JP2701446B2 - Method for producing phthalocyanine crystal - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel method for producing phthalocyanine crystals. More specifically, the present invention relates to a method suitable for conversion of a new phthalocyanine crystal type.

(Prior art) Phthalocyanines are used for paints, printing inks, resin coloring,
These compounds are useful as catalysts or electronic materials. Even if the phthalocyanines are the same as a compound, there are various crystal forms, and the color tone of the pigment differs depending on the crystal form,
In addition, the characteristics of electronic materials change significantly. Therefore, it is important to control the crystal form of phthalocyanines.

As a method for this purpose, conventionally, an acid pasting method, an acid slurry method, an organic solvent treatment, a method of applying a mechanical strain force by a ball mill or the like has been adopted.

The acid pasting method is a method of dissolving phthalocyanines in 95% or more concentrated sulfuric acid and pouring it into a large amount of water to precipitate crystals. The acid slurry method uses 60 to 80% sulfuric acid to form sulfates of phthalocyanines. And a slurry is poured into a large amount of water to precipitate crystals. In addition to sulfuric acid, hydrochloric acid, nitric acid and the like can also be used, but all are inorganic acids, and the solvent to be injected is almost limited to water. The resulting crystal form is unstable or metastable. In the acid pasting method, the phthalocyanine is dissolved and then recrystallized, and in the acid slurry method, the sulfate is formed and then recrystallized.
Since phthalocyanine recrystallizes in water, removal of water-insoluble impurities cannot be expected.

Organic solvent treatment is a method in which phthalocyanine is immersed in an organic solvent such as benzene, toluene, or xylene, or is subjected to heat treatment in an organic solvent to obtain stable phthalocyanine crystals. When the unstable or metastable phthalocyanine crystal is treated with an organic solvent, the crystal transitions to a stable form, and when the stable form is treated with an organic solvent, the crystal grows in a stable form.
In each case, the phthalocyanine is considered to be partially dissolved, but is not completely solubilized and improvement in purity cannot be expected much.

The method of applying mechanical strain is a method in which phthalocyanine is put into a ball mill or a sand mill and the crystal form is converted by applying mechanical strain, and using an organic solvent, a grinding aid such as salt, sodium sulfate and the like. There is also. As the phthalocyanine obtained by such a method, X-type metal-free phthalocyanine,
Tau-type metal-free phthalocyanines and the like are known. This method has problems that the amount of treatment is small, it takes a long time until the crystal is converted, and it is difficult to always obtain a constant crystal form.

In addition, phthalocyanine does not dissolve in this method, so that an improvement in purity cannot be expected.

(Problems to be Solved by the Invention) With the above-mentioned conventional technology, a phthalocyanine crystal of an arbitrary crystal type cannot be easily obtained, and in order to obtain a desired crystal type with good purity, there are several methods described above. Or the combination had to go through a complicated process.

The present inventors have intensively studied an industrially advantageous method for producing phthalocyanine crystals, and have found that it is possible to easily convert the crystal form of phthalocyanines by treating the phthalocyanines with a solvent containing at least trifluoroacetic acid,
The present invention has been reached.

That is, an object of the present invention is to produce phthalocyanine crystals in an industrially advantageous manner. Another object of the present invention is to provide an industrially advantageous method for producing phthalocyanine crystals that can be expected to improve the purity of the phthalocyanines while converting the crystal form of the phthalocyanines.

(Means for Solving the Problems) However, the object of the present invention can be easily achieved by treating a phthalocyanine with a solvent containing at least trifluoroacetic acid.

(Operation) Hereinafter, the present invention will be described in detail.

The phthalocyanines as raw materials in the production method of the present invention refer to metal-free or metal phthalocyanines or derivatives thereof, and one kind of compound may be used alone as a raw material, or a mixture of two or more phthalocyanine compounds may be used. You may. Examples of these phthalocyanines include metal-free phthalocyanines; beryllium phthalocyanine, magnesium phthalocyanine, aluminum phthalocyanine, silicon phthalocyanine, titanium phthalocyanine, vanadium phthalocyanine, chromium phthalocyanine, manganese phthalocyanine, iron phthalocyanine, cobalt phthalocyanine, nickel phthalocyanine, copper phthalocyanine, and zinc. Phthalocyanine, gallium phthalocyanine, germanium phthalocyanine, zirconium phthalocyanine, niobium phthalocyanine, molybdenum phthalocyanine, palladium phthalocyanine, silver phthalocyanine, cadmium phthalocyanine, indium phthalocyanine, tin phthalocyanine, antimony phthalocyanine, tantalum phthalocyanine, tongue Metal phthalocyanines such as tenphthalocyanine, platinum phthalocyanine, gold phthalocyanine, mercury phthalocyanine, thallium phthalocyanine and lead phthalocyanine, and the benzene ring of these metal-free or metal phthalocyanines are substituted with a substituent such as chlorine, fluorine, nitro, cyano or sulfone. And substituted phthalocyanine derivatives. Further, the mixture of such a phthalocyanine and another compound may be subjected to treatment with a solvent containing trifluoroacetic acid. For example, when producing a phthalocyanine crystal for an electrophotographic photoreceptor, it may be subjected to a treatment together with a compound which is another component of the photoreceptor.

Such compounds include, for example, azo pigments, quinone pigments, perylene pigments, quinacridone pigments, indanthrone pigments, pigments such as perinone pigments and anthrapyrazole pigments, chloranil, tetracyanoquinodimethane, 2,4,7
Electron-withdrawing substances such as -trinitro-9-fluorenone and 2,4,5,7-tetranitro-9-fluorenone; carbazole derivatives, pyrazolines, hydrazones, oxazole compounds, stilbene compounds and triarylmethane compounds, etc. And the like.

In the present invention, the “solvent containing at least trifluoroacetic acid” may be trifluoroacetic acid alone or a mixture with one or more kinds of other solvents. Other solvents include hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, chlorobenzene and chloronaphthalene; methanol, ethanol, n-propanol, isopropanol and cyclohexanol. Alcohols such as dichloroethyl ether, isopropyl ether, n-butyl ether, 1,4-dioxane, tetrahydrofuran and methylal; ethers or acetals; ketones such as acetone, methyl ethyl ketone and cyclohexanone; acetic acid, monochloroacetic acid, dichloroacetic acid And fatty acids such as trichloroacetic acid, propionic acid and butyric acid, and phenols such as phenol, cresol and xylenol. By changing the type and ratio of these solvents, the crystal form of the obtained phthalocyanine crystal can be changed, but it is preferable to use trifluoroacetic acid in an amount that can dissolve the entire phthalocyanine to be subjected to the treatment.

The specific amount varies depending on the type of phthalocyanine, and it is generally preferable that trifluoroacetic acid 0.1 parts by weight or more is contained in the solvent with respect to 1 part by weight of the phthalocyanines to be subjected to the treatment, and further described below When the entire amount of the phthalocyanines to be treated is completely dissolved in the above manner, it is preferable that trifluoroacetic acid is contained in an amount of 2 parts by weight or more based on 1 part by weight of the phthalocyanines. Also,
When dissolved or partially dissolved or suspended using a mixture of trifluoroacetic acid and one or more kinds of other solvents, the other solvent is 100 parts by weight or less based on 1 part by weight of trifluoroacetic acid. Is preferably
When the phthalocyanine to be further treated is completely dissolved, the amount of the other solvent is preferably 10 parts by weight or less.

When dissolving the phthalocyanines in a solvent containing at least trifluoroacetic acid, it is usually dissolved at room temperature,
The solvent may be heated to increase the solubility of the phthalocyanines. The heating temperature is 72.5 which is the boiling point of trifluoroacetic acid.
It is preferable that the temperature is not higher than 0 ° C. and not higher than the boiling point of the other mixed solvent.

Phthalocyanines are preferably completely dissolved and completely recrystallized in a solvent containing trifluoroacetic acid from the viewpoint of improving the purity, but it is not always necessary to completely dissolve the raw materials of the phthalocyanines. Alternatively, the crystal form can be easily changed simply by suspending and bringing the phthalocyanines into sufficient contact with the solvent.

When the phthalocyanines are recrystallized, the method includes, for example, a method of precipitating by changing the solubility with temperature, a method of precipitating by volatilizing and concentrating the solvent, and a method of precipitating by mixing with a poor solvent. Above all, a method in which phthalocyanines are dissolved in a solvent containing at least trifluoroacetic acid and then mixed with a poor solvent and recrystallized is preferable in terms of purity, and a solution containing at least trifluoroacetic acid in which phthalocyanines are dissolved is particularly preferably water, Injection into a solvent such as an organic solvent and recrystallization yields a single crystalline phthalocyanine with high purity and is most preferable. Poor solvents that can be used during recrystallization include hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as methylene chloride, chloroform, and carbon tetrachloride; and methanol, ethanol, n-propanol, isopropanol, cyclohexanol, and the like. Alcohols; ethers or acetals such as dichloroethyl ether, isopropyl ether, n-butyl ether, 1,4-dioxane, tetrahydrofuran and methylal; ketones such as acetone, methyl ethyl ketone and cyclohexanone; acetic acid, monochloroacetic acid, dichloroacetic acid, trichlor Fatty acids such as acetic acid, propionic acid and butyric acid, water and the like can be mentioned, and these may be used as a mixture of two or more kinds.

By appropriately selecting the type, amount, ratio, temperature and the like of these solvents, various crystal forms can be obtained. In these solvents, a compound which may be mixed with the raw material phthalocyanines described in detail above may be dissolved or dispersed.

(Effects of the Invention) As described above, according to the present invention, phthalocyanine crystals of various crystal types can be easily and selectively produced by selecting the processing conditions, and in particular, when a method involving recrystallization is employed. Can be expected to improve the purity.In addition, since the solvent to be recrystallized may be water or various organic solvents, if the treatment is performed twice, water-soluble impurities and water-insoluble and organic solvent-soluble impurities can be removed, and the purity is remarkable. It can be expected to improve and provide great industrial benefits.

(Examples) Hereinafter, the present invention will be described specifically with reference to Examples.
The present invention is not limited by the following examples unless it exceeds the gist.

Example 1 5.0 g of oxytitanium phthalocyanine (hereinafter abbreviated as "TiOPc") exhibiting a powder X-ray diffraction spectrum (a crystal in which form A is slightly mixed with form B) as shown in FIG. 1 was added to 15 ml of trifluoroacetic acid and 30 ml of chloroform. Was dissolved in a mixed solvent of

This solution was poured into cyclohexanone 1 with stirring and recrystallized. After filtration, the suspension was washed in 500 ml of methanol. Further, the operation consisting of the filtration and washing with methanol was repeated twice, followed by filtration and drying at 60 ° C. under reduced pressure to obtain 3.45 g of a blue powder. When the powder X-ray diffraction spectrum of this powder was measured, the powder showed strong diffraction peaks at 7.0 °, 15.6 °, 23.6 ° and 25.7 ° at Bragg angles (2θ ± 0.2 °) as shown in FIG. It was found to be a type of TiOPc crystal.

Thus, C-type TiOPc crystals could be produced from a mixture of A-type TiOPc and B-type TiOPc.

Example 2 5.0 g of TIOPC used as a starting material in Example 1 was obtained by adding 15 ml of trifluoroacetic acid, 15 ml of phenol, and 30 ml of chloroform.
Was dissolved in a mixed solvent of This solution was poured into chloroform 1 with stirring to recrystallize. After filtration, the suspension was washed in 500 ml of chloroform. After filtering again, the suspension was washed with 500 ml of methanol. Further, the operation including the filtration and the washing with methanol was repeated twice. After filtration, the filtrate was dried under reduced pressure at 60 ° C. to obtain 3.71 g of powder.

When the powder X-ray diffraction spectrum of this powder was measured, the Bragg angle (2θ ± 0.2 °) 7.6 °, 22.6 °
Diffraction spectra having strong diffraction peaks at ゜, 25.5 ° and 28.7 ° were obtained. This is the powder X of B-type TiOPc crystal
It is a line diffraction spectrum.

Thus, from the mixture of A-type TiOPc and B-type TiOPc,
TiOPc crystals could be produced.

Example 3 5.0 g of TiOPc used as a starting material in Example 1 was mixed and dissolved in 15 ml of trifluoroacetic acid and 30 ml of chloroform, and this solution was poured into chloroform 1 at 50 ° C. with stirring to recrystallize. After filtration, the suspension was washed with 500 ml of chloroform at 50 ° C., which was again filtered and 500 ml of methanol at 60 ° C.
And washed in suspension. Filter again, methanol at 60 ° C 500m
Washed suspension in l. After filtration, vacuum drying at 60 ° C 4.4
8 g of powder were obtained.

When the powder X-ray diffraction spectrum of this powder was measured, as shown in Fig. 4, 9.4, 10.6, 13.2, 15.1, 1
Diffraction spectra having strong diffraction peaks at 5.7, 16.1, 20.8, 23.3, 26.3, and 27.1 were obtained. This is a powder X-ray diffraction pattern of Form A TiOPc.

Thus, from the mixture of A-type TiOPc and B-type TiOPc,
TiOPc crystals could be produced.

Example 4 5.0 g of TiOPc used as a starting material in Example 1 was put into a mixed solvent of 2 ml of trifluoroacetic acid and 48 ml of chloroform and sufficiently stirred. After leaving for a while, the TiOPc precipitates,
Did not dissolve. After leaving it for 45 days, the precipitate was taken out and suspended and washed with 500 ml of methanol at 60 ° C. for 3 hours. After filtration, the crystals were dried under reduced pressure at 60 ° C. to obtain 3.86 g of powder.

When the powder X-ray diffraction spectrum of this powder was measured, the Bragg angle (2θ ± 0.2 °) was 6.9 °, as shown in FIG.
Diffraction spectra having strong diffraction peaks at 15.5 °, 23.5 ° and 25.5 ° were obtained. This pattern was consistent with the powder X-ray diffraction spectrum of C-type TiOPc.

As described above, although TiOPc was not completely dissolved in the mixed solvent containing trifluoroacetic acid, C-type TiOPc crystals could be produced from a mixture of A-type and B-type TiOPc.

Example 5 5.0 g of TiOPc used as a starting material in Example 1 was dissolved in a mixed solvent of 15 ml of trifluoroacetic acid, 15 ml of phenol, and 30 ml of chloroform. Methanol 1 was added dropwise to this solution, and the dissolved TiOPc was recrystallized. 60 ° C after filtration
Was suspended and washed with 500 ml of methanol, and this filtration and washing with methanol were repeated twice. After being filtered again, it was dried at 60 ° C. under reduced pressure to obtain 4.59 g of powder.

When the powder X-ray diffraction spectrum of this powder was measured, it was as shown in FIG. This powder X-ray diffraction spectrum is different from that in FIG. 1, indicating that a TiOPc crystal having a crystal type different from that of the starting material was obtained.

Example 6 5.0 g of chloroindium phthalocyanine (X-ray powder diffraction spectrum is shown in FIG. 7) was added to 15 ml of trifluoroacetic acid,
The mixture was placed in a mixed solvent of phenol (15 ml) and chloroform (30 ml) and stirred sufficiently. After standing for a while, it was found that it was almost precipitated and only partly dissolved. This was filtered to remove the precipitate, suspended and washed with 500 ml of methanol, and then filtered. Further, this washing operation was performed twice. Drying under reduced pressure at 100 ° C. gave 4.45 g of powder.

When the powder X-ray diffraction spectrum of this powder was measured, the pattern was as shown in FIG. This pattern is different from that of FIG. 7 and indicates that a chloroindium phthalocyanine crystal having a crystal type different from that of the starting material was obtained.

Example 7 1.0 g of chloroindium phthalocyanine used as a starting material in Example 6 and 30 ml of trifluoroacetic acid were placed at 50 ° C.
To dissolve. This was poured into methanol 1 to recrystallize chloroindium phthalocyanine. This was filtered and dried under reduced pressure at 50 ° C. to obtain 0.57 g of powder.

When the powder X-ray diffraction spectrum of this powder was measured, the pattern was as shown in FIG. This pattern is different from that of FIG. 7 and indicates that a chloroindium phthalocyanine crystal having a crystal type different from that of the starting material was obtained.

Example 8 Magnesium phthalocyanine (Tokyo Kasei Reagent) 1.03 g
Was dissolved in 30 ml of trifluoroacetic acid by heating to 50 ° C., which was poured into methanol 1 to recrystallize. After filtration, the product was sprinkled and washed with methanol, and dried under reduced pressure at 60 ° C. to obtain 0.77 g of a powder.

FIG. 10 shows a powder X-ray diffraction spectrum of magnesium phthalocyanine used as a raw material, and FIG. 11 shows a powder X-ray diffraction spectrum of magnesium phthalocyanine crystal obtained in this example. The powder X-ray diffraction spectrum of the raw material magnesium phthalocyanine has strong diffraction peaks at 7.2 ° and 25.8 °, whereas the powder X-ray diffraction spectrum of the magnesium phthalocyanine crystal obtained in this example is 6.8 °, 1
It had strong diffraction peaks at 4.9 ゜ and 26.2 ゜.

In this manner, a crystalline magnesium phthalocyanine crystal different from the raw material can be produced.

Example 9 1.0 g of cobalt phthalocyanine (Tokyo Kasei Reagent) was dissolved in 30 ml of trifluoroacetic acid, and the solution was poured into methanol 1 and recrystallized. After filtration, the mixture was sprinkled and washed with methanol and then dried at 50 ° C. under reduced pressure to obtain 0.95 g of a powder.

FIG. 12 shows a powder X-ray diffraction spectrum of cobalt phthalocyanine used as a raw material, and FIG. 13 shows a powder X-ray diffraction spectrum of cobalt phthalocyanine crystal obtained in this example. The powder X-ray diffraction spectra of the raw material cobalt phthalocyanine were 7.1 °, 9.3 °, and 23.9, and had strong diffraction peaks at 26.4 ° and 30.6 °, whereas the powder X-ray diffraction spectrum of the cobalt phthalocyanine crystal obtained in this example was used. Is 9.
It had strong diffraction peaks at 0 °, 20.6 °, 21.8 °, 23.3 ° and 29.8 °.

Thus, a magnesium phthalocyanine crystal having a crystal type different from that of the raw material could be produced.

Example 10 Cobalt phthalocyanine used as a raw material in Example 9
1.0 g was dissolved in 30 ml of trifluoroacetic acid, and the solution was poured into chloroform 1 and recrystallized. After filtering this, 50
Drying under reduced pressure at ℃ gave 0.47 g of cobalt phthalocyanine.

When the powder X-ray diffraction spectrum of this cobalt phthalocyanine crystal was measured, it was found that, as shown in FIG.
A spectrum having strong diffraction peaks at ゜ and 27.4 ゜ was obtained, indicating that a cobalt phthalocyanine crystal having a crystal type different from that of the raw material cobalt phthalocyanine could be produced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a powder X-ray diffraction spectrum of oxytitanium phthalocyanine used as a raw material in Examples 1 to 5, FIG.
6 to 6 are powder X-ray diffraction spectra of oxytitanium phthalocyanine obtained in Examples 1 to 5, respectively.
7 is a powder X-ray diffraction spectrum of chloroindium phthalocyanine used as a raw material in Examples 6 and 7,
FIGS. 8 and 9 show Examples 6 and 7, respectively.
X-ray powder diffraction spectrum of the chloroindium phthalocyanine crystal obtained in Example 8, FIG. 10 is the powder X-ray diffraction spectrum of magnesium phthalocyanine used as a raw material in Example 8, and FIG. 11 is the magnesium phthalocyanine crystal obtained in Example 8. FIG. 12 is a powder X-ray diffraction spectrum of cobalt phthalocyanine used as a raw material in Examples 9 and 10, FIG. 13 and FIG.
14 is a powder X-ray diffraction spectrum of the cobalt phthalocyanine crystals obtained in Example 9 and Example 10, respectively.

Claims (1)

(57) [Claims] 1. A method for producing a phthalocyanine crystal, comprising treating a phthalocyanine with a solvent containing at least trifluoroacetic acid.