JPH0813937B2 - Pigment manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a method for producing a finely divided pigment. More specifically, it relates to a method for producing a finely divided pigment in which a crude pigment is crushed by a disperser equipped with a dispersion medium.

(Prior Art) Since the crude organic pigment just synthesized is obtained as coarse particles, it has poor coloring power even if it is used as it is, and its value as a coloring material for printing inks, paints, colorants for plastics, etc. is small. . Therefore, conversion from a crude pigment to a pigment form is performed by pulverization or the like. However, if the crude organic pigment is pulverized as it is, strong pulverization and agglomeration occur, and therefore only those having extremely low tinting strength can be obtained.

Currently, the most commonly used method is a wet method in which a grinding aid is ground together with a wetting agent such as polyethylene glycol by a kneader, Banbury mixer, edge runner, or the like. The finely divided pigment is obtained by dissolving the grinding aid and the wetting agent in water and removing them.
However, this method has a problem that a waste liquid containing a large amount of inorganic salt and a wetting agent is produced. Although inorganic salts and wetting agents are recovered from this wastewater by distillation, etc., the wastewater still has a high COD value that causes environmental problems even after recovery, so it is necessary to consider wastewater treatment. Therefore, the method for producing a pigment obtained by such a process is wasteful in terms of energy and is not always an economical method.

As a method for preparing a pigment such as a phthalocyanine pigment by a dry method, it is pulverized by a pulverizer such as a ball mill, a vibration mill or an attritor in the presence of a crystallization solvent together with a pulverizing aid such as aluminum sulfate, sodium chloride or calcium chloride. Techniques for changing the crystal morphology of the emulsified pigment are disclosed in JP-A-56-22356, USP264564, JP-B-37-16166 and the like. However, the pigments obtained by these methods have the drawbacks that they have low tinting strength and gloss, and that bronzing occurs, so that the applications of the obtained pigments are currently limited.

(Problems to be Solved by the Invention) An object of the present invention is to obtain an organic pigment which is excellent in coloring power and luster and has less bronze generated by an economically advantageous method.

[Structure of Invention]

(Means for Solving the Problems) The present invention is to pulverize a crude pigment and 0.3 to 10 times by weight of the crude pigment at room temperature solid and water-soluble organic compound powder with a disperser equipped with a dispersion medium. Then, the present invention relates to a method for producing a finely divided pigment, which comprises dissolving and removing the organic compound powder in water by bringing the pulverized mixture into contact with a large amount of water.

In the present invention, crude pigments include organic pigments such as crude phthalocyanine, crude quinacridone, crude anthraquinone, crude perinone pigments and crude dioxazine pigments.

The organic compound powder used as a grinding aid is fixed at room temperature (about 25 ° C), and has an amino group, a hydroxyl group or its metal salt, a carboxyl group or its metal salt,
And having a functional group selected from a sulfonic acid group or a metal salt thereof, preferably crystalline and having a molecular weight of about 600
It is the following compound. The organic compound is water-soluble, and the term “water-soluble” as used herein includes the property of being dissolved in alkaline water and acidic water. For this reason, it is preferable to have the above water-soluble functional group, but the structure of the organic compound is not particularly limited as long as it is water-soluble.

Examples of such organic compounds include m-phenylenediamine, m-nitroaniline, m-aminophenol, p-aminosalicylic acid, methanilic acid, phenol, phenol-2,
4-disulfonic acid, p-hydroxybenzoic acid, resorcin, hydroquinone, 3-aminosalicylic acid, p-aminophenol, benzene-m-disulfonic acid, 1,2-dichlorobenzene-4-sulfonic acid, 6-chloro-2- Aminophenol-4-sulfonic acid, 3,4-dichloroaniline-6-sulfonic acid, 4,5-dichloro-2-aminophenol, p-chlorophenol, chlorobenzene-p-sulfonic acid, 2-
Aminophenol-4-sulfonic acid, aniline-2,5-
Disulfonic acid, aniline-o-sulfonic acid, p-toluidine, toluene-p-sulfonic acid, 6-chloro-3-toluidine-4-sulfonic acid (C acid), toluene-2,4-disulfonic acid, m-amino Benzoic acid, naphthalene-2-sulfonic acid, naphthalene-1,6-disulfonic acid, naphthalene-
2,7-disulfonic acid, naphthalene-2,6-disulfonic acid, 1
-Naphthol-3,6-disulfonic acid, 1-naphthylamine-3,6-disulfonic acid, 1-naphthol-3,8-disulfonic acid, 1-naphthylamine-3,6-disulfonic acid, 1-naphthol-3,8 -Disulfonic acid, 1-naphthylamine-3,6,8-
Trisulfonic acid, 1,8-naphthylenediamine-3,6-disulfonic acid (H acid), 2-naphthol-7-sulfonic acid (F
Acid), 1,8-dihydroxynaphthalene-3,6-disulfonic acid, 8-chloronaphthol-3,6-disulfonic acid, 2,7-dihydroxynaphthalene, 1-naphthylamine-3,7-disulfonic acid, 1,5 -Naphthyldiamine-3,7-disulfonic acid,
1,5-naphthalenediamine-3,7-disulfonic acid, 2,6-dihydroxynaphthalene-2-amino-3-naphthol-
6-sulfonic acid, 2-amino-8-naphthol-3,6-disulfonic acid, 2-phenylamino-8-naphthol-6-
Sulfonic acid, β-naphthylamine, 2-naphthol-1-
Sulfonic acid, 2-hydroxy-3-naphthenic acid, 2-naphthylamine-8-sulfonic acid (badish acid), 2-naphthylamine-7-sulfonic acid (digital acid), 2-naphthylamine-5-sulfonic acid, 2- Amino-8-naphthol-6-sulfonic acid (γ acid), 1,2-naphthylamine-5,7
-Disulfonic acid, 2-naphthylamine-1,5-disulfonic acid, 1-amino-2-naphthol, 2-naphthylamine 1,5,
7-Trisulfonic acid, 1-amino-8-naphthol-4,6-
Disulfonic acid (K acid), 1-naphthol-5-sulfonic acid, 1,5-naphthalenediol, 1-chloronaphthalene-8
-Sulfonic acid, 1-naphthylamine-8-sulfonic acid (perry acid), 1-naphthylamine-4,8-disulfonic acid, 1-
Amino-8-naphthol-4-sulfonic acid (S acid), 1,8
-Dihydroxynaphthalene-4-sulfonic acid (dioxy S acid), 1-naphthol-4,8-disulfonic acid, 1-naphthol-8-sulfonic acid, 1-naphthol-2,4,7-trisulfonic acid, 1- Hydroxy-2-naphthenic acid, α-naphthylamine, 1-naphthylamine-4-sulfonic acid, 1-naphthol-4-sulfonic acid, 1-naphthylamine-4-7-
Disulfonic acid, 1-naphthylamine-4-6sulfonic acid (daric acid), 1,5-naphthyldiamine, 5-amino-8-
Hydroxy-1,4-naphthoquinodiimine (imine base), 1,1'-binaphthalene-8,8'-dicarboxylic acid (dyneric acid), 1,8-naphthalenediamine, α-naphthalenehydroquinone, 3-aminoanhydrous There are aromatic compounds such as phthalic acid, 4-aminophthalic anhydride, m-aminobenzoic acid, phthalimide, 5-sulfoanthranilic acid, quinizarin and anthracene brown, and aliphatic compounds such as lauric acid and stearyl acid.

The crushing is performed by using a crusher equipped with a dispersion medium such as a ball mill, a vibration mill, and an attritor, which contains the crude pigment and the water-soluble organic compound as a crushing aid. The amount of water-soluble organic compound used is 0.3 to 10 times the weight of the crude organic pigment,
It is preferably 0.3 to 8 times by weight, and if less than 0.3 times by weight, the aggregation mitigating effect in pulverization is insufficient, and only pigments with strong aggregation and low coloring power can be obtained. It is not preferable because it decreases.

The temperature during pulverization needs to be from room temperature to a temperature at which the water-soluble organic compound which is a pulverization aid can maintain powder. The crushing time varies depending on the type of crude pigment, the type of crusher, the amount of crushing aid used, and the time of addition, but it is generally 5 minutes to 120 hours.

If necessary, for crystallization, for example, benzene, toluene, xylene, chlorobenzene, nitrobenzene, tetrahydrofuran, ethanolamine, aniline, pyridine, dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, trichloroethylene, tetrachloroethylene, cellulose acetate, butyl acetate. , Acetone, methyl ethyl ketone, methanol, ethanol, butanol, propanol, isopropanol, etc. may be added and pulverized. This crystallization solvent is added for the purpose of loosening the crystal transition and aggregation of the crushed pigment, but it is necessary to make it an amount that can maintain the properties of the water-soluble organic compound as a powder, and usually it is necessary to 0.1 to 20
%, Preferably 0.5 to 15% by weight. The crystallization solvent may be added before or during the pulverization.

In the present invention, the pulverization may be performed in the presence of water. However, it is necessary to prevent the water-soluble organic compound powder from dissolving by adjusting the pH of water. For example, an organic compound powder that is soluble only in the alkaline region can be pulverized in the presence of water in the neutral or acidic region.

The pulverized mixture of the finely divided pigment and the water-soluble organic compound is brought into contact with water whose pH is adjusted according to the solubility of the water-soluble organic compound to dissolve and remove the water-soluble organic compound. The crystallization solvent may be removed by heating the slurry after the treatment with water to remove the grinding aid from the milling mixture and evaporative removal, or by steam distillation during the treatment with water. The obtained pigment can be used as it is in a wet state or can be used in a powder state by drying. The fine pigment thus obtained has a specific surface area of 15
A pigment with a large coloring power of m ² / g or more.

In the present invention, a pigment derivative such as monophthalimidomethylcopper phthalocyanine or mono (N, N-diethyl-1,3-provandiaminoacetaminosulfonyl) quinacridone is added to the crude organic pigment in an amount of 0.1 to 20% by weight during grinding. You may add.

If necessary, a surfactant such as sodium salt of alkylbenzene sulfonate, quaternary ammonium salt, polyoxyethylene alkyl ether, etc., such as wood rosin, hydrogenated rosin, maleic acid resin, etc. ~ 50% by weight, preferably 0.5-20% by weight
You may add and grind.

(Examples) Examples will be described below. In the examples, “part” represents “part by weight”.

Example 1 50 parts of crude quinacridone and 50 parts of salicylic acid were ground in a ball mill for 40 hours. This ground mixture was slurried by adding 15 parts of sodium hydroxide to 1000 parts of water. After stirring at 80 ° C for 1 hour, filter and wash with water. The slag was slurried in 1000 parts of water, 10 parts of 98% sulfuric acid was added, and the mixture was stirred at 80 ° C for 1 hour, filtered, washed with water and dried by a conventional method to obtain 48 parts of pigment. This pigment has a specific surface area of 32 m ² / g and has a particle diameter aspect ratio of 1 to 2 when observed with an electron microscope. When it was blended with an alkyd-based paint vehicle and evaluated, it showed high tinting strength. The tinting strength was calculated from the L * value with a color machine by dispersing 10 parts of pigment in 100 parts of titanium white to make a light color.

Comparative Example 1 The crude pigment used in Example 1 was ground without using a grinding aid to obtain a pigment. The pigment obtained has a specific surface area of 7 m ^2.
The agglomerates were such that primary particles could not be discerned when observed with an electron microscope at / g, and the tinting strength was 35% inferior to the pigment obtained in Example 1.

Comparative Example 2 A pigment was obtained in the same manner as in Example 1 except that the same amount of sodium chloride was used instead of salicylic acid. The obtained pigment had a specific surface area of 12.1 m ² / g.

Example 2 65 parts of crude dioxazine violet (CI Pigment Violet 23) and 35 parts of 3-amino-6-chloro-p-toluenesulfonic acid were ground for 4 hours using a vibration mill.
The resulting ground mixture was slurried in water containing 1000 parts of potassium hydroxide and 15 parts of the mixture, stirred at 80 ° C for 1 hour, filtered, washed with water and dried to obtain 60 parts of pigment. This pigment has a specific surface area
When observed with an electron microscope at 81 m ² / g, the primary particles are spherical,
When it was added to a nitrocellulose-based vehicle for gravure ink and evaluated, it showed high tinting strength and high gloss. The gloss was measured with a gloss meter.

Comparative Example 3 Grinding was carried out in the same manner using the crude pigment used in Example 2. However, the amount of grinding aid used was 6.5 parts.
The obtained pigment had a specific surface area of 11.4 m ² / g and was an aggregate such that primary particles could not be discerned when observed with an electron microscope, and the gloss was inferior to that of the pigment obtained in Example 2.

Example 3 33 parts of crude brominated anthraquinone orange (CI Pigment Red 168), p-toluidine-m-sulfonic acid 6
7 parts were pulverized with a vibration mill at 55-60 ° C for 5 hours. The resulting ground mixture was treated in the same way as in Example 3. When this pigment was used as a colorant for polypropylene resin, it showed high tinting strength.

Example 4 The same treatment as in Example 3 was carried out using a crude copper phthalocyanine having a chlorine content of 3% (CI Pigment Blue 15: 1). When the obtained pigment was used as a coloring agent for polyethylene resin, it showed high tinting strength.

Example 5 Crude copper phthalocyanine (CI Pigment Blue 15)
20 parts and 10 parts of benzoic acid were ground for 40 hours using a ball mill. The milled mixture obtained was mixed with 1000 parts of water and 15 parts of calcium hydroxide.
The resulting mixture was slurried into a solution containing 1 part of the solution, heated and stirred at 80 ° C. for 1 hour, and filtered. Water was added to the washed slag to give a pigment concentration of about 10
% Slurry. To this slurry, 10 parts of 35% hydrochloric acid was added, filtered, washed with water and dried to obtain 19 parts of pigment. The specific surface area of the obtained pigment was 52 m ² / g, and the primary particles were spherical in the electron micrograph. When the obtained pigment was used as a colorant for an offset printing ink, an oil ink having high tinting strength, high clarity and no bronze was obtained.

Comparative Example 4 The crude pigment used in Example 5 was ground in the presence of the same amount of sodium chloride to obtain a pigment. The pigment obtained had a specific surface area of 10.6 m ² / g and was an aggregate such that primary particles could not be discerned when observed with an electron microscope. In the offset printing ink test, the pigment was less colored than the pigment obtained in Example 5. The strength was unclear, and the quality was obviously poor.

Example 6 50 parts of crude copper phthalocyanine, 50 parts of 2-amino-5-naphthol-7-sulfonic acid and 3 parts of xylene were pulverized with a ball mill at 50 to 55 ° C. for 25 hours. The obtained pulverized mixture was slurried in a solution of 1000 parts of water and 15 parts of sodium hydroxide, heated and stirred at 90 to 95 ° C for 1 hour, filtered, and washed with water. The slag was re-slurried in a solution prepared by adding 10 parts of 98% sulfuric acid to 1000 parts of water, stirred at 80 to 85 ° C for 1 hour, filtered, washed with water and dried to obtain 45 parts of pigment.

The specific surface area of this pigment was 65.4 m ² / g, and its primary particles were spherical when observed with an electron microscope, and it was high tinting strength, high clarity and bronzeless in the offset printing ink test.

Example 7 19.5 parts of crude copper phthalocyanine, 0.5 part of mono (N, N-diethyl-1,3-propanediaminosulfonyl) copper phthalocyanine, 80 parts of 3-amino-6-chloro-p-toluenesulfonic acid, 2 parts of trichloroethylene. With ball mill 40 ~
Grinded at 45 ° C for 24 hours. The same process as in Example 6 is performed 19
Some pigments are obtained. This pigment has a specific surface area of 75.1 m ² / g, and its primary particles are spherical when observed with an electron microscope. When dispersed in a vehicle for polyamide nitrocellulose-based gravure ink and evaluated, it shows high tinting strength and high gloss. It was bronzeless.

Comparative Example 5 Pulverization and purification treatment were carried out in the same manner as in Example 7 except that 3-amino-6-chloro-p-toluenesulfonic acid was not used. The obtained pigment has a specific surface area of 7.4 m ² / g and has a coloring power of 17% and a gloss of 14% as compared with the pigment obtained in Example 7.
It was inferior.

Comparative Example 6 Example 7 was repeated except that the same amount of aluminum sulfate was used instead of 3-amino-6-chloro-p-toluenesulfonic acid.
Pulverization and purification were performed in the same manner as in. The obtained pigment has a specific surface area of 56 m ² / g, and the electron micrograph shows that the primary particles are acicular, and those dispersed in the polyamide nitrocellulose gravure ink are the same as those obtained in Example 7. In comparison, the hue was reddish, the tinting strength was 10%, and the gloss was 12%.

Examples 8 to 20 and Comparative Examples 7 to 20 were carried out under the conditions shown in Table 1. The results are also shown in the table.

〔The invention's effect〕

According to the method for producing a pigment of the present invention, the organic compound can be recovered only by dissolving the organic compound powder used as the grinding aid in water and then changing the pH of the waste liquid. The recovered organic compound can be used again as a grinding aid.
For this reason, it is a very economical manufacturing method compared with the conventional manufacturing method in which the wet pulverization method is adopted and the wetting agent such as polyethylene glycol and the inorganic salt are recovered from the waste liquid.

Moreover, the quality of the obtained pigment is equivalent to that of the conventional method. In particular, according to the dry pulverization method using a conventional inorganic salt as a pulverization aid, there is a problem in terms of quality such as generation of bronze in the obtained pigment, but the pigment obtained by the production method of the present invention is There is no limitation on the use of the pigment that is excellent in quality, probably because the surface of the pulverized pigment is treated with the organic compound used as a pulverization aid.

The pigment obtained by the production method of the present invention is excellent in coloring power, gloss, etc., and therefore can be used as a coloring agent for printing ink such as oil ink and gravure ink, paint, plastic, color toner and the like.

Claims (1)

[Claims] 1. A crude pigment and 0.3 to 10 times the weight of the crude pigment and a powder of a water-soluble organic compound which is solid at room temperature are pulverized by a disperser equipped with a dispersion medium, and then a large amount of the pulverized mixture is added. A method for producing a finely divided pigment, which comprises dissolving and removing the above organic compound powder in water by bringing it into contact with water.