JP2016060875A - Pigment and composition comprising the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pigment that is easily available and can be produced relatively simply and a composition comprising the same.SOLUTION: A pigment according to the present invention is obtained by crushing petroleum coke. Preferably, a pigment according to the present invention has an average particle diameter of 10 μm or less. A composition according to the present invention comprises at least one material selected from the group consisting of a solvent and a resin, and the pigment according to the present invention.SELECTED DRAWING: None

Description

  The present invention relates to a pigment and a composition containing the same.

  Carbon black, which is a carbon-based material, is used as a black pigment for paints and inks.

Here, for example, Patent Document 1 discloses a technique using carbon black as an ink pigment.
Specifically, this Patent Document 1 discloses a writing instrument comprising at least a carbon black having a specific surface area of 21 to 110 [m ² / g] according to the BET method, polyvinyl butyral, an alcohol solvent and / or a glycol ether solvent. Oil-based pigment inks are described.

Moreover, the technique which uses pitch coke as a compounding agent for ink is described in patent document 2, for example.
Specifically, this Patent Document 2 describes a recording material characterized by containing carbon powder surface-treated with fluorine gas.

Japanese Patent Laid-Open No. 63-245481 Japanese Patent Laid-Open No. 6-80923

  However, since Patent Document 1 does not describe a specific manufacturing method for carbon black, it is understood that carbon black used in the technique described in Patent Document 1 is a general one. Carbon black is generally thermally decomposed by continuously spraying a coal-based or petroleum-based heavy oil or ethylene bottom, which is a residual oil during ethylene production, in a furnace in a high-temperature atmosphere of 1400 ° C or higher, The reaction is controlled while spraying water to control the particle size and the like, and the obtained powder is granulated.

  As described above, general carbon black is a carbon-based material manufactured through complicated processes. In addition, creosote oil, the main raw material for carbon black, is a by-product of coal coke for the production of pig iron, but it is expected that it will be difficult to secure that raw material as future production of pig iron decreases. ing.

  On the other hand, Patent Document 2 describes a recording material containing carbon powder surface-treated with fluorine gas. Examples of the carbon powder include graphite, pitch coke, and carbon black. The pitch coke is not described in detail, and it is not only carbon black that is specifically disclosed in the examples, but also a fluorination treatment is necessary. It is difficult to say that pigments that can be easily manufactured are described.

  This invention is made | formed in view of the said condition, and makes it a subject to provide the pigment which can be obtained easily, and can be manufactured comparatively easily, and a composition containing this.

As a result of diligent research and development to solve the above problems, the present inventor has found that the above problems can be solved by the following, and has completed the present invention. The present invention has the following configuration.
(1) A pigment obtained by pulverizing petroleum coke.
(2) The pigment as described in (1) above, wherein the average particle size is 10 μm or less.
(3) The pigment according to (1) or (2), wherein the petroleum coke has a sulfur content in a dry state of 5 to 12% by mass.
(4) The above-mentioned petroleum coke is a dried product obtained by drying coke collected by pyrolyzing crude oil distillation residue oil or vacuum distillation residue oil at room temperature to 1500 ° C. The pigment according to any one of (1) to (3).
(5) A composition comprising at least one material selected from the group consisting of a solvent and a resin, and the pigment according to any one of (1) to (4).
(6) The composition according to (5), which is a paint or ink.

  According to the present invention, it is possible to provide a pigment that can be easily obtained and can be produced relatively easily and a composition containing the pigment.

It is a figure which shows the particle size distribution measurement result of the pulverized coke obtained in Example 1. The horizontal axis indicates the particle diameter (μm), the left vertical axis indicates the frequency (%), and the right vertical axis indicates the accumulated amount (%). 2 is a SEM photograph of finely pulverized coke obtained in Example 1. (A) is 1000 times magnification, (b) is 5000 times magnification, and (c) is 20000 times magnification. The lower right memory in (a) indicates 10 μm, and the lower right memories in (b) and (c) indicate 1 μm. This is a print obtained in Example 2 (ink A). It is the printing obtained in Example 3 (ink B). It is the printing obtained in Example 4 (ink C). It is the printing obtained in Example 5 (ink D). This is a print obtained in Comparative Example 1 (ink X). This is a print obtained in Example 6 (ink E).

  Hereinafter, the form (embodiment) for implementing the pigment of this invention and the composition containing this is demonstrated in detail.

[Pigment]
First, an embodiment of the pigment according to the present invention will be described.
The pigment according to this embodiment is obtained by pulverizing petroleum coke. The pigment is a powder used for coloring, and is insoluble in water or oil.

(Petroleum coke)
The petroleum coke that is the raw material of the pigment according to the present embodiment is coke that is obtained by pyrolyzing a pyrolysis raw material oil produced in the petroleum refining process with a pyrolysis device, and is obtained at room temperature (for example, about 25 ° C.). ) To 1500 ° C. When petroleum coke is dried at room temperature to 1500 ° C., volatile components can be removed.

  Here, as the pyrolysis raw material oil to be pyrolyzed, the atmospheric distillation residue oil after the crude oil is subjected to atmospheric distillation, the vacuum distillation residue oil after the atmospheric distillation residue oil is distilled under reduced pressure, or the atmospheric distillation Examples include mixed oils of residual oil and vacuum distillation residue oil, and mixed oils of one or more of atmospheric distillation residue oil and vacuum distillation residue oil with other hydrocarbon oils (1).

The atmospheric distillation residue oil related to the pyrolysis raw material oil is not particularly limited as long as it is a residue obtained after atmospheric distillation of the crude oil and separation of the evaporation fraction.
Moreover, the vacuum distillation residue oil which concerns on a pyrolysis raw material oil should just be a residue part after carrying out vacuum distillation of the atmospheric distillation residue oil, and isolate | separating an evaporation fraction, and there is no restriction | limiting in particular.
Further, the pyrolysis feedstock oil may be a mixed oil of atmospheric distillation residue oil and vacuum distillation residue oil, and when the pyrolysis feedstock oil is a mixture oil of atmospheric distillation residue oil and vacuum distillation residue oil, The mixing ratio of the atmospheric distillation residue oil and the vacuum distillation residue oil is not particularly limited and can be adjusted as appropriate.

  The crude oil used as the distillation raw material for atmospheric distillation residue oil is not particularly limited. Examples of crude oils that can be used in the present invention include, for example, Arabian heavy, Arabian medium, Arabian light, Arabian extra light, Kuwait, Basra, Oman, Marvan, Mubarras blend, Zakum, Upper Zakum, Qatarland, Qatar Marine, Umshaif, Siri, Kafuji, Espo and so on. In the present invention, any one of these may be used, or a combination of two or more may be used.

  The pyrolysis raw material oil is a mixed oil of at least one of atmospheric distillation residue oil and vacuum distillation residue oil and other hydrocarbon oil (1), that is, atmospheric distillation residue oil and other hydrocarbon oil. Mixed oil of (1), mixed oil of vacuum distillation residue oil and other hydrocarbon oil (1), or mixed oil of atmospheric distillation residue oil, vacuum distillation residue oil and other hydrocarbon oil (1) It may be. When the pyrolysis raw material oil is a mixed oil of at least one of atmospheric distillation residue oil and vacuum distillation residue oil and other hydrocarbon oil (1), the other hydrocarbon oil (1) is the present invention. For example, slurry oil of fluid catalytic cracking treatment, ethylene cracker residue oil, or the like can be used.

Examples of the conditions for performing the pyrolysis include a pyrolysis temperature, a pressure (gauge pressure), an atmosphere, and the like.
For example, the thermal decomposition temperature is preferably 480 to 530 ° C, more preferably 490 to 510 ° C, and particularly preferably 495 to 505 ° C.
For example, the pressure (gauge pressure) during the pyrolysis treatment is preferably 0.01 to 0.6 MPaG, and more preferably 0.05 to 0.4 MPaG.
The atmosphere for the pyrolysis treatment is preferably steam.
In addition, when excessive foaming is recognized during a thermal decomposition process, an antifoamer can also be thrown in. As the antifoaming agent, for example, a silicon-based antifoaming agent or the like may be used.

  Petroleum coke includes granular particles generally called shot coke and large porous blocks generally called sponge coke. The petroleum coke used as a raw material in the pigment according to the present embodiment may be shot coke or sponge coke, a mixture thereof, or a pulverized product thereof. .

(Crushing process)
As described above, the pigment according to this embodiment can be obtained by pulverizing petroleum coke. Petroleum coke pulverization can be performed by appropriately selecting a general solid material pulverization method. For example, a wet or dry pulverizer can be used. Specific examples of the pulverization treatment of petroleum coke include pulverization using a water jet and pulverization using a mixer or a mill. The pulverization treatment can be appropriately selected and used from these considering the target particle size. In addition, it cannot be overemphasized that the grinding | pulverization process of the petroleum-type coke employ | adopted when obtaining the pigment which concerns on this embodiment is not limited to these. Moreover, the conditions for the grinding treatment are not limited to specific ones. In other words, the pulverization treatment may be performed under any conditions as long as petroleum coke is pulverized and a pigment having an average particle size and particle size distribution described below can be obtained.

(Average pigment particle size and particle size distribution)
The average particle size of the pigment according to this embodiment obtained by pulverizing petroleum coke is preferably 10 μm or less, for example. When the average particle diameter of the pigment is 10 μm or less, a uniform coating film or printing is formed in coating or printing. The average particle diameter of the pigment is, for example, preferably 5 μm or less, more preferably 3 μm or less, and particularly preferably 2 μm or less. The fine pigment having an average particle diameter of 2 μm or less (hereinafter, the pigment is particularly referred to as “fine pigment”) includes, for example, a dry jet mill using air as a supply fluid, and a pigment pulverized by the jet mill. Can be obtained by using a classifying rotor for classifying. That is, the above-mentioned fine pigment can be obtained by pulverizing petroleum coke with a jet mill, classifying the pulverized pigment with a classification rotor, and collecting particles of 2 μm or less.
The average particle diameter of the pigment can be measured by, for example, a laser diffraction / scattering particle size distribution measuring apparatus based on JIS Z 8825.

In addition, the particle size distribution of the pigment is preferably less than 30% by volume, more preferably less than 20% by volume, for example, a product exceeding 10 μm. In other words, the particle size distribution of the pigment is preferably 70% by volume or more, more preferably 80% by volume or more for a product of 10 μm or less. When the particle size distribution of the pigment is more than 10 μm and less than 30% by volume (that is, 10 μm or less is 70% by volume or more), a uniform coating or printing is formed in coating or printing.
In addition, the particle size distribution of a pigment can be calculated from the result measured by the laser diffraction scattering type particle size distribution measuring apparatus based on JISZ8825, for example.

(Sulfur content in the dry state of petroleum coke: 5 to 12% by mass)
In the pigment according to this embodiment, the sulfur content in the dry state of petroleum coke as a raw material is preferably 5 to 12% by mass, and more preferably 6 to 10% by mass. When the sulfur content in the dry state of petroleum coke is in the range of 5 to 12% by mass, the affinity between the pigment according to this embodiment and the substrate (for example, solvent or resin) is improved by sulfur. It is thought that the dispersibility goes up. Therefore, by blending the pigment according to this embodiment with a solvent or a resin, a uniform coating film or printing can be easily formed in application or printing of the composition.
In addition, control of the sulfur content of petroleum coke can be performed by adjusting the sulfur content in the pyrolysis feedstock to be pyrolyzed. In particular, for example, when an atmospheric distillation residue oil is used as a pyrolysis raw material oil, it can be carried out by appropriately selecting a crude oil type as the distillation raw material.

  As described above, the petroleum coke as the raw material can be obtained by the thermal decomposition treatment of the pyrolysis raw material oil and the subsequent sampling, but the petroleum coke collected in this way has a water content of 1 to 12 masses. About% is contained. If the mass of the water-containing petroleum-based coke is used as the reference for calculating the sulfur content, the calculated value of the sulfur content in the petroleum-based coke varies depending on the water-containing state of the petroleum-based coke. Therefore, in calculating the sulfur content in the petroleum coke, the moisture-containing petroleum coke is dried at 200 ° C. ± 10 ° C. for 4 hours (according to JIS M 8811), and the mass of the resulting dried petroleum coke is obtained. And the sulfur content in the petroleum coke may be calculated based on the mass of the dried petroleum coke. That is, the sulfur content in the dry state of petroleum coke is the mass of sulfur in the petroleum coke relative to the mass of petroleum coke in the dry state. The sulfur content in petroleum coke can be measured according to JIS M 8819.

(Use)
The pigment according to the present embodiment described above can be used as a constituent material of the composition together with at least one material selected from the group consisting of a solvent and a resin described later, for example. The composition will be described later.

  Examples of the pigment according to the present invention include various printings such as letterpress ink, offset ink, gravure ink, screen ink, flexographic ink, ink for writing instruments (for example, ink for water-based ballpoint pen and ink for oil-based ballpoint pen), and ink for inkjet printing. It can be used as a pigment for ink or as a pigment for paint.

(effect)
As described above, since the pigment according to the present embodiment can be obtained simply by pulverizing petroleum coke, it is not necessary to go through complicated steps like carbon black, and it is relatively easy to manufacture. Can do. Moreover, since the pigment which concerns on this embodiment can be obtained only by grind | pulverizing petroleum-type coke, raw material ensuring is easy. Furthermore, since the pigment according to this embodiment does not require surface treatment with fluorine gas, it can be produced relatively easily. Needless to say, the pigment according to this embodiment may be surface-treated with fluorine gas. If it does in this way, it is possible to acquire effects, such as improving the dispersion stability as a pigment.

  Further, the pigment according to this embodiment can be blended with at least one material selected from the group consisting of a solvent and a resin. In particular, when the average particle size and / or particle size distribution of the pigment according to this embodiment is controlled as described above, it can be uniformly dispersed in the solvent. As a result, a solvent or a resin (that is, a composition described later) in which the pigment according to the present embodiment is blended can form a uniform coating film or printing in application or printing.

[Composition]
Next, an embodiment of the composition according to the present invention will be described.
The composition according to this embodiment includes at least one material selected from the group consisting of a solvent and a resin, and the pigment according to one embodiment described above. In addition, since it has already demonstrated about the pigment, the description is abbreviate | omitted below.

(paint)
The above-described composition is, for example, a paint.
Examples of the paint in the present invention include oil-based paints, water-based paints, water-based paints, high solid paints, and powder paints.

The oil-based paint refers to a paint containing the above-described pigment, a resin, and an organic solvent as a main liquid component.
The water-based paint refers to a paint containing the above-described pigment, resin, and water as a main liquid component.
The water-based paint refers to a water-based paint containing the above-described pigment, a resin, and water containing a trace amount of an organic solvent as a main liquid component.
The high solid paint refers to a paint containing the above-described pigment and having a non-volatile content (solid content) at the time of painting higher than that of a conventional paint (for example, about 15 to 25% higher).
Oil-based paints, water-based paints, and high solid paints only need to contain the above-described pigment, and can be manufactured and used by a general method.
Further, the powder coating refers to a powder coating that does not contain an organic solvent or water and is made only of a coating film forming component (that is, a resin and the pigment described above).
The powder coating material is a coating material obtained by cooling a dispersion obtained by uniformly heating and kneading the above-described pigment and resin, pulverizing to a predetermined particle size, and classifying. The powder coating material can be applied to an object to be coated by using, for example, an electrostatic coating machine.

  Of the paints described above, examples of the organic solvent used in oil paints, water paints, and high solid paints include hydrocarbon solvents such as toluene and xylene, ester solvents such as ethyl acetate and butyl acetate, and isopropyl alcohol. And alcohol solvents such as butanol, and ketone solvents such as ethyl methyl ketone and isobutyl methyl ketone.

  Resins used for oil-based paints, water-based paints, and high solid paints include vinyl chloride resin, alkyd resin, petroleum resin, phenol resin, acrylic resin, polyamide resin, polyurethane resin, and epoxy resin. The resin is not limited, and any resin that is generally used can be used as appropriate.

  Among the coating materials described above, as the resin (film forming resin) used for the powder coating material, when the powder coating material is a thermosetting powder coating material, for example, epoxy resin, epoxy-polyester resin, polyester Resin, acrylic resin, acrylic-polyester resin, phenol resin, fluorine resin, and the like can be used. When the powder coating is a thermoplastic powder coating, for example, a vinyl resin, a polyethylene resin, a polyamide resin, a fluorine resin, a modified polyolefin resin, or the like can be used. In addition, when using a thermosetting resin as resin for film formation, it is preferable to contain a hardening | curing agent and a hardening accelerator. What is necessary is just to select suitably a hardening | curing agent and hardening accelerator suitable for resin to be used.

(ink)
Moreover, an above described composition is ink, for example.
Examples of the ink in the present invention include oil-based ink, solvent ink, and water-based ink.

  The oil-based ink is an ink containing the above-described pigment and a non-volatile organic solvent as a main liquid component. Examples of the non-volatile organic solvent include silicone oils such as dimethyl silicone oil, fluorosilicone oil, amino-modified silicone oil, fluorine oil, liquid paraffin, and glycerin.

  The solvent ink is an ink containing the above-described pigment and a volatile organic solvent as a main liquid component. Examples of the volatile organic solvent include high boiling point and low volatility polyhydric alcohols such as glycerin, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, hexylene glycol, polyethylene glycol, and polypropylene glycol. And monoetherified products, dietherified products, and esterified products thereof. Examples of such include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, and the like. Examples of the volatile organic solvent include N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, monoethanolamine, dimethylaminoethanol, diethylaminoethanol, diethanolamine, N-butyl. Examples thereof include nitrogen-containing organic solvents such as diethanolamine, triisopropanolamine, and triethanolamine.

  The water-based ink is an ink containing the above-described pigment and water and / or a water-soluble organic solvent as a main liquid component. Examples of the water-soluble organic solvent include alcohols such as ethanol and n-propanol, polyhydric alcohols such as diethylene glycol and glycerin, and pyrrolidone solvents.

The oil-based ink, solvent ink, and water-based ink described above are, for example, letterpress ink, offset ink, gravure ink, screen ink, flexographic ink, ink for writing instruments (for example, water-based ballpoint pen ink and oil-based ballpoint pen ink), and ink jet printing. It can be used as various printing inks such as ink.
Moreover, the above-mentioned oil-based ink, solvent ink, and water-based ink can be used as ink for inkjet printing, for example.

  When oil-based inks, solvent inks, and water-based inks are used as these various printing inks, it is preferable to further add resin, oil, solvent, and the like so as to be suitable for each ink.

  Examples of the resin used as a relief printing ink and offset ink include petroleum resins, alkyd resins, rosin-modified phenol resins, rosins, cured rosins, ester gums, gilsonite, epoxy resins, and the like. , Vegetable oils, mineral oils, processed oils, and the like, and examples of the solvent include high boiling point petroleum solvents, glycols, alcohols, and the like.

  Examples of the resin used as the gravure ink include petroleum resin, rosin, cured rosin, ester gum, gilsonite, polyamide resin, urethane resin, and polyester resin. Examples of the solvent include aliphatic hydrocarbons. , Aromatic hydrocarbons (toluene, xylene), alcohols and the like.

  Examples of resins used as screen inks include petroleum resins, alkyd resins, rosin-modified phenol resins, acrylic resins, chlorinated rubbers, polyamide resins, urethane resins, and polyester resins. Examples of solvents include Aliphatic hydrocarbons, aromatic hydrocarbons (toluene, xylene), alcohols and the like can be mentioned.

  Examples of resins used as flexographic inks include nitrocellulose, acrylic resins, polyamide resins, polyurethane resins, and the like. Examples of solvents include alcohols such as isopropyl alcohol and ethanol, and ester solvents such as ethyl acetate. Can be mentioned.

  Examples of resins used as water-based ballpoint pen inks include cellulose ester, polyvinyl alcohol, polyacrylamide, polyethylene oxide, styrene maleic acid resin, rosin maleic acid resin, acrylic resin, vinyl acetate resin, styrene resin, and vinyl chloride. Resin, polyurethane, polyester, alkyd resin, and the like. Examples of the solvent include water, glycol solvent, fatty acid, glycol ether solvent, alcohol solvent, and the like.

  Examples of the resin when used as an oil-based ballpoint pen ink include vinyl resins, hydrocarbon resins, phenol resins, maleic resins, styrene / acrylic acid copolymers, ketone resins, and the like. For example, glycol solvents, fatty acids, glycol ether solvents, alcohol solvents, ester solvents and the like can be mentioned.

  Examples of the resin used as ink for inkjet printing include polyurethane resin, polyester resin, water-soluble acrylic resin, and the like. Solvents include water, alcohol, polyhydric alcohol, polyglycol, glycol ether, methyl ethyl ketone, A nitrogen polar solvent, a sulfur-containing polar solvent, etc. are mentioned.

(Mixing amount)
The blending amount of the pigment in the composition according to the present embodiment is preferably 0.1 to 70 parts by mass, for example, 1 to 50 parts by mass when the entire composition is 100 parts by mass. Part is more preferable, and 10 to 40 parts by mass is particularly preferable. Within this range, desired brightness can be obtained when used as ink. Moreover, since it is the objective of coloring if it is a coating material, the compounding quantity should just be selected suitably, For example, when the whole composition shall be 100 mass parts, it shall be 0.01-10 mass parts Is more preferable, 0.05 to 5 parts by mass is more preferable, and 0.1 to 30 parts by mass is particularly preferable. If it is this range, when using it as a coating material, a desired coloring degree can be obtained.

  The paints and inks described above use wax (polyethylene wax), compounds, extender pigments, dryers, dispersants, thickeners, gelling agents, thixotropy imparting agents, etc. as other additives as necessary. be able to.

  The paints and inks described above can be obtained by mixing the various materials described above. The mixing of the materials can be performed using a general mixing machine such as a mixing roll, a Banbury mixer, a kneader mixer, and the like.

(effect)
As described above, the composition according to the present embodiment can be obtained simply by pulverizing petroleum coke because the pigment to be blended can be easily obtained as compared with the case of blending carbon black. And can be manufactured relatively easily. Further, since the pigment to be blended can be obtained simply by pulverizing petroleum coke, it is easy to secure the raw material, and it is not necessary to treat the surface with fluorine gas, so that it can be produced relatively easily. Needless to say, the pigment to be blended may be surface-treated with fluorine gas. In this way, it is possible to obtain a composition with improved dispersion stability as a pigment. That is, the life of the ink and the stability as a product can be improved.

  The present invention will be described more specifically with reference to the following examples, but the present invention is not limited thereto.

<Petroleum coke>
Using pyrolysis residue (vacuum distillation residue oil) and slurry oil as pyrolysis raw material oil, pyrolysis treatment at 500 ° C. and 0.1 MPaG, pyrolysis treatment, pulverization with water jet, petroleum coke A Prepared as. Properties of petroleum coke A are shown in Table 1.

<Analysis of petroleum coke>
(moisture)
The analysis of the water content of petroleum coke A was performed according to JIS M 8811 for the sample before drying.
(Measurement of sulfur content in the dry state)
The sulfur content of petroleum coke in the dry state was measured as follows.
The sample was dried at 300 ° C. for 5 minutes, cooled to obtain a dry sample, and the mass in the dry state was measured. Subsequently, the sulfur content of the dried sample was measured according to JIS M 8819.
(ash)
The ash content of petroleum coke A was analyzed according to JIS M 8812 for dry samples.
(For CHN)
Analysis of the CHN content of petroleum coke A was performed on the dried sample in accordance with JIS M 8813.

[Example 1] Preparation of micronized coke (pigment) 20 kg of petroleum coke A was dried overnight at room temperature to obtain dried petroleum coke. The moisture content of the petroleum coke A after drying was 1% or less.
Thereafter, 11.4 kg of petroleum coke A was put into a cutter mill (VM-22 type manufactured by Seishin Enterprise Co., Ltd.) to obtain 10.8 kg of coarsely pulverized coke A. The yield at this time was 94.7%. Next, using a jet mill (STJ-200 manufactured by Seishin Enterprise Co., Ltd.), 8.8 kg of coarsely pulverized coke A was finely pulverized under the conditions of a nozzle pressure of 0.68 MPa and a supply rate of 4 kg / hour to obtain 8.5 kg of finely pulverized coke. A (ie pigment) was obtained. The yield by fine pulverization was 96.6%.
The particle size distribution of the obtained finely divided coke A was measured. The particle size distribution of finely pulverized coke A is measured using a laser diffraction / scattering particle size distribution measuring device (MICROTRAC manufactured by Nikkiso Co., Ltd.), using 200 g of ethanol as a solvent and a small amount of finely pulverized coke in ethanol. The dispersion was carried out in a solvent. The results are shown in FIG.
Moreover, the SEM photograph of the micronized coke A obtained in Example 1 is shown in FIGS. 2 (a), (b), and (c).

[Example 2] Preparation of ink A In a 100 cc beaker, 10 g of polyurethane resin (TA24-503A) manufactured by Hitachi Chemical Co., Ltd. and 60 g of toluene (domestic first grade) manufactured by Kokusan Chemical Co., Ltd. were weighed at room temperature and stirred for 5 minutes. A homogeneous solution was obtained by stirring. Thereafter, 3 g of the pigment obtained in Example 1 was weighed into an agate mortar, 7 g of the solution was dropped, and mixed with a pestle for 5 minutes to obtain ink A.
The mass ratio of polyurethane resin / toluene / pigment in ink A is 10/60/30 (mass%).

Example 3 Preparation of Ink B Ink B was obtained in the same procedure as in Example 2 except that the mass ratio of polyurethane resin / toluene / pigment was 10/85/5 (% by mass).

Example 4 Preparation of Ink C Ink C was prepared in the same procedure as in Example 2 except that the mass ratio of polyurethane resin / toluene / pigment was 7.7 / 53.8 / 38.5 (mass%). Obtained.

Example 5 Preparation of Ink D Ink D was obtained in the same procedure as in Example 2 except that the mass ratio of polyurethane resin / toluene / pigment was 10/89/1 (mass%).

[Comparative Example 1] Preparation of Ink X Ink X was obtained in the same procedure as in Example 2 except that the pigment was a commercially available carbon black for color (Toka Black # 8300 manufactured by Tokai Carbon Co., Ltd.). Unlike Examples 2 to 5, the solution and carbon black were not uniformly mixed.

[Example 6] Preparation of ink E (aqueous example)
In a 100 cc beaker, weigh 60 g of pure water at room temperature, 10 g of ethylene glycol (Wako first grade) manufactured by Wako Pure Chemical Industries, Ltd., and 10 g of liquid glue (Arabic Yamato) manufactured by Yamato Co., Ltd. Got. Thereafter, 2 g of the pigment obtained in Example 1 was weighed into an agate mortar, 9 g of the solution was dropped, and mixed with a pestle for 5 minutes to obtain ink E.
The mass ratio of pure water / ethylene glycol / liquid paste / pigment in the ink E is 9.1 / 54.5 / 18.2 / 18.2 (mass%).

[Example 7] Printing test Each of the inks A to D, X, and E obtained in Examples 2 to 6 and Comparative Example 1 was applied to a brush, and "CO" was described on the copy paper. The results are shown in FIGS.
As a result, as shown in FIGS. 3 to 6, it was confirmed that the inks A to D can be printed uniformly and become darker as the pigment content increases. Further, as shown in FIG. 8, even better printability was confirmed with ink E, which is a water-based ink. On the other hand, as shown in FIG. 7, the ink X was not attached to the paper.
Furthermore, after printing and drying, as a result of tactile sensation evaluation by tracing the printed portion with a finger, the presence of particles was not felt in inks A to E, but the presence of particles was confirmed in ink X.

  From the above results, it can be confirmed that a pigment can be obtained simply by pulverizing petroleum coke, and that an ink composition or a paint composition can be obtained simply by blending the pigment into a solvent and a resin. It was confirmed that printing and coating can be easily performed from an ink composition or a paint composition containing a pigment.

Claims (6)

  A pigment obtained by pulverizing petroleum coke.   The pigment according to claim 1, wherein the average particle size is 10 μm or less.   The pigment according to claim 1 or 2, wherein the petroleum coke has a sulfur content in a dry state of 5 to 12% by mass.   The oil-based coke is a dried product obtained by drying coke obtained by pyrolyzing a crude oil atmospheric distillation residue oil or a vacuum distillation residue oil at room temperature to 1500 ° C. Item 4. The pigment according to any one of Items 3.   A composition comprising at least one material selected from the group consisting of a solvent and a resin, and the pigment according to any one of claims 1 to 4.   The composition according to claim 5, which is a paint or an ink.