JP4621528B2 - Soluble pigment precursor and method for producing organic pigment - Google Patents

Description

  The present invention relates to a soluble pigment precursor, a method for producing an organic pigment, and a color display device, and more particularly to a method for producing a pigment compound, which is a compound useful as a coloring material.

  Colors of solid-state imaging devices such as liquid crystal display devices such as liquid crystal displays (LCD) typified by notebook computers and liquid crystal televisions, and charge coupled devices (CCD) used as input devices for digital cameras and color copiers Color filters are required for conversion. As a method for producing color filters used in these liquid crystal display devices and solid-state image sensors, a pigment dispersion method is currently the mainstream.

  The pigment dispersion method is a method for producing a color filter by a photolithography method using a colored photosensitive composition in which a pigment is uniformly dispersed in a photosensitive resin composition. Since this method uses a pigment, it has heat resistance and light resistance, and since it is patterned by a photolithography method, it has a sufficient positional accuracy and is suitable for manufacturing a color filter for a large-screen, high-definition color display. However, pigments have insufficient spectral characteristics and color purity compared to dyes, and pigments are difficult to adjust in hue compared to dyes that can spectrally adjust all colors, and there is a rough feeling of pixels. is there.

  As a method for solving these problems, a dye whose color has been adjusted is used, and a tert-alkoxycarbonyl group is bonded to quinacridone or phthalocyanine as a precursor for producing a pigment having a particle size that can be converted into a pigment form later. Patent Document 1, Patent Document 2, and Patent Document 3 propose a method of patent pigment that generates a pigment by deprotection using acid or heat. However, in the method of the latent pigment bonded with these tert-alkoxycarbonyl groups, it is difficult to control the growth of the pigment because of deprotection using acid or heat, resulting in stable hue and light fastness. It was not possible to avoid the problem that it was difficult to produce a colored product having s.

In order to solve such problems, a phthalocyanine compound having an improved solubility group is disclosed in Patent Document 4, but it is still difficult to provide a stable hue because it is a method of generating a color image by heat. is there.
Japanese translation of PCT publication No. 2002-533549 European Patent No. 761772 International Publication WO 98/32802 Pamphlet (Japanese Patent Publication No. 2001-513119) International Publication WO 00/17275 Pamphlet (Japanese Patent Publication No. 2002-526589)

  An object of this invention is to provide the soluble pigment precursor which can manufacture the pigment which was able to express the hue stably designed beforehand.

As a result of intensive studies, the present inventors have been able to stably express a predesigned hue by light irradiation or chemical treatment by introducing a soluble pyrithione derivative into a coloring compound. I found out. The present invention has been made based on this finding. The means for solving the problems related to the present invention will be described below.
(1) The pigment is decomposed by light irradiation or chemical treatment to release a radical represented by the general formula (Ia) and / or a radical represented by the general formula (Ib) which is an isomer thereof, and a pigment A soluble pigment precursor represented by the general formula (II), characterized in that

In the general formulas (Ia) and (Ib), Q represents a group that forms a nitrogen-containing heterocycle which may have a substituent.

In general formula (II), La represents a bivalent coupling group. l represents 0 or 1; X represents a group represented by the general formula (III). m represents an integer of 1 to 8. When m is 2 or more, a plurality of [(La) ₁ -X] may be the same or different. D represents a group containing a pigment chromophore.

In the general formula (III), Q represents a group that forms a nitrogen-containing heterocycle optionally having a substituent,
(2) The radicals represented by the general formula (Ia) and the general formula (Ib) are represented by the general formulas (IV-a) and (IV-b) or the general formula (Va), respectively. And the soluble pigment precursor according to item (1), which is a radical of a nitrogen-containing heterocyclic compound represented by (Vb),

In the general formulas (IV-a), (IV-b), (Va) and (Vb), V represents a substituent. h represents an integer of 0 to 4 (provided that (Va) and (Vb) represent an integer of 0 to 2). When h is 2 or more, a plurality of Vs may be a substituent that forms a ring structure.
(3) The soluble pigment precursor according to (1), which is a diketopyrrolopyrrole compound represented by the general formula (VI):
Formula (VI)

In general formula (VI), La represents -CO-. X represents a group represented by the general formula (III). n represents an integer of 1 to 2. When n is 2, a plurality of [(La) -X] may be the same or different,
(4) A method for producing an organic pigment, wherein the soluble pigment precursor according to any one of (1) to (3) is subjected to a heat treatment, and
(5) A method for producing an organic pigment, which comprises irradiating the soluble pigment precursor according to any one of (1) to (3) with light having a wavelength of 230 nm to 500 nm,
Is to provide.

  In the present invention, “soluble” means that the amount of solvent required to dissolve 1.0 g of the pigment precursor at 20 ± 5 ° C. using water or an organic solvent alone or a mixed solvent of two or more types is less than 1000 mL Refers to the nature of the compound that is.

  According to the present invention, it is possible to stably produce a hue designed in advance by heat or light irradiation, and it is possible to create a pigment that can be used in a color display device.

Hereinafter, the present invention will be described in detail.
The soluble pigment precursor represented by the general formula (II) of the present invention is decomposed by heat or light irradiation, and is represented by the general formula (I) which is a radical represented by the general formula (Ia) and / or an isomer thereof. The radical represented by -b) is released to form a pigment.

In the general formulas (Ia) and (Ib), Q represents a group that forms a nitrogen-containing heterocycle that may have a substituent.

In general formula (II), La represents a divalent linking group. l represents 0 or 1; X represents a group represented by the general formula (III). m represents an integer of 1 to 8. When m is 2 or more, a plurality of [(La) _l -X] may be the same or different. D represents a pigment chromophore.

In general formula (III), Q represents a group that forms a nitrogen-containing heterocycle that may have a substituent.

Next, the compounds represented by formulas (Ia) and (Ib) in the present invention will be described.
The radicals represented by the general formulas (Ia) and (Ib) are preferably represented by the general formulas (IV-a) and (IV-b) or (Va) and (Vb), respectively. And a radical of a mercaptopyridine represented by the general formulas (VII-a) and (VII-b), respectively.

In the general formulas (IV-a), (IV-b), (Va) and (Vb), V represents a substituent. h represents an integer of 0 to 4 (provided that (Va) and (Vb) represent an integer of 0 to 2). When h is 2 or more, a plurality of Vs may be a substituent that forms a ring structure.

In general formulas (VII-a) and (VII-b), V represents a hydrogen atom or a substituent containing a sulfo group or a C _{1 to} C ₂₀ linear or branched alkyl group. Since V is a solubility-imparting part of the coloring compound, various solubilitys can be imparted by the substituent. Preferably, groups which are suitable for the purpose of solubilization as described in JP-T-2002-533549, a linear or branched alkoxy group sulfo group, or a _C 1 _{-C 20,.} When V is a sulfo group, it is preferable to form a counter ion represented by —SO ₃ M ¹ . M ¹ is particularly preferably a +1 to +3 valent cationic group, and preferably a +1 to +3 valent cationic group, preferably a proton, an ammonium group, an alkylammonium group, an alkylphosphonium group, an arylphosphonium group, an alkylsulfonium group Group, arylsulfonium group, alkylsilyl group, metal ion. More preferred are proton, ammonium group, alkylammonium group and alkali metal, and most preferred are proton, alkylammonium group, lithium, potassium and sodium.

In the present invention, the radicals represented by the general formulas (Ia) and (Ib), preferably the radicals of mercaptopyridinesulfonic acid represented by the general formulas (VII-a) and (VII-b), The soluble pigment precursor represented by the formula (II) is decomposed and released by heat or light irradiation, and the remaining compound becomes a pigment (dye). The soluble pigment precursor represented by the general formula (II) is preferably a colored compound represented by the following general formula (VIII).
Formula (VIII)
D-[(T) _z- (L) _l -X] _m

In the general formula (VIII), D is a quinacridone, anthraquinone, perylene, indigo, quinophthalone, indanthrone, isoindolinone, isoindoline, dioxazine, azo, phthalocyanine, or diketopyrrolopyrrole series chromophore residue or organic dye. And the residue is bonded to m X's by meeting T and / or L with one or more carbon atoms or a heteroatom selected from the group consisting of N, O and S. L is a straight-chain or branched alkylene group having 1 to 6 carbon atoms, -CO-, or ^- represents a ^{- (CR 1 R 2 CR 3} R 4 O-) linkage group consisting of n-. R ¹ , R ² , R ³ and R ⁴ are any of a hydrogen atom, a methyl group, an ethyl group, a phenyl group and a halogen atom, and R ¹ , R ² , R ³ and R ⁴ may be the same It may be different. n represents an integer of 0 to 20. l represents 0 or 1; T is _{-SO 2 -, - CO -,} - SO 2 NR 5 -, or -CONR ⁵ - represents a. R ⁵ represents a hydrogen atom, a methyl group, or —L—X. z represents 0 or 1; X represents a group represented by the general formula (III) or a hydrogen atom. However, z and l are not 0 at the same time. Nitrogen atoms bonded to T are quinacridone-, anthraquinone-, perylene-, indigo-, quinophthalone-, indanthrone-, isoindolinone-, isoindoline-, dioxazine-, azo-, phthalocyanine- or diketopyrrolopyrrole system. This is a part constituting the chromophore residue.

  The group represented by the general formula (III) is preferably a group represented by the general formula (IX).

In the formula, V represents a hydrogen atom or a substituent containing a sulfo group or a C _{1 to} C ₂₀ linear or branched alkyl group.

When D is a pigment precursor, a known chromophore residue having a basic structure of D (H) _m can be used, and examples thereof include compounds represented by the following formulas and derivatives thereof.

  Although the preferable specific example of a compound represented with general formula (II) below is shown, this invention is not limited to these. In the following compounds, T, L, X, z, and l are the same as defined in the general formula (VIII).

  Perylenecarboximide represented by the following formula.

  Quinacridone represented by the following formula.

In the formula, R ⁵ and R ⁶ each independently represent a hydrogen atom, a halogen atom, a C ₁ -C ₂₄ alkyl group, a C ₁ -C ₆ alkoxy group or a phenyl group. A represents [(T) _z- (L) _l -X].

  Quinacridone quinone represented by the following formula.

In the formula, R ⁵ and R ⁶ each independently represent a hydrogen atom, a halogen atom, a C ₁ -C ₂₄ alkyl group, a C ₁ -C ₆ alkoxy group or a phenyl group. A represents [(T) _z- (L) _l -X].

  Quinophthalone represented by the following formula.

In the formula, R ⁷ represents a hydrogen atom or OA. R ⁸ to R ¹¹ each independently represents a hydrogen atom, a halogen atom, —COO—C ₁ -C ₅ alkyl or —CONA—C ₁ -C ₆ alkyl. A represents [(T) _z- (L) _l -X].

  Dioxazine represented by the following formula.

^{Wherein, R 12} represents a hydrogen atom or an alkyl group having a halogen atom or a _C 1 _{-C 24.} R ¹³ and R ¹⁴ each independently represent a hydrogen atom, a halogen atom, a C ₁ -C ₄ alkyl group, a C ₁ -C ₄ alkoxy group, a NACOC ₁ -C ₄ alkyl group, a NACO phenyl group, or NH-A. , Having at least one NACOC ₁ -C ₄ alkyl group, NACO phenyl group, or NH-A. A represents [(T) _z- (L) _l -X].

  Isoindoline represented by the following formula.

Where R ¹⁵ is

R ¹⁶ is a hydrogen atom or a C ₁ -C ₂₄ alkyl group, benzyl group or

R ¹⁷ represents a hydrogen atom, A, or R ¹⁵ , and R ^{18 to} R ²¹ each independently represents a hydrogen atom, a C _{1 to} C ₂₄ alkyl group, or a C _{1 to} C ₆ An alkoxy group, a halogen atom or a trifluoromethyl group is represented. A represents [(T) _z- (L) _l -X].

  Isoindolinone represented by the following formula.

In the formula, R ²² and R ²³ each independently represent a hydrogen atom, a halogen atom, or a C ₁ -C ₆ alkyl group. A represents [(T) _z- (L) _l -X].

  A benzimidazolone azo compound represented by the following formula.

In the formula, R ^{24 to} R ²⁶ are each independently a hydrogen atom, a halogen atom, a C _{1 to} C ₆ alkoxy group, a C _{1 to} C ₆ alkyl group, a trifluoromethyl group, a nitro group, an acetyl group, or CON (R ²⁷ ) _2. Or represents SO ₂ N (R ²⁷ ) ₂ . R ²⁷ represents a hydrogen atom a halogen _atom, C 1 -C ₆ alkyl group or a substituted or unsubstituted phenyl group. A represents [(T) _z- (L) _l -X].

  An indigo compound represented by the following formula.

^{Wherein, R 28} represents a hydrogen atom, a cyano _group, C 1 -C ₆ alkyl _group, C 1 -C ₆ alkoxy group or a halogen atom. A represents [(T) _z- (L) _l -X].

Anthraquinone, perylene, quinophthalone, indanthrone, azo, phthalocyanine, or diketopyrrolopyrrole compound having [(T) _z- (L) ₁ -X] is also preferable. Of these, phthalocyanine or diketopyrrolopyrrole compounds are preferred. Specific examples of phthalocyanines having [(T) _z- (L) ₁ -X] are shown below.

  Next, although the preferable specific example of a compound represented by general formula (IV) is shown, this invention is not limited to these.

In the present invention, by adding a pyrithione compound to a colored compound, the colored compound is made soluble, and the decomposition of pyrithione triggered by heating or irradiation of light makes the colored compound insoluble and enables the formation of a pigment. To. Preferably it is by heat processing, The temperature in that case is 30 to 100 degreeC, More preferably, it is 50 to 80 degreeC. In making this unnecessary, it is preferably carried out in the presence of an amine or a thiol compound, and a thiol compound is particularly preferred. Preferred thiol compounds are linear or branched C _{4 to} C ₁₂ mercaptans, optionally substituted thiophenol, mercaptoethanol, and dithiothreitol.

In addition, the present invention makes it possible to form a pigment by insolubilizing a colored compound by decomposition of pyrithione triggered by light irradiation. The light is preferably light having a wavelength of 230 nm to 500 nm. The light irradiation amount is preferably 0.1 mJ / cm ^{2 to} 10 J / cm ² .

  It is known that pyrithione compounds generate radicals by cutting N—O bonds with a very high quantum yield upon irradiation with near ultraviolet rays. This phenomenon is described, for example, in `` Journal of the American Chemical Society '', 1996, 118, p. 10113, `` Journal of the American Chemical Society ''. the American Chemical Society), 1997, p.6457.

The N-radical of mercaptopyridine generated by decomposition is converted into an S-radical by isomerization, and this is converted into a stable compound by bonding of S-radicals or proton extraction from a solvent species or a nearby compound. . In addition, the O-radical combined with the coloring compound generated by the decomposition generates a carbon radical obtained by O-radical state or 1,2-shift or 1,5-shift of the radical, and then draws protons. Or it changes to the state which lost the solubility by recombination with a radical seed | species. Further, when the O-radical is a carboxy group or a carbamoyl group, it is decarboxylated to generate carbon and nitrogen radical species, respectively. The radical species of carbon and nitrogen can be changed into a state in which the solubility is lost by extracting a proton from the solvent or recombining with the radical species. In this way, the coloring dye main body is separated from the solubility-imparting site by the decomposition of pyrithione by light irradiation, and the hydrophilic group of the original compound is lost, so that it becomes insoluble in the solvent. The coloring compounds that have become insoluble by irradiation with light can aggregate to form fine pigments.
This principle is shown below

  According to the principle of pigment preparation according to the present invention, it is possible to give a desired hue because a soluble group is directly bonded to a colored compound. In addition, since pigmentation can be easily performed by heat or light irradiation, a pigment having a desired particle size and hue can be obtained. For example, a fine pigment having a particle size of 10 nm to 100 nm can be formed.

  According to the present invention, preferably a pre-designed hue can be stably expressed by light irradiation or chemical treatment by introducing a soluble pyrithione derivative into a coloring compound by a conventional method. it can.

  The compound represented by the general formula (Ia) or (Ib) is subjected to chemical treatment such as reductive or oxidative treatment on the soluble pigment precursor represented by the general formula (II). But it is released. As the chemical treatment, treatment with a one-electron reducing agent or radical species is preferable. The radical species may be a compound represented by the general formula (Ia) or (Ib) generated by the decomposition of the compound represented by the general formula (II). In this case, a chain of decomposition reaction can be expected.

  The use of the pigment produced from the soluble pigment precursor of the present invention is not particularly limited. For example, the pigment is added to a general positive or negative resist material by a usual pigment dispersion method and used as a resist. A predetermined pattern may be formed at the same time as the compound is cured, and color images, color filters, etc. may be formed. In addition, a pigment is prepared in the presence of a dispersant in a state soluble in water or an organic solvent, and then colored. It may be used as an agent. In the case of a hydrophilic coloring compound in which V is a sulfo group, a pigment can be obtained in an aqueous solvent, which is preferable from the viewpoint of environmental considerations.

  The organic pigment produced in the present invention is not limited in hue, and may be a magenta pigment, a yellow pigment, or a cyan pigment. Specifically, perylene, perinone, quinacridone, quinacridonequinone, anthraquinone, anthanthrone, benzimidazolone, disazo condensation, disazo, azo, indanthrone, phthalocyanine, triarylcarbonium, dioxazine, aminoanthraquinone, diketopyrrolopyrrole, thioindigo, Magenta pigments such as isoindoline, isoindolinone, pyranthrone or isoviolanthrone pigments or mixtures thereof, yellow pigments, or cyan pigments.

  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 pigments such as CI Pigment Violet 29 (C.I. No. 71129); I. Pigment orange 43 (C.I. No. 71105), or C.I. I. Perinone pigments such as CI 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 pigment, C.I. I. Pigment red 206 (C.I. No. 73900/73920), C.I. I. Pigment orange 48 (C.I. No. 73900/73920), or C.I. I. Quinacridone quinone pigments such as CI Pigment Orange 49 (C.I. No. 73900/73920); I. Anthraquinone pigments such as CI Pigment Yellow 147 (C.I. No. 60645); I. Anthanthrone 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 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 condensation 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 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 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 pigments such as C.I. Pigment Red 247 (C.I. No. 15915), C.I. I. Indanthrone pigments such as CI 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 pigments such as C.I. 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. Triarylcarbonium pigments such as CI Pigment Blue 61 (C.I. No. 42765: 1); I. Pigment violet 23 (C.I. No. 51319) or C.I. I. Dioxazine pigments such as CI Pigment Violet 37 (C.I. No. 51345); I. Aminoanthraquinone pigments such as CI 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 pigments such as C.I. Pigment Orange 73; I. Thioindigo pigments such as CI Pigment Red 88 (C.I. No. 7313), C.I. Pigment Yellow 139 (C.I. No. 56298), C.I. I. Pigment Orange 66 (C.I. No. 48210) and the like, isoindoline pigments such as C.I. I. Pigment yellow 109 (C.I. No. 56284), or C.I. Pigment Orange 61 (C.I. No. 11295) and the like, and isoindolinone pigments such as C.I. I. Pigment Orange 40 (C.I. No. 59700), or C.I. I. Pyranthrone pigments such as CI Pigment Red 216 (C.I. No. 59710), or C.I. I. It is an isoviolanthrone pigment such as CI Pigment Violet 31 (60010).

  The organic pigment must be uniformly dissolved in an alkaline or acidic aqueous medium, but whether it dissolves in acid or alkaline depends on which conditions the target pigment is easily dissolved. . 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, and disazo condensation pigments are alkaline, and phthalocyanine 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, but in the case of an inorganic base, it is preferably 1.0 to 30 molar equivalents relative to the pigment, more preferably 2. It is 0-25 molar equivalent, More preferably, it is 3-20 molar equivalent. In the case of an organic base, it is preferably 1.0 to 100 molar equivalents relative to the pigment, more preferably 5.0 to 100 molar equivalents, and even more preferably 20 to 100 molar equivalents.

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 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, and further preferably 30 to 200 molar equivalents with respect to the pigment.

  Next, the aqueous medium will be described. The aqueous medium in the present invention is water alone or a mixed solvent of water-soluble organic solvents. The addition of an organic solvent is not sufficient with water alone to dissolve the pigment and dispersant uniformly, and when water alone is insufficient to obtain the viscosity required to flow through the flow path, Although it is carried out when necessary for the formation of a stream and is not always necessary, in many cases a water-soluble organic solvent is added. Examples of the organic solvent to be added include ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, thiodiglycol, dithiodiglycol, 2-methyl-1,3-propanediol, 1,2,6-hexanetriol, and acetylene glycol derivatives. , Polyhydric alcohol solvents such as glycerin or trimethylolpropane, polyvalent alcohols such as ethylene glycol monomethyl (or ethyl) ether, diethylene glycol monomethyl (or ethyl) ether, or triethylene glycol monoethyl (or butyl) ether Lower monoalkyl ether solvent of alcohol, ethylene glycol dimethyl ether (monoglyme), diethylene glycol dimethyl ether (diglyme), or tri Polyether solvents such as tylene glycol dimethyl ether (triglyme), dimethylformamide, dimethylacetamide, 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, urea, tetramethylurea, etc. Amide solvents, sulfur-containing solvents such as sulfolane, dimethyl sulfoxide, or 3-sulfolene, polyfunctional solvents such as diacetone alcohol and diethanolamine, acetic acid, maleic acid, docosahexaenoic acid, trichloroacetic acid, or trifluoroacetic acid. Examples thereof include carboxylic acid solvents, methanesulfonic acid, and sulfonic acid solvents such as trifluorosulfonic acid. Two or more of these solvents may be mixed and used.

  A preferred organic solvent is an amide solvent or a sulfur-containing solvent in the case of alkali, a carboxylic acid solvent, a sulfur solvent or a sulfonic acid solvent in the case of acid, and more preferably a sulfur-containing solvent in the case of alkali. If it is acidic, it is a sulfonic acid solvent. Particularly preferred is dimethyl sulfoxide (DMSO) when alkaline, and methanesulfonic acid when acidic.

  The mixing ratio of water and organic solvent is a ratio that can be uniformly dissolved and is not particularly limited. Preferably, in the case of alkaline, water / organic solvent = 0.05 to 10 (mass ratio). When an inorganic acid is used in the acidic case, it is preferable to use sulfuric acid alone, for example, without using an organic solvent. When an organic acid is used, the organic acid itself is an organic solvent, and a plurality of acids are mixed or water is added in order to adjust viscosity and solubility. Preferably, water / organic solvent (organic acid) = 0.005 to 0.1 (mass ratio).

  The color filter using the organic pigment produced from the soluble pigment precursor of the present invention is an input of a liquid crystal display element such as a liquid crystal display (LCD) represented by a notebook personal computer or a liquid crystal television, a digital camera, a color copier, etc. It is suitable as a color filter provided in a color display device such as a solid-state imaging device typified by a charge coupled device (CCD) used as a device.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail based on an Example, this invention is not limited to these.

Example 1
Synthesis of compound A1

Under a yellow light, diketopyrrolopyrrole (288 mg) was dispersed in 10 mL of tetrahydrofuran, to which 366 mg of 4-dimethylaminopyridine and 760 mg of 1-oxa-2-oxo-3-thiaindolidinium chloride were added, and protected from light. Stir at 25 ° C. for 18 hours. A part of the solution after the reaction was taken and confirmed under a fluorescent lamp. The reaction solution was filtered under a yellow light to obtain Compound A1. Using a Vager-DE PRO manufactured by Applied Biosystem, the mass spectrum was measured by the MALDI method and found to be 442 (M + H ⁺ ).

Example 2
When 150 mg of dithiothreitol was added to the solution obtained in Example 1 and heated at 60 ° C., the color of the solution changed from yellowish green to orange, confirming the formation of an insoluble substance. The produced precipitate was collected using a centrifuge, dispersed again with acetone and washed to obtain a pigment. The mass spectrum of this product was 289 (M + H ⁺ ) as measured by MALDI method using Vager-DE PRO manufactured by Applied Biosystem. Thus, an insoluble pigment can be easily produced from a soluble pigment precursor to which a pyrithione compound is bound.

Claims (3)

It is decomposed by light irradiation or chemical treatment to release a radical represented by the general formula (VII-a) and / or a radical represented by the general formula (VII-b) to form a pigment. A soluble pigment precursor represented by the general formula (VI) .

In the general formula (VII-a) and the general formula (VII-b), V represents a sulfo _group, a linear or branched alkoxy group having C 1 _{-C 20.}
Formula (VI)

In general formula (VI), La represents -CO-. X represents a group represented by the general formula (IX). n represents an integer of 1 to 2. When n is 2, a plurality of [(La) -X] may be the same or different.

In General Formula (IX), V represents a hydrogen atom, a sulfo group, or a C _{1 to} C ₂₀ linear or branched alkoxy group. A method for producing an organic pigment, comprising subjecting the soluble pigment precursor according to claim 1 to a heat treatment. A method for producing an organic pigment, comprising irradiating the soluble pigment precursor according to claim 1 with light having a wavelength of 230 nm to 500 nm.