JPH064774B2 - Method for producing organic pigment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a method for converting a crude organic pigment into a pigment form. More specifically, the present invention provides that a crude organic pigment is dry-milled with an inorganic salt and, if necessary, an anti-agglomeration agent, reslurried in a water system if necessary, and subjected to a solvent or emulsion treatment and an acid treatment. It relates to a method for converting a crude organic pigment into a pigment form.

(Prior Art) Conventionally, a crude organic pigment obtained by synthesis in an organic solvent generally has coarse primary particles, and therefore, even if dispersed in various vehicles, it does not show a clear and low coloring power, and is used as a coloring material. Is small in value. Therefore, when used in various applications, it is necessary to make the particles finer.

When this crude organic pigment is pulverized by a ball mill or a vibration mill without using a pulverization aid, the destabilization gradually progresses. As the pulverization is performed, strong pulverization and aggregation occur, and even if dispersed in the vehicle, this Due to the strong cohesive strength, it exhibits only a very low coloring power. However, it is found in Japanese Examined Patent Publication No. 52-69435 that the crystal transition occurs and the pigment is converted when the pigment having strong pulverization and aggregation is treated in a crystallization solvent such as xylene or its aqueous emulsion. The method of converting a crude organic pigment into a pigment form by crushing it in the absence of a crushing auxiliary agent and immersing it in a crystallization solvent or an aqueous emulsion requires a large amount of solvent to be used, which causes problems of solvent recovery and fire. In addition, there are difficulties in workability.

(Problems to be Solved by the Invention) The present invention provides a method for reducing or eliminating the above-mentioned problems as a method for converting to a pigment form.

〔The invention's effect〕

(Means for Solving the Problem) The present invention relates to a crude organic pigment and 0.5 to
800% by weight of inorganic salt that generates gas by inorganic acid,
Further, the method is a method for producing an organic pigment, which comprises performing dry pulverization of an aggregating inhibitor for an organic pigment, if necessary, and then performing the following (a) and (b).

(A) Add an inorganic acid.

(B) Treat with a crystallization solvent or an aqueous emulsion of the relevant agent.

That is, a crude organic pigment, an additive that suppresses pulverization and aggregation,
As a result of accumulated research on the milling of inorganic salts, 0.5 to 800% by weight of an inorganic salt which generates gas due to the inorganic salt was added to the crude organic pigment as a grinding aid, and if necessary, 0.1 to 200% by weight of (crushing) anti-agglomeration agent is added and dry grinding is performed. After dry pulverization, the pulverized product is reslurried in water if necessary, and the crystallization solvent or its aqueous emulsion is added, and acid treatment is performed with an inorganic acid such as hydrochloric acid or sulfuric acid. The inventors have found that a pigment can be obtained and have completed the present invention.

In the present invention, the crude organic pigment is one synthesized by a known method. For example, the crude phthalocyanine is not particularly limited as a production method, but phthalic anhydride or its derivative, urea and a copper source, or phthalodithryl is used. Alternatively, a derivative thereof and a copper source are used in the presence or absence of a catalyst (for example, ammonium molybdate, titanium tetrachloride, boron, etc.) in an organic solvent at 120 to 270.
It is produced by reacting at 70 ° C., preferably 170 to 230 ° C. for 2 to 10 hours under normal pressure or increased pressure.

Crude quinacridone is not particularly limited as a production method like crude phthalocyanine. Dialkyl dianilinodihydroterephthalate is prepared from aniline and dialkyl succinate and heated in an inert solvent to cyclize to dihydroquinacdrine. Pure quinacridone is then produced by oxidation of dihydroquinacridone. Alternatively, dialkyldianilinodihydroterephthalate is oxidized to produce dialkyldianilinoterephthalate, which is hydrolyzed to produce dianilinoterephthalic acid. Further cyclization of dianilinoterephthalic acid produces crude quinacridone.

Crude anthraquinone is also not particularly limited as a production method like crude phthalocyanine and crude quinacridone.
In addition, organic pigments such as perinone type or dioxazine type can also be applied.

In the dry pulverization process, carbonates such as sodium carbonate, sodium hydrogencarbonate, calcium carbonate, etc. and inorganic salts such as sodium oxalate not only act as pulverization aids, but also when inorganic acid is added, It is considered that the salt generates a gas such as carbon dioxide gas and has the action of deflocculating the agglomerates of the crushed and agglomerated particles. However, if these salts are less than 0.5% by weight with respect to the crude organic pigment, they have little effect as a grinding aid, and a pigment having a high tinting strength cannot be obtained by this method. If it is added in excess of 800% by weight, the pulverization proceeds, but the addition of the pigment lowers the target pigment productivity, which is not necessarily economical. The preferable addition amount is 0.5 to 80% by weight,
More preferred is 1 to 50% by weight. As the inorganic salt, sodium carbonate, sodium hydrogen carbonate, calcium carbonate, and sodium oxalate, which generate carbon dioxide gas by an inorganic acid, are preferable. Inorganic salts that generate gases other than carbon dioxide can be used in some cases, but in general, there are many things that require consideration compared to carbon dioxide in the work environment.

The anticoagulant is one selected from a surfactant, a resin, a plasticizer, a metal salt of a fatty acid, etc., and examples thereof include a fatty acid salt, a higher alkyl sulphate (Na salt, amine salt),
Alkylbenzene sulfonate (Na salt), alkyl phosphate, dialkyl sulfosuccinate, alkyl amine salt, quaternary ammonium salt, alkyl pyridinium halide, alkyl pyridinium chloride,
Alkyl picorium halide, alkyl dimethyl benzyl ammonium chloride, alkyloxymethyl pyridinium chloride, polyoxyethylene alkylamine, polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl amide, sorbitan alkyl Ethyl, polyoxyethylene solderdine alkyl ester, rosin gum rosin, wood rosin, hydrogenated rosin, polymerized rosin, oxidized rosin, tall oil rosin, xylene resin, coumarone resin, ketone resin, maleic acid resin, phthalic acid resin, fatty acid (lauric acid , Myristic acid, palmitic acid, stearic acid, oleic acid, caprylic acid, caproic acid), fatty acids barium, magnesium, sub Or aluminum salts, derivatives of phthalic acid, such as liquid paraffin. Further, as the anti-agglomeration agent, an organic solvent can be used in an amount within a range that does not impair the effect of dry pulverization. These solvents include benzene, toluene, xylene, chlorobenzene,
Examples thereof include nitrobenzene, tetrahydrofuran, ethanolamine, aniline, pyridine, dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, trichloroethylene, tetrachloroethylene, cellosolve acetate and butyl acetate.

The addition amount of the aggregation preventing agent is 0.1 to 200% by weight based on the pigment. When it is added in an amount of more than 200% by weight, crushing is suppressed and it also contributes to adhesion or sticking during milling. In addition, the metal salt of fatty acid such as calcium stearate itself acts as a constitution and causes a decrease in coloring power. The preferable addition amount is 0.1 to 100% by weight, more preferably 0.5 to 30% by weight. About 20 to 80% of the organic pigments of unstable crystal form, which are finely aggregated by the addition of the aggregation inhibitor and the inorganic acid, are transformed into unstable crystals of 0 to 40%. This is the main fact of the present invention, and although it cannot be said to be sufficient due to the transition, it was found from the increase of the specific surface area and the coloring power that the deflocculation of the aggregation is progressing.
It was found that the coagulation preventing agent in this event causes a transition whether it is added during dry pulverization or after dry pulverization.

Dry crushing is carried out, for example, in a vibration mill, an attritor, a ball mill, or other crusher. Grinding temperature is 20
~ 130 ° C is preferable, and keeping the crushing temperature at 20 ° C or less is not advantageous in terms of cooling cost, and when it exceeds 130 ° C, when treated with a crystal solvent or an aqueous emulsion,
It is not desirable because it does not peptize finely. The general relationship between crushing temperature and pigment quality is that the lower the crushing temperature is, the more unstable crystals are contained.

When a crystallization solvent or an aqueous emulsion thereof is used, 0.1 to 500% by weight, preferably 0.
1 to 50% by weight, more preferably 0.5 to 30% by weight of solvent is used. As the kind, benzene, toluene, xylene, chlorobenzene, nitrobenzene, tetrahydrofuran, ethanolamine, aniline, pyridine, dimethylformamide, dimethylsulfoxide, N-methylpyrrolidone, trichloroethylene, tetrachloroethylene, cellosolve acetate, and butyl acetate are used. Further, these solvents may contain a resin, an activator, a plasticizer, or a derivative of each pigment.

The reslurrying may be performed by simply stirring at an arbitrary temperature that maintains a liquid phase, or by performing dispersion in the presence of mechanical energy such as a sand mill.

There is no difference in the quality of the added inorganic acid such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, etc., but it is desirable to add the inorganic acid so that the pH of the form is 5 or less, preferably 3 or less. When the pH exceeds 5, the peptization is difficult to proceed because the crystal transition is not sufficient. In addition, crystallization solvent treatment or aqueous emulsion treatment followed by inorganic acid gave higher coloring power.

The reslurry treated with each pigment is isolated as a pigment by filtration, drying or distillation. Of course, it is also possible to use it in a wet state as it is, without being isolated, for paints, printing inks, plastics and the like.

(Examples) Hereinafter, the present invention will be described with reference to Examples. In the examples, “part” means “part by weight” and “%” means “% by weight”.

Example 1 80 parts of crude copper phthalocyanine produced by the urea method, 15 parts of sodium carbonate and 5 parts of calcium stearate were dry-ground for 1 hour at a grinding temperature of 45 to 55 ° C. using an attritor. The obtained pulverized product is reslurried in water,
Heat and stir at 5 ° C., and add a xylene emulsion having the composition described below. Then, sulfuric acid is added until pH 1 is reached, carbon dioxide gas is generated, and acid purification is performed at the same time. Filtration, washing with water and drying gave 82 parts of pigment.

This pigment showed a 100% β-type crystal form in an X-ray diffraction pattern and had a specific surface area of 42 m ² / g. When dispersed in a rosin-modified phenolic resin varnish, this ink became a slightly reddish, vivid, and highly colored ink.

"Preparation of emulsion" The following compositions were stirred for 1 minute with a homomixer.

Xylene 1.6 parts Activator 0.1 part Water 98.3 parts Comparative Example 1 Performed in Example 1 with no addition of components other than crude phthalocyanine or with 0.1 parts of each additive. As in Example 1, the dry pulverized product and the xylene emulsion-treated product showed an extremely low tinting strength with oil ink.

Example 2 85 parts of crude quinacridone, 12 parts of calcium carbonate, and 3 parts of calcium stearate were crushed at a grinding temperature of 5 using a vibration mill.
Pulverized product obtained by continuous dry pulverization at 5 to 65 ° C. is reslurried in water and stirred with heating at 85 to 95 ° C., Example 1
Charge the same amount of xylene emulsion with the same composition as. Next, hydrochloric acid is added until the pH reaches 1, and carbon dioxide is generated, and at the same time, acid purification is performed. Filtered, washed with water, dried,
86 parts of pigment are obtained.

This pigment was an alkyd resin paint and showed high tinting strength.

Comparative Example 2 In Example 2, when 100 parts of calcium stearate was added to 1 part of crude quinacridone, the sharpness was improved, but calcium stearate became a constitution and the coloring power was lowered, and the fluidity of oil ink was improved. Became worse.

Example 3 Brominated anthraquinone orange (CI Pigme
ntRED 168) 75 parts, sodium oxalate 25
And 5 parts of hydrogenated rosin (Stevelite resin) were dry-ground using a ball mill. As the post-treatment, a xylene emulsion treatment was carried out in the same manner as in Example 1. The pigment obtained by this method showed a high tinting strength in the plastic (polyvinyl chloride) test.

Example 4 80 parts of crude copper phthalocyanine, 17 sodium hydrogen carbonate
Parts, sodium alkylbenzene sulfonate (trade name: Neoperex 205) 3 parts by dry pulverization using an attritor, and xylene emulsion (0.8 parts xylene, 0.1 parts activator, 99.1 parts water) added And add hydrochloric acid to pH 1
Added until. Filtration, washing with water and drying gave 80 parts of pigment. The rosin-modified phenolic resin type varnish showed high tinting strength.

Example 5 Perylene Red (CI Pigment Red 1
23), 17 parts of calcium carbonate and 3 parts of calcium stearate were treated in the same manner as in Example 1. The pigment obtained by this method exhibited high tinting strength in paint and plastic tests.

Example 6 Dioxazine Violet (CI Pigment
80 parts of Violet 23), 15 parts of sodium carbonate, and 5 parts of barium laurate were treated in the same manner as in Example 1. The pigment obtained by this method showed clear plastic coloring and high coloring power.

Claims (7)

[Claims] 1. A crude organic pigment and 0.5 based on the pigment.
~ 800% by weight of an inorganic salt capable of generating a gas by an inorganic acid, and optionally an anti-agglomeration agent for an organic pigment are dry-ground, and then the following (a) and (b) are carried out. Method for producing organic pigment. (A) Add an inorganic acid. (B) Treat with a crystallization solvent or an aqueous emulsion of the relevant agent. 2. The method for producing an organic pigment according to claim 1, wherein the inorganic salt is used in an amount of 1 to 50% by weight based on the pigment. 3. An anticoagulant is added to the pigment in an amount of 0.1 to 20.
The method for producing an organic pigment according to claim 1 or 2, wherein 0% by weight is used. 4. The method for producing an organic pigment according to any one of claims 1 to 3, wherein the organic pigment is one selected from a phthalocyanine type, a quinacridone type, and an anthraquinone type. 5. The method for producing an organic pigment according to claim 4, wherein the organic pigment is copper phthalocyanine. 6. An inorganic salt is one selected from sodium carbonate, sodium hydrogencarbonate calcium carbonate and sodium oxalate, and an inorganic acid is one selected from hydrochloric acid and sulfuric acid. Item 5. A method for producing an organic pigment according to any one of items 5. 7. The method for producing an organic pigment according to claim 1, wherein the aggregation preventing agent for the organic pigment is a metal salt of a fatty acid.