JP2002121413A - Method of producing cerulean pigment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cerulean pigment that has high color saturation and high clarity. SOLUTION: A mixture of ground β-type copper phthalocyanin (A) and ground ε-type copper phthalocyanin (B) or a ground product or a mixture of β-type copper phthalocyanin (A) and ε-type copper phthalocyanin (B) is ground and the resultant ground pigment mixture is pigmented to give the objective cerulean pigment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a method for producing a blue-black pigment useful as a coloring agent such as flexographic ink.

[0002]

2. Description of the Related Art Conventionally, in the field of gravure and flexographic inks,
In the field of paints and the like, blue-black inks and paints are mixed with inks and paints made from blue pigments and inks and paints made from purple pigments. It is carried out by a method of obtaining a dark blue color by converting the compounded pigment into an ink and a paint.

[0003]

However, there are many problems with the described method. For example, the above-mentioned method of obtaining a gravure / flexo ink having a blue-black color tone by mixing the pigments of the respective colors or mixing the inks of the respective colors has the following disadvantages.

(1) Even when a separately prepared blue pigment and a violet pigment or an α-type copper phthalocyanine pigment or an ε-type copper phthalocyanine pigment having a blue-black color tone are mixed, the color becomes unclear due to the mixture. And the sharpness of each pigment cannot be obtained. (2) In the ink-forming step, in addition to the drawback of (1), it is necessary to produce two kinds of inks of an α-type copper phthalocyanine pigment and an ε-type copper phthalocyanine pigment having a blue color and a violet or dark blue color tone, and the process is complicated It is. (3) Purple pigments, α-type copper phthalocyanine pigments, and ε-type copper phthalocyanine pigments are more expensive than β-type copper phthalocyanine pigments generally used as blue pigments, which leads to an increase in cost.

[0005]

In view of the above situation,
The present inventors have conducted intensive studies on a method for producing a direct blue-black pigment at low cost, and as a result, for example, a mixture of a milled product of β-type copper phthalocyanine and a milled product of ε-type copper phthalocyanine was subjected to a pigmentation treatment, and the above-described method was used. The present inventors have found that a blue-black pigment having high chroma, vividness, and high coloring power and good dispersibility can be obtained without disadvantages, and the present invention has been achieved.

That is, the present invention relates to a mixture of a ground β-type copper phthalocyanine (A) and a ground ε-type copper phthalocyanine (B), or a mixture of a β-type copper phthalocyanine (A) and an ε-type copper phthalocyanine (B). The present invention provides a method for producing a blue-black pigment, which is characterized by subjecting a ground product of the above to pigmentation treatment.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. In the present invention, in obtaining a blue-black pigment, the greatest feature is that the final pigments are not mixed with each other to form a blue-black color, but are mixed at the stage of the pigment precursor as a ground material and then pigmented. I do.

In the present invention, the pigmentation is carried out using a mixture of a milled product of β-type copper phthalocyanine (A) and a milled product of ε-type copper phthalocyanine (B), or β-type copper phthalocyanine (A) and ε-type copper phthalocyanine ( This is a ground product of the mixture with (B).

As the β-type copper phthalocyanine (A) and the ε-type copper phthalocyanine (B) used in the present invention, any known and commonly used ones can be used. These can all be manufactured by a conventionally known method.

The β-type copper phthalocyanine (A) used in the present invention has a Bragg angle 2θ (tolerable range of 0.2 degree) of 7.0, 9.2, 1 according to X-ray diffraction spectrum (CuKα ray).
It is known to have relatively strong peaks at 8.1, 18.6, 23.7 degrees and the like.
For example, it can be manufactured by the following method. (1) Reaction of phthalic anhydride or a derivative thereof, urea or a derivative thereof, and a copper source (Wyler method). (2) Reaction of phthalodinitrile and a copper source (phthalodinitrile method).

In these reactions, phthalic acid derivatives include, for example, phthalic acid salts, phthalic anhydride, phthalimide, phthalamic acid and salts or esters thereof, and phthalonitrile. Urea derivatives include, for example, urea and ammonia. Examples thereof include metal copper, cuprous or cupric halides, copper oxide, copper sulfate, copper sulfide, and copper hydroxide.

Examples of the catalyst that can be used in the above reaction include molybdenum compounds such as ammonium molybdate and molybdenum oxide, titanium compounds such as titanium tetrachloride and titanate, zirconium compounds such as zirconium chloride and zirconium carbonate, and antimony oxide. ,
Examples of the organic solvent include boric acid and the like, for example, aromatic hydrocarbons such as alkylbenzene and alkylnaphthalene, alicyclic hydrocarbons such as alkylcyclohexane and decalin, aliphatic hydrocarbons such as decane and dodecane, and aromatic hydrocarbons such as nitrobenzene and nitrotoluene. And aromatic halogenated hydrocarbons such as aromatic nitro compounds, trichlorobenzene and chloronaphthalene.

In the production of β-type copper phthalocyanine by the reaction of the above-mentioned production method (1) or (2), a catalyst is added to each of the above raw materials, if necessary, in the presence or absence of an organic solvent. So, for example, 180 ° C-3
What is necessary is just to heat at 00 degreeC for 1 to 5 hours.

By crystallizing the thus obtained crude product, β-type copper phthalocyanine (A) can be obtained.

The ε-type copper phthalocyanine (B) used in the present invention is relatively strong in the Bragg angle 2θ (allowable range 0.2 degree) 7.7, 9.3, etc. according to the X-ray diffraction spectrum (CuKα ray). It is known that it has a peak, and can be produced, for example, by the following method. (1) α-type copper phthalocyanine is dry-ground to form a mixture of α-type copper phthalocyanine and ε-type copper phthalocyanine, which is heated and stirred in a large excess of an organic solvent (UK Patent No.
1411880). Here, the α-type copper phthalocyanine may have a relatively strong peak at a Bragg angle 2θ (allowable range of 0.2 degrees) 6.8, 7.3, or the like in an X-ray diffraction spectrum (CuKα ray). It is known, and the acid pasting method and the acid slurry method, specifically, for example, dissolving or suspending copper phthalocyanine obtained by each of the above-mentioned production methods in concentrated sulfuric acid, and pouring it into water to re-use. It can be manufactured by precipitating, washing until neutral and taking out. (2) An organic compound capable of forming a phthalocyanine ring is reacted with a copper compound in an organic solvent containing a copper phthalocyanine sulfonic acid derivative (JP-A-57-149358).

As the method for producing ε-type copper phthalocyanine (A), the method (1) is easier to produce,
It also has an economically advantageous feature of being inexpensive and is preferable.

In the present invention, a mixture of a ground product obtained by grinding only the β-type copper phthalocyanine (A) and a ground product obtained by grinding only the ε-type copper phthalocyanine (B), or β
A milled product of a mixture of copper phthalocyanine (A) and copper phthalocyanine (B) is pigmented.

The milled material obtained by grinding only β-type copper phthalocyanine (A) is a mixture containing α-type copper phthalocyanine and β-type copper phthalocyanine, and the milled material obtained by grinding only ε-type copper phthalocyanine (B) is as follows. It becomes a mixture containing α-type copper phthalocyanine and ε-type copper phthalocyanine.

Here, as the ground ε-type copper phthalocyanine (B), dry ground ε-type copper phthalocyanine (A) can be most preferably used. A mixture of α-type copper phthalocyanine produced by a pasting method or the like can also be used. Further, instead of the ε-type copper phthalocyanine (A), an ε-type copper phthalocyanine pigment produced by a conventionally known method can be used.

Β-type copper phthalocyanine (A) and / or ε
By grinding, the type copper phthalocyanine (B) has a smaller average primary particle diameter than before grinding, for example, 0.00
It can be 1 to 0.1 μm. In order for the obtained milled material to exhibit its effect effectively, it is preferable that the average primary particle diameter of the milled material is 0.001 to 0.005 μm.

In the present invention, the average primary particle diameter is determined by using a transmission electron microscope to disperse the pigment in an inert liquid medium by ultrasonic wave, dissolve the pigment, take a photograph thereof, It is the result of averaging the results of measuring the major diameters of 50 existing pigment particles.

In the following pigmentation, a mixture of the β-type copper phthalocyanine (A) and the ε-type copper phthalocyanine (B) alone ground to have the same predetermined average primary particle diameter (referred to as a mixture of ground materials) is used. Or a mixture obtained by grinding a mixture of β-type copper phthalocyanine (A) and ε-type copper phthalocyanine (B) so as to have a predetermined average primary particle diameter (referred to as a ground mixture). You can do it. These have the same effect as long as the average primary particle diameter is the same.

The weight ratio of the β-type copper phthalocyanine (A) and the ε-type copper phthalocyanine (B) in the charged state at the time of obtaining the mixture of the ground materials or the ground material of the mixture is as follows: the former (A): the latter (B) = 80 : 20 to 97: 3.

In order to obtain a mixture of the above-mentioned crushed materials and / or a crushed material of the mixture, known and commonly used crushing means can be employed. As the grinding means, dry grinding is more preferable than wet grinding because excessive aggregation is less likely to occur, crystal conversion can be performed more easily, and workability is excellent.

Dry milling is carried out, for example, in the presence or absence of water-soluble inorganic salts such as sodium chloride and sodium sulfate which do not dissolve copper phthalocyanine and do not dissolve them.
It can be easily carried out using a ball mill, vibration mill or the like. Dry grinding is more preferably performed in the presence of a grinding aid and in the presence of a dispersion medium such as glass beads and metal beads. In this case, it is preferable not to use the water-soluble inorganic salt in the dry grinding, but if it is used, it is removed by washing with water.

The pigmentation treatment can be carried out by the same method as the conventionally known pigmentation method for copper phthalocyanine. Specific examples of the pigmentation treatment include the following methods. (1) Solvent method The mixture of the above-mentioned crushed materials and / or the crushed material of the mixture is mixed and stirred with a large excess of a liquid medium containing an organic solvent having an effect of crystal transition and / or crystal growth as an essential component. (2) Solvent milling method The mixture of the ground materials and / or the ground material of the mixture is mechanically ground with a liquid medium containing a relatively small amount of an organic solvent as an essential component. A liquid medium can be prepared by using water in combination with the organic solvent. At this time, it is preferable to use the water-soluble inorganic salt in combination with an organic solvent (this is a solvent salt milling method). (3) Acid paste method (acid slurry method) After dissolving or suspending the mixture of the crushed material and / or the crushed material of the mixture in concentrated sulfuric acid, the mixture is poured into water and reprecipitated.
In the method (1) or (2), the organic solvent may be used alone or in combination of two or more.

In the present invention, the above method (1) or (2) is a method for producing a copper phthalocyaninine pigment exhibiting β-type in the X-ray diffraction spectrum and effective as a means for obtaining the effects of the present invention. Among them, the solvent salt milling method in the above (2) is the most preferable in that the aspect ratio becomes smaller than the aspect ratio of the pigment particles (granular crystals instead of needle-like crystals are obtained).

By the above operation, the crystal transition and / or the crystal
Growing is performed, for example,
The resulting copper phthalocyanine pigment can be obtained. this
Copper phthalocyanine pigment is β-type on X-ray diffraction spectrum
The same as copper phthalocyanine pigment, ε-type copper phthalocyanine
Those containing copper phthalocyanine derivatives as the nin (B)
When used, this derivative has an infrared absorption spectrum
(IR) confirms its presence. Thus, β-type copper foil
Although it is a tarocyanine pigment, the hue is L^*a^*b ^*Color
A in the system^*Dark blue with a value in the range of -20 to -25
A pigment is obtained. .

A pigmentation treatment method which is effective in the present invention,
In the solvent method, an organic solvent capable of crystal transition to a stable β-type crystal is indispensably used. In the treatment method, when a liquid medium containing only an organic solvent is used, a liquid medium containing an organic solvent and water may be used. Such a treatment may be performed at room temperature, but is preferably performed under heating.

The amount of the liquid medium used at this time is 300 to 100 parts by weight of the mixture of the ground material or the ground material of the mixture.
1500 parts by weight. When a liquid medium containing an organic solvent and water is used, an organic solvent having no affinity for water may be used as an emulsion with a surfactant.

Examples of the organic solvent include hydrocarbons such as toluene, xylene, and mineral spirits; ketones such as methyl ethyl ketone, methyl butyl ketone, methyl isobutyl ketone and cyclohexanone;
Alcohols such as butanol, isopropyl alcohol, isobutanol, methyl cellosolve, butyl cellosolve, and cyclohexanol; halogenated hydrocarbons such as trichloroethane, trichloroethylene and chlorobenzene; ethers such as tetrahydrofuran, dioxane, diglyme, and anisole; ethyl acetate and propyl acetate ,
Esters such as butyl acetate, cellosolve acetate, butyl cellosolve acetate; dimethylformamide;
Amides such as N-methylpyrrolidone are exemplified. Further, a mixture of two or more of these solvents may be used. In addition, water can be added to these solvents and used in the form of an aqueous solution or a liquid-liquid two-phase system.

After the treatment with the liquid medium, the solvent is removed by a distillation operation, a decompression operation, or the like. In the case of only the treatment with an organic solvent, a dry pigment is obtained.
In the case of a liquid two-phase system, it can be converted into a water slurry to obtain a dried pigment through a filtration step and a drying step. In addition, in the case of an organic solvent-water aqueous solution, after directly filtering without performing operations such as distillation and decompression, washing until the organic solvent component in the pigment is completely removed, a dry pigment is obtained through a drying step. Can also. Alternatively, it can be dried with a spray drier or the like in the state of a dispersion containing washing water.

Among the solvent milling methods which are another pigmentation treatment method which is effective in the present invention, the most suitable solvent salt milling method is to mix a water-soluble inorganic salt and an organic solvent which are insoluble in an organic solvent with a ground material. And / or adjust the milled material of the mixture to obtain the most effective grinding viscosity, for example, after mechanically milling with a mill, take out the milled material into water, and filter the inorganic salt, organic By performing pigmentation by removing the solvent, a blue-black pigment can be obtained.

The conditions under which the ground material is most effectively obtained by the grinding viscosity are appropriately adjusted depending on the type of the grinding machine, etc., and the grinding is carried out in advance under various conditions, and the actual grinding is carried out from among them. What is necessary is just to select the condition which becomes the highest crushing efficiency.

As the inorganic salt, those described above can be used, and as the organic solvent, an organic solvent which has no reactivity with the above-mentioned copper phthalocyanine and does not dissolve them can be used.

More specifically, 100 to 100 parts by weight of the mixture of the ground materials or the ground material of the mixture are mixed with 100 to 10 parts of the inorganic salt.
100 parts by weight and 100 to 150 parts by weight of an organic solvent, for example, mechanically grind for 2 to 10 hours with a grinder such as a kneader or a Banbury mixer. A method of obtaining a pigment by removing the solvent is mentioned.

After removing the inorganic salt and the organic solvent, if necessary, washing with water or hot water is repeated, and filtration is performed to further reduce inorganic salts and impurities. For example, when washing, the washing water has a specific conductivity of 10%.
It is preferable to carry out the reaction until it becomes 0 S / m × 10 ⁻⁴ or less.

The wet product thus obtained can be dried, for example, at 50 to 200 ° C. in a dryer or the like to obtain a dried blue-black pigment. Of course, it is also possible to dry with a spray drier or the like in the state of a dispersion liquid to which water has been added after the filtration, or in the state of a dispersion liquid containing washing water.

The dried pigment obtained by the pigmentation can be easily loosened to such an extent that it can be used as it is, but if necessary, it may be further pulverized or used for sharpening the particle size distribution. Then, classification may be performed.

The blue-black pigment thus obtained has an aspect ratio of 3 to 15, but the blue-black pigment produced by the above-mentioned solvent salt milling method becomes 3 to 6, and is produced by other production methods. It is preferable because the aspect ratio becomes smaller than that obtained by the above method.

In the present invention, the aspect ratio is obtained by averaging the results of the minor axis measured in the same manner as the average primary particle diameter,
It is represented by the ratio (major axis / minor axis) of the average primary particle diameter (major axis) to the minor axis.

The blue-black pigment of the present invention can be used in the known and used fields,
For example, general-purpose inks such as gravure inks and flexo inks, general-purpose paints such as baking coatings, UV coatings, and ever-drying coatings, coloring of thermoplastic molded articles, toners for electrophotography, jet printer inks, and known and common recording materials such as color filters. It can be used for various applications.

The blue-black pigment of the present invention is particularly suitable for preparing a gravure ink or a flexographic ink.

Gravure or flexographic inks are
For example, it can be prepared by dispersing the blue-black pigment obtained in the present invention in a vehicle. The vehicle is
It is usually prepared by uniformly mixing a resin, water and / or an organic solvent as a main component and other additives. When preparing an oil-based ink, use a hydrophobic organic solvent as a solvent, a resin that dissolves in the solvent, and when preparing an aqueous ink, use water or water and a hydrophilic organic solvent as a solvent, stably in the solvent. Resins that dissolve or disperse are used.

The water-based flexographic ink is preferable because it is less likely to cause fire and pollution than the oil-based flexographic ink. The blue-black pigment obtained according to the present invention most effectively shows its characteristics in an aqueous flexographic ink. The aqueous flexographic ink is required to have the highest fluidity among various gravure inks and various flexographic inks, and the viscosity of the obtained aqueous flexographic ink is obtained by using a pigment having a smaller aspect ratio as described above. Is lower, and the fluidity thereof can be further improved.

The vehicle used for the aqueous flexographic ink is
It is usually prepared using resins, solvents, plasticizers, waxes, lubricants, defoamers and the like.

Examples of the resin include natural resin-based shellac, synthetic resin-based rosin-modified maleic resin,
In addition to styrene-acrylic acid resin, acrylic acid-acrylic acid ester resin, polyester resin, water-soluble polyamide resin, aqueous polyurethane resin, and the like. The solvent may be water alone, but a hydrophilic organic solvent is generally used in combination. As the hydrophilic organic solvent, for example, alcohol solvents such as methanol, ethanol, propanol, and butanol are preferably used.

In preparing the ink, the pigment composition of the present invention is used in an amount of 200 to 60 parts by weight per 100 parts by weight of the resin nonvolatile matter.
It is prepared so as to be 0 parts by weight.

The ink thus obtained can be printed by coating and drying on a known and commonly used printing medium. Examples of the print medium include paper, resin-coated paper,
Examples include synthetic resin films and sheets.

[0050]

EXAMPLES Examples, reference examples and comparative examples will be described below. In Examples, Reference Examples and Comparative Examples, “parts” means “parts by weight” and “%” means “% by weight”.

According to the Weyler method, β-type copper phthalocyanine (A) was obtained and dry-ground by an attritor mill to obtain a ground material having an average primary particle diameter of 0.002 μm. This milled product of β-type copper phthalocyanine was a mixture of α-type copper phthalocyanine and β-type copper phthalocyanine.

Ε-type copper phthalocyanine (B) according to a conventional method
This was dry-ground by an attritor mill to obtain a ground material having an average primary particle diameter of 0.002 μm. The ground ε-type copper phthalocyanine was a mixture of α-type copper phthalocyanine and ε-type copper phthalocyanine.

Example 1 A mixture of 95% of the above-mentioned milled product of β-type copper phthalocyanine and 5% of the above milled product of ε-type copper phthalocyanine, 200 parts of water
And 100 parts of isobutanol were charged into a separable flask equipped with a reflux tube, and a reflux operation was performed at a temperature of 89 ° C. for 6 hours. Thereafter, in the distillation operation, the temperature was gradually increased so that the temperature of the water-moistened liquid became 100 ° C., thereby completely removing isobutanol. Thereafter, the mixture was filtered and washed with a large amount of water, and dried to obtain 58 parts of a blue-black pigment. According to the X-ray diffraction spectrum, the blue-black pigment was of the β type. The average primary particle diameter of this pigment was 0.1 μm, and the aspect ratio was 11.

Example 2 The procedure of Example 1 was repeated, except that the ground β-type copper phthalocyanine was 90% and the mixture of ground ε-type copper phthalocyanine 10% was used. Obtained. According to the X-ray diffraction spectrum, the blue-black pigment was of the β type. The average primary particle size of this pigment is 0.1.
05 μm and the aspect ratio was 9.

Example 3 The procedure of Example 1 was repeated, except that the milled β-copper phthalocyanine was changed to a mixture of 85% and the milled ε-copper phthalocyanine, 15%. Obtained. According to the X-ray diffraction spectrum, the blue-black pigment was of the β type. The average primary particle size of this pigment is 0.1.
03 μm and the aspect ratio was 8.

Example 4 300 parts of a mixture of 95% of the above-mentioned milled β-type copper phthalocyanine and 5% of the above-mentioned ground ε-type copper phthalocyanine, and salt 21
Then, 00 parts were charged into an 8 L double-arm kneader, and diethylene glycol was added thereto while adjusting so that the ground material was most effectively ground, and ground at 90 ° C. for 7 hours to perform a pigmentation treatment. Next, the ground material was taken out into water, stirred sufficiently, filtered, washed with a large amount of water, and dried to obtain 295 parts of a blue-black pigment. According to the X-ray diffraction spectrum, the blue-black pigment was of the β type. The average primary particle size of this pigment is
The thickness was 0.05 μm, and the aspect ratio was 5.

Example 5 The procedure of Example 4 was repeated, except that the ground β-copper phthalocyanine was converted to a mixture of 90% and the ground ε-copper phthalocyanine 10%, and 296 parts of the blue-blue pigment were added. Obtained. According to the X-ray diffraction spectrum, the blue-black pigment was of the β type. The average primary particle size of this pigment is 0.1.
05 μm and aspect ratio was 4.

Example 6 The procedure of Example 4 was repeated, except that the ground β-type copper phthalocyanine was used as a mixture of 85% and the ground ε-type copper phthalocyanine was ground at 15%. Obtained. According to the X-ray diffraction spectrum, the blue-black pigment was of the β type. The average primary particle size of this pigment is 0.1.
03 μm and the aspect ratio was 3.5.

Reference Example 60 parts of the above-mentioned β-type copper phthalocyanine ground material was mixed with 200 parts of water.
And 100 parts of isobutanol were charged into a separable flask equipped with a reflux tube, and a reflux operation was performed at a temperature of 89 ° C. for 6 hours. Thereafter, in the distillation operation, the temperature was gradually increased so that the temperature of the water-moistened liquid became 100 ° C., thereby completely removing isobutanol. Then, after filtering and washing with a large amount of water, it was dried to obtain a blue-black pigment. This azure blue pigment is X
According to the line diffraction spectrum, it was β-type. The average primary particle size of this pigment was 0.05 μm. The average primary particle size was 0.2 μm and the aspect ratio was 14.

Preparation of Aqueous Flexographic Inks Example 1, Example 2, Example 3, Example 4, Example 5,
The blue-blue pigment obtained in Example 6, the copper phthalocyanine pigment obtained in Reference Example, and the ε-type copper phthalocyanine pigment (Fast Gen Blue EP manufactured by Dainippon Ink and Chemicals, Inc.)
-7S) 40 parts, vehicle (Johncryl 61J manufactured by Johnson Wax Co., Ltd., styrene- (meth) acrylic acid-
An aqueous dispersion of a (meth) acrylate copolymer. 34.5 parts, nonvolatile content 31%), IPA (isopropanol)
34.5 parts, 0.2 part of defoamer 1/8 steel beads 2
50 parts were placed in a 250 cc container, and operated in a paint mill (manufactured by Toyo Seiki Co., Ltd.) for 30 minutes to obtain a blue-black aqueous flexo ink.

Comparative Example 1 A 95% aqueous flexo ink obtained from the copper phthalocyanine pigment obtained in Reference Example and 5% an aqueous flexo ink obtained from the ε-type copper phthalocyanine pigment were mixed for 10 minutes in the above-mentioned paint mill. To obtain a deep blue aqueous flexo ink.

Comparative Example 2 90% of an aqueous flexographic ink obtained from the copper phthalocyanine pigment obtained in the reference example and 10% of an aqueous flexographic ink obtained from the ε-type copper phthalocyanine pigment were mixed for 10 minutes in the paint mill described above. To obtain a deep blue aqueous flexo ink.

COMPARATIVE EXAMPLE 3 85% of the aqueous flexographic ink obtained from the copper phthalocyanine pigment obtained in the reference example and 15% of the aqueous flexographic ink obtained from the ε-type copper phthalocyanine pigment were mixed for 10 minutes in the paint mill described above. To obtain a deep blue aqueous flexo ink.

An aqueous flexographic ink was prepared by the above method. Table 1 shows the results. The evaluation was shown with an aqueous flexographic ink.

The fluidity of the aqueous flexographic ink was measured with a B-type viscometer (RB80L viscometer). As a result, the viscosity of the aqueous flexographic ink of Example 1 (1356 mPa · s) was superior to the viscosity of Example 4 (352 mPa · s). Similarly, Example 5 (1286 mPa · s)
Example 2 (312 mPa · s) and Example 6 (1
182 mPa · s) and Example 3 (273 mPa · s).
s) had excellent ink fluidity.

[0066]

[Table 1] Table 1

Evaluation method * 1 Sharpness The obtained aqueous flexographic ink was spread on a high quality paper using a 0.15 mm bar coater, and the sharpness was visually judged.

* 2 Gloss The developed material used for the evaluation of sharpness was measured using a haze-gloss meter (BY
The gloss was measured by K. Gardner). Comparative Example 1
A comparison of Example 1, Example 2, Example 3, Example 4, Example 5, Example 6, Example 6, Comparative Example 2, and Comparative Example 3 was quantified as 00 (standard).

* 3 Coloring power 1.5 parts of each aqueous flexographic ink and 35 parts of white ink (Daiflex ACT709 white, manufactured by Dainippon Ink and Chemicals, Inc.) obtained in the sharpness evaluation were mixed in a 100 cc container and mixed well to give a light color. An ink was obtained. 0.15 of the obtained light color ink
Using a bar coater to spread the color on high quality paper, SPECTRAFLA
The coloring power was measured using SH500 (manufactured by Data Color). The comparison of Example 1, Example 2, Example 3, Example 4, Example 5, Example 6, Example 2, Comparative Example 2, and Comparative Example 3 was quantified using Comparative Example 1 as 100 (standard).

* 4 Hue The light colored ink obtained in the evaluation of tinting strength was subjected to SPECTRAFLASH
The a * value was measured for Example 1, Example 2, Example 3, Example 4, Example 5, Example 6, Comparative Example 1, Comparative Example 2, and Comparative Example 3 at 500 (manufactured by Data Color). . Where a
* The larger the value (the closer to 0 in the case of blue),
The toning of the ε-type copper phthalocyanine pigment, which tends to be reddish and has a high pigment unit price, is reduced, and it becomes a pigment highly demanded by users as a blue-black pigment.

[0071]

According to the present invention, the thus obtained dark blue color is obtained.
The pigments are crushed β-type copper phthalocyanine (A) and ε-type copper
A mixture of ground phthalocyanine (B) or β-type copper
Phthalocyanine (B) and ε-type copper phthalocyanine (B)
A mixture of the mixture and the pigment obtained by pigmentation
Of a mixed pigment made into a dark blue color by blending a pigment and a purple pigment.
Inks and blends of blue and purple pigment inks
Hue is clearer and a ^*Large value and high coloring power
Can be obtained.

Claims (4)

[Claims] A mixture of a milled product of β-type copper phthalocyanine (A) and a milled product of ε-type copper phthalocyanine (B), or
A method for producing a blue-black pigment, comprising subjecting a ground material of a mixture of β-type copper phthalocyanine (B) and ε-type copper phthalocyanine (B) to pigmentation treatment. 2. A mixture of milled β-copper phthalocyanine (A) and milled ε-copper phthalocyanine (B), or
A method for producing a blue-black pigment for gravure flexographic ink, comprising subjecting a ground mixture of a mixture of β-type copper phthalocyanine (B) and ε-type copper phthalocyanine (B) to pigmentation. 3. The method for producing a blue-black pigment according to claim 1, wherein the method of the pigmentation treatment is a solvent method or a solvent milling method. . 4. The method according to claim 2, wherein the gravure flexographic ink is an aqueous flexographic ink.