TW201905104A - Coloring composition containing xanthene dye, colorant for color filter and color filter - Google Patents

Abstract

This coloring composition containing a xanthene-based dye is represented by general formula (1), and a coloring agent, which is for a color filter and contains the coloring composition containing the xanthene-based dye and having number of diffraction peaks of 0 in a range of 3 DEG-7 DEG of a diffraction angle (2[Theta]) in a powder X-ray diffraction of CuK[alpha] radiation, provides a color filter having a high display contrast ratio.

Description

Coloring composition containing dibenzopiperan dye, colorant for color filter and color filter

The present invention relates to a coloring composition containing a dibenzopiperan dye, a colorant for a color filter using the composition, and a color filter using the colorant.

There are cases where color filters are used in liquid crystal or electroluminescence (EL) display devices. The color filter is manufactured by laminating colored layers such as a dyeing method, a pigment dispersion method, a printing method, and an electrodeposition method on a light-transmitting substrate such as glass. The coloring agents used in the colored layer are roughly classified into pigments and dyes, but pigments considered to be excellent in heat resistance and light resistance are generally widely used (for example, refer to Patent Documents 1 to 3). However, pigments are generally insoluble in solvents, so they exist in the form of particles in color filters containing resins and the like. Therefore, it is known that color filters using pigments affect the transparency or color purity due to the reflection and scattering of the transmitted light on the surface of the pigment particles in the filter, and there is also a color liquid crystal display device due to the depolarization caused by the reflection The contrast ratio is reduced.

In order to improve the problem of the reduction of such a contrast ratio, a method of using only a dye as a colorant or a method of using a dye and a pigment as a colorant in combination is proposed. The dye is soluble in the solvent, so the color filter using the dye can suppress the depolarization effect and has excellent spectral characteristics compared to the case where only the pigment is used as the colorant. As dyes used for color filters, dibenzopiperan dyes and the like are known from the viewpoint of having excellent color rendering properties, heat resistance, and light resistance (for example, refer to Patent Documents 4 to 7). It is described that the use of dibenzopiperan-based dyes such as CI acid red 289 represented by the following formula (I) or CI acid red 52 represented by the following formula (II) in combination with azopyridone-based dyes is possible An excellent red hue is obtained (for example, refer to Patent Document 4). Here, C.I. means color index.

[Chem 1]

[Chem 2]

In addition, it is known that by using these dibenzopiperan dyes or their derivatives in combination with phthalocyanine dyes, it is possible to produce a blue color filter with a high contrast ratio and high color purity (for example, refer to Patent Documents) 6, 7). It is believed that the color filter used in combination with this dye and pigment forms an agglomerate by mixing the two of different colors, and immediately causes charge movement between the dye molecule excited by the light and the nearby pigment molecule, so also It has the effect of mutually inhibiting oxidation and decomposition. Compared with the color filter made by using dye alone, it can maintain color rendering and improve light resistance. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-220520 [Patent Document 2] Japanese Patent Laid-Open No. 2007-533802 [Patent Document 3] Japanese Patent Laid-Open No. 2012-12498 [Patent Document 4] Japanese Patent Japanese Patent Laid-Open No. 2002-265834 [Patent Document 5] Japanese Patent Laid-Open No. 2012-207224 [Patent Document 6] Japanese Patent Laid-Open No. 2010-254964 [Patent Document 7] Japanese Patent Laid-Open No. 2014-12814 [Non Patent Literature]

[Non-Patent Document 1] Prepared by the corporation of the Organic Synthetic Chemistry Association, "New Dye Manual", Maruzen Co., Ltd., 1970, p.426

[Problems to be solved by the invention]

However, even if the previous dibenzopiperan dyes have sufficient color rendering properties or heat resistance, they are often insufficient in solubility or dispersibility in organic solvents for color filter manufacturing. Generally, dyes such as dibenzopiperan dyes are water-soluble. As shown in formula (I), they have a positively charged nitrogen atom (= N ⁺ <) or a negatively charged group (-SO _3- ^, etc.) in the molecule. Therefore, it is easy to hydrogen bond with water molecules (H ₂ O) which are polar molecules. However, molecules with a plurality of polar groups, such as dibenzopiperan dyes, have an intermolecular force (vandeval force, hydrogen bond, ionic bond, etc.) by molecules acting on the same or different substituents Relatively strong bonds are formed, thereby forming aggregates in a few to tens of units. If the agglomerates of the dye molecules are directly left to some extent, uneven coating will occur during film formation, and the light resistance or heat resistance will be reduced. Also, the depolarization of the transmitted light of the pigment will be complicated as The color rendering of the color filter is further reduced.

In the case where organic pigments or organic dyes are difficult to dissolve in solvents, the following method is generally used: physical milling using a machine such as a bead mill to prepare particles with a particle size of aggregates of pigments or dyes to about tens of nm However, in order to stably maintain the dispersed state of the fine particles in the solvent, additives such as surfactants are necessary. In the case of unstable dispersion, the particles may re-agglomerate and the dispersion may gel. Therefore, as the properties required for the dibenzopiperan dyes used in the manufacture of color filters, it is necessary to develop a preparation method that easily dissolves or disperses uniformly in a solvent without unnecessary additives.

The present invention was made to solve the above-mentioned problems, and its object is to provide a coloring composition, a colorant for a color filter containing the coloring composition, and the color rendering properties (brightness, contrast) of the colorant for the color filter Ratio, etc.) an excellent color filter in which the coloring composition contains a dibenzopiperan dye excellent in hue adjustment as a colorant for color filters, and the dibenzopiperan dye is used in color filters In the manufacturing process of the optical device, it has a state of solid (powder, etc.) necessary for showing good solubility or dispersibility. [Technical means to solve the problem]

The present inventors found that the best preparation method of the powder of the dibenzopiperan dye used in the manufacture of color filters, and further found that the characteristics of the solid powder can be analyzed by powder X-ray diffraction, and found that A color filter excellent in color rendering (contrast ratio) can be obtained using such a coloring composition containing a dibenzopiperan dye, and the present invention has been completed.

That is, the present invention has obtained the results of diligent research to achieve the above-mentioned object, and has the following as the gist.

1. A coloring composition, which contains a dibenzopiperan dye represented by the following general formula (1), and contains at least one CuKα ray diffraction angle (2θ) 3 under powder X-ray diffraction The number of diffraction peaks in the range of ° to 7 ° is 0 dibenzopiperan dyes.

[Chemical 3]

[In the formula, R ¹ to R ⁴ each independently represent a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, or a ring having 3 to 20 carbon atoms which may have a substituent. Alkyl groups, R ⁵ to R ⁷ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, and a carbon atom which may have a substituent Cycloalkyl having 3-20 carbon atoms, linear or branched alkoxy groups having 1-20 carbon atoms which may have substituents, cyclic alkoxy groups having 3-20 carbon atoms which may have substituents, Or a linear or branched alkenyl group having 2 to 20 carbon atoms which may have a substituent, R ⁵ and R ⁶ may also be bonded to each other to form a ring; M represents an alkali metal atom].

2. A coloring composition, wherein in the above general formula (1), R ¹ to R ⁴ are linear or branched alkyl groups having 1 to 10 carbon atoms which may have a substituent.

3. A coloring composition containing two or more dibenzopiperan dyes represented by the above general formula (1), and the smallest of the weight concentration ratios in the whole dibenzopiperan dyes The weight concentration ratio of one kind of dibenzopiperan-based dye is 0.1 to 50% by weight.

4. A colorant for a color filter, which contains the above-mentioned coloring composition.

5. A color filter using the colorant for the color filter. [Effect of invention]

The color filter produced by using the colorant for color filters containing the coloring composition containing the dibenzopiperan dye of the present invention is excellent in color rendering properties such as contrast ratio, and the dibenzopiperan dye of the present invention It is more useful as a colorant for color filters.

Hereinafter, embodiments of the present invention will be described in detail. In addition, the present invention is not limited to the following embodiments, and can be implemented with various changes within the scope of the gist thereof. First, the dibenzopiperan dye represented by the general formula (1) will be described.

In the general formula (1), the "straight-chain or branched-chain alkyl group having 1 to 20 carbon atoms which may have a substituent" represented by R ¹ to R ⁴ specifically includes: Straight-chain alkyl groups such as alkyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl; isopropyl, isobutyl, second butyl, third Branched alkyl groups such as butyl and isooctyl.

In the general formula (1), the "cycloalkyl group having 3 to 20 carbon atoms which may have a substituent" represented by R ¹ to R ⁴ specifically includes cyclopropyl, cyclopentyl, Cycloalkyl groups such as cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, and cyclodecyl.

In the general formula (1), as the "substituent group" in the "straight-chain or branched alkyl group having 1 to 20 carbon atoms having substituents" represented by R ¹ to R ⁴ , specifically include: a halogen atom such as fluorine atom, chlorine atom, bromine atom, iodine atom; -SO ₃ ^-; carbon atoms, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, etc. the 3 to 19 Cycloalkyl; methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy and other carbon atoms 1 to 19 Straight-chain alkoxy; isopropyloxy, isobutoxy, second butoxy, third butoxy, isooctyloxy, etc. branched chain alkoxy with 3 to 19 carbon atoms ; Cyclopropoxy, cyclobutoxy, cyclopentyloxy, cyclohexyloxy and other cycloalkoxy groups with 3 to 19 carbon atoms; phenyl, naphthyl, biphenyl, anthryl, phenanthryl, pyrene Aromatic hydrocarbon groups with 6 to 19 carbon atoms or condensed polycyclic aromatic groups such as pyridyl, pyridinyl, triazinyl, pyrrolyl, imidazolyl, pyrazolyl , Triazolyl, quinolinyl, isoquinolinyl, Pyridinyl, indolyl, benzimidazolyl, carbazolyl, carolinyl, acridinyl, morpholinyl, furanyl, benzofuranyl, dibenzofuranyl, thienyl, benzothienyl, Heterocyclic groups having 2 to 19 carbon atoms such as dibenzothienyl, oxazolyl, benzoxazolyl, thiazolyl, benzothiazolyl and the like. These "substituents" may include only one kind or plural kinds. When plural kinds are included, they may be the same or different from each other. Furthermore, these "substituents" may further have the substituents exemplified above.

In the general formula (1), the "substituent" in the "cycloalkyl having 3 to 20 carbon atoms having a substituent" represented by R ¹ to R ⁴ may be specifically a fluorine atom, a halogen atom a chlorine atom, a bromine atom, an iodine atom; -SO ₃ ^-; methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, carbon atoms such as 1 ～ 14 linear alkyl groups; isopropyl, isobutyl, second butyl, third butyl, isooctyl and other branched chain alkyl groups with 3 to 14 carbon atoms; cyclopropyl, Cycloalkyl, cyclopentyl, cyclohexyl, cyclooctyl and other cycloalkyl groups with 3 to 14 carbon atoms; methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, Linear alkoxy groups with 1 to 14 carbon atoms such as heptoxy, octoxy, nonoxy, decoxy, etc .; isopropoxy, isobutoxy, second butoxy, third butoxy Oxygen, isooctyloxy and other branched chain alkoxy groups with 3 to 14 carbon atoms; cyclopropoxy, cyclobutoxy, cyclopentyloxy, cyclohexyloxy and other carbon atoms with 3 to 14 carbon atoms Cycloalkoxy; phenyl, naphthyl, biphenyl, anthracenyl, phenanthrenyl, C6-C14 aromatic hydrocarbon groups or condensed polycyclic aromatic groups such as indenyl and fluorenyl; pyridyl, pyrimidinyl, triazinyl, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, quinoline Group, isoquinolinyl, naphthyridyl, indolyl, benzimidazolyl, carbazolyl, carolinyl, acridinyl, morpholinyl, furanyl, benzofuranyl, dibenzofuranyl, Heterocyclic groups having 2 to 14 carbon atoms, such as thienyl, benzothienyl, dibenzothienyl, oxazolyl, benzothiazolyl, thiazolyl, and benzothiazolyl, etc. These "substituents" may include only one kind or plural kinds. When plural kinds are included, they may be the same or different from each other. Furthermore, these "substituents" may further have the substituents exemplified above.

In the general formula (1), examples of the "halogen atom" represented by R ⁵ to R ⁷ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. The "halogen atom" is preferably a fluorine atom or a chlorine atom.

In the general formula (1), as R ⁵ to R ⁷ "straight-chain or branched alkyl group having 1 to 20 carbon atoms which may have a substituent", "carbon atoms which may have a substituent""Cycloalkyl group having 3 to 20 carbon atoms", "Straight or branched alkoxy group having 1 to 20 carbon atoms which may have a substituent", "Ring of 3 to 20 carbon atoms which may have a substituent""Alkoxygroup" or "straight-chain or branched alkenyl group having 2 to 20 carbon atoms which may have a substituent""straight-chain or branched alkyl group having 1 to 20 carbon atoms" , "Cycloalkyl having 3 to 20 carbon atoms", "Straight chain or branched alkoxy having 1 to 20 carbon atoms", "Cycloalkoxy having 3 to 20 carbon atoms" or " Straight-chain or branched alkenyl having 2 to 20 carbon atoms ", specifically, methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl Straight-chain alkyl groups such as alkyl and decyl; branched-chain alkyl groups such as isopropyl, isobutyl, second butyl, third butyl, and isooctyl; cyclopropyl, cyclopentyl, cyclic Rings such as hexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, etc. Alkyl groups; linear alkoxy groups such as methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, heptyloxy, octyloxy, nonyloxy, decyloxy, etc. ; Isopropoxy, isobutoxy, second butoxy, third butoxy, isooctyloxy and other branched chain alkoxy; cyclopropoxy, cyclobutoxy, cyclopentyloxy , Cyclohexyloxy and other cycloalkoxy; vinyl, 1-propenyl, allyl, 1-butenyl, 2-butenyl, 1-pentenyl, 1-hexenyl, isopropenyl Group, isobutenyl group, or a plurality of straight-chain or branched-chain alkenyl groups formed by bonding such alkenyl groups.

In the general formula (1), the "straight-chain or branched-chain alkyl group having 1 to 20 carbon atoms with substituents" and "3 carbon atoms with substituents" represented by R ⁵ to R ⁷ "~ 20 cycloalkyl group", "Straight or branched alkoxy group having 1 to 20 carbon atoms with substituents", "Cycloalkoxy group having 3 to 20 carbon atoms with substituents" Or "substituent" in "straight-chain or branched alkenyl group having 2 to 20 carbon atoms having a substituent", specifically, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. a halogen atom; -SO ₃ ^-; cycloalkyl group having 3 to 17 of cyclopropyl, cyclopentyl, cyclohexyl, and cyclooctyl carbon atoms; methoxy, ethoxy, propoxy, butoxy, Linear alkoxy groups with 1 to 17 carbon atoms, such as pentoxy, hexoxy, heptoxy, octoxy, nonoxy, and decoxy; isopropoxy, isobutoxy, and Branched-chain alkoxy groups with 1 to 17 carbon atoms such as dibutoxy, third butoxy, isooctyloxy; cyclopropoxy, cyclobutoxy, cyclopentyloxy, cyclohexyloxy Equivalent cycloalkoxy group with 3 to 17 carbon atoms; benzene , An aromatic hydrocarbon group or a C 1-8 carbon atoms, naphthyl, biphenyl, anthryl group having 6 to 18 6 to 17 of the condensed polycyclic aromatic group and the like. These "substituents" may include only one kind or plural kinds. When plural kinds are included, they may be the same or different from each other. Furthermore, these "substituents" may further have the substituents exemplified above.

In the general formula (1), R ¹ to R ^{4 are} preferably a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent, and 5 carbon atoms which may have a substituent The cycloalkyl group of ~ 12 is more preferably a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent.

In the general formula (1), the combination of R ¹ and R ² and the combination of R ³ and R ⁴ may be the same or different.

In the general formula (1), R ⁵ to R ^{7 are} preferably a hydrogen atom, a halogen atom, a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, or may have The linear or branched alkoxy group having 1 to 20 carbon atoms in the substituent is more preferably a hydrogen atom.

In the general formula (1), R ⁵ and R ⁶ may be bonded to each other to form a ring. The ring formed in this case is preferably a 5-membered ring or a 6-membered ring, and more preferably a 6-membered ring.

In the general formula (1), "M" represents an alkali metal atom, preferably a lithium atom, a sodium atom or a potassium atom, more preferably a lithium atom or a sodium atom, and particularly preferably a sodium atom.

The dibenzopiperan dye represented by the general formula (1) can be synthesized by a known method (see Non-Patent Document 1 etc.), for example, as follows. Sulfuraldehyde derivatives with equivalent substituents such as benzaldehyde-2,6-disulfonic acid sodium, and hydroxyaniline derivatives with equivalent substituents such as diethylaminophenol in acid aqueous solution such as sulfuric acid The condensation reaction is performed under appropriate heating conditions to obtain an intermediate represented by the following general formula (2). Then, by dehydrating the following general formula (2), an intermediate represented by the following general formula (3) can be obtained. Further by the following general formula (3) in an acid aqueous solution under appropriate heating conditions of the reaction with the iron (III) (FeCl ₃₎ chlorination and oxidation using sodium hydroxide (NaOH) aqueous alkali solution, etc. After neutralization, salting-out is performed using chlorides such as sodium chloride (NaCl) to obtain a product containing the compound represented by general formula (1).

[Chem 4]

[Chemical 5]

[化 6]

In the above general formulas (2) and (3), R ¹ to R ⁷ represent the same definitions as in the general formula (1).

In the synthesis method of the dibenzopiperan dye represented by the general formula (1), when the precipitated dibenzopiperan dye adheres firmly and becomes an obstacle to stirring, in order to eliminate or alleviate this situation , You can also mix organic solvents. The mixed organic solvent is not particularly limited as long as it has sufficient solubility of the corresponding dibenzopiperan dye, and aromatic hydrocarbons such as toluene and xylene can be used alone; acetone, 2-butanone, 2- Ketones such as pentanone and 3-pentanone; esters such as ethyl acetate and butyl acetate; alcohols such as methanol, ethanol, propanol, isopropanol, butanol, amyl alcohol, and hexanol, etc., or these Mix and use.

The dibenzopiperan dye represented by the general formula (1) can be obtained by processing the product obtained by the above-mentioned synthesis method as necessary as follows: by purification by column chromatography; by silica gel, Adsorption purification of activated carbon, activated clay, etc .; known purification by dispersion washing of the solvent or recrystallization, crystallization, salting out, etc. The solvent used in these purification methods is not particularly limited, and alcohols such as water, methanol, ethanol, etc .; halogenated methanes such as dichloromethane and chloroform; toluene, etc., or these may be used in combination.

As the dibenzopiperan dye of the present invention represented by the general formula (1), commercially available products can be used. Specifically, dibenzopiperan dyes such as C.I. Acid Red 52 or compositions containing these dyes as main components are commercially available. These can also be used directly to prepare the coloring composition of the present invention, and the coloring composition of the present invention can be prepared using the same method as the above-mentioned method for refining dibenzopiperan dyes.

Specific examples of preferred compounds of the dibenzopiperan dye of the present invention represented by the general formula (1) are shown in the following formulas (A-1) to (A-10), but the present invention is not limited to this And other compounds. In the following structural formula, a part of hydrogen atoms may be omitted. Moreover, even in the case of the presence of stereoisomers, the planar structural formula is also described.

[化 7]

[Chem 8]

[化 9]

[化 10]

[化 11]

[Chem 12]

[Chem 13]

[化 14]

[化 15]

[Chem 16]

The dibenzopiperan dye represented by the general formula (1) of the present invention may be used alone or in combination of two or more of different molecular structures (for example, mixed). The weight concentration ratio of the smallest dibenzopiperan dye is 0.1-50% by weight. That is, of the two or more dibenzopiperan dyes, the smallest amount of one dibenzopiperan dye accounts for 0.1 to 50% by weight of the two or more dibenzopiperan dyes as a whole. The type of the dibenzopiperan dye is preferably one or two types.

Hereinafter, the coloring composition containing at least one dibenzopiperan dye represented by the general formula (1) of the present invention will be described in detail.

The coloring composition containing the dibenzopiperan dye of the present invention may be a synthetic dye or a commercially available dye, and has a state suitable as a powder for a color filter. Specific examples of the method for preparing the powder of the coloring composition containing the dibenzopiperan dye of the present invention are shown below. As a method of changing the state of the powder to obtain a suitable coloring composition powder, there can be mentioned: (a) a method of obtaining a powder by changing the drying conditions (speed, temperature, air pressure) of the dye solution; (b) a method of making the dye solution Method for obtaining crystals or agglomerates by changing the state (type of solvent, mixed solvent, pH value, etc.); (c) In powder, make solvent molecules, water, or other dibenzopiperan dyes of the present invention The method of mixing and drying the ingredients; (d) A method that is suitable for selection or repetition of the drying methods of (a) to (c); (e) Heat treatment of the dried powder from the outside to change the state of the powder The method; (f) The method of heating the powder in a vacuum to sublime it, and recrystallization (sublimation purification); (g) The method of physically applying force (pressurization) to the powder to change the state of the powder ; And (h) a method of separating (grading) from a state in which a plurality of powders are mixed, etc., may be any method, and it is preferable to select several of the above methods to obtain powder.

Powders containing dibenzopiperan dyes obtained by synthesis, or commercially available dibenzopiperan dyes include solvent molecules, moisture, molecular structure components other than the dibenzopiperan dyes of the present invention, and others ingredient. Either of these powders can be used directly, but it is preferable to carry out a refining treatment. However, even with any purification method, there may be a certain ratio of impurities, but as long as it is a dye that can be manufactured or obtained at the current technical level, it can be used.

However, the coloring composition of the present invention is set so that it can also contain at least one dibenzopiperan dye represented by the general formula (1) as a main component in the component of its solid content, and contains a certain concentration range Moisture or other solvent molecules. The industry believes that the presence of moisture in the coloring composition can be considered as one of the factors that change the crystal structure of the powder of the dibenzopiperan dye. As a result, the The solubility changes. For example, by adjusting the weight ratio (water content (% by weight)) of water in the total weight of the coloring composition containing the dibenzopiperan dye, the solubility in organic solvents such as PGME can be obtained while maintaining heat resistance Higher coloring composition. The water content in the coloring composition can be arbitrarily adjusted within the range of 0.1 to 20% by weight.

As a method for preparing the coloring composition containing the dibenzopiperan dye of the present invention, among the methods related to the above (a) to (d), for example, there are the following methods. In a container of appropriate size, put the powder containing dibenzopiperan dye as the main component, activated carbon, and solvent and mix, heat, and stir for a certain period of time. After stirring, hot filtration was performed to obtain a filtrate. The filtrate is concentrated under an atmospheric pressure or reduced pressure while being concentrated at an appropriate solvent evaporation rate to obtain a concentrate. The coloring composition containing the solvent and the like as a concentrate is extracted from the container, and dried in another container. Furthermore, the solvent was removed by drying under reduced pressure at a certain temperature. In this way, a coloring composition containing at least one dibenzopiperan dye represented by the general formula (1) is obtained.

Or, as long as the solid (powder) is obtained, it may be any method. For example, after mixing the dibenzopiperan dye in the solvent as described above, an appropriate acid or alkali is added to cause the pH value to occur. After changing and precipitating crystals, the precipitate is dried by the method described above. Furthermore, instead of acid or alkali, other solvents or solids can be mixed in the solution, and the precipitated crystals can be dried.

As described above, the dibenzopiperan dyes dissolved or dispersed in the liquid can be obtained by the following methods to obtain the coloring composition of the present invention containing dibenzopiperan dyes: the solvent is evaporated and dried; Make the speed suitable for change; precipitation in the solvent, etc.

Here, as the material of the container for stirring, an appropriate one can be selected and used, for example, a glass container such as a flask, a metal container, a resin container, a glass-lined container, or the like can be used.

The size of the container for stirring may be various sizes, preferably 1 to 5 L with respect to 100 g of the powder. However, it is not limited to this range, and can be arbitrarily determined according to the amount of solvent required to dissolve the dibenzopiperan dye used.

In the case of using activated carbon when mixing in a solvent, in order to improve the adsorption capacity of the activated carbon, it is preferably powdered or finely powdered activated carbon.

The solvent may be one kind or a mixture of plural kinds, preferably alcohol, and in the case of alcohol, preferably methanol, ethanol, propanol, isopropanol, butanol, more preferably methanol. The solvent may or may not be dehydrated.

The weight of the dibenzopiperan dye when mixed in the solvent (the total of these in two or more cases) and the solvent is preferably 3% relative to the weight of the dibenzopiperan dye. ~ 10 times the weight ratio. However, it is not limited to this range, and the amount required to dissolve the dibenzopiperan dye used can be arbitrarily determined.

As other components, in order to improve the performance of the coloring composition of the present invention as a colorant for color filters, surfactants, dispersants, defoamers, leveling agents, and other color filter colorants can be added Organic compounds such as mixed additives. However, the content rate of these additives in the coloring composition is preferably an appropriate amount, and it is preferable to reduce the solubility in the solvent of the coloring composition of the present invention, or to increase it above necessary, and it is not to affect the color filter. The content ratio of the range of effects of other same kind of additives used in the manufacture of the device. These additives can be added at any point in the preparation of the coloring composition.

The atmosphere in the container during mixing or stirring may include air, nitrogen, other inert gases, etc., and is not particularly limited. Considering the safety of ignition due to static electricity during manufacturing, it is preferable to replace the container with an inert gas such as nitrogen.

The drying of the concentrate is carried out in a container such as a dish or a tank. It is allowed to stand for 1 to 96 hours at atmospheric pressure so that the water content becomes an equilibrium state (drying once). The temperature during drying is preferably in the range of 20 ° C to 100 ° C. Here, in the case of temporary drying, it is preferable that moisture to some extent remains without being completely dried.

The coloring composition containing the dibenzopiperan-based dye once dried is further dried (secondary drying) using a dryer or the like having a venting device such as a vacuum dryer. It can also replace the vacuum dryer to air-dry on a trough-shaped container with a wide bottom area. The temperature or time during drying can be arbitrarily set in order to obtain the target color combination of the powder state, and is not particularly limited. When alcohol is used as the solvent, the time when the alcohol is removed as much as possible can be used as the drying end point. Examples of methods for measuring the drying end point include methods for the analysis and quantification of solvent components such as powder state observation, weight measurement, nuclear magnetic resonance analysis (NMR), and gas chromatography analysis (GC).

As a method for measuring the water content of the coloring composition prepared as described above, there may be mentioned: the KF method using the electric titration method or the volumetric titration method; Analytical method; heating and drying method using a heating and drying moisture meter; gas chromatography (GC) method, infrared or near infrared absorption method; nuclear magnetic resonance absorption method; electrical resistance method; dielectric constant method; distillation method; etc. In addition, the analysis of the type or amount of impurities other than moisture can also be estimated in the same way by powder state observation, weight measurement, NMR analysis, GC analysis, and the like.

As a method for preparing the coloring composition containing the dibenzopiperan dye of the present invention, among the methods corresponding to the above (e) to (h), for example, there are the following methods.

The method for preparing the coloring composition of (a) to (d) above is a wet method. In contrast, the methods of (e) to (h) below are generally for the case of further increasing the purity of the dye or maintaining it directly As a result, the dry method of changing the crystal structure in the case of the purity of the powder obtained.

Specifically, the heat treatment of (e) is generally used in a case where the crystal structure changes before and after heating from room temperature (near 25 ° C.) to the melting point of the solid (or glass transition temperature). The heating device may be of any material or form, and may be heated on a commercially available hot plate. In addition, a commercially available oven may be used, and a quartz reaction furnace may also be used. The atmosphere can also be in the air, but usually to prevent decomposition or deterioration of the sample, it is preferably nitrogen or inert gas or under reduced pressure. The heating time is appropriate.

The sublimation purification of (f) is mostly the case where the powder is heated in a vacuum to sublime it, so it is possible to remove moisture, solvent molecules, and other impurities in the solid powder as much as possible. Compared to the crystal structure. The device is not limited as long as it can be decompressed to high vacuum to ultra high vacuum. The material of the heating container into which the sample is placed can be metal or glass.

If high pressure is applied to the powder as in the method of (g) pressurization, the solid crystallization system may irreversibly change. The method of applying pressure can be compressed by air pressure, or by using a press machine such as a metal steel with higher hardness.

The classification of (h) refers to the method of separating the components in a specific state from the size, density and crystal structure of the powder obtained by the method of obtaining any of the above solid powders. The powder before separation may be crushed initially or not. When the crystals of different components stick together, there are cases where the components are easily separated by crushing. When grading by size, use a sieve and other appliances. For those with different density or weight, it is possible to use a device that scatters the powder due to air flow and separates due to the difference in flight distance, or performs centrifugal separation.

By the method described above, the coloring composition of the present invention containing at least one dibenzopiperan dye represented by the general formula (1) can be obtained in a powder state. Hereinafter, regarding the powder, a method for obtaining a powder having a state suitable for a color filter as a problem to be solved by the present invention will be described

Regarding the state of the powder of the coloring composition of the present invention, its shape can be observed using an optical microscope, a scanning electron microscope (SEM), or the like. The shape of the coloring composition of the present invention can generally be used in the form of solid powder having a crystalline, microcrystalline, micropowder, flake, needle crystal, granular, etc. shape, but is not particularly limited.

By measuring the particle size distribution, surface area, pore size distribution, powder density, etc. of the powder of the coloring composition of the present invention, the overall and average information of the shape of the powder can be obtained in more detail. For example, the Coulter method for measuring the resistance of an electrolyte in which powder is dispersed, the centrifugal sedimentation method for obtaining the Stokes effective diameter by measuring the absorbance of a dispersion in powder, and the dispersion in powder The laser diffraction and scattering method for analysis of the diffraction and scattering patterns are measured. The coloring composition of the present invention preferably has a particle size in the range of 0.1 μm to several mm, but the shape of the particles changes according to the manufacturing conditions or the method for recovering the dried powder, so it is not limited to a specific particle size. However, in order to obtain higher solubility, those with a smaller particle size are preferred, and those with a central value of particle size distribution in the range of 0.1 to 100 μm are preferred.

By performing elemental composition and structural analysis on the surface of the powder of the coloring composition of the present invention, information about the fine structure of molecular level or atomic level can be inferred. Specifically, ultraviolet light, X-rays, or electron beams can be used to obtain information about the analysis of the composition of atoms on the surface of the sample or within the particles or the bonding between atoms. In particular, X-ray powder X-ray diffraction (XRD) can be used to obtain information about the lattice constants, periodicity, etc. of the configuration (crystal structure) of atoms or molecules.

The decomposition starting temperature of the powder can be analyzed by performing thermogravimetric-differential thermal analysis (TG-DTA) of the coloring composition of the present invention. The decomposition starting temperature is preferably 250 ° C or higher, more preferably 300 ° C or higher, and particularly preferably 360 ° C or higher. When applied to a color filter, the higher the decomposition start temperature, the better.

The solubility of the powder of the coloring composition of the present invention is expressed in terms of solubility, and the solubility means the ratio of the maximum amount of coloring composition that can dissolve the powdered coloring composition in a specific solvent, for example, "% by weight ( "Solvent name, temperature)" and other units. The solubility is obtained by, for example, mixing a sample in a specific solvent, stirring the solvent at a certain temperature for a certain period of time to prepare a saturated solution, and measuring the concentration of the prepared saturated solution, or by It is obtained by concentration measurement such as liquid chromatography (LC) or absorbance measurement.

The coloring composition contained in the colorant for the color filter must be well dissolved or dispersed in an organic solvent containing a resin or the like in the manufacturing steps of the colorant for the color filter and the color filter, so it is preferable to The solubility of organic solvents is high. The organic solvent is not particularly limited, and specific examples include: esters such as ethyl acetate and n-butyl acetate; ethers such as diethyl ether and propylene glycol monomethyl ether (PGME); propylene glycol monomethyl ether acetic acid Ethers such as esters (PGMEA); ketones such as acetone and cyclohexanone; alcohols such as methanol and ethanol; diacetone alcohol (DAA); aromatic hydrocarbons such as benzene, toluene and xylene; N, N-di Acylamines such as methylformamide (DMF) and N-methylpyrrolidone (NMP); dimethylsulfoxide (DMSO) and so on. These solvents can be used alone or in combination of two or more. Among these, the coloring composition containing the dibenzopiperan dye of the present invention is preferably excellent in solubility in PGME.

Regarding the spectroscopic characteristics (transmittance and reflectance) of the powder of the coloring composition of the present invention, it is important whether the pigment is used alone as a colorant for color filters or when it is mixed with other pigments and used The color characteristics of the color filter have a direct influence. The measurement methods are as follows: a method of measuring the absorption (or transmission) spectrum of a solution or dispersion state, or the absorption (or transmission) spectrum of a film coated on a glass or transparent resin substrate. In addition, there is a method of measuring light reflected and scattered on or near the particle surface by directly irradiating the powder with light.

In the above analysis method, powder X-ray diffraction, thermal analysis or solubility analysis are suitable as the analysis method of the coloring composition containing the dibenzopiperan dye of the present invention, especially the powder X-ray diffraction system is suitable for use Judging and speculating on whether it is mixed with other materials, dissolved and uniformly dispersed, or whether a film can be obtained that can obtain heat resistance or light resistance, and whether it exhibits the color characteristics of pigments suitable for color filters. Whether the powder has a suitable crystalline structure (powder characteristics). In powder X-ray diffraction, CuKα rays (hn = 8.048 keV, wavelength λ = 0.15418 nm) or MoKα rays (hn = 17.5 keV, wavelength λ = 0.071073 nm) are generally used as X-ray sources, preferably CuKα X-ray powder X-ray diffraction.

In the present invention, the coloring composition containing at least one dibenzopiperan dye represented by the general formula (1) is used in the measurement of the powder X-ray diffraction at a diffraction angle (Bragg angle) 2θ = 2 Within the range of ° ～ 35 °, the maximum number of diffraction peaks observed for each sample is 30. In the case of powder X-ray diffraction, when a peak appears in the range of 2θ = 2 ° to 35 °, it is shown that there is a periodicity of atoms of about 0.2 nm to about 4.0 nm in the solid powder sample. For example, in a dibenzopiperan dye such as acid red 52, which is a representative dibenzopiperan dye, the shortest interatomic bonding distance is about 0.13 ± 0.02 nm, and the distance between two nitrogen atoms is About 1 nm. In addition, the maximum width of the molecule of the dibenzopiperan dye represented by the general formula (1) is 1 to 2 nm, and the crystal lattice of a general molecular crystal is the same as the maximum width of the molecule. That is, the diffraction pattern observed within the range of the above-mentioned diffraction angle shows information about the arrangement between the atoms in the dibenzopiperan molecule, or about the inter-molecule between the dibenzopiperan molecules in the powder Configuration information. For this reason, powder X-ray diffraction is excellent as a method for analyzing the internal state of powders containing dibenzopiperan dyes.

Therefore, in the present invention, the coloring composition containing at least one dibenzopiperan dye represented by the general formula (1) is preferably used in the measurement of powder X-ray diffraction of CuKα rays at a diffraction angle of 2θ A maximum of 30 diffraction peaks were observed within the range of 2 ° to 35 °. In the range of this diffraction angle, within the range of 2θ = 18 ° to 35 °, the distance between the atoms in the dibenzopiperan molecule is observed, such as carbon-carbon, carbon-nitrogen, carbon-oxygen (may It is directly bonded to each other, and may have periodic peaks such as through other atoms, specifically, it is preferable to observe more than 5 significant peaks within 2θ = 2 ° -25 ° And the maximum is 20.

In the present invention, the coloring composition containing at least one dibenzopiperan dye represented by the general formula (1) is used in the measurement of powder X-ray diffraction of CuKα rays at a diffraction angle of 2θ = 2 ° ～ Within the range of 10 °, for example, a diffraction peak with a distance of the same degree or more between the two nitrogen atoms of the dibenzopiperan molecule is observed, so it can be considered to include not only the dibenzopiperan molecule The information between the atoms in it also contains information about the periodicity between two adjacent dibenzopiperan molecules. In the present invention, the inventors found that the preparation method of the powder of dibenzopiperan dye, the powder X-ray diffraction pattern obtained as a result thereof, and the characteristics of the color filter evaluated using the dye, In particular, color rendering (contrast ratio) has a correlation. Specifically, the coloring composition containing at least one dibenzopiperan dye represented by the general formula (1) is CuKα-ray powder diffraction angle (2θ) under powder X-ray diffraction = 3 ° ～ 7 ° The peak does not seem to be significant. For example, the presence or absence of a significant peak within 2θ = 5 ° shows the presence or absence of periodicity of 1.7 to 1.8 nm in the coloring composition. The periodicity of 1.7 to 1.8 nm is estimated to be equivalent to the distance between dibenzopiperan molecules. By the preparation method of the sample, it is possible to obtain a configuration of dibenzopiperan molecules with no such regularity. , Showing that the structures of dibenzopiperan molecular crystals are different. The difference in crystal structure also affects the size or interaction of the intermolecular forces between the dibenzopiperan molecules, so as a result, it also affects the solubility, dispersibility, and other pigments or color filters used in the solvent. The interaction of resin materials etc. has a great influence, and directly affects various physical properties of the color filter. As a colorant for a color filter, it is preferable that the number of peaks with a diffraction angle (2θ) = 3 ° to 7 ° under powder X-ray diffraction of CuKα rays is 0 (no significant peaks are observed).

The colorant for a color filter of the present invention includes a coloring composition containing at least one dibenzopiperan dye represented by the general formula (1), and components generally used for manufacturing color filters. Regarding the general color filter, for example, in the case of the method using the photolithography step, a liquid can be prepared by mixing pigments such as dyes or pigments with resin components (including monomers and oligomers) or solvents The prepared liquid is coated on a substrate such as glass or resin, and photopolymerized using a photomask to produce a colored pattern of a pigment-resin composite film that is soluble / insoluble in a solvent, washed, and heated. In addition, in the electrodeposition method or the printing method, a coloring pattern is produced by mixing a pigment with a resin or other components. Therefore, as specific components in the colorant for color filters of the present invention, at least one of dibenzopiperan dyes represented by general formula (1), other dyes or pigments such as pigments, resin components, organic Other additives such as solvents and photopolymerization initiators. In addition, you can choose from these components, and you can add other components as needed.

When the coloring composition containing the dibenzopiperan dye of the present invention is used as a colorant for color filters, it can also be used for color filters for various colors, but it is preferably used as a blue or red color Colorants for optical filters.

The colorant for a color filter containing a dibenzopiperan dye of the present invention may be used alone or two or more dibenzopiperan dyes, or other dyes or pigments may be mixed in order to adjust the color tone. . When used in a colorant for a red color filter, it is not particularly limited, and examples include red pigments such as CI Pigment Red 177, CI Pigment Red 209, CI Pigment Red 242, and CI Pigment Red 254; other red-based lakes Pigments; red dyes such as CI Acid Red 88, CI Basic Violet 10, etc. When used as a coloring agent for blue color filters, it is not particularly limited, and examples include basic dyes such as CI basic blue 3, 7, 9, 54, 54, 65, 75, 77, 99, 129; CI Acid Dyes such as Acid Blue 9, 74; Disperse Dyes such as Disperse Blue 3, 7, 377; Spilon Dyes; Cyanine, Indigo, Phthalocyanine, Anthraquinone, Methylene, Triarylmethane, Indane Shilin series, 㗁 series, di 㗁 series, azo series, not belonging to the dibenzopiperan series of the present invention; other blue series lake pigments and other blue series dyes or pigments.

The mixing of the other pigments in the colorant for color filters containing dibenzopiperan dyes of the present invention is preferably relative to the dibenzopiperan dyes (in the case of two or more, it is the sum of these ) Is 5 to 2000% by weight, more preferably 10 to 1000% by weight. The mixing of pigment components such as dyes in the colorant for liquid color filters is preferably 0.5 to 70% by weight relative to the entire colorant, and more preferably 1 to 50% by weight.

As the resin component in the color filter for color filters of the present invention, as long as it has the properties required for the manufacturing method or use of the color filter resin film formed as such, known ones can be used. Examples include acrylic resins, olefin resins, styrene resins, polyimide resins, urethane resins, polyester resins, epoxy resins, vinyl ether resins, phenol (phenolic) resins, other transparent resins, Photocurable resins or thermosetting resins can be used in appropriate combination with these monomer or oligomer components. In addition, copolymers of these resins may be used in combination. Regarding the content of the resin in the colorant for color filters, in the case of a liquid coloring agent, it is preferably 5 to 95% by weight, and more preferably 10 to 50% by weight.

Examples of other additives in the colorant for color filters of the present invention include components necessary for polymerization or hardening of resins such as photopolymerization initiators and crosslinking agents, and examples of color filters for liquids Surfactants or dispersants required for the stability of the ingredients in the colorants for appliances. These are well-known ones that can be manufactured using color filters, and are not particularly limited. The mixing of the total amount of the additive in the entire solid content of the colorant for color filters is preferably 5 to 60% by weight, more preferably 10 to 40% by weight. [Example]

Hereinafter, the embodiments of the present invention will be specifically described by examples, but the present invention is not limited to the following examples. In addition, the identification of the compound obtained in the Example was performed by ¹ H-NMR analysis (Nuclear Magnetic Resonance Device manufactured by JEOL Ltd., JNM-ECA-600).

[Example 1] [Preparation of powder for coloring composition] In a 3 L reaction vessel, put acid red 52 (150 g) represented by the following formula (A-3) and 1.2 L of methanol at 50 ° C Dissolve under low temperature, add 7.5 g of activated carbon (model: Egret A-2, hereinafter referred to as "Egret"), and stir for 1 hour. The reaction solution was filtered twice using filter paper (model: GF-75 manufactured by ADVANTEC). The filtrate was concentrated and dissolved in 1.12 L of methanol at 50 ° C, then 1.12 L of ethyl acetate was added, stirred for 3 hours, and then filtered. The filtrate was dried under reduced pressure at 60 ° C for 24 hours to obtain a green crystalline coloring composition (104.4 g). NMR analysis of the coloring composition was performed, and it was confirmed that no component of an organic solvent such as methanol was observed.

[化 17]

[Powder X-ray diffraction measurement] Powder X-ray diffraction (XRD) measurement (manufactured by Rigaku Co., Ltd., sample horizontal X-ray diffraction device, RINT) was performed on the powder of the coloring composition obtained as described above -2200, Ultima type, X-ray source: CuKα rays (hn = 0.15418 nm, 30 kV, 30 mA), divergent slit: 1/2 °, scattering slit: 1/2 °, light receiving slit: 0.15 mm, Scanning step: 0.02 °, scanning speed: 2 ° / min, scanning diffraction angle range: 2θ = 2 ° ～ 35 °). The results are shown in Figure 1. In addition, Table 1 shows the number of significant diffraction peaks observed in the range of 2θ = 2 ° to 7 °, 7 ° to 15 °, 15 ° to 25 °, and 25 ° to 35 °. Among them, for peaks less than about 5% of the maximum peak intensity, and the peak shoulder is not clear, it is not counted.

[Table 1]

[Characteristics of Color Filter] Using the above-mentioned coloring composition, a color filter was produced by the following method to produce a color filter, and the contrast ratio was measured. 30 parts of the evaluation resin prepared from benzyl methacrylate and methacrylic acid, 70 parts of PGME, and 2 parts of dye were mixed to obtain a coloring composition. This coloring composition was coated on a glass substrate (50 × 50 × 0.7 mm) using a spin coater (Model: MS-B100 manufactured by Mikasa Co., Ltd.). The glass substrate was dried at 90 ° C for 10 minutes. The obtained coated substrate is sandwiched between two polarizing plates, the backlight is turned on, and the brightness of the polarizing plates when traveling straight and parallel is measured. The contrast ratio was calculated from the measured brightness ratio. The results are shown in Table 1.

[Example 2] In a 1 L reaction vessel, acid red 52 (40 g) represented by the above formula (A-3) and 0.32 L of methanol were placed, dissolved at 60 ° C, and activated carbon was added (model: egret ) 2 g, stirring for 1 hour. The reaction solution was filtered twice at 50 ° C with filter paper (model: GF-75 manufactured by ADVANTEC). Move the filtrate to a tank (30 cm × 40 cm), put it into a reduced-pressure desiccator under the conditions of temperature-heating time of 50 ℃ -2 hours, 65 ℃ -2 hours, 80 ℃ -20 hours It was dried under reduced pressure to obtain a purple crystalline coloring composition (40.3 g). NMR analysis of the coloring composition was performed, and it was confirmed that no component of an organic solvent such as methanol was observed. For this coloring composition, the results of measuring powder X-ray diffraction and contrast ratio in the same manner as in Example 1 are shown in FIG. 1 and Table 1.

[Comparative Example 1] In a 10 L reaction vessel, put acid red 52 (700 g) represented by the above formula (A-3), activated carbon (model: egret) 40 g, and methanol 6 L at 55 ° C After stirring for 1 hour, it was filtered at 50 ° C. The filtrate was concentrated to a weight of 1/3 under reduced pressure, the tank was opened, and air-dried at 25 ± 2 ° C for 4 days, and dried at 80 ° C under reduced pressure for 5 days. The time when the weight loss became 0.4% by weight per day was regarded as the end of drying, and it was obtained as a coloring composition (715 g) containing a dibenzopiperan dye (A-20) of red-purple powder. NMR analysis of the coloring composition was performed, and it was confirmed that no component of an organic solvent such as methanol was observed. The results of measuring powder X-ray diffraction and contrast ratio for this coloring composition are shown in FIG. 1 and Table 1.

[Comparative Example 2] The coloring composition obtained in Comparative Example 1 was pulverized using a mortar. The results of measuring powder X-ray diffraction and contrast ratio for this coloring composition are shown in FIG. 1 and Table 1.

As shown in FIG. 1 and Table 1, the number of diffraction peaks in the range of diffraction angle 2θ = 3 ° to 7 ° under the powder X-ray diffraction of CuKα rays of the coloring compositions of Example 1 and Example 2 The number is 0, and the contrast ratio of the color filter made by it is used as a color filter for practical use without problems.

On the other hand, in the coloring compositions of Comparative Examples 1 and 2, the number of diffraction peaks in the range of the diffraction angle 2θ = 3 ° to 7 ° under the powder X-ray diffraction of CuKα rays is 1 The ratio is lower than the examples.

As described above, the color filter produced using the coloring composition containing the dibenzopiperan dye of the present invention has a relatively high contrast ratio, so it is more useful as a colorant for color filters. [Industry availability]

The coloring composition containing the dibenzopiperan dye of the present invention is more useful as a coloring agent for color filters, and can produce color filters with excellent contrast ratios.

FIG. 1 is a diagram of powder X-ray diffraction (XRD) of coloring compositions of Examples and Comparative Examples of the present invention.

Claims (5)

A coloring composition, which contains the dibenzopiperan dye represented by the following general formula (1), and contains at least one CuKα ray powder diffraction angle (2θ) 3 ° under powder X-ray diffraction The number of diffraction peaks in the range of ～ 7 ° is 0 dibenzopiperan dyes, [Chem. 1] [In the formula, R ¹ to R ⁴ each independently represent a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, or a ring having 3 to 20 carbon atoms which may have a substituent. Alkyl groups, R ⁵ to R ⁷ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, and a carbon atom which may have a substituent Cycloalkyl having 3-20 carbon atoms, linear or branched alkoxy groups having 1-20 carbon atoms which may have substituents, cyclic alkoxy groups having 3-20 carbon atoms which may have substituents, Or it may have a linear or branched alkenyl group having 2 to 20 carbon atoms, and R ⁵ and R ⁶ may also be bonded to each other to form a ring; M represents an alkali metal atom]. The coloring composition according to claim 1, wherein in the above general formula (1), R ¹ to R ⁴ are linear or branched alkyl groups having 1 to 10 carbon atoms which may have a substituent. The coloring composition according to claim 1 or 2, which contains two or more dibenzopiperan dyes represented by the above general formula (1), and the weight concentration in the entire dibenzopiperan dyes In the ratio, the weight concentration ratio of the smallest dibenzopiperan dye is 0.1 to 50% by weight. A colorant for a color filter, which contains the coloring composition according to any one of claims 1 to 3. A color filter using the colorant for a color filter according to claim 4.