JP2023088862A - Method for treating pigment - Google Patents

Abstract

To provide a method for treating pigment, which obtains pigment having good optical density, transparency, and dispersion stability.SOLUTION: A method for treating pigment, comprises: a first step of putting pigment, a dispersion aid, and a liquid medium to a rotor-stator processing machine and carrying out a crushing treatment of the pigment to prepare a pigment dispersion having a pH of 3.0-11.0; and a second step of carrying out a precipitation treatment on the pigment dispersion to prepare a wet cake of treated pigment particles or solid treated pigment particles, which are coated with the dispersion aid. Note that the rotor-stator processing machine is preferably an in-line type processing machine into which the pigment, the dispersion aid, and the liquid medium are continuously fed.SELECTED DRAWING: Figure 1

Description

The present invention relates to a pigment treatment method.

Dyes and pigments are used as coloring agents for printing inks and paints, and pigments are widely used from the viewpoint of fastness. In order to obtain good transparency and optical density in printed matter and coated matter using pigments as colorants, it is necessary to disperse the pigments finely and uniformly in the medium, and to maintain the dispersion state stably. be. In particular, in the field of ink jet recording and the field of color filters, where excellent transparency and optical density are required, it is necessary to highly disperse pigments with a small average primary particle size. However, as the average primary particle size of the pigment becomes smaller, the cohesive force between the pigments becomes stronger, making it difficult to finely disperse and stabilize the dispersion.
In order to solve these problems, many approaches have been studied, such as mitigation of aggregation by surface modification of pigment particles.

JP-A-9-031360 JP-A-9-104834

However, it has been difficult for pigment dispersions obtained by conventional processing methods to satisfy all requirements of optical density, transparency and dispersion stability.

An object of the present invention is to provide a pigment treatment method for obtaining a pigment having good optical density, transparency and dispersion stability.

In the pigment treatment method of the present invention, the first step is to prepare a pigment suspension having a pH of 3.0 to 11.0 by pulverizing the pigment, dispersing aid and liquid medium with a rotor-stator processor, followed by the pigment. a second step of settling the suspension to produce a wet cake or solid treated pigment particles coated with a dispersing aid.

According to the present invention, it is possible to provide a pigment treatment method for obtaining a pigment having good optical density, transparency and dispersion stability.

FIG. 1 is a schematic cross-sectional view showing an example of a rotor-stator processing machine. FIG. 2 is a schematic side view showing an example of a rotor-stator processing machine. FIG. 3 is a schematic cross-sectional view for explaining crushing processing in a rotor-stator processing machine. FIG. 4 is a schematic external view of a rotor-stator processing machine in the crushing process. FIG. 5 is a schematic diagram showing an example of an in-line rotor-stator processing machine.

Terms used herein are defined. "(Meth)acryloyl", "(meth)acryl", "(meth)acrylic acid", "(meth)acrylate", or "(meth)acrylamide", unless otherwise specified, respectively " acryloyl and/or methacryloyl”, “acrylic and/or methacrylic”, “acrylic acid and/or methacrylic acid”, “acrylate and/or methacrylate”, or “acrylamide and/or methacrylamide”. "C.I." means a color index (C.I.). Moreover, "disaggregation" means loosening aggregates. Moreover, "monofunctional" refers to a compound having only one polymerizable group in one molecule. The terms "bifunctional" and "trifunctional" refer to compounds having two or three polymerizable groups in one molecule, respectively, and bifunctional or higher functional compounds are collectively referred to as "polyfunctional." Moreover, "EO" refers to "ethylene oxide", and "PO" refers to "propylene oxide".

The present invention is a pigment treatment method comprising the following steps.
The pigment, dispersing aid and liquid medium are crushed by a rotor-stator processor to prepare a pigment suspension having a pH of 3.0 to 11.0. A second step of making a wet cake or solid treated pigment particles of treated pigment particles coated with a dispersing aid.

<Pigment>
An inorganic pigment or an organic pigment can be appropriately selected as the pigment used in the present invention. Examples of inorganic pigments include carbon black, metal oxides, metal complex salts, and other inorganic pigments. Examples of carbon black include furnace black, thermal lamp black, acetylene black, channel black and the like. Examples of metal oxides include titanium oxide, iron oxide, iron hydroxide, zirconia, and alumina. Examples of other inorganic pigments include ultramarine blue, yellow lead, zinc sulfide, and cobalt blue. Organic pigments include, for example, diketopyrrolopyrrole-based pigments, anthraquinone-based pigments, quinacridone-based pigments, dioxazine-based pigments, perinone-based pigments, perylene-based pigments, thiazineindigo-based pigments, triazine-based pigments, benzimidazolone-based pigments, benzo Indole pigments such as isoindole, isoindoline pigments, isoindolinone pigments, quinophthalone pigments, naphthol pigments, threne pigments, metal complex pigments, azo pigments such as azo, disazo and polyazo. be done.

When referring to organic pigments in terms of color index, for example, C.I. I. Pigment Red
1, 2, 3, 4, 5, 6, 7, 9, 10, 14, 17, 22, 23, 31, 32, 38, 41, 48:1, 48:2, 48:3, 48:4, 49, 49:1, 49:2, 52:1, 52:2, 53:1, 57:1, 60:1, 63:1, 66, 67, 81:1, 81:2, 81:3, 83, 88, 90, 105, 112, 119, 122, 123, 144, 146, 147, 148, 149, 150, 155, 166, 168, 169, 170, 171, 172, 175, 176, 177, 178, 179, 184, 185, 187, 188, 190, 200, 202, 206, 207, 208, 209, 210, 216, 220, 224, 226, 242, 246, 254, 255, 264, 266, 269, 270, 272, 279;
C. I. Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 24, 31, 32, 34, 35, 35: 1, 36, 36:1, 37, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 86, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 123, 125, 126, 127, 128, 129, 137, 138, 139, 147, 148, 150, 151, 152, 153
, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188 , 193, 194, 199, 213, 214;
C. I. Pigment Orange 2, 5, 13, 16, 17: 1, 31, 34, 36, 38, 43, 46, 48, 49, 51, 52, 55, 59, 60, 61, 62, 64, 71, 73;
C. I. Pigment Green 7, 10, 36, 37, 58, 59, 62, 63;
C. I. Pigment Blue 1, 2, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 22, 60, 64, 66, 79, 79, 80;
C. I. Pigment Violet 1, 19, 23, 27, 32, 37, 42;
C. I. Pigment Brown 25, 28;
C. I. Pigment Black 1, 7 and the like.

Pigments can be used singly, as a mixture containing two or more, or as a solid solution. Solid solution refers to a mode in which X-ray diffraction of a composite pigment containing two pigments shows the crystal lattice of one pigment (host) and the other pigment (guest) is buried in the crystal lattice of the host component. .

When the pigment is an organic pigment, the total content of free polyvalent metal ions and atoms in the pigment measured by ICP emission spectrometry in accordance with Japanese Industrial Standards JIS K 0116; 2014 must be 50,000 ppm or less. It is preferably 30,000 ppm or less, and more preferably 30,000 ppm or less. Polyvalent metals include, for example, calcium, aluminum, magnesium, chromium, copper, iron, nickel and the like. In the case of an organic pigment having a metal in the pigment molecular skeleton, for example, the pigment is immersed in dilute hydrochloric acid, subjected to extraction treatment, and the resulting extract is subjected to ICP emission spectroscopic analysis to determine free polyvalent metals in the pigment. The total content of ions and atoms can be calculated.

As the pigment, a wet cake-like pigment containing water or a dry-pulverized powdery pigment can be used. From the viewpoint of the pigment pulverization treatment efficiency, it is preferable to use a wet cake-like pigment.

<Dispersing aid>
Dispersing aids of the present invention are resins, surfactants or dye derivatives. A dispersing aid can be used individually or in combination of 2 or more types.

Resins are, for example, rosins or rosin derivatives such as disproportionated rosins, hydrogenated rosins, fumarated rosins, maleated rosins, ester gums, polymerized rosins, rosin esters, rosin-modified phenolic resins; Chain low density polyethylene (L-LDPE), polyethylene such as low density polyethylene (LDPE), polyolefin resin such as polypropylene; polyester resin such as polyethylene terephthalate; polyvinyl chloride, phenolic resin, natural modified phenolic resin, natural resin modified malein Acid resin, polyvinyl acetate, silicone resin, polyurethane resin, polyamide resin, epoxy resin, xylene resin, polyvinyl butyral, terpene resin, coumarone-indene resin, alkyd resin, amino resin, epoxy resin, petroleum resin, and modified resins thereof ; styrene-(meth)acrylic acid copolymer, (meth)acrylic acid-(meth)acrylic acid alkyl ester copolymer, styrene-(meth)acrylic acid-(meth)acrylic acid alkyl ester copolymer, styrene- α-methylstyrene-(meth)acrylic acid copolymer, styrene-α-methylstyrene-(meth)acrylic acid-(meth)acrylic acid alkyl ester copolymer, polyacrylic acid, polymethacrylic acid, vinylnaphthalene-( meth)acrylic acid copolymer, styrene-(anhydride) maleic acid copolymer, maleic acid-maleic anhydride copolymer, vinyl naphthalene-(anhydride) maleic acid copolymer, α-olefin-(anhydride) maleic acid copolymer Examples include polymers, α-olefin-maleic acid alkyl ester copolymers, resins having acid groups such as polyester-modified acrylic acid polymers, acrylic copolymers and salts thereof.

Among them, resins having hydrophobic sites such as linear, branched or cyclic hydrocarbon chains, aromatic rings, or heterocyclic rings are preferable. preferable. Moreover, resins having an anionic group are preferred, resins having a carboxyl group are more preferred, and resins having a (meth)acrylic acid structure or a maleic acid structure are even more preferred. Alternatively, a resin having a cationic group instead of an anionic group can be used, and a resin having an amino group or pyridine structure is preferred.

The amount of the resin used is preferably 0.1 to 200 parts by mass, more preferably 1 to 100 parts by mass, per 100 parts by mass of the pigment.

A resin having an acid group such as (meth)acrylic acid or maleic acid can control the solubility in a liquid medium such as water or an organic solvent by salting the acid group portion. Examples of the compound capable of forming a salt with the resin include basic compounds such as inorganic bases and organic bases.
Examples of inorganic bases include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide; alkali metal salts of silicic acid such as sodium orthosilicate, sodium metasilicate and sodium sesquisilicate; alkali metal salts of phosphoric acid, alkali metal salts of carbonic acid such as disodium carbonate, sodium hydrogencarbonate and dipotassium carbonate, alkali metal salts of boric acid such as sodium borate, ammonia;
Examples of organic bases include alkylamines such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine and triethylamine, aminoethanol, methylaminoethanol, dimethylaminoethanol, ethylaminoethanol, butylaminoethanol, diethylaminoethanol, dibutylaminoethanol, Examples include alkanolamines such as diethanolamine and triethanolamine, and amines having nonionic groups such as methoxypoly(oxyethylene/oxypropylene)-2-propylamine.

A basic compound can be used individually or in combination of 2 or more types.

A resin having a basic group such as an amino group or a pyridine ring can control the solubility in a liquid medium such as water or an organic solvent by salting the base portion. Compounds capable of forming salts with resins include, for example, acidic compounds such as inorganic acids and organic acids.
Inorganic acids include sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, hydrochloric acid, nitric acid, phosphoric acid, boric acid and their aqueous solutions; Organic acids include formic acid, acetic acid, dichloroacetic acid, propionic acid, butyric acid, valeric acid, caproic acid, Saturated fatty acids such as enanthic acid, caprylic acid, pelargonic acid, capric acid and lauric acid; unsaturated fatty acids such as oleic acid, linoleic acid and linolenic acid; hydroxy acids such as lactic acid, malic acid and citric acid; benzoic acid and phthalic acid , isophthalic acid, terephthalic acid, salicylic acid, gallic acid, mellitic acid, cinnamic acid; dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid; tricarboxylic acids such as aconitic acid; oxocarboxylic acids such as vilpic acid and oxaloacetic acid; organic acids other than those mentioned above such as methanesulfonic acid;

An acidic compound can be used individually or in combination of 2 or more types.

Surfactants include, for example, anionic, nonionic or amphoteric surfactants.

Anionic surfactants include, for example, fatty acid salts, alkylsulphate salts, alkylarylsulphonates, alkylnaphthalenesulphonates, alkylsulphates, dialkylsulphonates, dialkylsulphosuccinates, alkyldiaryletherdisulphonates, Alkyl phosphate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl aryl ether sulfate, naphthalene sulfonic acid formalin condensate, polyoxyethylene alkyl ether phosphate, polyoxyethylene alkyl phosphate, glycerol borate Fatty acid esters, polyoxyethylene glycerol fatty acid esters and the like can be mentioned.

Examples of amphoteric surfactants include betaines, sulfobetaines, alkylbetaines, alkylamine oxides and the like.

Nonionic surfactants include, for example, polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, polyoxyethyleneoxypropylene block copolymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid Examples include esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, and the like.

The amount of surfactant used is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass, based on 100% by mass of the pigment.

A dye derivative is a compound having an acidic group, a basic group, a neutral group, or the like in an organic dye residue. Dye derivatives include, for example, compounds having an acidic substituent such as a sulfo group, a carboxy group, and a phosphoric acid group, amine salts thereof, compounds having a basic substituent such as a sulfonamide group or a terminal tertiary amino group A compound having a neutral substituent such as a phenyl group or a phthalimidoalkyl group can be mentioned.
Organic dyes include, for example, diketopyrrolopyrrole pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, perinone pigments, perylene pigments, thiazineindigo pigments, triazine pigments, benzimidazolone pigments, benzoiso Indole pigments such as indole, isoindoline pigments, isoindolinone pigments, quinophthalone pigments, naphthol pigments, threne pigments, metal complex pigments, azo pigments such as azo, disazo and polyazo. .

The amount of the dye derivative used is preferably 0.1 to 50% by mass, more preferably 0.5 to 20% by mass, based on 100% by mass of the pigment.

Water or an organic solvent can be used as the liquid medium of the present invention. Water is, for example, ion-exchanged water, distilled water, or the like. Organic solvents include, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, methoxypropanol, methoxybutanol, 1-ethoxy-2-propanol, 2 -(methoxymethoxy)ethanol, 2-butoxyethanol, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol, glycerin, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, Alcohol-based solvents such as triethylene glycol monomethyl ether, liquid polyethylene glycol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, liquid polypropylene glycol, butyl glycol, butyl diglycol; acetone, methyl ethyl ketone, methyl isobutyl ketone , cyclohexanone and other ketone solvents; tetrahydrofuran, 1,4-dioxane and other ether solvents; dimethyl sulfoxide, hexamethylene sulfoxide, sulfolane and other sulfoxide solvents; ethyl acetate, acetic acid-n-butyl, ethyl lactate and other ester solvents Solvent; amide solvents such as N,N-dimethylformamide and 1-methyl-2-pyrrolidone; aromatic hydrocarbon solvents such as toluene and xylene; aliphatic hydrocarbon solvents such as hexane and octane; nitriles such as acetonitrile system solvents; halogen solvents such as carbon tetrachloride and dichloromethane; and ionic liquids such as 1-ethyl-3-methylimidazolium tetrafluoroborate. From the viewpoint of filtering and washing the pigment particles coated with the dispersing aid, it is preferable to use water or water-soluble organic solvents such as alcohol solvents, ketone solvents, sulfoxide solvents, and amide solvents as the liquid medium. It is particularly preferred to use water or alcoholic solvents.

A liquid medium can be used individually or in combination of 2 or more types.

The amount of the liquid medium used is preferably 100 to 10,000 parts by mass, more preferably 200 to 3,000 parts by mass, and particularly preferably 200 to 1,200 parts by mass, based on 100 parts by mass of the pigment. By using an appropriate amount of the liquid medium within a range in which the viscosity of the pigment suspension does not increase too much, the efficiency of the disintegration treatment of the pigment is improved, and fine and uniform treatment of the dispersing aid becomes possible. As a result, a fine and uniform dispersion particle size distribution can be realized as a pigment dispersion, thereby improving optical density and transparency.

The combination of the dispersing aid and the liquid medium can be appropriately selected according to the type of pigment to be treated and the intended use of the treated pigment particles coated with the dispersing aid.

In the pigment treatment method of the present invention, the pigment, dispersing aid and liquid medium are crushed by a rotor-stator treatment machine.
The coating efficiency of the dispersing aid on the pigment can be improved. That is, by dispersing treated pigment particles finely and uniformly coated with a dispersing aid, a finely and uniformly dispersed pigment dispersion can be obtained. This provides excellent optical density, transparency and dispersion stability.

A rotor-stator processing machine includes a rotor having rotatable blades and a stator having a wall disposed on the outer peripheral side of the blades. It is a device that pulverizes pigment particles by applying a shearing force to the pigment particles between a rotor and a stator. The rotors and stators can be of any shape available on the market, and different shapes or the same shape can be used in combination.

FIG. 1 is a schematic cross-sectional view showing an example of a rotor-stator processing machine. The rotor-stator processor 100 comprises a central shaft 10 , a rotor 20 and a stator 30 . Examples of the constituent materials of the central shaft 10, the rotor 20 and the stator 30 include metallic materials and ceramics.

The central shaft 10 is an elongate member and extends, for example, in the vertical direction. Assuming that the vertical direction is the Z-axis, FIG. 1(a) is a cross-sectional view along the XY plane, and FIG. 1(b) is a cross-sectional view along the XZ plane. The central shaft 10 supports a rotor 20 and a stator 30 respectively.

The rotor 20 has an annular (for example, annular) blade portion 22 extending in the longitudinal direction of the central shaft 10 at the outer peripheral portion of the rotor 20, and a connecting portion 24 connecting the blade portion 22 and the central shaft 10. there is The blade portion 22 can rotate around the central axis 10 . The blade portion 22 has openings (through holes) 22a passing through the blade portion 22. For example, the blade portion 22 has a plurality of openings 22a at intervals (e.g., equal intervals) along the circumferential direction. ing. The opening direction of the opening 22a may be inclined with respect to the radial direction. The vertically upper end of the opening 22a may be left open without the members forming the rotor 20 being disposed thereon. The number, arrangement and shape of the openings 22a are not particularly limited.

The arrangement and shape of the blades in the rotor of the rotor-stator processor are not particularly limited. For example, the blade portion is not limited to an annular member arranged on the outer periphery of the rotor, and may have a shape extending from the center to the outer periphery of the rotor. The rotor may have a plurality of blades shaped to extend from the center to the periphery of the rotor. The shape of the blades extending from the center to the outer periphery of the rotor may be streamlined.

The stator 30 has an annular (for example, annular) wall portion 32 extending in the longitudinal direction of the central shaft 10 at the outer peripheral portion of the stator 30 and a connecting portion 34 connecting the wall portion 32 and the central shaft 10 . there is The wall portion 32 is arranged on the outer peripheral side of the blade portion 22 in the rotor-stator processing machine 100 . The wall portion 32 has openings (through holes) 32a penetrating the wall portion 32. For example, the wall portion 32 has a plurality of openings 32a at intervals (e.g., equal intervals) along the circumferential direction. ing. The opening direction of the opening 32a may be inclined with respect to the radial direction.

The number, arrangement and shape of the wall openings in the stator are not particularly limited. FIG. 2 is a schematic side view showing an example of a stator (stator wall portion) in a rotor-stator processing machine. Examples of the wall portion of the stator include a wall portion (FIG. 2A) having openings arranged in an array (for example, rectangular openings such as square openings), and a plurality of rectangular openings arranged in a row. A wall portion having an opening (FIG. 2(b)), a wall portion having a plurality of circular (for example, perfectly circular) openings arranged in a row (FIG. 2(c)), and the like can be mentioned. Examples of the shape of the opening include a rectangular shape (square shape, rectangular shape, etc.), a circular shape (perfect circle shape, elliptical shape, etc.), and the like.

The stator may have a plurality of annular (eg, toric) walls extending longitudinally of the central axis at the outer periphery of the stator. For example, the stator may include the wall portion 32 described above as a first wall portion, and may include a second wall portion disposed on the outer peripheral side of the first wall portion in the rotor-stator type processing machine. A third wall portion arranged on the outer peripheral side of the second wall portion in the processor may be further provided. The number of wall portions is not particularly limited, and may be four or more.

FIG. 3 is a schematic diagram for explaining pulverization processing or crushing processing in the rotor-stator processing machine, and is a schematic cross-sectional view showing an enlarged part of the outer peripheral portion of the rotor-stator processing machine 100 shown in FIG. is. In the rotor-stator processing machine 100, for example, after a pigment suspension consisting of a pigment, a dispersing aid and a liquid medium is supplied around the central shaft 10, the pigment suspension is transferred to the rotor as shown in FIG. It reaches the space between the blade portion 22 and the wall portion 32 of the stator 30 via the opening 22a of the blade portion 22 of 20 (flow path F1 in the figure). In this space, the pigment particles P (non-volatile matter) are pulverized by a shearing force caused by the rotational motion of the blade portion 22 . After that, part of the crushed particles flows out to the outer peripheral side of the wall part 32 through the opening 32a of the wall part 32 (flow path F2 in the figure), and the rest of the particles flows into the blade part 22 and the wall. The particles are further crushed by the shearing force as they further progress through the space between the portion 32 . As a result, the pigment component in the pigment suspension is crushed by the crushing treatment of the rotor-stator processor 100 .
FIG. 4 is a schematic diagram for explaining the crushing process together with the appearance of the rotor-stator processing machine. As shown in FIG. 4( a ), the pigment particles P are supplied around the central axis 10 . Next, the pigment particles P are pulverized in the space between the rotor 20 and the stator 30 as shown in FIG. 4(b). Next, as shown in FIG. 4C, the crushed pigment particles P' flow out to the outer peripheral side of the wall portion 32. Next, as shown in FIG.

The shear force exerted by the processing section consisting of the rotor and stator is expressed in shear rate (shear rate). The shear rate [s ⁻¹ ] can be obtained by dividing the peripheral speed [m/s] of the rotor blades by the distance [m] between the blades and the stator wall. The shear rate is preferably from 10,000 to 500,000 s ^-1 , more preferably from 20,000 to 200,000 s ^-1 , particularly preferably from 30,000 to 100,000 s ^-1 , and most preferably from 40,000 to 80,000 s ^-1 , from the viewpoint of pigment pulverization efficiency. If the shear rate is low, the pigment will not be sufficiently pulverized and the coating with the dispersing aid will be insufficient, resulting in poor dispersibility. On the other hand, when treated with an excessive shear rate, the pigment is pulverized excessively, the dispersing aid for coating the pigment is insufficient, and the dispersion stability tends to deteriorate.

The distance between the blade portion and the wall portion of the stator is preferably 0.10 to 10 mm, more preferably 0.15 to 3 mm, from the viewpoint of suppressing pigment clogging during processing and processing efficiency.

The peripheral speed of the blades of the rotor can be appropriately selected from the range of 1 to 100 m/s, depending on the distance between the blades and the wall of the stator, in order to obtain the desired shear rate.

The rotor-stator type processing machine may have a plurality of processing units (crushing units) composed of rotors and stators. By flowing the pigment suspension from the low shear rate processing section to the high shear rate processing section, clogging can be easily suppressed, and the pigment can be pulverized efficiently. The rotor-stator processing machine may have a plurality of processing sections (may have multiple processing sections) along a vertically extending central axis. When the rotor-stator type processing machine has a plurality of processing sections along the central axis, it is preferable to dispose processing sections having a higher shear rate downward in the vertical direction from the viewpoint of facilitating efficient crushing of coarse particles.

As the rotor-stator processor, an in-line rotor-stator processor (hereinafter referred to as "in-line processor") can be used. In the in-line processing machine, the pigment suspension is continuously supplied, and for example, the processing machine can be installed in the middle of the processing route (for example, piping) to continuously pulverize the pigment suspension. In the in-line processor, the entire pigment suspension is forced through the processor, so the batch rotor-stator processor (hereinafter referred to as "batch processor") processes mainly only the area around the rotor. can uniformly treat the entire pigment suspension compared to the case of using only Therefore, compared to using a batch processor, treated pigment particles processed with an in-line processor can result in finer and more uniformly dispersed pigment dispersions, resulting in better optical densities. , transparency and dispersion stability can be obtained.

FIG. 5 is a schematic diagram showing an example of an in-line processor. The pigment particles P supplied to the processing section through the pipe 40 are pulverized in the space between the rotor 20 and the stator 30 and discharged to the pipe 50 . As a result, the entire pigment suspension is continuously passed through the processor, thus enabling uniform processing.

In an in-line processor, the pigment suspension may be circulated.

As a rotor-stator type processing machine, IKA's equipment name "magic LAB" (in-line type, maximum peripheral speed: 41 m / s, maximum rotation speed: 26000 rpm); Shear in-line mixer, in-line type, maximum peripheral speed: 20 m / s, maximum rotation speed: 10000 rpm); equipment name “L5M-A” manufactured by Silverson Nippon Co., Ltd. (batch type, maximum peripheral speed: 20 m / s, maximum rotation speed : 10000 rpm). As a processor manufactured by IKA, a processor equipped with a UTR module (ULTRA-TURRAX), a DR module (DISPAX-REACTOR), an MK module, an MKO module and a CMX module can be used. The DR module has three stages of processing units (stages) composed of rotors and stators, and since the shear rate can be adjusted by the combination of the rotors and stators, the pigment can be efficiently pulverized easily. For example, by using 2P/4M/6F processing units in order from the top in the vertical direction, it is possible to arrange processing units with higher share rates toward the bottom in the vertical direction.

The pH of the pigment suspension in the first step of the present invention is 3.0-11.0. When using a dispersing aid having an anionic group, under strongly basic conditions with a pH higher than 11.0, the solubility of the dispersing aid in the liquid medium becomes excessive and the affinity of the dispersing aid for the pigment decreases. descend. On the other hand, when a dispersing aid having a cationic group is used, the affinity of the dispersing aid for the pigment is similarly reduced under strongly acidic conditions at a pH of less than 3. As a result, the dispersing aid does not adsorb to the pigment crushed in the first step, resulting in a decrease in coating efficiency, difficulty in fine and uniform treatment, and deterioration in dispersion quality. Preferred pH is 4.0 to 10.0, more preferred pH is 5.0 to 9.0.

In the present invention, known acidic compounds and basic compounds can be used for the purpose of adjusting the pH of the pigment suspension in the first step or controlling the solubility of the dispersing aid. Examples of acidic compounds include inorganic acids such as sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, hydrochloric acid, nitric acid, phosphoric acid, boric acid, and aqueous solutions thereof; organic acids such as formic acid, acetic acid, dichloroacetic acid, propionic acid, butyric acid, Saturated fatty acids such as valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid and lauric acid; unsaturated fatty acids such as oleic acid, linoleic acid and linolenic acid; hydroxy acids such as lactic acid, malic acid and citric acid Aromatic carboxylic acids such as benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid, mellitic acid, cinnamic acid; oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, maleic acid dicarboxylic acids such as acids; tricarboxylic acids such as aconitic acid; oxocarboxylic acids such as birupic acid and oxaloacetic acid; organic acids other than those mentioned above such as methanesulfonic acid; Basic compounds include, for example, alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide, alkaline earth metal hydroxides such as calcium hydroxide and magnesium hydroxide, sodium orthosilicate and sodium metasilicate. , alkali metal salts of silicic acid such as sodium sesquisilicate; alkali metal salts of phosphoric acid such as trisodium phosphate; alkali metal salts of carbonic acid such as disodium carbonate, sodium hydrogen carbonate and dipotassium carbonate; Alkali metal salts of acids, ammonia; alkylamines such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, aminoethanol, methylaminoethanol, dimethylaminoethanol, ethylaminoethanol, butylaminoethanol, diethylaminoethanol, dibutylamino Alkanolamines such as ethanol, diethanolamine and triethanolamine, and organic bases such as amines having nonionic groups such as methoxypoly(oxyethylene/oxypropylene)-2-propylamine. However, as described above, from the viewpoint of adsorption of the dispersing aid to the pigment, strong acids such as sulfuric acid and hydrochloric acid having an acid dissociation constant (pKa) of 3 or less, alkali metal hydroxides, and alkaline earth metal hydroxides The use of such strong bases is less preferred. Therefore, it is preferable to use formic acid, acetic acid, and phosphoric acid as acidic compounds, and ammonia, alkylamines, and alkanolamines as basic compounds for adjusting the pH of the pigment suspension or controlling the solubility of the dispersing aid.

The temperature during the pigment crushing treatment in the first step is preferably 0 to 80°C, more preferably 0 to 60°C. Under high-temperature conditions, the surface energy of the pigment particles increases, making it easier for the pigments to agglomerate, resulting in poor pulverization treatment efficiency.

The present invention comprises a second step of precipitating the pigment suspension obtained in the first step to produce a wet cake or solid treated pigment particles coated with a dispersing aid. The precipitation treatment method for a pigment suspension includes, for example, a so-called acid precipitation method or a salting-out method in which an acidic compound or a basic compound is added to insolubilize or precipitate the dispersing aid to fix the dispersing aid to the pigment. mentioned. Alternatively, a method of fixing the dispersing aid to the pigment by insolubilizing or precipitating the dispersing aid by distilling off part or all of the liquid medium, a method of depositing or precipitating the dispersing aid by contact with a poor solvent, Examples thereof include a method of sedimenting a pigment suspension by centrifugation. Among them, the acid precipitation method or the salting out method is preferable from the viewpoint of excellent dispersion stability and suppression of angle dependence of hue.

The angular dependence of hue is the degree to which scattered light close to the complementary color of the original color is observed when the angle of the light source striking the print and the angle of observation are changed. As can be observed, it is desirable that this angular dependence be low. The inventors have found that the angular dependence of the hue of printed matter can be suppressed by using an acid precipitation method or a salting-out method when precipitating a pigment suspension.

According to the study by the inventors, the difference in the effect depending on the precipitation method is that when the pigment suspension is precipitated by distilling off the solvent, the polar group ends are spread out and precipitated, so the ends of the resin are entangled with other particles. It is presumed that some of these particles remain as coarse particles during dispersion, diffusely reflecting light, and causing a change in hue depending on the viewing angle. On the other hand, when the pigment suspension is precipitated by the acid precipitation method or the salting-out method, the polar group ends of the resin lose charge repulsion and gather near the pigment particles, making it possible to reduce coarse particles and reduce scattered light. it is conceivable that. Therefore, from the viewpoint of the angle dependence of the hue, the method for precipitating the pigment suspension is preferably the acid precipitation method or the salting out method.

Acidic compounds that can be used in the acid precipitation method include inorganic acids such as sulfuric acid, oleum, chlorosulfonic acid, hydrochloric acid, nitric acid, phosphoric acid, boric acid; formic acid, acetic acid, dichloroacetic acid, propionic acid, butyric acid, valeric acid, capron Saturated fatty acids such as acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, and lauric acid; unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid; hydroxy acids such as lactic acid, malic acid, and citric acid; Aromatic carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid, mellitic acid and cinnamic acid; dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, fumaric acid and maleic acid acids; tricarboxylic acids such as aconitic acid; oxocarboxylic acids such as vilpic acid and oxaloacetic acid; and organic acids other than those mentioned above such as methanesulfonic acid. These acidic compounds can also be used as aqueous solutions.

Basic compounds that can be used in the salting-out method include, for example, alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide and magnesium hydroxide; alkali metal salts of silicic acid such as sodium silicate, sodium metasilicate and sodium sesquisilicate; alkali metal salts of phosphoric acid such as trisodium phosphate; alkali metal salts of carbonate such as disodium carbonate, sodium hydrogen carbonate and dipotassium carbonate; Alkali metal salts of boric acid such as sodium borate, ammonia; alkylamines such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine and triethylamine, aminoethanol, methylaminoethanol, dimethylaminoethanol, ethylaminoethanol, butylaminoethanol , alkanolamines such as diethylaminoethanol, dibutylaminoethanol, diethanolamine and triethanolamine, and organic bases such as amines having nonionic groups such as methoxypoly(oxyethylene/oxypropylene)-2-propylamine. These basic compounds can also be used as aqueous solutions.

The amount of the acidic compound or basic compound used in the acid precipitation method or salting-out method is preferably 1 to 5000 parts by mass, more preferably 50 to 1000 parts by mass, per 100 parts by mass of the dispersing aid.

The method of adding the acidic compound or basic compound is not particularly limited as long as the method allows the dispersing aid to precipitate or settle and the pigment suspension to settle. Examples thereof include a method of directly adding an acidic compound or a basic compound to a pigment suspension, a method of adding a pigment suspension to an aqueous solution of an acidic compound or a basic compound, and the like.

In the method of adding an acidic compound or a basic compound directly to a pigment suspension, unprecipitated or unprecipitated pigment and dispersing aid components are incorporated into previously deposited or precipitated pigment and dispersing aid aggregates. This may hinder the complete precipitation of the pigment suspension, resulting in deterioration of the workability of the filtration step, which will be described later, and deterioration of the dispersion stability of the pigment dispersion. Therefore, in the method of adding the acidic compound or basic compound directly to the pigment suspension, it is preferable to add the acidic compound or basic compound while applying a shearing force to the pigment using a rotor-stator processing machine. From the viewpoint of uniform and complete precipitation of the pigment suspension, a method of adding the pigment suspension to an aqueous solution of an acidic compound or a basic compound is more preferable. It is preferable to use 10 to 1000% by mass of the aqueous solution of the acidic compound or the basic compound with respect to 100% by mass of the pigment suspension.

The wet cake of treated pigment particles coated with a dispersing aid obtained in the second step of the present invention is obtained by filtering and washing the precipitated pigment suspension with water, and It means the water content of the treated pigment particles. The moisture content in the wet cake is 30-90% by mass. Filtration and washing with water are generally performed using a filter press or Nutsche, and a filter press is preferably used industrially. When using a filter press, air blowing or squeezing may be performed as necessary to control the moisture content of the wet cake.

From the viewpoint of increasing the efficiency of filtration and washing, the pigment suspension may be subjected to a heat treatment after the pigment suspension is precipitated in the second step and before filtration. The heating temperature is preferably 40 to 90° C., and the heating time is preferably 5 minutes to 3 hours.

The solid treated pigment particles coated with dispersing aid obtained in the second step of the present invention can be obtained by drying a precipitation treated pigment suspension or a wet cake of treated pigment particles. A method known in the art can be used for drying, and examples thereof include a normal pressure drying method using an oven, a vacuum drying method, a spray drying method, and the like. The drying temperature in the normal pressure drying method using an oven is 30 to 150°C, preferably 40 to 100°C. The water content in the solid treated pigment particles after drying is 0.01 to 5 mass %.

Solid treated pigment particles are generally pulverized into a powder form to improve handleability. The equipment used for pulverization is not particularly limited, but ball mills, bead mills, colloid mills, conical mills, disc mills, edge mills, milling mills, hammer mills, mortars, pellet mills, VSI mills, Willy mills, roller mills, jet A known device such as a mill can be used.

The present invention may comprise a third step of dispersing the wet cake of treated pigment particles or the solid treated pigment particles and the dispersing medium to form a pigment dispersion.

<Dispersion medium>
Dispersion media are resins and solvents. The dispersion medium can be appropriately selected according to the application of the pigment dispersion.
Dispersion media can be broadly classified into water-based media in which water is the main component, and oil-based media in which the main component is other than water.
Applications of pigment dispersions include, for example, resin compositions for molding, moldings, paints for building materials and automobiles, printing inks (e.g., letterpress printing inks used for letterpress printing, flexographic printing, UV flexographic printing, gravure printing, etc.) , intaglio printing ink used for UV gravure printing, etc., lithographic printing ink used for offset printing, UV offset printing, etc., stencil printing ink used for screen printing, etc., inkjet printing, UV inkjet printing, electrostatic charge development toner printing ink for on-demand printing), ink for writing utensils, color filters, solid-state imaging devices, sensors such as LiDAR, and the like.
Pigment dispersions are preferably prepared by mixing a wet cake of treated pigment particles or solid treated pigment particles with a dispersing medium and dispersing according to methods known in the art.

Dispersion processing includes, for example, horizontal sand mill, vertical sand mill, annular bead mill, attritor, microfluidizer, high-speed mixer, homomixer, homogenizer, high-pressure homogenizer, ball mill, paint shaker, roll mill, stone mill, and ultrasonic dispersion. machine, high-pressure disperser, opposing collision disperser, oblique collision disperser, and the like. In addition, dispersers and mixers that are commonly used for preparing various dispersions in the art can be appropriately selected and used.

In addition, before dispersion, pre-dispersion using a kneader, a kneading mixer such as a three-roll mill, or non-volatile dispersion treatment using a two-roll mill or the like may be performed. In addition, after dispersing with various dispersers, a post-treatment of storing in a heated state of 30 to 80 ° C. for several hours to about a week, and a post-treatment process using an ultrasonic disperser or a collision type beadless disperser. is effective for imparting dispersion stability to the pigment dispersion.

The ratio of the treated pigment particles to the dispersing medium is preferably 0.001 to 0.7 times by weight, more preferably 0.01 to 0.6 times by weight of the pigment particles per 100 parts by weight of the dispersing medium.

The resin as the dispersion medium may be, for example, polyolefin resin, polyester resin, styrene copolymer, acrylic resin, and modified resins thereof. Specifically, polyethylene such as high density polyethylene (HDPE), linear low density polyethylene (L-LDPE), low density polyethylene (LDPE), polyolefin resin such as polypropylene; polyester resin such as polyethylene terephthalate; styrene-p -chlorostyrene copolymer, styrene-vinyltoluene copolymer, styrene-vinylnaphthalene copolymer, styrene-acrylic acid ester copolymer, styrene-methacrylic acid ester copolymer, styrene-α-methyl chloromethacrylate copolymer Polymer, styrene-acrylonitrile copolymer, styrene-vinyl methyl ether copolymer, styrene-vinyl ethyl ether copolymer, styrene-vinyl methyl ketone copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer , Styrene copolymers such as styrene-acrylonitrile-indene copolymers; Acrylic resins such as acrylic resins and methacrylic resins; Resins, polyurethanes, polyamide resins, epoxy resins, xylene resins, polyvinyl butyral, terpene resins, coumarone-indene resins, alkyd resins, amino resins, epoxy resins, petroleum resins, and modified resins thereof.

The solvent as the dispersion medium may be water, an aromatic hydrocarbon-based organic solvent, an aliphatic hydrocarbon-based organic solvent, or a polymerizable monomer. Specifically, water such as ion-exchanged water and distilled water; aromatic hydrocarbon organic solvents such as toluene and xylene; aliphatic hydrocarbon organic solvents such as acetate organic solvents, ketone organic solvents, and alcohol organic solvents; Solvents may be mentioned. More specifically, acetate organic solvents such as butyl acetate and methyl acetate; ketone organic solvents such as methyl ethyl ketone and methyl isobutyl ketone; ethanol, n-propanol, isopropanol, n-butanol, isobutanol, ethylene glycol, diethylene glycol, Triethylene glycol, propylene glycol, methoxypropanol, methoxybutanol, 1-ethoxy-2-propanol, 2-(methoxymethoxy)ethanol, 2-butoxyethanol, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol , glycerin, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, liquid polyethylene glycol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, liquid Alcohol-based organic solvents such as polypropylene glycol, butyl glycol, and butyl diglycol are included.

A polymerizable monomer has a function of causing a polymerization or a cross-linking reaction by an initiating species such as a radical and curing a composition containing them. Polymerizable monomers include (meth)acrylate compounds, vinyl ether compounds, compounds having a (meth)acrylate group and a vinyl ether group, allyl compounds, N-vinyl compounds, unsaturated carboxylic acids and the like.

Monofunctional (meth)acrylate compounds include, for example, benzyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, (ethoxylated (or propoxylated)) 2-phenoxyethyl (meth)acrylate, dicyclopentenyl (oxyethyl) (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2-(2-ethoxyethoxy) ethyl (meth) ) acrylate, methoxydipropylene glycol (meth) acrylate, dipropylene glycol (meth) acrylate, nonylphenol EO-modified acrylate, nonylphenol PO-modified acrylate, o-phenylphenol EO-modified acrylate, 2-ethylhexyl EO-modified acrylate, β-carboxylethyl ( meth)acrylate, trimethylolpropane formal (meth)acrylate, isoamyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth) acrylate, isononyl (meth) acrylate, stearyl (meth) acrylate, n-octyl acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, isodecyl (meth) acrylate, tridecyl (meth) acrylate, caprolactone (meth) acrylates, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 1,4-cyclohexanedimethanol (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl ( meth)acrylate, acryloylmorpholine, N-acryloyloxyethylhexahydrophthalimide and the like.

Monofunctional N-vinyl compounds include, for example, N-vinylcaprolactam, N-vinylpyrrolidone, N-vinylformamide and the like.

Difunctional (meth)acrylates are, for example, 1,6-hexanediol di(meth)acrylate, ethoxylated (or propoxylated) 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate. ) acrylate, neopentyl glycol di(meth)acrylate, 2,4-dimethyl-1,5-pentanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, butylethylpropanediol (meth)acrylate, ethoxylated cyclohexanemethanol di(meth)acrylate, polyethylene glycol di(meth)acrylate, oligoethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 2- Ethyl-2-butylbutanediol di(meth)acrylate, neopentylglycol hydroxypivalate di(meth)acrylate, EO-modified bisphenol A di(meth)acrylate, bisphenol F polyethoxydi(meth)acrylate, polypropylene glycol di(meth)acrylate , oligopropylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 2-ethyl-2-butylpropanediol di(meth)acrylate, 1,9-nonane di(meth)acrylate, propoxylated ethoxy bisphenol A di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, ethoxylated bisphenol F di(meth)acrylate, isocyanuric acid EO-modified diacrylate, tricyclodecanedi (Meth) acrylate, dipropylene glycol di(meth) acrylate, tripropylene glycol di(meth) acrylate, PO-modified neopentyl glycol di(meth) acrylate, EO-modified neopentyl glycol di(meth) acrylate dimethyloltricyclodecanedi (Meth)acrylate, cyclohexanedimethanol di(meth)acrylate, trimethylolpropane di(meth)acrylate, neopentyl glycol-modified trimethylolpropane di(meth)acrylate, dicyclopentanyl di(meth)acrylate and the like.

Trifunctional (meth)acrylates include, for example, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, alkylene oxide-modified tri(meth)acrylate of trimethylolpropane (e.g., trimethylolpropane EO-modified tri acrylate, trimethylolpropane PO-modified triacrylate, etc.), tetramethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, trimethylolpropane tri((meth)acryloyloxypropyl) Ether, isocyanuric acid alkylene oxide-modified tri(meth)acrylate, dipentaerythritol propionate tri(meth)acrylate, tri((meth)acryloyloxyethyl) isocyanurate, hydroxypivalaldehyde-modified dimethylolpropane tri(meth)acrylate, Sorbitol tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, ethoxylated glycerin triacrylate, propoxylated glyceryl triacrylate and the like.

Tetrafunctional (meth)acrylates are, for example, pentaerythritol tetra(meth)acrylate, sorbitol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol propionate tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, tetramethylolmethane tetra(meth)acrylate and the like.

Examples of pentafunctional (meth)acrylates include sorbitol penta(meth)acrylate and dipentaerythritol penta(meth)acrylate.

Hexafunctional (meth)acrylates include, for example, dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, alkylene oxide-modified hexa(meth)acrylate of phosphazene, ε-captolactone-modified dipentaerythritol hexa(meth) acrylates and the like.

Compounds having a (meth)acryloyl group and a vinyl ether group (bifunctional or higher polymerizable monomers) include 2-(2-vinyloxyethoxy)ethyl acrylate, 2-(2-vinyloxyethoxy)ethyl methacrylate, and the like. be done.

A solvent can be used individually or in combination of 2 or more types.

[Dye derivative]
The pigment dispersion can contain the dye derivative. Inclusion of a dye derivative improves the dispersion stability of the treated pigment particles.

A dye derivative can be used individually or in combination of 2 or more types.

The pigment dispersion can contain known materials such as dispersants and polymerization inhibitors.

The pigment dispersion obtained in the present invention can be used for various coloring applications, such as resin compositions for molding, moldings, paints for building materials and automobiles, printing inks (e.g., letterpress printing, flexographic printing, UV flexographic printing, etc.). Relief printing ink used, gravure printing, intaglio printing ink used for UV gravure printing, etc., planographic printing ink used for offset printing, UV offset printing, etc., stencil printing ink used for screen printing, etc., inkjet printing, UV inkjet printing , ink for on-demand printing used in electrostatic charge development toner printing), ink for writing instruments, color filters, solid-state imaging devices, sensors such as LiDAR, and the like.

EXAMPLES The present invention will be described below based on examples, but the present invention is not limited by these. In the examples and comparative examples, "part" means "mass part" and "%" means "mass%".

(Synthesis Example 1) Synthesis of copper phthalocyanine pigment P-1 140.0 parts of crude copper phthalocyanine [p-1] synthesized with reference to the method described in Example 1 of JP-A-10-310717 was mixed with 1120 parts of 98% sulfuric acid. After dissolving at 70° C., it was added dropwise to 9000 parts of water to precipitate. After filtration and washing with distilled water, the resulting wet cake was dispersed in 9000 parts of water and adjusted to pH 8-10 with a 25% sodium hydroxide aqueous solution. This was heated to 80° C. and stirred for 1 hour. Then, it was filtered, washed with distilled water, dried at 80° C. and pulverized to obtain 135.5 parts of copper phthalocyanine pigment [P′-1].

Then, 120.0 parts of the obtained copper phthalocyanine pigment [P'-1] was added to 1200 parts of diethylene glycol, and the mixture was heated and stirred at 120° C. for 3 hours. After that, it was filtered, washed with hot water, dried at 80° C. and pulverized to obtain 114.3 parts of copper phthalocyanine pigment [P″-1].

Next, 100 parts of the copper phthalocyanine pigment [P''-1], 1200 parts of sodium chloride, and 120 parts of diethylene glycol are charged in a stainless steel 1-gallon kneader (manufactured by Inoue Seisakusho), kneaded at 120 ° C. for 6 hours, and salted. processed by milling. The resulting kneaded product was put into 10,000 parts of hot water, stirred for 1 hour while heating to 70° C. to form a slurry, filtered and washed repeatedly to remove sodium chloride and diethylene glycol, and 98 parts of copper phthalocyanine pigment [P 245 parts of a wet cake (40% non-volatile content) containing [-1] was obtained.

(Synthesis Example 2) Synthesis of Acrylic Urethane Resin Emulsion 1 Acrylic urethane resin emulsion 1 (34% non-volatile content) was obtained with reference to the methods described in Synthesis Example 4 and Synthesis Example 5 of JP-A-2019-203051.

(Synthesis Example 3) Synthesis of phthalocyanine compound 1 A phthalocyanine compound 1 (laurylamine salt of copper phthalocyanine sulfonic acid) was obtained with reference to the method described in JP-A-57-12067.

(Synthesis Example 4) Synthesis of phthalocyanine compound 2 Phthalocyanine compound 2 ({N-[3-(diethylamino)propyl]sulfamoyl}copper phthalocyanine) was obtained with reference to the method described in Japanese Patent Publication No. 57-15620.

(Synthesis Example 5) Preparation of diketopyrrolopyrrole pigment C.I. I. 100 parts of Pigment Orange 73 (DPP Orange SJ1C manufactured by CINIC) was added little by little to 1000 parts of stirred 98% sulfuric acid and completely dissolved by stirring at 20°C for 4 hours. Next, the sulfuric acid solution was added dropwise to 1200 parts of stirred ice water to precipitate the pigment composition. This was filtered and washed with ion-exchanged water, and the obtained wet cake was reslurried in 600 parts of a 0.1% aqueous sodium hydroxide solution, further filtered, washed with ion-exchanged water, and a wet cake containing diketopyrrolopyrrole pigment 1 was obtained. was made. The wet cake had a non-volatile content of 35% by mass.

(Synthesis Example 6) Preparation of resin solution 1 With reference to the method described in Resin (C-1) of JP-A-2022-158049, a methacrylic acid block polymer (number average molecular weight (Mn): 6,000, acid value 169 mg KOH /g) was obtained.
An acid value equivalent of dimethylaminoethanol and water were added to this polymer to obtain a resin solution 1 having a solid content of 25%.

(Synthesis Example 7) Preparation of Resin Solution 2 With reference to the method described in Resin (C-5) of JP-A-2022-158049, methacrylic acid random polymer (number average molecular weight (Mn): 11,900, acid value 252 mg KOH/g) was obtained.
An acid value equivalent of dimethylaminoethanol and water were added to this polymer to obtain a resin solution 2 having a solid content of 25%.

(Synthesis Example 8) Preparation of Resin Solution 3 With reference to the method described in Resin (C-6) of JP-A-2022-158049, acrylamide random polymer (number average molecular weight (Mn): 12,100, acid value 130 mgKOH /g) was obtained.
An acid value equivalent of dimethylaminoethanol and water were added to this polymer to obtain a resin solution 3 having a solid content of 25%.

(Synthesis Example 9) Preparation of Resin Solution 4 With reference to the method described in Resin (C-9) of JP-A-2022-158049, an α-olefin maleic acid random polymer (number average molecular weight (Mn): 8,100, An acid value of 162 mgKOH/g) was obtained.
An acid value equivalent of dimethylaminoethanol and water were added to this polymer to obtain a resin solution 4 having a solid content of 25%.

<Treatment Pigment Particles>
(Example 1) Production of Treated Pigment Particles 1 As the first step, C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 200 parts, styrene-acrylic acid copolymer as a dispersion aid (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34%) 29.4 parts, as a liquid medium 2857 parts of distilled water was added to prepare a mixed solution of pH=8. A rotor-stator processing machine (manufactured by Silverson Nippon Co., Ltd., equipment name: VERSO, square hole high shear screen, in-line type, distance between the blade part and the wall part of the stator: 0.24 mm) connected by piping from the bottom discharge valve. Using a shear rate of 62000 s ^-1 (rotation speed 7500 rpm, peripheral speed 14.9 m / s), the mixed liquid was subjected to circulation pulverization treatment at 40 ° C. for 1 hour to prepare a pigment suspension of pH = 8. .

In the second step, 62.5 parts of 80% acetic acid was added dropwise over 30 minutes to the obtained pigment suspension while circulating it with a Silverson processor to precipitate the pigment suspension. , filtration and washing with water to obtain a wet cake of treated pigment particles 1 coated with a dispersing aid. The wet cake was dried at 80° C. for 24 hours and pulverized to obtain 205.8 parts of solid processed pigment particles 1.

(Example 2) Production of Treated Pigment Particles 2 The procedure of Example 1 was repeated except that 25% aqueous ammonia was added so that the pH of the mixed solution in the first step was 10. 206.9 parts of solid treated pigment particles 2 got The pH of the pigment suspension in the first step was 10.

(Example 3) Production of Treated Pigment Particles 3 The procedure of Example 1 was repeated except that the temperature during the circulation pulverization treatment in the first step was changed from 40°C to 80°C. got The pH of the pigment suspension in the first step was 8.

(Example 4) Production of Treated Pigment Particles 4 Performed except that the shear rate during the circulation crushing treatment in the first step was changed from 62000 s ^-1 to 25000 s ^-1 (rotation speed 3000 rpm, peripheral speed 6.0 m/s) Example 1 was repeated to obtain 205.8 parts of solid treated pigment particles 4. The pH of the pigment suspension in the first step was 8.

(Example 5) Production of Treated Pigment Particles 5 Except for changing the shear rate during the circulation pulverization treatment in the first step from 62000 s ^-1 to 83000 s ^-1 (rotation speed 10000 rpm, peripheral speed 19.9 m/s) Example 1 was repeated to obtain 5 206.9 parts of solid treated pigment particles. The pH of the pigment suspension in the first step was 8.

(Example 6) Production of Treated Pigment Particles 6 As the first step, C.I. I. Pigment Red
122 (manufactured by Clariant Japan, Toner Magenta E) 200 parts, styrene-acrylic acid copolymer as a dispersion aid (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) 29.4 parts, distilled water as a liquid medium 2857 parts were added to prepare a mixed solution of pH=8. A rotor-stator processing machine (manufactured by Silverson Nippon Co., Ltd., equipment name: VERSO, square hole high shear screen, in-line type, distance between the blade part and the wall part of the stator: 0.24 mm) connected by piping from the bottom discharge valve. Using a shear rate of 62000 s ^-1 (rotation speed 7500 rpm, peripheral speed 14.9 m / s), the mixed liquid was subjected to circulation pulverization treatment at 40 ° C. for 1 hour to prepare a pigment suspension of pH = 8. .

As a second step, an acidic aqueous solution at 25° C. was prepared separately from 2765 parts of distilled water and 62.5 parts of 80% acetic acid. While this acidic aqueous solution is being stirred, the pigment suspension obtained in the first step is dropped over 30 minutes to perform a precipitation treatment of the pigment suspension. A wet cake of treated pigment particles 6 coated with was obtained. The wet cake was dried at 80° C. for 24 hours and pulverized to obtain 204.8 parts of solid processed pigment particles 6.

(Example 7) Production of Treated Pigment Particles 7 C.I. I. Pigment Red (manufactured by Clariant Japan, Toner Magenta E) 122 200 parts, styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34%) 29.4 parts, distilled water 2857 parts, . I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34%) 44.1 parts, distilled water 2000 parts , in the same manner as in Example 6 except that 2765 parts of distilled water and 62.5 parts of 80% acetic acid in the second step were changed to 1862 parts of distilled water and 93.8 parts of 80% acetic acid. .7 copies were obtained. At this time, the pH of the pigment suspension in the first step was 8.

(Example 8) Production of Treated Pigment Particles 8 Same as Example 7 except that 1862 parts of distilled water and 93.8 parts of 80% acetic acid in the second step were changed to 1742 parts of distilled water and 214.3 parts of 35% hydrochloric acid. In the same manner, 310.3 parts of solid treated pigment particles 8 was obtained.

(Example 9) Production of treated pigment particles 9 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) in the first step were added to the styrene-acrylic acid copolymer. (manufactured by BASF Japan, Joncryl HPD 296, nonvolatile content 35.5%) was changed to 42.3 parts, and 1862 parts of distilled water in the second step was changed to 1864 parts of distilled water in the same manner as in Example 7. 307.1 parts of solid treated pigment particles 9 were obtained. At this time, the pH of the pigment suspension in the first step was 8.3.

(Example 10) Production of treated pigment particles 10 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan Co., Ltd., Joncryl HPD 96, non-volatile content 34%) in the first step were added to the styrene-acrylic acid copolymer. (manufactured by BASF Japan, Joncryl HPD 396, nonvolatile content 31.7%) was changed to 47.3 parts, and 1862 parts of distilled water in the second step was changed to 1859 parts of distilled water in the same manner as in Example 7. to obtain 10 308.7 parts of solid treated pigment particles. At this time, the pH of the pigment suspension in the first step was 8.2.

(Example 11) Production of treated pigment particles 11 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan Co., Ltd., Joncryl HPD 96, non-volatile content 34%) in the first step were added to the styrene-acrylic acid copolymer. (BASF Japan Co., Ltd., Joncryl 678, non-volatile content 98.7%) 15.2 parts, the same procedure as in Example 7 except that 1862 parts of distilled water in the second step was changed to 1892 parts of distilled water. , to obtain 310.3 parts of solid treated pigment particles 11. At this time, the pH of the pigment suspension in the first step was 8.

(Example 12) Production of treated pigment particles 12 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan Co., Ltd., Joncryl HPD 96, non-volatile content 34%) in the first step were added to the styrene-acrylic acid copolymer. (BASF Japan Co., Ltd., Joncryl HPD 96, nonvolatile content 34%) changed to 132.4 parts, distilled water 1862 parts in the second step, 80% acetic acid 93.8 parts, distilled water 1586 parts, 80% acetic acid 281 336.4 parts of solid treated pigment particles 12 were obtained in the same manner as in Example 7 except that the content was changed to 3 parts. At this time, the pH of the pigment suspension in the first step was 8.2.

(Example 13) Production of Treated Pigment Particles 13 As a first step, C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, styrene-acrylic acid copolymer as a dispersion aid (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34%) 44.1 parts, as a liquid medium 2000 parts of distilled water was added to prepare a mixed solution with a pH of 8. This mixed solution is treated with a rotor-stator processor (manufactured by Silverson Nippon Co., Ltd., device name: L5M-A, square hole high shear screen, batch type, distance between the blade part and the wall part of the stator: 0.24 mm). , shear rate 62000 s ⁻¹ (rotational speed 7500 rpm, peripheral speed 14.9 m/s), pulverization treatment of the mixed solution was performed for 1 hour at 40° C. to prepare a pigment suspension of pH=8.

As a second step, an acidic aqueous solution at 25° C. consisting of 1862 parts of distilled water and 93.8 parts of 80% acetic acid was separately prepared. The pigment suspension obtained in the first step is dropped into this acidic aqueous solution over 30 minutes to precipitate the pigment suspension, which is then filtered and washed with water to obtain a treated pigment coated with a dispersing aid. A wet cake of particles 13 was obtained. The wet cake was dried at 80° C. for 24 hours and pulverized to obtain 308.7 parts of solid treated pigment particles 13.

(Example 14) Production of treated pigment particles 14 As the first step, C.I. I. Pigment Blue
15: 3 wet cake (Synthesis Example 1, copper phthalocyanine pigment P-1, nonvolatile content 40%) 500 parts, styrene-acrylic acid copolymer as a dispersion aid (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34 %) and 2557 parts of distilled water as a liquid medium were added to prepare a mixed solution of pH=8. A rotor-stator processing machine (manufactured by Silverson Nippon Co., Ltd., equipment name: VERSO, square hole high shear screen, in-line type, distance between the blade part and the wall part of the stator: 0.24 mm) connected by piping from the bottom discharge valve. Using a shear rate of 62000 s ^-1 (rotation speed 7500 rpm, peripheral speed 14.9 m / s), the mixed liquid was subjected to circulation pulverization treatment at 40 ° C. for 1 hour to prepare a pigment suspension of pH = 8. .

In the second step, 62.5 parts of 80% acetic acid was added dropwise over 30 minutes to the obtained pigment suspension while circulating it with a Silverson processor to precipitate the pigment suspension. , filtration and washing with water to obtain a wet cake of treated pigment particles 14 coated with a dispersing aid. The non-volatile content of this wet cake was 40%. The wet cake was dried at 80° C. for 24 hours and pulverized to obtain 206.9 parts of solid treated pigment particles 14.

(Example 15) Production of Treated Pigment Particles 15 The procedure of Example 14 was repeated except that 25% aqueous ammonia was added so that the pH of the pigment suspension in the first step was adjusted to 10. Solid treated pigment particles 15 were obtained. 8 copies were obtained.

(Example 16) Production of Treated Pigment Particles 16 Except for changing the shear rate during the circulation pulverization treatment in the first step from 62000 s ^-1 to 83000 s ^-1 (rotation speed 10000 rpm, peripheral speed 19.9 m/s) Example 14 was repeated to obtain 205.8 parts of solid treated pigment particles 16.

(Example 17) Production of treated pigment particles 17 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) in the first step were added to the styrene-maleic acid copolymer. (BYKJET 9151, non-volatile content 100%, manufactured by BYK-Chemie) was changed to 10.0 parts, 80% acetic acid was added to make a mixed solution of pH = 6, and 62.5 parts of 80% acetic acid in the second step. was carried out in the same manner as in Example 14 except that 166.7 parts of 30% sodium hydroxide was used to obtain 206.9 parts of solid treated pigment particles 17. At this time, the pH of the pigment suspension in the first step was 6.

(Example 18) Production of treated pigment particles 18 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) in the first step was added to an acrylic urethane resin (Synthesis Example 2 , acrylic urethane resin emulsion 1, non-volatile content 34%) were changed to 29.4 parts in the same manner as in Example 14 to obtain 204.8 parts of solid treated pigment particles 18. At this time, the pH of the pigment suspension in the first step was 7.1.

(Example 19) Production of treated pigment particles 19 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) in the first step were added to laurylamine of copper phthalocyanine sulfonic acid. The procedure of Example 14 was repeated except that the salt (Synthesis Example 3, phthalocyanine compound 1) was changed to 10.0 parts to obtain 205.8 parts of solid treated pigment particles 19. At this time, the pH of the pigment suspension in the first step was 7.3.

(Example 20) Production of treated pigment particles 20 44.1 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) in the first step were added to {N-[3-( Diethylamino)propyl]sulfamoyl}copper phthalocyanine (Synthesis Example 4, phthalocyanine compound 2) was used in the same manner as in Example 14, except that 10.0 parts of solid processed pigment particles 20 were obtained. At this time, the pH of the pigment suspension in the first step was 8.4.

(Example 21) Production of Treated Pigment Particles 21 The procedure of Example 14 was repeated except that 2557 parts of distilled water in the first step was changed to 1129 parts of distilled water and 1429 parts of methanol. got the part

(Example 22) Production of Treated Pigment Particles 22 The first step was carried out in the same manner as in Example 14.
As a second step, the resulting pigment suspension was subjected to a rotary evaporator to remove distilled water under reduced pressure until the pigment suspension solidified. The resulting solid was dried at 80° C. for 24 hours and pulverized to obtain 205.8 parts of solid treated pigment particles 22.

(Comparative Example 1) Production of Treated Pigment Particles 23 As a first step, C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 200 parts, styrene-acrylic acid copolymer as a dispersion aid (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34%) 29.4 parts, as a liquid medium 2857 parts of distilled water was added to prepare a mixed solution of pH=8. This mixed solution is disintegrated using a dissolver (manufactured by Eiko Seiki Co., Ltd., device name: DISPERMAT LC75, disk diameter: 50 mm) at a rotation speed of 3000 rpm and 40 ° C. for 1 hour, pH = 8. of pigment suspension was prepared.

In the second step, while stirring with a dissolver, 62.5 parts of 80% acetic acid is added dropwise to the obtained pigment suspension over 30 minutes to precipitate the pigment suspension, which is then filtered and washed with water. A wet cake of treated pigment particles 23 coated with a dispersing aid was obtained. This wet cake is dried at 80° C. for 24 hours and pulverized to obtain solid treated pigment particles 23 .
205.8 parts were obtained.

(Comparative Example 2) Production of Treated Pigment Particles 24 As a first step, C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 10 parts, styrene-acrylic acid copolymer as a dispersion aid (manufactured by BASF Japan, Joncryl HPD 96, nonvolatile content 34%) 1.5 parts, as a liquid medium 143 parts of distilled water and 100 parts of 1.5 mm glass beads were added to prepare a mixed solution of pH=8. This mixture was crushed for 4 hours using a paint conditioner (manufactured by Red Devil) to prepare a pigment suspension of pH=8.

In the second step, 3.1 parts of 80% acetic acid is dropped into the resulting pigment suspension over 30 minutes to precipitate the pigment suspension. A wet cake of treated pigment particles 24 coated with was obtained. The wet cake was dried at 80° C. for 24 hours and pulverized to obtain 10.3 parts of solid treated pigment particles 24.

Comparative Example 3 Production of Treated Pigment Particles 25 The solid treated pigment particles 25 204 were produced in the same manner as in Example 1 except that 30% sodium hydroxide was added so that the pH of the pigment suspension in the first step was 12. .8 parts were obtained.

(Comparative Example 4) Production of Treated Pigment Particles 26 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 200 parts, distilled water 2857 parts, C.I. I. Pigment Blue 15:3 wet cake (Synthesis Example 1, copper phthalocyanine pigment P-1, non-volatile content 40%) was changed to 500 parts and distilled water was changed to 2557 parts. 206.9 parts were obtained. At this time, the pH of the pigment suspension in the first step was 8.

(Comparative Example 5) Production of Treated Pigment Particles 27 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 10 parts, distilled water 143 parts, C.I. I. Pigment Blue 15:3 wet cake (Synthesis Example 1, copper phthalocyanine pigment P-1, non-volatile content 40%) was changed to 25 parts and distilled water was changed to 128 parts. 10.2 parts were obtained. At this time, the pH of the pigment suspension in the first step was 8.

(Comparative Example 6) Production of Treated Pigment Particles 28 The solid treated pigment particles 28 were prepared in the same manner as in Example 14 except that 30% sodium hydroxide was added so that the pH of the pigment suspension in the first step was 12. .8 parts were obtained.

(Example 101) Production of Treated Pigment Particles 101 29.4 parts of the styrene-acrylic acid copolymer (manufactured by BASF Japan, Joncryl HPD 96, non-volatile content 34%) in the first step was added to the methacrylic acid block polymer (Synthesis Example Resin solution 1 of 6 (non-volatile content 25%) was changed to 60 parts, and distilled water in the second step was changed from 1862 parts to 1846 parts. Obtained. At this time, the pH of the mixed solution in the first step was 8.3.

(Example 102) Production of Treated Pigment Particles 102 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile content 25%) in the first step was 25%) was changed to 60 parts, the same procedure as in Example 101 was repeated to obtain 309.3 parts of Solid Treated Pigment Particles 102. At this time, the pH of the mixed solution in the first step was 8.1.

(Example 103) Production of Treated Pigment Particles 103 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile %) was changed to 60 parts, the same procedure as in Example 101 was repeated to obtain 310.0 parts of Solid Treated Pigment Particles 103. At this time, the pH of the mixed solution in the first step was 8.4.

(Example 104) Production of Treated Pigment Particles 104 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile content 25%) in the first step was 25%) was changed to 60 parts, the same procedure as in Example 101 was repeated to obtain 308.7 parts of Solid Treated Pigment Particles 104. At this time, the pH of the mixed solution in the first step was 8.1.

(Example 105) Production of Treated Pigment Particles 105 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile content 25%) in the first step was copolymerized with α-olefin-maleic anhydride-maleic acid monoisopropyl ester. Same as Example 101, except that 15 parts of the coalescence (NUCERA Ceramer 1608, acid value 160 mgKOH/g, non-volatile matter 100%) was dissolved in dimethylaminoethanol equivalent to the acid value equivalent and hot water to prepare 60 parts. In the same manner, 309.0 parts of solid processed pigment particles 105 was obtained. At this time, the pH of the mixed solution in the first step was 8.2.

(Example 106) Production of Treated Pigment Particles 106 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile content 25%) in the first step was mixed with styrene-maleic acid copolymer ammonium salt (SMA3000H manufactured by Cray Valley; Acid value: 265-305 mgKOH/g, non-volatile content: 15%) was changed to 100 parts, and distilled water in the second step was changed from 1,846 parts to 1,806 parts. 8 copies were obtained. At this time, the pH of the mixed solution in the first step was 8.4.

(Example 107) Production of Treated Pigment Particles 107 60 parts of the methacrylic acid block polymer in the first step (resin solution 1 of Synthesis Example 6, non-volatile content 25%) was mixed with a maleated rosin resin (Malquedo No. 32, manufactured by Arakawa Chemical Co., Ltd., acid value 120 to 140 mg KOH / g, non-volatile content 100%) 15 parts dissolved in acid value equivalent potassium hydroxide and hot water to prepare 150 parts, distilled water 1846 parts in the second step to 1756 parts 309.6 parts of solid processed pigment particles 107 were obtained in the same manner as in Example 101 except for the changes. At this time, the pH of the mixed solution in the first step was 10.8.

(Example 108) Production of Treated Pigment Particles 108 60 parts of the methacrylic acid block polymer in the first step (resin solution 1 of Synthesis Example 6, non-volatile content 25%) was added to a polymerized rosin resin (Aradigm R-95 manufactured by Arakawa Chemical Co., Ltd., acid value 158 to 168 mg KOH / g, non-volatile content 100%) 15 parts was dissolved in acid value equivalent potassium hydroxide and hot water to prepare 150 parts, and 1846 parts of distilled water in the second step was changed to 1756 parts. 308.1 parts of solid treated pigment particles 108 were obtained in the same manner as in Example 101 except that At this time, the pH of the mixed solution in the first step was 10.6.

(Example 109) Production of Treated Pigment Particles 109 60 parts of the methacrylic acid block polymer in the first step (resin solution 1 of Synthesis Example 6, non-volatile content 25%) was added to disproportionated rosin (Londis K-25 manufactured by Arakawa Chemical Co., Ltd., non-volatile 310.0 parts of Solid Treated Pigment Particles 109 were obtained in the same manner as in Example 101, except that the content was changed to 60 parts (25%). At this time, the pH of the mixed solution in the first step was 10.5.

(Example 110) Production of treated pigment particles 110 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile content 25%) in the first step, 15 parts of carboxy polyester resin (CRYLCOAT 1540-0 manufactured by allnex) The first step was carried out in the same manner as in Example 101, except that the solution dissolved in 45 parts of acetone was changed from 2000 parts of distilled water to 1400 parts of distilled water and 600 parts of acetone. The second step was carried out in the same manner as in Example 22 to obtain 309.6 parts of solid treated pigment particles 110. At this time, the pH of the mixed solution in the first step was 6.9.

(Example 111) Production of treated pigment particles 111 60 parts of the methacrylic acid block polymer in the first step (resin solution 1 of Synthesis Example 6, non-volatile content 25%) was mixed with modified polyacrylate (Dispex Ultra PA 4560 manufactured by BASF, non-volatile content 40%). %) 37.5 parts, 1846 parts of distilled water in the second step was changed to 1888 parts of distilled water, and 93.8 parts of 80% acetic acid was changed to 75 parts of dimethylaminoethanol. 307.8 parts of solid treated pigment particles 111 were obtained. Also, the pH of the mixture in the first step was adjusted to 5.5 using 80% acetic acid.

(Example 112) Production of Treated Pigment Particles 112 60 parts of the methacrylic acid block polymer in the first step (resin solution 1 of Synthesis Example 6, non-volatile content 25%) was mixed with an acrylic block copolymer (Dispex Ultra PA 4575 manufactured by BASF, non-volatile 308.7 parts of solid treated pigment particles 112 were obtained in the same manner as in Example 111, except that the content was changed to 37.5 parts by weight (40%). Also, the pH of the mixture in the first step was adjusted to 5.0 using 80% acetic acid.

(Example 113) Production of treated pigment particles 113 60 parts of the methacrylic acid block polymer (resin solution 1 of Synthesis Example 6, non-volatile content 25%) in the first step was mixed with a block copolymer (DISPERBYK-184 manufactured by BYK Chemie Japan, non-volatile 52%) 28.8 parts, 1888 parts of distilled water in the second step was changed to 1671 parts, and 75 parts of dimethylaminoethanol was changed to 300 parts of 25% ammonia water in the same manner as in Example 111, 307.8 parts of solid treated pigment particles 113 were obtained. Also, the pH of the mixture in the first step was adjusted to 4.5 using 80% acetic acid.

(Example 114) Production of Treated Pigment Particles 114 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Yellow 14 (SYMULER FAST YELLOW 4400 manufactured by DIC) was used in the same manner as in Example 7, except that 300 parts of solid processed pigment particles 114 were obtained. At this time, the pH of the mixed solution in the first step was 8.1.

Example 115 Preparation of Treated Pigment Particles 115 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Yellow 74 (Fast Yellow 7413 manufactured by Sanyo Color Co., Ltd.) was used in the same manner as in Example 7 except that 300 parts was used to obtain 308.1 parts of solid processed pigment particles 115. At this time, the pH of the mixed solution in the first step was 8.0.

(Example 116) Preparation of Treated Pigment Particles 116 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Yellow 180 (Ink Jet Yellow HG 01 VP 6252 manufactured by Clariant) was used in the same manner as in Example 7 except that 300 parts was used to obtain 308.4 parts of solid processed pigment particles 116. At this time, the pH of the mixed solution in the first step was 8.2.

(Example 117) Preparation of Treated Pigment Particles 117 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Yellow 185 (Paliotol Yellow D1155 manufactured by DIC) was changed to 300 parts in the same manner as in Example 7 to obtain 308.7 parts of solid processed pigment particles 117. At this time, the pH of the mixed solution in the first step was 8.3.

Example 118 Preparation of Treated Pigment Particles 118 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Red 150 (Toshiki Red 150TR manufactured by Tokyo Shikizai Co., Ltd.) was used in the same manner as in Example 7, except that 308.4 parts of solid processed pigment particles 118 were obtained. At this time, the pH of the mixed solution in the first step was 8.3.

(Example 119) Preparation of Treated Pigment Particles 119 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Red 269 (SYMULER FAST RED 1022 manufactured by DIC) was changed to 300 parts in the same manner as in Example 7 to obtain 309.3 parts of solid processed pigment particles 119. At this time, the pH of the mixed solution in the first step was 8.2.

(Example 120) Production of Treated Pigment Particles 120 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Red 254 (Cinilex DPP Red ST manufactured by CINIC) was used in the same manner as in Example 7 except that 300 parts was used to obtain 308.7 parts of solid processed pigment particles 120. At this time, the pH of the mixed solution in the first step was 8.0.

(Example 121) Production of Treated Pigment Particles 121 By carrying out the first step in the same manner as in Example 120 and the second step in the same manner as in Example 22, 308.4 parts of solid treated pigment particles 121 were obtained.

(Example 122) Preparation of Treated Pigment Particles 122 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Blue 15:1 (LIONOL BLUE 7186-PM manufactured by Toyocolor Co., Ltd.) was changed to 300 parts in the same manner as in Example 7 to obtain 308.7 parts of solid processed pigment particles 122. At this time, the pH of the mixed solution in the first step was 8.1.

(Example 123) Production of Treated Pigment Particles 123 By carrying out the first step in the same manner as in Example 122 and the second step in the same manner as in Example 22, 308.4 parts of solid treated pigment particles 123 were obtained.

Example 124 Preparation of Treated Pigment Particles 124 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Violet 19 (Inkjet Magenta E5B02 manufactured by Clariant) was used in the same manner as in Example 7 except that 300 parts was used to obtain 308.4 parts of solid processed pigment particles 124. At this time, the pH of the mixed solution in the first step was 8.0.

Example 125 Preparation of Treated Pigment Particles 125 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Green 7 (Heliogen Green D 8730 manufactured by BASF) was used in the same manner as in Example 7, except that 300 parts of solid processed pigment particles 125 were obtained. At this time, the pH of the mixed solution in the first step was 8.2.

(Example 126) Production of Treated Pigment Particles 126 By carrying out the first step in the same manner as in Example 125 and the second step in the same manner as in Example 22, 308.7 parts of solid treated pigment particles 126 were obtained.

Example 127 Preparation of Treated Pigment Particles 127 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Violet 23 (LIONOGEN VIOLET FG-6140 manufactured by Toyocolor Co., Ltd.) was changed to 300 parts in the same manner as in Example 7 to obtain 308.7 parts of solid treated pigment particles 127. At this time, the pH of the mixed solution in the first step was 8.3.

(Example 128) Production of Treated Pigment Particles 128 By carrying out the first step in the same manner as in Example 127 and the second step in the same manner as in Example 22, 310.0 parts of solid treated pigment particles 128 were obtained.

Example 129 Preparation of Treated Pigment Particles 129 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) 300 parts, C.I. I. Pigment Orange 73 wet cake (Synthesis Example 5 non-volatile content 35%) was changed to 857 parts, and 2000 parts of distilled water was changed to 1443 parts. got At this time, the pH of the mixed solution in the first step was 7.9.

(Example 130) Production of Treated Pigment Particles 130 The procedure of Example 129 was repeated except that 1,862 parts of distilled water in the second step was changed to 1,918 parts, and 93.8 parts of 80% acetic acid was changed to 37.5 parts of phosphoric acid. 207.3 parts of solid treated pigment particles 130 were obtained.

(Comparative Example 101) Production of Treated Pigment Particles 201 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Yellow 14 (SYMULER FAST YELLOW 4400 manufactured by DIC) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 206.2 parts of solid processed pigment particles 201.

(Comparative Example 102) Production of Treated Pigment Particles 202 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Yellow 74 (Fast Yellow 7413 manufactured by Sanyo Color Co., Ltd.) was used in the same manner as in Comparative Example 1 except that 200 parts was used to obtain 204.8 parts of Solid Processed Pigment Particles 202.

(Comparative Example 103) Production of Treated Pigment Particles 203 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Yellow 180 (Ink Jet Yellow HG 01 VP 6252 manufactured by Clariant) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 206.9 parts of solid processed pigment particles 203.

(Comparative Example 104) Production of Treated Pigment Particles 204 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Yellow 185 (Paliotol Yellow D1155 manufactured by DIC) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 206.9 parts of solid processed pigment particles 204.

(Comparative Example 105) Production of Treated Pigment Particles 205 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Red 150 (Toshiki Red 150TR manufactured by Tokyo Shikizai Co., Ltd.) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 205.6 parts of solid processed pigment particles 205.

(Comparative Example 106) Production of Treated Pigment Particles 206 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Red 269 (SYMULER FAST RED 1022 manufactured by DIC) was used in the same manner as in Comparative Example 1 except that 200 parts was used to obtain 204.8 parts of solid processed pigment particles 206.

(Comparative Example 107) Production of Treated Pigment Particles 207 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Red 254 (Cinilex DPP Red ST manufactured by CINIC) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 205.2 parts of solid treated pigment particles 207.

(Comparative Example 108) Production of Treated Pigment Particles 208 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Blue 15:1 (LIONOL BLUE 7186-PM manufactured by Toyocolor Co., Ltd.) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 208 204.8 parts of solid processed pigment particles.

(Comparative Example 109) Production of Treated Pigment Particles 209 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Violet 19 (Inkjet Magenta E5B02 manufactured by Clariant) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 206.2 parts of solid processed pigment particles 209.

(Comparative Example 110) Production of Treated Pigment Particles 210 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Green 7 (Heliogen Green D 8730 manufactured by BASF) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 206.0 parts of solid processed pigment particles 210.

(Comparative Example 111) Production of Treated Pigment Particles 211 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Violet 23 (LIONOGEN VIOLET FG-6140 manufactured by Toyocolor Co., Ltd.) was changed to 200 parts in the same manner as in Comparative Example 1 to obtain 205.0 parts of solid treated pigment particles 211.

(Comparative Example 112) Production of Treated Pigment Particles 212 C.I. I. Pigment Red 122 (manufactured by Clariant Japan, Toner Magenta E) was added to 200 parts of C.I. I. Pigment Orange 73 wet cake (Synthesis Example 5, non-volatile content 35%) was changed to 571 parts, and distilled water was changed from 2,857 parts to 2,486 parts. Got 2 copies.

<Pigment dispersion>
Pigment dispersions were prepared using the resulting treated pigment particles and their properties were evaluated.

1. Production of Polymerizable Monomer Pigment Dispersion (Examples a-1 to a-22, a-101 to a-130, Comparative Examples a-1 to a-8, a-101 to a-112) Pigment Dispersion a -1 to a-30, a-101 to a-130, a-201 to a-212 Preparation of 15.75 parts of solid processed pigment particles 1 as a pigment, Solsperse 32000 (pigment dispersion manufactured by Lubrizol Co., Ltd.) as a dispersion medium 7.5 parts of resin) and 76.75 parts of isobornyl acrylate (Miwon's polymerizable monomer, Miramer M1140) were sequentially charged into a tank and stirred with a high-speed mixer until uniform. A pigment dispersion a-1 was prepared by dispersing for 1 hour using a Dyno mill with a volume of 0.6 L filled with 1800 g of zirconia beads.

With the composition shown in Table 1, the same operation as for the pigment dispersion a-1 was performed to obtain pigment dispersions a-2 to a-30, a-101 to a-130, and a-201 to a-212. made.

2. Preparation of aqueous pigment dispersion (Examples b-1 to b-23, b-101 to b-130, Comparative Examples b-1 to b-8, b-101 to a-112) Pigment dispersion b-1 to Preparation of b-31, b-101 to b-130, b-201 to b-212 21.0 parts of solid processed pigment particles 1 as a pigment, BYKJET-9151 (pigment dispersion resin manufactured by BYK-Chemie) as a dispersion medium 8 0 part, 1.0 part of Surfynol 104E (antifoaming agent manufactured by Evonik), and 70.0 parts of ion-exchanged water are sequentially charged into a tank, pre-dispersed with a stirrer, and then 1800 g of zirconia beads having a diameter of 0.5 mm. Pigment dispersion b-1 was prepared by carrying out main dispersion for 2 hours using a 0.6 L volume Dyno mill filled with .

With the composition shown in Table 2, the same operation as for the pigment dispersion b-1 was performed to obtain pigment dispersions b-2 to b-31, b-101 to b-130, and b-201 to b-212. made.

3. Evaluation of pigment dispersion (dispersibility (particle size))
For the pigment dispersion prepared above, Nanotrac manufactured by Microtrack Bell
Using WaveII, the volume-based cumulative 50% particle size ( _D50 ) and cumulative 90% particle size ( _D90 ) were measured. When measuring the polymerizable monomer-based pigment dispersion, isobornyl acrylate was used to dilute the polymerizable monomer pigment dispersion to a measurable concentration, and the measurement was carried out. On the other hand, when measuring the water-based pigment dispersion, the measurement was performed after appropriately diluting with ion-exchanged water so as to obtain a measurable concentration. Evaluation results are shown in Tables 1 and 2.

(dispersion stability)
The pigment dispersion was filled into a sealable storage bottle at 90% fill capacity and left at 60° C. for 2 weeks. The rate of change in viscosity before and after standing was evaluated based on the following evaluation criteria to evaluate storage stability. The evaluation criteria are as follows, and the smaller the rate of change, the better the stability, and evaluations of 4 to 2 are considered practical. Evaluation results are shown in Tables 1 and 2.
4: The rate of change is less than 5% from the initial stage.
3: The rate of change is 5% or more and less than 10% from the initial stage.
2: The rate of change is 10% or more and less than 20% with respect to the initial stage.
1: The rate of change is 20% or more from the initial stage.

Details of the raw materials shown in Tables 1 and 2 are as follows.
- Toner Magenta E: C.I. I. Pigments
Red 122
Dried and pulverized product of Synthesis Example 1: A powdery C obtained by drying and pulverizing the wet cake containing the copper phthalocyanine pigment [P-1] of Synthesis Example 1 at 80 ° C. for 24 hours. . I. Pigment Blue 15:3

From the results in Tables 1 and 2, the treated pigment particles obtained by the pigment treatment method of the present invention are excellent in dispersibility, have a fine and uniform dispersed particle size, and obtain a pigment dispersion excellent in dispersion stability. be able to.

<Ink>
An inkjet ink was prepared using the obtained pigment dispersion and its properties were evaluated.

1. Preparation of active energy ray-curable inkjet ink (Examples A-1 to A-22, A-101 to A-130, Comparative Examples A-1 to A-8, A-101 to A-112) Active energy ray curing Preparation of type inkjet inks A-1 to A-30, A-101 to A-130, A-201 to A-212 In the mixing container, the following pigment dispersion, polymerizable monomer, photopolymerization initiator, polymerization inhibitor The agent and the surface control agent were sequentially charged while stirring, and mixed at 40 to 50° C. until the photopolymerization initiator, which was a solid component, was dissolved.
Pigment dispersion a-1: 26.7 parts Isobornyl acrylate (Miwon polymerizable monomer, Miramer M1140): 11.3 parts Cyclic trimethylolpropane formal acrylate (Miwon polymerizable monomer, Miramer M1110 ): 32 parts 1,6-hexanediol diacrylate (Miwon polymerizable monomer, Miramer M200): 19.2 parts 2,4,6-trimethylbenzoyldiphenylphosphine oxide (IGM Resins photopolymerization initiator , Omnirad TPO H): 5 parts Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (photopolymerization initiator manufactured by IGM Resins, Omnirad 819): 3 parts 2,4-diethylthioxanthone (manufactured by Lambson Photopolymerization initiator, SpeedCure DETX): 2 parts 2,6-di-tert-butyl-4-methylphenol (polymerization inhibitor manufactured by Seiko Chemical Co., Ltd., BHT Swanox): 0.4 parts Siloxane-based surface tension modifier (BYK348 manufactured by BYK-Chemie): 0.4 parts Then, filtration was performed using a depth-type filter with a pore size of 1 μm to remove coarse particles, thereby preparing an active energy ray-curable inkjet ink A-1.

Except for changing the pigment dispersion as shown in Table 3, the same operation as for the active energy ray-curable inkjet ink A-1 was performed, and active energy ray-curable inkjet inks A-2 to A-30 and A101 to A-130, A-201 to A-212 were produced.

2. Evaluation of active energy ray-curable inkjet ink (production of solid printed matter)
The active energy ray-curable inkjet ink prepared above using an inkjet ejection device (OnePassJET) equipped with a Kyocera head (resolution 600 dpi × 600 dpi) and a metal halide lamp described later above a conveyor that can transport a recording medium. was printed on a PET substrate (PET25(A) PLshin 8LK) manufactured by Lintec under the conditions of a droplet volume of 14 pL and a printing rate of 100%. Then, using a 240 W/cm metal halide lamp manufactured by GEW, the printed matter was irradiated so that the integrated amount of light was 200 mJ/cm 2 , and the ink was cured to prepare a solid printed matter. A series of steps from printing to curing were performed at a printing speed of 50 m/min.

(optical density)
The optical density (OD value) of the solid print obtained by the above method was measured using a spectrodensitometer (eXact manufactured by X-RITE). The light source was C, the viewing angle was 2°, the density status was Status G, and the density white reference was an absolute value. The evaluation criteria are as follows. The higher the OD value, the better the optical density. Table 3 shows the evaluation results.
4: OD value is 1.25 or more 3: OD value is 1.15 or more and less than 1.25 2: OD value is 1.05 or more and less than 1.15 1: OD value is less than 1.05

(transparency)
A piece of black paper, the black density of which had been measured in advance, was placed so as to overlap the surface opposite to the printed surface of the solid print. Then, using a reflection spectrophotometer (X-Rite 939 manufactured by X-Rite), the black density was measured from the printed surface side, and the transparency was calculated based on Equation 1 below. The evaluation criteria are as follows. The higher the calculated value, the better the transparency, and evaluations of 4 to 2 are considered practical. Table 3 shows the evaluation results.
4: Transparency of 95% or more 3: Transparency of 90% or more and less than 95% 2: Transparency of 85% or more and less than 90% 1: Transparency of less than 85%

Formula 1: Transparency (%) = black density through printing surface / black density of black paper x 100

(dispersion stability)
The ink was filled into a sealable storage bottle at 90% fill and left at 60° C. for 2 weeks. The rate of change in viscosity before and after standing was evaluated based on the following evaluation criteria to evaluate storage stability. The evaluation criteria are as follows, and the smaller the rate of change, the better the stability, and evaluations of 4 to 2 are considered practical. Table 3 shows the evaluation results.
4: The rate of change is less than 5% from the initial stage.
3: The rate of change is 5% or more and less than 10% from the initial stage.
2: The rate of change is 10% or more and less than 20% with respect to the initial stage.
1: The rate of change is 20% or more from the initial stage.

(Angle dependence of hue)
The printed material was observed while changing the angle of the light source striking the printing surface of the solid printed material, and the change in hue was evaluated. The evaluation criteria are as follows, and the smaller the change, the smaller the angle dependence of the hue, which is good. An evaluation of 4 to 3 is judged to be practical. Table 3 shows the evaluation results.
4: Substantially no reflected light complementary to the printed matter is observed.
3: A little reflected light of complementary color is observed with respect to the printed matter.
2: Reflected light of complementary color is strongly observed with respect to the printed matter.
1: Very strong reflected light complementary to the printed matter is observed.

3. Preparation of water-based inkjet inks (Examples B-1 to B-23, B-101 to B-130, Comparative Examples B-1 to B-8, B-101 to B-112) Water-based inkjet inks B-1 to B Preparation of B-31, B-101 to B-130, B-201 to B-212 In the mixing container, the following pigment dispersion, ion-exchanged water, resin emulsion aqueous solution, moisturizing solvent, surface conditioner, pH adjuster, The preservatives were sequentially added while stirring, and mixed with stirring at room temperature for about 15 minutes.
Pigment dispersion: 20.0 parts Ion-exchanged water: 36.5 parts Resin emulsion aqueous solution JE-1056 Seiko PMC (meth) acrylic resin emulsion (water-insoluble resin, non-volatile content 42.5%): 9.5 parts Moisturizing solvent propylene glycol: 30.0 parts Surface conditioner BYK-348 BYK-Chemie polyoxyethylene-modified polydimethylsiloxane: 3.0 parts pH adjuster triethanolamine: 1.0 parts Filtration was performed using a depth-type filter with a pore size of 1 μm to remove coarse particles, thereby producing an active energy ray-curable inkjet ink B-1.

Aqueous inkjet inks B-2 to B-31, B-101 to B-130, B- 201 to B-212 were produced.

4. Evaluation of water-based inkjet ink (preparation of printed matter for optical density evaluation)
Using an inkjet ejection device (OnePassJET) equipped with a Kyocera head (resolution 600 dpi × 600 dpi) above a conveyor that can convey the recording medium, the water-based inkjet ink prepared above was applied with a droplet volume of 14 pL and a printing rate. Under the condition of 100%, it was discharged and printed on OK Topcoat+ (basis weight: 104.7 g/m ² ), which is a coated paper manufactured by Oji Paper Co., Ltd. Immediately after printing, the film was dried in an air oven at 60° C. for 3 minutes, and then evaluated for optical density.

(Optical Density Evaluation Method)
The optical density (OD value) was measured using a spectrodensitometer (eXact manufactured by X-RITE) for the solid print using OK Topcoat+ obtained by the above method. The light source was C, the viewing angle was 2°, the density status was Status G, and the density white reference was an absolute value. The evaluation criteria are as follows. The higher the OD value, the better the optical density. Table 4 shows the evaluation results.
4: OD value is 1.25 or more 3: OD value is 1.15 or more and less than 1.25 2: OD value is 1.05 or more and less than 1.15 1: OD value is less than 1.05

(Preparation of coated material for transparency evaluation)
Using a K control coater manufactured by Matsuo Sangyo Co., Ltd. and a K hand coater with a wire diameter of 6 mil (coating film thickness 12 μm), byco-chart, a concealment test paper manufactured by BYK Chemie, is coated with the water-based inkjet ink created above. After drying for 3 minutes using a 60° C. air oven, the transparency was evaluated.

(Transparency evaluation method)
Using the coated material obtained by the above method, the black density of the ink coating film coated on the black part of the coating substrate is measured using a reflection spectrophotometer (X-Rite 939 manufactured by X-Rite). Then, the transparency was calculated based on the following formula 1. The evaluation criteria are as follows. The higher the calculated value, the better the transparency, and evaluations of 4 to 2 are considered practical. Table 4 shows the evaluation results.
4: Transparency of 95% or more 3: Transparency of 90% or more and less than 95% 2: Transparency of 85% or more and less than 90% 1: Transparency of less than 85%

Formula 1:
Transparency (%) = black density of ink film applied to black portion of coating substrate/black density of black portion of coating substrate x 100

(dispersion stability)
The ink was filled into a sealable storage bottle and left at 60° C. for 2 weeks. The rate of change in viscosity before and after standing was evaluated based on the following evaluation criteria to evaluate storage stability. The evaluation criteria are as follows, and the smaller the rate of change, the better the stability, and evaluations of 4 to 2 are considered practical. Table 4 shows the evaluation results.
4: The rate of change is less than 5% from the initial stage.
3: The rate of change is 5% or more and less than 10% from the initial stage.
2: The rate of change is 10% or more and less than 20% with respect to the initial stage.
1: The rate of change is 20% or more from the initial stage.

(Angle dependence of hue)
The printed material was observed while changing the angle of the light source striking the printing surface of the solid printed material, and the change in hue was evaluated. The evaluation criteria are as follows, and the smaller the change, the smaller the angular dependence of the hue and the better. An evaluation of 4 to 3 is judged to be practical. Table 4 shows the evaluation results.
4: Substantially no reflected light complementary to the printed matter is observed.
3: A small amount of reflected light complementary to the printed matter is observed.
2: Reflected light of complementary color is strongly observed with respect to the printed matter.
1: Very strong reflected light complementary to the printed matter is observed.

From the results in Tables 3 and 4, the pigment treatment method of the present invention can obtain pigments with good optical density, transparency and dispersion stability. Further, when the pigment composition is precipitated by an acid precipitation method or a salting-out method, it is possible to obtain a good pigment in which the angle dependency of the hue is suppressed.

P, P': pigment particles 100: supply section 200: discharge section

Claims (4)

A pigment treatment method comprising the following steps.
A first step of preparing a pigment suspension having a pH of 3.0 to 11.0 by pulverizing the pigment, dispersing aid and liquid medium with a rotor-stator processing machine, followed by precipitation treatment of the pigment suspension. A second step of making a wet cake or solid treated pigment particles of treated pigment particles coated with a dispersing aid. 2. The method of claim 1, wherein said rotor-stator processor is an in-line processor to which pigment, dispersing aid and liquid medium are continuously supplied. 3. The method of claim 1 or 2, wherein the second step is precipitation processing of the pigment suspension with an acidic or basic compound to produce a wet cake of treated pigment particles coated with a dispersing aid or solid treated pigment particles. The described pigment treatment method. 3. The pigment treatment method according to claim 1, comprising a third step of dispersing the wet cake or solid treated pigment particles and a dispersion medium to prepare a pigment dispersion.

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