are shown in Table 3.

(Examples 7 to 12, Comparative Examples 6 to 9)
In Example 1, carbon black was prepared in the same manner as in Example 1 except that the reaction conditions were changed as described in Tables 4 and 5, respectively.
ΔD, nitrogen adsorption specific surface area N ₂ SA (m ² / g), total active point (ΔD × N ₂ SA), hydrogen amount (A (1) / w) and DBP absorption amount (ml) in the obtained carbon black. / 100g) is shown in Table 6.

(Production example of rubber composition)
As shown in Table 7, 100 parts by mass of natural rubber (RSS # 1) as a rubber component, 45 parts by mass of any carbon black obtained in the above Examples and Comparative Examples, 3 parts by mass of stearic acid, an antioxidant. (Antage 6C manufactured by Kawaguchi Chemical Industry Co., Ltd.) 1 part by mass and 4 parts by mass of rubber were kneaded with a closed mixer (MIXTRON BB-2 manufactured by Kobe Steel Co., Ltd.). By kneading 0.5 parts by mass of the vulcanization accelerator (Axel NS manufactured by Kawaguchi Chemical Industry Co., Ltd.) and 1.5 parts by mass of sulfur with an open roll, a rubber composition having the composition shown in Table 7 can be obtained. Obtained.

Then, each of the obtained rubber compositions was vulcanized for 45 minutes under a temperature condition of 145 ° C. to form a vulcanized rubber.
Using the obtained vulcanized rubber, the amount of wear, the loss coefficient (tan δ) and the Mooney viscosity Mv (M) were measured by the methods shown below. The results are shown in Table 8.
In Table 8, the results of the wear amount and the loss coefficient (tan δ) are shown for each of the examples and comparative examples in which each of the carbon blacks used was obtained.

<Amount of wear>
Using a Ramborn wear tester (mechanical slip mechanism, AB-1152 manufactured by Ueshima Seisakusho Co., Ltd.), in accordance with the method specified in JIS K6264 "Vulcanized rubber and thermoplastic rubber-How to determine wear resistance-", It was measured under the following measurement conditions.
Specimen: Thickness 10 mm, outer diameter 48 mm
Abrasive paper: Particle size A80
Slip rate: 10%
Specimen surface velocity: 72 m / min
Test load: 3 kg
As for the amount of wear, the smaller the value, the better the wear resistance.

<Loss coefficient (tanδ)>
Using a test piece with a thickness of 2 mm, a length of 40 mm, and a width of 4 mm cut out from each of the obtained vulcanized rubber, a viscoelastic spectrometer (VR-7110 manufactured by Ueshima Seisakusho Co., Ltd.) was used, and the frequency was 50 Hz. The loss coefficient (tan δ) was measured under the measurement conditions of a strain rate of 1.26% and a measurement temperature of 60 ° C.
The loss coefficient (tan δ) indicates that the larger the value, the higher the grip performance.

<Moony viscosity>
Using a Mooney viscometer (AM-3 manufactured by Toyo Seiki Seisakusho Co., Ltd.), preheat the unvulcanized rubber composition at 130 ° C. for 1 minute in accordance with JIS K6300, and then Mooney 4 minutes after the start of rotation of the rotor. Viscosity Mv (M) was measured.
The smaller the value of Mooney viscosity Mv (M), the better the workability.

Further, FIG. 6 shows the amount of wear with respect to the loss coefficient (tan δ) of the vulcanized rubber produced by using the carbon blacks obtained in Examples 1 to 12 and Comparative Examples 1 to 9 respectively.

From the results of Table 3, Table 6, Table 8 and FIG. 6, the vulcanized rubber produced by using the carbon blacks obtained in Examples 1 to 12 by the production method according to the present invention is ΔD ×. Since carbon black is used in which the total active point represented by N ₂ SA and the amount of hydrogen represented by A (1) / w are within the predetermined ranges, the loss coefficient tan δ is large and the grip performance is excellent and the wear is excellent. It can be seen that the amount is small and the wear resistance is excellent (high grip performance and wear resistance can be achieved at the same time).
Further, it can be seen that the vulcanized rubbers produced by using the carbon blacks obtained in Examples 7 to 12 each have a low Mooney viscosity Mv value and are excellent in processability.

On the other hand, from the results of Table 3, Table 6, Table 8 and FIG. 6, the vulcanized rubber produced by using the comparative carbon blacks obtained in Comparative Examples 1 to 9 was ΔD × N as carbon black. ₂ Since the total active point represented by SA or the amount of hydrogen represented by A (1) / w is out of the predetermined range, the loss coefficient tan δ is small and the grip performance is low when blended in the rubber composition. It can be seen that the amount of wear is large and the wear resistance is inferior (high grip performance and wear resistance cannot be achieved at the same time), or the Mooney viscosity Mv value is high and the workability is inferior.

According to the present invention, it is possible to provide a novel carbon black capable of exhibiting excellent grip performance and even more excellent wear resistance when blended in a rubber composition such as a tire tread rubber composition.

1 Oxygen-containing gas introduction port 2 Combustion burner 3 Fuel combustion zone 4 Raw material oil introduction nozzle 5 Raw material introduction and primary reaction zone 6 Additive oil introduction nozzle 7 Coolant introduction nozzle 8 Additive oil introduction zone 9 Secondary reaction zone

Claims (3)

A raw material oil having a carbon / hydrogen mass ratio of 10.0 to 20.0 and a combustion gas obtained by mixing and burning an oxygen-containing gas and a fuel are mixed with oxygen in the oxygen-containing gas per 1 kg of the raw material oil supply amount. After performing a primary reaction in which the amounts are contacted so as to exceed 1.26 Nm ³ and 1.80 Nm ³ or less to generate a primary reactant,
The added oil having a carbon / hydrogen mass ratio of 5.0 or more and less than 10.0 is reacted with the obtained primary reaction product in an amount of 0.30 to 1.00 times the mass of the raw material oil. A method for producing carbon black, which comprises performing the following reaction. Using a reactor in which a fuel combustion zone, a raw material introduction zone, and an additive oil introduction zone are sequentially provided from the upstream to the downstream of the gas flow path, the reactor is used.
An oxygen-containing gas and a fuel are introduced into the fuel combustion zone and mixed and burned to generate a high-temperature combustion gas flow, and a raw material oil is introduced while introducing the high-temperature combustion gas flow into the raw material introduction zone to perform a primary reaction. The method for producing carbon black according to claim 1, wherein after the primary reaction product is produced, the additive oil is introduced in the additive oil introduction zone to carry out the secondary reaction. The resulting carbon black is
The total active point represented by the product of the full width at half maximum of the Raman scattering peak appearing in the range of 1340 to 1360 cm ^-1 when the excitation wavelength is 532 nm and the specific surface area when nitrogen gas is adsorbed is 8.20. It is more than × 10 ⁴ (cm ^-1・ m ² / g) and less than 11.50 × 10 ⁴ (cm ^-1・ m ² / g).
When the nuclear magnetic resonance signal of the spin-spin relaxation process observed by the solid echo method is represented by the sum of the first signal and the second signal having a time constant larger than that of the first signal, the first signal is described. The carbon black according to claim 1 or 2, wherein the amount of hydrogen represented by the signal intensity per unit mass at time 0 of the signal is 25.0 to 125.0 (/ g). Production method.

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