TW202210589A - Method for manufacturing color filter pigment - Google Patents

Abstract

A method for manufacturing a color filter pigment, the method having a kneading step for kneading a mixture containing a crude pigment, an inorganic salt, and an organic solvent at a maximum shear rate exceeding 800 s-1, the crude pigment being configured from a halogenated metal phthalocyanine having zinc, iron, aluminum, magnesium, silicon, or vanadium as the central metal thereof, and the amount of electric power consumed in kneading of the mixture in the kneading step being greater than 10.0 kWh per 1 kg of the crude pigment.

Description

Manufacturing method of pigment for color filter

The present invention relates to a method for producing a pigment for color filters.

Currently, coloring compositions are used in various fields, and specific uses of the coloring compositions include printing inks, paints, colorants for resins, colorants for fibers, and color materials for information recording (Information Technology, IT). (color filter, toner, inkjet), etc. Pigments used in coloring compositions are roughly classified into pigments and dyes, and attention has been paid to organic pigments that are superior in coloring power.

Organic pigments are known to be effective as pigments for color filters. As organic pigments for color filters, phthalocyanine-based pigments are attracting attention, which can be used for green pixel portions of color filters and the like (for example, see Patent Document 1). [Prior Art Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2018/043548 Manual

[The problem to be solved by the invention] The objective of this invention is to provide the manufacturing method of the pigment for color filters which can improve the brightness|luminance of a pixel part. [Means of Solving Problems]

The organic compound constituting the organic pigment aggregates with each other after synthesis, and exists in the state of an aggregate called a crude product (Crude). Therefore, it is usually impossible to use the synthesized organic compound as a pigment as it is, and to perform a pigmentation step for adjusting the particle size. The aggregate (crude product) of the organic compound pigmented in the pigmentation step is called a crude pigment, and a fine organic pigment is obtained by pulverizing the crude pigment by kneading or the like.

Pigmentation of a crude pigment for producing an organic pigment is usually performed by kneading a mixture containing a crude pigment, an inorganic salt, and an organic solvent, but during kneading, crystallization and refinement of the crude pigment are simultaneously performed. If the energy (electricity consumed for kneading) input into the kneading of the mixture is too large, the above-mentioned crystallization is dominant, so in order to obtain fine pigments, it is necessary to keep the input energy not too large (for example, per 1 kg of coarse pigments) power consumption below 8.0 kWh).

The present inventors have paid attention to the fact that the phthalocyanine-based pigment is a pigment that can improve the brightness of the pixel portion, but is also a pigment that is easy to crystallize. crystallization, even when kneading is carried out with a larger energy than usual, the refinement of the coarse pigment is dominant, and the phthalocyanine-based pigment can be further refined. The concept of color filter pigments for brightness. The present inventors have completed the present invention as a result of diligent research based on the above-mentioned concept.

That is, one aspect of the present invention relates to a method for producing a pigment for a color filter, which includes a kneading step of kneading a mixture containing a crude pigment, an inorganic salt and an organic solvent at a maximum shear rate exceeding 800 s ⁻¹ , the crude pigment contains halogenated metal phthalocyanine with zinc, iron, aluminum, magnesium, silicon or vanadium as the central metal, and the electricity consumed by the mixing of the mixture in the mixing step is more than 10.0 kWh per 1 kg of crude pigment.

According to the manufacturing method of the said aspect, the pigment for color filters which can improve the brightness|luminance of a pixel part can be obtained.

Halogenated metal phthalocyanines are compounds in which at least a part of hydrogen atoms on the aromatic rings of metal phthalocyanines are halogenated, and the phthalocyanine rings tend to have a distorted structure due to halogenation of the aromatic rings, and thus tend not to be easily crystallized. Therefore, it is presumed that by using a crude pigment containing a halogenated metal phthalocyanine as the crude pigment, even when the energy input at the time of kneading (the amount of electricity consumed by the kneading) is increased, crystallization is unlikely to proceed. On the other hand, although the research results of the present inventors are clear, when the energy input during kneading (the amount of electricity consumed by kneading) is large, even if the crude pigment containing the halogenated metal phthalocyanine is used, when kneading If the maximum shear rate is 800 s ^-1 or less, the agglomeration of coarse pigments will also occur. Therefore, the maximum shear rate during kneading needs to be greater than 800 s ^-1 . By making the maximum shear rate at the time of kneading more than 800 s ^-1 , it is possible to maintain a state in which aggregation of the coarse pigment is unlikely to occur during the kneading, and it is presumed that the refinement of the coarse pigment is dominant.

In one aspect, the pH of the crude pigment may be less than 5. In this case, the central metal of the crude pigment may be zinc, iron or magnesium. Moreover, in this case, the manufacturing method of the pigment for color filters may further include the washing|cleaning process of washing|cleaning the kneaded mixture obtained in the kneading process with the aqueous solution of pH more than 8 at 25 degreeC.

In one aspect, the average number of halogen atoms in one molecule of the halogenated metal phthalocyanine in the crude pigment may be 9 or more.

In one aspect, during the kneading step, the mixture may be kneaded at a temperature below 110°C.

In one aspect, the amount of the inorganic salt used in the kneading step may be 30 parts by mass or more relative to 1 part by mass of the crude pigment. [Effect of invention]

ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the pigment for color filters which can improve the brightness|luminance of a pixel part can be provided.

Hereinafter, preferred embodiments of the present invention will be described. However, this invention is not limited at all by the following embodiment.

The manufacturing method of the pigment for color filters of one embodiment includes, for example, a first step of preparing a rough pigment and a second step of pigmenting the rough pigment.

The crude pigment prepared in the first step contains a halogenated metal phthalocyanine (hereinafter, also simply referred to as "halogenated metal phthalocyanine") having zinc, iron, aluminum, magnesium, silicon or vanadium as the central metal. That is, the crude pigment is selected from the group consisting of halogenated zinc phthalocyanine crude pigment, halogenated iron phthalocyanine crude pigment, halogenated aluminum phthalocyanine crude pigment, halogenated magnesium phthalocyanine crude pigment, halogenated silicon phthalocyanine crude pigment and halogenated vanadium phthalocyanine crude pigment The halogenated metal phthalocyanine crude pigment in the group, the pigment for color filters manufactured by the manufacturing method of this embodiment is selected from halogenated zinc phthalocyanine pigment, halogenated iron phthalocyanine pigment, halogenated aluminum phthalocyanine pigment, halogenated Halogenated metal phthalocyanine pigments in the group consisting of magnesium phthalocyanine pigments, halogenated silicon phthalocyanine pigments, and halogenated vanadium phthalocyanine pigments.

The crude pigment may be obtained, for example, by precipitating the halogenated metal phthalocyanine immediately after synthesis (for example, an aggregate of halogenated metal phthalocyanine). The crude pigment may contain one type of halogenated metal phthalocyanine, or may contain a plurality of halogenated metal phthalocyanines having different numbers of halogen atoms.

The halogenated metal phthalocyanine has, for example, a structure represented by the following formula (1).

[hua 1]

In formula (1), X ¹ to X ¹⁶ each independently represent a hydrogen atom or a halogen atom. M is the central metal, and represents Zn (zinc), Fe (iron), Al (aluminum), Mg (magnesium), Si (silicon), or V (vanadium). Z is an axial ligand bonded to the central metal (M), and represents a halogen atom, an oxygen atom, a hydroxyl group, a sulfonic acid group, -OP(=O)R ¹ R ² [R ¹ and R ² each independently represent A group represented by a hydrogen atom, a hydroxyl group, an optionally substituted alkyl group, an optionally substituted aryl group, an optionally substituted alkoxy group, or an optionally substituted aryloxy group], -OC(=O) R ³ [R ³ represents a group represented by a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted aryl group, or an optionally substituted heterocyclic group], -OS A group represented by (=O) ₂ R ⁴ [R ⁴ represents a hydroxyl group, an optionally substituted alkyl group, an optionally substituted aryl group, or an optionally substituted heterocyclic group]. m represents the number of Z bonded to M, and is an integer of 0 to 2.

Examples of the alkyl group in R ¹ to R ⁴ include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, neopentyl, n-hexyl, n-octyl, Linear or branched alkyl groups such as stearyl, 2-ethylhexyl, etc. Examples of the substituent of the substituted alkyl group include halogen atoms such as a chlorine atom, a fluorine atom, and a bromine atom; an alkoxy group such as a methoxy group; an aryl group such as a phenyl group and a tolyl group; a nitro group and the like. There may be multiple substituents. Examples of the substituted alkyl group include trichloromethyl, trifluoromethyl, 2,2,2-trifluoroethyl, 2,2-dibromoethyl, 2-ethoxyethyl, 2-Butoxyethyl, 2-nitropropyl, benzyl, 4-methylbenzyl, 4-tert-butylbenzyl, 4-methoxybenzyl, 4-nitrobenzyl, 2 , 4-Dichlorobenzyl and so on.

Examples of the aryl group in R ¹ to R ⁴ include monocyclic aromatic hydrocarbon groups such as phenyl and p-tolyl; condensed aromatic hydrocarbon groups such as naphthyl and anthracenyl. Examples of the substituent of the substituted aryl group include halogen atoms such as a chlorine atom, a fluorine atom, and a bromine atom; an alkoxy group; an amino group; a nitro group and the like. There may be multiple substituents. Examples of the substituted aryl group include p-bromophenyl, p-nitrophenyl, p-methoxyphenyl, 2,4-dichlorophenyl, pentafluorophenyl, and 2-dimethylamine. phenyl, 2-methyl-4-chlorophenyl, 4-methoxy-1-naphthyl, 6-methyl-2-naphthyl, 4,5,8-trichloro-2-naphthyl, Anthraquinone, etc.

Examples of the alkoxy groups in R ¹ and R ² include methoxy, ethoxy, propoxy, isopropoxy, n-butoxy, isobutoxy, tert-butoxy, neopentyl Linear or branched alkoxy groups such as oxy, 2,3-dimethyl-3-pentyloxy, n-hexyloxy, n-octyloxy, stearyloxy, 2-ethylhexyloxy, etc. Examples of the substituent of the substituted alkoxy group include halogen atoms such as a chlorine atom, a fluorine atom, and a bromine atom; an alkoxy group; an aryl group such as a phenyl group and a tolyl group; a nitro group and the like. There may be multiple substituents. Examples of the substituted alkoxy group include trichloromethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, 2,2,3,3-tetrafluoropropoxy , 2,2-di-trifluoromethylpropoxy, 2-ethoxyethoxy, 2-butoxyethoxy, 2-nitropropoxy, benzyloxy and the like.

Examples of the aryloxy groups in R ¹ and R ² include aryloxy groups including a monocyclic aromatic hydrocarbon group such as phenoxy and p-methylphenoxy; and aryloxy groups including a condensed aromatic hydrocarbon group such as naphthoxy and anthraceneoxy aryloxy, etc. Examples of the substituent of the substituted aryloxy group include halogen atoms such as a chlorine atom, a fluorine atom, and a bromine atom; an alkyl group; an alkoxy group; an amino group; a nitro group and the like. There may be multiple substituents. Examples of the substituted aryloxy group include p-nitrophenoxy, p-methoxyphenoxy, 2,4-dichlorophenoxy, pentafluorophenoxy, 2-methyl-4 - Chlorophenoxy, etc.

Examples of the cycloalkyl group in R ³ include monocyclic aliphatic hydrocarbon groups such as cyclopentyl, cyclohexyl, 2,5-dimethylcyclopentyl, and 4-tert-butylcyclohexyl; bornyl, adamantane, etc. Condensation of aliphatic hydrocarbon groups and the like. Examples of the substituent of the substituted cycloalkyl group include halogen atoms such as a chlorine atom, a fluorine atom, and a bromine atom; an alkyl group; an alkoxy group; a hydroxyl group; an amino group; a nitro group and the like. There may be multiple substituents. As a cycloalkyl group which has a substituent, a 2, 5- dichlorocyclopentyl group, a 4-hydroxycyclohexyl group, etc. are mentioned, for example.

Examples of heterocyclic groups in R ³ and R ⁴ include aliphatic heterocyclic groups such as pyridyl, pyrazinyl, piperidinyl, pyranyl, morpholinyl, and acridine groups, and aromatic heterocyclic groups. . Examples of the substituent of the substituted heterocyclic group include halogen atoms such as a chlorine atom, a fluorine atom, and a bromine atom; an alkyl group; an alkoxy group; a hydroxyl group; an amino group; a nitro group and the like. There may be multiple substituents. As a heterocyclic group which has a substituent, 3-methylpyridyl, N-methylpiperidyl, N-methylpyrrolyl etc. are mentioned, for example.

As a halogen atom represented by X1 ^{- X16} , a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned. From the viewpoint of obtaining more excellent brightness, at least one of X ¹ to X ¹⁶ is preferably a bromine atom or a chlorine atom, more preferably a bromine atom. X ¹ to X ¹⁶ may all be chlorine atoms or bromine atoms.

When M is Al, Si, or V, more excellent brightness is easily obtained. The reason for this is presumed that stacking of phthalocyanine rings due to intermolecular interaction is not easily generated by the axial ligand (Z) bonded to the central metal (M), and the crude pigment has lower crystallinity. In addition, when M is Zn, Fe, or Mg, when a compound that reacts with water to generate an acid is used in synthesizing a halogenated metal phthalocyanine, it is easy to obtain more excellent brightness. The reason for this is presumed as follows. That is, in a halogenated metal phthalocyanine having a distorted structure due to halogenation, when M is Zn, Fe, or Mg, it is different from when M is Cu (copper), Ni (nickel), Co (cobalt), or the like. In comparison, the distance between the central metal (M) of the phthalocyanine ring and the nitrogen atom on the isoindoline unit is longer, and a large hole is formed around the central metal (M). Therefore, in the case of protonating the nitrogen atom on the isoindoline unit under acidic conditions, when M is Zn, Fe or Mg, and M is Cu (copper), Ni (nickel), Co (cobalt) The counter anion (for example, a halide ion such as chloride ion) is more likely to be stabilized in a state close to the central metal than in the case of the like. Due to the presence of the counter anion, stacking of phthalocyanine rings due to intermolecular interaction is unlikely to occur, whereby the crude pigment has lower crystallinity, so it is presumed that more excellent brightness can be obtained.

m varies according to the valence of M. When the valence of M is 2, that is, when M is Zn, Fe, or Mg, m is 0. When the valence of M is 3, that is, when M is Al, m is 1. In this case, Z is a halogen atom, a hydroxyl group, a sulfonic acid group, a group represented by -OP(=O)R ¹ R ² , a group represented by -OC(=O)R ³ , -OS(=O) A group represented by ₂ R ⁴ . When the valence of M is 4, that is, when M is Si or V, m is 1 or 2. When the valence of M is 4 and m is 1, Z is an oxygen atom, and M and Z (oxygen atom) are bonded to each other by a double bond. When the valence of M is 4 and m is 2, Z is a halogen atom, a hydroxyl group, a sulfonic acid group, a group represented by -OP(=O)R ¹ R ² , a group represented by -OC(=O)R ³ The group represented by the group represented by -OS(=O) ₂ R ⁴ may be the same as or different from each other. As a halogen atom represented by Z, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned.

The average number of halogen atoms in one molecule of the halogenated metal phthalocyanine (for example, the compound represented by formula (1)) in the crude pigment is 0.1 or more and 16 or less. The average number of halogen atoms may be less than nine, and preferably nine or more. When the average number of halogen atoms is 9 or more, there are 5 or more halogen atoms at the α-position of the phthalocyanine ring (in the compound represented by the formula (1), X ¹ , X ⁴ , X ⁵ , X ⁸ , X ^9. At least five of X ¹² , X ¹³ and X ¹⁶ become halogen atoms), and at least two halogen atoms exist adjacent to each other, so that the phthalocyanine ring is likely to form a distorted structure and the crystallinity of the crude pigment becomes lower. tendency. Therefore, when the average number of halogen atoms is 9 or more, the effect of the present invention tends to be remarkably obtained. From this viewpoint, the average number of halogen atoms may be 10 or more, 11 or more, 12 or more, 13 or more, 14 or more, or 15 or more. In addition, when a halogenated metal phthalocyanine contains a halogen atom in an axial ligand, the number of the said halogen atom means the number of the halogen atom which replaces the hydrogen atom of an aromatic ring.

The average number of bromine atoms in one molecule of the halogenated metal phthalocyanine (for example, the compound represented by formula (1)) in the crude pigment may be less than 13, and may be 13 or more.

When the average number of bromine atoms is less than 13, the average number of bromine atoms may be 0.1 or more, 6 or more, or 8 or more. In addition, the average number of bromine atoms may be 12 or less or 11 or less. The upper limit value and the lower limit value can be arbitrarily combined. For example, the average number of bromine atoms may be 0.1 or more and less than 13, 8 to 12, or 8 to 11. In addition, in the same description below, the upper limit value and the lower limit value described individually may be combined arbitrarily.

When the average number of bromine atoms is less than 13, the average number of chlorine atoms in one molecule of the halogenated metal phthalocyanine (for example, the compound represented by formula (1)) in the crude pigment may be 5 or less and 3 or less. , 2.5 or less or less than 2. The average number of chlorine atoms may be 0.1 or more, 0.3 or more, 0.6 or more, 0.8 or more, 1 or more, 1.3 or more, or 2 or more.

When the average number of bromine atoms is less than 13, the average number of halogen atoms in one molecule of the halogenated metal phthalocyanine (for example, the compound represented by formula (1)) in the crude pigment may be 14 or less and 13 or less. , less than 13 or less than 12. The average number of halogen atoms may be 8 or more, 9 or more, or 10 or more.

When the average number of bromine atoms is 13 or more, the average number of bromine atoms may be 15 or less. The average number of bromine atoms may be 14 or more.

When the average number of bromine atoms is 13 or more, the average number of chlorine atoms in one molecule of the halogenated metal phthalocyanine (for example, the compound represented by formula (1)) in the crude pigment may be 0.1 or more or 1 or more. . The average number of chlorine atoms may be three or less or less than two.

When the average number of bromine atoms is 13 or more, the average number of halogen atoms in one molecule of the halogenated metal phthalocyanine (for example, the compound represented by formula (1)) in the crude pigment may be 13 or more, 14 or more or more than 15. The average number of halogen atoms may be 15 or less.

The number of the halogen atoms (for example, the number of bromine atoms and the number of chlorine atoms) is determined by, for example, a crude value using a matrix-assisted laser desorption free time-of-flight mass spectrometer (JMS-S3000 manufactured by Nippon Electronics Co., Ltd., etc.). Pigment quality analysis to be specific. Specifically, the number of each halogen atom can be calculated as a relative value per metal atom from the mass ratio of the metal atom (the metal atom serving as the central metal of the halogenated metal phthalocyanine) and each halogen atom in the crude pigment.

The first step includes, for example, synthesizing halogenated metal phthalocyanines with zinc, iron, aluminum, magnesium, silicon or vanadium as the central metal by known production methods such as the chlorosulfonic acid method, the halogenated phthalonitrile method, and the melting method. and the step of precipitating the synthesized halogenated metal phthalocyanine to obtain a crude pigment (halogenated metal phthalocyanine crude pigment). The step of synthesizing a halogenated metal phthalocyanine may be, for example, a step of synthesizing a halogenated metal phthalocyanine using a compound that reacts with water to generate an acid. As a method of synthesizing a halogenated metal phthalocyanine using a compound which reacts with water to generate an acid, for example, a chlorosulfonic acid method, a melting method, etc. are mentioned.

Examples of the chlorosulfonic acid method include a method in which a metal phthalocyanine (eg, zinc phthalocyanine) is dissolved in a sulfur oxide-based solvent such as chlorosulfonic acid, and chlorine gas and bromine are charged therein for halogenation. The reaction at this time is carried out, for example, at a temperature of 20° C. to 120° C. for 3 hours to 20 hours. In the chlorosulfonic acid method, the sulfur oxide-based solvent such as chlorosulfonic acid is a compound that reacts with water to generate an acid. For example, chlorosulfonic acid reacts with water to produce hydrochloric acid and sulfuric acid.

Examples of the halogenated phthalonitrile method include, for example, a method that preferably uses phthalic acid or phthalodinitrile in which a part or all of the hydrogen atoms of the aromatic ring are substituted with halogen atoms such as bromine and chlorine, and phthalonitrile which becomes the central metal. The corresponding halogenated metal phthalocyanine is synthesized using a metal or a salt of the metal as a starting material. In this case, catalysts, such as ammonium molybdate, can also be used as needed. The reaction at this time is carried out, for example, at a temperature of 100° C. to 300° C. for 7 hours to 35 hours.

Examples of the melting method include a method of melting aluminum halides such as aluminum chloride and aluminum bromide, titanium halides such as titanium tetrachloride, and alkali metal halides or alkaline earth metal halides such as sodium chloride and sodium bromide (hereinafter, It is called "alkaline (earth) metal halide"), thionine chloride and other compounds that become solvents during halogenation. One or two or more kinds of compounds are melted at about 10°C to 170°C. Metal phthalocyanines such as zinc phthalocyanines undergo halogenation. In the melting method, the compounds that become a solvent during halogenation, such as aluminum halide, titanium halide, alkali (earth) metal halide, and thionite chloride, are compounds that react with water to generate acid. For example, aluminum chloride reacts with water to produce hydrochloric acid.

The preferred aluminum halide is aluminum chloride. The amount of aluminum halide added in the method using aluminum halide is usually 3 times mol or more, preferably 10 to 20 times mol, relative to metal phthalocyanine (eg, zinc phthalocyanine).

Aluminum halide can be used alone, but if an alkali (earth) metal halide is used in combination with aluminum halide, the melting temperature can be further lowered, which is advantageous in operation. The preferred alkali (earth) metal halide is sodium chloride. The amount of the alkali (earth) metal halide to be added is preferably 1 to 15 parts by mass relative to 10 parts by mass of the aluminum halide within the range where the molten salt is formed.

As the halogenating agent, chlorine gas, sulfonyl chloride, bromine, etc. may be mentioned.

The halogenation temperature is preferably 10°C to 170°C, more preferably 30°C to 140°C. Furthermore, in order to speed up the reaction rate, you may pressurize. The reaction time may be 5 hours to 100 hours, preferably 30 hours to 45 hours.

The combined use of two or more kinds of the compounds in the melting method can be arbitrarily controlled by adjusting the ratio of chloride, bromide, and iodide in the molten salt, or by changing the introduction amount of chlorine, bromine, iodine, etc., and the reaction time. The content ratio of the halogenated metal phthalocyanine composed of a specific halogen atom in the generated halogenated metal phthalocyanine is preferable. In addition, according to the melting method, the decomposition of the raw material in the reaction is small, the yield based on the raw material is more excellent, and the reaction can be carried out in an inexpensive apparatus without using a strong acid.

In the present embodiment, a halogenated metal phthalocyanine having a halogen atom composition different from that of a conventional halogenated metal phthalocyanine can be obtained by optimizing the method of charging the raw materials, the catalyst species and their usage amounts, the reaction temperature, and the reaction time.

In any of the above-mentioned methods, in the reaction solution obtained after the completion of the reaction, the halogenated metal phthalocyanine is in a state of being dissolved in the reaction solution. After the completion of the reaction, the obtained mixture (reaction solution) is put into an acidic aqueous solution such as water and hydrochloric acid, or an alkaline aqueous solution such as an aqueous sodium hydroxide solution to precipitate (precipitate) the generated halogenated metal phthalocyanine. At this time, in the case of using the compound that reacts with water to generate an acid, if an acidic aqueous solution such as water or hydrochloric acid is used, an acid such as hydrochloric acid and sulfuric acid is generated, and the acid is encapsulated in the precipitate, so that the acid remains in the crude in the paint. On the other hand, in the case of using an alkaline aqueous solution, since the generation of an acid can be suppressed, the inclusion of the acid in the precipitate can be suppressed, and the residual of the acid in the crude pigment can be suppressed. When the acid is contained in the crude pigment, the aggregation of the particles due to the acid is promoted during pigmentation, and it is considered that the miniaturization of the pigment particles is hindered. However, by reducing the acid contained in the crude pigment by the above-mentioned method, the Finer pigment particles.

The first step may further include a post-processing step of post-processing the precipitate after the precipitation step.

For example, the first step may further include a step of filtering the precipitate (first post-processing step). The first post-processing step may be a step of filtering and washing the precipitate, or a step of filtering, washing and drying the precipitate. Washing can be performed using an aqueous solvent such as water, sodium hydrogensulfate water, sodium hydrogencarbonate water, and sodium hydroxide water, for example. In washing, organic solvents such as acetone, toluene, methanol, ethanol, and dimethylformamide may be used as necessary. For example, after washing with an aqueous solvent, washing with an organic solvent may be performed. Washing can be repeated several times (eg, 2 to 5 times). Specifically, it is preferable to perform washing until the pH of the filtrate is equal to the pH of the water used for washing (for example, the difference between the two is 0.2 or less).

For example, the first step may further include a step of dry grinding the precipitate (second post-processing step). Dry grinding can be performed, for example, in a pulverizer such as an attritor, a ball mill, a vibration mill, and a vibration ball mill. Dry pulverization can be performed while heating (for example, heating so that the temperature inside the pulverizer may be 40° C. to 200° C.). After dry grinding, washing with water can be performed. The amount of the acid contained in the crude pigment can be further reduced by performing washing with water after dry grinding (especially after dry grinding with an attritor). The washing may be any of water washing (washing with water below 40° C.) and hot water washing (washing with water at 40° C. or higher). Washing is preferably performed until the pH of the filtrate is equal to the pH of the water used for washing in the same manner as in the first post-processing step (for example, the difference between the two is 0.2 or less). Furthermore, during or before washing with water, a treatment for improving the wettability of the precipitate (for example, a treatment for bringing the precipitate into contact with a water-soluble organic solvent such as methanol) may be performed. Dry grinding and washing can be repeated several times.

The first step may further include, for example, a step of kneading the precipitate with water (third post-processing step). By carrying out the third post-treatment step, the amount of acid encapsulated in the crude pigment can be further reduced. Kneading can be performed using, for example, a kneader, a kneader, or the like. Kneading can be performed while heating. For example, the temperature of the water can be set to 40°C or higher. Inorganic salts can be added to water. At this time, by making at least a part of the inorganic salt exist in a solid state, the force applied during kneading can be increased. During kneading, an organic solvent (for example, an organic solvent that can be used in the second step described later) can be used, but the amount of the organic solvent used is preferably less than the amount of water, and more preferably no organic solvent is used. After kneading, washing can be carried out in the same manner as in the first post-processing step. Mixing and washing can be repeated several times.

For example, the first step may further include a step of heating (eg, boiling) the precipitate in water (fourth post-processing step). By performing the fourth post-processing step, the amount of acid encapsulated in the crude pigment can be further reduced. The heating temperature in water may be, for example, 40° C. or higher and the boiling point or less, and the heating time may be, for example, 1 minute to 300 minutes. An organic solvent (for example, an organic solvent that can be used in the second step described later) may be mixed in water, and the mixed amount of the organic solvent is preferably 20 parts by mass or less relative to 100 parts by mass of water. In the fourth post-processing step, from the viewpoint of further removing the acid, the precipitate may be heated in water and then washed, or the precipitate may be heated in water and then washed, and the heating and washing in water may be repeated. The repetition is performed more than once (preferably more than twice). Washing can be performed in the same way as the first post-processing step.

In the present embodiment, two or more of the first to fourth post-processing steps described above may be implemented. When implementing two or more steps among the first to fourth post-processing steps, the order is not particularly limited.

A crude pigment can be obtained by the first step. As described above, in the present embodiment, the precipitate obtained in the first step can be directly used as a crude pigment, or the precipitate can be subjected to other methods. The post-processing step (at least one of the first post-processing step to the fourth post-processing step) is obtained as a crude pigment.

The arithmetic standard deviation of the particle size distribution of the coarse pigment is, for example, 15 nm or more. The arithmetic standard deviation of the particle size distribution of the coarse pigment is, for example, 1500 nm or less. When the arithmetic standard deviation of the particle size distribution of the coarse pigment is in such a range, finer pigment particles can be easily obtained. The arithmetic standard deviation of the particle size distribution of the coarse pigment can be measured using a dynamic light scattering type particle size distribution measuring apparatus, and specifically, can be measured by the following method and conditions. ＜Method＞ Using zirconium beads of 0.3 mm to 0.4 mm, 2.48 g of crude pigment was mixed with 1.24 g of BYK-LPN6919 manufactured by BYK-Chemie, and 1.86 g of Dynamo using a paint shaker manufactured by Toyo Seiki Co., Ltd. Unidic ZL-295 manufactured by DIC Co., Ltd. and 10.92 g of propylene glycol monomethyl ether acetate were dispersed together for 2 hours to obtain a dispersion. 0.02 g of the dispersion from which the zirconium beads were removed with a nylon sieve was diluted with 20 g of propylene glycol monomethyl ether acetate to obtain a dispersion for particle size distribution measurement. <Condition> ‧Measuring device: Dynamic light scattering particle size distribution measuring device LB-550 (manufactured by Horiba Manufacturing Co., Ltd.) ‧Measurement temperature: 25℃ ‧Measurement sample: dispersion for particle size distribution measurement ‧Data analysis conditions: particle diameter reference scattered light intensity, dispersion medium refractive index 1.402

Coarse pigments may contain acids. The inclusion of acid in the crude pigment can be confirmed by mixing 5 g of the crude pigment with 5 g of methanol, and further mixing with 100 ml of ion-exchanged water, and heating the obtained mixture for 5 minutes to set it to be. In the boiling state, the mixture was heated for 5 minutes and maintained in the boiling state. The heated mixture was left to cool to 30° C. or lower, and the total amount of the mixture was adjusted to 100 ml with ion-exchanged water. pH at °C. In this specification, the pH of the filtrate measured by the said method is defined as "pH of a crude pigment". When the pH of the crude pigment is less than 5, the effect of the present invention tends to be remarkably obtained. In particular, when the central metal of the halogenated metal phthalocyanine constituting the crude pigment is zinc, iron, or magnesium, and when acid is contained in the crude pigment, the crystallinity tends to be further lowered, and the present invention can be further remarkably obtained. effect tendencies. From this viewpoint, the pH of the crude pigment may be 4.5 or less or 3.5 or less. The pH of the filtrate may be, for example, 2.0 or more.

The second step includes a kneading step of kneading the mixture comprising the crude pigment, inorganic salt and organic solvent prepared in the first step at a maximum shear rate exceeding 800 s ⁻¹ . In the kneading step, the coarse pigment is pulverized and made fine by kneading the mixture using a kneading device. As the kneading device, for example, a kneader, a mix muller, a planetary mixer, a continuous uniaxial kneader, a flusher, or the like can be used. The kneading device may be an open type or a closed type, but if it is a closed type, volatilization of the organic solvent can be suppressed, and the kneading time can be further extended. In addition, the kneader may be a tangential type or a meshing type. If the kneader is a tangential type, the kneading can be efficiently performed even when the viscosity of the kneaded product is high.

FIG. 1 is a schematic cross-sectional view showing the internal structure of a kneading apparatus used in a production method according to an embodiment. The kneading device 10 shown in FIG. 1 is a double-arm type kneader, and includes a kneading chamber 11 and a pair of blades 12 provided in the kneading chamber 11 . In the kneading step, the mixture is put into the kneading chamber 11, and then the pair of blades 12 are rotated by a motor. In the kneading device 10 , a clearance C1 exists between the inner wall surface 11 a of the kneading chamber 11 and the blades 12 , and the pair of blades 12 rotate in opposite directions (arrow directions shown in FIG. 1 ) around the rotation axis L1 , thereby applying shear stress to the mixture passing through the gap C1, thereby refining the coarse pigment. Usually, a pair of vanes 12 have the same shape as each other.

FIG. 2 is a schematic plan view showing the internal structure of a kneading device used in another embodiment, and FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2 . The kneading device 20 shown in FIGS. 2 and 3 is a kneading mill, and includes a kneading chamber 21 having a circular bottom surface 21a, a pair of muller wheels 22 provided in the kneading chamber 21, a column portion 23, The connecting portion 24 and the pressurizing spring 25 . The roller 22 is connected to the column portion 23 by the connection portion 24 . The column portion 23 extends vertically from the center of the bottom surface 21a, and is rotatable around the rotation axis L2 by a motor. In the kneading step, after disposing the mixture on the bottom surface 21 a of the kneading chamber 21 , the pair of rollers 22 revolves around the column portion 23 by rotating the column portion 23 . In the kneading device 20, a gap (clearance) C2 exists between the bottom surface 21a of the kneading chamber 21 and the rollers 22, and a load from the vertical direction is applied by the self-weight of the rollers 22 and/or the compression spring 25. Then, the roller 22 revolves and rotates by being in contact with the mixture passing through the gap C2, whereby the kneading, smearing and spatulate functions act on the mixture, thereby making the coarse pigment finer . Typically, a pair of rollers 22 have the same shape as each other.

When the maximum shear rate during kneading exceeds 800 s ^-1 , it may be 1500 s ^-1 or more or 2500 s ^-1 from the viewpoint that the aggregation of the coarse pigment during kneading can be further suppressed and the coarse pigment can be further refined. above. From the viewpoint of preventing breakage of pigment particles, the maximum shear rate may be 5000 s ⁻¹ or less. From these viewpoints, the maximum shear rate may exceed 800 s ⁻¹ and be 5000 s ⁻¹ or less, 1500 s ⁻¹ to 5000 s ⁻¹ , or 2500 s ⁻¹ to 5000 s ⁻¹ . Here, the "maximum shear rate" refers to the shear rate at the portion where the shear rate of the kneaded product becomes the largest in the kneading device. When the moving speed of the kneaded material (the distance moved per unit time) is v, and the width of the part where the kneaded material passes at the moving speed v is set as h, the "shearing speed" can be represented by v/h. For example, when the kneading device 10 shown in FIG. 1 is used, the shearing speed in the gap C1 can be determined by setting the moving speed of the kneaded material when passing through the gap C1 as v, and the width of the gap C1 as h ask for. In addition, for example, when the kneading device 20 shown in FIG. 2 is used, the shearing speed in the gap C2 can be made by setting the moving speed of the kneaded product when passing through the gap C2 as v, and the width of the gap C2 as h to find out. Usually, the movement speed (distance per unit time) of the kneaded product is the highest at the position where the gap is the narrowest, and the shearing speed is the highest. In general, the kneaded product is most affected by the shearing caused by kneading at the position where the shearing speed is the largest. Therefore, by making the maximum shearing speed larger than 800 s ⁻¹ , a state in which aggregation of the coarse pigment is unlikely to occur can be maintained.

The maximum shear rate can be adjusted according to, for example, the shape of the kneading device and the rotational speed of the rotating body (eg, the blade 12 , the column portion 23 , etc.). Specifically, for example, in the kneading device 10 shown in FIG. 1 , the blade 12 is obtained from the maximum radius r of the blade 12 (the longest distance among the shortest distances from the rotation axis L1 of the blade 12 to the surface of the blade 12 ). The product of the outer circumference of the rotation orbit (2×maximum radius r×π) and the rotational speed of the blade 12 is the maximum moving speed of the kneaded product. Therefore, the shape of the blade 12 and the rotation speed of the blade 12 are adjusted to adjust the kneaded material. The maximum moving speed and clearance can be set to the desired maximum shear speed. In addition, for example, in the kneading device 20 shown in FIG. 2 , the rolling wheel 22 is obtained from the sum of the shortest distance D from the rotation axis L2 passing through the center of the column portion 23 to the rolling wheel 22 and the wheel width W of the rolling wheel The product of the outer circumference of the revolving orbit (2×[shortest distance D+wheel width W]×π) and the rotational speed of the column portion 23 is the maximum moving speed of the kneaded product. Therefore, by adjusting the shape of the rolling wheel and the level of the connecting portion 24 The length in the direction, the rotational speed of the column portion 23, the strength of the tension applied to the rollers, and the like can be adjusted to a desired shearing speed by adjusting the maximum moving speed and gap of the kneaded product.

When the kneading device 10 shown in FIG. 1 is used, the minimum value of the width of the gap C1 can be set to, for example, 0.1 mm to 3.0 mm, 0.1 mm to 1.0 mm, or 0.1 mm to 0.4 mm. The rotational speed of the vanes 12 (when the rotational speeds of the pair of vanes 12 are different from each other, the rotational speed of the vane 12 on the side with the faster rotational speed) can be set to, for example, 30 rpm to 300 rpm, 100 rpm to 200 rpm, or 120rpm～160rpm. The rotational speed ratio of the rotational speeds of the pair of blades 12 may be, for example, 2:1 to 1:2 or 1.5:1 to 1:1.5. Blades can use Sigma blade, tear-kneader blade, Z blade, double angle blade and so on.

When using the kneading apparatus 20 shown in FIG. 2, the minimum value of the width|variety of the clearance gap C2 can be set to 1 mm - 30 mm, 1 mm - 20 mm, or 1 mm - 5 mm, for example. The wheel width X of the roller 22 can be set to, for example, 10 mm to 100 mm, 20 mm to 50 mm, or 30 mm to 40 mm. In addition, the rotational speed of the column portion 23 (revolution speed of the rollers) can be, for example, 10 rpm to 100 rpm, 10 rpm to 60 rpm, or 15 rpm to 45 rpm. The rotation speed of the roller can be set to, for example, 10 rpm to 100 rpm, 10 rpm to 60 rpm, or 15 rpm to 45 rpm. The rotation speed of the roller can be the same as the revolution speed of the roller.

The maximum moving speed of the kneaded material can be set to, for example, 500 mm/s to 3500 mm/s, 700 mm/s to 3000 mm/s, or 2000 mm/s to 3000 mm/s.

In the kneading step, the mixture may be kneaded at a temperature lower than 110°C. Crystallization of the crude pigment can be further suppressed by the kneading temperature being lower than 110°C. From this viewpoint, the kneading temperature may be 100°C or lower or 90°C or lower. The kneading temperature may be, for example, 25°C or higher, 40°C or higher, or 60°C or higher. The kneading temperature may be 110°C or higher. The kneading temperature may be, for example, 25°C to 150°C, 25°C or higher and less than 110°C, 40°C to 100°C, or 60°C to 90°C. In addition, the said kneading temperature is the temperature of the mixture (kneaded product) at the time of kneading. In the kneading step, in order to adjust the temperature of the kneaded product to the above-mentioned range, a temperature adjusting device can be used. For example, the mixture can be heated by flowing a heat medium (eg, ethylene glycol) heated by the temperature adjusting device in the jacket of the kneading device.

In the kneading step, the electricity consumed by the kneading of the mixture is more than 10.0 kWh per 1 kg of crude pigment. Here, "the amount of electricity consumed by the kneading of the mixture" has the same meaning as the energy input into the mixture by the kneading. The total power consumption was obtained by subtracting the power consumption of the kneading apparatus when the kneading apparatus was idling for the same time as the kneading time without adding the mixture to the kneading apparatus. However, in the case of consuming electric power for heating, the electric power for heating (for example, the electric power for heating the heat medium by the temperature adjustment device) is not included in the electric power.

From the viewpoint of further refining the crude pigment to obtain a color filter pigment with a more excellent brightness improvement effect, the power consumption for kneading the mixture can be 14.0 kWh or more or 25.0 kWh or more per 1 kg of the crude pigment. From the viewpoint of suppressing aggregation of the crude pigment due to excessive kneading, the amount of electricity consumed by kneading the mixture may be 100.0 kWh or less, 70.0 kWh or less, or 50.0 kWh or less per 1 kg of the crude pigment. From these viewpoints, the amount of electricity consumed for kneading the mixture can be more than 10.0 kWh and 100.0 kWh or less, 14.0 kWh to 70.0 kWh, or 14.0 kWh to 50.0 kWh per 1 kg of crude pigment. Furthermore, the amount of electricity consumed by the kneading of the mixture can be determined according to the kneading time, the shape of the kneading device, the rotational speed of the rotating body (for example, the blade 12, the column portion 23, etc.), the mixing ratio of the mixture, the type of the organic solvent in the mixture, and the like. Adjustment.

The kneading time may be 5 hours or more, 7 hours or more, or 9 hours or more from the viewpoint of obtaining a color filter pigment with a more excellent brightness improvement effect by further refining the coarse pigment. The kneading time may be 100 hours or less, 50 hours or less, or 30 hours or less from the viewpoint of suppressing aggregation of the crude pigment due to excessive kneading. From these viewpoints, the kneading time may be 5 hours to 100 hours, 7 hours to 50 hours, or 9 hours to 30 hours.

It is preferable to use the organic solvent which does not dissolve a crude pigment and the inorganic salt mentioned later. As an organic solvent, it is preferable to use an organic solvent which can suppress crystal growth. As such an organic solvent, a water-soluble organic solvent can be preferably used. As the organic solvent, for example, diethylene glycol, glycerol, ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, liquid polyethylene glycol, liquid polypropylene glycol, 2-(methoxyl Methoxy)ethanol, 2-butoxyethanol, 2-(isoamyloxy)ethanol, 2-(hexyloxy)ethanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol Alcohol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol Propylene glycol monoethyl ether, trimethyl phosphate, 4-butyrolactone, propylene carbonate, N-methyl-2-pyrrolidone, methanol, ethylene cyanohydrin, etc. One kind of organic solvent may be used alone, or a plurality of kinds may be used in combination.

From the viewpoint of promoting the wetting of the surface of the pigment particles and making the pigment particles more efficient, the amount of the organic solvent (for example, a water-soluble organic solvent) used may be 1 part by mass or more, relative to 100 parts by mass of the crude pigment 30 parts by mass or more or 50 parts by mass or more. From the viewpoint that the force applied to the crude pigment during kneading becomes larger due to the high viscosity of the mixture, and the aggregation of the crude pigment during kneading can be further suppressed, an organic solvent (such as a water-soluble pigment) is added to 100 parts by mass of The usage amount of organic solvent) may be 500 parts by mass or less, 400 parts by mass or less, or 200 parts by mass or less. From these viewpoints, the use amount of an organic solvent (eg, a water-soluble organic solvent) may be 1 part by mass to 500 parts by mass, 30 parts by mass to 400 parts by mass, or 50 parts by mass to 200 parts by mass relative to 100 parts by mass of the crude pigment. parts by mass. In addition, the usage-amount of an organic solvent can also be said to be the content of the organic solvent in a mixture.

As the inorganic salt, an inorganic salt having solubility in water and/or methanol can be preferably used, and an inorganic salt (water-soluble inorganic salt) having solubility in water can be preferably used. Specific examples of the inorganic salt include sodium chloride, potassium chloride, lithium chloride, sodium sulfate, and the like. The average particle diameter (average primary particle diameter) of the primary particles of the inorganic salt is, for example, 0.5 μm to 50 μm. Such inorganic salts can be easily obtained by pulverizing ordinary inorganic salts. The average primary particle diameter of the inorganic salt can be measured by the same method as the average primary particle diameter of the pigment described later. Specifically, the inorganic salt can be ultrasonically dispersed in cyclohexane, then photographed with a microscope, and the average particle size of the primary particles is calculated from the average value of 40 primary particles constituting the aggregate on the two-dimensional image ( average primary particle diameter).

From the viewpoint that the force applied to the crude pigment during kneading becomes larger and the aggregation of the crude pigment during kneading can be further suppressed, the amount of the inorganic salt (for example, water-soluble inorganic salt) to be used can be adjusted based on 1 part by mass of the crude pigment. It is 30 parts by mass or more, 40 parts by mass or more, or 50 parts by mass or more. From the viewpoint of improving the production efficiency of the pigment, the use amount of the inorganic salt (eg, water-soluble inorganic salt) may be 100 parts by mass or less, 80 parts by mass or less, or 60 parts by mass or less with respect to 1 part by mass of the crude pigment. From these viewpoints, the use amount of the inorganic salt (eg, water-soluble inorganic salt) may be 30 parts by mass to 100 parts by mass, 30 parts by mass to 60 parts by mass, or 40 parts by mass to 60 parts by mass relative to 1 part by mass of the crude pigment. parts by mass. In addition, the usage-amount of an inorganic salt can also be said to be the content of the inorganic salt in a mixture.

In the kneading step, it is preferable not to use water. The usage-amount of water may be, for example, 20 parts by mass or less, 10 parts by mass or less, or 5 parts by mass or less, relative to 100 parts by mass of the crude pigment.

After the kneading step, a washing step of washing the kneaded mixture may be performed. As the washing, washing with water, washing with hot water, washing with an organic solvent (for example, an organic solvent with a low surface tension such as methanol), and a combination of these can be employed depending on the type of inorganic salt. When a water-soluble inorganic salt and a water-soluble organic solvent are used, the organic solvent and the inorganic salt can be easily removed by washing with water.

In the case of using an acid-encapsulated crude pigment (for example, a crude pigment having a pH of less than 5), the washing step can be performed using an alkaline aqueous solution such as an aqueous potassium hydroxide solution. By using an alkaline aqueous solution, the counter anion is removed from a part of the halogenated metal phthalocyanine protonated under acidic conditions, heat resistance is improved, and the effect of further improving brightness tends to be obtained. From the viewpoint of easily obtaining the above-mentioned effects, as the alkaline aqueous solution, an aqueous solution having a pH of more than 8 at 25° C. can be used. The temperature of the alkaline aqueous solution may be, for example, 40°C to 90°C.

Washing can be performed by stirring the mixture in a washing solution (eg, water, organic solvent, or alkaline aqueous solution, etc.). The washing can be repeated, for example, in the range of 1 to 5 times. The amount of the cleaning liquid used for one cleaning may be, for example, 200 parts by mass to 1500 parts by mass with respect to 100 parts by mass of the total amount of the mixture. Acid cleaning can also be performed if desired.

After washing, operations such as filtering, drying, pulverizing, etc. may also be performed on the washed mixture (solids mainly composed of pigments) as required. Examples of drying after the washing and filtration include, for example, a batch or continuous process for dehydration and/or desolvation of pigments by heating at 80° C. to 120° C. with a heating source installed in a dryer. type drying, etc. As a dryer, a box-type dryer, a belt dryer, a spray dryer, etc. are mentioned normally. In particular, spray drying using a spray dryer is preferable because it is easy to disperse when making a paste. When using an organic solvent for washing|cleaning, it is preferable to vacuum-dry at 0 degreeC - 60 degreeC.

The pulverization after drying is not an operation to increase the specific surface area or reduce the average particle size of the primary particles, but to make the pigment a ramp as in the case of drying using, for example, a box dryer or a belt dryer. It is an operation performed by dispersing and powdering the pigment when it is in a state or the like. For example, pulverization by a mortar, a hammer mill, a disk mill, a pin mill, a jet mill, or the like is mentioned.

According to the above-mentioned production method, compared with the pigmentation of the halogenated metal phthalocyanine crude pigment by the conventional method, it can be further refined. That is, the pigment obtained by the above-described production method is a further refined halogenated metal phthalocyanine pigment, and when used as a color filter pigment, the pixel portion (especially the green pixel portion) can be further improved. brightness. In general, the smaller the particle diameter (primary particle diameter) of the color filter pigment, the more the brightness and contrast of the pixel portion can be improved. Therefore, the halogenated metal phthalocyanine pigment obtained by the above production method is used as In the case of a green pigment for color filters, there is a tendency that an excellent contrast ratio can be obtained.

The average particle diameter (average primary particle diameter) of the primary particles of the pigment obtained by the method is, for example, 30 nm or less. According to the method, for example, a pigment having an average primary particle diameter of 25 nm or less can be obtained. The average primary particle diameter of the pigment may be 10 nm or more. Here, the average primary particle diameter is an average value of the major diameters of the primary particles, and can be obtained by measuring the major diameters of the primary particles in the same manner as in the measurement of the average aspect ratio described later.

The average aspect ratio of the primary particles of the pigment is, for example, 1.2 or more, 1.3 or more, 1.4 or more, or 1.5 or more. The average aspect ratio of the primary particles of the pigment is, for example, less than 2.0, 1.8 or less, 1.6 or less, or 1.4 or less. According to the pigment having such an average aspect ratio, more excellent brightness and contrast can be obtained.

The pigment having an average aspect ratio of primary particles in the range of 1.0 to 3.0 preferably does not contain primary particles with an aspect ratio of 5 or more, more preferably does not contain primary particles with an aspect ratio of 4 or more, and more preferably does not contain an aspect ratio Primary particles with more than 3.

The aspect ratio and the average aspect ratio of the primary particles can be measured by the following methods. First, particles in the field of view are photographed with a transmission electron microscope (eg, JEM-2010 manufactured by JEOL Ltd.). Then, the long diameter (long diameter) and the short diameter (short diameter) of the primary particles existing on the two-dimensional image are measured, and the ratio of the long diameter to the short diameter is used as the aspect ratio of the primary particle. In addition, for 40 primary particles, the average value of the major axis and the minor axis was obtained, and the ratio of the major axis to the minor axis was calculated using these values, and this was taken as the average aspect ratio. At this time, the pigment as a sample is ultrasonically dispersed in a solvent (for example, cyclohexane), and then photographed with a microscope. In addition, a scanning electron microscope can also be used instead of a transmission electron microscope. [Example]

Hereinafter, the content of the present invention will be described in more detail using experimental examples, but the present invention is not limited to the following experimental examples.

<Synthesis of Coarse Pigments> (Synthesis of Coarse Pigment A1) Into a 300 ml flask were charged 91 g of sulfonic acid chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 109 g of aluminum chloride (manufactured by Kanto Chemical Co., Ltd.), and 15 g of sodium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) Manufactured by Kogyo Co., Ltd.), 30 g of zinc phthalocyanine (manufactured by DIC Co., Ltd.), 230 g of bromine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), then heated to 130°C, and heated to 130°C. 40 hours at 130°C. After the reaction mixture (reaction solution) was taken out into water and the precipitate was deposited, the precipitate was filtered, washed with water, and dried to obtain a crude pigment A1. In addition, the water washing was performed until the difference between the pH of the filtrate and the pH of the water used for washing became ±0.2.

About the crude pigment A1, mass analysis by JMS-S3000 by Nippon Electronics Co., Ltd. was performed, and it was confirmed that it was a halogenated zinc phthalocyanine having an average bromine number of 13.2 and an average chlorine number of 1.8. Furthermore, the delay time (Delay Time) during mass analysis was 500 ns, the laser intensity (Laser Intensity) was 44%, and the Resolving Power Value (Resolving Power Value) of the peak at m/z=1820 or more and 1860 or less was 31804 .

(Synthesis of Coarse Pigment A2) Into a 300 ml flask were charged 90 g of sulfonyl chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 105 g of aluminum chloride (manufactured by Kanto Chemical Co., Ltd.), and 14 g of sodium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) Manufactured by Kogyo Co., Ltd.), 27 g of zinc phthalocyanine (manufactured by DIC Co., Ltd.), 55 g of bromine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), then heated to 130°C, and heated to 130°C. 40 hours at 130°C. After the reaction mixture (reaction solution) was taken out into water and the precipitate was deposited, the precipitate was filtered, washed with water, and dried to obtain a crude pigment A2. In addition, washing with water was performed until the pH of the filtrate became pH equivalent to the water used for washing.

About crude pigment A2, mass analysis by JMS-S3000 by JEOL Ltd. was performed, and it was confirmed that it was a halogenated zinc phthalocyanine having an average bromine number of 9.3 and an average chlorine number of 2.9. In addition, the delay time (Delay Time) during mass analysis was 510 ns, the laser intensity (Laser Intensity) was 40%, and the resolving power value (Resolving Power Value) of the peak at m/z=1820 or more and 1860 or less was 65086 .

(Synthesis of Coarse Pigment A3) Into a 300 ml flask were charged 91 g of sulfonic acid chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 109 g of aluminum chloride (manufactured by Kanto Chemical Co., Ltd.), and 15 g of sodium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) Manufactured by Kogyo Co., Ltd.), 30 g of chloroaluminum phthalocyanine (manufactured by Tokyo Chemical Industry Co., Ltd.), 230 g of bromine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), then heated to 130°C, and heated to 130°C. 40 hours at °C. After the reaction mixture (reaction solution) was taken out into water and the precipitate was deposited, the precipitate was filtered, washed with water, and dried to obtain a crude pigment A3. In addition, the water washing was performed until the difference between the pH of the filtrate and the pH of the water used for washing became ±0.2.

Mass analysis using JMS-S3000 manufactured by Nippon Electronics Co., Ltd. was carried out for the crude pigment A3, and it was confirmed that the average number of bromines was 14.3 and the average number of chlorines was 1.4 (excluding chlorine atoms of axial ligands (chlorine groups). )) of chloroaluminum phthalocyanines (halogenated aluminum phthalocyanines with a chlorine group in the axial ligand). In addition, the delay time (Delay Time) during mass analysis was 275 ns, the laser intensity (Laser Intensity) was 40%, and the resolving power value (Resolving Power Value) of the peak at m/z=1820 or more and 1860 or less was 56320 .

(Synthesis of Coarse Pigment A4) Into a 300 ml flask were charged 91 g of sulfonic acid chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 109 g of aluminum chloride (manufactured by Kanto Chemical Co., Ltd.), and 15 g of sodium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) Manufactured by Kogyo Co., Ltd.), 30 g of copper phthalocyanine (manufactured by Tokyo Chemical Industry Co., Ltd.), 230 g of bromine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) for 40 hours. After the reaction mixture (reaction solution) was taken out into water and the precipitate was deposited, the precipitate was filtered, washed with water, and dried to obtain a crude pigment A4. In addition, the water washing was performed until the difference between the pH of the filtrate and the pH of the water used for washing became ±0.2.

About crude pigment A4, mass analysis by JMS-S3000 by JEOL Ltd. was performed, and it was confirmed that it was a halogenated copper phthalocyanine having an average bromine number of 13.0 and an average chlorine number of 2.6. Furthermore, the delay time (Delay Time) during mass analysis was 275 ns, the laser intensity (Laser Intensity) was 34%, and the Resolving Power Value (Resolving Power Value) of the peak at m/z=1820 or more and 1860 or less was 42805 .

<pH measurement of crude pigment> 5 g of crude pigments (coarse pigments A1 to A4) and 5 g of methanol were weighed and mixed in a 300 ml beaker, and then 100 ml of ion-exchanged water was further weighed, and the mixture was set with a hot stirrer for 5 minutes. Boil and continue to boil for 5 minutes. Next, it was left to cool to 30° C. or less, transferred to a 100-ml measuring cylinder, adjusted to 100 ml in total with ion-exchanged water, filtered, and the pH of the filtrate was measured. The pH was measured using a PH71 Pasonal (personal) pH meter manufactured by Yokogawa Electric Corporation. The results are shown in Table 1.

<Experimental example 1> (Pigmentation of crude pigment) 320 g of crude pigment A1 and 3200 g of pulverized sodium chloride (manufactured by Naruto Salt Industry Co., Ltd., trade name: fine-grained fine-grained salt) were pulverized. The average primary particle diameter: 120 μm) and 504 g of diethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.) were charged into a double-arm kneader (manufactured by Inoue Seisakusho Co., Ltd., product name: KHD-8, airtight Type tangent type), these mixtures were kneaded while being adjusted so that the kneading temperature (the temperature of the mixture during kneading) became 80°C (temperature fluctuation range: about 2°C to 3°C). At this time, as the vane of the double-arm kneader, a sigma vane having a shape with an outer circumference of the rotating orbit of 0.35 m and the minimum width of the gap between the vane and the inner wall surface of the kneading chamber (trough) was 0.5 mm was used. The maximum moving speed of the kneaded product (the outer circumference of the rotation orbit of the blade × the rotation speed of the blade) was set by setting the rotation speed of the blade (the rotation speed of the faster side) to 140 rpm (rotation speed ratio = 1:1.4). ) was set to 817 mm/s, and the maximum shear rate (the minimum value of the maximum moving speed of the kneaded product×the width of the gap) was set to 1633 s ^-1 . In addition, the power consumption of the double-arm kneader was measured with a Watt Monitor TAP-TST8N manufactured by SANWA SUPPLY, and the kneading time was adjusted so that the power consumption per 1 kg of crude pigment A1 is 15.0 kWh. The mixing time was set to 10 hours. The kneaded mixture was taken out into 16 kg of water at 80°C, stirred for 1 hour, filtered, washed with hot water, dried, and pulverized to obtain green pigment G1.

(Measurement of average primary particle size) The green pigment G1 was ultrasonically dispersed in cyclohexane, then photographed with a microscope, and the average particle diameter of the primary particles (average primary particle diameter) was calculated from the average value of 40 primary particles constituting the aggregate on the two-dimensional image. ). The average particle diameter of the primary particles was 28 nm.

(Evaluation of contrast and brightness) Using zirconium beads of 0.3 mm to 0.4 mm, 1.65 g of pigment yellow 138 (Chromofine Yellow 6206EC manufactured by Dainisei Chemical Co., Ltd.) was mixed with a paint shaker manufactured by Toyo Seiki Co., Ltd. ) was dispersed with 3.85 g of DISPERBYK-161 (manufactured by BYK Chemicals) and 11.00 g of propylene glycol monomethyl ether acetate for 2 hours to obtain a dispersion.

4.0 g of the dispersion, 0.98 g of Unidic ZL-295, and 0.22 g of propylene glycol monomethyl ether acetate were added and mixed with a paint shaker to obtain a yellow composition for coloring ( TY1).

Using zirconium beads of 0.3 mm to 0.4 mm, 2.48 g of the green pigment G1 obtained in Experimental Example 1 and 1.24 g of BYK-LPN6919 and 1.86 BYK-LPN6919 and 1.86 manufactured by BYK Chemicals were mixed using a paint shaker manufactured by Toyo Seiki Co., Ltd. g Unidic ZL-295 manufactured by DIC Co., Ltd. and 10.92 g of propylene glycol monomethyl ether acetate were dispersed together for 2 hours to obtain a color filter pigment dispersion (MG1).

4.0 g of the color filter pigment dispersion (MG1), 0.98 g of Unidic ZL-295 manufactured by DIC Co., Ltd., and 0.22 g of propylene glycol monomethyl ether acetic acid were added The ester was mixed with a paint shaker to obtain a composition for evaluation (CG1) for forming a green pixel portion for a color filter.

The composition for evaluation (CG1) was spin-coated on a soda glass substrate, dried at 90° C. for 3 minutes, and then heated at 230° C. for 1 hour. Thereby, the glass substrate for contrast evaluation which has a colored film on a soda glass substrate was produced. In addition, the thickness of the coloring film obtained by heating at 230 degreeC for 1 hour was adjusted to 1.8 micrometers by adjusting the rotation speed at the time of spin coating.

Further, the coating liquid obtained by mixing the prepared yellow composition for toning (TY1) and the composition for evaluation (CG1) was spin-coated on a soda glass substrate, dried at 90° C. for 3 minutes, and then applied to a soda glass substrate. Heated at 230°C for 1 hour. Thereby, the glass substrate for brightness evaluation which has a colored film on a soda glass substrate was produced. Furthermore, by adjusting the mixing ratio of the yellow composition for toning (TY1) and the composition for evaluation (CG1), and the rotation speed during spin coating, a colored film obtained by heating at 230° C. for 1 hour was prepared in The chromaticity (x, y) under the C light source becomes (0.275, 0.570) tinted film.

The contrast ratio of the coloring film on the glass substrate for contrast evaluation was measured using a contrast tester CT-1 manufactured by Tsusaka Electric Co., Ltd., and the brightness evaluation was measured using U-3900 manufactured by Hitachi High-Tech Science Co., Ltd. Brightness with a tinted film on a glass substrate. The results are shown in Table 1. In addition, the contrast ratio and brightness|luminance shown in Table 1 are the values based on the contrast ratio and brightness|luminance of Experimental Example 7.

<Experimental example 2> The blade was changed to a sigma blade having a larger diameter, and kneading was performed so that the minimum value of the width of the gap between the blade and the inner wall surface of the kneading chamber was 0.25 mm, and the shear rate was set to 3267 s. Except for ^-1 , green pigment G2 was obtained in the same manner as in Experimental Example 1. In addition, the electric power consumed for kneading the mixture was 28.3 kWh per 1 kg of crude pigment A1. In addition, in the same manner as in Experimental Example 1, the average primary particle diameter of the green pigment G2 was measured. Moreover, except having used the green pigment G2 instead of the green pigment G1, it carried out similarly to Experimental Example 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured the contrast and brightness. The results are shown in Table 1.

<Experimental example 3> A green pigment G3 was obtained in the same manner as in Experimental Example 1, except that the kneading temperature was set to 130°C. In addition, the electric power consumed for kneading the mixture was 13.7 kWh per 1 kg of crude pigment A1. In addition, in the same manner as in Experimental Example 1, the average primary particle diameter of the green pigment G3 was measured. Moreover, except having used green pigment G3 instead of green pigment G1, it carried out similarly to Experimental Example 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured the contrast and brightness. The results are shown in Table 1.

<Experimental Example 4> A green pigment G4 was obtained in the same manner as in Experimental Example 1, except that the usage amount of the crude pigment A1 was 80 g and the usage amount of the sodium chloride was 40 times the usage amount of the crude pigment. In addition, the electric power consumed for kneading the mixture was 14.6 kWh per 1 kg of crude pigment A1. In addition, the average primary particle size of the green pigment G4 was measured in the same manner as in Experimental Example 1. Moreover, except having used green pigment G4 instead of green pigment G1, it carried out similarly to Experiment 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured contrast and brightness. The results are shown in Table 1.

<Experimental example 5> A green pigment G5 was obtained in the same manner as in Experimental Example 4, except that the kneaded mixture was taken out to a 5% potassium hydroxide aqueous solution (pH at 25°C: 13.8) at 80°C instead of water at 80°C. In addition, in the same manner as in Experimental Example 1, the average primary particle size of the green pigment G5 was measured. Moreover, except having used green pigment G5 instead of green pigment G1, it carried out similarly to Experiment 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured contrast and brightness. The results are shown in Table 1.

<Experimental example 6> 3 kg of crude pigment A1, 30 kg of pulverized sodium chloride, and 4.7 kg of diethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.) were charged into a mixing mill (Shinto Kogyo Co., Ltd.). Co., Ltd., product name: MSG-60E), these mixtures were kneaded at a kneading temperature of 80°C (the temperature of the mixture during kneading). At this time, as the roller in the mixing mill, a roller with a diameter of 1200 mm and a thickness of 360 mm was used, and the position of the roller and the strength of the tension applied to the roller were adjusted (the tension applied to the roller was set to 3365 kg) , so that the outer circumference of the revolving track of the rollers is 3.75 m and the minimum value of the width of the gap between the rollers and the bottom surface of the kneading chamber is 3 mm. In addition, the maximum moving speed of the kneaded product (the outer circumference of the revolving orbit of the roller × the rotational speed of the column portion) was set to 2500 mm/s by setting the rotational speed of the column portion (revolutional speed of the roller) to 40 rpm. , and the maximum shear rate (the minimum value of the maximum moving speed of the kneaded product×the width of the gap) was set to 833 s ⁻¹ . Furthermore, the rotation speed of the roller was set to 40 rpm. In addition, the power consumption of the kneader was measured using a Watt Monitor TAP-TST8N manufactured by Sanwa Supply, Inc., and the kneading time was adjusted so that the power consumption per 1 kg of crude Pigment A1 is 11.5 kWh. The mixing time was set at 2.5 hours. The kneaded mixture was taken out into 150 kg of water at 80°C, stirred for 1 hour, filtered, washed with hot water, dried, and pulverized to obtain green pigment G6.

The average primary particle size of the green pigment G6 was measured in the same manner as in Experimental Example 1. A glass substrate for contrast evaluation and a glass substrate for brightness evaluation were produced in the same manner as in Experimental Example 1 except that the green pigment G6 was used instead of the green pigment G1, and the contrast and the brightness were measured. The results are shown in Table 1.

<Experimental example 7> Kneading was performed by changing the blade to a sigma blade having a smaller diameter so that the minimum value of the width of the gap between the blade and the inner wall surface of the kneading chamber was 1 mm. At 70 rpm, the maximum movement speed of the kneaded product (the outer circumference of the rotation orbit of the blade × the rotation speed of the blade) was set to 408 mm/s, and the maximum shear speed (the maximum movement speed of the kneaded product × the minimum value of the width of the gap) was set to 408 mm/s. A green pigment was obtained in the same manner as in Experimental Example 1, except that the kneading time was 408 s ⁻¹ , the kneading time was 8 hours, and the power consumption for kneading the mixture was 8.0 kWh per 1 kg of the crude pigment A1 G7. In addition, in the same manner as in Experimental Example 1, the average primary particle size of the green pigment G7 was measured. Moreover, except having used green pigment G7 instead of green pigment G1, it carried out similarly to Experimental Example 1, produced the glass substrate for contrast evaluation, and the glass substrate for brightness evaluation, and measured contrast and brightness. The results are shown in Table 1.

<Experimental Example 8> A green pigment G8 was obtained in the same manner as in Experimental Example 7, except that the kneading time was 24 hours and the power consumption for kneading the mixture was 23.9 kWh per 1 kg of the crude pigment A1. In addition, in the same manner as in Experimental Example 1, the average primary particle size of the green pigment G8 was measured. Moreover, except having used the green pigment G8 instead of the green pigment G1, it carried out similarly to Experimental Example 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured the contrast and the brightness. The results are shown in Table 1.

[Table 1] coarse pigment pH of crude pigment Mixing device Mixing conditions alkaline aq cleaning Primary particle diameter Characteristic values (contrast, brightness) Maximum moving speed [mm/s] Narrowest gap [mm] Rotation speed [rpm] Mixing time [hr] Electricity [kWh/kg] Shear speed[/s] Mixing temperature Inorganic salt content [for coarse pigments] Monochrome evaluation: film thickness=1.8 μm Y138 Toning Evaluation: (0.275, 0.570) Contrast brightness Std. than Std. than Experimental example 1 A1 3.6 Kneader 817 0.5 140 10 15.0 1633 80℃ 10 times none 28nm 117% 103.7% Experimental example 2 Kneader 817 0.25 140 10 28.3 3267 80℃ 10 times none 26nm 123% 104.1% Experimental example 3 Kneader 817 0.5 140 10 13.7 1633 130℃ 10 times none 30nm 109% 102.7% Experimental example 4 Kneader 817 0.5 140 10 14.6 1633 80℃ 40 times none 25nm 128% 104.8% Experimental example 5 Kneader 817 0.5 140 10 14.6 1633 80℃ 40 times Have 25nm 130% 105.1% Experimental example 6 Mixer 2500 3 40 2.5 11.5 833 80℃ 10 times none 29nm 111% 102.9% Experimental example 7 Kneader 408 1 70 8 8.0 408 80℃ 10 times none 34nm Std. Std. Experimental example 8 Kneader 408 1 70 twenty four 23.9 408 80℃ 10 times none 35nm 98% 99.6%

<Experimental Example 9> A green pigment G9 was obtained in the same manner as in Experimental Example 5, except that the crude pigment A2 was used in place of the crude pigment A1. In addition, the electric power consumed for kneading the mixture was 14.7 kWh per 1 kg of crude pigment A2. In addition, in the same manner as in Experimental Example 1, the average primary particle size of the green pigment G9 was measured. In addition, Pigment Yellow 185 (Paliotol Yellow D1155 manufactured by BASF) was used in place of Pigment Yellow 138 (Cromofine Yellow 6206EC manufactured by Dainisei Chemicals), and the A glass substrate for contrast evaluation and a glass substrate for brightness evaluation were prepared in the same manner as in Experimental Example 1, except that the green pigment G9 was used instead of the green pigment G1 and the chromaticity (x, y) of the colored film was adjusted to (0.230, 0.670). , and measure the contrast and brightness. The results are shown in Table 2. In addition, the contrast ratio and brightness|luminance shown in Table 2 are the values based on the contrast ratio and brightness|luminance of Experimental Example 10.

<Experimental Example 10> A green pigment G10 was obtained in the same manner as in Experimental Example 7 except that the crude pigment A2 was used instead of the crude pigment A1. In addition, the electric power consumed for kneading the mixture was 8.0 kWh per 1 kg of crude pigment A2. In addition, in the same manner as in Experimental Example 1, the average primary particle size of the green pigment G10 was measured. Moreover, except having used the green pigment G10 instead of the green pigment G9, it carried out similarly to Experiment 9, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured the contrast and brightness. The results are shown in Table 2.

[Table 2] coarse pigment pH of crude pigment Mixing device Mixing conditions alkaline aq cleaning Primary particle diameter Characteristic values (contrast, brightness) Maximum moving speed [mm/s] Narrowest gap [mm] Rotation speed [rpm] Mixing time [hr] Electricity [kWh/kg] Shear speed[/s] Mixing temperature Inorganic salt content [for coarse pigments] Monochrome evaluation: film thickness=1.8 μm Y185 toning evaluation: (0.230, 0.670) Contrast brightness Std. than Std. than Experimental example 9 A2 3.3 Kneader 817 0.5 140 10 14.7 1633 80℃ 40 times Have 26nm 124% 103.7% Experimental Example 10 Kneader 408 1 70 8 8.0 408 80℃ 10 times none 31 nm Std. Std.

<Experimental Example 11> A green pigment G11 was obtained in the same manner as in Experimental Example 5 except that the crude pigment A3 was used instead of the crude pigment A1. In addition, the electric power consumed for kneading the mixture was 14.4 kWh per 1 kg of crude pigment A3. The average primary particle size of the green pigment G11 was measured in the same manner as in Experimental Example 1. Moreover, except having used the green pigment G11 instead of the green pigment G1, it carried out similarly to Experiment 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured the contrast and brightness. The results are shown in Table 3. In addition, the contrast ratio and brightness shown in Table 3 are values based on the contrast ratio and brightness of Experimental Example 12.

<Experimental Example 12> A green pigment G12 was obtained in the same manner as in Experimental Example 7 except that the crude pigment A3 was used in place of the crude pigment A1. In addition, the electric power consumed for kneading the mixture was 8.0 kWh per 1 kg of crude pigment A3. In addition, in the same manner as in Experimental Example 1, the average primary particle size of the green pigment G12 was measured. Moreover, except having used green pigment G12 instead of green pigment G1, it carried out similarly to Experimental Example 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured contrast and brightness. The results are shown in Table 3.

[table 3] coarse pigment pH of crude pigment Mixing device Mixing conditions alkaline aq cleaning Primary particle diameter Characteristic values (contrast, brightness) Maximum moving speed [mm/s] Narrowest gap [mm] Rotation speed [rpm] Mixing time [hr] Electricity [kWh/kg] Shear speed[/s] Mixing temperature Inorganic salt content [for coarse pigments] Monochrome evaluation: film thickness=1.8 μm Y138 Toning Evaluation: (0.275, 0.570) Contrast brightness Std. than Std. than Experimental Example 11 A3 4.6 Kneader 817 0.5 140 10 14.4 1633 80℃ 40 times Have 27nm 121% 103.8% Experimental example 12 Kneader 408 1 70 8 8.0 408 80℃ 10 times none 34nm Std. Std.

<Experimental Example 13> A green pigment G13 was obtained in the same manner as in Experimental Example 5 except that the crude pigment A4 was used instead of the crude pigment A1. In addition, the electric power consumed for kneading the mixture was 14.3 kWh per 1 kg of crude pigment A4. The average primary particle size of the green pigment G13 was measured in the same manner as in Experimental Example 1. Moreover, except having used green pigment G13 instead of green pigment G1, it carried out similarly to Experimental Example 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured the contrast and brightness. The results are shown in Table 4. In addition, the contrast and brightness shown in Table 4 are values based on the contrast and brightness of Experimental Example 14.

<Experimental Example 14> A green pigment G14 was obtained in the same manner as in Experimental Example 7 except that the crude pigment A4 was used instead of the crude pigment A1. In addition, the electric power consumed for kneading the mixture was 8.0 kWh per 1 kg of crude pigment A4. In addition, the average primary particle size of the green pigment G14 was measured in the same manner as in Experimental Example 1. Moreover, except having used green pigment G14 instead of green pigment G1, it carried out similarly to Experiment 1, produced the glass substrate for contrast evaluation and the glass substrate for brightness evaluation, and measured contrast and brightness. The results are shown in Table 4.

[Table 4] coarse pigment pH of crude pigment Mixing device Mixing conditions alkaline aq cleaning Primary particle diameter Characteristic values (contrast, brightness) Maximum moving speed [mm/s] Narrowest gap [mm] Rotation speed [rpm] Mixing time [hr] Electricity [kWh/kg] Shear speed[/s] Mixing temperature Inorganic salt content [for coarse pigments] Monochrome evaluation: film thickness=1.8 μm Y138 Toning Evaluation: (0.275, 0.570) Contrast brightness Std. than Std. than Experimental Example 13 A4 6.2 Kneader 817 0.5 140 10 14.3 1633 80℃ 40 times Have 36nm 101% 100.2% Experimental Example 14 Kneader 408 1 70 8 8.0 408 80℃ 10 times none 35nm Std. Std.

10, 20: Mixing device 11, 21: Mixing room 11a: inner wall surface 12: Blades 21a: Underside 22: Roller wheel 23: Pillar 24: Links 25: Compression spring C1, C2: Clearance D: shortest distance L1, L2: Rotation axis r: maximum radius W: Wheel width

FIG. 1 is a schematic cross-sectional view showing the internal structure of a kneading apparatus used in a production method according to an embodiment. 2 is a schematic plan view showing the internal structure of a kneading apparatus used in a production method of another embodiment. FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2 .

Claims (6)

A method for producing a pigment for color filters, comprising a kneading step of kneading a mixture comprising a coarse pigment, an inorganic salt and an organic solvent at a maximum shear speed exceeding 800 s ⁻¹ , the coarse pigment comprising zinc, iron, In the halogenated metal phthalocyanine with aluminum, magnesium, silicon or vanadium as the central metal, the electricity consumed by the mixing of the mixture in the mixing step is more than 10.0 kWh per 1 kg of the crude pigment. The method for producing a color filter pigment according to claim 1, wherein the pH of the crude pigment is less than 5, The central metal of the crude pigment is zinc, iron or magnesium. The method for producing a color filter pigment according to claim 1 or 2, wherein the pH of the crude pigment is less than 5, The manufacturing method further includes a washing step of washing the kneaded mixture obtained in the kneading step with an aqueous solution having a pH greater than 8 at 25°C. The method for producing a color filter pigment according to claim 1 or 2, wherein the average number of halogen atoms in one molecule of the halogenated metal phthalocyanine in the crude pigment is 9 or more. The method for producing a color filter pigment according to claim 1 or 2, wherein in the kneading step, the mixture is kneaded at a temperature lower than 110°C. The method for producing a color filter pigment according to claim 1 or 2, wherein the amount of the inorganic salt used in the kneading step is 30 parts by mass or more relative to 1 part by mass of the crude pigment.

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