KR102394357B1 - Multi-walled carbon nanotube, method for producing multi-walled carbon nanotube, dispersion liquid, resin composition, and coating film - Google Patents

Abstract

Provided are a multi-walled carbon nanotube capable of obtaining a resin composition with high jet black properties, a method for producing a multi-walled carbon nanotube, a dispersion liquid, a resin composition, and a coating film.
A multi-walled carbon nanotube characterized by satisfying the following requirements (1) and (2).
(1) The average outer diameter of the multi-walled carbon nanotubes is 10 nm or less
(2) The standard deviation of the outer diameter of the multi-walled carbon nanotube is 4 nm or less

Description

Multi-walled carbon nanotube, method for producing multi-walled carbon nanotube, dispersion liquid, resin composition, and coating film

The present invention relates to a multi-walled carbon nanotube and a method for producing a multi-walled carbon nanotube. More specifically, it relates to a multi-walled carbon nanotube, a resin composition containing a multi-walled carbon nanotube and a resin, a dispersion liquid thereof, and a coating film having excellent jet black properties applied thereto.

Carbon nanotubes are cylindrical carbon materials with an outer diameter of several nanometers to several tens of nanometers. Carbon nanotubes have high conductivity and mechanical strength. Therefore, carbon nanotubes are expected to be utilized in various fields such as electronic engineering and energy engineering as a functional material. Examples of the functional material include fuel cells, electrodes, electromagnetic wave shielding materials, conductive resins, members for field emission displays (FEDs), and materials for storing various gases including hydrogen.

On the other hand, as examples of development of the functional material, there are few examples in which carbon nanotubes are used as a color material. For the color material, carbon black is used instead of carbon nanotubes. For example, as shown in Patent Documents 1 and 2, carbon black is used to obtain jet-black resin coatings, films, and moldings. Carbon black can be uniformly dispersed in a resin solution or solid resin.

However, a color material made of carbon black tends to have a high brightness (L*) (ie gray/white). Also, the chromaticity (a *, b *) is in the positive direction (+ a *: red + b *: yellow). Here, L*, a*, and b* represent the values of the L*a*b* color space specified in JIS Z8781-4. For this reason, it was difficult for carbon black to express the so-called 'piano black' and the 'wet fur color of a crow'.

In addition, the color of a molding using carbon black tends to change depending on the primary particle size of carbon black. Specifically, when carbon black having a small primary particle diameter is used, blue light is displayed, but blackness is lowered. As such, in the conventional black material, there is a trade-off relationship between blackness and blue light. For this reason, it was difficult to reproduce a color tone with a bluish light and a high degree of blackness, that is, a tone of jet black.

Patent Documents 3, 4 and 5 relate to adjustment of blackness of a color material made of carbon black. When adjusting the blackness, for example, colloidal properties such as carbon black particle size and aggregated particle size are changed. Further, carbon black is subjected to surface treatment such as ozone oxidation and nitric acid oxidation. By this treatment, the dispersion state in the dispersion is controlled.

Moreover, the method of adding organic pigments, such as phthalocyanine blue, to carbon black is also known. In this way, the color material can appear blue as well as black. However, the blackness deteriorates with the addition of organic pigments in the color material. Therefore, when a molded object containing such a color material is observed under direct sunlight, a red light is observed on the molded object. This problem is recognized as the occurrence of the so-called bronze phenomenon.

Patent Documents 6 and 7 are examining a carbon nanotube laminate in order to solve such a problem. However, in such a means, it is necessary to form a layer so as to obtain the gloss of the resin composition containing carbon nanotubes. Moreover, although patent document 8 also examined carbon nanotube as a jet-black pigment, the outer diameter was large and the jet-black property at the time of coating film was inadequate. In addition, although single-walled carbon nanotubes and double-layered carbon nanotubes with small outer diameters have been developed, dispersion is difficult and it is difficult to achieve a sufficient jet-black feeling.

Further, in Patent Document 9, carbon nanotubes with excellent resin dispersibility are manufactured by reducing entanglement during carbon nanotube synthesis by refining the catalyst to widen the pores in the carbon nanotube aggregate structure. However, carbon nanotubes with a small outer diameter could not be efficiently obtained.

Japanese Patent Laid-Open No. 2001-179176 Japanese Patent Laid-Open No. 2004-098033 Japanese Patent Laid-Open Publication No. 6-122834 Japanese Patent Laid-Open No. 6-136287 Japanese Patent Laid-Open No. 2008-285632 Japanese Patent Laid-Open No. 2016-13680 Japanese Patent Laid-Open No. 2016-22664 Japanese Patent Laid-Open No. 2015-229706 Japanese Patent Laid-Open No. 2008-173608

The technical problem to be achieved by the present invention is to solve the above conventional problems, and to provide a multi-walled carbon nanotube and a method for synthesizing a multi-walled carbon nanotube capable of obtaining a resin composition with high jet-black properties.

As a result of intensive research, the present inventors have found that the above problems can be solved by a specific multi-walled carbon nanotube.

That is, the present invention relates to a multi-walled carbon nanotube characterized in that the following requirements (1) and (2) are satisfied.

(1) The average outer diameter of the multi-walled carbon nanotubes is 10 nm or less

(2) The standard deviation of the outer diameter of the multi-walled carbon nanotube is 4 nm or less

In one embodiment of the multi-walled carbon nanotube, a peak exists at a diffraction angle of 2θ=25°±2° in powder X-ray diffraction analysis, and the half width of the peak is 3° or more and 5° or less.

In another embodiment of the multi-walled carbon nanotube, a peak exists at a diffraction angle of 2θ=25°±2° in powder X-ray diffraction analysis, and the half width of the peak is 5° or more and 5.5° or less.

In one embodiment of the multi-walled carbon nanotube, when the average outer diameter of the multi-walled carbon nanotube is X and the standard deviation of the outer diameter of the multi-walled carbon nanotube is σ, X±2σ satisfies 2.5 nm ≤ X±2σ ≤ 15.5 nm .

In an embodiment of the multi-walled carbon nanotube, when the maximum peak intensity in the range of 1560 to 1600 cm ^-1 is G and the maximum peak intensity in the range of 1310 to 1350 cm ^-1 is D in the Raman spectrum, G/ D ratio is 2.0 or less, Preferably it is 1.0 or less.

The method for producing a multi-walled carbon nanotube of the present invention includes the following steps.

(1) an active ingredient containing at least one selected from cobalt, nickel, and iron, and a catalyst carrier containing at least one selected from magnesium, aluminum and silicon are mixed and/or pulverized, then calcined to obtain a catalyst process to get

(2) a step of obtaining multi-walled carbon nanotubes by bringing the catalyst into contact with a carbon source containing at least one selected from hydrocarbons and alcohols under heating

In an embodiment of the method for manufacturing the multi-walled carbon nanotube, in the step (2), the carbon source includes a hydrocarbon, and the amount of the multi-walled carbon nanotube produced per 1 g of the catalyst for carbon nanotube synthesis is Y(g), When the contact reaction time between the catalyst for carbon nanotube synthesis and the hydrocarbon is Z (minutes), the catalyst amount and/or the flow rate of hydrocarbons are adjusted so that Y/Z (g/minute) satisfies 1.5 ≤ Y/Z ≤ 2.7. Adjust.

In an embodiment of the method for manufacturing the multi-walled carbon nanotube, the hydrocarbon is ethylene.

The dispersion liquid of the present invention contains the multi-walled carbon nanotubes of the present invention and a dispersant.

The resin composition of the present invention contains the multi-walled carbon nanotube of the present invention and a resin.

In addition, the coating film of this invention is formed of the said resin composition of this invention.

A resin composition excellent in jet-black properties is provided using the multi-walled carbon nanotube of the present invention. Therefore, it is possible to use the multi-walled carbon nanotube and the method for producing the multi-walled carbon nanotube of the present invention in various applications requiring high jet blackness.

1 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes when 300 multi-walled carbon nanotubes are randomly observed using the transmission electron microscope obtained in Example 1;
Fig. 2 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes when 300 multi-walled carbon nanotubes are randomly observed using the transmission electron microscope obtained in Example 4;
3 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes when 300 multi-walled carbon nanotubes are randomly observed using the transmission electron microscope obtained in Comparative Example 1;
4 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes when 300 multi-walled carbon nanotubes are randomly observed using the transmission electron microscope obtained in Comparative Example 2;
5 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes when 300 multi-walled carbon nanotubes are randomly observed using the transmission electron microscope obtained in Comparative Example 3;
6 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes when 300 multi-walled carbon nanotubes are randomly observed using the transmission electron microscope obtained in Comparative Example 4;
7 is a graph showing the relationship between the outer diameter and number of multi-walled carbon nanotubes obtained in Example 12 when 300 carbon nanotubes are randomly observed using a transmission electron microscope;
8 is a graph showing the relationship between the outer diameter and number of multiwalled carbon nanotubes obtained in Example 13 when 300 carbon nanotubes were randomly observed using a transmission electron microscope.

Hereinafter, the multi-walled carbon nanotube dispersion liquid of the present invention, the resin composition, and the coating film thereof will be described in detail.

(1) Multi-walled carbon nanotube (A)

The multi-walled carbon nanotube (A) has a shape in which planar graphite is wound into a cylindrical shape. The multi-walled carbon nanotube (A) may be a mixture of single-walled carbon nanotubes. A single-walled carbon nanotube has a structure in which one layer of graphite is wound. The multi-walled carbon nanotube (A) has a structure in which two or three or more layers of graphite are wound. Moreover, the side wall of the multi-walled carbon nanotube (A) may not have a graphite structure. For example, a carbon nanotube having a sidewall having an amorphous structure may be used as the multi-walled carbon nanotube (A).

The shape of the multi-walled carbon nanotube (A) is not limited. These shapes include various shapes such as needle shape, cylindrical tube shape, fish bone shape (fish bone or cup stacked), card shape (platelet), and coil shape. In this embodiment, the shape of the multi-walled carbon nanotube (A) is preferably a needle shape or a cylindrical tube shape. The multi-walled carbon nanotube (A) may have a single shape or a combination of two or more shapes.

Further, the form of the multi-walled carbon nanotube (A) includes, for example, graphite whisker, fibrous carbon, graphite fiber, ultrafine carbon tube, carbon tube, carbon fibrils, carbon microtube, and carbon nanofiber, but limited to these doesn't happen The multi-walled carbon nanotube (A) may have such an individual form or a form in which two or more types are combined.

The average outer diameter of the multi-walled carbon nanotube (A) of this embodiment is 10 nm or less, and the standard deviation of the outer diameter is 4 nm or less. When the multi-walled carbon nanotube (A) has such a specific outer diameter, a resin composition with high jet black properties is obtained.

The average outer diameter of the multi-walled carbon nanotubes (A) is particularly preferably 3 to 10 nm, more preferably 4 to 10 nm, still more preferably 4 to 8 nm, from the viewpoints of easiness of dispersion and color.

The standard deviation of the outer diameter of the multi-walled carbon nanotubes (A) may be 4 nm or less, and from the viewpoint of easiness of dispersion and color, among them, it is preferably 3 nm or less, and more preferably 2.5 nm or less. Moreover, 0.7 nm or more is preferable and, as for the standard deviation of an outer diameter, 1.4 nm or more is more preferable.

Further, when the average outer diameter of carbon nanotubes is X [nm] and the standard deviation of the outer diameter of carbon nanotubes is σ [nm], since a resin composition with high jet black properties is obtained, X ± σ [nm] is 5.0 nm ≤ It is preferable that X±σ ≤ 14.0 nm.

Further, from the viewpoint of obtaining a resin composition with high jet-black properties, X±2σ [nm] is preferably 2.0 nm ≤ X±2σ ≤ 17.0 nm, more preferably 2.5 nm ≤ X±2σ ≤ 15.5 nm, 3.0 nm ≤ It is more preferable that X±2σ ≤ 12.0 nm.

The outer diameter and average outer diameter of the multi-walled carbon nanotube (A) can be obtained as follows. First, the multi-walled carbon nanotube (A) is observed with a transmission electron microscope and an image is captured. Next, arbitrary 300 multi-walled carbon nanotubes (A) are selected from the observation photograph, and the outer diameter of each is measured. Next, the average outer diameter (nm) of the multi-walled carbon nanotubes (A) is calculated as the number average of the outer diameters.

The fiber length of the multi-walled carbon nanotube (A) of the present embodiment is preferably 0.1 to 150 µm, more preferably 1 to 10 µm, from the viewpoint of easiness of dispersion and color.

The carbon purity of the multi-walled carbon nanotube (A) is expressed by the content (% by mass) of carbon atoms in the multi-walled carbon nanotube (A). The carbon purity is preferably 85 mass % or more, more preferably 90 mass % or more, still more preferably 95 mass % or more with respect to 100 weight % of the multi-walled carbon nanotube (A).

In this embodiment, the multi-walled carbon nanotubes (A) are generally present as secondary particles. The shape of the secondary particles may be, for example, a state in which multi-walled carbon nanotubes (A), which are general primary particles, are complicatedly entangled. An aggregate of the multi-walled carbon nanotubes (A) having a linear shape may be used. The secondary particles, which are aggregates of the linear multi-walled carbon nanotubes (A), tend to unravel compared to those that are entangled. In addition, since the linear ones have better dispersibility compared to the entangled ones, they can be preferably used as the multi-walled carbon nanotubes (A).

The multi-walled carbon nanotube (A) may be a surface-treated carbon nanotube. Further, the multi-walled carbon nanotube (A) may be a carbon nanotube derivative to which a functional group represented by a carboxyl group is imparted. Moreover, the multi-walled carbon nanotube (A) in which an organic compound, a metal atom, or a substance typified by fullerene is contained can also be used.

The multi-walled carbon nanotube (A) of the present embodiment is preferably a carbon nanotube having a relatively small number of layers. In particular, when powder X-ray diffraction analysis is performed, a peak exists at a diffraction angle of 2θ = 25 ° ± 2 °, and the half width of the peak is preferably 3 ° or more and 5.5 ° or less, and more preferably 5 ° or more and 5.5 ° or less . By using such a multi-walled carbon nanotube (A) having a relatively small number of layers, a coating film having high jet-black properties can be obtained because the brightness is low and the specular gloss is improved.

The layer structure of the multi-walled carbon nanotube (A) can be analyzed by powder X-ray diffraction analysis by the following method.

The half width of the multi-walled carbon nanotube (A) can be obtained as follows. First, the multi-walled carbon nanotube (A) is filled in a predetermined sample holder so that the surface thereof is flat, put into a powder X-ray diffraction analyzer, and measured by changing the irradiation angle of the X-ray source from 5° to 80°. As the X-ray source, for example, CuKα ray is used. The step width is 0.010° and the measurement time is 1.0 sec. The multi-walled carbon nanotube (A) can be evaluated by reading the diffraction angle 2θ at which the peak appears. In graphite, a peak is usually detected at 2θ around 26°, and it is known that this is a peak due to interlayer diffraction. Since the multi-walled carbon nanotube (A) also has a graphite structure, a peak due to graphite interlayer diffraction is detected in this vicinity. However, since carbon nanotubes have a cylindrical structure, their values are different from those of graphite. A peak appears at the position of the value 2θ of 25°±2°, so that it can be determined that the composition includes a multilayer structure rather than a single layer. Since the peak appearing at this position is a peak due to interlayer diffraction of the multilayer structure, the number of layers of the multi-walled carbon nanotube (A) can be determined. Since the single-walled carbon nanotube has only one layer, a peak does not appear at the position of 25°±2° with the single-walled carbon nanotube alone. However, even in single-walled carbon nanotubes, when not 100% single-walled carbon nanotubes but multi-walled carbon nanotubes, etc. are mixed, a peak may appear at a position where 2θ is 25°±2.

In the multi-walled carbon nanotube (A), a peak appears at a position where 2θ is 25°±2°. Moreover, the layer composition can also be analyzed from the half-width of the peak of 25°±2° detected by powder X-ray diffraction analysis. That is, it is thought that the number of layers of a multi-walled carbon nanotube (A) is large, so that the half width width of this peak is small. Conversely, it is thought that the number of carbon nanotube layers is small, so that the half-width of this peak is large.

In the multi-walled carbon nanotube (A) of the present embodiment, G/D when the maximum peak intensity in the Raman spectrum is G in the range of 1560 to 1600 cm ^-1 and the maximum peak intensity in the range of 1310 to 1350 cm ^-1 is D It is preferable that a ratio is 4.9-0.3, It is more preferable that it is 2.0-0.3, It is more preferable that it is 1.0-0.5. The multi-walled carbon nanotube (A) G/D ratio is determined by Raman spectroscopy.

There are several laser wavelengths used in Raman spectroscopy, but 532 nm and 632 nm are used here. In the Raman spectrum, the Raman shift seen near 1590 cm ^-1 is called a graphite-derived G band, and the Raman shift seen near 1350 cm ^-1 is called a D band derived from defects between amorphous carbon and graphite. The higher the G/D ratio is, the higher the graphitization degree is.

In addition, the Raman spectrum 150 to 350 cm ^-1 is called RBM (radial bridging mode), and the peak observed in this region has the following correlation with the outer diameter of the carbon nanotube, and it is possible to predict the outer diameter of the carbon nanotube . Assuming that the outer diameter of the carbon nanotube is d (nm) and the Raman shift is ν (cm- ^-1 ), d=248/ν is established. Considering this, the peaks observed at 140cm ^-1 , 160cm ^-1 , 180cm ^-1 , 210cm ^-1 , 270cm ^-1 , 320cm ^-1 in Raman spectroscopy with a wavelength of 532 nm are, that is, 1.77 nm, 1.55 nm, 1.38 nm. , suggesting that carbon nanotubes having outer diameters of 1.18 nm, 0.92 nm, and 0.78 nm exist.

Since the wavenumber of Raman spectroscopy may fluctuate depending on the measurement conditions, the wavenumber prescribed here shall be defined as the wavenumber ±10cm ^-1 .

[Method for producing multi-walled carbon nanotube (A)]

In the present embodiment, the multi-walled carbon nanotube (A) is not particularly limited as long as it is a manufacturing method in which the average outer diameter of the multi-walled carbon nanotube is 10 nm or less and the standard deviation of the outer diameter is 4 nm or less, and the carbon nanotube manufactured by any method it's good too The multi-walled carbon nanotube (A) can be generally produced by a laser peeling method, an arc discharge method, a thermal CVD method, a plasma CVD method, and a combustion method. Further, for example, the multi-walled carbon nanotube (A) can be produced by contacting a carbon source with a catalyst at 500 to 1000°C in an atmosphere having an oxygen concentration of 1% by volume or less.

In this embodiment, as the method for manufacturing the multi-walled carbon nanotube (A), a method including the following steps is preferable.

(1) A step of obtaining a catalyst for synthesizing carbon nanotubes by mixing and/or pulverizing cobalt and a metal salt containing magnesium and calcining them

(2) a step of obtaining multi-walled carbon nanotubes by bringing the catalyst for synthesizing carbon nanotubes into contact with a carbon source containing at least one selected from hydrocarbons and alcohols under heating

As the source gas serving as the carbon source, any conventionally known source gas may be used. For example, hydrocarbon, carbon monoxide, alcohol, etc. are mentioned, It can use individually by 1 type or in combination of 2 or more type. In this embodiment, the carbon source preferably includes at least one selected from hydrocarbons and alcohols, and more preferably includes hydrocarbons. Examples of the hydrocarbon include methane, propane, butane, and acetylene, and among them, ethylene is preferable.

When ethylene is used as the carbon source, it is preferable to prepare the multi-walled carbon nanotube (A) by reacting the carbon source with the catalyst in contact with the catalyst at 600 to 800° C. in an atmosphere having an oxygen concentration of 1% by volume or less, and at 650 to 750° C. It is more preferable to produce the multi-walled carbon nanotubes (A) by subjecting the carbon source to a catalytic reaction with a catalyst.

The amount of hydrocarbon may be appropriately changed depending on the size of the reaction vessel and the amount of catalyst in the reaction vessel, but when the amount of carbon nanotubes produced per 1 g of catalyst is Y (g) and the catalyst-hydrocarbon contact reaction time Z (minutes) , it is preferable to adjust the amount of catalyst and/or the flow rate of hydrocarbon so that Y/Z (g/min) satisfies 1.5 ? Y/Z ? 2.7.

If necessary, after activating the catalyst in a reducing gas atmosphere, it is preferable to catalytically react the raw material gas with the catalyst in an atmosphere having an oxygen concentration of 1% by volume or less. Moreover, you may make the raw material gas catalytically react with a reducing gas. The atmosphere with an oxygen concentration of 1% by volume or less is not particularly limited, but an inert gas atmosphere typified by an inert gas such as argon gas and nitrogen gas is preferable. The reducing gas used for catalyst activation may use hydrogen or ammonia, but is not limited thereto. The reducing gas is particularly preferably hydrogen.

As the catalyst, various conventionally known metals may be used. Specifically, it is a metal oxide obtained by mixing and/or pulverizing an active ingredient represented by cobalt, nickel or iron, and a catalyst carrier represented by magnesium, aluminum or silicon. In particular, a metal oxide obtained by mixing and/or pulverizing a cobalt catalyst as an active ingredient and a metal containing magnesium as a support is preferable. By using cobalt as an active ingredient and magnesium as a catalyst carrier, it is easy to obtain multi-walled carbon nanotubes having an average outer diameter of 10 nm or less and a standard deviation of the outer diameter of 4 nm or less.

As an active ingredient, specifically, ammonium iron(III) citrate, iron(II) ammonium sulfate hexahydrate, iron(III) chloride hexahydrate, iron(II) chloride tetrahydrate, iron(III) citrate n-hydrate, iron(III) nitrate ) nonhydrate, iron(II) oxalate dihydrate, iron(III) oxide, cobalt hydroxide, cobalt(II) acetate tetrahydrate, basic cobalt(II) carbonate, cobalt(II) chloride, cobalt(II) chloride hexahydrate, cobalt nitrate (II) hexahydrate, cobalt(II) oxide, cobalt(II, III) oxide, cobalt(II) stearate, cobalt(II) sulfate heptahydrate, cobalt(II) sulfide, cobalt(II) acetate, nickel(II) sulfate ) ammonium hexahydrate, nickel (II) acetate tetrahydrate, nickel (II) chloride, nickel (II) chloride hexahydrate, nickel (II) hydroxide, nickel (II) nitrate hexahydrate, nickel (II) oxide, nickel sulfate ( II) hexahydrate, and the like. Particularly preferred are cobalt hydroxide, cobalt(II) acetate tetrahydrate, iron(III) citrate n-hydrate, and iron(III) nitrate nonhydrate. Two or more of these active ingredients may be combined.

The catalyst carrier contains magnesium, exhibits adsorption and catalytic activity, and is preferably capable of supporting a catalyst metal on the surface of the catalyst carrier, and may be an organic material or an inorganic material.

As magnesium of the catalyst carrier, a conventionally known magnesium compound may be used. For example, magnesium, magnesium chloride, magnesium hydroxide, magnesium oxide, magnesium sulfate, magnesium acetate tetrahydrate, basic magnesium carbonate, magnesium chloride hexahydrate. In particular, it is preferable to use magnesium acetate tetrahydrate, magnesium hydroxide, and magnesium oxide.

Examples of the catalyst support include, in addition to magnesium, silicon oxide, aluminum, basic aluminum acetate, aluminum bromide, aluminum chloride, aluminum hydroxide, aluminum lactate, aluminum oxide, zeolite, titanium oxide, zirconium, calcium oxide, and the like. desirable. By combining two components having different melting points, it is possible to prevent fusion between particles during catalyst preparation. For example, catalytic activity can be improved by bonding with organic substances such as magnesium acetate and aluminum acetate and inorganic substances such as silicon oxide, aluminum oxide, zeolite, titanium oxide, zirconium, and magnesium oxide. In particular, when magnesium acetate tetrahydrate is used for the catalyst carrier, it is preferable to combine silicon oxide, zeolite, and aluminum oxide. Particularly preferred are silicon oxide and zeolite.

Silicon oxide, zeolite, and aluminum oxide used in the catalyst carrier, for example, AEROSIL (registered trademark) 50, AEROSIL (registered trademark) 130, AEROSIL (registered trademark) 200, AEROSIL (registered trademark) of Nippon Aerosil Corporation of Evonik Group Trademark) 300 AEROSIL (registered trademark) 380, AEROXIDE (registered trademark) AluC, AEROXIDE (registered trademark) TiO2P25, Nippon Kikina's alumina C10W, C20, C40, C50, C500, Tosoh's beta zeolite 940HOA, 980HOA, Mordenite It is preferable to use zeolite 640HOA, 690HOA, Y-type zeolite 320HOA, 331HSA, 350HUA, 360HUA, 385HUA, 390HA. Especially, AEROSIL (trademark) is preferable.

The content of silica and aluminum in the catalyst carrier is preferably 1 to 50 mol%, more preferably 1 to 25 mol%, when the magnesium content is 100 mol%.

The bulk density of silica and aluminum in the catalyst carrier is preferably 0.04 to 0.5 g/ml. In the case of using silica, it is more preferably 0.04 to 0.1 g/ml.

The bulk density is the bulk density before a volume reducing treatment such as degassing and granulation, and is a value measured according to JIS-K-5101.

The BET specific surface area of silica and alumina of the catalyst carrier is preferably 50 to 1000 m 2 /g, more preferably 150 to 350 m 2 /g.

The catalyst carrier preferably includes a crude catalyst having a function of enhancing the catalytic action of the catalyst. For example, it is preferable that manganese, molybdenum, tungsten are included. Particularly preferred are manganese or molybdenum. By including them in the catalyst support, catalyst activity and catalyst life can be improved. These co-catalysts may be single or may contain two or more.

The content of the crude catalyst in the catalyst carrier is preferably 5 to 100 mol%, more preferably 5 to 30 mol%, when the magnesium content is 100 mol%.

As the manganese salt or molybdenum salt used for the catalyst carrier, various conventionally known salts can be used. For example, manganese(II) acetate tetrahydrate, manganese(II) carbonate n-hydrate, manganese(II) chloride tetrahydrate, manganese(II) nitrate hexahydrate, manganese(IV) oxide, manganese(II) sulfate pentahydrate, Ammonium Molybdate, Molybdenum, Potassium Molybdate, Hexammonium Chylmolybdate Tetrahydrate, Molybdenum Chloride (V), Molybdenum Oxide (VI), Molybdenum Sulfide (IV), Ammonium Tungstate Parapentahydrate, Potassium Tungstate, Tungsten (VI) ) sodium dihydrate, tungsten, tungsten (VI) oxide, and the like. In particular, manganese(II) acetate tetrahydrate, manganese(II) carbonate n-hydrate, ammonium molybdate, and molybdenum (VI) oxide are preferable.

The materials of the catalyst carrier are preferably mixed uniformly. Mixing may be wet or dry, but dry mixing is preferable when an insoluble salt is used in water. In the case of mixing the raw materials in a wet manner, it is preferable to dry them in the range of 100 to 200° C. and then mix them.

It is preferable that the catalyst carrier contains little moisture. When the catalyst carrier is 100 mass %, it is preferable that the moisture content is 5 mass % or less, and it is preferable that it is 3 mass % or less. The moisture content in the catalyst carrier can be measured using, for example, a heat-drying moisture meter (MS-70, A-End Day Co., Ltd.).

The particle diameter of the catalyst carrier is preferably small. Specifically, the particle size distribution preferably has a D50 (μm) of 1.0 to 10.0 μm, more preferably 1.0 to 5.0 μm. Moreover, it is preferable that D90 (micrometer) is 5.0-70.0 micrometers, and it is more preferable that it is 5.0-20.0 micrometers.

The particle size distributions D50 (μm) and D90 (μm) of the catalyst carrier can be obtained as follows. First, the particle size distribution of the catalyst carrier is measured by a laser diffraction dry particle size distribution measuring device. The particle size at the time of the cumulative distribution of 50 vol% of the measurement result can be calculated as D50 (μm), and the particle size at the time of the cumulative distribution of 90 vol% can be calculated as D90 (μm).

As a method of reducing the particle size of the catalyst carrier, various conventionally known methods can be used. Among them, it is preferable to use a pulverizer capable of applying compressive force, impact force, shear force and friction force to the catalyst carrier.

A grinder is a device for refining a sample by applying a force such as compression, impact, shear or friction to the sample. Devices for refining include mortar, pin mill, hammer mill, pulperizer, atomizer, jet mill, cutter mill, ball mill, bead mill, colloid mill, conical mill, disc mill, edge mill, wonder crusher, vibrating A grinder such as a mill or an ultrasonic homogenizer may be used. Preferred are attritors, pin mills, hammer mills, jet mills, cutter mills, ball mills, bead mills, wonder crushers, and vibration mills, which are prone to complexing, mechanical alloying, and amorphization of catalyst particles. Particularly preferred are atomizers, ball mills, bead mills and vibrating mills using beads as grinding media.

As a grinding medium, various conventionally known beads may be used. For example, they are steel beads, zirconia beads, alumina beads, and glass beads. Among them, it is preferable to use steel beads with large specific gravity and zirconia beads with high hardness.

As the diameter of the beads, various conventionally known beads can be used, but it is preferable to use beads having a diameter of 1 to 10 mm from the viewpoint of workability. It is more preferable to use beads of 2 to 5 mm.

The catalyst is preferably prepared by uniformly mixing and/or pulverizing the active component, the catalyst carrier, and the crude catalyst component. As the mixing and/or grinding method, various conventionally known methods may be used. Mixing and/or grinding devices include those described above.

The catalyst is preferably an oxide by mixing and pulverizing the active component, the catalyst carrier, and the metal salt to be the crude catalyst component, followed by calcination in air.

Although the calcination temperature changes with the oxygen concentration at the time of calcination, it is preferable that it is 300-900 degreeC in oxygen presence, and it is more preferable that it is 300-750 degreeC.

After the catalyst is calcined, it is preferable that the pulverized particle size D50 of the solid material be 50 µm or less, more preferably 20 µm or less. A homogeneous catalyst is obtained by pulverizing the solid to align the particle size.

(2) Resin composition (B)

The resin composition (B) of the present embodiment contains at least the multi-walled carbon nanotubes (A) and the resin (C). The resin composition of the present embodiment can be suitably used for forming a coating film with high jet-black properties containing the multi-walled carbon nanotube (A) of the present invention.

In order to obtain the resin composition (B) of the present embodiment, it is preferable to disperse the multi-walled carbon nanotubes (A) and the resin (C) in a solvent. The equipment used to perform these operations is not particularly limited. For example, paint conditioner (Red Devil), ball mill, sand mill (Shinmal Enterprises' "Dino Mill"), atomizer, pearl mill (Irich's "DCP mill"), ultrasonic homogenizer (Advanced Digital Sonifer (registered trademark), MODEL 450DA, manufactured by BRANSON), COBOL Mill, Basket Mill, Homo Mixer, Homogenizer (“Clairemix” by M Technic), Wet Jet Mill (“Genas PY” by Genas, “Genas PY” by Nanomizer) "Nanomizer") Hoover Mahler, a three roll mill, and an extruder are mentioned.

Moreover, in order to obtain a resin composition (B), a high-speed stirrer can also be used. Examples of the high-speed stirrer include, but are not limited to, Homodisper (manufactured by PRIMIX), Fill Mix (manufactured by PRIMIX), Dissolver (manufactured by Inoue, Ltd.), and Hyper HS (manufactured by Ashizawa Finetech).

Resin (C)

The resin (C) is selected from natural resins and synthetic resins. Independent resin may be sufficient as resin (C). As the resin (C), two or more kinds of resins may be selected from natural resins and synthetic resins. Two or more types of resin can be used in combination.

Examples of the natural resin include, but are not limited to, natural rubber, gelatin, rosin, shellac, polysaccharides, and gilsonite. In addition, synthetic resins include phenol resins, alkyd resins, petroleum resins, vinyl resins, olefin resins, synthetic rubbers, polyester resins, polyamide resins, acrylic resins, styrene resins, epoxy resins, melamine resins, polyurethane resins, and amino resins. , amide resin, imide resin, fluorine resin, vinylidene fluoride resin, vinyl chloride resin, ABS resin, polycarbonate, silicone resin, nitrocellulose, rosin-modified phenolic resin, and rosin-modified polyamide resin, but are not limited thereto. .

Among these resins, it is preferable to include at least one of an acrylic resin and a polyester resin from the viewpoint of light resistance. In addition, at this time, it is preferable to include at least one of an acrylic resin and a polyester resin also in the base paint.

The water-soluble resin used for the resin composition (B) of the present embodiment is preferably a water-soluble resin having an acid value of 20 to 70 mgKOH/g and a hydroxyl value of 20 to 160 mgKOH/g. Specifically, a polyester resin, an acrylic resin, and a polyurethane resin are particularly preferably used as the water-soluble resin.

Polyester resin is a resin using polyhydric alcohol and polybasic acid as raw materials. The acid value of the polyester resin is 20 to 70 mgKOH/g, preferably 25 to 60 mgKOH/g, particularly preferably 30 to 55 mgKOH/g. The hydroxyl value of the polyester resin is 20 to 160 mgKOH/g, preferably 80 to 130 mgKOH/g.

In this example, the acid value refers to the mass (mg) of potassium hydroxide required to neutralize 1 g of resin. In addition, the hydroxyl value refers to the mass (mg) of potassium hydroxide required to react the hydroxyl group of the resin with phthalic anhydride to neutralize the acid required for the reaction and 1 g of the resin.

In addition, in this Example, the measurement of the acid value and hydroxyl value of resin can be implemented by the method of JISK0070.

The water-soluble polyester resin can be easily obtained by a known esterification reaction. Water-soluble polyester resins are resins prepared from polyhydric alcohols and polybasic acids. The raw material may be a compound constituting a general polyester resin. If necessary, oils and fats may be added to the water-soluble polyester resin.

Examples of the polyhydric alcohol include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,6-hexanediol, di ethylene glycol, dipropylene glycol, neopentyl glycol, triethylene glycol, hydrogenated bisphenol A, glycerin, trimethylol ethane, trimethylol propane, pentaerythritol and dipentaerythritol. These polyhydric alcohols may be used independently and may be used in combination of two or more types.

Examples of the polybasic acid include phthalic anhydride, isophthalic acid, terephthalic acid, succinic anhydride, adipic acid, azelaic acid, sebacic acid, maleic anhydride, fumaric acid, itaconic acid and trimellitic anhydride. not limited These polybasic acids may be used alone or in combination of two or more types.

In addition, examples of the oils and fats include, but are not limited to, soybean oil, palm oil, safflower oil, rice bran oil, castor oil, tung oil, linseed oil and tall oil, and fatty acids obtained therefrom.

The acrylic resin is a resin using a vinyl-based monomer as a raw material. The acid value of the acrylic resin is 20 to 70 mgKOH/g, preferably 22 to 50 mgKOH/g, particularly preferably 23 to 40 mgKOH/g. The hydroxyl value of the acrylic resin is 20 to 160 mgKOH/g, preferably 80 to 150 mgKOH/g, a water-soluble resin.

The water-soluble acrylic resin can be easily obtained by a known solution polymerization method or other methods. The water-soluble acrylic resin is a resin prepared from a vinyl-based monomer as a raw material. The material may generally be a compound constituting an acrylic resin. Also, in the above method, an organic peroxide is used as a polymerization initiator.

Examples of the vinyl monomer include ethylenically unsaturated carboxylic acids represented by acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, and crotonic acid; alkyl esters of acrylic acid or methacrylic acid represented by methyl, ethyl, propyl, butyl, isobutyl, t-butyl, 2-ethylhexyl, lauryl, cyclohexyl and stearyl; hydroxyalkyl esters of acrylic acid or methacrylic acid represented by 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, and polyethylene glycol having a molecular weight of 1000 or less; amides of acrylic acid or methacrylic acid; or its alkyl ethers, but is not limited thereto. For example, acrylamide, methacrylamide, N-methylol acrylamide, diacetone acrylamide, diacetone methacrylamide, N-methoxymethyl acrylamide, N-methoxymethyl methacrylamide and N-butoxy methyl acrylamide, but is not limited thereto.

Moreover, the glycidyl (meth)acrylate which has an epoxy group is mentioned. Moreover, monomers containing a tertiary amino group are also mentioned. Examples include, but are not limited to, N,N-dimethyl amino ethyl (meth)acrylate and N,N-diethyl amino ethyl (meth)acrylate. In addition, aromatic monomers represented by styrene, α-methyl styrene, vinyl toluene and vinyl pyridine; acrylonitrile; methacrylonitrile; vinyl acetate; and mono or dialkyl esters of maleic acid or fumaric acid. Organic peroxides include, for example, acyl peroxides (eg benzoyl peroxide), alkyl hydroperoxides (eg t-butyl hydroperoxide and p-methane hydroperoxide) and dialkyl peroxides. oxides (eg, di-t-butyl peroxide), but are not limited thereto.

The polyurethane resin is a resin using polyol and polyisocyanate as raw materials. The acid value of the polyurethane resin is 20 to 70 mgKOH/g, preferably 22 to 50 mgKOH/g, particularly preferably 23 to 35 mgKOH/g. The hydroxyl value of the polyurethane resin is 20 to 160 mgKOH/g, preferably 25 to 50 mgKOH/g.

A water-soluble polyurethane resin can be easily obtained by addition polymerization of a polyol and a polyisocyanate. The raw material may be a polyol and polyisocyanate constituting a general polyurethane resin.

Polyols include, but are not limited to, polyester polyols, polyether polyols, and acrylic polyols. In addition, as polyisocyanate, phenylene diisocyanate, torylene diisocyanate, xylene diisocyanate, bisphenylene diisocyanate, naphthalene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, cyclopentylene diisocyanate, cyclohexylene Diisocyanate, methylcyclohexylene diisocyanate, dicyclohexylmethane diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, propylene diisocyanate, ethylethylene diisocyanate and trimethylhexane diisocyanate , but is not limited thereto.

Water solubility is imparted to water-soluble polyester resins, acrylic resins and polyurethane resins by neutralizing them with a basic substance. In this case, it is preferable to use a basic substance in an amount capable of neutralizing 40 mol% or more of the acidic groups contained in the water-soluble resin. Examples of the basic material include ammonia, dimethylamine, trimethylamine, diethylamine, triethylamine, propylamine, triethanolamine, N-methylethanolamine, N-aminoethylethanolamine, N-methyldiethanolamine , morpholine, mono isopropanol amine, diisopropanol amine, and dimethyl ethanol amine.

The number average molecular weight of the water-soluble resin is not particularly limited. 500-50,000 are preferable, as for a number average molecular weight, 800-25,000 are more preferable, and 1,000-12,000 are especially preferable.

In addition, the resin (C) is classified into a type having curability and a lacquer type. In this embodiment, a curable type resin is preferably used. The resin (C) of the curable type is used together with an amino resin represented by a melamine resin or a crosslinking agent represented by a (block) polyisocyanate compound, an amine-based compound, a polyamide-based compound, and a polyhydric carboxylic acid. After the resin (C) and the crosslinking agent are mixed, the curing reaction proceeds by heating or placing at room temperature. Moreover, it is also possible to use resin of the type which does not have sclerosis|hardenability as resin for coating-film formation, and resin of the type which has sclerosis|hardenability.

The resin composition (B) of the present embodiment may contain at least the multi-walled carbon nanotubes (A) and the resin (C), and may contain another component as necessary.

As other components, a dispersing agent, a solvent, etc. are mentioned, for example.

As the dispersant, a surfactant, a resin type dispersant or an organic pigment derivative can be used. Surfactants are mainly classified into anionic, cationic, nonionic and amphoteric. According to the characteristics required for dispersion of the multi-walled carbon nanotubes (A), a suitable type of dispersing agent can be used in a preferable blending amount. Preferred as the dispersant are resin-type dispersants.

When an anionic surfactant is selected, the type is not particularly limited. Specifically, fatty acid salts, polysulfonic acid salts, polycarboxylic acid salts, alkyl sulfuric acid ester salts, alkyl aryl sulfonic acid salts, alkyl naphthalene sulfonic acid salts, alkyl sulfonates, dialkyl sulfosuccinic acid salts, alkyl phosphate salts, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl aryl ether sulfate, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl phosphoric acid sulfonate, glycerol borate fatty acid ester, and polyoxyethylene glycerin fatty acid ester. Specific examples include sodium dodecylbenzene sulfonate, sodium lauryl sulfate, sodium polyoxyethylene lauryl ether sulfate, polyoxyethylene nonyl phenyl ether sulfate ester salt, and β-naphthalene sulfonic acid formalin condensate sodium salt. However, the present invention is not limited thereto.

In addition, as cationic surfactants, there are alkylamine salts and quaternary ammonium salts. Specifically, stearyl amine acetate, cocoyl trimethyl ammonium chloride, alkyl trimethyl ammonium chloride, dimethyl dioleyl ammonium chloride, methyl oleyl diethanol chloride, tetramethyl ammonium chloride, lauryl pyridinium chloride, lauryl pyridinium bromide, la uryl pyridinium disulfate, cetyl pyridinium bromide, 4-alkyl mercapto pyridine, poly(vinyl pyridine)-dodecyl bromide, and dodecyl benzyl triethyl ammonium chloride. In addition, the amphoteric surfactant may include, but is not limited to, amino carboxylic acid salts.

Also, nonionic surfactants include, but are not limited to, polyoxyethylene alkyl ethers, polyoxyalkylene derivatives, polyoxyethylene phenyl ethers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and alkyl aryl ethers. does not Specific examples include, but are not limited to, polyoxyethylene lauryl ether, sorbitan fatty acid ester, and polyoxyethylene octyl phenyl ether.

The surfactant to be selected is not limited to the sole surfactant. Therefore, it is also possible to use two or more surfactants together. Combinations of anionic surfactants and nonionic surfactants, or combinations of cationic surfactants and nonionic surfactants are possible, for example. It is preferable to make the compounding quantity at that time into a compounding quantity preferable with respect to each surfactant component. The combination is preferably a combination of an anionic surfactant and a nonionic surfactant. The anionic surfactant is preferably a polycarboxylate. The nonionic surfactant is preferably polyoxyethylene phenyl ether.

Moreover, specifically as a resin type dispersing agent, polyurethane; polycarboxylic acid esters of polyacrylates; unsaturated polyamides, polycarboxylic acids, polycarboxylic acids (partial) amine salts, polycarboxylic acid ammonium salts, polycarboxylic acid alkylamine salts, polysiloxanes, long-chain polyaminoamide phosphates and hydroxyl group-containing polycarboxylic acid esters and modified products thereof; oily dispersants of amides or salts thereof formed by reaction of a polymer of lower alkylene imine and free polyester having a carboxyl group; (meth)acrylate-styrene copolymer, (meth)acrylic acid-(meth)acrylic acid ester copolymer, styrene-maleic acid copolymer, polyvinyl alcohol and water-soluble resin or water-soluble high molecular compound represented by polyvinylpyrrolidone; polyester-based resin; modified polyacrylate-based resin; ethylene oxide/propylene oxide addition compounds; And phosphoric acid ester-based resin is used, but is not limited thereto. These may be used alone or in combination of two or more, but is not limited thereto.

Among the dispersants, a resin-type dispersant having an acidic functional group such as polycarboxylic acid is preferable. This is because such a resin-type dispersing agent reduces the viscosity of the dispersion composition with a small addition amount and also increases the spectral transmittance of the dispersion composition. It is preferable to use about 3 to 300 mass % of a resin type dispersing agent with respect to a multi-walled carbon nanotube (A). Moreover, it is more preferable to use about 5-100 mass % from a viewpoint of film-forming property.

Commercially available resin-type dispersants include ANTI-TERRA (registered trademark)-U/U100, ANTI-TERRA (registered trademark)-204, ANTI-TERRA (registered trademark)-250*, DISPERBYK (registered trademark) from Bicchemy Japan. , DISPERBYK (registered trademark)-102, DISPERBYK (registered trademark)-103, DISPERBYK (registered trademark)-106, DISPERBYK (registered trademark)-108, DISPERBYK (registered trademark)-109, DISPERBYK (registered trademark)- 110/111 , DISPERBYK (registered trademark)-118*, DISPERBYK (registered trademark)-140, DISPERBYK (registered trademark)-142, DISPERBYK (registered trademark)-145, DISPERBYK (registered trademark)-161, DISPERBYK (registered trademark)-162/ 163, DISPERBYK (registered trademark)-164, DISPERBYK (registered trademark)-167, DISPERBYK (registered trademark)-168, DISPERBYK (registered trademark)-170/171, DISPERBYK (registered trademark)-174, DISPERBYK (registered trademark)- 180, DISPERBYK (registered trademark)-182, DISPERBYK (registered trademark)-184, DISPERBYK (registered trademark)-185, DISPERBYK (registered trademark)-187, DISPERBYK (registered trademark)-190, DISPERBYK (registered trademark)-191, DISPERBYK (registered trademark)-192, DISPERBYK (registered trademark)-193, DISPERBYK (registered trademark)-194N*, ISPERBYK (registered trademark)-198*, DISPERBYK (registered trademark)-199*, DISPERBYK (registered trademark)-2000 , DISPERBYK (registered trademark)-2001, DISPERBYK (registered trademark)-2008, DISPERBYK (registered trademark)-2009, DISPERBYK (registered trademark)-2010, DISPERBYK (registered trademark)-2012*, DISPERBYK (registered trademark)-2013* , DISPERBYK (registered trademark)-2015, DISPERBYK (registered trademark)-2022*, DISPERBYK (registered trademark)-2025, DISPERBYK (registered trademark)-2050, DISPERBYK (registered trademark) Table)-2096, DISPERBYK (registered trademark)-2150, DISPERBYK (registered trademark)-2152*, DISPERBYK (registered trademark)-2155, DISPERBYK (registered trademark)-2163, DISPERBYK (registered trademark)-2164, DISPERBYK (registered trademark) )-2200*, BYK (registered trademark)-P104/P104S, BYK (registered trademark)-P105, BYK (registered trademark)-9076, BYK (registered trademark)-9077, BYK (registered trademark)-220S, Japanese Lubri Zolsa's SOLSPERSE-3000, 5000, 9000, 11200, 12000, 13240, 13650, 13940, 16000, 17000, 18000, 20000, 21000, 24000GR, 26000, 27000, 28000, 32000, 32500, 32550, 32600, 33000, 34750, 35100, 35200, 36000, 36600, 37500, 38500, 39000, 41000, 41090, 43000, 44000, 46000, 47000, 53095, 55000, 56000, 71000 and 76500, Dispex(R) from BASF UltraPA4550, Dispex(R) UltraPA4560, Dispex (registered trademark) UltraPX4575, Dispex (registered trademark) UltraPX4585, Efka (registered trademark) FA4608, Efka (registered trademark) FA4620, Efka (registered trademark) FA4644, Efka (registered trademark) FA4654, Efka (registered trademark) FA4663 , Efka (registered trademark) FA4665, Efka (registered trademark) FA4666, Efka (registered trademark) FA4672, Efka (registered trademark) FA4673, Efka (registered trademark) PA4400, Efka (registered trademark) PA4401, Efka (registered trademark) PA4403, Efka (registered trademark) PA4450, Efka (registered trademark) PU4063, Efka (registered trademark) PX4300, Efka (registered trademark) PX4310, Efka (registered trademark) PX4320, Efka (registered trademark) PX4330, Efka (registered trademark) PX4340, Efka (registered trademark) PX4700, Efka (registered trademark) PX4701, Efka (registered trademark) PX4731, Efka (registered trademark) PX4732, Efka (registered trademark) PA4560, Efka (registered trademark) PX4575, Efka (registered trademark) PX4585 , Efka (registered trademark) FA4600, Efka (registered trademark) FA4601, Kyoei Sha Chemical Corporation's Floren DOPA-15B, Floren DOPA-15BHFS, Floren DOPA-17HF, Floren DOPA-22, Floren DOPA- 35, Floren G-700, Floren G-820XF, Floren GW-1500, Floren G-100SF, Floren AF-1000, Floren AF-1005, Floren KDG-2400, Floren D-90 and Ajisper PA111, PN411, PB821, PB822, PB824, PB881 manufactured by Ajinomoto Fine Techno, but is not limited thereto.

Examples of the organic pigment derivative include an organic dye derivative having an acidic functional group represented by the following general formula (2), and a triazine derivative having an acidic functional group represented by the following general formula (1).

The symbols in the formulas indicate the following meanings.

_Q1 : An organic dye residue or an anthraquinone residue or a heterocyclic ring which may have a substituent or an aromatic ring which may have a substituent

R ₁ : -OR ₂ , -NH-R ₂ , halogen group, -X ₁ -R ₂ , -X ₂ -Y ₁ -Z ₁ (R ₂ represents a hydrogen atom or an optionally substituted alkyl or alkenyl group .)

X1 : -NH-, -O-, -CONH-, -SO ₂ NH-, -CH ₂ NH-, -CH ₂ NHCOCH ₂ NH- or -X ₃ -Y ₁ -X ₄ - (X ₃ and X ₄ each independently represents -NH- or -O-.)

X ₂ : -CONH-, -SO ₂ NH-, -CH ₂ NH-, -NHCO- or -NHSO ₂ -

Y ₁ : An alkylene group which may have a substituent consisting of 1 to 20 carbon atoms, an alkenylene group which may have a substituent, or an arylene group which may have a substituent

Z ₁ : -SO ₃ M, -COOM (M represents 1 equivalent of a 1-3 valent cation.)

Examples of the organic dye residue of Q ₁ in the general formula (1) include phthalocyanine dyes, azo dyes, quinacridone dyes, dioxazine dyes, anthrapyrimidine dyes, andanthrone dyes, indanthrone dyes, flavans. Pigments or dyes, such as a tron-type pigment|dye and a triphenylmethane-type pigment|dye, are mentioned.

As a heterocyclic or aromatic ring of Q ₁ in the general formula (1), for example, thiophene, furan, pyridine, pyrazole, pyrrole, imidazole, isoindoline, isoindolinone, benzimidazolone, Benzthiazole, benztriazole, indole, quinoline, carbazole, acridine, benzene, naphthalene, anthracene, fluorene, phenanthrene, etc. are mentioned.

General formula (2)

Q ₂ -(-X ₅ -Z ₂ )n

The symbols in the formula indicate the following meanings.

_Q2 : organic pigment residue or anthraquinone residue

X ₅ : direct bond, -NH-, -O-, -CONH-, -SO ₂ NH-, -CH ₂ NH-, -CH ₂ NHCOCH ₂ NH- or -X ₆ -Y ₂ -X ₇ -(X ₆ and X ₇ each independently represents -NH- or -O-, and Y ₂ represents an alkylene group or arylene group which may have a substituent.)

Z ₂ : -SO ₃ M, -COOM (M represents 1 equivalent of 1 to trivalent cation.)

n : an integer from 1 to 4

Examples of the organic dye residue of Q ₂ in the general formula (2) include phthalocyanine dyes, azo dyes, quinacridone dyes, dioxazine dyes, anthrapyrimidine dyes, andanthrone dyes, indanthrone dyes, flavans. and pigments or dyes such as tron-based dyes, perylene-based dyes, perinone-based dyes, thioindigo-based dyes, isoindolinone-based dyes, and triphenylmethane-based dyes.

The resin composition (B) may contain a solvent. As the solvent, both an aqueous solvent and an organic solvent can be used.

The aqueous solvent is water or a solvent containing water. As the solvent including water, an aqueous liquid may be used. Examples of specific water-soluble liquids include, for example, water-soluble compounds represented by acetaldehyde, propylene oxide, acetone, pyridine, methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, acetic acid, propionic acid, acrylic acid, ethylene glycol, glycerin, and the like. of flammable liquids.

Among organic solvents, an organic solvent having a boiling point of 50 to 250°C is easy to use. These organic solvents are excellent in workability during coating and drying properties before and after curing. Specific examples of the solvent include alcohol solvents typified by methanol, ethanol and isopropyl alcohol; ketone solvents typified by acetone, butyl glycol acetate and MEK (methyl ethyl ketone); ester solvents typified by ethyl acetate and butyl acetate; ether-based solvents typified by dibutyl ether, ethylene glycol and monobutyl ether; and an amphoteric aprotic solvent typified by N-methyl-2-pyrrolidone, but is not limited thereto. These solvents may be used individually or in mixture of 2 or more types.

Furthermore, aromatic hydrocarbon solvents represented by toluene, xylene, Solvesso #100 (manufactured by Tonen General) and Solvesso #150 (manufactured by Tonen General); aliphatic hydrocarbon solvents represented by hexane, heptane, octane and decane; Alternatively, an amide-based solvent typified by cellosolve acetate, ethyl cellosolve, and butyl cellosolve may be used. These solvents can also be used individually or in mixture of 2 or more types.

Moreover, an additive can be suitably mix|blended with the said solvent as needed in the range which does not impair the objective of this embodiment. Additives include, but are not limited to, pigments, wetting penetrants, lid inhibitors, ultraviolet absorbers, antioxidants, crosslinking agents, preservatives, mold inhibitors, viscosity modifiers, pH modifiers, leveling agents and defoaming agents.

(3) Coating film (D)

The coating film of the present embodiment is a coating film formed of the resin composition (B) of the present embodiment, and includes the multi-walled carbon nanotubes (A) and the resin (C). Although the base material (E) is provided under this coating film (D), the base material can be removed after the coating film (D) is produced.

The coating film (D) of this embodiment has high jet-blackness by containing the said multi-walled carbon nanotube (A).

The coating film (D) of this embodiment can be formed by apply|coating the said resin composition (B) by a general method. Techniques include, inter alia, casting, spin coating, dip coating, bar coating, spraying, blade coating, slit die coating, gravure coating, reverse coating, screen printing, mold application, printing transfer and wet coating methods including inkjet, However, the present invention is not limited thereto. A coating film may be formed by coating the resin composition (B) on the substrate (E) by the above technique.

The addition rate of the multi-walled carbon nanotube (A) in the coating film (D) may be appropriately selected according to the application. The addition rate is preferably in the range of 0.1 to 30% by mass, more preferably 1 to 25% by mass, and still more preferably 2 to 15% by mass. In particular, when the addition rate is within such a range, a coating film excellent in jet black properties can be obtained.

Carbon black other than the multi-walled carbon nanotubes (A) can be added to the coating film (D) as long as it does not impair the object of the present invention. Specific examples of carbon black include ketjen black, acetylene black, furnace black and channel black. Carbon black is the partial oxidation of hydrocarbons typified by naphtha in the presence of hydrogen and oxygen, and may be a by-product when producing a synthesis gas containing hydrogen and carbon monoxide. Further, carbon black may be obtained by oxidizing or reducing such by-products. The above does not limit the carbon black according to the present invention. These carbon blacks may be used individually, or two or more types may be used together. In addition, from the viewpoint of improving blackness, carbon black having an average particle diameter of 20 nm or less and DBP oil absorption of 80 mL/100 g or less is preferably used. In addition, in this example, DBP oil absorption indicates the amount (mL) of dibutyl phthalate (DBP) that can be included per 100 g of carbon black. DBP oil absorption is a measure to quantify the structure of carbon black. The structure is a complex agglomeration form due to chemical or physical bonding between carbon black particles.

The average particle diameter of carbon black can be calculated|required similarly to the outer diameter of a multi-walled carbon nanotube (A). Specifically, while observing carbon black with a transmission electron microscope, an image is captured. Next, random 300 carbon blacks are selected from the observation photograph and the particle size of each is measured. Next, the average particle diameter (nm) of carbon black is computed from the number average of particle diameters.

1-25 mass parts is preferable with respect to 100 mass parts of multi-walled carbon nanotubes (A), as for the usage-amount of carbon black, 1-10 mass parts is more preferable, 1-5 mass parts is still more preferable.

It is preferable that it is 5 micrometers or more, and, as for the thickness of the coating film (D), it is more preferable that it is 10 micrometers or more.

As for the coating film (D), a clear layer may further be formed on the coating film (D). By forming a clear layer, the coating film (D) provided with glossiness, light resistance, and jet-blackness is obtained.

It is preferable that it is 5.7 or less, and, as for the brightness L which the coating film (D) shows, it is more preferable that it is 5.5 or less, It is still more preferable that it is 5.3 or less, It is especially preferable that it is 5.2 or less. This brightness L is obtained by measuring using a colorimeter. The measurement is performed on the surface of the coating film (D) from the side where the coating film (D) is formed. As a color difference meter, NIPPONDENSHOKU's Spectro Color Meter SE6000 may be used.

It is preferable that it is 60 or more, as for the 60 degree mirror glossiness of the coating film (D), it is more preferable that it is 80 or more, It is still more preferable that it is 85 or more. As the gloss meter, gloss meter GM-26D (manufactured by Murakami Color Research Institute) may be used.

Substrate (E)

The base material (E) used in order to form the coating film (D) of this embodiment is not specifically limited. As a material of the base material (E), metals represented by iron, aluminum and copper or alloys thereof; inorganic materials represented by glass, cement and concrete; resins typified by polyethylene resins, polypropylene resins, ethylene-vinyl acetate copolymer resins, polyamide resins, acrylic resins, vinylidene chloride resins, polycarbonate resins, polyurethane resins and epoxy resins; plastic materials represented by various FRPs; wood; and natural materials or synthetic materials typified by fiber materials (including paper and cloth), but are not limited thereto.

Among the above materials, metals represented by iron, aluminum and copper or alloys thereof are preferable. Moreover, resin containing the pigment represented by carbon black and carbon nanotube is also preferable.

The shape of the base material (E) may be a plate shape, a film shape, a sheet shape, or a molded body shape. The production of the molded body includes, for example, an injection molding method typified by an insert injection molding method, an in-mold molding method, an overmolding method, a two-color injection molding method, a core back injection molding method, and a sandwich injection molding method; extrusion molding method typified by T-die lamination molding method, multi-layer inflation molding method, co-extrusion molding method and extrusion coating method; and a multilayer blow molding method, a multilayer calender molding method, a multilayer press molding method, a slush molding method, and a melt molding method can be used.

(4) Multi-walled carbon nanotube (CNT) dispersion (F)

Although the manufacturing method of the resin composition (B) of this embodiment mentioned above is not specifically limited, As one method, the method of preparing a CNT dispersion liquid (F) and adding resin to the said CNT dispersion liquid (F) is mentioned. The CNT dispersion liquid (F) contains at least the multi-walled carbon nanotubes (A) and a dispersing agent, and generally further contains a solvent. In addition, the dispersion liquid (F) does not contain resin (C).

In order to obtain the CNT dispersion liquid (F), it is preferable to carry out dispersion treatment of the multi-walled carbon nanotubes (A) in a solvent. The equipment used to perform these operations is not particularly limited. For example, paint conditioner (manufactured by Red Devil), ball mill, sand mill (“Dynomyl” of Shinmal Enterprises Co., Ltd.), atomizer, pearl mill (“DCP mill” of Eirich Co., Ltd.), ultrasonic homogenizer (Advanced Digital Sonifer) (registered trademark), MODEL 450DA, manufactured by BRANSON), COBOL mill, basket mill, homomixer, homogenizer (“Claire Mix” by M Technic), wet jet mill (“Genas PY” by Genas, “Nano” by Nanomizer) Meizer"), Hoover Mahler, three roll mills, and extruders, but are not limited thereto.

As the dispersant included in the CNT dispersion (F), a surfactant, a resin-type dispersant, or an organic pigment derivative may be used. Surfactants are mainly classified into anionic, cationic, nonionic and amphoteric. Preferred as the dispersant are resin-type dispersants. Specific examples of the dispersant are the same as those described for the resin composition (B), and thus a description thereof will be omitted.

In addition, since the solvent contained in the CNT dispersion (F) is the same as that described for the resin composition (B), the description here is omitted.

It turned out that the resin composition (B) and the coating film (D) using the above multi-walled carbon nanotubes (A) had good jet black properties.

The reason for the good jet-blackness is believed to be that the multi-walled carbon nanotubes (A) with a small outer diameter have stronger interactions between the carbon nanotubes compared to general carbon nanotubes, and form and hold bundles firmly. Therefore, the specific surface area becomes small, and the wettability with respect to a solvent and a dispersing agent improves. Moreover, the orientation of carbon nanotubes is easy to maintain also in the resin composition (B) and coating film (D) after dispersion, and the effect of confinement of light is large.

[Example]

Next, the present invention will be described in more detail by way of examples. The present invention is not limited to the following examples unless the gist thereof is exceeded. In Examples, "part" means "part by mass" and "%" means "mass %", respectively, unless otherwise specified. In addition, "carbon nanotube" can be abbreviated as "CNT" and "carbon black" as "CB".

<Method of measuring physical properties>

The physical properties of the CNT or CNT coating film used in each of the Examples and Comparative Examples below were measured by the following method.

<Raman spectroscopy analysis of CNTs>

CNTs were installed in a Raman microscope (manufactured by XploRA Co., Ltd. Horiba), and measurement was performed using a laser wavelength of 532 nm. Measurement conditions were: a measurement time of 60 seconds, the number of integrations twice, a photosensitive filter 10%, a magnification of the objective lens 20 times, the number of lines of a diffraction grating 1200/min, a confocal hole 500, and a slit width of 100 µm. CNTs for measurement were taken on a glass slide and flattened using a spatula. In the spectrum of the obtained peaks, the maximum peak intensity in the range of 1560 to 1600 cm ^-1 was G, the maximum peak intensity in the range of 1310 to 1350 cm ^-1 was D, and the G/D ratio was defined as the G/D ratio of CNTs.

<CNT powder X-ray diffraction analysis>

CNTs were installed in an X-ray diffraction apparatus (manufactured by Rigaku, Ltd., Ultima2100), and analyzed by operating from 1.5° to 80°. The X-ray source is CuKα. The step width was 0.01° and the measurement time was 1.0 sec. At this time, the plots appearing at the obtained diffraction angle 2θ=25°±2° were each 11-point simple moving average, and the half-width of the peak was taken as the half-width of CNTs.

<Preparation of CNT dispersion>

In a 450 mL SM sample bottle (manufactured by Sansho Corporation), 0.2 g of carbon nanotubes and 0.2 g of polyvinyl pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) as a resin-type dispersant were weighed, added to 200 mL of isopropyl alcohol, and an ultrasonic homogenizer (Advanced Digital Sonifer (registered trademark), MODEL 450DA, manufactured by BRANSON) was used for dispersion treatment under ice cooling at 50% amplitude for 5 minutes to prepare a CNT dispersion.

<Transmission electron microscopy analysis of CNTs>

The CNT dispersion was diluted appropriately, several microliters were dripped at the collodion membrane, and after drying at room temperature, it directly observed using the transmission electron microscope (H-7650, Hitachi Co., Ltd. product). For observation, several photos containing 10 or more CNTs in the field of view were taken at a magnification of 50,000 times, and the outer diameters of 300 randomly extracted CNTs were measured, and the average value was taken as the average outer diameter of CNTs (nm). The standard deviation was calculated from the measured 300 CNT outer diameter as a population.

Also for reference, graphs showing the relationship between the outer diameter and number of the multi-walled carbon nanotubes of Examples 1, 4, 12 to 13, and Comparative Examples 1 to 4 described later in FIGS. 1 to 8 are shown.

<Measuring method of brightness (L) of CNT coating film>

About the CNT coating film, the brightness (L) was measured using the color-difference meter (Spectro Color Meter SE6000 by NIPONDENSHOKU) from the surface to which the CNT resin composition was coated.

<Measurement of gloss of CNT coating film>

About the CNT coating film, the 60 degree mirror gloss was measured by glossmeter GM-26D (made by Murakami Color Research Institute) according to JIS Z8741 from the side on which the CNT resin composition was coated.

[First Example Group]

<Example of Preparation of Catalyst for CNT Synthesis>

The catalyst for CNT synthesis used in each of the Examples and Comparative Examples below was prepared by the following method.

Catalyst for CNT synthesis (A)

60 parts of cobalt hydroxide, 138 parts of magnesium acetate tetrahydrate, and 16.2 parts of manganese acetate are each put in a heat-resistant container, dried at a temperature of 170±5° C. using an electric oven for 1 hour to evaporate moisture, and then crushed (Wonder Crusher WC- 3, using Osaka Chemical Co., Ltd.), the SPEED dial was adjusted to 3, and pulverized for 1 minute. Thereafter, each of the pulverized powders was adjusted to 2 using a pulverizer (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and the SPPED dial was adjusted to 2 and mixed for 30 seconds to prepare a CNT synthesis catalyst precursor (A). Then, the CNT synthesis catalyst precursor (A) was transferred to a heat-resistant container, heated for 30 minutes in an air atmosphere of 450±5°C using a muffle furnace (FO510, Yamato Chemical Co., Ltd.), and then pulverized with a mortar to CNT A catalyst for synthesis (A) was obtained.

Catalyst for CNT synthesis (B)

60 parts of cobalt hydroxide, 138 parts of magnesium acetate tetrahydrate, and 8.1 parts of manganese carbonate were each put in a heat-resistant container, dried at a temperature of 170±5° C. using an electric oven for 1 hour to evaporate moisture, and then crushed (Wonder Crusher WC- 3, using Osaka Chemical Co., Ltd.), the SPEED dial was adjusted to 3, and pulverized for 1 minute. Thereafter, each of the pulverized powders was adjusted to 2 using a pulverizer (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and the SPEED dial was adjusted to 2 and mixed for 30 seconds to prepare a CNT synthesis catalyst precursor (B). Then, the CNT synthesis catalyst precursor (B) is transferred to a heat-resistant container and heated for 30 minutes in an air atmosphere of 450±5°C using a muffle furnace (FO510 Yamato Chemical Co., Ltd.), and then pulverized with a mortar to synthesize CNTs. A catalyst (B) was obtained.

Catalyst for CNT synthesis (C)

60 parts of cobalt hydroxide, 138 parts of magnesium acetate tetrahydrate, 16.2 parts of manganese carbonate, and 4.0 parts of zeolite (HSZ-940HOA, manufactured by Tosoh Corporation) were placed in a heat-resistant container, respectively, and 1 at a temperature of 170±5° C. using an electric oven. After drying for time to evaporate moisture, the SPEED dial was adjusted to 3 using a grinder (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.), and grinding was performed for 1 minute. Then, each of the pulverized powders was adjusted to 2 using a pulverizer (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and the SPEED dial was adjusted to 2 and mixed for 30 seconds to prepare a CNT synthesis catalyst precursor (C). Then, the CNT synthesis catalyst precursor (C) is transferred to a heat-resistant container and heated for 30 minutes in an air atmosphere of 450±5°C using a muffle furnace (FO510 Yamato Chemical Co., Ltd.), and then pulverized with a mortar to synthesize CNTs. A catalyst (C) was obtained.

Catalyst for CNT synthesis (D)

60 parts of cobalt hydroxide, 138 parts of magnesium acetate tetrahydrate, 16.2 parts of manganese carbonate, and 4.0 parts of Aerosil (AEROSIL (registered trademark) 200 Nippon Aerosil Co., Ltd.) were placed in a heat-resistant container, respectively, and heated in an electric oven at 170±5° C. After drying at a temperature of 1 hour to evaporate moisture, the SPEED dial was adjusted to 3 using a grinder (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and grinded for 1 minute. Then, each of the pulverized powders was adjusted to 2 using a pulverizer (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and the SPEED dial was adjusted to 2 and mixed for 30 seconds to prepare a CNT synthesis catalyst precursor (D). Then, the CNT synthesis catalyst precursor (D) is transferred to a heat-resistant container and heated for 30 minutes in an air atmosphere of 450±5°C using a muffle furnace (FO510 Yamato Chemical Co., Ltd.), and then pulverized with a mortar to synthesize CNTs. A catalyst (D) was obtained.

Catalyst for CNT synthesis (E)

60 parts of cobalt hydroxide, 166 parts of magnesium acetate tetrahydrate, 16.2 parts of manganese carbonate, and 4.0 parts of Aerosil (AEROSIL (registered trademark) 200 Nippon Aerosil Co., Ltd.) were placed in a heat-resistant container, respectively, and heated in an electric oven at 170±5° C. After drying at a temperature of 1 hour to evaporate moisture, the SPEED dial was adjusted to 3 using a grinder (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and grinded for 1 minute. Then, each of the pulverized powders was adjusted to 2 using a pulverizer (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.) and the SPEED dial was adjusted to 2 and mixed for 30 seconds to prepare a CNT synthesis catalyst precursor (E). Then, the CNT synthesis catalyst precursor (E) is transferred to a heat-resistant container and heated for 30 minutes in an air atmosphere of 450±5°C using a muffle furnace (FO510 Yamato Chemical Co., Ltd.), and then pulverized with a mortar to synthesize CNTs. A catalyst (E) was obtained.

Catalyst for CNT synthesis (F)

60 parts of cobalt hydroxide, 138 parts of magnesium acetate tetrahydrate, and 16.2 parts of manganese acetate are placed in one heat-resistant container, dried at a temperature of 170±5° C. using an electric oven for 1 hour to evaporate moisture, and then passed through 80 mesh. The particle size was adjusted to prepare a CNT synthesis catalyst precursor (F). Then, transfer the CNT synthesis catalyst precursor (F) to a heat-resistant container and use a muffle furnace (FO510 Yamato Chemical Co., Ltd.) to heat it in an air atmosphere of 450±5° C. for 30 minutes, then grind it with a mortar for CNT synthesis A catalyst (F) was obtained.

(Example 1) Preparation of CNT (A)

A heat-resistant dish made of quartz glass in which 2.0 g of the catalyst for CNT synthesis (A) was dispersed was installed in the center of a horizontal reaction tube with a volume of 10 L that can be pressurized and that can be heated by an external heater. The nitrogen gas was evacuated while injecting, and the air in the reaction tube was replaced with nitrogen gas so that the atmosphere in the horizontal reaction tube had an oxygen concentration of 1% by volume or less. Then, it was heated with an external heater until the center temperature of the horizontal reaction tube reached 680 °C. After reaching 680° C., propane gas as a carbon source was introduced into the reaction tube at a flow rate of 2 L per minute, and the reaction was carried out in contact with each other for 1 hour. After completion of the reaction, CNT (A) was obtained by replacing the gas in the reaction tube with nitrogen gas and cooling the temperature of the reaction tube to 100° C. or less.

(Example 2-5) CNT (B) to (E) fabrication

CNTs (B) to (E) were obtained in the same manner as in Example 1, except that catalysts for CNT synthesis (B) to (E) were used instead of the catalyst for CNT synthesis (A).

(Comparative Example 1) Preparation of CNT (F)

CNT (F) was obtained in the same manner as in Example 1, except that the CNT synthesis catalyst (F) was used instead of the CNT synthesis catalyst (A).

(Comparative Example 2) CNT (G) fabrication

A heat-resistant dish made of quartz glass in which 2.0 g of the catalyst for CNT synthesis (F) was dispersed was installed in the center of a horizontal reaction tube with a volume of 10 L that can be pressurized and that can be heated by an external heater. The nitrogen gas was evacuated while injecting, and the air in the reaction tube was replaced with nitrogen gas so that the atmosphere in the horizontal reaction tube had an oxygen concentration of 1% by volume or less. Then, it was heated with an external heater until the center temperature of the horizontal reaction tube reached 680 °C. After reaching 680° C., ethylene gas as a carbon source was introduced into the reaction tube at a flow rate of 2 L per minute, and the reaction was carried out in contact with the reaction tube for 1 hour. After completion of the reaction, the gas in the reaction tube was replaced with nitrogen gas and the temperature of the reaction tube was cooled to 100° C. or less to obtain CNT (G).

(Comparative Example 3-4) CNT (H) to (I)

Multi-walled carbon nanotubes (NC7000, manufactured by Nanosil) were used as CNT (H), and multi-walled carbon nanotubes (Flotube9000, manufactured by Cnano) were used as CNT (I).

Table 1 shows the evaluation results of CNTs (A) to (I). The average outer diameter of CNTs was denoted by X, and the standard deviation of the outer diameters of CNTs was denoted by σ.

[Table 1]

(Example 6) Preparation of CNT resin composition and coating film

CNT (A) 5.6 g, as a dispersant resin-type dispersant (DISPERBYK (registered trademark)-111, manufactured by Big Chemie, 100% non-volatile matter) 11.2 g, Solvesso 150 as a solvent (made by Tonen General Petroleum Corporation) 48.8 g, toluene 73.5 g, xylene 73.5 g, and butyl acetate 48.8 g were added to a plastic container (Dethcup 1L Tokyo Glass Machinery Co., Ltd.), and stirred for 5 minutes at a rotation speed of 1500 rpm using a high-speed stirrer (T.K.HOMODISPER MODEL2.5, Flymix Co., Ltd.). Thereafter, using a high-speed stirrer (T.K.HOMOMIXER MARKII MODEL2.5, manufactured by Flymix Co., Ltd.), dispersion treatment was carried out at a rotation speed of 5000 rpm for 5 minutes to obtain a crude CNT dispersion (A). 100 parts of this CNT crude dispersion (A) and 175 parts of zirconia beads (beads diameter of 1.0 mmφ) were placed in a 200 mL SM sample bottle (manufactured by Sansho, Inc.) and dispersed for 3 hours using Red Devil's paint conditioner. A dispersion (A) was obtained. Thereafter, 92.6 parts of an acrylic resin (Acrylic Dick 47-712 manufactured by DIC, 50% non-volatile content) was added and stirred for 5 minutes at a rotation speed of 1500 rpm using a high-speed stirrer (T.K.HOMODISPER MODEL2.5, manufactured by Flymix Co., Ltd.). Next, 19.3 parts of melamine resin (DIC's Super Becamine L-117-60, non-volatile content 60%) was added to the CNT dispersion (A), and dispersion treatment was performed for 30 minutes using Red Devil's paint conditioner, and the CNT resin composition (A) was obtained. Next, using a PET (polyethylene terephthalate) film (Lumira 100, T60, manufactured by Toray Corporation) as a substrate, the CNT resin composition (A) was spray-coated on one side so that the film thickness after drying was set to 20 µm. Spray painting was performed using an air spray gun (W-61-2G manufactured by Anestoiwata). After coating, the PET film was left at room temperature for 30 minutes, and then dried at 140±5° C. for 30 minutes to prepare a CNT coating film (A).

(Examples 7 to 10) (Comparative Examples 5-8)

CNT resin compositions (B) to (I), CNT dispersions (B) to (I), CNT coating films (B) to (I) in the same manner as in Example 6 except that CNTs listed in Table 2 were changed. got

[Table 2]

Table 3 shows the evaluation results of the CNT coating films produced in Examples 6 to 10 and Comparative Examples 5 to 8. The jet-blackness evaluation criteria were as follows. When the lightness (L) of the coating film is 5.5 or less and the 60° specular gloss is + + (excellent) of 80 or more, the brightness (L) of the coating film is 5.7 or less and the 60° mirror gloss is 80 or more + (good), the brightness of the coating film (L) exceeded 5.7, or 60 degree mirror gloss made less than 80 - (poor).

[Table 3]

(Comparative Example 9)

In the same manner as in Example 6, except that carbon black (COLOR Black FW-200) manufactured by Degussa was used instead of CNT, the CB resin composition (A), CB dispersion (A), and CB coating film (A) were got it

Table 4 shows the evaluation results of the CB coating film produced in Comparative Example 9. The jet-blackness evaluation criteria were as follows. If the lightness (L) of the coating film is 5.5 or less and the 60° mirror gloss is + + (good) of 80 or more, the brightness (L) of the coating film is 5.7 or less and the 60° mirror gloss is 80 or more + (good), the brightness of the coating film (L) exceeded 5.7, or 60 degree mirror gloss made less than 80 - (poor).

[Table 4]

According to the results of the first example group, the coating films of Examples 6 to 10 using the multi-walled carbon nanotubes of Examples 1 to 5 having an average outer diameter of 10 nm or less and a standard deviation of the outer diameter of 4 nm or less were multi-walled carbon nanotubes with a large outer diameter. It was found that the coating film of Comparative Examples 5 to 8 and Comparative Example 9 using carbon nano black had a particularly low brightness and excellent jet blackness.

[Second Example Group]

<Example of Preparation of Catalyst for CNT Synthesis>

The CNT synthesis catalyst carrier, cobalt composition, and catalyst for CNT synthesis used in each of the Examples and Comparative Examples below were prepared by the following method.

<Preparation of CNT synthesis catalyst support>

1000 parts of magnesium acetate tetrahydrate was placed in a heat-resistant container, dried at a temperature of 170±5 ° C. using an electric oven for 6 hours, and then using a grinder (Sample Mill KIIW-I type manufactured by Dalton Co., Ltd.), a 1 mm screen was mounted, , and pulverized to obtain a magnesium acetate dry pulverized product. Magnesium acetate dry pulverized product 45.8 parts, manganese carbonate 8.1 parts, silicon oxide (SiO ₂ ) Nippon Aerosil Co., Ltd.: 1.0 parts of AEROSIL (registered trademark) 200), 200 parts of steel beads (beads diameter 2.0 mmφ) were placed in an SM sample bottle (manufactured by Sansho, Inc.), and ground and mixed for 30 minutes using Red Devil's paint conditioner. was carried out Thereafter, the pulverized mixed powder and the steel beads (beads diameter of 2.0 mmφ) were separated using a stainless steel sieve to obtain a CNT synthesis catalyst carrier.

<Preparation of catalyst for CNT synthesis>

30 parts of cobalt (II) hydroxide was placed in a heat-resistant container and dried at a temperature of 170±5° C. for 2 hours to obtain a cobalt composition containing CoHO ₂ . After that, 54.9 parts of the catalyst support for CNT synthesis and 29 parts of the cobalt composition are put into a grinder (Wonder Crusher WC-3, Osaka Chemical Co., Ltd.), a standard lid is attached, the SPEED dial is adjusted to 2, and the CNTs are pulverized and mixed for 30 seconds. A synthetic catalyst precursor was obtained. The CNT synthesis catalyst precursor was transferred to a heat-resistant container and calcined in an air atmosphere at 450±5° C. for 30 minutes using a muffle furnace (FO510 Yamato Chemical Co., Ltd.), and then pulverized in a mortar to obtain a CNT synthesis catalyst.

(Example 11) Preparation of CNT (J)

A heat-resistant dish made of quartz glass in which 1 g of the catalyst for CNT synthesis was sprayed was installed in the center of a horizontal reaction tube with a volume of 10 L that can be pressurized and heated by an external heater. It was exhausted while injecting nitrogen gas, and the air in the reaction tube was replaced with nitrogen gas and heated until the atmospheric temperature in the horizontal reaction tube reached 710°C. After reaching 710° C., ethylene gas as a hydrocarbon was introduced into the reaction tube at a flow rate of 2 L per minute, and the reaction was carried out in contact with the reaction tube for 7 minutes. After completion of the reaction, CNT (J) was obtained by replacing the gas in the reaction tube with nitrogen gas and cooling the temperature of the reaction tube to 100° C. or less.

(Examples 12 to 16)

CNTs (K) to (O) were obtained in the same manner as in Example 11, except that the catalyst amount, temperature, and reaction time listed in Table 5 were changed.

[Table 5]

(Examples 17 to 19)

CNTs (Q) to (S) were obtained in the same manner as in Example 11 except for changing the temperature and reaction time shown in Table 6.

[Table 6]

(Examples 20 to 21)

CNTs (T) and (U) were obtained in the same manner as in Example 11 except that the catalyst amount, temperature, reaction time, and hydrocarbon listed in Table 7 were changed.

[Table 7]

Table 8 shows the evaluation results of the CNTs prepared in Examples 11 to 21.

[Table 8]

(Example 22) Preparation of CNT resin composition and coating film

CNT (K) 5.6 g, as a dispersant resin-type dispersant (DISPERBYK (registered trademark)-111, manufactured by Big Chemie, 100% non-volatile matter) 11.2 g, Solvesso 150 as a solvent (manufactured by Tonen General Petroleum Corporation) 48.8 g, toluene 73.5 g, 73.5 g of xylene, and 48.8 g of butyl acetate were added to a plastic container (Death Cup 1L Tokyo Glass Machinery Co., Ltd.) and stirred for 5 minutes at a rotation speed of 1500 rpm using a high-speed stirrer (T.K.HOMODISPER MODEL2.5, Flymix Co., Ltd.). Thereafter, using a high-speed stirrer (T.K.HOMOMIXER MARKII MODEL2.5, manufactured by Flymix Co., Ltd.), dispersion treatment was carried out at a rotation speed of 5000 rpm for 5 minutes to obtain a crude CNT dispersion (K). 100 parts of this CNT crude dispersion (K) and 175 parts of zirconia beads (beads diameter of 1.0 mmφ) were placed in a 200 mL SM sample bottle (manufactured by Sansho, Inc.), and dispersed for 3 hours using Red Devil's paint conditioner. A dispersion A was obtained. Thereafter, 92.6 parts of an acrylic resin (Acrylic Dick 47-712 by DIC, 50% non-volatile content) was added and stirred for 5 minutes at a rotation speed of 1500 rpm using a high-speed stirrer (T.K.HOMODISPER MODEL2.5, manufactured by Flymix Co., Ltd.). Then, 19.3 parts of melamine resin (DIC's Super Becamine L-117-60, 60% non-volatile content) was added to the CNT dispersion (K) and dispersed for 30 minutes using Red Devil's paint conditioner, and the CNT resin composition ( K) was obtained. Next, using a PET (polyethylene terephthalate) film (Lumira 100, T60, manufactured by Toray Corporation) as a substrate, the CNT resin composition (K) was dried and spray-coated to a thickness of 20 μm on one side. Spray painting was performed using an air spray gun (W-61-2G, manufactured by Anestoiwata). After the PET film after painting was left at room temperature for 30 minutes, it was dried at 140±5° C. for 30 minutes to prepare a CNT coating film (K).

(Examples 23 to 32)

CNT resin compositions (L) to (U), CNT dispersions (L) to (U), CNT coating films (L) to (U) in the same manner as in Example 22 except that CNTs listed in Table 9 were changed. got

[Table 9]

Table 10 shows the evaluation results of the CNT coating films produced in Examples 22 to 32. Regarding jet blackness evaluation, the lightness (L) of the coating film is 5.2 or less, the 60° specular gloss is 80 or more, ++++ (water), the lightness (L) of the coating film is 5.3 or less, and the 60° mirror gloss is 80 or more +++ (right), the brightness (L) of the coating film is 5.5 or less, 60° mirror gloss is 80 or more ++ (positive), the brightness (L) of the coating film is 5.7 or less, and the 60° mirror gloss is 80 or more + (a), the lightness (L) of the coating film exceeded 5.7, or 60 degree mirror gloss made less than 80 - (poor).

[Table 10]

In the results of the second example group, the average outer diameter is 10 nm or less and the standard deviation of the outer diameter is 4 nm or less, and the half-width of the peak is 5° to 5.5 at the diffraction angle 2θ = 25°±2° of powder X-ray diffraction analysis It was found that the coating films of Examples 22 to 27 using the multi-walled carbon nanotubes of Examples 11 to 16 were particularly excellent in jet blackness.

Although the present invention has been described with reference to the above embodiments, the present invention is not limited thereto. Various changes can be made to the configuration and details of the present invention that those skilled in the art can understand within the scope of the invention.

This application claims priority on the basis of Patent Application 2017-49759 filed on March 15, 2017 and Patent Application Application 2017-243686 filed on December 20, 2017, the entire disclosure of which is incorporated herein by reference.

Claims (12)

A multi-walled carbon nanotube characterized by satisfying the following requirements (1), (2), (3) and (4):
(1) The average outer diameter of the multi-walled carbon nanotubes is 10 nm or less
(2) The standard deviation of the outer diameter of the multi-walled carbon nanotube is 4 nm or less
(3) In the Raman spectrum, when the maximum peak intensity within the range of 1560 to 1600 cm ^-1 is G and the maximum peak intensity within the range of 1310 to 1350 cm ^-1 is D, the G/D ratio should be 2.0 or less
(4) In powder X-ray diffraction analysis, a peak exists at a diffraction angle of 2θ = 25°±2°, and the half-width of the peak is 3° or more and 5° or less, or more than 5° and 5.5° or less.
delete delete According to claim 1,
A multi-walled carbon nanotube characterized in that X±2σ satisfies 2.5 nm ≤ X±2σ ≤ 15.5 nm when the average outer diameter of the multi-walled carbon nanotube is X and the standard deviation of the multi-walled carbon nanotube outer diameter is σ.
delete According to claim 1,
In the Raman spectrum, when the maximum peak intensity in the range of 1560 to 1600 cm ^-1 is G and the maximum peak intensity in the range of 1310 to 1350 cm ^-1 is D, the G/D ratio is 1.0 or less. carbon nanotubes.
A method for producing a multi-walled carbon nanotube according to claim 1, comprising the following steps:
(1) an active ingredient containing at least one selected from cobalt, nickel, and iron, and a catalyst carrier comprising at least one selected from magnesium, aluminum and silicon, pin mill, hammer mill, pulperizer, atomizer A process of obtaining a catalyst by calcining after mixing and pulverizing using a lighter, jet mill, cutter mill, ball mill, bead mill, colloid mill, conical mill, disk mill, edge mill, wonder crusher, vibration mill, or ultrasonic homogenizer
(2) a step of obtaining multi-walled carbon nanotubes by bringing the catalyst into contact with a carbon source containing at least one selected from hydrocarbons and alcohols under heating
8. The method of claim 7,
In the step (2), when the carbon source contains hydrocarbons, the amount of multi-walled carbon nanotubes produced per 1 g of the catalyst is Y (g), and the contact reaction time between the catalyst and the hydrocarbon is Z (minutes), A method for producing multi-walled carbon nanotubes, wherein the amount of catalyst and/or the flow rate of hydrocarbons are adjusted so that Y/Z (g/min) satisfies 1.5 ≤ Y/Z ≤ 2.7.
9. The method of claim 8,
A method for producing a multi-walled carbon nanotube wherein the hydrocarbon is ethylene.
A dispersion containing the multi-walled carbon nanotubes according to claim 1 and a dispersing agent.
A resin composition comprising the multi-walled carbon nanotube according to claim 1 and a resin.
The coating film formed from the resin composition of Claim 11.

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