JP2010084037A - Organic pigment composition, colored photosensitive resin composition using the same, and color filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic pigment composition in which organic pigment particulates are contained and the hydrophilicity or hydrophobicity of the particulates or aggregates can be simply switched without passing through a complicated process. <P>SOLUTION: The organic pigment composition contains a crosslinked polymer compound and the organic pigment particulates. The crosslinked polymer compound is a graft type polymer which has a main chain having one or more polymer frameworks selected from the group consisting of polyacrylate, polymethacrylate, polystyrene, polyacrylamide, polymethacrylamide, polyvinylamide, and polyvinyl ether and has a polymer chain having a number average molecular weight of 500 or more as a side chain, and which is crosslinked in the main chain. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an organic pigment composition, a colored photosensitive resin composition and a color filter using the same.

  In recent years, research on nanometer-sized fine particles has been actively conducted. Among such fine particles, fine particles made of organic pigments have come to be used in a wide range of fields. For example, paints, printing inks, electrophotographic toners, inkjet inks, color filter materials, etc. It can be mentioned as its application. Among them, high performance is required, and pigments for inkjet ink and pigments for color filters are particularly important in practical use.

  As a method for producing organic particles, there are a gas phase method, a liquid phase method, a laser ablation method, and the like. Among these, the liquid phase method has attracted attention as a method for producing organic particles having excellent simplicity and productivity.

  Patent Document 1 describes an example in which a pigment particle aqueous dispersion is prepared by a liquid phase method. This method is a method of finally providing as an aqueous dispersion, and a method of providing as an organic solvent dispersion is not mentioned. In addition, this dispersion uses an inkjet ink, and the polymer compound disclosed therein or a crosslinked product thereof imparts dispersibility to the colorant particles exclusively in an aqueous medium. Patent Document 2 describes an example in which pigment particles prepared by a liquid phase method are used and provided as an organic solvent dispersion. However, the organic pigment particles obtained by this method tend to have large primary particle diameters, and have not fully met the demand for fine particles.

  In the preparation of nanoparticles in the liquid phase method, conventionally, a low molecular surfactant or a neutral water-soluble nonionic polymer compound is used in order to prevent aggregation of the nanoparticles. Therefore, even if nanoparticles can be dispersed at a high concentration, it is necessary to use a large amount of dispersing aid, and those technologies can be applied as they are when the viscosity is low and the polymer compound content is extremely low as in the case of inkjet. It is difficult to do.

  Furthermore, in order to meet the requirements for phase conversion to a desired solvent system after preparing nanoparticles in an aqueous medium, an aqueous slurry or aqueous paste containing a high concentration of pigment is prepared, and a resin or resin solution is added and mixed. There is known a flushing method in which the water around the pigment is replaced with a resin or a resin solution by stirring. However, in this method, since the particles are once strongly aggregated in an aqueous medium, the efficiency of coating with the resin is deteriorated and redispersion is difficult (see, for example, Patent Documents 3 and 4).

  As another method, there is also a method of filtering the nanopigment particles once prepared in an aqueous solvent in the state of primary particles or agglomerated in order to prepare an aqueous paste. However, it takes time for filtration, which is industrially inefficient and complicated.

  A low molecular weight anionic or cationic surfactant can also be used as a dispersant, but it is a low molecular weight and dispersion stability may be insufficient. In view of this, attempts have been made to use a cationic polymer compound to phase-convert an aqueous dispersion of particles into an ionic liquid without undergoing a filtration step (see, for example, Non-Patent Document 1). However, the method described here is directed to low concentrations of inorganic particles. There is no mention of organic pigments, and the final dispersion medium may be a non-volatile ionic liquid, and the method described in Non-Patent Document 2 is not suitable for industrial use.

Patent Document 5 discloses a method in which organic nano pigment particles are aggregated in an aqueous medium and an extraction operation is performed in a non-aqueous medium. A method is disclosed in which a membrane filter is used for isolation and then redispersed in a non-aqueous medium in the presence of an organic polymer. However, since the aggregate at the time of isolation is hydrophilic, it takes a long time for filtration.
JP 2004-43776 A JP 2004-123853 A JP-A-5-301037 JP-A-6-161154 JP 2007-262378 A “Small”, 2006, Vol.2, No.7, p.879-883

An object of the present invention is to provide an organic pigment composition that contains organic pigment fine particles and can easily switch between hydrophilicity and hydrophobicity of the fine particles or aggregates without going through complicated steps.
Another object of the present invention is to provide a pigment composition having the above-described properties and exhibiting high contrast when used as a color filter and exhibiting high performance, a colored photosensitive resin composition and a color filter using the same. To do.

The above object has been achieved by the following means.
(1) The number average molecular weight is 500 or more in the main chain having at least one polymer structure selected from the group consisting of polyacrylate, polymethacrylate, polystyrene, polyacrylamide, polymethacrylamide, polyvinylamide, and polyvinyl ether. An organic pigment composition, wherein a graft polymer having a polymer chain as a side chain contains a crosslinked polymer compound bridged in the main chain and organic pigment fine particles.
(2) The organic pigment according to (1), wherein the crosslinked polymer compound has a structure having repeating units (1-1) to (1-3) represented by the following general formula (1): Composition.

_(Wherein, A _1, A 2, _{A 3,} and _{A 4} is .R ₁ to represent each independently a hydrogen atom or a methyl group carboxylic acid, sulfonic acid, phosphoric acid or heterocycle having one or more nitrogen atoms and, (P ₁ represents a polymer chain having a number average molecular weight of 500 or more forming the side chain, and L represents a divalent linking group forming a cross-linked portion.)
(3) The crosslinked polymer compound has a structure having repeating units (2-1) to (2-4) represented by the following general formula (2): (1) or (2) The organic pigment composition described.

(In the formula, A _1-1 , A _1-2 , A ₂ , A ₃ , and A ₄ each independently represent a hydrogen atom or a methyl group. R ₂ represents a heterocyclic group having one or more nitrogen atoms. X represents —O—, —NH—, or —O—Y—NH—CO—Z—, Y represents an alkylene group having 1 to 4 carbon atoms, and Z represents —O— or —NH—. P ₂ represents a polymer chain forming the side chain and having a number average molecular weight of 500 or more, and L represents a divalent linking group forming a cross-linked portion.
(4) The organic pigment composition as described in any one of (1) to (3), wherein the polymer chain having a number average molecular weight of 500 or more is hydrophobic.
(5) The organic pigment composition according to any one of (1) to (4), wherein the crosslinked polymer compound is added to a composition containing the organic pigment fine particles.
(6) The graft polymer constituting the crosslinked polymer compound is (A) a monomer containing at least one of an acidic group and a basic group, (B) a monomer containing a nitrogen-containing heterocycle, (C) non-aqueous Copolymerization of (E) a bifunctional monomer with at least one monomer selected from the group consisting of a monomer having affinity with a medium, and (D) a monomer having affinity with organic pigment fine particles present in an aqueous medium The organic pigment composition according to any one of (1) to (5), which is a coalescence.
(7) The organic pigment composition according to any one of (1) to (6), wherein the organic pigment fine particles have an average primary particle size of 10 to 100 nm.
(8) The organic pigment fine particle composition present as an aqueous aggregate in an aqueous medium is added with the cross-linked polymer compound to form a hydrophobic aggregate (1) to (7) The organic pigment composition according to any one of the above.
(9) Build in which the organic pigment fine particles are formed by mixing a solution of an organic pigment dissolved in a good solvent and a medium that is compatible with the good solvent and that is a poor solvent for the organic pigment. The organic pigment composition according to any one of (1) to (8), wherein the organic pigment composition is an up particulate.
(10) The organic pigment composition as described in (9), which is obtained by containing the hydrophobic aggregate in a non-aqueous medium and deaggregating and redispersing the aggregate.
(11) A colored photosensitive resin composition comprising at least the organic pigment composition according to (10), a binder, a monomer or an oligomer, and a photopolymerization initiator or a photopolymerization initiator system.
(12) A color filter produced using the colored photosensitive resin composition according to (11).

  The organic pigment composition of the present invention contains organic pigment fine particles and a specific cross-linked polymer compound, and according to application or production requirements, the fine particles or aggregates thereof can be easily obtained without complicated steps. It has an excellent effect of being able to switch the phase between the hydrophilicity and the hydrophobicity. In addition, by using the organic pigment composition of the present invention, a colored photosensitive resin composition imparted with desired characteristics can be obtained very efficiently, and the color filter of the present invention using the composition exhibits high contrast and display. High performance can be achieved in devices.

Hereinafter, the organic pigment composition of the present invention will be described.
The organic pigment used in the present invention is preferably one that can form particles by a liquid phase method, and may be used alone, in plural, or in combination.

  The organic pigment is not limited in hue, for example, perylene, perinone, quinacridone, quinacridonequinone, anthraquinone, anthanthrone, benzimidazolone, disazo condensation, disazo, azo, indanthrone, phthalocyanine, triarylcarbonium , Dioxazine, aminoanthraquinone, diketopyrrolopyrrole, thioindigo, isoindoline, isoindolinone, pyranthrone or isoviolanthrone compound pigment, or a mixture thereof.

More specifically, for example, C.I. I. Pigment red 190 (C.I. No. 71140), C.I. I. Pigment red 224 (C.I. No. 71127), C.I. I. Perylene compound pigments such as C.I. Pigment Violet 29 (C.I. No. 71129); I. Pigment orange 43 (C.I. No. 71105), or C.I. I. Perinone compound pigments such as C.I. Pigment Red 194 (C.I. No. 71100); I. Pigment violet 19 (C.I. No. 73900), C.I. I. Pigment violet 42, C.I. I. Pigment red 122 (C.I. No. 73915), C.I. I. Pigment red 192, C.I. I. Pigment red 202 (C.I. No. 73907), C.I. I. Pigment Red 207 (C.I. No. 73900, 73906) or C.I. I. Pigment Red 209 (C.I. No. 73905), a quinacridone compound pigment; I. Pigment red 206 (C.I. No. 73900/73920), C.I. I. Pigment orange 48 (C.I. No. 73900/73920), or C.I. I. Quinacridonequinone compound pigments such as CI Pigment Orange 49 (C.I. No. 73900/73920); I. Anthraquinone compound pigments such as C.I. Pigment Yellow 147 (C.I. No. 60645); I. Anthanthrone compound pigments such as CI Pigment Red 168 (C.I. No. 59300); I. Pigment brown 25 (C.I. No. 12510), C.I. I. Pigment violet 32 (C.I. No. 12517), C.I. I. Pigment yellow 180 (C.I. No. 21290), C.I. I. Pigment yellow 181 (C.I. No. 11777), C.I. I. Pigment orange 62 (C.I. No. 11775), or C.I. I. Benzimidazolone compound pigments such as CI Pigment Red 185 (C.I. No. 12516); I. Pigment yellow 93 (C.I. No. 20710), C.I. I. Pigment yellow 94 (C.I. No. 20038), C.I. I. Pigment yellow 95 (C.I. No. 20034), C.I. I. Pigment yellow 128 (C.I. No. 20037), C.I. I. Pigment yellow 166 (C.I. No. 20035), C.I. I. Pigment orange 34 (C.I. No. 21115), C.I. I. Pigment orange 13 (C.I. No. 21110), C.I. I. Pigment orange 31 (C.I. No. 20050), C.I. I. Pigment red 144 (C.I. No. 20735), C.I. I. Pigment red 166 (C.I. No. 20730), C.I. I. Pigment red 220 (C.I. No. 20055), C.I. I. Pigment red 221 (C.I. No. 20065), C.I. I. Pigment red 242 (C.I. No. 20067), C.I. I. Pigment red 248, C.I. I. Pigment red 262, or C.I. I. Disazo condensed compound pigments such as CI Pigment Brown 23 (C.I. No. 20060); I. Pigment yellow 13 (C.I. No. 21100), C.I. I. Pigment yellow 83 (C.I. No. 21108), or C.I. I. Disazo compound pigments such as CI Pigment Yellow 188 (C.I. No. 21094); I. Pigment red 187 (C.I. No. 12486), C.I. I. Pigment red 170 (C.I. No. 12475), C.I. I. Pigment yellow 74 (C.I. No. 11714), C.I. I. Pigment yellow 150 (C.I. No. 48545), C.I. I. Pigment red 48 (C.I. No. 15865), C.I. I. Pigment red 53 (C.I. No. 15585), C.I. I. Pigment orange 64 (C.I. No. 12760), or C.I. I. Azo compound pigments such as CI Pigment Red 247 (C.I. No. 15915), C.I. I. Indanthrone compound pigments such as C.I. Pigment Blue 60 (C.I. No. 69800); I. Pigment green 7 (C.I. No. 74260), C.I. I. Pigment Green 36 (C.I. No. 74265), Pigment Green 37 (C.I. No. 74255), Pigment Blue 16 (C.I. No. 74100), C.I. I. Phthalocyanine compound pigments such as CI Pigment Blue 75 (C.I. No. 74160: 2) or 15 (C.I. No. 74160); I. Pigment blue 56 (C.I. No. 42800), or C.I. I. Pigment Blue 61 (C.I. No. 42765: 1) and the like triarylcarbonium compound pigments, C.I. I. Pigment violet 23 (C.I. No. 51319) or C.I. I. Pigment Violet 37 (C.I. No. 51345) and other dioxazine compound pigments, C.I. I. Aminoanthraquinone compound pigments such as C.I. Pigment Red 177 (C.I. No. 65300); I. Pigment red 254 (C.I. No. 56110), C.I. I. Pigment Red 255 (C.I. No. 561050), C.I. I. Pigment red 264, C.I. I. Pigment red 272 (C.I. No. 561150), C.I. I. Pigment orange 71, or C.I. I. Diketopyrrolopyrrole compound pigments such as C.I. Pigment Orange 73; I. Thioindigo compound pigments such as C.I. Pigment Red 88 (C.I. No. 7313); I. Pigment yellow 139 (C.I. No. 56298), C.I. I. Pigment Orange 66 (C.I. No. 48210), an isoindoline compound pigment such as C.I. I. Pigment yellow 109 (C.I. No. 56284), or C.I. I. Pigment Orange 61 (C.I. No. 11295) and the like, an inindolinone compound pigment such as C.I. I. Pigment Orange 40 (C.I. No. 59700), or C.I. I. Pigment red 216 (C.I. No. 59710) and the like, or C.I. I. And isoviolanthrone compound pigments such as CI Pigment Violet 31 (C.I. No. 60010). Among these, a quinacridone compound pigment, a diketopyrrolopyrrole compound pigment, a dioxazine compound pigment, a phthalocyanine compound pigment, or an azo compound pigment is preferable, and a diketopyrrolopyrrole compound pigment or a dioxazine compound pigment is more preferable.
In the present invention, two or more kinds of organic pigments or solid solutions of organic pigments can be used in combination.

The organic pigment fine particles in the composition of the present invention include an organic pigment solution obtained by dissolving an organic pigment in a good solvent, a solvent having compatibility with the good solvent and a poor solvent for the organic pigment. Can be produced by mixing.
In the present invention, the organic pigment composition is composed of organic pigment fine particles and a specific crosslinked polymer compound described later (in the present invention, the “crosslinked polymer compound” is a crosslinked polymer compound, and a predetermined polymer is bridged. In addition to the dispersion liquid (hereinafter also referred to as “reprecipitation liquid”) in which the organic pigment fine particles are formed, the organic pigment may be used. It may be a powder composition, an aggregate composition, or a solid composition having fine particles and the specific crosslinked polymer compound. At this time, the organic pigment composition may contain another component other than the organic pigment fine particles and the specific crosslinked polymer compound, and the specific crosslinked polymer compound or the like is independent of the organic pigment fine particles in the composition. Even if they coexist, they may be incorporated in or adsorbed into the organic pigment fine particles. However, in the present invention, it is preferable that the specific crosslinked polymer compound is added after the formation of the organic pigment fine particles, and there is substantially no portion taken into the fine particles obtained in this way, and the surface of the fine particles The crosslinked polymer compound is preferably present in an adsorbed or surrounding state.

  The poor solvent for the organic pigment is not particularly limited as long as it is compatible with or uniformly mixed with a good solvent for dissolving the organic pigment. As a poor solvent for the organic pigment, the solubility of the organic pigment is preferably 0.02% by mass or less, and more preferably 0.01% by mass or less. Although there is no particular lower limit to the solubility of the organic pigment in the poor solvent, 0.000001% by mass or more is practical in consideration of a commonly used organic pigment. This solubility may be the solubility when dissolved in the presence of an acid or alkali. In addition, the compatibility or uniform mixing property of the good solvent and the poor solvent is preferably 30% by mass or more, more preferably 50% by mass or more, with respect to the poor solvent. There is no particular upper limit to the amount of good solvent dissolved in the poor solvent, but it is practical to mix them in an arbitrary ratio.

  The poor solvent is not particularly limited as long as it is compatible with a good solvent as described above and the organic pigment is insoluble or hardly soluble. For example, an aqueous solvent (for example, water, hydrochloric acid, aqueous sodium hydroxide), alcohol Compound solvents, ketone compound solvents, ether compound solvents, aromatic compound solvents, carbon disulfide solvents, aliphatic compound solvents, nitrile compound solvents, halogen compound solvents, ester compound solvents, ionic liquids, mixed solvents thereof and the like An aqueous solvent, an alcohol compound solvent, a ketone compound solvent, an ether compound solvent, an ester compound solvent, or a mixture thereof is preferable, and an aqueous solvent, an alcohol compound solvent, or an ester compound solvent is more preferable.

Examples of the alcohol compound solvent include methanol, ethanol, isopropyl alcohol, n-propyl alcohol, 1-methoxy-2-propanol and the like. Examples of the ketone compound solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Examples of the ether compound solvent include dimethyl ether, diethyl ether, tetrahydrofuran, and the like. Examples of the aromatic compound solvent include benzene and toluene. Examples of the aliphatic compound solvent include hexane. Examples of the nitrile compound solvent include acetonitrile. Examples of the halogen compound solvent include chloroform, dichloromethane, trichloroethylene, iodoform, and the like. Examples of the ester compound solvent include ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, 2- (1-methoxy) propyl acetate and the like. The ionic liquids, for example, 1-butyl-3-methylimidazolium and PF ₆ ^-, etc. and salts thereof.

  The good solvent is not particularly limited as long as it can dissolve the organic pigment to be used and is compatible with or uniformly mixed with the poor solvent. The solubility of the organic pigment in a good solvent is such that the solubility of the organic material is preferably 0.2% by mass or more, and more preferably 0.5% by mass or more. Although there is no particular upper limit to the solubility of the organic pigment in the good solvent, it is practical that it is 50% by mass or less in consideration of a commonly used organic pigment. This solubility may be the solubility when dissolved in the presence of an acid or alkali. The preferred range of the compatibility or uniform mixing property between the poor solvent and the good solvent is as described above.

  Examples of the good solvent include an aqueous solvent (for example, water or hydrochloric acid, an aqueous sodium hydroxide solution), an alcohol compound solvent, an amide compound solvent, a ketone compound solvent, an ether compound solvent, an aromatic compound solvent, a carbon disulfide solvent, and a fat. Group compound solvents, nitrile compound solvents, sulfoxide compound solvents, halogen compound solvents, ester compound solvents, ionic liquids, carboxylic acid compounds, sulfonic acid compounds, sulfuric acid, mixed solvents thereof, aqueous solvents, alcohol compound solvents, Ketone compound solvents, ether compound solvents, sulfoxide compound solvents, ester compound solvents, amide compound solvents, carboxylic acid compounds, sulfonic acid compounds, sulfuric acid, or mixtures thereof are preferred, aqueous solvents, alcohol compound solvents, ester compound solvents, sulfoxide compounds. solvent Amide compound solvent, a carboxylic acid compound, sulfonic acid compound, more preferably sulfuric acid, the sulfoxide compound solvent, the amide compound solvent, a carboxylic acid compound, sulfonic acid compound, is particularly preferred sulfate.

Examples of the alcohol compound solvent include methanol, ethanol, isopropanol, n-propanol, 1-methoxy-2-propanol, and the like. Examples of the ketone compound solvent include acetone, methyl ethyl ketone, and cyclohexanone. Examples of the ether compound solvent include dimethyl ether, diethyl ether, tetrahydrofuran, and the like. Examples of the aromatic compound solvent include nitrobenzene, chlorobenzene, and dichlorobenzene. Examples of the aliphatic compound solvent include hexane. Examples of the nitrile compound solvent include acetonitrile. Examples of the sulfoxide compound solvent include dimethyl sulfoxide, diethyl sulfoxide, hexamethylene sulfoxide, sulfolane and the like. Examples of the halogen compound solvent include chloroform, dichloromethane, trichloroethylene, iodoform, and the like. Examples of the ester compound solvent include ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, 2- (1-methoxy) propyl acetate and the like. The ionic liquids, for example, 1-butyl-3-methylimidazolium and PF ₆ ^-, etc. and salts thereof. Examples of the amide compound solvent include N, N-dimethylformamide, 1-methyl-2-pyrrolidone, 2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 2-pyrrolidinone, ε-caprolactam, formamide, N -Methylformamide, acetamide, N-methylacetamide, N, N-dimethylacetamide, N-methylpropanamide, hexamethylphosphoric triamide and the like. Examples of the carboxylic acid compound include formic acid, acetic acid, chloroacetic acid, dichloroacetic acid, oxalic acid, trifluoroacetic acid, trichloroacetic acid, 2,2-dichloropropionic acid, squaric acid, and the like. Examples of the sulfonic acid compound include methanesulfonic acid, p-toluenesulfonic acid, sulfuric acid, chlorosulfonic acid, trifluoromethanesulfonic acid, and the like.

  There are some common examples of those listed as specific examples of good solvents and those listed as poor solvents, but the same solvents are not combined as good solvents and poor solvents. It is sufficient that the solubility in is sufficiently higher than the solubility in a poor solvent. For example, the solubility difference is preferably 0.2% by mass or more, and more preferably 0.5% by mass or more. Although there is no particular upper limit to the difference in solubility between the good solvent and the poor solvent, it is practical that the difference is 50% by mass or less in consideration of a commonly used organic pigment.

  In addition, the concentration of the organic pigment solution in which the organic pigment is dissolved in the good solvent is preferably a saturated concentration of the organic pigment with respect to the good solvent under the dissolution conditions or a range of about 1/100 of this.

  There are no particular limitations on the conditions for preparing the organic pigment solution, and a range from normal pressure to subcritical and supercritical conditions can be selected. The temperature at normal pressure is preferably −10 to 150 ° C., more preferably −5 to 130 ° C., and particularly preferably 0 to 100 ° C.

  In the present invention, the organic pigment is also preferably dissolved in an acidic or alkaline manner. In general, in the case of a pigment having an alkaline and dissociable group in the molecule, alkali is used, and when there is no alkaline and dissociable group and there are many nitrogen atoms in the molecule that are prone to add protons, acidity is used. For example, quinacridone, diketopyrrolopyrrole, disazo condensation compound pigments are alkaline, and phthalocyanine compound pigments are acidic.

  Bases used for alkaline dissolution are inorganic bases such as lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, or barium hydroxide, or trialkylamine, diazabicycloundecene (DBU), An organic base such as a metal alkoxide is preferable, but an inorganic base is preferable.

  The amount of the base used is an amount capable of uniformly dissolving the pigment, and is not particularly limited. However, in the case of an inorganic base, it is preferably 1.0 to 30 molar equivalents relative to the organic material, more preferably 1 0.0 to 25 molar equivalents, more preferably 1.0 to 20 molar equivalents. In the case of an organic base, it is preferably 1.0 to 100 molar equivalents, more preferably 5.0 to 100 molar equivalents, still more preferably 20 to 100 molar equivalents relative to the organic material.

  The acid used for the acidic dissolution is preferably an inorganic acid such as sulfuric acid, hydrochloric acid, or phosphoric acid, or an organic acid such as acetic acid, trifluoroacetic acid, oxalic acid, methanesulfonic acid, or trifluoromethanesulfonic acid. It is an inorganic acid. Particularly preferred is sulfuric acid.

  The amount of the acid used is an amount capable of uniformly dissolving the organic pigment, and is not particularly limited, but is often used in an excessive amount as compared with the base. Regardless of inorganic acid or organic acid, it is preferably 3 to 500 molar equivalents, more preferably 10 to 500 molar equivalents, still more preferably 30 to 200 molar equivalents relative to the organic material.

  When mixing alkali or acid with an organic solvent and using it as a good solvent for organic pigments, a solvent having high solubility in some alkali or acid such as water or lower alcohol in order to completely dissolve the alkali or acid Can be added to the organic solvent. The amount of water or lower alcohol is preferably 50% by mass or less, more preferably 30% by mass or less, based on the total amount of the organic material solution. Specifically, water, methanol, ethanol, n-propanol, isopropanol, butyl alcohol, or the like can be used.

  There is no particular limitation on the conditions of the poor solvent when the organic particles are produced, that is, when the organic particles are deposited and formed, and a range from normal pressure to subcritical and supercritical conditions can be selected. The temperature at normal pressure is preferably −30 to 100 ° C., more preferably −10 to 60 ° C., and particularly preferably 0 to 30 ° C.

  When mixing the organic pigment solution and the poor solvent, either of them may be added and mixed. However, the organic pigment solution is preferably added to the poor solvent and mixed, and the poor solvent is stirred at that time. It is preferable that the The stirring speed is preferably 100 to 10,000 rpm, more preferably 150 to 8000 rpm, and particularly preferably 200 to 6000 rpm. A pump or the like may be used for the addition, or it may not be used. Moreover, although addition in a liquid or addition outside a liquid may be sufficient, addition in a liquid is more preferable. The mixing ratio of the organic pigment solution and the poor solvent (ratio of good solvent / poor solvent in the organic pigment fine particle reprecipitation liquid) is preferably 1/50 to 2/3 in volume ratio, more preferably 1/40 to 1/2, 1/20 to 3/8 is particularly preferable. As an aqueous medium, said aqueous solvent contains at least 60 mass%, Preferably it contains 80 mass% or more.

  When the organic pigment composition is, for example, a dispersion such as the reprecipitation liquid, the organic pigment fine particle content is not particularly limited, but the organic pigment fine particle content is in the range of 10 to 40,000 mg per 1000 ml of the medium. Is preferable, more preferably in the range of 20 to 30000 mg, and particularly preferably in the range of 50 to 25000 mg.

  Moreover, the preparation scale at the time of producing | generating organic pigment microparticles | fine-particles is although it does not specifically limit, It is preferable that the mixing amount of a poor solvent is 1-1000L, and it is more preferable that it is a 1-100L preparation scale.

  Regarding the particle size of organic pigment fine particles, there is a method of expressing the average size of the population by quantifying by a measurement method, but as a common use, the mode diameter indicating the maximum value of the distribution, the center of the integral distribution curve There are median diameters corresponding to the values, various average diameters (number average, length average, area average, mass average, volume average, etc.), etc. In the present invention, unless otherwise specified, the average particle diameter is a number. Mean diameter. The average particle diameter of the organic pigment fine particles (primary particles) is a nanometer size, more preferably 1 to 200 nm, still more preferably 10 to 100 nm, and particularly preferably 10 to 80 nm. The particles formed in the present invention may be crystalline particles, amorphous particles, or a mixture thereof.

  In the present invention, the ratio (Mv / Mn) of the volume average particle diameter (Mv) and the number average particle diameter (Mn) is used as an index representing the monodispersity of the particles unless otherwise specified. The monodispersity of particles (primary particles) contained in the dispersion used in the method for concentrating organic pigment fine particles, that is, Mv / Mn, is preferably 1.0 to 2.0, and preferably 1.0 to 1.8. Is more preferable, and 1.0 to 1.5 is particularly preferable.

  Examples of the method for measuring the particle size of the organic pigment fine particles include a microscope method, a weight method, a light scattering method, a light blocking method, an electric resistance method, an acoustic method, and a dynamic light scattering method. Is particularly preferred. Examples of the microscope used for the microscopy include a scanning electron microscope and a transmission electron microscope. Examples of the particle measuring apparatus based on the dynamic light scattering method include Nanotrack UPA-EX150 manufactured by Nikkiso Co., Ltd., Dynamic Light Scattering Photometer DLS-7000 series manufactured by Otsuka Electronics Co., Ltd., and LB-400 manufactured by Horiba, Ltd. Product name).

In the present invention, when preparing a dispersion by depositing organic pigment fine particles, at least one of the organic pigment solution and the poor solvent may contain a dispersant. At this time, at least the organic pigment solution contains a dispersant (in the present invention, a dispersant added at the time of particle precipitation is simply referred to as a “dispersant” and may be distinguished from a hydrophobizing dispersant described later). It is preferable to make it.
Examples of dispersants that can be used include anionic, cationic, amphoteric, nonionic, or pigment derivative polymers or low molecular weight dispersants (hereinafter referred to as “high molecular weight and low molecular weight” Molecular dispersing agent "or" low molecular dispersing agent "). The addition amount of the polymer or low molecular dispersant is preferably 1% by mass or more and 1000% by mass or less, more preferably 5% by mass or more and 200% by mass or less, more preferably 10% by mass or more and 100% by mass with respect to the dissolved pigment. % Or less is particularly preferable. If it is less than 10% by mass, the effect of suppressing the growth and aggregation of the pigment particles is reduced, and if it exceeds 1000% by mass, problems such as increased viscosity and poor dissolution tend to occur.

Hereinafter, the polymer dispersant will be described.
The molecular weight of the polymer dispersant is preferably 1,000 or more and 200,000 or less in terms of number average molecular weight, more preferably 2,000 or more and 100,000 or less, and particularly preferably 3,000 or more and 50,000 or less. If it is less than 1,000, the effect of suppressing the growth and strong aggregation of pigment particles is reduced, and if it exceeds 200,000, problems such as increased viscosity and poor dissolution tend to occur. The polymer in the present invention refers to a polymer having a number average molecular weight of 1000 or more.

  The polymer dispersant is nonionic, specifically, polyvinylpyrrolidone, polyvinyl alcohol, polyvinyl methyl ether, polyethylene glycol, polypropylene glycol, polyacrylamide, polydimethylaminopropyl acrylamide, vinyl alcohol-vinyl acetate copolymer. Polymer, polyvinyl alcohol-partial formalized product, polyvinyl alcohol-partial butyralized product, vinylpyrrolidone-vinyl acetate copolymer, vinylpyrrolidone-dimethylaminopropylacrylamide, vinylpyrrolidone-vinylpyridine copolymer, vinylpyrrolidone-vinylimidazole copolymer Polymer, polyethylene oxide / propylene oxide block copolymer, polyethylene oxide / propylene oxide random copolymer, etc. Among them, polyvinylpyrrolidone, polydimethylaminopropylacrylamide, vinylpyrrolidone-dimethylaminopropylacrylamide, vinylpyrrolidone-vinylpyridine copolymer, vinylpyrrolidone-vinylimidazole copolymer, polyethylene oxide / propylene oxide block copolymer, A polyethylene oxide / propylene oxide random copolymer is preferred.

Examples of anionic substances include polyacrylates, polyvinyl sulfates, polybenzene sulfonates, condensed naphthalene sulfonates, cellulose derivatives, and starch derivatives. Among these, polybenzene sulfonate and condensed naphthalene sulfonate are more preferable.
These anionic ones can be obtained by copolymerizing an anionic monomer, but they may be copolymerized with not only the anionic monomer itself but also a nonionic monomer. Specific examples of the nonionic monomer include vinyl pyrrolidone, styrene, naphthalene, styryl methyl chloride, vinyl imidazole, vinyl pyridine, acrylamide, vinyl amide, dimethylaminopropyl acrylamide, and the like.

  As the cationic compound, a polymer compound having a quaternary ammonium moiety is particularly preferable. Poly (methacryloxyalkylammonium salt), poly (methacryloxyarylammonium salt), poly (acryloxyalkylammonium salt), poly (acrylic) Oxyarylammonium salts), poly (diallylammonium salts), polystyrylmethyleneimidazolium salts, polystyrylmethylenepyridinium salts, and the like. In addition, natural polymers such as alginate, gelatin, albumin, casein, gum arabic, tragacanth gum, and lignin sulfonate can also be used.

  As the amphoteric one, copolymers of those mentioned above as anionic and cationic are preferable.

  These polymer dispersants can be used singly or in combination of two or more. The dispersant used for dispersing the pigment is described in detail on pages 29 to 46 of “Pigment dispersion stabilization and surface treatment technology / evaluation” (Chemical Information Association, issued in December 2001).

Hereinafter, the low molecular dispersant will be described.
As low molecular weight dispersants, anionic ones include N-acyl-N-alkyl taurine salts, fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, dialkyl sulfosuccinates, alkyl phosphates. Examples include ester salts, naphthalene sulfonic acid formalin condensates, polyoxyethylene alkyl sulfate esters, and the like. Of these, N-acyl-N-alkyltaurine salts are preferred. As the N-acyl-N-alkyltaurine salt, those described in JP-A-3-273067 are preferable. These anionic dispersants can be used alone or in combination of two or more.

  Cationic ones include quaternary ammonium salts, alkoxylated polyamines, aliphatic amine polyglycol ethers, aliphatic amines, diamines and polyamines derived from aliphatic amines and alcohols, imidazolines derived from fatty acids and these And salts of cationic substances. These cationic dispersants can be used alone or in combination of two or more.

The amphoteric one is a dispersant having both an anionic group part in the molecule of the anionic dispersant and a cationic group part in the molecule of the cationic dispersant.
Nonionic ones include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, etc. Can do. Among these, polyoxyethylene alkyl aryl ether is preferable. These nonionic dispersants can be used alone or in combination of two or more.

  The pigment derivative type is derived from an organic pigment as a parent substance and is obtained by a pigmentation reaction of a pigment derivative type dispersant produced by chemically modifying the parent structure or a chemically modified pigment precursor. Defined as a pigment derivative type dispersant. For example, a sugar-containing pigment derivative-type dispersant, a piperidyl-containing pigment derivative-type dispersant, a naphthalene or perylene-derived pigment derivative-type dispersant, a pigment derivative-type dispersant having a functional group linked to a pigment parent structure via a methylene group, Pigment parent structure chemically modified with polymer, pigment derivative type dispersant having sulfonic acid group, pigment derivative type dispersant having sulfonamide group, pigment derivative type dispersant having ether group, carboxylic acid group, carboxylic acid ester And pigment derivative type dispersants having a group or a carboxamide group.

  In the present invention, when preparing an organic pigment solution dissolved in a good solvent, it is also preferable that a pigment dispersant containing an amino group is allowed to coexist. Here, the amino group includes a primary amino group, a secondary amino group, and a tertiary amino group, and the number of amino groups may be one or more. A pigment derivative compound in which a substituent having an amino group is introduced into the pigment skeleton, or a polymer compound having a monomer having an amino group as a polymerization component may be used. Examples thereof include, for example, compounds described in JP-A Nos. 2000-239554, 2003-96329, 2001-31885, JP-A-10-339949, and JP-B-5-72943. However, it is not limited to these.

In the present invention, an acid can be added to prepare an aqueous aggregate after preparation of a reprecipitation liquid (aqueous dispersion) of organic pigment fine particles. Alternatively, in preparing an aqueous dispersion by precipitating organic pigment fine particles, an acid may be added to a poor solvent, and the organic pigment fine particles may be made into a hydrophilic aggregate by adding a pigment solution thereto. In particular, it is preferable to obtain an aqueous aggregate by adding an acid to a poor solvent. Here, the “aqueous aggregate” in the present invention refers to an aggregate in a state where the surface of the aggregate or organic pigment fine particles constituting the aggregate is coated with a hydrophilic dispersant. Here, when quantitatively distinguishing between hydrophilicity and hydrophobicity, the theoretical formula of the solubility parameter (SP value) proposed by Toshinao Okitsu (Journal of the Adhesion Society of Japan Vol. 29, No. 6 (1993) 249-259) term) with, when the value calculated for the dispersant is 20 MPa ^1/2 or more, that the dispersant is hydrophilic. The hydrophilic aggregate is not particularly limited as long as two or more primary particles of the organic pigment fine particles are aggregated, but usually has an average particle diameter of about 5 μm, preferably 0.04 to 10 μm.
The acid used for forming the aqueous aggregate is preferably acetic acid, hydrochloric acid, sulfuric acid or formic acid, more preferably acetic acid or hydrochloric acid. The pH of the aqueous dispersion during formation of the aqueous aggregate is not particularly limited as long as the aggregate is formed, but is preferably pH 1 to 6, more preferably pH 2 to 4. In the aqueous aggregate, it is practical that the solid content is almost composed of pigment, but the content of the pigment in the liquid after preparation is practically 0.004 to 4% by mass, for example. is there. This concentration is the same for the non-aqueous aggregate described later.

In the present invention, it is preferable that an organic polymer compound having a mass average molecular weight of 1000 or more coexists with the aqueous aggregate to form a hydrophobic aggregate. (Hereinafter, “an organic polymer compound having a mass average molecular weight of 1000 or more” may be referred to as an “organic polymer compound” or a “hydrophobizing dispersant”.)
In the present invention, after forming a hydrophobic aggregate by adding at least one organic polymer compound having a mass average molecular weight of 1000 or more to organic pigment fine particles present in an aqueous medium, Aggregates can be isolated. Even if the organic nanoparticles present in the aqueous medium are filtered with a filter paper as they are, even if they are passed through the filter paper or filtered with a filter, it takes an enormous amount of time. As described above, by adding an acid or an alkali to a poor solvent, the organic pigment fine particles can be obtained as an aqueous aggregate when preparing an aqueous dispersion of organic pigment fine particles. However, if it is only this, since the aggregate is hydrophilic, it does not become a large aggregate in an aqueous medium, and the dehydrating property is poor, so even if this is filtered, it takes a long time to filter. . Therefore, in the present invention, it is preferable to add the organic polymer compound to make the aqueous aggregate into a non-hydrophilic aggregate (hereinafter sometimes referred to as “hydrophobic aggregate”). By adding the organic polymer compound, the organic pigment fine particles can be made larger aggregates in the aqueous medium. According to this method, the time required for filtration is shortened, and the filterability can be greatly improved. In the present invention, the “hydrophobic aggregate” refers to an aggregate in a state where the surface of the aggregate or the organic pigment fine particles constituting the aggregate is coated with a hydrophobizing dispersant. Here, when quantifying the hydrophilicity / hydrophobicity, the theoretical formula of the solubility parameter (SP value) proposed by Toshinao Okitsu (Journal of the Adhesion Society of Japan Vol. 29, No. 6 (1993) 249-259) When the value calculated for the dispersant is less than 20 MPa ^1/2 , the dispersant is referred to as a hydrophobizing dispersant.
In the present invention, the organic polymer compound is preferably added to the aqueous dispersion containing the hydrophilic aggregate.

  As a hydrophobic aggregate, it is preferable that an average particle diameter is 10 micrometers or more, and the larger one is more preferable. If it is less than 10 μm, it takes a lot of time to isolate the aggregate, and even if it is tried to filter, it will pass through the filter paper or filter or be clogged. The average particle diameter referred to here is the diameter of an aggregate obtained by observing the aggregate with an optical microscope and measuring separately observed mono-sashi. The diameter here refers to measuring the length of the aggregate from end to end and defining the longest length as the diameter. Aggregates in the present invention are those in which two or more primary particles are gathered and grown to form secondary particles, which are aggregates in the form of powder or paste even if they are present in the liquid as sediment. Alternatively, it may be a secondary particle dispersion in which secondary particles are dispersed and exist in the medium.

  The pigment composition of the present invention (in the present invention, the term “composition” refers to a group in which two or more components are not extremely unevenly distributed and exist substantially homogeneously as a whole. It may be in the form of a paste, and if the above conditions are satisfied, it means that the above-mentioned aggregates are included.) The specific cross-linked polymer compound to be contained in polyacrylate, polymethacrylate, polystyrene, polyacrylamide, poly It has one or more polymer structure parts selected from a bridge made of methacrylamide, polyvinylamide, and polyvinyl ether (in the present invention, when it has a polymer structure part or polymer skeleton of a predetermined polymer, it is an object. This means that the polymer compound has the same molecular structure as that of the predetermined polymer in at least a part of the polymer compound, There may be any number of parts having the same molecular structure as the mer, and there may be any substituents and side chains in this part.) A polymer chain having a number average molecular weight of 500 or more in the main chain as a side chain The graft type polymer has a crosslinked compound bridged in the main chain.

  The crosslinked polymer compound preferably has a structure having repeating units (1-1) to (1-3) represented by the following general formula (1).

式中、Ａ_１、Ａ_２、Ａ_２、及びＡ_４はそれぞれ独立に水素原子またはメチル基を表す。Ｒ_１はカルボン酸、スルホン酸、リン酸、または窒素原子を１つ以上有するヘテロ環基を表す。Ｐ_１は前記側鎖をなす数平均分子量５００以上の高分子鎖を表す。Ｌは架橋部をなす２価の連結基を表す。ここで繰り返し単位（１−３）について補足すると、置換基Ａ_３側のユニットと置換基Ａ_４側のユニットとが連結基Ｌにより架橋連結されたことを意味している。すなわち換言すれば、上記一般式（１）で表される架橋高分子化合物の構造は、繰り返し単位（１−１），（１−２），及び（１−３）の上記置換基Ａ_３側のユニットを有するグラフト型ポリマーと、繰り返し単位（１−１），（１−２），及び（１−３）の上記置換基Ａ_４側のユニットを有する別のグラフト型ポリマーとが連結基Ｌで架橋連結された構造ということができる。このとき、１つのグラフト型ポリマーに連結基Ｌが多数含まれ多くの箇所で架橋連結されていたり、３つ以上のグラフト型ポリマーが架橋連結されていたりしてもよいことは言うまでもない。
本発明においては、上記架橋高分子化合物が、多数のグラフト型ポリマーからなり、互いに多数の連結位置で架橋連結された網目状の架橋高分子化合物であることが好ましい。

In the formula, A ₁ , A ₂ , A ₂ , and A ₄ each independently represent a hydrogen atom or a methyl group. R ₁ represents carboxylic acid, sulfonic acid, phosphoric acid, or a heterocyclic group having one or more nitrogen atoms. P ₁ represents a polymer chain having a number average molecular weight of 500 or more forming the side chain. L represents a divalent linking group that forms a cross-linked portion. Here, supplementing the repeating unit (1-3) means that the unit on the substituent A ₃ side and the unit on the substituent A ₄ side are cross-linked by a linking group L. In other words, the structure of the crosslinked polymer compound represented by the above general formula (1) are repeating units (1-1), (1-2), and the substituent _{A 3} side (1-3) graft polymer and a repeating unit having the unit (1-1), (1-2), and another graft polymer and the linking group L having a unit of the above substituents _{a 4} side (1-3) It can be said that the structure is cross-linked by. At this time, it goes without saying that one graft-type polymer may contain many linking groups L and may be cross-linked at many locations, or three or more graft-type polymers may be cross-linked.
In the present invention, the cross-linked polymer compound is preferably a network-like cross-linked polymer compound composed of a large number of graft polymers and cross-linked at a large number of positions.

  Furthermore, it is particularly preferable that the polymer compound has a structure having a repeating unit represented by the following general formula (2).

式中、Ａ_１-１、Ａ_１-２、Ａ_２、及びＡ_３はそれぞれ独立に水素原子またはメチル基を表す。Ｒ_２は窒素原子を１つ以上有するヘテロ環基を表す。Ｘは−Ｏ−、−ＮＨ−、または−Ｏ−Ｙ−ＮＨ−ＣＯ−Ｚ−を表し、Ｙは炭素数１〜４のアルキレン基を表し、Ｚは−Ｏ−または−ＮＨ−を表す。Ｐ_２は前記側鎖をなす数平均分子量５００以上の高分子鎖を表す。Ｌは前記橋架けをなす２価の連結基を表す。繰り返し単位（２−４）については、上記繰り返し単位（１−３）と同様である。

In the formula, A _1-1 , A _1-2 , A ₂ , and A ₃ each independently represent a hydrogen atom or a methyl group. R ₂ represents a heterocyclic group having one or more nitrogen atoms. X represents —O—, —NH—, or —O—Y—NH—CO—Z—, Y represents an alkylene group having 1 to 4 carbon atoms, and Z represents —O— or —NH—. P ₂ represents a number-average molecular weight of 500 or more polymeric chains forming the side chain. L represents a divalent linking group that forms the bridge. The repeating unit (2-4) is the same as the above repeating unit (1-3).

  Further, the polymer chain having a number average molecular weight of 500 or more in the crosslinked polymer compound is preferably hydrophobic, the polymer chain having a number average molecular weight of 500 or more has an affinity for a non-aqueous medium, and the non-aqueous medium Among them, it is more preferable to have an action of dispersing the organic pigment fine particles, and it is particularly preferable that the crosslinked polymer compound also has a structural portion having an affinity for the organic pigment fine particles.

  The crosslinked polymer compound acts on the hydrophilic aggregate, and the structural portion having an affinity for the organic pigment fine particles covers the surface of the aqueous aggregate or the organic pigment fine particles constituting the aggregate. Aggregates or the particles can be hydrophobized by structural sites that have an affinity for non-aqueous media. Despite having a cross-linked structure, each polymer has a graft chain and the polymer chains are close to each other, so that the apparent molecular weight is lowered and compact. Therefore, it is presumed that it easily penetrates into the gaps between the hydrophilic aggregates and easily covers the surface of the organic pigment fine particles.

  The specific crosslinked polymer compound in the present invention is preferably adsorbed on the aggregated organic pigment fine particles. At this time, since the polymer compound has a cross-linked structure, its adsorption becomes strong and it is difficult to desorb from the organic pigment fine particles. For this reason, since the organic polymer compound can act as a dispersant as it is in a non-aqueous medium even after passing through steps such as filtration, washing, and redispersion, it is not necessary to add a considerable amount of a dispersant. . In order to adjust the dispersibility, a dispersant may be newly added later, but it is preferable not to add it from the viewpoint of production cost.

  Furthermore, since the organic pigment fine particles constituting the aggregate in the present invention are preferably aggregated in a state of being coated with a crosslinked polymer compound, when aggregated without such a crosslinked polymer compound, for example, hydrochloric acid or the like Compared with the case of agglomeration, the subsequent re-dispersion is easy, the organic pigment fine particles are easily loosened to the primary particles, and the contrast becomes high.

  The crosslinked polymer compound may be added as it is, but it is preferable to add it after dissolving it in a solvent from the viewpoint of obtaining good filterability. As the solvent for dissolution, it is miscible with the organic pigment fine particle aqueous dispersion and can dissolve the crosslinked polymer compound. Further, even if the crosslinked polymer compound does not precipitate by itself after addition, There is no particular limitation.

  Examples of the solvent for dissolving the crosslinked polymer compound include an aqueous solvent (for example, water or hydrochloric acid, an aqueous sodium hydroxide solution), an alcohol compound solvent, an amide compound solvent, a ketone compound solvent, an ether compound solvent, an aromatic compound solvent, two Examples thereof include carbon sulfide solvents, aliphatic compound solvents, nitrile compound solvents, sulfoxide compound solvents, halogen compound solvents, ester compound solvents, ionic liquids, mixed solvents thereof, aqueous solvents, alcohol compound solvents, ketone compound solvents, ethers. A compound solvent, a sulfoxide compound solvent, an ester compound solvent, an amide compound solvent, a nitrile compound solvent, or a mixture thereof is preferable, and a ketone compound solvent, an ether compound solvent, a nitrile compound solvent, or a mixture thereof is particularly preferable.

Examples of the alcohol compound solvent include methanol, ethanol, isopropyl alcohol, n-propyl alcohol, 1-methoxy-2-propanol and the like. Examples of the ketone compound solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. Examples of the ether compound solvent include dimethyl ether, diethyl ether, tetrahydrofuran, and the like. Examples of the aromatic compound solvent include benzene and toluene. Examples of the aliphatic compound solvent include hexane. Examples of the nitrile compound solvent include acetonitrile. Examples of the halogen compound solvent include dichloromethane and trichloroethylene. Examples of the ester compound solvent include ethyl acetate, ethyl lactate, 2- (1-methoxy) propyl acetate and the like. The ionic liquids, for example, 1-butyl-3-methylimidazolium and PF ₆ ^-, etc. and salts thereof.

  The amount of the solvent for dissolving the crosslinked polymer compound is not particularly limited as long as the crosslinked polymer compound can be dissolved and a hydrophobic aggregate that can be easily filtered can be formed. However, the production complexity and the raw material cost are reduced. In consideration of further reduction, the amount is preferably as small as possible. In terms of mass ratio, when the organic pigment fine particle aqueous dispersion is 100, the added solvent is preferably in the range of 0 to 100, more preferably in the range of 0 to 70. If too much, filtration may take a long time.

  After adding the cross-linked polymer compound, stirring is preferably performed so as to sufficiently mix with the organic pigment fine particle aqueous dispersion. A normal method can be used for stirring and mixing. Although there is no restriction | limiting in particular in the temperature when adding and mixing this organic polymer compound, it is preferable that it is 1-100 degreeC, and it is more preferable that it is 5-60 degreeC. The addition and mixing of the crosslinked polymer compound may be carried out using any apparatus as long as each step can be preferably carried out. For example, an apparatus such as a stirring blade or a ramond stirrer can be used.

  The addition amount of the crosslinked polymer compound is preferably 1% by mass or more and 1000% by mass or less, more preferably 10% by mass or more and 200% by mass or less, and more preferably 20% by mass or more and 100% by mass or less with respect to the pigment. If the amount is less than 1% by mass, the effect of making the nanoparticles hydrophobic (non-aqueous) is reduced. If the amount exceeds 1000% by mass, problems such as an increase in viscosity during redispersion tend to occur. In the present invention, the mass average molecular weight of the crosslinked polymer compound is preferably 1000 or more. Although there is no particular upper limit, it is more preferably 3000,000 or less, more preferably 3000 or more and 300,000 or less, and particularly preferably 5000 or more and 100,000 or less.

  In the present invention, the term “molecular weight” simply means a mass average molecular weight, and the mass average molecular weight is an average molecular weight in terms of polystyrene measured by gel permeation chromatography (carrier: tetrahydrofuran) unless otherwise specified.

  Examples of the graft-type polymer that forms a crosslinked polymer compound that can be used in the present invention include “Disperbyk-110 (a copolymer containing an acid group), 130 (polyamide), 161, 162, 163, 164, 165, manufactured by BYK Chemie. 166, 170 (polymer copolymer) ”,“ BYK-P104, P105 (high molecular weight unsaturated polycarboxylic acid) ”,“ EFKA 4047, 4050, 4010, 4165 (polyurethane type), EFKA 4330, 4340 (both blocks) manufactured by EFKA. Polymer), 4400, 4402 (modified polyacrylate), 5010 (polyesteramide), 5765 (high molecular weight polycarboxylate), 6220 (fatty acid polyester) ”,“ Ajisper PB821, PB822 ”manufactured by Ajinomoto Fan Techno Co., Kyoeisha Chemical Co., Ltd. "Floren T" -710 (urethane oligomer) "," Polyflow No. 50E, No. 300 (acrylic copolymer) "," Disparon KS-860, 873SN, 874, # 2150 (aliphatic polyvalent carboxylic acid) manufactured by Enomoto Kasei Co., Ltd. , # 7004 (polyetherester), DA-703-50, DA-705, DA-725 "," Demol RN, N (Naphthalenesulfonic acid formalin polycondensate), MS, C, SN-B (manufactured by Kao) Aromatic sulfonic acid formalin polycondensate) ”,“ homogenol L-18 (polymeric polycarboxylic acid) ”,“ Emulgen 920, 930, 935, 985 (polyoxyethylene nonylphenyl ether) ”,“ acetamine 86 (stearylamine) Acetate) ", Lubrizol" Solsperse 55000 (graft type polymer), 1 3240 (polyesteramine), 3000, 17000, 27000 (polymer having a functional part at the end), 24000, 28000, 32000, 38500 (graft type polymer) ", Nikko Chemical's" Nikkor T106 (polyoxyethylene sorbitan) " Monooleate), MYS-IEX (polyoxyethylene monostearate) ”or the like (both are trade names).

  The crosslinked polymer compound in the present invention may be used alone or in combination of two or more. Moreover, a crosslinked polymer compound may be used independently and may be used 2 or more types.

Furthermore, the graft polymer forming the crosslinked polymer compound is preferably a polymer compound obtained by copolymerization using at least one of the following monomers (A) to (E).
(A) Monomer containing at least one of acidic group and basic group (B) Monomer containing nitrogen-containing heterocycle (C) Monomer having affinity with non-aqueous medium (D) Present in aqueous medium Among the combinations of the monomer (E) bifunctional monomer (A) to (E) having an affinity for the organic pigment fine particles, it is preferable to combine the components (A), (C) and (E). ), (B), (C), and (E) are more preferably combined, and it is particularly preferable to combine the components (A), (B), (C), (D), and (E).

  As the monomer (A) containing at least one of an acidic group and a basic group, a structure in which the obtained crosslinked polymer compound can be adsorbed to the organic pigment fine particles via acid-base interaction is preferable. A monomer containing a group, a sulfonic acid group, a phosphoric acid group, an amino group, an amide group, or a urea group, more preferably a monomer containing an acidic group such as a carboxylic acid group, a sulfonic acid group, or a phosphoric acid group. Among the acidic groups, carboxylic acid is particularly preferable. Specific examples of such monomers are shown below, but are not limited thereto.

  As the monomer containing the nitrogen-containing heterocycle of (B), the obtained crosslinked polymer compound or the graft polymer forming the same is bonded to organic pigment fine particles by hydrogen bond interaction, van der Waals interaction, dipole-dipole. A structure that can be adsorbed via an interaction or the like is preferable, and a benzimidazolone group, a benzimidazole group, an anthraquinone group, a uracil group, an acridone group, a naphthalimide group, a carbazole group, a pyridyl group, an imidazolyl group, a succinimide group, or a benzopyrrole group Although the monomer which has these etc. is mentioned and a specific example is shown below, it is not limited to these.

The monomer having an affinity for the non-aqueous medium (C) is not particularly limited, but is preferably one that dissolves in the non-aqueous medium used for redispersion described later, and organic pigment fine particles in the non-aqueous medium. More preferably, the dispersion can be stabilized by steric repulsion.
As the monomer of (C), polystyrene skeleton, polymethyl methacrylate skeleton, poly-n-butyl methacrylate skeleton, poly-2-hydroxyethyl methacrylate skeleton, poly-2-ethylhexyl methacrylate skeleton, polyethylene oxide skeleton, polypropylene oxide skeleton, poly It is preferable to contain (ethylene oxide / propylene oxide) skeleton and polycaprolacto skeleton, polystyrene skeleton, polymethyl methacrylate skeleton, polyethylene goxide skeleton, polypropylene oxide skeleton, polymethyl methacrylate skeleton, poly (ethylene oxide / propylene oxide) skeleton, More preferably, it contains a polycaprolactone skeleton, such as a polymethyl methacrylate skeleton, a polypropylene oxide skeleton, and a polymethyl methacrylate. Skeleton, poly (ethylene oxide / propylene oxide) backbone, polycaprolactone skeleton are particularly preferred.

This monomer may be a commercially available product or may be appropriately synthesized.
Specifically, commercially available products include one-end methacryloylated polystyrene oligomer (Mn = 6000, trade name: AS-6, manufactured by Toagosei Chemical Co., Ltd.), one-end methacryloylated polymethyl methacrylate oligomer (Mn = 6000). , Trade name: AA-6, manufactured by Toa Gosei Chemical Co., Ltd.), one-end methacryloylated poly-n-butyl acrylate oligomer (Mn = 6000, trade name: AB-6, Toa Gosei Chemical Co., Ltd.) Manufactured), one-end methacryloylated polymethyl methacrylate / 2-hydroxyethyl methacrylate oligomer (Mn = 7000, trade name: AA-714, manufactured by Toagosei Co., Ltd.), one-end methacryloylated polybutyl methacrylate / 2- Hydroxyethyl methacrylate oligomer (Mn = 7000, trade name: 7 7S, manufactured by Toa Synthetic Chemical Industry Co., Ltd.), one-terminal methacryloylated poly-2-ethylhexyl methacrylate / 2-hydroxyethyl methacrylate oligomer (Mn = 7000, trade names: AY-707S, AY-714S, Toa Synthetic Chemical Industry) Manufactured by Co., Ltd.), methoxypolyethylene glycol methacrylate (trade names: NK ester M-40G, M-90G, M-230G (above, manufactured by Toa Gosei Chemical Co., Ltd.); trade names: BLEMER PME-100, PME -200, PME-400, PME-1000, PME-2000, PME-4000 (manufactured by Nippon Oil & Fats Co., Ltd.)), polyethylene glycol monomethacrylate (trade names: BLEMMER PE-90, PE-200, PE- 350, manufactured by NOF Corporation), polypropylene glycol Nomethacrylate (trade names: Blemmer PP-500, PP-800, PP-1000, manufactured by Nippon Oil & Fats Co., Ltd.), polyethylene glycol polypropylene glycol monomethacrylate (trade name: Blemmer 70PEP-370B, manufactured by Nippon Oil & Fats Co., Ltd.) ), Polyethylene glycol polytetramethylene glycol monomethacrylate (trade name: Blenmer 55PET-800, manufactured by Nippon Oil & Fats Co., Ltd.), polypropylene glycol polytetramethylene glycol monomethacrylate (trade name: Blemmer NHK-5050, Nippon Oil & Fats Co., Ltd.) Etc.).

  Specific examples of synthetic products include alcohols such as dodecylamine, decylamine, 2-ethylhexanol, octanol, hexanol, butanol, propanol, or dodecylamine, decylamine, 2-ethylhexylamine, octylamine, hexylamine, butylamine, propylamine , Polycaprolactone oligomers obtained by ring-opening polymerization of amines such as diethylaminopropylamine and dimethylaminopropylamine and ε-caprolactone, and methoxypolyethylene oxide / polypropylene oxide random copolymer one-end primary amino group oligomers (trade name: Jeffamine 2005, Jeffamine 600, Jeffamine 2070, Jeffamine 1000, Jeffamine 600, HU TSMAN) or monobutoxypolypropylene glycol oligomer (Aldrich), etc., and (meth) acryloyloxyethyl isocyanate or (meth) acrylic acid chloride obtained by reacting with an oligomer having a polymerizable group at one end Can be mentioned. Further, in the synthesis of polycaprolactone oligomer obtained by ring-opening polymerization with ε-caprolactone, the methoxypolyethylene oxide / polypropylene oxide random copolymer one-end primary amino group oligomer may be used instead of the alcohol or amine. Good.

The monomer (D) having an affinity for the organic pigment fine particles present in the aqueous medium is not particularly limited, but preferably has an affinity for the organic pigment fine particles present in the aqueous medium, and is compatible with the non-aqueous medium. It may be a monomer and may be a monomer containing an oligomer or a low molecular weight monomer.
When the monomer (D) is used at the same time as the monomer (C), it is more preferable that the monomer is not the same as the monomer (C) and has higher hydrophilicity than (C).

  As the monomer containing the oligomer of (D), polystyrene skeleton, polymethyl (meth) acrylate skeleton, poly-n-butyl (meth) acrylate skeleton, poly-2-hydroxyethyl (meth) acrylate skeleton, poly-2-ethylhexyl It preferably contains a (meth) acrylate skeleton, a polyethylene oxide skeleton, a polypropylene oxide skeleton, a poly (ethylene oxide / propylene oxide) skeleton, a polycaprolactone skeleton, a polyvinyl pyrrolidone skeleton, a polyvinyl acetamide skeleton, a poly (meth) acrylamide skeleton, Polyethylene oxide skeleton, polypropylene oxide skeleton, poly (ethylene oxide / propylene oxide) skeleton, polycaprolactone skeleton, polyvinyl pyrrolidone skeleton, polyvinyl acetamide skeleton, poly ( It is more preferable to contain data) acrylamide backbone, polyethylene oxide backbone, poly (ethylene oxide / propylene oxide) backbone, polyvinylpyrrolidone backbone, polyvinyl acetamide skeleton, may contain poly (meth) acrylamide backbone particularly preferred.

Moreover, the monomer containing this oligomer may be a commercial item, and what was synthesize | combined suitably may be sufficient as it.
As a commercial item of the monomer containing the oligomer, specifically, methoxypolyethylene glycol methacrylate (trade names: NK ester M-40G, M-90G, M-230G (above, manufactured by Toa Gosei Chemical Co., Ltd.) ); Trade names: Bremer PME-100, PME-200, PME-400, PME-1000, PME-2000, PME-4000 (manufactured by Nippon Oil & Fats Co., Ltd.)), polyethylene glycol monomethacrylate (trade name: BLEMMER PE-90, PE-200, PE-350, manufactured by NOF Corporation, polypropylene glycol monomethacrylate (trade names: BLEMMER PP-500, PP-800, PP-1000, manufactured by NOF Corporation) ), Polyethylene glycol polypropylene glycol monomethacrylate ( Product name: Blemmer 70PEP-370B, manufactured by Nippon Oil & Fats Co., Ltd.), polyethylene glycol polytetramethylene glycol monomethacrylate (Product name: Blemmer 55PET-800, manufactured by Nippon Oil & Fats Co., Ltd.), polypropylene glycol polytetramethylene glycol monomethacrylate (Trade name: BLEMMER NHK-5050, manufactured by NOF Corporation) and the like.

  Specific examples of the synthetic product of the monomer containing the oligomer include a methoxypolyethylene glycol polypropylene glycol random copolymer fragment terminal primary amino group oligomer (trade names: Jeffamine 1000, Jeffamine 2070, manufactured by HUNTSMAN), methoxypolyethylene glycol oligomer (Aldrich). , 2-mercaptoethanol, 3-mercapto-1,2-propanediol, etc. as chain transfer agents, vinylpyrrolidone, 2-hydroxyethyl methacrylate, 2-hydroxyethylacrylamide, acrylamide, vinylacetamide, N, N'-dimethyl (meth) acrylamide, N-methylmethacrylamide, N, N'-diethylacrylamide, N-isopropylacrylic Having a polymerizable group at one end obtained by reacting with olefin, Nt-butylacrylamide, an oligomer obtained by polymerizing allylurea, and (meth) acryloyloxyethyl isocyanate or (meth) acrylic acid chloride An oligomer is mentioned.

  Specific examples of the low molecular weight monomer include vinyl pyrrolidone, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylamide, acrylamide, vinyl acetamide, N, N′-dimethyl (meth) acrylamide, N-methyl methacrylamide, N, N′-diethylacrylamide, N-isopropylacrylamide, Nt-butylacrylamide, allyl urea, isopropenyl methyl ether, vinyl acetate, vinyl propionate, acrylic acid, vinyl pyrrolidone, 2-hydroxyethyl methacrylate, 2-hydroxyethylacrylamide, acrylamide, vinylacetamide, N, N′-dimethyl (meth) acrylamide, N-methylmethacrylamide, N, N′-diethylacrylamide are more preferred. Arbitrariness.

  Although it does not specifically limit as a bifunctional monomer of (E), Only 1 type may be used and 2 or more types may be used together. Further, it is preferable that the copolymerization with the monomers (A) to (D) is good. The functional group of the bifunctional monomer is preferably a (meth) acrylate skeleton, a styrene skeleton, a (meth) acrylamide skeleton, or a divinylamide skeleton, and more preferably a (meth) acrylate skeleton or a styrene skeleton.

  Hereinafter, although the specific example of the bifunctional monomer of (E) is shown, it is not limited to these.

  In the polymer compound obtained by copolymerizing at least one of the monomers (A) to (E), (A) :( B) :( C) :( D) :( E) = (M) 1 to 60): (0 to 50): (20 to 90): (0 to 60): (1 to 20) are preferable, and these mass ratios are appropriately selected so that the sum is 100.

  The polymer compound obtained by copolymerizing at least one of the monomers (A) to (E) can be obtained by radical polymerization of the monomers (A) to (E) in a solvent, for example. . In the radical polymerization, a radical polymerization initiator can be used, and a chain transfer agent (eg, 2-mercaptoethanol and dodecyl mercaptan) can be further used. The pigment dispersant containing the copolymer can also be synthesized with reference to the description in JP-A-2001-31885.

  Specific examples of the crosslinked polymer compound obtained by copolymerizing at least one of the monomers (A) to (E) are shown below, but are not limited thereto. Moreover, in the following specific examples, when each repeating unit is located at the terminal of the constituted polymer compound, it can be understood that the terminal of the repeating unit is substituted with a hydrogen atom or an arbitrary terminal group. The repeating unit of the polymerization ratio e indicates that the cross-linked units are cross-linked and linked, and the repeating units (1-3) to (2-4) of the general formulas (1) and (2) Equivalent to.

Hereinafter, a preferred embodiment of a method for isolating hydrophobic aggregates of organic pigment fine particles obtained using the pigment composition of the present invention will be described.
First, it is preferable that the aggregated liquid is allowed to stand for 0.5 to 2 hours before isolation. Since the aggregate is settled, the supernatant can be removed by decanting or sucking, and the isolation of the aggregate is further facilitated. Further, by performing centrifugation instead of standing, faster aggregate sedimentation is possible, and the time can be shortened.
As an isolation method, various types of filtration methods are possible, and examples thereof include ultrafiltration, centrifugal separation, and filtration with a filter paper or a filter.

  In the case of ultrafiltration, for example, a method used for desalting / concentration of a silver halide emulsion can be applied. Research Disclosure No. 10208 (1972), no. 13 122 (1975) and no. 16 351 (1977) is known. The pressure difference and flow rate that are important as operating conditions can be selected by referring to the characteristic curve described in Haruhiko Oya's “Membrane Utilization Technology Handbook”, Koshobo Publishing (1978), p275. In order to process the particles, it is necessary to find an optimum condition in order to suppress the unnecessary aggregation of particles. There are two methods for replenishing the solvent that is lost due to membrane permeation: a constant volume method in which the solvent is continuously added and a batch method in which the solvent is intermittently added, but the desalting time is relatively short. The formula is preferred. As the solvent to be replenished, pure water obtained by ion exchange or distillation is used. However, a dispersant, a poor solvent for the dispersant may be mixed in pure water, or directly into the organic nanoparticle dispersion. It may be added.

  For the filter filtration, for example, an apparatus such as pressure filtration can be used. Examples of preferable filters include filter paper, nanofilters, and ultrafilters.

  The centrifuge used for concentration of the organic nanoparticles by centrifugation may be any device as long as it can precipitate the organic nanoparticles in the organic nanoparticle dispersion (or the organic nanoparticle concentrated extract). As a centrifuge, for example, in addition to a general-purpose device, a device with a skimming function (a function of sucking the supernatant layer during rotation and discharging it out of the system) or continuous centrifugation for continuously discharging solid matter Machine.

  Centrifugation conditions are preferably 50 to 10000, more preferably 100 to 8000, and particularly preferably 150 to 6000 in terms of centrifugal force (a value representing how many times the gravitational acceleration is applied). Although the temperature at the time of centrifugation is based on the solvent seed | species of a dispersion liquid, -10-80 degreeC is preferable, -5-70 degreeC is more preferable, 0-60 degreeC is especially preferable.

  The isolated aggregate can be washed for the purposes of desalting, dehydration, and removal of excess dispersant. The washing operation may be subjected to ultrafiltration, centrifugation, filtration through a filter paper or filter, and then the washing solution may be added as it is to wash it. Once the aggregate is taken out and reslurried in the washing solution, ultrafiltration, centrifugation, You may isolate by filtration with a filter paper or a filter, and you may perform washing | cleaning which combined them.

  In addition, the washing can be performed not only after the isolation as described above but also before the isolation. This is achieved by allowing the agglomerated nanopigment particle dispersion to stand, removing the supernatant, adding a washing solution, and reslurry. After reslurry, the slurry is allowed to stand and the supernatant liquid is removed and filtered, or may be filtered as it is. When washing is performed before isolation, the aggregates are always wet, so that not only the washing efficiency is increased, but also redispersion described later becomes easier.

  The washing liquid is not particularly limited as long as desalting, dehydration, and removal of excess dispersant / flocculant can be achieved. Specifically, aqueous solvents (for example, water, hydrochloric acid, aqueous sodium hydroxide), alcohol compounds Solvent, amide compound solvent, ketone compound solvent, ether compound solvent, aromatic compound solvent, carbon disulfide solvent, aliphatic compound solvent, nitrile compound solvent, sulfoxide compound solvent, halogen compound solvent, ester compound solvent, ionic liquid, these An aqueous solvent, an alcohol compound solvent, a ketone compound solvent, an ether compound solvent, a nitrile compound solvent, a sulfoxide compound solvent, an ester compound solvent, an amide compound solvent, or a mixture thereof is preferable, particularly an aqueous solvent, Alcohol compound solvent, ester compound solvent, Nito Le compound solvent.

  The isolated hydrophobic aggregate preferably contains a dispersant and a hydrophobizing dispersant in addition to the organic pigment fine particles. The crosslinked polymer compound may function as a hydrophobizing dispersant, and the dispersant is preferably present in an amount of 1% by mass to 1000% by mass with respect to the pigment. Furthermore, 5 mass% or more and 200 mass% or less are more preferable, and 10 mass% or more and 100 mass% or less are especially preferable. Even if it is less than 1% by mass or more than 1000% by mass, problems such as poor dispersion in a non-aqueous medium are likely to occur. The hydrophobizing dispersant is preferably 1% by mass or more and 1000% by mass or less, more preferably 10% by mass or more and 200% by mass or less, and more preferably 20% by mass or more and 100% by mass or less with respect to the pigment. If the amount is less than 1% by mass, the dispersion is poor. If the amount exceeds 1000% by mass, problems such as an increase in viscosity at the time of redispersion tend to occur.

  The dispersant has a function of promoting and holding adsorption of the hydrophobizing dispersant to the organic pigment fine particles when the organic pigment fine particles are dispersed in a non-aqueous medium. Therefore, if the amount of the dispersant is too small, the hydrophobizing dispersant may be desorbed from the organic pigment fine particles, resulting in poor dispersion during redispersion in a non-aqueous medium. On the other hand, if the dispersant is hydrophilic and the amount thereof is too large, the amount of the dispersant for hydrophobizing becomes relatively smaller than that of the dispersant. Therefore, the hydrophobizing effect may be insufficient in an aqueous medium, and in a non-aqueous medium, dispersion may be poor when redispersed. As for the hydrophobizing dispersant, if the amount is too small, the hydrophobizing effect of the hydrophobizing dispersant in an aqueous medium may be insufficient. On the other hand, dispersion may be poor in a non-aqueous medium. When the amount of the hydrophobizing dispersant is too large, an extra hydrophobizing dispersant that cannot be adsorbed on the organic pigment fine particles is generated, and the viscosity may increase during redispersion.

  The isolated agglomerates may be re-dispersed as described below, or may be re-dispersed after being wetted with a re-dispersing solvent (described later), or after being dried and taken out as a powder of organic nanoparticle dispersion Redispersion may be performed.

The drying method is not particularly limited, and examples include lyophilization and vacuum drying.
The lyophilization method is not particularly limited, and any method that can be used by those skilled in the art may be adopted. For example, a refrigerant direct expansion method, an overlap refrigeration method, a heat medium circulation method, a triple heat exchange method, and an indirect heating freezing method can be mentioned, preferably a refrigerant direct expansion method, an indirect heating freezing method, more preferably an indirect heating freezing method. It is good to use. In any method, it is preferable to perform freeze-drying after preliminary freezing. The pre-freezing conditions are not particularly limited, but it is necessary that the sample to be freeze-dried is completely frozen.

  Indirect heating freezing equipment includes small freeze dryer, FTS freeze dryer, LYOVAC freeze dryer, experimental freeze dryer, research freeze dryer, triple heat exchange vacuum freeze dryer, mono-cooling freeze dryer , HULL freeze dryers, preferably small freeze dryers, laboratory freeze dryers, research freeze dryers, monocooling freeze dryers, more preferably small freeze dryers, monocooling freeze dryers Should be used.

  Although the temperature of freeze-drying is not specifically limited, For example, it is -190--4 degreeC, Preferably it is -120--20 degreeC, More preferably, it is about -80--60 degreeC. The pressure of lyophilization is not particularly limited, and can be appropriately selected by those skilled in the art. For example, the pressure may be 0.1 to 35 Pa, preferably 1 to 15 Pa, and more preferably about 5 to 10 Pa. The freeze-drying time is, for example, 2 to 48 hours, preferably 6 to 36 hours, and more preferably about 16 to 26 hours. However, these conditions can be appropriately selected by those skilled in the art. Regarding the freeze-drying method, for example, Formulation Machine Technology Handbook: Formulation Machine Technology Study Group, Jinshokan, p. 120-129 (September 2000); Vacuum Handbook: Japan Vacuum Technology Co., Ltd., Ohm, p. 328-331 (1992); Journal of the Research Group on Freezing and Drying: Koji Ito et al. 15, p. 82 (1965) or the like.

  The apparatus used for concentration of the organic nanoparticles by drying under reduced pressure is not particularly limited as long as the solvent of the organic nanoparticle dispersion (or organic nanoparticle concentrated extract) can be evaporated. For example, a general-purpose vacuum dryer and a rotary pump, an apparatus that can be heated and reduced in pressure while stirring the liquid, and an apparatus that can be continuously dried by passing the liquid through a heated and reduced pressure tube.

  The heating and drying temperature is preferably 30 to 230 ° C, more preferably 35 to 200 ° C, and particularly preferably 40 to 180 ° C. The pressure during decompression is preferably 100 to 100,000 Pa, more preferably 300 to 90,000 Pa, and particularly preferably 500 to 80,000 Pa.

In the present invention, the organic pigment fine particles in an agglomerated state can be finely dispersed as required (in the present invention, fine dispersion or redispersion is a method of deaggregating particles in a dispersion and dispersing the degree of dispersion). ). In the present invention, the obtained hydrophobic aggregate is preferably redispersed in a non-aqueous medium. (The dispersion thus obtained may be referred to as a non-aqueous dispersion.)
The non-aqueous medium refers to a medium other than the aqueous medium, and a ketone compound solvent, an ester compound solvent, and an aromatic compound solvent are preferable. Specific examples include methyl ethyl ketone, cyclohexanone, ethyl acetate, butyl acetate, 2- (1-methoxy) propyl acetate, nitrobenzene, chlorobenzene, and dichlorobenzene. Among them, methyl ethyl ketone, cyclohexanone, 2- (1-methoxy) propyl acetate Chlorobenzene is preferred.

  In order to make the agglomerated organic pigment fine particles described above into a good dispersion state that can be promptly filtered, it is preferable to obtain flocs obtained by agglomerating the organic pigment fine particles to such an extent that they can be redispersed. Here, the floc means an aggregate of fine particles that have been weakly aggregated (soft aggregated) to such an extent that they can be redispersed. The hydrophilic aggregate and the hydrophobic aggregate are also preferably floc. By making the organic pigment fine particles floc in this way, for example, the organic pigment fine particles deposited in an aqueous mixture can be quickly separated from the medium by filtration or the like. Then, the separated floc (soft agglomerate) can be re-dispersed in an organic solvent suitable for the production of a color filter to efficiently produce an organic solvent-based pigment dispersion composition (non-aqueous dispersion composition). That is, when the mixed solvent of the good solvent and the poor solvent is an aqueous solvent, the dispersion medium (continuous phase) can be switched by efficiently replacing it with a third solvent made of an organic solvent.

  In addition, the degree of dispersion using a normal dispersion method is insufficient for the formation of fine particles, and a method with higher fineness efficiency may be required. Even in such strongly agglomerated organic particles (in the present invention, agglomerated organic particles are those in which organic particles such as agglomerates are gathered by a secondary force, and the primary particles are nanometer-sized. (It may also be an agglomerated nanoparticle.)) By containing an organic polymer compound having a mass average molecular weight of 1000 or more in the agglomerated organic particle liquid, a dispersion in which organic particles are suitably finely dispersed can be obtained ( In the present invention, the aggregated organic particle liquid refers to a liquid containing the aggregated organic particles in the liquid, and the aggregated organic particles may be contained even in a dispersion, a concentrated liquid, a paste, a slurry, or the like. More specifically, by using the above organic polymer compound, good fine dispersibility (characteristic that realizes a uniform and fine particle size) and dispersion when deposited in a mixture of a good solvent and a poor solvent Stability (characteristic that maintains a uniform and fine particle size for a long period of time) can be maintained even after switching the medium to an organic solvent suitable for the color filter and redispersing, thereby realizing high performance in the color filter. In addition, the organic polymer compound interacts with the colorability of the organic nanopigment fine particles without interfering with the optical characteristics of the color filter, thereby realizing high performance in the color filter.

  As a method for finely dispersing such an aggregate of nanoparticles, for example, a dispersion method using ultrasonic waves or a method of applying physical energy can be used.

  The ultrasonic irradiation device used preferably has a function capable of applying an ultrasonic wave of 10 kHz or higher, and examples thereof include an ultrasonic homogenizer and an ultrasonic cleaner. When the liquid temperature rises during ultrasonic irradiation, thermal aggregation of the nanoparticles occurs (see Non-Patent Document 1). Therefore, the liquid temperature is preferably 1 to 100 ° C, more preferably 5 to 60 ° C. The temperature control method can be performed by controlling the dispersion temperature, controlling the temperature of the temperature adjusting layer that controls the temperature of the dispersion, or the like.

  There are no particular restrictions on the dispersing machine used to disperse the concentrated organic nanoparticles by applying physical energy. For example, kneader, roll mill, atrider, super mill, dissolver, homomixer, sand mill, etc. Machine. Further, a high-pressure dispersion method and a dispersion method using fine particle beads are also preferable.

  As a preferred method for producing the organic nanoparticle dispersion, the viscosity at 25 ° C. after kneading and dispersing the colorant with the resin component is 10,000 mPa · s or higher, desirably 100,000 mPa · s or higher. The method of kneading and dispersing as described above, and then adding a solvent and finely dispersing so that the viscosity after the fine dispersion treatment is 1,000 mPa · s or less, desirably 100 mPa · s or less, is relatively low. .

  The machines used in the redispersion process are two rolls, three rolls, ball mills, tron mills, dispersers, kneaders, kneaders, homogenizers, blenders, single- and twin-screw extruders, etc., which disperse while giving a strong shearing force. . Next, a solvent was added, and a vertical or horizontal sand grinder, a pin mill, a slit mill, an ultrasonic disperser, a high pressure disperser, etc. were used, and it was made of glass having a particle diameter of 0.1 to 1 mm, zirconia, or the like. Fine dispersion with beads. Furthermore, it is possible to perform a fine dispersion treatment using fine particle beads of 0.1 mm or less.

  It is also possible to disperse the main pigment and the complementary pigment separately, and then mix the dispersions of the two to add further dispersion treatment, or to disperse the main pigment and the complementary pigment together.

  For details on dispersion, see T.W. C. It is also described in “Paint Flow and Pigment Dispersion” by Patton (published by John Wiley and Sons, 1964), and this method may be used.

  For the purpose of improving the dispersibility of the organic pigment fine particles, an ordinary pigment dispersant or a surfactant can be added to the redispersed organic pigment fine particle dispersion. As these dispersants, many kinds of compounds are used. For example, a phthalocyanine derivative (commercially available product EFKA-6745 (manufactured by Efka)), Solsperse 5000 (manufactured by Geneca), organosiloxane polymer KP341 ( Shin-Etsu Chemical Co., Ltd.), (meth) acrylic acid (co) polymer polyflow No. 75, no. 90, no. 95 (manufactured by Kyoeisha Yushi Chemical Co., Ltd.), W001 (manufactured by Yusho Co., Ltd.), and the like; polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene octylphenyl Nonionic surfactants such as ether, polyoxyethylene nonylphenyl ether, polyethylene glycol dilaurate, polyethylene glycol distearate, sorbitan fatty acid ester; anionic surfactants such as W004, W005, W017 (manufactured by Yusho); EFKA- 46, EFKA-47, EFKA-47EA, EFKA polymer 100, EFKA polymer 400, EFKA polymer 401, EFKA polymer 450 (manufactured by Morishita Sangyo Co., Ltd.), Disperse Aid 6, Polymer dispersing agents such as ISPERSIDE 8, DISPERSIDE 15 and DISPERSIDE 9100 (manufactured by San Nopco); Solsols such as Solsperse 3000, 5000, 9000, 12000, 13240, 13940, 17000, 24000, 26000, 28000 Dispersing agent (manufactured by Zeneca); Adeka Pluronic L31, F38, L42, L44, L61, L64, F68, L72, P95, F77, P84, F87, P94, L101, P103, F108, L121, P-123 (Asahi Denka Co., Ltd.) and Isonet S-20 (Sanyo Kasei Co., Ltd.). Further, the pigment dispersant described in JP 2000-239554 A, the compound (C) described in JP-B-5-72943, the compound of Synthesis Example 1 described in JP 2001-31885 A, and the like are also preferably used. Can be used.

  In the organic nanoparticle dispersion composition after redispersion, the organic nanoparticles (primary particles) can be finely dispersed particles, and the particle size can be preferably 1 to 200 nm, and 2 to 100 nm. More preferred is 5 to 50 nm. Further, the Mv / Mn of the particles after redispersion is preferably 1.0 to 2.0, more preferably 1.0 to 1.8, and 1.0 to 1.5. Is particularly preferred.

  According to the present invention, pigment fine particles can be efficiently concentrated and redispersed in spite of a minute particle size of nanometer size (for example, 10 to 100 nm). It can be set as the colored photosensitive resin composition mentioned later. For this reason, when these compositions are used in a color filter, the optical density is high, the filter surface is excellent in uniformity, the contrast is high, and image noise can be reduced.

  Furthermore, the organic pigment fine particles contained in the organic pigment fine particle dispersion composition and the colored photosensitive composition can be finely dispersed in a highly and uniform manner, thereby exhibiting a high color density with a thin film thickness. For example, a color filter or the like can be thinned.

  In addition, the organic pigment fine particle dispersion composition and the colored photosensitive resin composition are excellent as an image forming material for producing, for example, a color proof or a color filter by containing a pigment having a clear color tone and high coloring power. ing.

  Furthermore, with respect to an alkaline developer used for exposure / development in the formation of a colored image, an organic nanoparticle dispersion composition, a colored photosensitive resin composition, a binder (binder) soluble in an alkaline aqueous solution It can be used and can meet environmental requirements.

  In addition, organic solvents having an appropriate drying property can be used as the solvent (pigment dispersion medium) used in the organic pigment fine particle dispersion composition and the colored photosensitive resin composition, and the requirements are satisfied in terms of drying after coating. can do.

[Colored photosensitive resin composition]
The colored photosensitive resin composition of the present invention contains at least (a) an organic pigment composition, (b) a binder, (c) a monomer or oligomer, and (d) a photopolymerization initiator or photopolymerization initiator system. Hereinafter, each component of the colored photosensitive resin composition of the present invention will be described.

(A) Organic pigment composition The method for preparing the organic pigment composition has already been described in detail. The content of the organic nano pigment particles is 3 to 90% by mass with respect to the total solid content in the colored photosensitive resin composition (in the present invention, the total solid content refers to the total composition excluding the organic solvent). Is preferable, 20-80 mass% is more preferable, and 25-60 mass% is further more preferable. If this amount is too large, the viscosity of the dispersion increases, which may cause problems in production suitability. If the amount is too small, the coloring power is not sufficient. The organic nano pigment particles functioning as a colorant preferably have a particle size of 0.1 μm or less, particularly 0.08 μm or less. Moreover, you may use it in combination with a normal pigment for toning. As the pigment, those described above can be used. In the present invention, the organic nanoparticles are preferably used as the organic nanopigment non-aqueous dispersion.

(B) Binder As the binder in the colored photosensitive resin composition, the above-described polymer compound having a mass average molecular weight of 1000 or more can be preferably used. As for content of a binder, 15-50 mass% is common with respect to the total solid of a colored photosensitive resin composition, and 20-45 mass% is preferable. If the amount is too large, the viscosity of the composition becomes too high, causing a problem in production suitability. If the amount is too small, there is a problem in forming a coating film.

(C) Monomer or oligomer The monomer or oligomer contained in the colored photosensitive resin composition of the present invention is a monomer or oligomer that has two or more ethylenically unsaturated double bonds and undergoes addition polymerization upon irradiation with light. It is preferable. Examples of such monomers and oligomers include compounds having at least one addition-polymerizable ethylenically unsaturated group in the molecule and having a boiling point of 100 ° C. or higher at normal pressure. Examples include monofunctional acrylates and monofunctional methacrylates such as dipentaerythritol hexa (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate and phenoxyethyl (meth) acrylate; polyethylene glycol di ( (Meth) acrylate, polypropylene glycol di (meth) acrylate, trimethylolethane triacrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane diacrylate, neopentylglycol di (meth) acrylate, pentaerythritol tetra (meth) acrylate, Pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipenta Rithritol penta (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (acryloyloxypropyl) ether, tri (acryloyloxyethyl) isocyanurate, tri (acryloyloxyethyl) cyanurate, glycerin tri (meth) acrylate And polyfunctional acrylates and polyfunctional methacrylates such as those obtained by adding ethylene oxide or propylene oxide to a polyfunctional alcohol such as trimethylolpropane or glycerin and then (meth) acrylated. Also suitable are compounds obtained by adding ethylene oxide or propylene oxide to a polyfunctional alcohol and then (meth) acrylated as in general formulas (1) and (2) described in JP-A-10-62986. As mentioned.

  Further, urethane acrylates described in JP-B-48-41708, JP-B-50-6034 and JP-A-51-37193; JP-A-48-64183, JP-B-49-43191 And polyester acrylates described in Japanese Patent Publication No. 52-30490; polyfunctional acrylates and methacrylates such as epoxy acrylates which are reaction products of epoxy resin and (meth) acrylic acid.

  Among these, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and dipentaerythritol penta (meth) acrylate are preferable.

  In addition, “polymerizable compound B” described in JP-A-11-133600 can also be mentioned as a preferable example.

  These monomers or oligomers (monomers or oligomers having a molecular weight of 200 to 1000 are preferred) may be used alone or in admixture of two or more, and may be used for the total solid content of the colored photosensitive resin composition. The content is generally 5 to 50% by mass, and preferably 10 to 40% by mass. If this amount is too large, it becomes difficult to control the developability, which causes a problem in production suitability. If the amount is too small, the curing power at the time of exposure is insufficient.

(D) Photopolymerization initiator or photopolymerization initiator system The photopolymerization initiator or photopolymerization initiator system contained in the colored photosensitive resin composition of the present invention (in the present invention, the photopolymerization initiator system is a plurality of compounds) And a vicinal polyketaldonyl compound disclosed in US Pat. No. 2,367,660, which is described in US Pat. No. 2,448,828. An acyloin ether compound, an aromatic acyloin compound substituted with an α-hydrocarbon described in US Pat. No. 2,722,512, a polynuclear quinone compound described in US Pat. Nos. 3,046,127 and 2,951,758, A combination of a triarylimidazole dimer and a p-aminoketone described in US Pat. No. 3,549,367, JP-B 51-4 Benzothiazole compounds and trihalomethyl-s-triazine compounds described in US Pat. No. 516, trihalomethyl-triazine compounds described in US Pat. No. 4,239,850, trihalomethyl described in US Pat. No. 4,221,976 An oxadiazole compound etc. can be mentioned. In particular, trihalomethyl-s-triazine, trihalomethyloxadiazole, and triarylimidazole dimer are preferable.

  In addition, “polymerization initiator C” described in JP-A-11-133600, oxime-based compounds such as 1-phenyl-1,2-propanedione-2- (o-ethoxycarbonyl) oxime, O— Benzoyl-4 '-(benzmercapto) benzoyl-hexyl-ketoxime, 2,4,6-trimethylphenylcarbonyl-diphenyl phosphonyl oxide, hexafluorophospho-trialkylphenyl phosphonium salt and the like may be mentioned as suitable ones. it can.

  These photopolymerization initiators or photopolymerization initiator systems may be used singly or as a mixture of two or more, but it is particularly preferable to use two or more. When at least two kinds of photopolymerization initiators are used, display characteristics, particularly display unevenness, can be reduced.

The content of the photopolymerization initiator or the photopolymerization initiator system with respect to the total solid content of the colored photosensitive resin composition is generally 0.5 to 20% by mass, and preferably 1 to 15% by mass. If this amount is too large, the sensitivity becomes too high and control becomes difficult. If the amount is too small, the exposure sensitivity becomes too low. As radiation that can be used for exposure, ultraviolet rays such as g-line and i-line are particularly preferably used. Irradiation dose is more preferably preferably ^{10~1000mJ / cm 2 5~1500mJ / cm 2} , and most preferably 10 to 500 mJ / cm ^2.

(Other additives)
〔solvent〕
In the colored photosensitive resin composition of the present invention, an organic solvent may be further used in addition to the above components. Examples of organic solvents include, but are not limited to, esters such as ethyl acetate, n-butyl acetate, isobutyl acetate, amyl formate, isoamyl acetate, isobutyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, Alkyl esters, methyl lactate, ethyl lactate, methyl oxyacetate, ethyl oxyacetate, butyl oxyacetate, methyl methoxyacetate, ethyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, methyl 3-oxypropionate, 3 -3-oxypropionic acid alkyl esters such as ethyl oxypropionate; methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, 2-oxypropionic acid Chill, ethyl 2-oxypropionate, propyl 2-oxypropionate, methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate Methyl 2-oxy-2-methylpropionate, ethyl 2-oxy-2-methylpropionate, methyl 2-methoxy-2-methylpropionate, ethyl 2-ethoxy-2-methylpropionate, methyl pyruvate, pyrubin Ethyl acetate, propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl 2-oxobutanoate, ethyl 2-oxobutanoate, etc .; ethers such as diethylene glycol dimethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ether Ren glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, propylene glycol methyl ether acetate, etc .; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, cyclohexanol, 2-heptanone, 3-heptanone, etc .; Aromatic hydrocarbons such as toluene, xyles and the like can be mentioned. Among these solvents, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl cellosolve acetate, ethyl lactate, butyl acetate, methyl 3-methoxypropionate, 2-heptanone, cyclohexanone, ethyl carbitol acetate, butyl carbitol Acetate, propylene glycol methyl ether acetate and the like are preferably used as the solvent in the present invention. These solvents may be used alone or in combination of two or more.

  Moreover, the solvent whose boiling point is 180 to 250 degreeC can be used if needed. Examples of these high-boiling solvents include the following. Diethylene glycol monobutyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, 3,5,5-trimethyl-2-cyclohexen-1-one, butyl lactate, dipropylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol di Acetate, propylene glycol-n-propyl ether acetate, diethylene glycol diethyl ether, 2-ethylhexyl acetate, 3-methoxy-3-methylbutyl acetate, γ-butyllactone, tripropylene glycol methyl ethyl acetate, dipropylene glycol-n-butyl acetate, Propylene glycol phenyl ether acetate, 1, - butanediol diacetate.

  As for content of a solvent, 10-95 mass% is preferable with respect to the resin composition whole quantity.

[Surfactant]
Conventionally used color filters have a problem that the color of each pixel becomes dark in order to achieve high color purity, and the film thickness unevenness of the pixel is recognized as color unevenness as it is. Therefore, it has been demanded to improve the film thickness variation during the formation (application) of the photosensitive resin layer, which directly affects the pixel film thickness.

  In the transfer material using the color filter of the present invention or the colored photosensitive resin composition of the present invention, the film thickness can be controlled to be uniform, and coating unevenness (color unevenness due to film thickness variation) can be effectively prevented. It is preferable that an appropriate surfactant is contained in the colored photosensitive resin composition.

  Preferred examples of the surfactant include surfactants disclosed in JP-A Nos. 2003-337424 and 11-133600. The content of the surfactant is preferably 5% by mass or less with respect to the total amount of the resin composition.

(Thermal polymerization inhibitor)
The colored photosensitive resin composition of the present invention preferably contains a thermal polymerization inhibitor. Examples of the thermal polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, p-methoxyphenol, di-t-butyl-p-cresol, pyrogallol, t-butylcatechol, benzoquinone, 4,4′-thiobis (3-methyl). -6-t-butylphenol), 2,2'-methylenebis (4-methyl-6-t-butylphenol), 2-mercaptobenzimidazole, phenothiazine and the like. The content of the thermal polymerization inhibitor is preferably 1% by mass or less based on the total amount of the resin composition.

[Dyes and pigments to be used supplementarily]
In addition to the said colorant (pigment), a colorant (dye, pigment) can be added to the colored photosensitive resin composition of this invention as needed. In the case of using a pigment among the colorants, it is desirable that the pigment is uniformly dispersed in the colored photosensitive resin composition. Therefore, the particle diameter is preferably 0.1 μm or less, particularly 0.08 μm or less.

  Specific examples of the dye or pigment include the colorant described in JP-A-2005-17716 [0038] to [0040] and JP-A-2005-361447 [0068] to [0072]. And the colorants described in JP-A-2005-17521 [0080] to [0088] can be suitably used. The content of the auxiliary dye or pigment is preferably 5% by mass or less based on the total amount of the resin composition.

[Ultraviolet absorber]
The colored photosensitive resin composition of the present invention may contain an ultraviolet absorber as necessary. Examples of the ultraviolet absorber include salicylate-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based, nickel chelate-based, hindered amine-based compounds and the like in addition to the compounds described in JP-A-5-72724.

  Specifically, phenyl salicylate, 4-t-butylphenyl salicylate, 2,4-di-t-butylphenyl-3 ′, 5′-di-t-4′-hydroxybenzoate, 4-t-butylphenyl salicylate 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2 '-Hydroxy-3'-t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, ethyl-2-cyano-3,3-diphenyl acrylate, 2,2'-hydroxy-4-methoxybenzophenone, nickel Dibutyldithiocarbamate, bis (2,2,6,6-tetramethyl-4-pyridine Sebacate, 4-tert-butylphenyl salicylate, phenyl salicylate, 4-hydroxy-2,2,6,6-tetramethylpiperidine condensate, succinic acid-bis (2,2,6,6-tetramethyl-4 -Piperenyl) -ester, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 7-{[4-chloro-6- (diethylamino) -5 And triazin-2-yl] amino} -3-phenylcoumarin. As for content of a ultraviolet absorber, 5 mass% or less is preferable with respect to the resin composition whole quantity.

  In addition, the colored photosensitive resin composition of the present invention may contain “adhesion aid” described in JP-A No. 11-133600, other additives and the like in addition to the above additives.

[Coating film of colored photosensitive resin composition]
The components contained in the coating film using the colored photosensitive resin composition of the present invention are the same as those already described in the section of [Colored photosensitive resin composition]. Moreover, although the thickness of the coating film using the colored photosensitive resin composition of this invention can be suitably determined with the use, it is preferable that it is 0.5-5.0 micrometers, and 1.0-3. More preferably, it is 0 μm. In the coating film using the colored photosensitive resin composition of the present invention, (c) the monomer or oligomer contained therein is polymerized to form a colored photosensitive resin composition polymer film, and a color filter having the same is prepared. (The production of the color filter will be described later). Polymerization of the polymerizable monomer or polymerizable oligomer can be carried out by allowing (d) a photopolymerization initiator or a photopolymerization initiator system to act upon irradiation with light.

<Color filter and manufacturing method thereof>
Next, the color filter of the present invention and the manufacturing method thereof will be described.

  The color filter of the present invention is characterized in that it has a colored pattern formed on the support using the photocurable composition (colored photosensitive resin composition) of the present invention.

  Hereinafter, the color filter of the present invention will be described in detail through its manufacturing method (color filter manufacturing method of the present invention).

  The method for producing a color filter of the present invention comprises a step of forming a photosensitive film by applying the photocurable composition of the present invention directly or through another layer (hereinafter referred to as “photosensitive film formation” as appropriate). Abbreviated as “step”), a step of pattern exposure (exposure through a mask) of the formed photosensitive film (hereinafter abbreviated as “exposure step” as appropriate), and a photosensitive film after exposure. And a step of developing a colored pattern (hereinafter, abbreviated as “development step” as appropriate).

Hereinafter, each process in the manufacturing method of the color filter of this invention is demonstrated.
(Photosensitive film forming process)
In the photosensitive film forming step, the photocurable composition of the present invention is applied (applied) directly or on a substrate having another layer to form a photosensitive film.

  Examples of the substrate that can be used in this step include soda glass, Pyrex (registered trademark) glass, quartz glass, and those in which a transparent conductive film is attached to these substrates, photoelectric sensors used in image sensors, and the like. Examples include a conversion element substrate such as a silicon substrate and a complementary metal oxide semiconductor (CMOS). These substrates may have black stripes that separate pixels.

  Further, if necessary, an undercoat layer (other layers) may be provided on these substrates for improving adhesion to the upper layer, preventing diffusion of substances, or flattening the substrate surface.

  As a coating method of the photocurable composition of the present invention on the substrate, various coating methods such as slit coating, ink jet method, spin coating, cast coating, roll coating, screen printing method and the like can be applied.

  As a coating film thickness of a photocurable composition, 0.1-10 micrometers is preferable, 0.2-5 micrometers is more preferable, 0.2-3 micrometers is further more preferable.

The photosensitive film coated on the substrate can be dried (prebaked) at a temperature of 50 ° C. to 140 ° C. for 10 to 300 seconds using a hot plate, an oven, or the like.
(Exposure process)
In the exposure step, the photosensitive film formed in the photosensitive film forming step is exposed through a mask having a predetermined mask pattern, that is, pattern exposure is performed.

  In this step, only the coating film portion irradiated with light can be cured by exposing the photosensitive film as the coating film through a predetermined mask pattern.

As radiation that can be used for exposure, ultraviolet rays such as g-line and i-line are particularly preferably used. Irradiation dose is more preferably preferably ^{10~1000mJ / cm 2 5~1500mJ / cm 2} , and most preferably 10 to 500 mJ / cm ^2.

If the color filter of the present invention is a liquid crystal display device, it is more preferably preferably 10~150mJ / cm ² 5~200mJ / cm ² within the above range, and most preferably 10 to 100 mJ / cm ^2. Further, when the color filter of the present invention is for a solid-state imaging device, more preferably 30~1500mJ / cm ² is preferably 50~1000mJ / cm ² within the above range, and most preferably 80~500mJ / cm ^2.

(Development process)
Next, by performing development processing, the unexposed portion in the exposure step is eluted in the developer, and only the photocured portion remains. Any developer can be used as long as it dissolves the film of the photocurable composition in the uncured part while not dissolving the cured part. Specifically, a combination of various organic solvents or an alkaline aqueous solution can be used.

  The development temperature is usually 20 ° C. to 30 ° C., and the development time is 20 to 90 seconds.

  Examples of the organic solvent include the solvents described above that can be used in preparing the pigment dispersion composition or the photocurable composition of the present invention.

  Examples of the alkaline aqueous solution include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogencarbonate, sodium oxalate, sodium metasuccinate, aqueous ammonia, ethylamine, diethylamine, dimethylethanolamine, tetramethylammonium hydroxide, Concentration of an alkaline compound such as tetraethylammonium hydroxide, choline, pyrrole, piperidine, 1,8-diazabicyclo- [5,4,0] -7-undecene, in a concentration of 0.001 to 10% by mass, preferably 0.01 to An alkaline aqueous solution diluted with pure water so as to be 1% by mass is preferably used as the developer.

  In the case where a developer composed of such an alkaline aqueous solution is used, it is generally washed (rinsed) with pure water after development.

  After the development step, excess developer is washed away and dried, followed by heat treatment (post-bake).

  The post-baking is a heat treatment after development for complete curing, and usually a heat curing treatment at 100 ° C. to 240 ° C. is performed. When the substrate is a glass substrate or a silicon substrate, 200 ° C. to 240 ° C. is preferable in the above temperature range.

  This post-bake treatment is performed continuously or batchwise using a heating means such as a hot plate, a convection oven (hot air circulation dryer), a high-frequency heater, or the like so that the coating film after development is in the above-described condition. be able to.

  By repeating the photosensitive film formation step, the exposure step, and the development step (and heat treatment as necessary) described above for the desired number of hues, a color filter having a desired hue is manufactured.

  When a film is formed by applying a photocurable composition on a substrate, the dry thickness of the film is generally 0.3 to 5.0 μm, preferably 0.5 to 3.5 μm, most desirably It is 1.0-2.5 micrometers.

  As the substrate, for example, non-alkali glass, soda glass, Pyrex (registered trademark) glass, quartz glass used for liquid crystal display elements or the like, and those obtained by attaching a transparent conductive film to these, solid-state imaging elements, etc. Examples of the photoelectric conversion element substrate include a silicon substrate and a plastic substrate. On these substrates, usually, black stripes for isolating each pixel are formed.

  The plastic substrate preferably has a gas barrier layer and / or a solvent resistant layer on its surface.

  As the use of the photocurable composition, the use mainly for the pixel of the color filter has been mainly described, but it goes without saying that the photocurable composition can also be applied to a black matrix provided between the pixels of the color filter. The black matrix is the same as the above-described pixel manufacturing method except that a black colorant such as carbon black or titanium black is added as a colorant to the photocurable composition of the present invention. The film can be developed and then post-baked to accelerate the curing of the film.

  EXAMPLES Hereinafter, although this invention is demonstrated in more detail based on an Example, this invention is limited to this and is not interpreted.

<Example 1>
[Preparation of organic nano pigment particle aqueous dispersion]
C. I. Pigment Red 254 (1.5 parts by mass) and polyvinylpyrrolidone (K-25 (trade name), manufactured by Wako Pure Chemical Industries, 3 parts by mass) were added to dimethyl sulfoxide (DMSO) (23.7 parts by mass) and stirred. did. 26 mass% tetramethylammonium hydroxide aqueous solution (1.8 mass parts) was added to this solution, and the pigment solution A was prepared. On the other hand, water (270 parts by mass) to which acetic acid (1.5 parts by mass) was added was prepared as the pigment-insoluble solvent B.
While the pigment insoluble solvent B was stirred at 500 rpm with a GK-0222-10 type Lamond Stirrer (trade name) manufactured by Fujisawa Pharmaceutical Co., Ltd. at 30 ° C., the pigment solution A was added to the pigment insoluble solvent B by Nippon Precision Science Co., Ltd. The organic nanopigment particles were crystallized by injection at a flow rate of 100 mL / min with an NP-KX-500 large-capacity pulsating flow pump (trade name) to obtain hydrophilic aggregates of organic nanopigment particles. The size of the primary particles of the obtained organic nanopigment particles was evaluated with a transmission electron microscope. The results are shown in Table 1.

[Addition of hydrophobizing dispersant]
As a hydrophobizing dispersant, a crosslinked polymer compound P-1 (mass average molecular weight 9600) (0.75 part by mass) is dissolved in acetone (200 parts by mass), and the above-described hydrophilic aggregates of organic nanoparticles (2 Next particle) was added to a dispersion (300 parts by mass) and stirred for 0.5 hour. After standing for 0.5 hour, the resulting hydrophobic aggregates were allowed to settle, and the supernatant was removed by decantation.

[Isolation / Washing / Drying]
The above-mentioned aggregate was filtered off with a filter paper (manufactured by ADVANTEC, No. 2), and washed with water (300 parts by mass). The obtained solid was vacuum-dried overnight at room temperature.

[Redistribution]
The following non-aqueous solvent 1-methoxy-2-propyl acetate (formula Q) (4 parts by mass) is added to this organic pigment solid (1 part by mass), and an ultrasonic homogenizer US series (trade name) manufactured by Nippon Seimitsu Seisakusho is used. Using this, ultrasonic irradiation was performed for 3 hours to obtain an organic nano pigment particle non-aqueous dispersion (pigment dispersion composition A) using the following non-aqueous solvent as a dispersion medium.

(Evaluation test)
(1) Contrast Evaluation The obtained pigment dispersion composition A was applied on a glass substrate so as to have a thickness of 2 μm, thereby preparing a sample. As a backlight unit, a three-wavelength cold-cathode tube light source (FWL18EX-N (trade name) manufactured by Toshiba Lighting & Technology Co., Ltd.) with a diffusion plate is used, and two polarizing plates (polarized light manufactured by Sanritsu Co., Ltd.) This sample is placed between the plates HLC2-2518 (trade name), and the amount of transmitted light when the polarization axis is parallel and when the polarization axis is parallel is measured, and the ratio is defined as the contrast (“1990 7th Color” Optical conference, 512 color display 10.4 "size TFT-LCD color filter, Ueki, Koseki, Fukunaga, Yamanaka" etc.). A color luminance meter (BM-5 manufactured by Topcon Corporation) was used for the measurement of chromaticity. Two polarizing plates, a sample, and a color luminance meter are installed at a position where the polarizing plate is 13 mm from the backlight, and a cylinder having a diameter of 11 mm and a length of 20 mm is installed at a position of 40 mm to 60 mm. Was measured on a color luminance meter installed at a position of 400 mm through a polarizing plate installed at a position of 100 mm. The measurement angle of the color luminance meter was set to 2 °. The light amount of the backlight was set so that the luminance when the two polarizing plates were installed in parallel Nicol was 1280 cd / m ² without the sample being installed. Further, the same evaluation was performed for the pigment dispersion composition A after one week, and it was used as an index of stability according to elapsed time.

<Example 2>
The same operation as in Example 1 was performed except that the crosslinked polymer compound P-1 in Example 1 was changed to P-3. The obtained organic nanopigment particle non-aqueous dispersion (pigment dispersion composition B) was subjected to the same evaluation test as in Example 1. The results are shown in Table 1.

<Example 3>
The same procedure as in Example 1 was performed except that the crosslinked polymer compound P-1 in Example 1 was changed to P-14. The obtained organic nanopigment particle non-aqueous dispersion (pigment dispersion composition C) was subjected to the same evaluation test as in Example 1. The results are shown in Table 1.

<Example 4>
The crosslinked polymer compound P-1 in Example 1 was changed to P-15, and the same operation as in Example 1 was performed. The obtained organic nanopigment particle non-aqueous dispersion (pigment dispersion composition D) was subjected to the same evaluation test as in Example 1. The results are shown in Table 1.

<Comparative Example 1>
The hydrophilic aggregates present in the organic pigment fine particle aqueous dispersion prepared by the same operation as in Example 1 were filtered using a filter (H010A047A, trade name, manufactured by Advantech), and the collected solid was filtered. For the washed and dried solid (1 part by mass) as in Example 1, as the hydrophobizing dispersant of Example 1, instead of the crosslinked polymer compound P-1, methacrylic acid / benzyl methacrylate co-polymer By combining (2 parts by mass), 1-methoxy-2-propyl acetate (8 parts by mass), and performing ultrasonic irradiation for 3 hours using an ultrasonic homogenizer US series (trade name) manufactured by Nippon Seimitsu Seisakusho Co., Ltd. An organic pigment fine particle non-aqueous dispersion (pigment dispersion composition E) using the following non-aqueous solvent as a dispersant was obtained. Evaluation was performed in the same manner as in Example 1 except that filter filtration was performed as described above. Table 1 shows the results of the same evaluation test as in Example 1 for the pigment dispersion composition E.

  As the above results show, according to the present invention, it is possible to efficiently obtain a non-aqueous dispersion of organic nanopigment particles having high dispersibility and dispersion stability with the addition of a small amount of a hydrophobizing dispersant. I was able to.

[Preparation of colored photosensitive resin composition]
The components of the writing composition were further added to 1000 parts by mass of the pigment dispersion compositions A to E obtained in Examples 1 to 4 and Comparative Example 1, and the mixture was stirred and mixed to give the colored photosensitive resin composition (color resist solution) of the present invention. ) Was prepared.

〔composition〕
-Dipentaerythritol hexaacrylate-80 parts by mass-4- [o-bromo-pN, N-di (ethoxycarbonyl) aminophenyl] -2,6-di (trichloromethyl) -S-triazine (light Polymerization initiator) ... 30 parts by mass-propylene glycol monomethyl ether acetate solution of benzyl methacrylate / methacrylic acid (= 70/30 [molar ratio]) copolymer (mass average molecular weight: 10,000) (solid content 40) %) ... 200 parts by mass, 1-methoxy-2-propylacetate ... 490 parts by mass The obtained photocurable composition (color resist solution) was made into a 100 mm x 100 mm glass substrate (1737, manufactured by Corning). ) And applied so that the x value as an index of color density is 0.650, and dried in an oven at 90 ° C. for 60 seconds ( Ribeku). Thereafter, the entire surface of the coating film was exposed at 200 mJ / cm ² (illuminance 20 mW / cm ² ), and the exposed coating film was 1% aqueous solution of alkali developer CDK-1 (manufactured by Fuji Film Electronics Materials Co., Ltd.). And rested for 60 seconds. After standing still, pure water was sprayed in a shower to wash away the developer. The coating film that has been exposed and developed as described above is heat-treated in a 220 ° C. oven for 1 hour (post-baking) to form a colored resin film for the color filter on the glass substrate. Color filter) was produced.

  Table 2 shows the results of measuring the contrast of the R component of each film obtained in the same manner as in Example 1.

[Table 2]
-----------------------------------
Colored photosensitive resin composition Contrast Notes -----------------------------------
A 17000 Example 1
B 14000 Example 2
C 15000 Example 3
D 15000 Example 4
E 11000 Comparative Example 1
-----------------------------------

  As can be seen from the above results, the color filter produced using the non-aqueous dispersion prepared using the pigment composition of the present invention and the colored photosensitive resin composition therefrom has a higher contrast than that of the comparative example. showed that.

Claims (12)

  A polymer having a number average molecular weight of 500 or more in a main chain having at least one polymer structure selected from the group consisting of polyacrylate, polymethacrylate, polystyrene, polyacrylamide, polymethacrylamide, polyvinylamide, and polyvinyl ether An organic pigment composition characterized in that a graft polymer having a chain as a side chain contains a crosslinked polymer compound bridged in the main chain and organic pigment fine particles. The organic pigment composition according to claim 1, wherein the crosslinked polymer compound has a structure having repeating units (1-1) to (1-3) represented by the following general formula (1).

_(Wherein, A _1, A 2, _{A 3,} and _{A 4} is .R ₁ to represent each independently a hydrogen atom or a methyl group carboxylic acid, sulfonic acid, phosphoric acid or heterocycle having one or more nitrogen atoms and, (P ₁ represents a polymer chain having a number average molecular weight of 500 or more forming the side chain, and L represents a divalent linking group forming a cross-linked portion.) The organic pigment composition according to claim 1 or 2, wherein the crosslinked polymer compound has a structure having repeating units (2-1) to (2-4) represented by the following general formula (2). object.

(In the formula, A _1-1 , A _1-2 , A ₂ , A ₃ , and A ₄ each independently represent a hydrogen atom or a methyl group. R ₂ represents a heterocyclic group having one or more nitrogen atoms. X represents —O—, —NH—, or —O—Y—NH—CO—Z—, Y represents an alkylene group having 1 to 4 carbon atoms, and Z represents —O— or —NH—. P ₂ represents a polymer chain forming the side chain and having a number average molecular weight of 500 or more, and L represents a divalent linking group forming a cross-linked portion.   The organic pigment composition according to any one of claims 1 to 3, wherein the polymer chain having a number average molecular weight of 500 or more is hydrophobic.   The organic pigment composition according to any one of claims 1 to 4, wherein the crosslinked polymer compound is added to a composition containing the organic pigment fine particles.   The graft polymer constituting the crosslinked polymer compound is compatible with (A) a monomer containing at least one of an acidic group and a basic group, (B) a monomer containing a nitrogen-containing heterocycle, and (C) a non-aqueous medium. And (D) a copolymer of at least one monomer selected from the group consisting of monomers having an affinity for organic pigment fine particles present in an aqueous medium and (E) a bifunctional monomer. The organic pigment composition according to any one of claims 1 to 5.   The organic pigment composition according to any one of claims 1 to 6, wherein the organic pigment fine particles have an average primary particle size of 10 to 100 nm.   8. The hydrophobic aggregate is obtained by adding the crosslinked polymer compound to the composition of the organic pigment fine particles existing as an aqueous aggregate in an aqueous medium. The organic pigment composition described in 1.   The organic pigment fine particles are build-up fine particles produced by mixing a solution of an organic pigment dissolved in a good solvent and a medium that is compatible with the good solvent and is a poor solvent for the organic pigment. The organic pigment composition according to claim 1, wherein the organic pigment composition is one.   The organic pigment composition according to claim 9, wherein the hydrophobic pigment is contained in a non-aqueous medium, and the aggregate is dissolved and redispersed.   A colored photosensitive resin composition comprising at least the organic pigment composition according to claim 10, a binder, a monomer or an oligomer, and a photopolymerization initiator or a photopolymerization initiator system.   A color filter produced using the colored photosensitive resin composition according to claim 11.