Halogenated zinc phthalocyanine pigment and its production method

Abstract

A method for producing a zinc phthalocyanine halide pigment comprises: extracting zinc phthalocyanine halide in an alkaline aqueous solution and precipitating the extracted zinc phthalocyanine halide to obtain a crude zinc phthalocyanine halide pigment, wherein the zinc phthalocyanine halide is synthesized using a compound that reacts with water to generate an acid; and pigmenting the crude zinc phthalocyanine halide pigment.

Description

Technical Field

[0001] The present invention relates to a zinc halide phthalocyanine pigment and a method for producing the same. Background Art

[0002] Coloring compositions are currently used in a variety of fields. Specific applications of coloring compositions include printing inks, coatings, resin colorants, fiber colorants, and colorants for IT information recording (color filters, toners, inkjet printing). Coloring materials used in coloring compositions are mainly divided into pigments and dyes, with organic pigments, which excel in coloring power, attracting significant attention.

[0003] After synthesis, the organic compounds that make up organic pigments aggregate into aggregates called crude products. Therefore, the synthesized organic compounds cannot usually be used directly as pigments, and a pigmentation step is required to adjust the particle size. The aggregates (crude products) of the organic compounds that have been pigmented in the pigmentation step are called crude pigments. Fine organic pigments can be obtained by grinding the crude pigments through kneading or other methods.

[0004] As an organic pigment, zinc phthalocyanine halide pigments used in green pixel portions of color filters and the like have attracted attention (for example, see Patent Document 1).

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: International Publication No. 2018 / 043548 Pamphlet Summary of the Invention

[0008] Problems to be solved by the invention

[0009] An object of the present invention is to provide a novel method for producing a zinc phthalocyanine halide pigment that can further refine the pigment particles.

[0010] Methods for solving problems

[0011] As a method for synthesizing zinc phthalocyanine halides, for example, the chlorosulfonic acid method and the melting method are known. In these methods, a compound that reacts with water to produce an acid is used to synthesize zinc phthalocyanine halides. By precipitating the synthesized zinc phthalocyanine halides in water or an acidic solution, a crude pigment as an aggregate of zinc phthalocyanine halides can be obtained. In such a method, the acid from the compound that reacts with water to produce an acid usually adheres to the crude pigment. Therefore, before the crude pigment is pigmented, a washing process is performed to remove the acid attached to the crude pigment. However, the research results of the present inventors have shown that even if the crude pigment is washed until the pH of the filtrate reaches the same pH as the water used in the washing, acid will remain inside the crude pigment. The present invention is based on such research results.

[0012] Specifically, one aspect of the present invention relates to a method for producing a zinc phthalocyanine halide pigment, comprising: extracting zinc phthalocyanine halide in an alkaline aqueous solution and precipitating the extracted zinc phthalocyanine halide to obtain a crude zinc phthalocyanine halide pigment, wherein the zinc phthalocyanine halide is synthesized using a compound that generates an acid by reacting with water; and pigmenting the crude zinc phthalocyanine halide pigment.

[0013] According to the production method of the above aspect, internal inclusion of acid in the zinc phthalocyanine halide crude pigment can be suppressed, thereby obtaining a fine zinc phthalocyanine halide pigment. In addition, the production method of the above aspect can obtain a zinc phthalocyanine halide pigment with a large amount of base adsorption.

[0014] In one embodiment, the concentration of the basic compound contained in the alkaline aqueous solution may be 1% by mass or more.

[0015] In one embodiment, the alkaline aqueous solution may contain a hydroxide of an alkali metal or an alkaline earth metal.

[0016] In one embodiment, the temperature of the alkaline aqueous solution may be 5 to 90°C.

[0017] In one embodiment, the pH of the crude zinc phthalocyanine halide pigment may be 5.0 or higher.

[0018] In one embodiment, the amount of Al contained in the crude zinc phthalocyanine halide pigment may be 3000 mass ppm or less.

[0019] Another aspect of the present invention relates to a zinc phthalocyanine halide pigment having an alkali adsorption amount of 0.13 mol / kg or more and an Al content of 3000 mass ppm or less.

[0020] According to the zinc phthalocyanine halide pigment of the above aspect, the amount of the dispersant used together with the pigment can be reduced, and the inconvenience caused by adding a large amount of the dispersant can be reduced.

[0021] Effects of the Invention

[0022] The present invention provides a novel method for producing a zinc phthalocyanine halide pigment capable of further miniaturizing pigment particles. Furthermore, the present invention provides a novel zinc phthalocyanine halide pigment having a high alkali adsorption capacity and a low Al content. DETAILED DESCRIPTION

[0023] Preferred embodiments of the present invention will be described below, but the present invention is not limited to the following embodiments.

[0024] A method for producing a zinc phthalocyanine halide pigment according to one embodiment includes: a first step of extracting and precipitating zinc phthalocyanine halide in an alkaline aqueous solution to obtain a crude zinc phthalocyanine halide pigment, wherein the zinc phthalocyanine halide is synthesized using a compound that generates an acid when reacted with water; and a second step of pigmenting the crude zinc phthalocyanine halide pigment. The zinc phthalocyanine halide is a compound having a structure represented by the following formula (1).

[0025] [Chemistry 1]

[0026]

[0027] [In formula (1), X 1 ~X 16 Each independently represents a hydrogen atom or a halogen atom.]

[0028] Examples of the halogen atom include fluorine, chlorine, bromine, and iodine. The zinc phthalocyanine halide preferably has at least one of a bromine atom and a chlorine atom as a halogen atom, and preferably has a bromine atom. The zinc phthalocyanine halide may also have only one or both of a chlorine atom and a bromine atom as a halogen atom. That is, X in the above formula (1) 1 ~X 16 It may be a chlorine atom or a bromine atom.

[0029] For example, the first step includes a synthesis step of synthesizing zinc phthalocyanine halide using a compound that generates an acid by reacting with water, and a precipitation step of extracting and precipitating the synthesized zinc phthalocyanine halide in an alkaline aqueous solution.

[0030] Examples of a method for synthesizing zinc phthalocyanine halide using a compound that generates an acid by reacting with water include a chlorosulfonic acid method and a melting method.

[0031] The chlorosulfonic acid method involves dissolving zinc phthalocyanine in a sulfur oxide solvent such as chlorosulfonic acid and then adding chlorine gas or bromine to the solution for halogenation. The reaction is carried out at a temperature of 20 to 120°C for 3 to 20 hours. In the chlorosulfonic acid method, the sulfur oxide solvent, such as chlorosulfonic acid, is a compound that reacts with water to produce an acid. For example, chlorosulfonic acid reacts with water to produce hydrochloric acid and sulfuric acid.

[0032] Examples of the melt method include halogenating zinc phthalocyanine with a halogenating agent in a melt at approximately 10 to 170°C comprising one or a mixture of two or more compounds serving as solvents during halogenation, such as aluminum chloride and aluminum bromide, titanium halides such as titanium tetrachloride, alkali metal halides or alkaline earth metal halides (hereinafter referred to as "alkaline (earth) metal halides") such as sodium chloride and sodium bromide, and various compounds serving as solvents during halogenation, such as thionyl chloride. In the melt method, the compounds serving as solvents during halogenation, such as aluminum halides, titanium halides, alkaline (earth) metal halides, and thionyl chloride, are compounds that react with water to generate an acid. For example, aluminum chloride reacts with water to generate hydrochloric acid.

[0033] A preferred aluminum halide is aluminum chloride. In the above method using an aluminum halide, the amount of the aluminum halide added is usually 3 times or more, preferably 10 to 20 times the molar amount, of zinc phthalocyanine.

[0034] Aluminum halide can be used alone, but using an alkaline (earth) metal halide in combination with an aluminum halide can further lower the melting temperature, which is advantageous in terms of operation. A preferred alkaline (earth) metal halide is sodium chloride. The amount of alkaline (earth) metal halide to be added is preferably 1 to 15 parts by mass per 10 parts by mass of aluminum halide, within a range that produces a molten salt.

[0035] Examples of the halogenating agent include chlorine, sulfuryl chloride, and bromine.

[0036] The halogenation temperature is preferably 10 to 170° C., more preferably 30 to 140° C. Furthermore, pressure may be applied to accelerate the reaction rate. The reaction time may be 5 to 100 hours, preferably 30 to 45 hours.

[0037] The fusion method is preferred because it allows for the arbitrarily controlled ratio of the specific halogen atoms in the generated zinc phthalocyanine halide by adjusting the ratio of chloride, bromide, and iodide in the molten salt or by varying the amount of chlorine, bromine, iodine, etc. introduced and the reaction time. Furthermore, the fusion method minimizes decomposition of the raw materials during the reaction, resulting in a higher yield based on the raw materials. Furthermore, the reaction can be carried out using inexpensive equipment without the use of a strong acid.

[0038] In this embodiment, by optimizing the raw material feeding method, the type and amount of catalyst used, the reaction temperature, and the reaction time, a zinc phthalocyanine halide having a halogen atom composition different from that of the existing zinc phthalocyanine halide can be obtained.

[0039] In the precipitation step, for example, the mixture containing the zinc phthalocyanine halide and the compound that reacts with water to generate an acid obtained after the reaction is added to an alkaline aqueous solution as an extract to precipitate (precipitate) the zinc phthalocyanine halide.

[0040] In the method in the past, what is used in the precipitation operation is acidic aqueous solution such as water or hydrochloric acid rather than alkaline aqueous solution, therefore the acid of the compound that produces acid from the above-mentioned reaction with water can enter in the precipitate, but, even if for example precipitate is washed until the pH of filtrate becomes the pH equal to the water used in washing, the acid of inner package (from the acid of the compound that produces acid from the reaction with water etc.) is also difficult to be removed in the precipitate, and acid can remain in the thick pigment. As its reason, think because, in zinc halide phthalocyanine, as the distance of the zinc of central metal and the nitrogen atom on isoindoline unit is far, at central metal (zinc) periphery, there is large hole, therefore after the nitrogen of phthalocyanine ring is protonated under acidic condition, counter anion (for example chloride ion) is easily close to central metal (zinc), and counter anion and central metal (zinc) are easily combined and form stable structure. On the other hand, in the present embodiment, in the above-mentioned precipitation operation, use alkaline aqueous solution, therefore the generation of acid is suppressed or the acid that produces is neutralized.Therefore can suppress acid to be enclosed in the thick pigment of zinc halide phthalocyanine.

[0041] The mixture containing zinc phthalocyanine halide and the compound that generates an acid by reacting with water contains, for example, 20 to 60% by mass of zinc phthalocyanine halide and 40 to 80% by mass of the compound that generates an acid by reacting with water.

[0042] An alkaline aqueous solution is an aqueous solution having alkalinity, and is obtained, for example, by dissolving an alkaline compound in water. Therefore, an alkaline aqueous solution can also be said to be an aqueous solution containing an alkaline compound.

[0043] As the alkaline compound, any compound that shows alkalinity in aqueous solution may be used, and examples thereof include hydroxides of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide, and calcium hydroxide, carbonates of alkali metals or alkaline earth metals such as sodium carbonate and potassium carbonate, bicarbonates of alkali metals or alkaline earth metals such as sodium bicarbonate, potassium bicarbonate, and calcium bicarbonate, acetates of alkali metals or alkaline earth metals such as sodium acetate, potassium acetate, and calcium acetate, and ammonia. Among them, for example, in the melting method, from the perspective of easily removing aluminum-containing components such as aluminum hydroxide that can serve as inorganic flocculants, further suppressing pigment aggregation, and further suppressing acid generation, compounds with a pKb of 5 or less are preferred, and compounds with a pKb of 1 or less are more preferred. Specifically, it is preferred to use at least one selected from the group consisting of hydroxides of alkali metals or alkaline earth metals and acetates of alkali metals or alkaline earth metals, more preferably hydroxides of alkali metals or alkaline earth metals, and even more preferably sodium hydroxide. The alkaline compound can be used alone or in combination of two or more.

[0044] From the perspective of further suppressing acid production, the concentration of the alkaline compound contained in the alkaline aqueous solution is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, based on the total mass of the alkaline aqueous solution. From the perspective of preventing particle coarsening, the concentration of the alkaline compound contained in the alkaline aqueous solution is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on the total mass of the alkaline aqueous solution.

[0045] From the perspective of more fully suppressing acid production, the amount of the alkaline compound contained in the alkaline aqueous solution is preferably 100 parts by mass or more, more preferably 200 parts by mass or more, and even more preferably 300 parts by mass or more, relative to 100 parts by mass of the compound that reacts with water to generate an acid contained in the mixture added to the alkaline aqueous solution. From the perspective of preventing particle coarsening, the amount of the alkaline compound contained in the alkaline aqueous solution is preferably 600 parts by mass or less, more preferably 500 parts by mass or less, and even more preferably 400 parts by mass or less, relative to 100 parts by mass of the compound that reacts with water to generate an acid contained in the mixture added to the alkaline aqueous solution.

[0046] From the viewpoint of further suppressing acid generation, the pH of the alkaline aqueous solution at 25°C is preferably 8 or higher, more preferably 10 or higher, and even more preferably 13 or higher. The pH of the alkaline aqueous solution at 25°C may be 14 or lower.

[0047] From the viewpoint of further suppressing acid generation, the temperature of the alkaline aqueous solution is preferably 1°C or higher, more preferably 5°C or higher, and even more preferably 10°C or higher. From the viewpoint of preventing particle coarsening, the temperature of the alkaline aqueous solution is preferably 90°C or lower, more preferably 60°C or lower, and even more preferably 30°C or lower.

[0048] From the perspective of sufficient precipitation of the zinc phthalocyanine halide, the amount of the alkaline aqueous solution used is preferably 500 parts by mass or more, more preferably 800 parts by mass or more, and even more preferably 1000 parts by mass or more, relative to 100 parts by mass of the mixture containing the zinc phthalocyanine halide and the compound that reacts with water to generate an acid. From the perspective of utilizing high shear force to disaggregate the agglomerated particles, the amount of the alkaline aqueous solution used is preferably 5000 parts by mass or less, more preferably 3000 parts by mass or less, and even more preferably 2000 parts by mass or less, relative to 100 parts by mass of the mixture containing the zinc phthalocyanine halide and the compound that reacts with water to generate an acid.

[0049] The first step preferably further includes a post-treatment step of post-treating the precipitate after the precipitation step.

[0050] For example, the first step may further include a step of filtering the above-mentioned precipitate (the first post-treatment step). The first post-treatment step may be a step of filtering and washing the above-mentioned precipitate, or it may be a step of filtering, washing, and drying the above-mentioned precipitate. Washing can be carried out using, for example, an aqueous solvent such as water, sodium bisulfate water, sodium bicarbonate water, or sodium hydroxide water. In the washing, an organic solvent such as acetone, toluene, methanol, ethanol, or dimethylformamide can be used as needed. For example, washing with an organic solvent can be performed after washing with an aqueous solvent. Washing can be repeated multiple times (for example, 2 to 5 times). Specifically, it is preferred to wash until the pH of the filtrate is the same as the pH of the water used in washing (for example, the difference between the two is 0.2 or less).

[0051] For example, the first step may further include a step of dry grinding the above-mentioned precipitate (a second post-treatment step). Dry grinding can be performed in a grinder such as an attritor, a ball mill, a vibration mill, or a vibration ball mill. Dry grinding can be performed while heating (for example, while heating the grinder so that the temperature inside the grinder is 40°C to 200°C). Washing with water may also be performed after dry grinding. By washing with water after dry grinding (especially after dry grinding with an attritor), the amount of acid contained in the crude pigment can be further reduced. Washing may be any of water washing (washing with water below 40°C) and hot water washing (washing with water above 40°C). As with the first post-treatment step, washing is preferably performed until the pH of the filtrate is the same as the pH of the water used for washing (for example, the difference between the two is 0.2 or less). It should be noted that a treatment to improve the wettability of the precipitate (for example, a treatment in which the precipitate is brought into contact with a water-soluble organic solvent such as methanol) may be performed before or during washing with water. Dry grinding and washing can be repeated multiple times.

[0052] For example, the first step may further include a step of kneading the above-mentioned precipitate with water (a third post-treatment step). By performing the third post-treatment step, the amount of acid contained in the crude pigment can be further reduced. Kneading can be performed using, for example, a kneader, a sand mixer, etc. Kneading can be performed while heating. For example, the temperature of the water can be set to above 40°C. Inorganic salts can be added to the 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. An organic solvent (such as an organic solvent that can be used in the second step described later) can be used during kneading, but the amount of organic solvent used is preferably less than the amount of water used, and more preferably no organic solvent is used. After kneading, washing can be performed in the same manner as in the first post-treatment step. Kneading and washing can be repeated multiple times.

[0053] For example, the first step may further include a step (the fourth post-treatment step) of heating the precipitate in water (for example, boiling it). By performing the fourth post-treatment step, the amount of acid contained in the crude pigment can be further reduced. The heating temperature in the water can be, for example, above 40°C and below the boiling point, and the heating time can be, for example, 1 to 300 minutes. An organic solvent (for example, an organic solvent that can be used in the second step described later) can be mixed in the water, and the amount of the mixed organic solvent is preferably 20 parts by mass or less relative to 100 parts by mass of water. From the viewpoint of further removing the acid, in the fourth post-treatment step, the precipitate can be washed after being heated in water, or the precipitate can be washed after being heated in water, and the heating and washing in water can be repeated more than once (preferably more than twice). Washing can be performed in the same manner as in the first post-treatment step.

[0054] In this embodiment, two or more of the first to fourth post-treatment steps may be performed. When two or more of the first to fourth post-treatment steps are performed, their order is not particularly limited.

[0055] A zinc phthalocyanine halide crude pigment can be obtained through the above-mentioned first step. As mentioned above, in this embodiment, the above-mentioned precipitate obtained in the first step can be directly used as a zinc phthalocyanine halide crude pigment, or the material obtained by subjecting the above-mentioned precipitate to the above-mentioned post-treatment step (at least one of the first to fourth post-treatment steps) can be used as a zinc phthalocyanine halide crude pigment.

[0056] The crude zinc phthalocyanine halide pigment obtained in the first step contains one type or a plurality of types of zinc phthalocyanine halide having different numbers of halogen atoms.

[0057] In one embodiment, the average number of bromine atoms in the compound represented by one molecular formula (1) in the zinc phthalocyanine halide crude pigment is less than 13. The average number of bromine atoms may be 12 or less or 11 or less. The average number of bromine atoms may be 0.1 or more, 6 or more, or 8 or more. The above upper and lower limits may 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. It should be noted that, in the following similar descriptions, the upper and lower limits described separately may be arbitrarily combined.

[0058] When the average number of bromine atoms is less than 13, the average number of halogen atoms in one molecule of the compound represented by formula (1) in the crude zinc phthalocyanine halide pigment may be 14 or less, 13 or less, less than 13, or 12 or less. The average number of halogen atoms may be 0.1 or more, 8 or more, or 10 or more.

[0059] When the average number of bromine atoms is less than 13, the average number of chlorine atoms in one molecule of the compound represented by formula (1) in the crude zinc phthalocyanine halide pigment may be 5 or less, 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.

[0060] In another embodiment, the average number of bromine atoms in one molecule of the compound represented by formula (1) in the crude zinc phthalocyanine halide pigment is 13 or more. The average number of bromine atoms may be 14 or more, or 15 or less.

[0061] When the average number of bromine atoms is 13 or more, the average number of halogen atoms in the compound represented by formula (1) in the crude zinc phthalocyanine halide pigment may be 13 or more, 14 or more, or 15 or more. The average number of halogen atoms may be 16 or less, or 15 or less.

[0062] When the average number of bromine atoms is 13 or more, the average number of chlorine atoms per molecule of the compound represented by formula (1) in the crude zinc phthalocyanine halide pigment may be 0.1 or more or 1 or more. The average number of chlorine atoms may be 3 or less or less than 2.

[0063] The number of halogen atoms (e.g., the number of bromine atoms and the number of chlorine atoms) can be determined, for example, by mass analysis of a crude zinc phthalocyanine halide pigment using a matrix-assisted laser desorption ionization time-of-flight mass spectrometer (e.g., JMS-S3000 manufactured by JEOL Ltd.). Specifically, the number of each halogen atom can be calculated as a relative value per zinc atom from the mass ratio of zinc atoms to each halogen atom in the crude zinc phthalocyanine halide pigment.

[0064] The arithmetic standard deviation of the particle size distribution of the zinc phthalocyanine halide crude pigment is, for example, 15 nm or greater. The arithmetic standard deviation of the particle size distribution of the zinc phthalocyanine halide crude pigment is, for example, 1500 nm or less. If the arithmetic standard deviation of the particle size distribution of the zinc phthalocyanine halide crude pigment is within this range, finer pigment particles can be easily obtained. The arithmetic standard deviation of the particle size distribution of the zinc phthalocyanine halide crude pigment can be measured using a dynamic light scattering particle size distribution measuring apparatus. Specifically, the measurement can be performed using the following method and conditions.

[0065] <Method>

[0066] 2.48 g of a crude zinc phthalocyanine halide pigment, 1.24 g of BYK-LPN6919 manufactured by BYK-Chemie, 1.86 g of Unidic ZL-295 manufactured by DIC Corporation, and 10.92 g of propylene glycol monomethyl ether acetate were dispersed in a pigment shaker manufactured by Toyo Seiki Co., Ltd. using 0.3-0.4 mm zirconium beads for 2 hours to obtain a dispersion. After removing the zirconium beads using a nylon sieve, 0.02 g of the dispersion was diluted with 20 g of propylene glycol monomethyl ether acetate to obtain a dispersion for particle size distribution measurement.

[0067] <Conditions>

[0068] Measurement equipment: Dynamic light scattering particle size distribution analyzer LB-550 (manufactured by Horiba, Ltd.)

[0069] Measurement temperature: 25°C

[0070] ·Measurement sample: Dispersion for particle size distribution measurement

[0071] Data analysis conditions: particle size-based scattered light intensity, dispersion medium refractive index 1.402

[0072] The zinc phthalocyanine halide crude pigment obtained in this embodiment contains less acid than conventional crude pigments. Therefore, the pH of the zinc phthalocyanine halide crude pigment is, for example, 4.0 or greater. Here, the pH of the zinc phthalocyanine halide crude pigment can be confirmed by the following method: 5g of the zinc phthalocyanine halide crude pigment is mixed with 5g of methanol, and then further mixed with 100ml of ion-exchanged water. The resulting mixture is heated for 5 minutes to a boil, and then heated for another 5 minutes to maintain the boil. After the heated mixture is allowed to cool to below 30°C, the total amount of the mixture is adjusted to 100ml with ion-exchanged water, and then filtered. The pH of the resulting filtrate is measured at 25°C. From the perspective of easily obtaining finer pigment particles, the pH of the zinc phthalocyanine halide crude pigment is preferably 5.0 or greater, more preferably 5.5 or greater, further preferably 6.0 or greater, and particularly preferably 6.5 or greater. The pH of the zinc phthalocyanine halide crude pigment is, for example, 8.5 or less, and may also be 8.0 or less or 7.5 or less.

[0073] For example, in the case of using the compound containing aluminum halide in the fusion method, aluminum components such as aluminum hydroxide can be included in the thick pigment of zinc phthalocyanine sometimes. However, aluminum components may become the reason that contrast reduces, so the aluminum amount (Al amount) in the thick pigment of zinc phthalocyanine is as little as possible. From such a viewpoint, the Al amount contained by the thick pigment of zinc phthalocyanine is preferably below 3000 mass ppm, more preferably below 2000 mass ppm, further preferably below 1000 mass ppm. The Al amount contained by the thick pigment of zinc phthalocyanine can be obtained by high-frequency inductively coupled plasma emission spectrometry (ICP emission spectrometry). It should be noted that, in the precipitation process in the 1st operation, when using the alkaline aqueous solution of strong alkalinity, aluminum hydroxide can be dissolved and removed, therefore there is the tendency that can reduce the Al amount.

[0074] In the second step, for example, the crude zinc phthalocyanine halide pigment is kneaded and ground to be finer. Kneading can be performed using, for example, a kneader or a sand mixer.

[0075] The second step may be a step of kneading the zinc phthalocyanine halide crude pigment with an organic solvent, or a step of kneading the zinc phthalocyanine halide crude pigment with an inorganic salt and an organic solvent. Preferably, no water is used in the second step. The amount of water used is, for example, less than 20 parts by mass, less than 10 parts by mass, or less than 5 parts by mass relative to 100 parts by mass of the zinc phthalocyanine halide crude pigment.

[0076] In the organic solvent, a substance that does not dissolve the zinc phthalocyanine halide crude pigment and the inorganic salt can be used. As the organic solvent, it is preferred to use an organic solvent that can inhibit crystal growth. As such an organic solvent, a water-soluble organic solvent can be appropriately used. As the organic solvent, for example, diethylene glycol, glycerol, ethylene glycol, propylene glycol, liquid polyethylene glycol, liquid polypropylene glycol, 2-(methoxymethoxy) ethanol, 2-butoxyethanol, 2-(isopentyloxy) ethanol, 2-(hexyloxy) ethanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, etc. can be used. The amount of the organic solvent (such as a water-soluble organic solvent) used is not particularly limited, and is preferably 1 to 500 parts by mass relative to 100 parts by mass of the zinc phthalocyanine halide crude pigment.

[0077] In the second step, the crude zinc phthalocyanine halide pigment may be kneaded while being heated. To facilitate obtaining finer pigment particles, the heating temperature is preferably 40°C or higher, more preferably 60°C or higher, further preferably 80°C or higher, and particularly preferably 90°C or higher. For example, the heating temperature may be 150°C or lower.

[0078] The kneading time in the second step can be, for example, 1 to 60 hours.

[0079] When an inorganic salt and an organic solvent are used in the second step, a mixture containing a zinc phthalocyanine halide pigment, an inorganic salt and an organic solvent can be obtained. However, the organic solvent and the inorganic salt can be removed from the mixture, and the solid matter mainly containing the zinc phthalocyanine halide pigment can be washed, filtered, dried, pulverized, etc. as needed.

[0080] Washing can be done with water or hot water. Washing can be repeated 1 to 5 times. When using a water-soluble inorganic salt or a water-soluble organic solvent, the organic solvent and inorganic salt can be easily removed by washing with water. If necessary, acid washing, alkaline washing, or washing with an organic solvent can also be performed.

[0081] Drying after washing and filtration can be performed, for example, by heating the pigment at 80 to 120°C using a heat source provided in the dryer, for example, in a batch or continuous manner to dehydrate and / or remove the solvent. Typical dryers include box dryers, belt dryers, and spray dryers. Spray drying using a spray dryer is particularly preferred because it facilitates dispersion during paste preparation.

[0082] Pulverization after drying is not an operation to increase the specific surface area or reduce the average particle size of the primary particles. Instead, it is performed to disperse and powderize the pigment when the pigment forms a ramp shape, for example, when drying using a box dryer or a belt dryer. Examples of pulverization methods include mortars, hammer mills, disk mills, pin mills, and jet mills.

[0083] According to the above-mentioned production method, a fine zinc phthalocyanine halide pigment can be obtained. The present inventors speculate as follows regarding the reasons for this effect. First, when an acid is present during pigmentation, the acid promotes particle aggregation, thereby hindering the miniaturization of the pigment particles. On the other hand, in the above-mentioned production method, the acid is contained in the crude pigment and is suppressed, thus alleviating the above-mentioned effects caused by the acid. Therefore, using the above-mentioned method, a fine zinc phthalocyanine halide pigment can be obtained.

[0084] The zinc phthalocyanine halide pigment obtained by the above-mentioned manufacture method is suitable for use as a green pigment for color filters. Generally, there is a tendency that the smaller the particles of the pigment used in the pixel portion of the color filter, the higher the contrast and brightness. Therefore, when the zinc phthalocyanine halide pigment obtained by the above-mentioned manufacture method is used as a green pigment for color filters, there is a tendency to obtain excellent contrast, and in addition, there is a tendency to obtain excellent brightness.

[0085] The average particle size (average primary particle size) of the primary particles of the zinc phthalocyanine halogenide pigment obtained by the above method is, for example, less than 30 nm. According to the above method, for example, a zinc phthalocyanine halogenide pigment having an average primary particle size of less than 25 nm can also be obtained. The average primary particle size of the zinc phthalocyanine halogenide pigment can be more than 10 nm. Here, the average primary particle size is the average value of the major diameter of the primary particles, and can be obtained by measuring the major diameter of the primary particles in the same manner as the determination of the average aspect ratio described later.

[0086] The average aspect ratio of the primary particles of the zinc phthalocyanine halide pigment is, for example, 1.2 or greater, 1.3 or greater, 1.4 or greater, or 1.5 or greater. The average aspect ratio of the primary particles of the zinc phthalocyanine halide pigment is, for example, less than 2.0, 1.8 or less, 1.6 or less, or 1.4 or less. Zinc phthalocyanine halide pigments having such average aspect ratios can achieve even better contrast.

[0087] The zinc phthalocyanine halide pigment having an average primary particle aspect ratio within the range of 1.0 to 3.0 preferably contains no primary particles having an aspect ratio of 5 or greater, more preferably contains no primary particles having an aspect ratio of 4 or greater, and still more preferably contains no primary particles having an aspect ratio exceeding 3.

[0088] The aspect ratio and average aspect ratio of primary particles can be measured by the following method. First, the particles in the visual field are photographed using a transmission electron microscope (such as JEM-2010 manufactured by JEOL Ltd.). Then, the longer diameter (major diameter) and the shorter diameter (minor diameter) of the primary particles present in the two-dimensional image are measured, and the ratio of the major diameter to the minor diameter is set to the aspect ratio of the primary particles. In addition, for 40 primary particles, the average value of the major diameter and the minor diameter is obtained, and the ratio of the major diameter to the minor diameter is calculated using their values, which is used as the average aspect ratio. At this time, the zinc phthalocyanine halide pigment as a sample is dispersed in a solvent (such as cyclohexane) with a microscope after ultrasonic wave. In addition, a scanning electron microscope can also be used instead of a transmission electron microscope.

[0089] In the above-mentioned manufacturing method, the aggregation of the pigment can be suppressed. In addition, the primary particles of the pigment can be reduced, thereby increasing the surface area that can be adsorbed by the alkali. Therefore, in the above-mentioned manufacturing method, a zinc phthalocyanine halide pigment with a large amount of alkali adsorption can be obtained. In the dispersion of zinc phthalocyanine halide pigments, dispersants having basic functional groups (such as primary amino groups to tertiary amino groups) as adsorption groups for the pigment are widely used, but when the zinc phthalocyanine halide pigment has a large amount of alkali adsorption, the amount of these dispersants used can be reduced. Therefore, the use of zinc phthalocyanine halide pigments with a large amount of alkali adsorption can reduce the following undesirable conditions: dispersants with lower heat resistance than pigments decompose due to the heat of around 200°C applied when manufacturing color filters, thereby reducing contrast and brightness; dispersants are insoluble in developer, so the resolution and developability are reduced; and the color filter film is thickened due to the dispersant as a non-coloring component.

[0090] Furthermore, in the above-described production method, the use of a strongly alkaline aqueous solution in the precipitation step, such as in the melting method, can reduce the amount of Al contained in the crude zinc phthalocyanine halide pigment. Generally, the amount of Al remains constant during pigmentation, so there is a tendency to produce a zinc phthalocyanine halide pigment with a high alkali adsorption capacity and a low Al content from such a crude zinc phthalocyanine halide pigment with a low Al content. For example, a zinc phthalocyanine halide pigment with an alkali adsorption capacity of 0.13 mol / kg or more and an Al content of 3000 mass ppm or less can be obtained.

[0091] The alkali adsorption capacity of the zinc phthalocyanine halide pigment is preferably 0.13 mol / kg or more, more preferably 0.135 mol / kg or more, and even more preferably 0.140 mol / kg or more. The alkali adsorption capacity of the zinc phthalocyanine halide pigment can be 0.160 mol / kg or less. The alkali adsorption capacity is measured by the method described in the Examples.

[0092] The Al content in the zinc phthalocyanine halide pigment is preferably 3000 mass ppm or less, more preferably 2000 mass ppm or less, further preferably 1000 mass ppm or less, and particularly preferably less than 1000 mass ppm. The Al content in the zinc phthalocyanine halide pigment can be determined by high-frequency inductively coupled plasma optical emission spectrometry (ICP optical emission spectrometry).

[0093] Example

[0094] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited to the following examples.

[0095] <Example 1>

[0096] [Synthesis of crude pigment]

[0097] A 300 ml flask was charged with 91 g of sulfuryl chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 109 g of aluminum chloride (manufactured by Kanto Chemical Co., Ltd.), 15 g of sodium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.), 30 g of zinc phthalocyanine (manufactured by DIC Corporation), and 230 g of bromine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). The temperature was raised to 130° C. and maintained at 130° C. for 40 hours. The reaction mixture was extracted with 2500 g of a 10% by mass sodium hydroxide (NaOH) aqueous solution at a temperature of 15° C., filtered, washed with water, and dried to obtain a crude zinc phthalocyanine halide pigment (crude pigment A1). Washing was continued until the pH difference between the filtrate and the pH of the washing water was ±0.2.

[0098] Mass analysis of crude pigment A1 using a JMS-S3000 manufactured by JEOL Ltd. confirmed that the average number of chlorine atoms in the zinc phthalocyanine halide (P1) constituting crude pigment A1 was 1.8, and the average number of bromine atoms was 13.2. The mass analysis was performed with a delay time of 500 ns, a laser intensity of 44%, and a resolving power value of 32111 for peaks between m / z values ​​of 1820 and 1860.

[0099] [pH measurement of crude pigment A1]

[0100] In a 300ml beaker, 5g of crude pigment A1 and 5g of methanol were measured and mixed, and then 100ml of ion exchange water was further measured. The mixture was brought to a boil for 5 minutes using a hot stirrer and then continued to boil for 5 minutes. Next, the mixture was allowed to cool to below 30°C, and then transferred to a 100ml graduated cylinder. The total amount was adjusted to 100ml with ion exchange water and filtered. The pH and conductivity of the filtrate were measured. As a result, the pH of the crude pigment A1 at 25°C was 7.8, and the conductivity was 67μS / cm (micro-Siemens per centimeter). It should be noted that the pH was measured using a small, lightweight pH meter PH71 manufactured by Yokogawa Electric Corporation, and the conductivity was measured using a Seven Easy S30 manufactured by Mettler-Toledo Corporation.

[0101] [Determination of Al (Aluminum) Amount in Crude Pigment A1]

[0102] 0.25g of crude pigment A1 was mixed with 5ml of nitric acid, decomposed by microwave irradiation, and then fixed to 25ml with ion-exchanged water. Nitric acid was added to an aluminum standard solution for ICP emission spectrometry to the same degree as that used for pigment decomposition, and six samples of 0 mass ppm, 1000 mass ppm, 2000 mass ppm, 5000 mass ppm, 10000 mass ppm, and 100000 mass ppm were modulated to prepare a calibration curve. The Al content was measured using an ICP spectrometer (Perkin Elmer, Optima 4300DV) to create a calibration curve. A solution consisting of pigment decomposition products was also measured using an ICP spectrometer, and the Al content in the crude pigment A1 was calculated from the calibration curve. The result showed that the Al content was below 1000 mass ppm.

[0103] [Pigmentation]

[0104] 40 g of crude pigment A1, 400 g of ground sodium chloride, and 63 g of DEG (diethylene glycol) were placed in a double-arm kneader and kneaded at 80°C for 8 hours. The kneaded mixture was extracted with 2 kg of 80°C water and stirred for 1 hour. The mixture was then filtered, washed with hot water, dried, and ground to obtain green pigment G1.

[0105] [Measurement of average primary particle size]

[0106] Green pigment G1 was ultrasonically dispersed in cyclohexane and photographed with a microscope. The average particle size of the primary particles (average primary particle size) was calculated from the average value of 40 primary particles constituting the aggregates on the two-dimensional image. The average particle size of the primary particles was 24 nm.

[0107] [pH measurement of green pigment G1]

[0108] In a 300ml beaker, 5g of green pigment G1 and 5g of methanol were measured and mixed. 100ml of ion-exchanged water was then added and brought to a boil using a thermostilicate for 5 minutes. The mixture was then allowed to cool to below 30°C, transferred to a 100ml graduated cylinder, and the total volume was adjusted to 100ml with ion-exchanged water before filtration. The pH and conductivity of the filtrate were measured; the pH at 25°C was 7.6 and the conductivity was 59μS / cm.

[0109] [Determination of Al (Aluminum) Amount in Green Pigment G1]

[0110] The Al content in the green pigment G1 was calculated in the same manner as in the crude pigment A1 except that the green pigment G1 was used instead of the crude pigment A1. The Al content was 1000 ppm by mass or less.

[0111] [Determination of alkali adsorption amount]

[0112] Use automatic titrator COM-1700 (Hitachi High-Tech Corporation system) to measure the alkali adsorption capacity of green pigment G1.Particularly, at first, with modulation mixer (Conditioning mixer) about 0.1g green pigment G1 and 15mL absorption are mixed and stirred with alkaline solution (2000rpm, 3 minutes).After making green pigment G1 sedimentation by centrifugation (11000rpm, 20 minutes), take out 10mL supernatant, carry out the potentiometric titration of the liquid obtained by diluting it with n-propyl acetate (NPAC) 50mL, thereby measure the non-adsorbed alkali amount existing in the supernatant solution.From the alkali amount added, deduct the non-adsorbed alkali amount obtained, thereby calculate the alkali adsorption capacity on the green pigment G1.It should be noted that, use 0.001mol / L tetra-n-butylammonium hydroxide (TBAH) / NPAC solution as absorption with alkaline solution, use 0.001mol / L p-toluenesulfonic acid (PTSA) / NPAC solution as titration with acid solution.

[0113] [Evaluation of contrast and brightness]

[0114] 1.65 g of Pigment Yellow 138 (Chromofine Yellow 6206EC manufactured by Dainichi Seika Co., Ltd.), 3.85 g of DISPERBYK-161 (manufactured by BYK Chemicals), and 11.00 g of propylene glycol monomethyl ether acetate were dispersed together using 0.3-0.4 mm zirconium beads in a pigment shaker manufactured by Toyo Seiki Co., Ltd. for 2 hours to obtain a dispersion.

[0115] 4.0 g of the above dispersion, 0.98 g of Unidic ZL-295, and 0.22 g of propylene glycol monomethyl ether acetate were added and mixed using a pigment shaker to obtain a yellow composition for coloring (TY1).

[0116] 2.48 g of the green pigment G1 obtained in Example 1, 1.24 g of BYK-LPN6919 manufactured by BYK-Chemie, 1.86 g of Unidic ZL-295 manufactured by DIC Corporation, and 10.92 g of propylene glycol monomethyl ether acetate were dispersed together using 0.3 to 0.4 mm zirconium beads in a pigment shaker manufactured by Toyo Seiki Co., Ltd. for 2 hours to obtain a pigment dispersion for color filter (MG1).

[0117] 4.0 g of the color filter pigment dispersion (MG1), 0.98 g of Unidic ZL-295 manufactured by DIC Corporation, and 0.22 g of propylene glycol monomethyl ether acetate were added and mixed using a pigment shaker to obtain an evaluation composition (CG1) for forming a green pixel portion for a color filter.

[0118] Evaluation composition (CG1) was spin-coated on a soda-lime glass substrate, dried at 90°C for 3 minutes, and then heated at 230°C for 1 hour. This produced a glass substrate for contrast evaluation having a colored film on the soda-lime glass substrate. The spin speed during spin coating was adjusted so that the thickness of the colored film obtained by heating at 230°C for 1 hour was 1.8 μm.

[0119] Furthermore, a coating solution obtained by mixing the yellow toning composition (TY1) and the evaluation composition (CG1) prepared above was spin-coated on a soda-lime glass substrate, dried at 90°C for 3 minutes, and then heated at 230°C for 1 hour. A glass substrate for brightness evaluation having a colored film on the soda-lime glass substrate was thus produced. By adjusting the mixing ratio of the yellow toning composition (TY1) and the evaluation composition (CG1) and the rotation speed during spin coating, a colored film having a chromaticity (x, y) of (0.275, 0.570) under illuminant C, obtained by heating at 230°C for 1 hour, was produced.

[0120] The contrast of the colored film on the glass substrate for contrast evaluation was measured using a contrast meter CT-1 manufactured by Tsubosaka Electric Co., Ltd., and the brightness of the colored film on the glass substrate for brightness evaluation was measured using a U-3900 manufactured by Hitachi High-Technologies Corporation. The results are shown in Table 1. The contrast and brightness shown in Table 1 are based on the contrast and brightness of Comparative Example 1.

[0121] <Examples 2 and 3>

[0122] During the synthesis of crude pigment, as extracting solution, use sodium acetate (CH3COONa) aqueous solution or sodium bicarbonate (NaHCO3) aqueous solution instead of sodium hydroxide aqueous solution, in addition, operate similarly to Example 1, obtain crude pigment A2 and A3. With JEOL Ltd. system JMS-S3000, crude pigment A2 and A3 are carried out mass analysis, and the result confirms that any crude pigment is all made of the zinc phthalocyanine halide (P1) that average chlorine number is 1.8, average bromine number is 13.2 and constitutes. In addition, operate similarly to Example 1, measure the pH of crude pigment A2 and A3 and the Al amount in specific conductivity and crude pigment A2 and A3. The results are shown in Table 1.

[0123] Use crude pigment A2 or A3 to replace crude pigment A1 respectively, otherwise, operate in the same manner as in Example 1 to obtain green pigments G2 and G3. In addition, operate in the same manner as in Example 1 to measure the average primary particle size, pH, electrical conductivity, Al amount and alkali adsorption capacity of green pigments G2 and G3. In addition, use green pigment G2 or G3 to replace green pigment G1, otherwise, operate in the same manner as in Example 1 to make a glass substrate for contrast evaluation and a glass substrate for brightness evaluation, and measure contrast and brightness. The results are shown in Table 1.

[0124] <Examples 4 to 8>

[0125] When synthesizing the crude pigment, the concentration of the sodium hydroxide aqueous solution used as the extract was changed to the value shown in Table 1. The same operation as in Example 1 was performed to obtain crude pigments A4 to A8. Mass analysis of crude pigments A4 to A8 using a JMS-S3000 manufactured by JEOL Ltd. confirmed that each crude pigment consisted of a zinc phthalocyanine halide (P1) having an average chlorine number of 1.8 and an average bromine number of 13.2. Furthermore, the pH and electrical conductivity of crude pigments A4 to A8, as well as the amount of Al in crude pigments A4 to A8, were measured in the same manner as in Example 1. The results are shown in Table 1.

[0126] Green pigments G4 to G8 were obtained by the same procedure as in Example 1 except that crude pigments A4 to A8 were used instead of crude pigment A1. Furthermore, the average primary particle size, pH, conductivity, Al content, and alkali adsorption capacity of green pigments G4 to G8 were measured in the same manner as in Example 1. Furthermore, glass substrates for contrast evaluation and glass substrates for brightness evaluation were produced in the same manner as in Example 1 except that green pigments G4 to G8 were used instead of green pigment G1, and the contrast and brightness were measured. The results are shown in Table 1.

[0127] <Examples 9 and 10>

[0128] During the synthesis of crude pigment, the temperature of the aqueous sodium hydroxide solution as the extract was changed to the value shown in Table 1. In addition, the same operation as in Example 1 was performed to obtain crude pigments A9 and A10. Using JEOL Ltd.'s JMS-S3000, crude pigments A9 and A10 were mass analyzed. The results confirmed that any crude pigment consisted of a zinc phthalocyanine halide (P1) having an average chlorine number of 1.8 and an average bromine number of 13.2. Furthermore, the pH and electrical conductivity of crude pigments A9 and A10, as well as the Al content of crude pigments A9 and A10, were measured by the same operation as in Example 1. The results are shown in Table 1.

[0129] Use crude pigment A9 or A10 instead of crude pigment A1, otherwise, operate in the same manner as in Example 1 to obtain green pigments G9 and G10. In addition, operate in the same manner as in Example 1 to measure the average primary particle size, pH, conductivity, Al amount and alkali adsorption capacity of green pigments G9 and G10. In addition, use green pigment G9 or G10 instead of green pigment G1, otherwise, operate in the same manner as in Example 1 to make a glass substrate for contrast evaluation and a glass substrate for brightness evaluation, and measure contrast and brightness. The results are shown in Table 1.

[0130] <Examples 11 and 12>

[0131] Green pigments G11 and G12 were obtained in the same manner as in Example 1, except that the heating temperature and / or mixing time during the mixing process in the pigmentation step were changed as shown in Table 1. Furthermore, the average primary particle size, pH, conductivity, Al content, and alkali adsorption capacity of green pigments G11 and G12 were measured in the same manner as in Example 1. Furthermore, glass substrates for contrast evaluation and glass substrates for brightness evaluation were produced in the same manner as in Example 1, except that green pigments G11 or G12 were used instead of green pigment G1, and the contrast and brightness were measured. The results are shown in Table 1.

[0132] <Comparative Examples 1 and 2>

[0133] During the synthesis of crude pigment, the hydrochloric acid (HCl aqueous solution) of water or concentration 10% by mass was used to replace the aqueous sodium hydroxide solution as the extracting solution. In addition, the same operation as in Example 1 was performed to obtain crude pigments A13 and A14. Using JEOL Ltd.'s JMS-S3000, crude pigments A13 and A14 were mass analyzed. The results confirmed that any crude pigment consisted of 1.8 zinc phthalocyanine halides (P1) with an average chlorine number of 13.2 and an average bromine number of 13.2. In addition, the same operation as in Example 1 was performed to measure the pH and specific conductivity of crude pigments A13 and A14 and the Al amount in the crude pigments A13 and A14. The results are shown in Table 1.

[0134] Using crude pigment A13 or A14 instead of crude pigment A1, otherwise, the same operation as in Example 1 was carried out to obtain green pigments G13 and G14. In addition, the same operation as in Example 1 was carried out to measure the average primary particle size, pH, conductivity, Al amount and alkali adsorption capacity of green pigments G13 and G14. In addition, using green pigment G13 or G14 instead of green pigment G1, otherwise, the same operation as in Example 1 was carried out to make a glass substrate for contrast evaluation and a glass substrate for brightness evaluation, and measure contrast and brightness. The results are shown in Table 1.

[0135] <Example 13>

[0136] A 300 ml flask was charged with 90 g of sulfuryl chloride (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 105 g of aluminum chloride (manufactured by Kanto Chemical Co., Ltd.), 14 g of sodium chloride (manufactured by Tokyo Chemical Industry Co., Ltd.), 27 g of zinc phthalocyanine (manufactured by DIC Corporation), and 55 g of bromine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). The temperature was raised to 130° C. and maintained at 130° C. for 40 hours. The reaction mixture was extracted with 2500 g of a 10% by mass sodium hydroxide (NaOH) aqueous solution at a temperature of 15° C., filtered, washed with water, and dried to obtain a crude zinc phthalocyanine halide pigment (crude pigment A15). Washing was performed until the pH of the filtrate reached the same pH as the water used for washing.

[0137] Mass analysis of crude pigment A15 using a JMS-S3000 manufactured by JEOL Ltd. confirmed that the average number of chlorine atoms in the zinc phthalocyanine halide (P2) constituting crude pigment A15 was 2.9, and the average number of bromine atoms was 9.3. The delay time during mass analysis was 510 ns, the laser intensity was 40%, and the resolving power value for peaks between m / z = 1820 and 1860 was 65086. Furthermore, the pH and electrical conductivity of crude pigment A15, as well as the Al content in crude pigment A16, were measured in the same manner as in Example 1. The results are shown in Table 2.

[0138] Use thick pigment A15 to replace thick pigment A1, in addition, operate similarly to Example 1, obtain green pigment G15.In addition, operate similarly to Example 1, measure average primary particle diameter, pH, specific conductivity, Al amount and alkali adsorption capacity of green pigment G15.In addition, use Pigment Yellow 185 (BASF company's system Paliotol Yellow D1155) to replace Pigment Yellow 138 (Dainichi Seika Co., Ltd.'s system Chromofine Yellow 6206EC), use green pigment G15 to replace green pigment G1, and the chromaticity (x, y) of tinted film is adjusted to (0.230, 0.670), in addition, operate similarly to Example 1, make contrast evaluation glass substrate and luminance evaluation glass substrate, measure contrast and luminance.Results are shown in Table 2.

[0139] Comparative Example 3

[0140] When synthesizing the crude pigment, water was used instead of the aqueous sodium hydroxide solution as the extract. Otherwise, the same operation as in Example 13 was carried out to obtain crude pigment A16. Using JEOL Ltd.'s JMS-S3000 mass analysis of crude pigment A16, it was confirmed that each crude pigment consisted of a zinc phthalocyanine halide (P2) having an average chlorine number of 2.9 and an average bromine number of 9.3. Furthermore, the pH and electrical conductivity of crude pigment A16, as well as the Al content in crude pigment A16, were measured in the same manner as in Example 13. The results are shown in Table 2.

[0141] Using crude pigment A16 instead of crude pigment A15, otherwise, the same operation as in Example 13 was carried out to obtain green pigment G16. In addition, the average primary particle size, pH, conductivity, Al amount and alkali adsorption capacity of green pigment G17 were measured in the same manner as in Example 13. In addition, using green pigment G16 instead of green pigment G15, otherwise, the same operation as in Example 13 was carried out to produce a glass substrate for contrast evaluation and a glass substrate for brightness evaluation, and to measure contrast and brightness. The results are shown in Table 2.

[0142] [Table 1]

[0143]

[0144] [Table 2]

[0145]

Claims

1. A method for producing a zinc phthalocyanine halide pigment, comprising: A process for synthesizing zinc phthalocyanine halide using a compound that generates an acid by reacting with water; a step of extracting the mixture containing the compound and the zinc phthalocyanine halide obtained in the step in an alkaline aqueous solution and precipitating the zinc phthalocyanine halide to obtain a crude zinc phthalocyanine halide pigment; and The step of pigmenting the zinc phthalocyanine halide crude pigment, The compound that reacts with water to generate an acid is selected from chlorosulfonic acid, aluminum halide, titanium halide, alkaline (earth) metal halide, thionyl chloride, sulfuryl chloride, The alkaline aqueous solution contains at least one alkaline compound selected from the group consisting of sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, calcium bicarbonate, sodium acetate, potassium acetate, and calcium acetate. 2 . The production method according to claim 1 , wherein the concentration of the basic compound contained in the alkaline aqueous solution is 1% by mass or more. The production method according to claim 1 or 2, wherein the temperature of the alkaline aqueous solution is 5 to 90°C. The production method according to claim 1 or 2, wherein the pH of the crude zinc phthalocyanine halide pigment is 5.0 or higher. The production method according to claim 1 or 2, wherein the amount of Al contained in the crude zinc phthalocyanine halide pigment is 1000 mass ppm or less. A zinc phthalocyanine halide pigment obtained by the production method according to any one of claims 1 to 5, wherein the pigment has an average primary particle size of 10 nm to 30 nm, an alkali adsorption capacity of 0.140 mol / kg to 0.160 mol / kg, and an Al content of 1000 mass ppm or less.

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