JPS62131072A - Production of copper phthalocyanine pigment - Google Patents

Abstract

PURPOSE:To obtain copper phthalocyanine pigment having a high color density, by mixing dried, ground crude copper phthalocyanine with an aq. soln. of butyl cellosolve at room temp. and heating the mixture at a specified temp. CONSTITUTION:Crude copper phthalocyanine is dried and ground. The resulting ground material is blended with an aq. soln. of 9-58% butyl cellosolve in a ratio of the ground material to butyl cellosolve of 1:1-0.05. The mixture is homogeneously mixed at room temp. and then heated at 50-100 deg.C to obtain the desired pigment. Examples of grinding aids for use in grinding crude copper phthalocyanine are water-soluble materials such as sodium chloride, sodium sulfate and calcium chloride. Butyl cellosolve is soluble in water at room temp. and well dissolved in water. However, when it is heated to 50 deg.C or above, it becomes water-insoluble. Thus, when butyl cellosolve is mixed with water and the pigment is treated at 50 deg.C or above, butyl cellosolve is separated from water, completely absorbed by the surface of the pigment and effectively promotes the crystal transition and the crystallization of the pigment.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a copper phthalocyanine pigment having a pigment form with high color density useful for paints, printing inks, colorants for plastics, and the like.

[Prior art]

Crude copper phthalocyanine obtained through ordinary synthetic reactions lacks pigmentary properties in terms of coloring power, hue, and the like.

Therefore, various methods have been used to convert crude copper phthalocyanine into useful pigment forms.

For example, there is a method in which a grinding aid is added to crude copper phthalocyanine and dry grinding is performed using a ball mill or the like.

When turning into a pigment, the ground pigment is generally turned into a pigment in an amount of organic solvent (alcohols, pheasants, etc.) equal to or more than that of the ground pigment.

Preferably, it is stirred or heated and stirred in a solvent of 3 to 10 times the amount, and is converted into a pigment in 1 to 4 hours to obtain a clear β-type copper phthalocyanine blue pigment.

[Problems to be Solved by the Invention] According to the above dry milling method, a large amount of organic solvent must be used.

Conventionally used solvents, such as butanol and quijirol, cannot be sufficiently pigmented unless an equivalent amount or more is added to the pigment, so a large amount of solvent is used.
The work environment was not good, it was dangerous, and problems with solvent recovery were major issues.

As a result of intensive research to improve the deficiencies of these conventional methods, the present inventors specifically adopted butyl cellosolve as an organic solvent. The present invention was achieved based on the finding that highly clear β-type copper phthalocyanine blue can be obtained by carrying out this process.

[Means to solve the problem]

That is, in the present invention, crude copper phthalocyanine is dry-milled, and a 9 to 58% butyl cellosolve aqueous solution is added to the ground product in an amount of 1 = 1 to 0.0 in terms of the amount of butyl cellosolve to the ground product.
5, uniformly mixed at room temperature, and then further heat-treated at 50 to 100°C.

The present invention will be explained in more detail.

The crude copper phthalocyanine used in the present invention includes copper phthalocyanine obtained by a conventionally known method,
Copper phthalocyanine, polychlorocopper phthalocyanine containing up to 14 chlorine or bromine atoms in the molecule
Examples include polychloro-bromine copper phthalocyanine containing up to 3 bromine atoms.

As the grinding aid used for grinding the above-mentioned crude copper phthalocyanine, water-soluble ones such as sodium chloride, sodium sulfate and calcium chloride can be mentioned, and these can be used singly or in combination of two or more. .

The amount of grinding aid used is 2 to 1 per crude copper phthalocyanine.
0 times by weight, preferably 5 to 7 times by weight.

The present invention is characterized by adding butyl cellosolve to dry-milled crude copper phthalocyanine and treating it with a solvent. The above-mentioned butyl cellosolve is used in combination with water, but the amount of butyl cellosolve used is the same as that of the crude copper phthalocyanine. The amount is 5 to 100% by weight, preferably 20 to 40% by weight.

When using butyl cellosolve, first, water and butyl cellosolve are mixed, and this mixture is added to the ground pigment, mixed, and heat-treated at 5 to 100°C.

When removing the copper phthalocyanine pigment after grinding and butyl cellosolve treatment, butyl cellosolve can be easily removed from the pigment by washing with washing water at 50° C. or lower, as the butyl cellosolve becomes water-soluble.

Butyl cellosolve is water-soluble at room temperature and mixes well with water, but when heated to 50°C or higher, it becomes insoluble in water.

Therefore, when butyl cellosolve is mixed with water and the pigment is treated at 50°C or higher, butyl cellosolve is separated from the water and completely adsorbed on the pigment surface, efficiently promoting the crystal transition and crystallization of the pigment.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 100 parts by weight of crude copper phthalocyanine was added to a dry attrike and pulverized for 30 minutes.

The content of the β-type crystal form of this crushed crude copper phthalocyanine was examined by X-ray diffraction, and the result was 43%.Next, 30 parts by weight of butyl cellosolve and 200 parts by weight of water were added to 100 parts by weight of the obtained crushed product. Mix for 30 minutes at room temperature. Further, the contents were heated to 90°C and stirred and mixed for 4 hours. Next, the mixture is poured into a large amount of water and heat-treated with a 2% dilute sulfuric acid aqueous solution at 80° C. to 90° C. for 50 minutes.

Next, filter, wash with water, and store the resulting pigment cake at 70-80°C.
Dry with. A clear β-type copper phthalocyanine pigment was obtained.

Example 2 100 parts by weight of crude copper phthalocyanine was added to a dry attritor and ground for 30 minutes.

The content of β-type crystals in this pulverized crude copper phthalocyanine was examined by X-ray diffraction and was found to be 43%.

Next, to 100 parts by weight of the obtained ground material, 30 parts by weight of butyl cellosolve and 200 parts by weight of a 40% aqueous sulfuric acid solution! Add 1 part of It and mix for 30 minutes at room temperature. Furthermore, the contents were heated to 90″C.
and stir and mix for 4 hours.

The mixture is then poured into a large amount of water, further filtered and washed with water, and the resulting pigment cake is dried at 70-80°C. A clear β-type copper phthalocyanine pigment was obtained.

Example 3 100 parts by weight of crude copper phthalocyanine was added to a dry attritor and pulverized for 30 minutes.

The content of β-type crystals in this pulverized crude copper phthalocyanine was examined by X-ray diffraction and was found to be 43%.

Next, 200 parts by weight of a 6% sodium hydroxide solution was added to 100 parts by weight of the obtained ground material, and the mixture was mixed for 30 minutes at room temperature. Further, the contents are heated to 80 to 90°C and stirred and mixed for 3 to 4 hours.

The mixture is then poured into a large amount of water, further filtered and washed with water, and the resulting pigment cake is dried at 70-80°C. A clear β-type copper phthalocyanine pigment was obtained.

Comparative Example 1 100 parts by weight of crude copper phthalocyanine was added to a dry attritor and pulverized for 30 minutes.

The content of β-type crystals in this pulverized crude copper phthalocyanine was examined by X-ray diffraction and was found to be 43%.

Next, 200 parts by weight of isopropyl alcohol and 200 parts by weight of water were added to 100 parts by weight of the obtained ground material, and the contents were heated to 79.5°C and stirred and mixed for 4 hours.

Next, the mixture is poured into a large amount of water and heat-treated with a 2% dilute sulfuric acid aqueous solution at 80°C to 90°C for 50 minutes. Next, it is filtered and washed with water, and the resulting pigment cake is dried at 70 to 80°C. The obtained β-type copper phthalocyanine pigment was prepared in Example 1.
Compared to the β-type copper phthalocyanine pigment obtained in Example 1, the pigment had no coloring power and the color tone was unclear.

[Effect]

In the present invention, dry-milled crude copper phthalocyanine pigment is heat-treated with a mixture of butyl cellosolve and water at 50 to 100°C. As a result, the butyl cellosolve is separated from water and completely adsorbed on the pigment surface, resulting in efficient pigment crystallization. Because it promotes transition and crystallization, it requires significantly less solvent than conventional methods, and there is no need to worry about contaminating the working environment or being dangerous.

Moreover, it is an economically superior manufacturing method as it does not require much effort to recover the solvent.

Furthermore, even when the process is carried out under strongly acidic to neutral to strongly alkaline aqueous solutions, copper phthalocyanine pigments with distinct hues and vivid coloring powers can be obtained.

Claims (1)

[Claims] Crude copper phthalocyanine is dry-milled, and a 9 to 58% butyl cellosolve aqueous solution is added to the ground product at a ratio of 1:1 to 0.0 in terms of the amount of butyl cellosolve to the ground product.
A method for producing a copper phthalocyanine pigment, which comprises mixing the pigments uniformly at room temperature and then heat-treating the pigments at 50 to 100°C.