JP5393944B2 - Self-dispersed colored fine particles, aqueous dispersion containing the self-dispersed colored fine particles, and ink for inkjet recording or color filter - Google Patents

Description

  The present invention relates to a color material, a dispersion of color material, and an ink that are inks for inkjet recording and color filters. More specifically, it has a function of dispersing in an aqueous dispersion medium without using a dispersant such as a surfactant or a water-soluble resin, has excellent storage stability during preparation of the aqueous dispersion and ink, and clogs the head during printing. Self-dispersing colored fine particles that have excellent discharge stability and excellent color development, transparency, and glossiness of printed matter, and excellent image fastness such as light resistance, water resistance, and fixability, and the self-dispersion The present invention relates to an aqueous dispersion containing fine colored particles, an ink jet recording ink, and a color filter ink.

  Inkjet recording is small and has a low running cost, but enables high-quality color printing, and has rapidly been used in the office and photographic markets. One of the most important factors in this ink jet recording is ink characteristics. In the past, dyes have been mainly used for this ink in view of ejection stability at the printer head, storage stability of the ink, and color development of the printed matter. However, in fields where preservation is required, such as offices and the photographic market, problems such as fading due to light, moisture in the atmosphere, or gases such as ozone are likely to occur.

  Therefore, in recent years, water-insoluble colorants typified by pigments and oil-soluble dyes have been attracting attention for inkjet recording because they have excellent storage stability such as water resistance and light resistance. Since these water-insoluble colorants do not dissolve in a dispersion medium such as water, an aqueous dispersion in which the water-insoluble colorant is dispersed at a high concentration is first prepared, and additives such as wetting agents and penetrants, An organic compound and water are added to prepare the ink.

  In the water-insoluble colorant, dispersion, or ink prepared from them, a clear image cannot be obtained when the water-insoluble colorant is not finely dispersed. Also, when used for printing on an OHP sheet projected by a backlight or for color filter display, a colorful projection image cannot be obtained unless a water-insoluble colorant is finely dispersed to ensure high transparency. Thus, in order to satisfy the same clarity and transparency as the dye, it is necessary to prevent the incident light from being scattered by the coloring material. This scattering depends on the particle size of the coloring material. The smaller the particle size, the more the scattering is suppressed. When the particle size becomes 1/10 or less of visible light, it becomes almost negligible. That is, when the particle size of the water-insoluble colorant is smaller than 50 nm, sharpness and transparency are exhibited. Further, when the crystallite size of the water-insoluble colorant is finer, a more transparent dispersion or ink can be prepared. Further, when the water-insoluble colorant in the ink is finely dispersed and not stabilized, there is a problem of nozzle clogging in the printer head.

  However, it is very difficult to finely disperse the water-insoluble colorant. Usually, the water-insoluble colorant is dispersed by adding a dispersant to the dispersion medium and using a mechanical force with a pulverizing and dispersing machine such as a bead mill or a roll mill. Dispersions and inks obtained by this method can be dispersed only to the primary particle size of the color material used as a raw material, about 100 nm, and an image having sufficient sharpness and transparency cannot be obtained. Furthermore, if the pulverization is performed vigorously and the primary particles are destroyed and dispersed, the dispersion becomes unstable due to an increase in specific surface area and overdispersion due to a local change in the crystal structure of the pigment surface. It is difficult to hold on. That is, an ultrafine water-insoluble colorant prepared by a method different from pulverization and a prepared one are necessary.

  Furthermore, in the case of inkjet recording, additives such as surfactants, water-soluble organic compounds, pH adjusters, preservatives, and the like, in which water-insoluble color materials are dispersed in consideration of permeability to recording media and color development To make ink. In this state, storage stability on a yearly basis is required. In this case, in the case of dispersion using a conventional surfactant or a water-soluble resin or the like, competitive adsorption between the dispersant and the additive occurs on the surface of the water-insoluble colorant, and sufficient dispersion stability cannot be ensured. Therefore, the preparation of a self-dispersing water-insoluble coloring material that hydrophilizes a part of the water-insoluble coloring material and disperses it in an aqueous dispersion medium without using a dispersing agent such as a surfactant or a water-soluble resin, and highly dispersed by the dispersion. Stabilization is considered an effective means.

First, as a method for obtaining an ultrafine water-insoluble color material, a technique called an acid pasting method in which a water-insoluble color material is dissolved in sulfuric acid and poured into water (Patent Document 1), the water-insoluble color material is present in an alkali. The technology to obtain a fine colorant by dissolving in an aprotic polar organic solvent under the conditions below and neutralizing with acid (Patent Document 2), aprotic polar organic in the presence of an alkali with a water-insoluble colorant and a surfactant A technique for obtaining a fine color material by dissolving it in a solvent and putting it in water (Patent Document 3). Dispersing a water-insoluble color material and a dispersant such as a resin in an aprotic polar organic solvent in the presence of an alkali, After obtaining a fine color material by input, acid precipitation and redispersion to obtain a fine color material at a high concentration (Patent Document 4), dissolving a water-insoluble color material in an amide organic solvent, Knows the technology (Patent Document 5) for obtaining fine color materials It has been.
Next, as a method for obtaining a self-dispersion type water-insoluble colorant having a hydrophilic pigment surface, the water-insoluble colorant is sulfonated in a strong acid, neutralized with a base, and then self-dispersed by pulverization using a pulverizer. For obtaining a water-insoluble colorant (Patent Document 6), a technique for obtaining a self-dispersing water-insoluble colorant by substituting a hydrophilic group on the surface of a water-insoluble colorant via an azonium salt (Patent Document 7), an anionic group There is known a technique (Patent Document 8) in which a dissolved water-insoluble colorant solution is added to a hydrophilic medium in which a water-insoluble colorant derivative having water content is dissolved or dispersed.

Japanese Patent Laid-Open No. 9-221616 JP 11-209641 A JP 2003-26972 A JP 2004-43776 A JP 2004-91560 A JP 2002-285067 A Special table 2003-506554 gazette Japanese Patent Laid-Open No. 2002-179977

  Patent Document 1 describes a dispersion and an ink in which a water-insoluble colorant is dissolved in sulfuric acid and poured into water and then dispersed by adding a dispersant. The dispersion particle size is 100 nm or more. It is hard to say that large and sufficient color development and transparency are exhibited.

  In addition, Patent Document 2 describes a fine colorant that is obtained by dissolving a water-insoluble colorant in an aprotic polar organic solvent in the presence of an alkali and then neutralizing with an acid, but has not yet been dispersed. .

  Patent Document 3 describes a technique in which a water-insoluble colorant and a surfactant are dissolved in an aprotic polar organic solvent in the presence of an alkali, and poured into water to obtain a fine colorant dispersion. Yes. However, dispersion stabilization with only a surfactant causes aggregation at the stage of adding an aqueous solvent for inkjet recording and color filters, and it is difficult to say that excellent characteristics can be exhibited in the above applications.

  In Patent Document 4, a water-insoluble colorant and a dispersing agent such as a resin are dissolved in an aprotic polar organic solvent in the presence of an alkali and put into water to obtain a fine colorant. And a technique for obtaining a fine color material at a high concentration by performing redispersion. However, since the association of water-insoluble colorant particles cannot be prevented in the acid precipitation step, a nanometer-order water-insoluble colorant with a uniform size can be stably obtained even after neutralization with alkali. It is hard to say.

  Patent Document 5 describes a technique for obtaining a fine color material by dissolving a water-insoluble color material in an amide-based organic solvent and throwing it into water. However, since there is no treatment to stabilize the dispersion in the system, if the operation is performed to remove the amide organic solvent to a concentration that can actually be used as a coloring material, significant aggregation occurs and it cannot be used in practice. Absent.

  In Patent Document 6, as a method for obtaining a self-dispersing water-insoluble color material having a water-insoluble color material surface hydrophilized, the water-insoluble color material is sulfonated in a strong acid and neutralized with a base. Describes a technique for obtaining a self-dispersion type dispersion by dispersion treatment using a polymer. However, after hydrophilization by sulfonation, dispersion with a disperser is not possible, so it is impossible to obtain a dispersion with a dispersed particle size of 80 nm or less, and it is difficult to say that color development and transparency are sufficient. It is.

  Patent Document 7 describes a technique for obtaining a self-dispersing pigment dispersion by substituting a hydrophilic group on the surface of a water-insoluble colorant via an azonium salt. However, the reaction is complicated and impurities are easily generated, and it is difficult to say that there is an effect in making the particles finer.

  Patent Document 8 describes a technique of adding a dissolved water-insoluble colorant solution in a hydrophilic medium in which a pigment derivative having an anionic group is dissolved or dispersed. However, this system uses a water-soluble colorant derivative as a synergist or surfactant to stabilize the dispersion, and it is difficult to say that it is a sufficient self-dispersing type.

  An object of the present invention relates to a color material or a dispersion of a color material, which is an ink precursor for ink jet recording and a color filter, and an ink, and to an aqueous dispersion medium without using a dispersant such as a surfactant or a water-soluble resin. Dispersed, excellent storage stability during dispersion and ink preparation, no clogging of head during printing, excellent ejection stability, excellent color development, transparency, fixability of printed matter, water resistance, light resistance, etc. It is a technical problem to provide self-dispersed colored fine particles capable of obtaining an image having excellent image fastness, an aqueous dispersion containing the self-dispersed colored fine particles, and an ink containing the self-dispersed colored fine particles.

  The above technical problem can be achieved by the present invention as follows.

That is, according to the present invention, the material constituting the colored fine particles is a water-insoluble colorant, a colorant having the same structure as that of the water-insoluble colorant, or a colorant having the same basic structure, or having the same basic structure and a substituent. Is a composite color material with a hydrophilic color material in which hydrophilic groups are introduced into different color materials , and the cumulative 50% particle size (D50) of the particle size distribution in the number distribution particle size of the composite color material is 40 nm or less that self a method of manufacturing a dispersion type colored fine particles, hydrophilic colorant preparation step of preparing a hydrophilic colorant,
A dissolution reprecipitation step in which the water-insoluble colorant and the hydrophilic colorant are dissolved in an aprotic polar solvent, and charged into an aqueous dispersion medium to obtain a self-dispersed colored fine particle crude;
Concentration dialysis step of concentrating and dialyzing the resulting self-dispersed colored fine particle crude,
A redispersion step in which a dispersion operation is performed by adding an aqueous dispersion medium, a basic substance or an acidic substance to the obtained paste.
A method for producing self-dispersed colored fine particles, characterized in that the obtained aqueous dispersion is filtered, membrane-separated or centrifuged, and is filtered and dried after a post-treatment step for adjusting the concentration. (Invention 1).

In the present invention, the hydrophilic group of the hydrophilic coloring material is one or more functional groups selected from an anionic group, a cationic group, and a nonionic group. 1 is a method for producing self-dispersed colored fine particles (Invention 2).

Further, the present invention is the method for producing self-dispersed colored fine particles according to the present invention 1 or 2, wherein the hydrophilic colorant is contained in an amount of 2% by weight to 100% by weight based on the water-insoluble colorant ( Invention 3).

Further, the present invention is the method for producing self-dispersed colored fine particles according to any one of the present inventions 1 to 3, wherein the average crystallite size is 25 nm or less (Invention 4).

In the present invention, the material constituting the colored fine particles is a water-insoluble colorant and a colorant having the same structure as that of the water-insoluble colorant, or a colorant having the same basic structure, or having the same basic structure and a substituent. Is a composite color material with a hydrophilic color material in which a hydrophilic group is introduced into a color material having a different structure or a similar structure, and a cumulative particle size distribution of 50% of the particle size distribution in the number distribution particle size of the composite color material (P50) is a method for producing an aqueous dispersion in which self-dispersing colored fine particles are dispersed in an aqueous dispersion medium, wherein the hydrophilic colorant preparation step for preparing a hydrophilic colorant,
A dissolution reprecipitation step in which the water-insoluble colorant and the hydrophilic colorant are dissolved in an aprotic polar solvent, and charged into an aqueous dispersion medium to obtain a self-dispersed colored fine particle crude;
Concentration dialysis step of concentrating and dialyzing the resulting self-dispersed colored fine particle crude,
A redispersion step in which a dispersion operation is performed by adding an aqueous dispersion medium, a basic substance or an acidic substance to the obtained paste.
This is a method for producing an aqueous dispersion of self-dispersing colored fine particles, in which the obtained aqueous dispersion is filtered, membrane-separated or centrifuged to perform a post-treatment step of adjusting the concentration (Invention 5).

Further, the present invention is the method for producing an aqueous dispersion of the present invention 5, wherein the cumulative 90% particle size (P90) of the number conversion distribution is 50 nm or less in the dispersed particle size of the aqueous dispersion. a method of manufacturing an aqueous dispersion of a (invention 6).

Further, the present invention is a method for producing an aqueous dispersion according to the present invention 5 or 6, wherein in the dispersed particle size of the aqueous dispersion, the cumulative 90% particle size (P90) of the number conversion distribution and the cumulative number conversion distribution A method for producing an aqueous dispersion, wherein the particle size ratio (P90 / P50) to the 50% particle size (P50) is 5 or less (Invention 7).

In addition, the present invention provides a method for producing the self-dispersed colored fine particles obtained by the method for producing self-dispersed colored fine particles according to any one of the first to fourth inventions or the aqueous dispersion according to any one of the fifth to seventh inventions. Ink for ink jet recording using the aqueous dispersion obtained in the above (Invention 8).

Further, the present invention is obtained by the self-dispersing colored fine particles obtained by the method for producing self-dispersing colored fine particles according to any one of the first to fourth inventions or the method for producing an aqueous dispersion according to any of the fifth to seventh inventions. This is an ink for a color filter using the obtained aqueous dispersion (Invention 9).

  The self-dispersing colored fine particles according to the present invention are a composite color material comprising a water-insoluble color material and a hydrophilic color material in which a hydrophilic group is introduced into the color material having the same or similar structure as the water-insoluble color material, It has the function of dispersing in an aqueous dispersion medium without necessarily using a dispersant, the dispersion stability in the aqueous dispersion and ink is extremely good, excellent color development and transparency, fixing property, water resistance, light resistance Therefore, it is suitable as a color material that serves as an ink precursor for ink jet recording or color filters.

  Further, the aqueous dispersion according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, so that the dispersion stability at the time of preparing the ink itself and the ink is very good, and the color development and transparency are excellent. In addition, since an image having fastness such as fixability, water resistance, and light resistance can be expressed, it is suitable as a color material dispersion serving as an ink precursor for inkjet recording and color filters.

  Further, the ink for ink jet recording according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, or an aqueous dispersion, so that the dispersion stability is extremely good, and the color developability and transparency are excellent. Since an image having fastness such as fixing property, water resistance and light resistance can be expressed, it is suitable as an ink for ink jet recording.

  Further, the color filter ink according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, or an aqueous dispersion, so that the dispersion stability is extremely good, and the color developability and transparency are excellent. Since an image having fastness such as fixing property, water resistance and light resistance can be expressed, it is suitable as an ink for a color filter.

  The configuration of the present invention will be described in more detail as follows.

  First, the self-dispersing colored fine particles according to the present invention will be described.

  The self-dispersing colored fine particles according to the present invention are essentially the same as the water-insoluble colorant, which is difficult to disperse in an aqueous dispersion medium without a dispersant such as a surfactant or a water-soluble resin. Alternatively, a composite color material is obtained by combining a water-soluble hydrophilic color material in which a hydrophilic group is introduced into a color material having a similar structure. This is colored fine particles having an ultrafine particle size that does not necessarily dissolve in an aqueous dispersion medium, does not necessarily require a dispersant such as a surfactant or a water-soluble resin, and can be self-dispersed in an aqueous dispersion medium.

  The composite color material in the present invention is a compound in which particles are formed by mixing a water-insoluble color material and a hydrophilic color material simultaneously in water to form a mixed crystal or inclusion complex. It is estimated that As a result, unlike the hydrophilic color material alone, it does not dissolve in the aqueous dispersion medium, and unlike the water-insoluble color material, it has a function of being ultrafinely dispersed in the aqueous dispersion medium.

  The ratio of the water-insoluble colorant and the hydrophilic colorant in the self-dispersing colored fine particles is preferably 2% by weight or more and 100% by weight or less with respect to the water-insoluble colorant. When the ratio of the hydrophilic color material is less than 2% by weight with respect to the water-insoluble color material, it becomes difficult to disperse in the aqueous dispersion medium. On the other hand, when the ratio of the hydrophilic color material exceeds 100% by weight, the excessive hydrophilic color material is dissolved in the aqueous dispersion medium, and the same behavior as that of the dye occurs. More preferably, it is 10 weight% or more and 75 weight% or less, More preferably, it is 15 weight% or more and 60 weight% or less.

  As the water-insoluble colorant of the colored resin fine particles according to the present invention, any material can be used as long as it is insoluble in the aqueous dispersion medium and can achieve the present invention. More preferably, the water-insoluble colorant that does not change in quality during the micronization operation is preferable. Specifically, organic pigments, oil-soluble dyes, disperse dyes, vat dyes, and the like that are used as colorants for printing inks, paints, and resin compositions can be used.

  The water-insoluble colorant may be used at the same time depending on the required hue. Further, two or more kinds of similar colors may be used depending on the required hue and characteristics.

  Examples of the organic pigment include Pigment-Red 1, 2, 3, 4, 5, 6, 8, 9, 12, 14, 15, 16, 17, 19, 21, 22, 23, 31, 32, 37, 38, 41. 48, 48: 1, 48: 2, 48: 3, 48: 4, 49, 49: 1, 49: 2, 50: 1, 52, 52: 1, 52: 2, 53, 53: 1, 53 : 2, 53: 3, 57, 57: 1, 58: 4, 60, 63: 1, 63: 2, 64: 1, 68, 81, 81: 1, 81: 2, 81: 3, 81: 4 83, 88, 90: 1, 97, 112, 114, 122, 123, 144, 146, 147, 149, 150, 151, 166, 168, 169, 170, 171, 172, 173, 174, 175, 176 177, 178, 179, 180, 181, 184, 185, 187, 88, 190, 191, 192, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 215, 216, 217, 219, 220, 221, 223, 224, 226, 227, 228, 238, 240, 242, 243, 245, 247, 251, 253, 254, 255, 256, 257, 258, 260, 262, 263, 264, 266, 267, 268, 269, 270, 272, 273, 274, 279, Pigment-Blue 1, 1: 2, 9, 14, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 5, 15: 6, 16, 17: 1, 18, 19, 22, 24, 25, 27, 56, 56: 1, 57, 60, 61, 61: 1, 62, 63, 64, 66, 80, 88, Pigment Yellow 1, 2, 3, 4, 5, 6, 9, 10, 12, 13, 14, 16, 17, 20, 24, 55, 61, 62, 62: 1, 63, 65, 73, 74, 75, 81, 83, 86, 87, 88, 93, 94, 95, 97, 98, 99, 100, 101, 102, 104, 105, 108, 109, 110, 111, 115, 116, 117, 120, 123, 125, 126, 127, 128, 129, 130, 133, 137, 138, 139, 147, 148, 150, 151, 152, 153, 154, 155, 156, 166, 167, 168, 169, 170, 172, 173, 174, 175, 176, 180, 181, 182, 183, 185, 188, 191, 192, 193, 194, 196, 198, 199, 202 , 203, 213, 214, Pigment-Black 1, 20, 31, 32, Pigment-Green 1, 7, 8, 10, 36, Pigment-Orange 1, 2, 5, 13, 16, 17, 22, 24, 34, 36 38, 43, 48, 49, 51, 55, 59, 61, 62, 64, 66, 67, 69, 70, 71, 72, 73, 74, 77, Pigment-Violet 3, 19, 23, 25, 29 30, 31, 32, 37, 39, 40, 42, 50, Pigment-Brown 1, 23, 25, 27, organic fluorescent pigment (fluorescent dye / synthetic resin solid solution), and the like.

  As the oil-soluble dye, Solvent-Red 1, 2, 3, 4, 8, 13, 18, 23, 24, 25, 26, 27, 30, 32, 43, 44, 45, 49, 51, 52, 60, 72, 73, 79, 89, 91, 92, 109, 111, 122, 124, 127, 132, 135, 146, 168, 179, 195, 197, 218, 242, Solvent-Blue 2, 4, 5, 6, 8, 11, 13, 23, 24, 35, 36, 38, 44, 45, 59, 70, 74, 78, 104, 122, 124, Solvent-Yellow 2, 5, 6, 7, 14, 15, 16, 18, 19, 21, 29, 33, 44, 51, 56, 62, 72, 79, 82, 83, 83: 1, 93, 98, 114, 116, 133, 145, 163, 167, 17 Solvent-Black 3, 5, 7, 27, 29, 34, 45, Solvent-Green 1, 3, 5, 7, 28, Solvent-Orange 2, 60, 63, 41, 45, 54, 60, 62, 63, 86 Solvent-Violet 3, 8, 9, 11, 13, 31, 37, 49, 56, 59, Solvent-Brown 1, 41, 43, 53, and the like.

  Disperse dyes include Disperse-Red 1, 4, 11, 13, 50, 54, 58, 60, 72, 73, 74, 82, 86, 88, 91, 92, 93, 111, 126, 127, 134, 135. , 143, 145, 146, 152, 153, 154, 159, 164, 167, 167: 1, 177, 179, 181, 191, 204, 206, 207, 221, 239, 240, 258, 277, 278, 283 311, 323, 343, 348, 356, 362, 364, Disperse-Blue 3, 7, 14, 35, 56, 60, 72, 73, 77, 79, 87, 106, 113, 128, 143, 148, 154 158, 165, 165: 1, 165: 2, 176, 183, 185, 197, 198, 201, 214, 2 4, 225, 257, 266, 267, 284, 287, 291, 301, 354, 358, 359, 365, 366, 367, 368, Disperse Yellow 3, 5, 23, 42, 54, 64, 79, 82, 83, 93, 99, 100, 114, 119, 121, 122, 124, 126, 134, 160, 184, 184: 1, 186, 198, 199, 204, 224, 237, 211, 241, Disperse-Green 6: 1, 9, Disperse-Orange 1, 3, 11, 25, 29, 30, 31, 31: 1, 33, 44, 49, 54, 66, 73, 118, 119, 163, Disperse-Violet 1, 26, 33, 35, 63, 77, 93, 96, Disperse-Brown 1, 19 And the like.

  As vat dyes, Vat-Red 1, 10, 13, 14, 15, 23, 29, 31, 41, Vat-Blue 1, 4, 6, 20, 43, Vat-Yellow 1, 2, 4, 10, 12, 27, 29, 33, Vat-Black 16, 25, 27, 29, Vat-Green 1, 3, 8, 9, Vat-Orange 1, 2, 3, 4, 7, 9, 11, 15, 16, Vat-Violet 1, 9, Vat-Brown 1, 3, 5, 57, and the like.

  The hydrophilic coloring material in the present invention imparts hydrophilicity to a water-insoluble coloring material by substituting one or more anionic, cationic and nonionic functional groups in various reactions. However, it is prepared so that it can be dissolved or easily dispersed in an aqueous dispersion medium, and it may be prepared or commercially available.

  The hydrophilic color material in the present invention is preferably a color material having the same or similar structure as the water-insoluble color material. Examples of similar structures include the same basic structures such as free base phthalocyanine, iron phthalocyanine and zinc phthalocyanine for copper phthalocyanine, different quinacridones such as dimethylquinacridone and dichloroquinacridone, indanthrene and benz Examples thereof include imidazolone dioxazine or those having similar structures such as phthalocyanine and porphyrin, carbon black and phthalocyanine, quinacridone and diketopyrrolopyrrole, or heteroindole such as isoindolinone and benzimidazolone.

Examples of the anionic functional group introduced into the hydrophilic color material in the present invention include a sulfonic acid group, a sulfate ester group, a carboxyl group, and a phosphate ester group. Examples of the cationic functional group include an amino group, a hydrazine group, a pyridine group, an imidazole group, and a pyrrole group. Examples of the nonionic functional group include a hydroxyl group, a thiol group, a polyethylene glycol group, a polypropylene glycol group, a sulfoxide group, and a sulfoamide group.
For example, for quinacridone (CI Pigment-Violet 19 and CI Pigment-Red 122), Indigo (CI Pigment-Blue 66), and Indanthrone (CI Pigment-Blue 60), sulfonic acid Groups, carboxyl groups, amino groups, and the like, and combinations of sulfonic acid groups, hydroxyl groups, and the like can be used for benzimidazole (Pigment-Yellow 180).

  The self-dispersing colored fine particles according to the present invention preferably have a cumulative 10% particle size (D10) of the particle size distribution of 5 nm or more, more preferably 10 to 30 nm in the number distribution particle size. The cumulative 50% particle size (D50) of the particle size distribution is preferably 40 nm or less, more preferably 15 to 38 nm. In addition, the cumulative 90% particle size (D90) of the particle size distribution is preferably 50 nm or less, more preferably 20 to 48 nm or less, still more preferably 20 to 47 nm or less.

  The self-dispersing colored fine particles according to the present invention preferably have a ratio (D90 / D50) of a cumulative 90% particle diameter (D90) to a cumulative 50% particle diameter (D50) of 5 or less in the number distribution particle diameter. , More preferably 4 or less, even more preferably 3 or less.

  The average crystallite size of the self-dispersing colored fine particles according to the present invention is preferably 25 nm or less. When the average crystal size exceeds 25 nm, sufficient transparency cannot be exhibited. More preferably, it is 24 nm or less, More preferably, it is 23 nm or less.

  Next, the aqueous dispersion according to the present invention will be described.

  The aqueous dispersion according to the present invention has a surface activity in the aqueous dispersion medium by introducing the self-dispersing colored fine particles into the aqueous dispersion medium or neutralizing the charge of the hydrophilic group introduced into the aqueous dispersion medium. It is an aqueous dispersion that can be easily self-dispersed in an aqueous dispersion medium without using a dispersant such as an agent or a water-soluble resin.

  In the aqueous dispersion according to the present invention, water and, if necessary, a water-soluble organic solvent can be used as the aqueous dispersion medium. The ratio of the water-soluble organic solvent to 100 parts by weight of water in the aqueous dispersion is preferably 1 to 50 parts by weight, more preferably 1 to 30 parts by weight.

  Water-soluble organic solvents include methanol, ethanol, 1-propanol, 2-propanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tetraethylene glycol, hexylene glycol, polyethylene glycol, polypropylene glycol, 1, Polyhydric alcohols such as 3-butanediol, 1,5-pentanediol, 1,6-hexanediol, glycerol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether , Triethylene glycol monomethyl ether, triethylene glycol Polyhydric alcohol alkyl ethers such as ethyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, polyhydric alcohol allyl ethers such as ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether, N-methylpyrrolidone, 1,3- Nitrogen-containing heterocyclic compounds such as dimethylimidazolidinone and γ-butyrolaclone, amides such as N, N-dimethylformamide and urea, amines such as monoethanolamine, diethanolamine and triethanolamine, thiodiethanol, sulfolane and dimethyl Sulfur-containing compounds such as sulfoxide are used and may be used alone or in combination.

  In the aqueous dispersion according to the present invention, a pH adjusting agent can be added to neutralize the charge of the introduced hydrophilic group. When a hydrophilic colorant having an anionic group is introduced, inorganic salts such as sodium hydroxide, potassium hydroxide and lithium hydroxide, or ammonia, trimethylamine, ethylamine, diethylamine, triethylamine, N-methyl Diethylamine, morpholine, N, N-dimethylaminoethanol, N, N-diethylaminoethanol, 2-amino-2-methyl-1-propanol, monoethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, diisopropanolamine, diethanolamine Organic amines such as triethanolamine are used, and may be used alone or mixed. When a hydrophilic colorant having a cationic group is introduced, inorganic salts such as hydrochloric acid, sulfuric acid, phosphoric acid, boric acid, formic acid, acetic acid, propionic acid, butyric acid, oxalic acid, phthalic acid, fumaric acid Organic acids such as ascorbic acid are used.

  The aqueous dispersion according to the present invention preferably has a 10% cumulative particle size (P10) of the number conversion distribution in the dispersed particle diameter of 5 nm or more, more preferably 10 to 30 nm. Further, the cumulative 50% particle size (P50) of the number conversion distribution is preferably 40 nm or less, more preferably 15 to 38 nm. The cumulative 90% particle size (P90) of the number conversion distribution is preferably 50 nm or less, more preferably 20 to 48 nm.

  In the aqueous dispersion according to the present invention, the ratio (P90 / P50) of the cumulative 90% particle size (P90) to the cumulative 50% particle size (P50) of the particle size distribution is preferably 5 or less. When the ratio exceeds 5, scattered light may be generated and transparency may be lowered. More preferably, it is 3 or less, and still more preferably 2 or less.

  The viscosity of the aqueous dispersion according to the present invention is preferably 10.0 mPa · s or less. When the viscosity exceeds 10.0 mPa · s, the viscosity of the ink prepared using this increases, which is not preferable. More preferably, it is 8.0 mPa · s or less. The lower limit is about 1.0 mPa · s.

  The content of the self-dispersing colored fine particles in the aqueous dispersion according to the present invention is preferably 1 to 40%. If it is less than 1%, it is difficult to use it as an ink in various applications because the colorant concentration is dilute. When it exceeds 40%, it becomes difficult to sufficiently disperse. More preferably, it is 2 to 30%.

  The surface tension of the aqueous dispersion according to the present invention is preferably 55 mN / m or more, more preferably 60 mN / m or more.

  Next, a method for producing self-dispersed colored fine particles and an aqueous dispersion according to the present invention will be described.

As a method for obtaining a water-insoluble colorant having a particle size of several tens of nanometers, there are usually a downsizing method and a buildup method. Among them, a downsizing method in which particles are refined by a mechanical force using a pulverizing and dispersing machine such as a bead mill and a roll mill has been used conventionally. In the downsizing method, as described above, when primary particles used are pulverized by mechanical force, it is called overdispersion due to an increase in specific surface area and a local change in the crystal structure of the colorant surface. Disperse unstable color material. Therefore, a build-up method in which particles are formed from a dissolved state without pulverization has been studied.
In the present invention, a water-insoluble colorant and a hydrophilic colorant are dissolved in an aprotic polar organic solvent and injected into water, so that the aqueous dispersion medium is self-dispersed without using a dispersant such as a surfactant or a water-soluble resin. Self-dispersed colored fine particles and aqueous dispersions having a particle size of several tens of nanometers can be prepared.

  The self-dispersing colored fine particles and the aqueous dispersion in the present invention can be obtained through the steps of hydrophilic colorant preparation, dissolution reprecipitation step, concentration dialysis step, redispersion step and post-treatment step in order.

The hydrophilic color material preparation is a step of preparing a hydrophilic color material. The method for introducing a hydrophilic group may be carried out according to a conventional method, but as a simple method, sulfonation and carboxylation are exemplified for an anionic group, and amination is exemplified for a cationic group.
For example, as a sulfonation method, a sulfonic acid group can be easily substituted on the benzene ring portion by dissolving various colorants in a strong acid such as sulfuric acid and contacting with a sulfonating agent such as fuming sulfuric acid. As a method for carboxylation, a carboxyl group can be easily substituted on the benzene ring portion by reacting various color materials with n-butyllithium and then reacting with carbon dioxide. As an amination method, various colorants are dissolved in a strong acid such as sulfuric acid, nitrated by contacting with a nitrating agent such as nitric acid, and then aminated by hydrogen reduction. In addition, when the water-insoluble coloring material contains a nitrogen atom or the like, a carboxyl group such as phthalic acid or an amino group such as ethylenediamine can be extended from this nitrogen. Furthermore, based on the above functional groups, sulfate groups, phosphate groups, hydrazine groups, pyridine groups, imidazole groups, pyrrole groups, polyethylene glycol groups, and the like can be substituted.
When a commercially available hydrophilic color material such as sulfonated phthalocyanine or sulfonated indigo (indigo carmine) is used, it is not necessary to prepare it again.

  The dissolution and reprecipitation step is a step of obtaining a crude of self-dispersed colored fine particles by dissolving a water-insoluble colorant and a hydrophilic colorant in an aprotic polar solvent and putting them in an aqueous dispersion medium.

  As the aprotic polar organic solvent, any water-insoluble colorant and colorant having a hydrophilic group introduced into the water-insoluble colorant can be dissolved at the same time, and any solvent that can achieve the object of the present invention can be used. is there. Specifically, dimethylsulfoxide, dimethylimidazolidinone, sulfolane, N-methylpyrrolidone, dimethylformamide, acetonitrile, acetone, dioxane, tetramethylurea, hexamethylphosphoramide, hexamethylphosphorofuran, tetrahydrofuran, tetrahydropyran, Ethylene glycol diacetate, γ-butyl lactone and the like are mentioned as preferred solvents. Among them, dimethyl sulfoxide, N-methylpyrrolidone, dimethylformamide, dimethylimidazolidinone, sulfolane, acetone or acetonitrile are preferred. Moreover, these can be used individually by 1 type or in combination of 2 or more types.

  The proportion of the aprotic polar organic solvent used is not particularly limited, but from the viewpoint of a better dissolved state of the water-insoluble colorant and the ease of formation of the desired self-dispersing colored fine particles, It is preferably used in an amount of 5 to 1000 parts by weight based on 1 part by weight of both or at least one of the insoluble colorant and the colorant having a hydrophilic group introduced into the water-insoluble colorant.

  When preparing a solution dissolved in the aprotic polar organic solvent, a hydrophilic group was introduced into the colorant water-insoluble colorant and the water-insoluble colorant under heating at normal temperature or near the maximum boiling point of normal pressure. It is preferable to dissolve both or at least one of the color materials.

  In addition, a self-dispersing type is obtained by contacting a water-insoluble colorant and / or a colorant in which a hydrophilic group is introduced into the water-insoluble colorant, or a solution obtained by dissolving at least one in an aprotic polar organic solvent with an aqueous dispersion medium. It becomes possible to deposit colored fine particles. The ratio of the aqueous dispersion medium used in this case is, from the viewpoint of ease of forming desired self-dispersing colored fine particles, both the water-insoluble colorant and the colorant introduced with a hydrophilic group in the water-insoluble colorant, or at least The amount is preferably 1 to 1000 parts by weight with respect to 1 part by weight of a solution obtained by dissolving one in an aprotic polar organic solvent.

  Further, when the water-insoluble colorant and the colorant having a hydrophilic group introduced into the water-insoluble colorant, or a solution obtained by dissolving at least one in an aprotic polar organic solvent is brought into contact with an aqueous medium. It is preferable to adjust the freezing point above the freezing point of the aprotic polar organic solvent and below the maximum boiling point of the aqueous medium.

  Further, in order to maintain the desired size uniformity of the fine colored fine particles, it is preferable to make contact with the aqueous dispersion medium as quickly as possible. Conventionally known methods such as an ultrasonic vibrator and a circulation type stirring device are known. Any apparatus used for stirring, mixing, and dispersing can be used. In addition, as a method for contacting in the aqueous dispersion medium, any of the conventionally known liquid injection methods can be used, but it is preferable to spray from a nozzle as fine as possible such as a syringe or a needle and contact in an aqueous medium.

  The concentration dialysis step is a step of adjusting the colorant concentration by concentrating and dialyzing the obtained self-dispersing colored fine particle crude and removing aprotic polar organic solvents, salts and impurities contained in the system. is there.

  The apparatus used for the concentration dialysis step is not particularly limited, but ultrafiltration, filtration such as ceramic filter and crossflow filtration, and membrane separation such as reverse osmosis membrane are preferable.

  In the redispersion step, dispersion is performed in the aqueous dispersion medium without adding a dispersant or the like by adding the aqueous dispersion medium, basic substance, or acidic substance to the paste concentrated and dialyzed in the previous step. This is a step of obtaining a water-based dispersion containing self-dispersing colored fine particles (self-dispersing). At this time, in order to increase the dispersion effect, it is possible to perform simple dispersion by stirring with a stirring blade, a homogenizer, a homomixer, or an ultrasonic homogenizer.

  In the post-treatment step, coarse particles and impurities contained in the obtained aqueous dispersion containing self-dispersed colored fine particles are filtered or membraneed using ultrafiltration, ceramic filter, crossflow filtration membrane, reverse osmosis membrane, etc. Self-dispersion type by removing by separating or centrifuging, further diluting by adding ion exchange water or ultrafiltration, ceramic filter, cross-flow filtration membrane, reverse osmosis membrane, vacuum distillation etc. This is a step of adjusting the purity and concentration of the colored fine particles.

  In addition, although the aqueous dispersion which concerns on this invention has the outstanding dispersibility even if it does not use a dispersing agent, it can also be made higher dispersibility using a dispersing agent.

  In the present invention, when it is necessary to take out the self-dispersed colored fine particles, the aqueous dispersion after the post-treatment step may be filtered and dried by a conventional method.

  In the present invention, when an aqueous dispersion containing self-dispersing colored fine particles is required, the dispersion after the post-treatment process may be used as it is.

  Next, the ink for ink jet recording according to the present invention will be described.

  The inkjet recording ink according to the present invention is self-dispersed in 100 parts by weight of the inkjet recording ink by dispersing the self-dispersing colored fine particles according to the present invention in an aqueous solvent or diluting the aqueous dispersion according to the present invention. 1 to 40 parts by weight, preferably 2.5 to 20 parts by weight of mold-type fine particles are contained.

  The ink for ink jet recording according to the present invention comprises the self-dispersed colored fine particles according to the present invention, an aqueous dispersion and water, and includes a surfactant, a water-soluble organic compound, a pH adjuster, a preservative and the like as necessary. An additive may be contained.

  As the surfactant, an anionic surfactant or a nonionic surfactant can be used. Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, polyoxyethylene alkyl ether sulfate, dodecylbenzene sulfonate, and laurate. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkyl phenyl ether, polyoxyethylene alkylamide, 2,4,7,9-tetramethyl. Acetylene glycols such as -5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, 3,5-dimethyl-1-hexyn-3-ol (for example, manufactured by Air Products) Surfinol 104, 420, 440, 465, 485, etc.) can be used, and one or a mixture of two or more can be used.

  Examples of water-soluble organic compounds include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tetraethylene glycol, hexylene glycol, polyethylene glycol, polypropylene glycol, 1,3-butanediol, and 1,5-pentanediol. , 1,6-hexanediol, glycerol, polyhydric alcohol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol mono Ethyl ether, triethylene glycol monobutyl ether Polyhydric alcohol alkyl ethers such as tetraethylene glycol monomethyl ether, polyhydric alcohol allyl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, Nitrogen-containing heterocyclic compounds such as γ-butyrolacron, amides such as N, N-dimethylformamide and urea, amines such as monoethanolamine, diethanolamine and triethanolamine, sulfur-containing compounds such as thiodiethanol, sulfolane and dimethylsulfoxide Compound, glucose, mannose, fructose, ribose, xylose, arabinose, galactose, maltose, cellobiose, lactose, sucrose, trehalose, cellulose, Sugars such as dextrin and cyclodextrin are used and may be used alone or in combination.

  Examples of pH adjusters include inorganic salts such as sodium hydroxide, potassium hydroxide and lithium hydroxide, or ammonia, trimethylamine, ethylamine, diethylamine, triethylamine, N-methyldiethylamine, morpholine, N, N-dimethylaminoethanol, N , N-diethylaminoethanol, 2-amino-2-methyl-1-propanol, monoethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, diisopropanolamine, diethanolamine, triethanolamine and other organic amines or hydrochloric acid, Inorganic salts such as sulfuric acid, phosphoric acid and boric acid, organic acids such as formic acid, acetic acid, propionic acid, butyric acid, succinic acid, phthalic acid, fumaric acid and ascorbic acid are used. Also There.

  As preservatives, alkylisothiazolones, chloroalkylisothiazolones, benzisothiazolones, bromonitroalcohols, oxazolidines, chloroxylenols and the like are used as necessary, and these may be used alone or in combination.

  The dispersed particle size of the ink for ink jet recording in the present invention is preferably 5 nm or more, more preferably 10 to 30 nm, as the cumulative 10% particle size (P10) of the number conversion distribution. Further, the cumulative 50% particle size (P50) of the number conversion distribution is preferably 40 nm or less, more preferably 15 to 38 nm. The cumulative 90% particle size (P90) of the number conversion distribution is preferably 50 nm or less. When it exceeds 50 nm, scattered light is generated and transparency cannot be exhibited. More preferably, it is 20-48 nm.

  In the dispersed particle size of the inkjet recording ink in the present invention, the ratio (P90 / P50) of the cumulative 90% particle size (P90) to the cumulative 50% particle size (P50) of the number conversion distribution is 5 or less. preferable. When the particle size ratio exceeds 5, scattered light may be generated and transparency may be lowered. More preferably, it is 3 or less, and still more preferably 2 or less.

  The viscosity of the inkjet recording ink in the invention is preferably 10.0 mPa · s or less. When the viscosity exceeds 10.0 mPa · s, a printed image having a clear hue cannot be obtained. More preferably, it is 5.0 mPa · s or less, and the lower limit is about 1.5 mPa · s.

  The dispersion stability of the ink for ink jet recording in the present invention is preferably 7% or less, more preferably 6% or less, and still more preferably 5% or less in the rate of change of the dispersed particle diameter after one week. Further, the rate of change in viscosity after 1 week is preferably 10% or less, more preferably 8% or less, and still more preferably 6% or less.

  Next, a method for producing an inkjet recording ink using the self-dispersing colored fine particles or the aqueous dispersion according to the present invention will be described.

  The ink for inkjet recording according to the present invention comprises a predetermined amount of the self-dispersing colored fine particles or aqueous dispersion according to the present invention, ion-exchanged water, and if necessary, a surfactant, a water-soluble organic compound, a pH adjuster, and a preservative. It is obtained by mixing with additives such as, and then filtering and / or centrifuging using a membrane filter.

  Next, the color filter ink according to the present invention will be described.

  The color filter ink according to the present invention is preferably 1 to 40 parts by weight of the self-dispersing colored fine particles in 100 parts by weight of the color filter ink by diluting the self-dispersing colored fine particles or the aqueous dispersion according to the present invention. Contains 2.5 to 20 parts by weight.

  The color filter ink according to the present invention comprises the self-dispersed colored fine particles or the aqueous dispersion according to the present invention and water, and if necessary, has the same interface as described in the resin aqueous solution, resin emulsion, and ink jet recording ink. You may contain additives, such as an activator, a water-soluble organic compound, a pH adjuster, and antiseptic | preservative.

  Examples of the resin include polyvinyl alcohol, polyacrylamide, acrylic polymer, polyester, urethane, fluororesin, and melamine resin.

  Next, a method for producing the color filter ink according to the present invention will be described.

  The color filter ink according to the present invention comprises a predetermined amount of the self-dispersing colored fine particles or water-based dispersion according to the present invention, ion-exchanged water, and if necessary, a resin aqueous solution, a resin emulsion, a surfactant, a water-soluble organic compound, It is prepared by mixing additives such as pH adjusters and preservatives, and then filtering and / or centrifuging using a membrane filter.

<Action>
The self-dispersing colored fine particles according to the present invention are colored fine particles made of a composite color material of a water-insoluble color material and a hydrophilic color material. This composite color material state controls the hydrophilicity and hydrophobicity, and exhibits the ability to self-disperse without using a surfactant or a dispersant. Furthermore, in the printing characteristics, since the coloring component is a fine particle, there is no light reflection or light scattering peculiar to a water-insoluble colorant while maintaining the light resistance and water resistance as a water-insoluble colorant, and transparency close to a dye. Exhibits color development.

  Since the aqueous dispersion according to the present invention is composed of self-dispersing colored fine particles having the characteristics as described above, it exhibits a high degree of dispersion stability, while maintaining light resistance and water resistance as a water-insoluble colorant. There is no light reflection or light scattering peculiar to water-insoluble colorants, and it exhibits transparency and color development similar to dyes.

  The ink for ink jet recording according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, or an aqueous dispersion, so that it exhibits high dispersion stability and high ink ejection stability in an ink jet system. While maintaining light resistance and water resistance as a water-insoluble color material, there is no light reflection or light scattering peculiar to water-insoluble color materials, and it exhibits transparency and color development similar to dyes.

  The color filter ink according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, or an aqueous dispersion, so that it exhibits a high degree of dispersion stability and is light resistant as a water-insoluble colorant. While maintaining water resistance, there is no light reflection or light scattering peculiar to water-insoluble colorants, and it exhibits transparency and color development similar to dyes.

  Next, the present invention will be described in more detail with reference to examples. In the text, “parts” and “%” are based on weight. The present invention is not limited by the following examples.

The infrared absorption spectrum was measured by a KBr method using a Shimadzu Fourier transform infrared spectrophotometer FTIR-8700.
The average particle size is 10% of the total number distribution calculated by the image analysis software and analysis pro made by Soft Imaging System based on the transmission image of the particles taken with a transmission electron microscope JEM1200EX02 (TEM) manufactured by JASCO. Displayed by value (D10), 50% value (D50), 90% value (D90).
The average crystallite size was estimated by the Scherrer method based on the X-ray diffraction spectrum measured by the RINT2500 X-ray diffractometer manufactured by Rigaku Corporation.
The dispersed particle size of the aqueous dispersion was measured with a dense particle size distribution analyzer FPAR-1000 manufactured by Otsuka Electronics Co., Ltd. and displayed as a cumulative 10% value (P10), 50% value (P50), and 90% value (P90) of the number conversion distribution. It was done.
The viscosity was measured with an E-type viscometer TV-30 manufactured by Toki Sangyo.
The surface tension was measured with a Du Nuit surface tension meter manufactured by Nippon Oil Testing Machine Industry.
The visible absorption spectrum was measured by Shimadzu autograph spectrophotometer UV-2100. Furthermore, the concentrations of the dispersion and the ink were calculated by measuring the extinction coefficient at the maximum wavelength of the visible absorption spectrum and comparing it with the extinction coefficient of each water-insoluble colorant.

(Preparation of hydrophilic coloring material 1)
A C.I. solution dissolved in 60 parts by weight of 98% sulfuric acid in a three-necked flask equipped with a dropping funnel, a condenser and a thermometer. I. Pigment-Red122 and 5 parts by weight were added, and 40 parts of 25% fuming sulfuric acid was added from a dropping funnel over 10 minutes. This solution was heated to 80 ° C. in an oil bath, stirred for 5 hours, and poured into ice water to obtain a precipitate. This precipitate was filtered, washed with ion-exchanged water and methanol, and dried to obtain 5 parts by weight of hydrophilic coloring material 1 (sulfonic acid group addition compound of CI Pigment-Red 122).

(Preparation of hydrophilic coloring material 2)
Into a three-necked flask equipped with a dropping funnel, condenser and thermometer, C.I. I. Pigment-Red 122, 5 parts by weight, and 100 parts by weight of dry dimethylformamide were added and suspended. After substituting the system with argon, 2 parts by weight of sodium hydride (as 60% mineral oil dispersion) was dropped from the dropping funnel and stirred to confirm that the suspension became a solution. Next, 4.5 parts by weight of phthalic anhydride dissolved in dimethylformamide was added dropwise and stirred at 80 ° C. for 3 hours. Thereafter, the mixture was allowed to cool to room temperature, concentrated with an evaporator, extracted and washed with water and ethyl acetate. Further purified by flash column chromatography (15 × 300 mm; Wakogel C300; effluent = diethyl ether: hexane = 2-3: 8), dried, and hydrophilic coloring material 2 (carboxyl group-added compound of CI Pigment-Red122) 5 parts by weight were obtained.

(Preparation of hydrophilic coloring material 3)
Into a three-necked flask equipped with a dropping funnel, condenser and thermometer, C.I. I. Pigment-Red 122, 5 parts by weight, and 100 parts by weight of dry dimethylformamide were added and suspended. After substituting the system with argon, 2 parts by weight of sodium hydride (as 60% mineral oil dispersion) was dropped from the dropping funnel and stirred to confirm that the suspension became a solution. Next, 5.7 parts by weight of 1,2-dibromoethane was added and stirred at 80 ° C. for 3 hours. And 3 weight part of ethylenediamine was dripped, and also it stirred at 80 degreeC for 15 hours. Thereafter, the mixture was allowed to cool to room temperature, concentrated with an evaporator, extracted and washed with water and ethyl acetate. Further, it was purified by flash column chromatography (15 × 300 mm; Wakogel C300; effluent = diethyl ether: hexane = 2: 3: 8), dried, and hydrophilic coloring material 3 (an amino group addition compound of CI Pigment-Red122). 5 parts by weight were obtained.

(Hydrophilic coloring material 4)
Commercially available indigo carmine (a sulfonic acid group addition compound of CI Pigment-Blue 66) was used as the hydrophilic coloring material 4.

(Preparation of hydrophilic coloring material 5)
C. I. Pigment-Red122 as C.I. I. Except having changed to Pigment-Yellow180, it carried out similarly to preparation of the hydrophilic coloring material 1, and obtained 5 weight part of hydrophilic coloring materials 5 (sulfonic acid group addition compound of CI Pigment-Yellow180).

[Example 1] (C. I. Pigment-Violet 19 self-dispersed colored fine particles and aqueous dispersion)
<Dissolution reprecipitation step> 4500 parts by weight of ion-exchanged water was placed in a vessel equipped with a stirring blade and stirred at 8000 rpm. Next, hydrophilic coloring material 1, 1 part by weight and C.I. I. Pigment-Violet 19, 1 part by weight is dissolved in 500 parts by weight of N-methylpyrrolidone, and this solution is rapidly poured into the ion-exchanged water being stirred through a 0.2 mm needle opening to obtain a highly transparent magenta liquid. It was.
<Concentration dialysis step> This magenta solution was concentrated using an ultrafiltration membrane having a fractional molecular weight of 20,000. Further, dialysis with ion-exchanged water was continuously performed to remove N-methylpyrrolidone contained in the system, impurities, and the hydrophilic coloring material dissolved in water to obtain a colored paste.
<Redispersion step> A 1 mol / kg sodium hydroxide aqueous solution and ion-exchanged water were added to this colored paste and stirred to disperse to obtain an aqueous dispersion having a pH of 8.5. It is obvious that the colored fine particles contained in this aqueous dispersion are self-dispersing because they are dispersed without adding a dispersant.
<Post-processing step> This aqueous dispersion is subjected to centrifugation (5000 rpm), and further filtered through a 0.8 mm Millipore filter to remove coarse particles contained in the aqueous dispersion, and ion-exchanged water is added to the coloring material. By adjusting the concentration to 10%, an aqueous dispersion of self-dispersing colored fine particles in the present invention was obtained. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersed colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2500 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic coloring material 1, and it has been clarified that the self-dispersing colored fine particles are a composite coloring material of a water-insoluble coloring material and a hydrophilic coloring material.
In terms of number distribution, the 10% cumulative particle size (D10) was 18 nm, the cumulative 50% particle size (D50) was 33 nm, and the cumulative 90% particle size (D90) was 35 nm.
When the X-ray diffraction spectrum of the self-dispersing colored fine particles was measured and the average crystallite size was estimated, it was 18 nm. Further, the crystal form is β type, and C.I. as shown in Comparative Examples 1 and 2 or Patent Document 5. I. It was clearly different from that of the γ-type crystal form obtained by <dissolution reprecipitation step> with Pigment-Violet 19 alone. This is because the hydrophilic coloring material 1 is incorporated into the particles (crystals), and thus C.I. I. It shows that the crystal formation of Pigment-Violet 19 is changed. From these results, it has been clarified that the hydrophilic coloring material does not affect only the crystal surface but greatly contributes to the formation of a molecular arrangement inside the crystal.
The dispersed particle diameter of the aqueous dispersion was a number conversion distribution. The cumulative 10% particle diameter (P10) was 25 nm, the cumulative 50% particle diameter (P50) was 35 nm, and the cumulative 90% particle diameter (P90) was 42 nm. The viscosity was 5 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 515 nm, indicating a magenta color.

Further, in order to analyze the composition of the self-dispersing colored fine particles, the following analysis was performed.
0.10 parts by weight of self-dispersing colored fine particles were collected and dissolved in 5 parts by weight of N-methylpyrrolidone. When this solution was subjected to silica gel column chromatography (15 × 300 mm; Wakogel C300; effluent = ethyl acetate: hexane = 8: 2) to separate the color material, the water-insoluble color material C.I. I. Pigment-Violet 19 was 0.08 part by weight, and hydrophilic coloring material 1 was 0.02 part by weight. From this, the hydrophilic colorant was 25% by weight based on the water-insoluble colorant.

Example 2 (CI Pigment-Red122 Self-Dispersion Colored Fine Particles and Aqueous Dispersion)
C. I. Pigment-Violet 19 is C.I. I. A water-based dispersion containing 10% of self-dispersing colored fine particles and self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that Pigment-Red 122 was used. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic coloring material 1, and it has been clarified that the self-dispersing colored fine particles are a composite coloring material of a water-insoluble coloring material and a hydrophilic coloring material.
The particle size was a number-converted distribution. The cumulative 10% particle size (D10) was 20 nm, the cumulative 50% particle size (D50) was 31 nm, and the cumulative 90% particle size (D90) was 38 nm. From the X-ray diffraction spectrum measurement, the average crystallite size was 12 nm.
The dispersed particle diameter of the aqueous dispersion was a number conversion distribution. The cumulative 10% particle diameter (P10) was 22 nm, the cumulative 50% particle diameter (P50) was 36 nm, and the cumulative 90% particle diameter (P90) was 45 nm. The viscosity was 5 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 515 nm, indicating a magenta color.
Furthermore, as a result of analyzing the composition in the same manner as in Example 1, the hydrophilic colorant was 18% by weight based on the water-insoluble colorant.

[Example 3] (CI Pigment-Red122 self-dispersed colored fine particles and aqueous dispersion)
C. I. Pigment-Violet 19 is C.I. I. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the hydrophilic colorant 1 was changed to Pigment-Red 122 to the hydrophilic colorant 2. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3000 to 2500 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a carboxyl group. This carboxyl group is derived from the hydrophilic color material 1, and it has been clarified that the self-dispersing colored fine particles are a composite color material of a water-insoluble color material and a hydrophilic color material.
The particle size was a number conversion distribution. The cumulative 10% particle size (D10) was 21 nm, the cumulative 50% particle size (D50) was 30 nm, and the cumulative 90% particle size (D90) was 40 nm. From the X-ray diffraction spectrum, the average crystallite size was 15 nm.
Further, the dispersed particle size of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (P10) is 22 nm, the cumulative 50% particle size (P50) is 31 nm, and the cumulative 90% particle size (P90) is 41 nm. It was. The viscosity was 5 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 514 nm, indicating a magenta color.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 25% by weight based on the water-insoluble colorant.

Example 4 (CI Pigment-Red 122 Self-Dispersion Colored Fine Particles and Aqueous Dispersion)
C. I. Pigment-Violet 19 is C.I. I. In Pigment-Red 122, the hydrophilic colorant 1 is changed to the hydrophilic colorant 3, and the 1 mol / kg sodium hydroxide aqueous solution added in the redispersion step is changed to a 1 mol / kg phosphoric acid aqueous solution to obtain a final pH of 5. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the acidity was adjusted to 5 (acidity 5). Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
The The infrared absorption spectrum of self-dispersible colored particles was measured, in addition to the absorption of two to 3360,3280Cm ^-1 spectral from water-insoluble colorant and a large absorption of one to 1600 cm ^-1 is observed , Identified as an amino group. This amino group is derived from the hydrophilic coloring material 3, and it was revealed that the self-dispersing colored fine particles are a composite coloring material of a water-insoluble coloring material and a hydrophilic coloring material.
The particle size was a number conversion distribution. The cumulative 10% particle size (D10) was 18 nm, the cumulative 50% particle size (D50) was 32 nm, and the cumulative 90% particle size (D90) was 42 nm. From the X-ray diffraction spectrum, the average crystallite size was 15 nm.
In addition, the dispersed particle diameter of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle diameter (P10) is 20 nm, the cumulative 50% particle diameter (P50) is 33 nm, and the cumulative 90% particle diameter (P90) is 45 nm. It was. The viscosity was 5 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 514 nm, indicating a magenta color.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 25% by weight based on the water-insoluble colorant.

[Example 5] (CI Pigment-Blue 66 self-dispersing colored fine particles and aqueous dispersion)
The hydrophilic color material 1 is changed to the hydrophilic color material 4 and C.I. I. Pigment-Violet 19 is C.I. I. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that Pigment-Blue 66 was used. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic coloring material 4, and it has been clarified that the self-dispersing colored fine particles are a composite coloring material of a water-insoluble coloring material and a hydrophilic coloring material.
The particle size was a number-converted distribution with a cumulative 10% particle size (D10) of 20 nm, a cumulative 50% particle size (D50) of 35 nm, and a cumulative 90% particle size (D90) of 39 nm. From the X-ray diffraction spectrum, the average crystallite size was 6 nm.
In addition, the dispersed particle size of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (P10) is 20 nm, the cumulative 50% particle size (P50) is 36 nm, and the cumulative 90% particle size (P90) is 40 nm. there were. The viscosity was 6 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 618 nm, indicating a fading color.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 25% by weight based on the water-insoluble colorant.

Example 6 (CI Pigment-Blue 60 Self-Dispersion Colored Fine Particles and Aqueous Dispersion)
The hydrophilic color material 1 is changed to the hydrophilic color material 4 and C.I. I. Pigment-Violet 19 is C.I. I. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the pigment was changed to Pigment-Blue 60. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic coloring material 4, and it has been clarified that the self-dispersing colored fine particles are a composite coloring material of a water-insoluble coloring material and a hydrophilic coloring material.
In terms of number distribution, the 10% cumulative particle size (D10) was 15 nm, the cumulative 50% particle size (D50) was 29 nm, and the cumulative 90% particle size (D90) was 35 nm. From the X-ray diffraction spectrum, the average crystallite size was 15 nm.
In addition, the dispersed particle size of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (P10) is 20 nm, the cumulative 50% particle size (P50) is 35 nm, and the cumulative 90% particle size (P90) is 41 nm. there were. The viscosity was 5 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 620 nm, indicating a fading color.
Further, as a result of analysis in the same manner as in Example 1, the hydrophilic colorant was 33% by weight based on the water-insoluble colorant.

Example 7 (CI Pigment-Red181 Self-Dispersing Colored Fine Particles and Aqueous Dispersion)
The hydrophilic color material 1 is changed to the hydrophilic color material 4 and C.I. I. Pigment-Violet 19 is C.I. I. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the pigment was changed to Pigment-Red181. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersed colored fine particles was measured, a wide small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic color material 4, and it has been clarified that the self-dispersing colored fine particles are a composite color material of a water-insoluble color material and a hydrophilic color material.
In terms of number distribution, the cumulative 10% particle size (D10) was 18 nm, the cumulative 50% particle size (D50) was 30 nm, and the cumulative 90% particle size (D90) was 38 nm. From the X-ray diffraction spectrum, the average crystallite size was 14 nm.
In addition, the dispersion particle size of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (P10) is 19 nm, the cumulative 50% particle size (P50) is 32 nm, and the cumulative 90% particle size (P90) is 38 nm. there were. The viscosity was 3 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 542 nm, indicating a red color.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 22% by weight based on the water-insoluble colorant.

Example 8 (CI Pigment-Yellow 180 Self-Dispersion Colored Fine Particles and Aqueous Dispersion)
1 to 1 part of the hydrophilic color material 5 to 0.5 part by weight of the hydrophilic color material C.I. I. Pigment-Violet 19, 1 part of C.I. I. Pigment-Yellow 180, an aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the amount was changed to 1 part by weight. Moreover, solid content was taken out from the obtained aqueous dispersion, washed with water and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic color material 5, and it has been clarified that the self-dispersing colored fine particles are a composite color material of a water-insoluble color material and a hydrophilic color material.
In terms of number distribution, the cumulative 10% particle size (D10) was 19 nm, the cumulative 50% particle size (D50) was 31 nm, and the cumulative 90% particle size (D90) was 38 nm. From the X-ray diffraction spectrum, the average crystallite size was 18 nm.
In addition, the dispersed particle size of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (P10) is 22 nm, the cumulative 50% particle size (P50) is 34 nm, and the cumulative 90% particle size (P90) is 38 nm. there were. The viscosity was 4 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 435 nm, indicating yellow.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 20% by weight based on the water-insoluble colorant.

Example 9 (CI Pigment-Yellow 74 Self-Dispersion Colored Fine Particles and Aqueous Dispersion)
Next, 1 part of the hydrophilic color material 1 and 2 parts of the hydrophilic color material C. I. Pigment-Violet 19, 1 part of C.I. I. Pigment-Yellow 74, an aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the amount was changed to 1 part. The solid content was taken out from the obtained aqueous dispersion, washed with water, and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic color material 5, and it has been clarified that the self-dispersing colored fine particles are a composite color material of a water-insoluble color material and a hydrophilic color material.
In terms of number distribution, the 10% cumulative particle size (D10) was 15 nm, the cumulative 50% particle size (D50) was 30 nm, and the cumulative 90% particle size (D90) was 39 nm. From the X-ray diffraction spectrum, the average crystallite size was 12 nm.
In addition, the dispersed particle size of the aqueous dispersion is a number conversion distribution in which the cumulative 10% particle size (P10) is 23 nm, the cumulative 50% particle size (P50) is 35 nm, and the cumulative 90% particle size (P90) is 44 nm. there were. The viscosity was 5 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 436 nm, indicating yellow.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 21% by weight with respect to the water-insoluble colorant.

[Example 10] (CI-Pigment-Blue 60 self-dispersing colored fine particle aqueous dispersion)
Next, the hydrophilic color material 1 is changed to the hydrophilic color material 5 and C.I. I. Pigment-Violet 19 is C.I. I. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the pigment was changed to Pigment-Blue 60. The solid content was taken out from the obtained aqueous dispersion, washed with water, and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic color material 5, and it has been clarified that the self-dispersing colored fine particles are a composite color material of a water-insoluble color material and a hydrophilic color material.
The particle size was a number-converted distribution, with a cumulative 10% particle size (D10) of 18 nm, a cumulative 50% particle size (D50) of 36 nm, and a cumulative 90% particle size (D90) of 42 nm. From the X-ray diffraction spectrum, the average crystallite size was 18 nm.
In addition, the dispersion particle size of the aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (P10) is 25 nm, the cumulative 50% particle size (P50) is 39 nm, and the cumulative 90% particle size (P90) is 43 nm. there were. The viscosity was 4 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 630 nm, indicating a green color.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 20% by weight based on the water-insoluble colorant.

[Example 11] (CI-Pigemnt-Red176 self-dispersed colored fine particle aqueous dispersion)
Next, the hydrophilic color material 1 is changed to the hydrophilic color material 5 and C.I. I. Pigment-Violet 19 is C.I. I. An aqueous dispersion containing 10% of self-dispersing colored fine particles was obtained in the same manner as in Example 1 except that the pigment was changed to Pigment-Red 176. The solid content was taken out from the obtained aqueous dispersion, washed with water, and dried to obtain self-dispersed colored fine particles.
When the infrared absorption spectrum of the self-dispersing colored fine particles was measured, a broad small absorption band group was observed in the range of 3500 to 2300 cm ⁻¹ in addition to the spectrum derived from the water-insoluble colorant, and was identified as a sulfonic acid group. . This sulfonic acid group is derived from the hydrophilic color material 5, and it has been clarified that the self-dispersing colored fine particles are a composite color material of a water-insoluble color material and a hydrophilic color material.
The particle size was a number-converted distribution with a cumulative 10% particle size (D10) of 25 nm, a cumulative 50% particle size (D50) of 38 nm, and a cumulative 90% particle size (D90) of 45 nm. From the X-ray diffraction spectrum, the average crystallite size was 11 nm.
In addition, the dispersed particle size of the aqueous dispersion is a number conversion distribution in which the cumulative 10% particle size (P10) is 28 nm, the cumulative 50% particle size (P50) is 40 nm, and the cumulative 90% particle size (P90) is 44 nm. there were. The viscosity was 7 mPa · s. The surface tension was 62 mN / m. The maximum wavelength of the visible absorption spectrum was 560 nm, indicating a red color.
Furthermore, as a result of analyzing in the same manner as in Example 1, the hydrophilic colorant was 20% by weight based on the water-insoluble colorant.

[Comparative Example 1] (When coloring fine particles are prepared by dissolving and reprecipitating a water-insoluble coloring material without including a hydrophilic coloring material)
<Dissolution reprecipitation step> was performed in the same manner as in Example 1 except that the hydrophilic colorant 1 was not included. In this step, a highly transparent magenta liquid was obtained. Then, the <concentration dialysis step> and the <redispersion step> were performed in the same manner, but no redispersion and precipitation occurred.
The particle size of the coloring material contained in this precipitate is 20 nm for the cumulative 10% particle size (D10), 33 nm for the cumulative 50% particle size (D50), and 36 nm for the cumulative 90% particle size (D90) in terms of number distribution. It was. The average crystallite size was 23 nm. The crystal form was γ type.

[Comparative Example 2] (When colored fine particles are prepared by re-dissolving a water-insoluble color material in water in which a hydrophilic color material is dissolved)
1 part by weight of hydrophilic coloring material 1 was dissolved in 2800 parts by weight of ion-exchanged water, and this was stirred with a stirring blade at 8000 rpm. Next, C.I. I. Pigment-Violet 19, 1 part by weight is dissolved in 280 parts by weight of N-methylpyrrolidone, and this solution is quickly added to the stirring hydrophilic color material aqueous solution through a 0.2 mm needle opening to obtain a highly transparent magenta liquid. Got. And <concentration dialysis process> was performed like Example 1, and <redispersion process> was performed, but it did not redisperse but precipitate was produced.
The particle size of the coloring material contained in the precipitate is 19 nm for the cumulative 10% particle size (D10), 31 nm for the cumulative 50% particle size (D50), and 35 nm for the cumulative 90% particle size (D90) in terms of number distribution. It was. The average crystallite size was 26 nm. The crystal form was γ type.

[Comparative Example 3] (When prepared by dispersing a surfactant in the precipitate obtained in Comparative Example 2)
Add 0.1 part by weight of polyoxyethylene distyrenated phenyl ether to the precipitate obtained in [Comparative Example 2], adjust the total amount to 10 parts by weight with ion-exchanged water, and fill with 0.1 mm zirconia beads. The obtained bead mill was used for dispersion for 6 hours, and a slight amount of ion-exchanged water was added to obtain an aqueous dispersion containing 10% of a coloring material.
The particle size of the coloring material contained in this aqueous dispersion is 19 nm for the cumulative 10% particle size (D10), 31 nm for the cumulative 50% particle size (D50), and 35 nm for the cumulative 90% particle size (D90) in terms of number distribution. Met. In addition, the dispersed particle size was a number-converted distribution with a cumulative 10% particle size (P10) of 112 nm, a cumulative 50% particle size (P50) of 144 nm, and a cumulative 90% particle size (P90) of 219 nm. The viscosity was 12 mPa · s. The surface tension was 42 mN / m. Furthermore, as a result of analyzing in the same manner as in Example 1, the average crystallite size was 26 nm. No hydrophilic coloring material was detected.

[Comparative Example 4] (When the dissolution and reprecipitation step is performed using only the hydrophilic coloring material)
Only the hydrophilic coloring material 1 was dissolved in N-methylpyrrolidone and the <dissolution reprecipitation step> was performed, but the coloring material was dissolved in ion-exchanged water, and fine particles were not recognized. Therefore, this solution was concentrated to obtain a 10% dye solution. The viscosity was 4 mPa · s. The surface tension was 62 mN / m.

[Comparative Example 5] (When dispersed without carrying out complex colored fine particles by dissolution and reprecipitation step)
Hydrophilic coloring material 1, 1 part by weight and C.I. I. Pigment-Violet 19, 1 part by weight in 10 parts by weight of ion-exchanged water, adjusted to pH 8.5 with 1 mol / kg sodium hydroxide, polyoxyethylene distyrenated phenyl ether, 0.2% by weight Further, the total amount was adjusted to 20 parts by weight with ion-exchanged water and dispersed for 6 hours using a bead mill filled with 0.1 mm zirconia beads to obtain an aqueous dispersion containing 10% of a coloring material.
The particle size of the color material contained in this aqueous dispersion is a number conversion distribution, the cumulative 10% particle size (D10) is 83 nm, the cumulative 50% particle size (D50) is 105 nm, and the cumulative 90% particle size (D90). Was 135 nm. In addition, the dispersed particle size was a number-converted distribution with a cumulative 10% particle size (P10) of 93 nm, a cumulative 50% particle size (P50) of 126 nm, and a cumulative 90% particle size (P90) of 185 nm. The viscosity was 12 mPa · s. The surface tension was 42 mN / m.
Furthermore, as a result of analyzing in the same manner as in Example 1, the average crystallite size was 35 nm. The hydrophilic colorant was 33% by weight based on the water-insoluble colorant.

  The production conditions at this time are shown in Table 1, the characteristics of the obtained self-dispersing colored fine particles are shown in Table 2, and the characteristics of the aqueous dispersion are shown in Table 3.

  As shown in Tables 2 and 3, the self-dispersing colored fine particles according to the present invention have a very small particle size and crystallite size, and the aqueous dispersion is very finely dispersed without using a dispersant. It is clear.

[Ink for inkjet recording]
Each raw material was mixed at the following blending ratio, passed through a 0.8 μm Millipore filter to prepare an ink for inkjet recording, and evaluated by the following method.

Aqueous dispersion 50 parts Glycerin 10 parts Diethylene glycol 5 parts Surfynol 465 (manufactured by Air Products) 1 part Ion-exchanged water 34 parts

(1) Dispersed particle size and viscosity The dispersed particle size is measured by a concentrated particle size analyzer FPAR-1000 manufactured by Otsuka Electronics Co., Ltd., and a cumulative 10% particle size (P10), 50% cumulative particle size (P50) of the number conversion distribution, The cumulative 90 particle size (P90) was displayed. The viscosity was measured with an E-type viscometer TV-30 manufactured by Toki Sangyo.

(2) Storage stability The storage stability was left for 3 weeks after the preparation, and the dispersion particle size was measured again in the same manner as described above. ○, those in which a change of 10 to 50% occurred Δ, and those in which a change exceeding 50% occurred were evaluated as ×.

(3) Ink ejectability The ink ejectability was obtained by filling the Epson inkjet printer PX-V600 with the ink for ink jet recording according to the present invention, performing solid printing on Nippon Paper A4PPC paper clean, and not fading more than 50 sheets. ◯, 10 or less and less than 50 sheets faded, Δ or 10 or less.

(4) Plain paper colorability In the same way as described above, the color density of plain paper is the same as described above. The optical density (OD value) of a clean, solidly printed A4PPC paper is X-Rite reflective color spectrocolorimeter X- It was measured by Rite 939, and it was evaluated as ○ when the OD value was 1.10 or more, Δ when it was 0.95 or more and less than 1.10, and × when it was less than 0.95.

(5) Glossy paper glossiness Glossy paper glossiness is the gloss at 20 ° between Epson A4 photographic paper <Glossy> KA420PSK and solid photographic paper parts, as described above. The degree of difference is measured with a digital variable angle photometer UGV-5D manufactured by Suga Test Instruments Co., Ltd., when the difference in gloss is +5 or more, ◯ when the difference in gloss is 0 or more and less than +5, and when the difference in gloss is less than 0 Things were marked as x.

(6) Transparency Transparency is the same as described above, with the haze value when solid printing was performed on an exclusive OHP sheet MJ0PS1N made by Epson, the haze value of the printed part was less than 10 by a Toyo Seiki haze meter, A value of 10 or more and less than 20 was evaluated as Δ, and a value of 20 or more was evaluated as ×.

(7) Light resistance In the same manner as described above, the light resistance was set by printing solid A4 photographic paper <Glossy> KA420PSK manufactured by Epson on the ISUPA UV Tester SUV-W13 manufactured by Iwasaki Electric Co., Ltd., temperature 50 ° C., humidity 60 Irradiating with ultraviolet rays (limited wavelength 295 nm to 450 nm) at an intensity of 100 mW / cm ² , and measuring the OD value before and 50 hours after the ultraviolet irradiation, the residual optical density (OD after 50 hours of ultraviolet irradiation) Value / OD value before ultraviolet irradiation × 100 (%)), the optical density residual ratio is 70% or more, ○ is less than 70%, 30% or more is Δ, and less than 30% is ×.

(8) Water resistance In the same manner as described above, the water resistance was A4PPC paper made by Nippon Paper Industries, which was solid-printed, dipped in water and then watered.

(9) Fixing property Fixing property was evaluated by a peel test using a cellophane tape after solid printing on Epson A4 photographic paper <Glossy> KA420PSK, as described above. The case where there was no detachment ○ and the case where there was detachment were rated as x.

  The evaluation results at this time are shown in Table 4.

  As shown in Table 4, it is clear that the ink for ink jet recording according to the present invention is excellent in various ink characteristics.

[Color filter ink]
The color filter ink according to the present invention was obtained by the same production method and composition as the ink jet recording ink according to the present invention. Although it is clear from Table 4 that these ink characteristics are excellent, R (red), G (green), and B (blue), which are the three primary colors of the color filter, are used for evaluating the performance of the color filter ink. For the ink jet recording inks obtained in Examples 16, 21, and 22 as they were, the color development of the solid printed on Epson dedicated OHP sheet MJ0PS1N in the same manner as described above. Obvious color developability was marked as x) and transparency (transmittance at maximum wavelength was measured using Shimadzu's own spectrophotometer UV-2100, and the transmittance was 50% or more. Less than 50% was evaluated as x.).

  The evaluation results at this time are shown in Table 5.

  As shown in Tables 4 and 5, it is clear that the color filter ink according to the present invention is excellent in various ink characteristics, color developability and transparency.

  The self-dispersing colored fine particles according to the present invention are a composite color material comprising a water-insoluble color material and a hydrophilic color material in which a hydrophilic group is introduced into the color material having the same or similar structure as the water-insoluble color material, It has the function of being dispersed in an aqueous dispersion medium without necessarily using a dispersant, has extremely good dispersion stability at the time of preparing an aqueous dispersion and at the time of ink preparation, has excellent color development and transparency, fixing properties, water resistance Since it is possible to express an image having fastness such as light resistance and light resistance, it is suitable as a colorant that becomes an ink precursor for ink jet recording or color filters.

  Further, the aqueous dispersion according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, so that the dispersion stability at the time of preparing the ink itself and the ink is very good, and the color development and transparency are excellent. In addition, since an image having fastness such as fixability, water resistance, and light resistance can be expressed, it is suitable as a color material dispersion serving as an ink precursor for inkjet recording and color filters.

  Further, the ink for ink jet recording according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, or an aqueous dispersion, so that the dispersion stability is extremely good, and the color developability and transparency are excellent. Since an image having fastness such as fixing property, water resistance and light resistance can be expressed, it is suitable as an ink for ink jet recording.

Further, the color filter ink according to the present invention is composed of self-dispersed colored fine particles having the characteristics as described above, or an aqueous dispersion, so that the dispersion stability is extremely good, and the color developability and transparency are excellent. Since an image having fastness such as fixing property, water resistance and light resistance can be expressed, it is suitable as an ink for a color filter.

Claims (9)

The substance constituting the colored fine particles is hydrophilic to a water-insoluble colorant and a colorant having the same structure as the water-insoluble colorant, or a colorant having the same basic structure or a colorant having the same basic structure but different substituents a composite color materials and the introduction of group hydrophilic colorant, the cumulative 50% particle diameter of the particle size distribution in the number distribution particle size of the composite colorant (D50) is Ru der below 40 nm self-dispersible coloring A method for producing fine particles , a hydrophilic color material preparation step for preparing a hydrophilic color material,
A dissolution reprecipitation step in which the water-insoluble colorant and the hydrophilic colorant are dissolved in an aprotic polar solvent, and charged into an aqueous dispersion medium to obtain a self-dispersed colored fine particle crude;
Concentration dialysis step of concentrating and dialyzing the resulting self-dispersed colored fine particle crude,
A redispersion step in which a dispersion operation is performed by adding an aqueous dispersion medium, a basic substance or an acidic substance to the obtained paste.
A method for producing self-dispersed colored fine particles, characterized in that the obtained aqueous dispersion is filtered, membrane-separated or centrifuged, and is filtered and dried after a post-treatment step for adjusting the concentration. 2. The self-dispersing type according to claim 1, wherein the hydrophilic group of the hydrophilic colorant is one or more functional groups selected from an anionic group, a cationic group, and a nonionic group. A method for producing colored fine particles. The method for producing self-dispersed colored fine particles according to claim 1 or 2, wherein the hydrophilic colorant is contained in an amount of 2 to 100% by weight based on the water-insoluble colorant. 4. The method for producing self-dispersing colored fine particles according to claim 1, wherein the average crystallite size is 25 nm or less. The substance constituting the colored fine particles is a water-insoluble colorant and a colorant having the same structure as the water-insoluble colorant, a colorant having the same basic structure, or a colorant having the same basic structure but different substituents or It is a composite color material with a hydrophilic color material in which a hydrophilic group is introduced into a color material having a similar structure, and the cumulative 50% particle size distribution (P50) of the particle size distribution in the number distribution particle size of the composite color material is 40 nm or less A method for producing an aqueous dispersion in which self-dispersing colored fine particles are dispersed in an aqueous dispersion medium, characterized in that the hydrophilic colorant preparation step for preparing a hydrophilic colorant,
A dissolution reprecipitation step in which the water-insoluble colorant and the hydrophilic colorant are dissolved in an aprotic polar solvent, and charged into an aqueous dispersion medium to obtain a self-dispersed colored fine particle crude;
Concentration dialysis step of concentrating and dialyzing the resulting self-dispersed colored fine particle crude,
A redispersion step in which a dispersion operation is performed by adding an aqueous dispersion medium, a basic substance or an acidic substance to the obtained paste.
A method for producing an aqueous dispersion of self-dispersed colored fine particles, wherein the obtained aqueous dispersion is filtered, membrane-separated or centrifuged to perform a post-treatment step of adjusting the concentration. 6. The method for producing an aqueous dispersion according to claim 5, wherein the cumulative 90% particle size (P90) of the number conversion distribution is 50 nm or less in the dispersed particle size of the aqueous dispersion. Manufacturing method . The method for producing an aqueous dispersion according to claim 5 or 6, wherein in the dispersed particle size of the aqueous dispersion, the cumulative 90% particle size (P90) of the number conversion distribution and the cumulative 50% particle size (P90) of the number conversion distribution ( A method for producing an aqueous dispersion, wherein the particle size ratio (P90 / P50) to P50) is 5 or less. A self-dispersed colored fine particle obtained by the method for producing self-dispersed colored fine particles according to any one of claims 1 to 4 or a water-based dispersion produced by the method according to any one of claims 5 to 7 . An ink for ink jet recording using an aqueous dispersion. A self-dispersed colored fine particle obtained by the method for producing self-dispersed colored fine particles according to any one of claims 1 to 4 or a water-based dispersion produced by the method according to any one of claims 5 to 7 . Color filter ink using aqueous dispersion.