JP7801403B2 - Coloring composition for color filters, color filters and display devices - Google Patents

Description

The present invention relates to a coloring composition for color filters, and more specifically to a coloring composition for color filters that has a specified total content of specific metal elements and contains an alkali-soluble resin having a hydrocarbon ring, and a color filter obtained using the same.
In addition, when producing a coloring composition for color filters, a colorant liquid is used. In this specification, a "colorant dispersion liquid" in which a colorant such as a pigment or a dye is present in a dispersed state in a solvent, and a "colorant solution" in which a colorant such as a dye is present in a dissolved state in a solvent are collectively referred to as a "colorant liquid".

Color filters used in displays and the like generally comprise a transparent substrate, a colored layer, a light-shielding portion, etc., and methods for forming this colored layer include pigment dispersion, dyeing, electrodeposition, and printing. Of these, the pigment dispersion method is widely used due to its spectral characteristics, durability, pattern shape, precision, etc. (Patent Documents 1 and 2).

In recent years, advances in displays have led to increased demand for LCD displays, organic EL displays, and other displays. As a result, there is a strong demand for improved image quality in terms of the performance of these displays, including improvements in color rendering, contrast, brightness, and color reproducibility.

Furthermore, in recent years, as tablets, smartphones, and other devices have become increasingly high-definition, the black matrix has become thinner, and this has led to a particular problem of parallax color mixing, in which the colors of adjacent pixels appear to mix when the display is viewed from the side.
To solve this problem, it is necessary to reduce the thickness of the color filters, and specifically, it is required to achieve a thickness of about 50% to 70% of the conventional thickness.
On the other hand, there is also a demand for high color rendering in the chromaticity range defined by the "adobeRGB standard" and the "DCI standard"("DCI" stands for Digital Cinema Initiatives) for the reproduced colors of pixels.

Therefore, in order to reduce the film thickness of color filters and improve the color rendering of pixels, it is necessary to increase the concentration of color materials in coloring compositions for color filters.

However, when an attempt is made to increase the colorant concentration of a coloring composition for color filters or a colorant liquid used therein, it becomes difficult to disperse and dissolve the colorant well in the first place, and there are cases where stability over time cannot be obtained.
Furthermore, as the coloring material concentration increases, the components required for patterning to form pixels relatively decrease, resulting in problems such as poor developability (low development speed; large amount of development residue; etc.).

In other words, even if a coloring composition for color filters that can be dispersed and dissolved at high concentrations and has excellent color performance was created, there was also the problem that it was difficult to achieve compatibility with developability during color filter production.

On the other hand, Patent Documents 3 to 6 are known to specify the content of metal elements in color filters or coloring compositions for producing color filters.

Patent document 3 discloses a technology for preventing contamination of liquid crystal elements and semiconductor elements adjacent to color filters by specifying the total amount of sodium ions (Na ⁺ ) and potassium ions (K ⁺ ) contained in R (red), G (green), B (blue), and BK (black) pixels.
Patent Document 4 discloses a technology for achieving a high light-shielding rate and a low surface reflectance by specifying the total amount of sodium (Na) and potassium (K) in the resin that coats the carbon black for the black matrix.

Patent Document 5 describes a pigment dispersion liquid in which the electrical conductivity and the contents of sodium (Na), potassium (K), and magnesium (Mg) are specified, and it is said that a color filter obtained using this pigment dispersion liquid has an excellent voltage holding ratio and therefore good display stability.
Patent Document 6 describes an organic pigment composition for color filters in which the contents of sodium ions (Na ⁺ ), potassium ions (K ⁺ ), and magnesium ions (Mg ⁺ ) contained in C.I. Pigment Green 58 are specified, and a color filter obtained using the composition is said to have excellent display response.

However, since colorant liquids for color filters used in displays require extremely high levels of dispersion and dissolution, the above-mentioned techniques are still insufficient, and further improvements are desired to solve the above-mentioned problems.
In particular, in recent years, as parallax color mixing has become a problem due to the trend toward higher definition, and high color rendering of pixels has been required, resulting in a demand for thinner color filters. In this situation, there has been a demand for a coloring composition for color filters that has excellent performance in terms of the dispersion stability and solubility of color materials, various image characteristics, developability during color filter production, and the like.

Japanese Patent Application Laid-Open No. 2007-133131 Japanese Patent Application Laid-Open No. 2009-244617 Japanese Unexamined Patent Publication No. 7-198928 Japanese Patent Application Publication No. 9-071733 JP 2009-007432 A JP 2014-119487 A

The present invention has been made in view of the above-mentioned background art, and an object of the present invention is to provide a coloring composition for color filters that has excellent properties such as achieving a thin film thickness for a color filter, reducing parallax color mixing when a display is viewed from the side, and achieving high color rendering in a certain chromaticity range with respect to the reproduced colors of pixels.
Another object of the present invention is to provide a coloring composition for color filters that can satisfactorily disperse and dissolve coloring materials therein, has excellent viscosity stability, and is excellent in developability (high development speed and small amount of development residue).

As a result of extensive research to achieve the above-mentioned objective, the present inventors have unexpectedly discovered that a color filter coloring composition and color filter that solve the above-mentioned problems can be obtained by reducing the content of "calcium (Ca) and iron (Fe)" (hereinafter, the number in parentheses may be referred to as the "first specified metal element") and "magnesium (Mg), aluminum (Al), and chromium (Cr)" (hereinafter, the number in parentheses may be referred to as the "second specified metal element." Furthermore, the "first specified metal element" and the "second specified metal element" may be collectively referred to as the "specified metal element.") which are metal elements other than extremely common metal elements such as sodium (Na) and potassium (K) contained in a colorant liquid for color filters or a coloring composition for color filters.

Furthermore, the present inventors have found that when "specific metal elements"("first specific metal element" and "second specific metal element") are present that are mixed in from the solvents, process water, equipment components, etc. used in the process of producing the colorant (particularly when the "first specific metal element" is present), the initial viscosity of the colorant liquid during production increases, the stability over time deteriorates, the development time becomes longer, and appropriate patterns and good pixels cannot be obtained.
The inventors have also found that by reducing the amount of "specific metal elements" in the coloring materials, solvents, etc. that are the raw materials for colorant solutions for color filters (particularly by reducing the amount of "specific metal elements" in the coloring materials), it is possible to obtain a coloring composition for color filters and a color filter that solve the above-mentioned problems.

Furthermore, if the coloring composition contains a large amount of the specific metal element, not only will the development time be longer, but the amount of development residue will also increase, making water stains more likely to occur. This tendency becomes stronger particularly when the concentration of the coloring material is high.
The present inventors have found that by reducing the contamination of the specific metal elements and further using an alkali-soluble resin having a hydrocarbon ring as the alkali-soluble resin, it is possible to reduce development residues and suppress the occurrence of water stains, and have thus completed the present invention.

That is, the present invention provides a coloring composition for color filters containing a colorant, a solvent, a polymerization initiator, and an alkali-soluble resin, wherein the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is 120 ppm by mass or less relative to the total mass of the coloring composition, and the alkali-soluble resin has a hydrocarbon ring.

The present invention also provides a color filter having a colored layer that is a cured product of the above-mentioned coloring composition for color filters.

The present invention also provides a display device characterized by having the above-mentioned color filter.

As described above, there are known techniques for preventing contamination of liquid crystal elements or semiconductor elements adjacent to color filters by avoiding the inclusion of extremely common metal elements such as sodium (Na) or potassium (K), for achieving a high light-shielding rate and low surface reflectance by specifying the content of the metal in the pigment-coated resin, and for improving display stability and display responsiveness by increasing the voltage holding ratio by specifying the content of the metal in the color filter.
That is, techniques are known for reducing common metallic elements to improve specific optical and electrical properties that are directly attributable to the inclusion of those metals.

However, there is no known technology that specifies the content of a specific metal element (especially a first specific metal element) and improves its appearance (higher concentration, etc.) or physical properties (lower viscosity, dispersion stability, etc.) at the colorant liquid stage, ultimately resulting in an excellent color filter.

In other words, it was not previously known that by specifying the content of "calcium (Ca) and iron (Fe)" (first specified metal elements) and further specifying the content of "magnesium (Mg), aluminum (Al), and chromium (Cr)" (second specified metal elements), a colorant liquid with low viscosity (appropriate viscosity) and excellent dispersion stability and solubility can be obtained even at high colorant concentrations, and as a result, a color filter with excellent image characteristics and development characteristics can be obtained.

In recent years, there has been a demand for thinner color filters to solve the problems mentioned above, while at the same time, high color rendering within a certain chromaticity range is also required for the reproduced colors of pixels. By using the coloring composition for color filters of the present invention, it is possible to achieve thinner color filters, reduce parallax mixing, achieve high color rendering, and provide color filter coloring compositions and color filters that have excellent developability during patterning, etc.

The present invention is described below, but is not limited to the specific embodiments below and can be modified as desired within the scope of the technical concept.

The "coloring composition for color filter" of the present invention is a coloring composition containing a colorant, a solvent, a polymerization initiator, and an alkali-soluble resin, and is characterized in that the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is 120 ppm by mass or less with respect to the entire coloring composition.
For example, by using a colorant liquid for color filters that contains a colorant and a solvent and in which the total mass of calcium (Ca) and iron (Fe) is 180 mass ppm or less with respect to the entire colorant liquid for color filters, it is easy to prepare a color composition for color filters in which the total mass of calcium (Ca) and iron (Fe) is within this range.
In the present invention, the "color material liquid for color filters" may be abbreviated simply as the "color material liquid", and the "coloring composition for color filters" may be abbreviated simply as the "coloring composition".

<Colorant>
In the present invention, the color material is not particularly limited as long as it can produce a desired color when a colored layer of a color filter is formed, and examples thereof include various inorganic pigments, organic pigments, dyes, etc., which may be used alone or in combination of two or more.
Among these, organic pigments are preferably used because they have high color development and heat resistance.

<<Inorganic pigments>>
Specific examples of inorganic pigments that can be used in the present invention include titanium oxide, barium sulfate, calcium carbonate, zinc white, lead sulfate, yellow lead, zinc yellow, red iron oxide (red iron (III) oxide), cadmium red, ultramarine, iron blue, chromium oxide green, cobalt green, umber, titanium black, synthetic iron black, and carbon black.

<<Organic pigments>>
The organic pigment used in the present invention is a colored pigment (including achromatic pigments such as black), and is not particularly limited as long as it can produce the desired color as an organic pigment for a color filter. Here, "for color filters" includes all pigments for coloring color filters, such as those for pixel portions and black matrix portions.

The organic pigments used in the present invention also include lake pigments that have been made dispersible by bonding various substituents to dyes or by making them insoluble in solvents using known laking (chlorination) techniques.

Here, the organic pigment also includes achromatic pigments such as white, black, and gray, and specifically, pigments of various colors such as blue pigments, green pigments, red pigments, yellow pigments, purple pigments, orange pigments, brown pigments, and black pigments can be used.
The pigment dispersion in the present invention is used as a color filter material, and therefore mainly contains blue pigments, green pigments, red pigments, and black pigments. However, pigments of the above-mentioned color tones are also used in order to adjust the transmission and absorption wavelengths of these pigments.
Among the above, blue pigments, green pigments, red pigments, yellow pigments, purple pigments, etc. are preferred in terms of achieving the effects of the present invention.

Specific examples of organic pigments are listed below by pigment number. Note that "C.I." below stands for Color Index.

Red pigments include C.I. Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 14, 15, 16, 17, 21, 22, 23, 31, 32, 37, 38, 41, 47, 48, 48:1, 48:2, 48:3, 48:4, 49, 49:1, 49:2, 50:1, 52:1, 52:2, 53, 53:1, 53:2, 53:3, 57, 57:1 , 57:2, 58:4, 60, 63, 63:1, 63:2, 64, 64:1, 68, 69, 81, 81:1, 81:2, 81:3, 81:4, 83, 88, 90:1, 101, 101:1, 104, 108, 108:1, 109, 112, 113, 114, 122, 123, 144, 146, 147, 149, 151, 16 6, 168, 169, 170, 172, 173, 174, 175, 176, 177, 178, 179, 181, 184, 185, 187, 188, 190, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 216, 220, 221, 224, 230, 231, 232, 233, 234 5, 236, 237, 238, 239, 242, 243, 245, 247, 249, 250, 251, 253, 254, 255, 256, 257, 258, 259, 260, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, etc.
Among these, C.I. Pigment Red 48:1, 122, 168, 177, 202, 206, 207, 209, 224, 242, 254, etc. are preferable, and C.I. Pigment Red 177, 209, 224, 254, etc. are particularly preferable.

Examples of blue pigments include C.I. Pigment Blue 1, 1:2, 9, 14, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17, 19, 25, 27, 28, 29, 33, 35, 36, 56, 56:1, 60, 61, 61:1, 62, 63, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78, and 79.
Among these, C.I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, etc. are preferable, and C.I. Pigment Blue 15:6, etc. are particularly preferable.

Examples of green pigments include C.I. Pigment Green 1, 2, 4, 7, 8, 10, 13, 14, 15, 17, 18, 19, 26, 36, 45, 48, 50, 51, 54, 55, 58, and 59.
Among these, C.I. Pigment Green 7, 36, 58, 59, etc. are preferable.

Yellow pigments include C.I. Pigment Yellow 1, 1:1, 2, 3, 4, 5, 6, 9, 10, 12, 13, 14, 16, 17, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 41, 42, 43, 48, 53, 55, 61, 62, 62:1, 63, 65, 73, 74, 75, 81, 83, 87, 93, 94, 95, 97, 100, 101, 104, 105, 108, 109, 110, 111, 116, 117, 119, 120, 126, 127, 127:1, 128, 129, 133, 134, 136, 138 , 139, 142, 147, 148, 150, 151, 153, 154, 155, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 172, 173, 174, 175, 176, 180, 181, 182, 183, 184, 185, 188, 189, 190, 191, 191:1, 192, 193, 194, 195, 196, 197, 198, 199, 200, 202, 203, 204, 205, 206, 207, 208, 213, etc.
Among these, C.I. Pigment Yellow 83, 117, 129, 138, 139, 150, 154, 155, 180, 185, 213, etc. are preferable, and C.I. Pigment Yellow 83, 138, 139, 150, 180, 185, etc. are particularly preferable.

Examples of orange pigments include C.I. Pigment Orange 1, 2, 5, 13, 16, 17, 19, 20, 21, 22, 23, 24, 34, 36, 38, 39, 43, 46, 48, 49, 61, 62, 64, 65, 67, 68, 69, 70, 71, 72, 73, 74, 75, 77, 78, and 79.
Among these, C.I. Pigment Orange 38, 71, etc. are preferable.

Examples of purple pigments include C.I. Pigment Violet 1, 1:1, 2, 2:2, 3, 3:1, 3:3, 5, 5:1, 14, 15, 16, 19, 23, 25, 27, 29, 31, 32, 37, 39, 42, 44, 47, 49, and 50.
Among these, C.I. Pigment Violet 19, 23, etc. are preferable, and C.I. Pigment Violet 23, etc. are particularly preferable.

In the present invention, one type of the above pigment may be used, or two or more types may be used.
Furthermore, when the colorant liquid in the present invention is a colorant liquid for a black matrix of a color filter, a black pigment can be used as the colorant.
An example of the black pigment is carbon black.
The organic pigment of an achromatic color such as black may be the achromatic pigment alone or may be a mixture with a colored pigment such as red, green, or blue.

Preferred organic pigments for use in the present invention, from the standpoint of chemical structure and light transmission spectrum, include anthraquinone pigments such as Pigment Red 177; diketopyrrolopyrrole pigments such as Pigment Red 254; azo pigments such as azomethine pigments such as Pigment Yellow 150; quinophthalone pigments such as Pigment Yellow 138; dioxazine pigments such as Pigment Violet 23; phthalocyanine pigments such as Pigment Blue 15:6; benzimidazolone pigments such as Pigment Yellow 180; quinoxaline pigments such as Pigment Yellow 213; quinacridone pigments; isoindoline pigments; isoindolinone pigments; indanthrene pigments; perylene pigments; and the like.

In particular, in terms of achieving the effects of the present invention, it is particularly preferable that the organic pigment (colorant) is one or more organic pigments selected from the group consisting of anthraquinone pigments, diketopyrrolopyrrole pigments, azo pigments, quinophthalone pigments, dioxazine pigments, and phthalocyanine pigments.

In the present invention, organic pigments (colorants) having the same chemical structural skeleton, i.e., the same system, may be used in one type within that system, or in two or more types. Also, two or more types may be used across systems. They may also be mixed crystals.

Organic pigments having the above-described chemical structure are often used as organic pigments (colorants) for color filters, and therefore often require a colorant dispersion at a high concentration. In this case, the specific metal element has a large effect on dispersibility and developability, and further, the specific metal element is likely to be mixed in during the production process. Therefore, the above-described effects of the present invention are particularly likely to be achieved.
Specifically, for example, Pigment Red 254, Pigment Red 177, Pigment Yellow 150, Pigment Yellow 185, Pigment Yellow 138, Pigment Yellow 139, Pigment Blue 15:6, Pigment Violet 23, Pigment Green 58, or Pigment Green 59 is particularly preferred for the above reasons.

As the organic pigment in the present invention, lake pigments in which dyes are insolubilized using a known laking (chlorination) method can also be used.
The dye used as the raw material for the lake pigment can be appropriately selected from conventionally known dyes, such as azo dyes, metal complex azo dyes, anthraquinone dyes, triphenylmethane dyes, xanthene dyes, cyanine dyes, naphthoquinone dyes, quinoneimine dyes, methine dyes, phthalocyanine dyes, perinone dyes, and dipyrromethene dyes.

Among these, xanthene dyes (xanthene acid dyes) are preferred as raw materials for lake pigments because of their high heat resistance. Among the xanthene acid dyes, compounds represented by the following general formula (II), i.e., rhodamine acid dyes, are particularly preferred.

[In general formula (II), R ^I to R ^IV each independently represent a hydrogen atom, an alkyl group, an aryl group, or a heteroaryl group, and R ^I and R ^III , and R ^II and R ^IV may be bonded to form a ring structure. R ^V represents an acidic group, and X represents a halogen atom. m represents an integer of 0 to 5. General formula (II) has one or more acidic groups, and n is an integer of 0 or more.]

The alkyl group in R ^I to R ^IV is not particularly limited. Examples include linear or branched alkyl groups having 1 to 20 carbon atoms which may have a substituent, and among these, linear or branched alkyl groups having 1 to 8 carbon atoms are preferred, and linear or branched alkyl groups having 1 to 5 carbon atoms are more preferred. The substituent that the alkyl group may have is not particularly limited, and examples thereof include an aryl group, a halogen atom, a hydroxyl group, and the like. Examples of substituted alkyl groups include a benzyl group, and the group may further have a halogen atom or an acidic group as a substituent.
The aryl group in R ^I to R ^IV is not particularly limited. Examples include aryl groups having 6 to 20 carbon atoms which may have a substituent, and among these, a phenyl group, a naphthyl group, etc. which may have a substituent are preferred. The heteroaryl group in ^{R I} to R ^IV includes heteroaryl groups having 5 to 20 carbon atoms which may have a substituent, and the heteroatom is preferably a nitrogen atom, an oxygen atom, a sulfur atom, etc.
Examples of the substituent that the aryl group or heteroaryl group may have include an alkyl group having 1 to 5 carbon atoms, a halogen atom, an acidic group, a hydroxyl group, an alkoxy group, a carbamoyl group, and a carboxylic acid ester group.
R ^I to R ^IV may be the same or different.

Specific examples of the acidic group or a salt thereof include a carboxyl group (-COOH), a carboxylato group (-COO ^- ), a carboxylate group (-COOM, where M represents a metal atom), a sulfonate group (-SO ₃ ^- ), a sulfo group (-SO ₃ H), and a sulfonate group (-SO ₃ M, where M represents a metal atom), and among these, it is preferable to have at least one of a sulfonate group (-SO ₃ ^- ), a sulfo group (-SO ₃ H), and a sulfonate group (-SO ₃ M). Examples of the metal atom M include a sodium atom and a potassium atom.

Of the compounds represented by formula (II), Acid Red 50, Acid Red 52, Acid Red 289, Acid Violet 9, Acid Violet 30, Acid Blue 19, and the like are preferred in terms of increasing brightness.
From the viewpoint of heat resistance, a compound having a betaine structure in which m=1 and n=0 in general formula (II) is preferred.
Among these, it is preferable that m = 1 and n = 0, R ^I and R ^II are each independently an alkyl group or an aryl group, and R ^III and R ^IV are each independently an aryl group or a heteroaryl group, since this makes it possible to form a colored layer having excellent brightness and light resistance.
The method for producing the compound represented by the general formula (II) is not particularly limited, but it can be obtained by referring to, for example, JP-A-2010-211198.

The metal lake colorants for the above xanthene acid dyes use a lake agent containing a metal atom. The use of a lake agent containing a metal atom increases the heat resistance of the colorant. Such lake agents are preferably those containing metal atoms that form divalent or higher metal cations.

As a guideline, if the amount of lake pigment dissolved in 10 g of solvent (or mixed solvent) is 10 mg or less, it can be determined that the lake pigment (dye) is dispersible in that solvent (or mixed solvent).

<<Acidic dye derivatives>>
The organic pigment in the present invention preferably contains an acidic dye derivative, since the above-described effects of the present invention can be easily achieved. The use of an acidic dye derivative is particularly preferred because it enables fine dispersion, and when used for a color filter, it is possible to obtain a colorant dispersion liquid that has high dispersion stability, high contrast, high light transmittance, and high brightness.
Furthermore, when an acidic dye derivative is used, the effect of reducing the specific metal element in the present invention is more pronounced, and the above effects can be exerted synergistically.

Here, the term "acidic dye derivative" refers to a dye derivative having an acidic group in its chemical structure, and is particularly preferably a dye derivative having one or more pigment skeletons selected from the group consisting of anthraquinone pigments, diketopyrrolopyrrole pigments, azo pigments, quinophthalone pigments, dioxazine pigments, and phthalocyanine pigments, and having an acidic group.
Among the acidic dye derivatives, quinophthalone dye derivatives, which are dye derivatives having the pigment skeleton of a quinophthalone pigment and an acidic group, are more preferred in terms of improving dispersibility.

The acidic group of the acidic dye derivative is preferably at least one selected from the group consisting of a sulfo group, a sulfonamide group, a carboxy group, and metal salts or ammonium salts of these functional groups.
The average number of acidic groups introduced per pigment molecule is not particularly limited, but is preferably 0.5 to 5, more preferably 0.6 to 4, and particularly preferably 0.7 to 3.5.
The introduction of an acidic group makes it possible to finely disperse the colorant, and is therefore preferable because, when used for a color filter, a colorant dispersion liquid having advantages such as high dispersion stability, high contrast, high light transmittance, and high brightness can be obtained. Furthermore, by reducing the content of the specific metal element, a synergistic effect can be achieved, and the above-mentioned effects can be further obtained.

The organic pigment of the present invention preferably contains a pigment and an acidic dye derivative. The acidic dye derivative interacts with the pigment and is adsorbed to or incorporated into the pigment surface during the preparation of pigment particles.
Furthermore, by adsorbing to the surface of the pigment, it makes the surface of the pigment acidic, increasing its affinity with the pigment dispersant more than the organic pigment itself, and also acting as an intermediary between the pigment dispersant and the pigment.
Furthermore, the acidic dye derivative, which interacts with the basic dispersant, is adsorbed onto the pigment surface, allowing the basic dispersant to be efficiently positioned on the pigment surface, which enables fine dispersion and dispersion stabilization, making it excellent for use in color filters.

The content of the acidic dye derivative in the entire organic pigment in the present invention is not particularly limited, but is preferably 0.5 to 30 parts by mass, more preferably 1 to 15 parts by mass, and particularly preferably 2 to 10 parts by mass, relative to 100 parts by mass of the pigment.
By setting the content to be equal to or greater than the above lower limit, stable dispersion or fine dispersion becomes possible, and a synergistic effect with the reduction of the specific metal element described above is achieved, and by setting the content to be equal to or less than the above upper limit, changes in chromaticity due to an excess of the acidic dye derivative can be suppressed.

In the present invention, one or more of the above-mentioned acidic dye derivatives may be used as the organic pigment, and one or more of the above-mentioned acidic dye derivatives may be used for one type of pigment.

The acidic dye derivative may be added to the pigment particle dispersion at any stage. However, in consideration of the fact that the acidic dye derivative is adsorbed to or incorporated into the pigment surface, the acidic dye derivative can also be added to the pigment during the process of producing the pigment. For example, the acidic dye derivative can be added during the process of synthesizing the pigment, during the process of solvent salt milling the pigment using a kneader or the like, during the treatment process after the process, during the process of dry-pulverizing the pigment using an attritor or the like, during the dispersing process, during the treatment process after the dispersion, or the like.
The solvent may be added to the good solvent or poor solvent in the reprecipitation method, or may be added after the precipitation of pigment particles or when the pigment particles are subsequently concentrated or redispersed.

Furthermore, according to the present invention, by using a (salt-type) basic block dispersant or a (salt-type) basic graft dispersant as described below, the salt-forming moiety has strong adsorption to the pigment, and in particular to the acidic dye derivative adsorbed to the pigment surface. Meanwhile, the main chain and side chain of the polymer dispersant, which have affinity for the solvent, improve the dispersibility of the pigment dispersion for color filters, increase the organic pigment concentration, achieve low viscosity, and suppress changes over time in the pigment dispersion. As a result, the developability is improved in the evaluation of the coloring composition for color filters.

＜＜Dye＞＞
In the present invention, dyes can also be used as coloring materials. Specific examples of dyes that can be used include the same dyes as those described above as "dyes that are raw materials for lake pigments."

As a guideline, if the amount of dye dissolved in 10 g of a solvent (or mixed solvent) is 10 mg or less, the dye can be dispersed in the solvent (or mixed solvent) and can be used as a colorant dispersion liquid.
A dye that dissolves in an amount of more than 10 mg in 10 g of a solvent (or mixed solvent) can be dissolved in the solvent to form a colorant solution, which can be used as a coloring composition for color filters.

<<Particle size of colorant>>
The particle size of the coloring material is not particularly limited, but is preferably 30 nm to 500 nm, more preferably 40 nm to 300 nm, and particularly preferably 50 nm to 200 nm.
If the particle size is too small, dispersibility and resolubility may decrease, and workability may decrease due to contamination caused by fine powder.
On the other hand, if the particle size is too large, dispersibility, dispersion stability, light resistance, etc. will be deteriorated, and the effect of reducing the content of specific metal elements such as calcium (Ca) and iron (Fe) will be less likely to be achieved, and the effects of the present invention described above will not be achieved, and in particular, good contrast may not be obtained.

Here, "resolubility" refers to the property of the solid content of a color filter coloring composition that has been dried once to dissolve again in a solvent. For example, if the color filter coloring composition adheres to the tip of the die lip during application with a die coater and the drying rate is fast, a solid will form as it dries. However, if the solid does not easily dissolve in the color filter coloring composition when application is resumed, some of the solid on the die lip will peel off and easily adhere to the color filter color layer, causing foreign matter defects.

<Dispersant>
The coloring composition for color filters of the present invention may contain a dispersant, if necessary.
The dispersant used in the present invention can be appropriately selected from known dispersants, and examples thereof include cationic, anionic, nonionic, amphoteric, silicone, and fluorine-based surfactants; polymer dispersants; and low-molecular-weight dispersants. Among these, polymer dispersants (including polymer surfactants) are preferred because they can disperse particles uniformly and finely.

Examples of polymer dispersants include modified polyurethane, modified polyacrylate, modified polyester, and modified polyamide.
Specific examples include (co)polymers of "unsaturated carboxylic acid esters such as (meth)acrylic acid esters"; (partial) amine salts, (partial) ammonium salts, or (partial) alkylamine salts of "(co)polymers of unsaturated carboxylic acids such as (meth)acrylic acid"; (co)polymers of "unsaturated carboxylic acid esters such as (meth)acrylic acid esters having a primary, secondary, or tertiary amino group", (partial) salts of the amino group of the (co)polymers, and (partial) acid-modified products of the amino group of the (co)polymers; (co)polymers of "hydroxyl group-containing unsaturated carboxylic acid esters such as hydroxyl group-containing (meth)acrylic acid esters" and modified products thereof; polyurethanes; unsaturated polyamides; polysiloxanes; long-chain polyaminoamidophosphates; amides obtained by reacting poly(lower alkyleneimines) with free carboxyl group-containing polyesters and salts thereof; and the like.

<<Polymer dispersants and low molecular weight dispersants>>
The "dispersant" in the present invention is not particularly limited, and known polymer dispersants or low molecular weight dispersants can be used to disperse colorants.

Examples of polymer dispersants include random dispersants made of random (co)polymers; block dispersants made of block copolymers; and graft dispersants made of graft (co)polymers in which repeating units are attached as pendant (branch-like) side chains at various points to the main chain.
Also preferred are salt-type dispersants in which at least a portion of the structural units of the (co)polymer have a salt structure. Such salt-type dispersants apply to all of the random-type dispersants, block-type dispersants, and graft-type dispersants, and they are preferably used.

Examples of polymeric dispersants include (co)polymers of unsaturated carboxylic acid esters such as poly(meth)acrylic acid esters; (partial) amine salts, (partial) ammonium salts, and (partial) alkylamine salts of (co)polymers of unsaturated carboxylic acids such as poly(meth)acrylic acid; (co)polymers of hydroxyl group-containing unsaturated carboxylic acid esters such as hydroxyl group-containing poly(meth)acrylic acid esters and modified products thereof; polyurethanes; unsaturated polyamides; polysiloxanes; long-chain polyaminoamidophosphates; amides obtained by reacting poly(lower alkyleneimine) with polyesters containing free carboxy groups and salts thereof; and (meth)acrylate copolymers having polyester groups in the side chains.

Among these, preferred are poly(meth)acrylates, sodium maleate-olefin copolymers, polyesters containing terminal carboxy groups (e.g., JP 54-34009 B); polyesters containing acidic and/or basic groups that use tetrakis(2-hydroxyalkyl)ethylenediamine as a starting material (e.g., JP 2-245231 A); copolymers obtained by copolymerizing macromonomers (oligomers having a polymerizable unsaturated group at one end), monomers having a hydroxyl group, and monomers containing a carboxy group (e.g., JP 8-259876 A); and copolymers obtained by copolymerizing macromonomers (oligomers having a polymerizable unsaturated group at one end), and monomers having nitrogen atoms (e.g., JP 10-339949 A).

Examples of low molecular weight dispersants include anionic compounds having a sulfonic acid group, a carboxylic acid group, or the like; cationic compounds having a salt of an aliphatic amine, a quaternary ammonium salt, or the like; nonionic compounds having a hydroxyl group, an oxyethylene chain, or the like; and polymer compounds.
Specific examples include sorbitan fatty acid esters, polyoxyethylene alkylamines, alkyldiamines, alkanolamine derivatives (US Pat. No. 3,536,510), and the like.

Among dispersants, polymeric dispersants are preferred, and among polymeric dispersants, basic block dispersants and/or basic graft dispersants are preferred because they have functionally separate colorant adsorption sites and solvent affinity sites, and because by keeping the "total content of calcium (Ca) and iron (Fe)" and the "total content of calcium (Ca) and iron (Fe) plus the total content of magnesium (Mg), aluminum (Al) and chromium (Cr)" described below below below to a certain value or less, they have a synergistic effect with the effects of the present invention, such as dispersion stability, colored image properties, and developability, and they have a synergistic effect when used in combination with the acidic dye derivatives described above.

Here, "the dispersant is a basic block type dispersant and/or a basic graft type dispersant" means that the dispersant is a basic block type dispersant, a basic graft type dispersant, a combination of a basic block type dispersant and a basic graft type dispersant, or a dispersant that is both a basic block type dispersant and a basic graft type dispersant. Furthermore, the combined use of dispersants that are neither basic block type dispersants nor basic graft type dispersants is not excluded.

<<Basic Block Type Dispersant>>
The term "basic block dispersant" refers to a dispersant composed of a block copolymer of a monomer having a basic group such as an amino group, a monoalkylamino group, a dialkylamino group, an amide group, a salt thereof, or a trialkylammonium group (hereinafter abbreviated as "monomer a") with another monomer different from the aforementioned monomer (hereinafter abbreviated as "monomer b"), and may be a binary copolymer or a copolymer of ternary or higher components. Note that "monomer a" also includes those in which the above-mentioned "alkyl" is replaced with "aryl,""aralkyl,""alkenyl," etc.

The above-mentioned monomer a is preferably a (meth)acrylate compound containing a quaternary ammonium base and/or a secondary or tertiary amino group or a salt thereof in which the hydrogen bonded to the nitrogen atom may be substituted with a substituent, and particularly preferably a tertiary amino group and/or a quaternary ammonium base.

The monomer a is preferably one that provides a structural unit represented by the following general formula (1) or a salt form (described later) of the structural unit represented by the following general formula (1). That is, in the present invention, the color material liquid for color filter is preferably one in which the dispersant is a basic block copolymer containing a structural unit represented by the following general formula (1) or a salt form thereof.
[In general formula (1), ^R1 represents a hydrogen atom or a methyl group, A represents a divalent linking group, ^R2 and ^R3 each independently represent a hydrogen atom or a hydrocarbon group which may contain a heteroatom, and ^R2 and ^R3 may be bonded to each other to form a ring structure.]

Specific examples of salts include those formed by salting a tertiary amino group, which is a unit forming a basic block copolymer, with an acid such as a sulfonic acid compound or a phosphoric acid compound.
Further, examples include those in which a tertiary amino group of dimethylaminoethyl (meth)acrylate or the like, which is a unit forming a basic block copolymer, is converted into a quaternary ammonium salt by an aryl halide, an aralkyl halide, or the like.

When the above-mentioned monomer a provides the repeating unit represented by the above general formula (1), it may be copolymerized with other polymerizable monomers as appropriate, and then reacted with a compound that reacts with an amino group, for example, an acid compound such as a sulfonic acid compound, a phosphoric acid compound, or a carboxylic acid compound; or a halogen compound such as an aryl halide, an alkyl halide, or an aralkyl halide; to convert part or all of the resultant into a quaternary ammonium salt.

The sulfonic acid compound can be a compound represented by the following general formula (2). In other words, the salt-formed product is preferably a salt-type block copolymer in which at least some of the nitrogen atoms in the structural units represented by the above general formula (1) become cations and one or more compounds selected from the group consisting of compounds represented by the following general formula (2) become anions, forming a salt.

[In general formula (2), R ^a represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, phenyl group, or benzyl group which may have a substituent; or —O—R ^e , where R ^e represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, phenyl group, or benzyl group which may have a substituent; or a (meth)acryloyl group connected via an alkylene group having 1 to 4 carbon atoms.]

The above-mentioned "halogen compounds such as aryl halides, alkyl halides, and aralkyl halides" include compounds represented by the following general formula (3). In other words, the salt-formed product is preferably a color filter colorant liquid in which the block copolymer is a salt-type block copolymer in which at least some of the nitrogen atoms in the structural units represented by the above general formula (1) become cations and one or more compounds selected from the group consisting of compounds represented by the following general formula (3) become anions, forming a salt.

[In general formula (3), R ^b , R ^b′ and R ^b″ each independently represent a hydrogen atom; an acidic group or an ester group thereof; a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may have a substituent; a vinyl group, a phenyl group or a benzyl group which may have a substituent; or —O—R ^f , where R ^f represents a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may have a substituent; a vinyl group, a phenyl group or a benzyl group which may have a substituent; or a (meth)acryloyl group connected via an alkylene group having 1 to 4 carbon atoms; and X represents a chlorine atom, a bromine atom or an iodine atom.]
X in the general formula (3) becomes a counter anion (X ⁻ ) to form a salt.

The above-mentioned phosphoric acid compound includes a compound represented by the following general formula (4). In other words, the salt-formed product is preferably a color filter colorant liquid in which the block copolymer is a salt-type block copolymer in which at least some of the nitrogen atoms in the structural units represented by the above general formula (1) become cations and one or more compounds selected from the group consisting of compounds represented by the following general formula (4) become anions, forming a salt.

[In general formula (4), R ^c and R ^d each independently represent a hydrogen atom; a hydroxyl group; a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, a phenyl group, or a benzyl group which may have a substituent; or -O-R ^g , where R ^g represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, a phenyl group, or a benzyl group which may have a substituent; or a (meth)acryloyl group connected via an alkylene group having 1 to 4 carbon atoms, with the proviso that at least one of R ^c and R ^d contains a carbon atom.]

Specific examples of the above-mentioned "a" monomer include dialkylaminoalkyl esters of (meth)acrylic acid, diarylaminoalkyl esters of (meth)acrylic acid, diaralkylaminoalkyl esters of (meth)acrylic acid, dialkenylaminoalkyl esters of (meth)acrylic acid, and salts thereof. Compounds used to form "salts thereof" include compounds represented by the above-mentioned general formulas (2) to (4).

More specifically, examples include tertiary amino group-containing compounds such as dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, diethylaminoethyl (meth)acrylate, and diethylaminopropyl (meth)acrylate; salts of these tertiary amino group-containing compounds; amides such as N-methylol (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylamide, and N,N-dimethylaminopropyl (meth)acrylamide; salts of quaternary ammonium group-containing compounds such as (meth)acryloylaminopropyl trimethylammonium chloride, (meth)acryloyloxyethyl trimethylammonium chloride, (meth)acryloyloxyethyl triethylammonium chloride, and (meth)acryloyloxyethyl benzyldimethylammonium chloride; and the like.

Particularly preferred examples include dimethylaminoethyl (meth)acrylate, sulfonate of dimethylaminoethyl (meth)acrylate, phenylphosphonate of dimethylaminoethyl (meth)acrylate, and (meth)acryloyloxyethyl benzyl dimethyl ammonium chloride.

When used in color filters, the basic block copolymer in which the above-mentioned monomer a is (co)polymerized or its salt-type dispersant enables fine dispersion and dispersion stabilization, and maintains good dispersion stability even when the colorant concentration is increased. In other words, it enables the colorant dispersion liquid or coloring composition to be highly concentrated, and the color filters obtained using them can have high color rendering, thin films, high contrast, good developability, good resolubility, etc., and the synergistic effect of limiting the content of the specific metal element makes it easier to achieve the effects of the present invention described above.

The colorant is firmly adsorbed to the nitrogen moiety contained in the a monomer (preferably the structural unit represented by general formula (1)), resulting in excellent colorant dispersibility, and the colorant that is firmly adsorbed to the nitrogen moiety and surrounded by the dispersant is easily washed away while remaining adsorbed to the dispersant during development, so that the colorant is not left behind on the substrate and the generation of residues is easily suppressed.
Similarly, the colorant that is firmly adsorbed to the nitrogen site and surrounded by the dispersant is likely to be washed away in a resolubilizable solvent while still adsorbed to the dispersant.

Examples of the b monomer include aromatic group-containing monomers such as acrylates, such as benzyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, and phenoxyethyl (meth)acrylate; styrenes, such as styrene; and vinyl ethers, such as phenyl vinyl ether.
Further examples include (meth)acrylic acid ester monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, glycidyl (meth)acrylate, and hydroxyethyl (meth)acrylate; vinyl acetate; acrylonitrile; and allyl group-containing compounds such as allyl alkyl ethers.

The monomer b is also preferably a carboxyl group-containing monomer, which refers to a monomer containing a copolymerizable unsaturated double bond and a carboxyl group.
Examples of the carboxy group-containing monomer include (meth)acrylic acid, vinylbenzoic acid, maleic acid, maleic acid monoalkyl ester, fumaric acid, itaconic acid, crotonic acid, cinnamic acid, and (meth)acrylic acid dimer.
Further examples include addition reaction products of a monomer having a hydroxyl group, such as 2-hydroxyethyl(meth)acrylate, with a cyclic anhydride, such as maleic anhydride, phthalic anhydride, or cyclohexanedicarboxylic anhydride; and ω-carboxy-polycaprolactone mono(meth)acrylate.
Further, as the precursor of the carboxy group, there may be mentioned a carboxy group-containing monomer using an acid anhydride such as maleic anhydride, itaconic anhydride, or citraconic anhydride.
Among these, (meth)acrylic acid is particularly preferred from the viewpoints of copolymerizability, cost, solubility, etc.

The overall reason for selecting the above b monomer is that it has affinity for solvents, making it possible to finely disperse and stabilize the dispersion, especially when used for color filters.

If the polymer block containing the a monomer or its salt is designated "A" and the polymer block containing the b monomer is designated "B," the basic block dispersant of the present invention may be an A-B block copolymer, an A-B-A block copolymer, a B-A-B block copolymer, an A-B-A-B block copolymer, or a block copolymer with a higher order, but is preferably an A-B block copolymer.

Block copolymers containing the a monomer or its salt can improve the dispersibility of colorants because the block portions containing the a monomer or its salt adsorb to the colorant, while the block portions not containing the a monomer or its salt have affinity for the solvent.

The weight average molecular weight (Mw) of the basic block copolymer in the present invention is not particularly limited, but is preferably in the range of 500 to 100,000, more preferably in the range of 1,000 to 30,000, particularly preferably in the range of 3,000 to 20,000, and most preferably in the range of 4,000 to 15,000.
When the content is within the above range, it is possible to achieve both "wettability for uniformly dispersing the colorant" and dispersion stability. Furthermore, when the colorant dispersant of the present application is used as a component of a coloring composition, if the upper limit is not more than the above value, the viscosity of the dispersion does not become too high, and developability and resolution do not decrease, while if the lower limit is not less than the above value, sufficient dispersibility is obtained.

Here, the weight average molecular weight (Mw) is determined by gel permeation chromatography (GPC) as a value converted into standard polystyrene.
Measurement of the weight average molecular weight (Mw) of the basic block copolymer was carried out using an HLC-8120GPC manufactured by Tosoh Corporation, with the elution solvent being N-methylpyrrolidone to which 0.01 mol/L of lithium bromide had been added, and the polystyrene standards for the calibration curve were Mw 377,400, 210,500, 96,000, 50,400, 20,650, 10,850, 5,460, 2,930, 1,300, and 580 (all manufactured by Polymer Laboratories, Inc., Easi PS-2 series) and Mw 1,090,000 (manufactured by Tosoh Corporation), and the measurement column was TSK-GEL ALPHA-M × 2 (manufactured by Tosoh Corporation).

The amine value is not particularly limited, but is preferably 15 to 200 mgKOH/g, more preferably 30 to 150 mgKOH/g, and particularly preferably 40 to 130 mgKOH/g.
If the amine value is too small, sufficient dispersion stability cannot be obtained, whereas if it is too large, the solubility in the solvent decreases.
The amine value can be determined in accordance with JIS-K7237.

The acid value is preferably 0 to 50 mgKOH/g, more preferably 1 to 30 mgKOH/g, and particularly preferably 2 to 18 mgKOH/g. Within this range, developability is excellent. Furthermore, if the acid value is below the upper limit, "resist pattern peeling" is less likely to occur.

When the molecular weight, amine value, or acid value is within the above range, the toner is easily dispersed, good dispersion stability can be maintained even when the colorant concentration is increased, the developability is good, and the effects of the present invention described above are easily exhibited due to the synergistic effect with the limited content of the specific metal element.
As a result, a color display obtained using the colorant dispersion liquid has high contrast, high light transmittance, and high brightness.

<<Basic Graft-Type Dispersant>>
The term "basic graft-type dispersant" refers to a basic dispersant made of a (co)polymer in which repeating units are bonded as side chains to the main chain.
Specifically, examples of such dispersants include those obtained by synthesizing side chains first and then (co)polymerizing the synthesized side chains, i.e., dispersants made of (co)polymers containing as a polymerization component a macromonomer having a polymerizable unsaturated group at one end (an oligomer having a polymerizable unsaturated group at one end and a repeating unit).
Further, there may be mentioned dispersants made of (co)polymers in which a main chain is synthesized first and then repeating units are attached here and there to the main chain as pendant side chains (like branches).

The basicity of the "basic graft-type dispersant" may be imparted in any manner, but it is preferable that the basicity is imparted by copolymerizing a nitrogen atom-containing monomer having basicity.
The basic monomer to be copolymerized is not particularly limited, but specific examples include the "monomer a" described in the section "basic block type dispersant" above.

The "macromonomer having a polymerizable unsaturated group at one end" is not particularly limited, and known macromonomers can be used.
The polymerization components constituting the repeating units in such macromonomers are not particularly limited, but specific examples include styrene-based monomers such as styrene and α-methylstyrene; (meth)acrylic acid ester-based monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, glycidyl (meth)acrylate, benzyl (meth)acrylate, and hydroxyethyl (meth)acrylate; (meth)acrylamide-based monomers such as (meth)acrylamide, N-methylolacrylamide, N,N-dimethylacrylamide, and N,N-dimethylaminoethylacrylamide; vinyl acetate; acrylonitrile; and allyl group-containing compounds such as allyl alkyl ethers. The macromonomer in the present invention is preferably one having units formed by polymerizing the above polymerization components.

In the "basic graft-type dispersant", other polymerizable monomers may be copolymerized in addition to the "macromonomer having a polymerizable unsaturated group at one end" and the "basic monomer to be copolymerized".
Such "other polymerizable monomers" are not particularly limited, but specific examples include the "monomer b" described above in the section "basic block type dispersant".

There are no particular limitations on the rate at which macromonomers are introduced, but it is preferable to introduce an average of 0.1 to 20 macromonomers per 100 repeating units of the main chain, and it is particularly preferable to introduce an average of 0.3 to 10 macromonomers per 100 repeating units of the main chain.

The molecular weight of the basic graft-type dispersant in the present invention is not particularly limited, but is usually 1,000 to 100,000, preferably 2,000 to 40,000, more preferably 3,000 to 30,000, particularly preferably 4,000 to 25,000, and even more preferably 5,000 to 20,000, in terms of polystyrene equivalent weight average molecular weight (Mw).
When the content is within the above range, the colorant is easily dispersed, making it possible to finely disperse the colorant in the "final dispersion step in preparing the colorant dispersion," and shortening the dispersion time. As a result, a color display obtained using the colorant dispersion has high contrast, high light transmittance, and high brightness.

<<Commercially available products>>
In the present invention, commercially available products used as dispersants are not limited, but specific examples include EFKA-4046, EFKA-4047, EFKA Polymer 10, EFKA Polymer 400, EFKA Polymer 401, EFKA Polymer 4300, EFKA Polymer 4310, EFKA Polymer 4320, and EFKA Polymer 4330 (all manufactured by BASF Japan Ltd.), Disperbyk 111, Disperbyk 161, and Disperbyk 162. 65, Disperbyk167, Disperbyk182, Disperbyk2000, Disperbyk2001, BYK-LPN6919, BYK-LPN21116 (all manufactured by BYK Japan K.K.), SOLSPERSE24000, SOLSPERSE27000, SOLSPERSE28000 (all manufactured by Lubrizol Corporation), AJISPER (registered trademark) PB821, PB822 (manufactured by Ajinomoto Fine-Techno Co., Ltd.), and the like.

<Solvent>
The solvent for the colorant liquid in the present invention is not particularly limited, and any known solvent may be used.

Specific examples of the solvent include alcohols such as methanol, ethanol, and propanol; ethers such as tetrahydrofuran; alkylene glycol ethers such as propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol methyl ethyl ether, propylene glycol monoethyl ether, and propylene glycol diethyl ether; dialkylene glycol ethers such as diethylene glycol monomethyl ether, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol methyl ethyl ether, dipropylene glycol monoethyl ether, and dipropylene glycol diethyl ether; trialkylene glycol ethers such as tripropylene glycol monomethyl ether, tripropylene glycol dimethyl ether, tripropylene glycol methyl ethyl ether, tripropylene glycol monoethyl ether, and tripropylene glycol diethyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ... alkylene glycol monoalkyl ether acetates such as dipropylene glycol monomethyl ether acetate and dipropylene glycol monoethyl ether acetate; dialkylene glycol monoalkyl ether acetates such as dipropylene glycol monomethyl ether acetate and dipropylene glycol monoethyl ether acetate; trialkylene glycol monoalkyl ether acetates such as tripropylene glycol monomethyl ether acetate and tripropylene glycol monoethyl ether acetate; aromatic hydrocarbons such as toluene and xylene; methyl ethyl ketone, methyl propyl ketone, methyl amyl ketone, cyclopentanone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, methyl Ketones such as isobutyl ketone; and esters such as ethyl 2-hydroxypropionate, methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate, butyl 3-methoxyacetate, butyl 3-methyl-3-methoxyacetate (3-methoxy-3-methyl-1-butyl acetate), ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-2-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 2-hydroxypropanoate, ethyl acetate, butyl acetate, methyl lactate, ethyl lactate, and isoamyl acetate.
These solvents may be used alone or in combination of two or more.

Of these, propylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, ethyl 3-ethoxypropionate, butyl 3-methoxyacetate, butyl 3-methyl-3-methoxyacetate (3-methoxy-3-methyl-1-butyl acetate), diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, and methyl 2-hydroxypropanoate are particularly preferred.

In addition, from the standpoint of developability and resolubility, it is also preferable to use a mixed solvent containing two or more solvents.

When using a mixed solvent, it is preferable to use a glycol ether acetate solvent (such as the alkylene glycol monoalkyl ether acetates, dialkylene glycol monoalkyl ether acetates, and trialkylene glycol monoalkyl ether acetates mentioned above) as the first solvent because of its high safety, moderate volatility, and good dispersibility due to its moderate solubility. Among these, ethylene glycol monomethyl ether acetate or propylene glycol monomethyl ether acetate, which have a boiling point (referring to the boiling point at atmospheric pressure; the same applies hereinafter) of less than 150°C, are more preferred, with propylene glycol monomethyl ether acetate (PGMEA) being particularly preferred.

As the second solvent (a solvent other than the first solvent), a solvent having an alcoholic hydroxyl group (hereinafter sometimes referred to as an "alcohol-based solvent") or a solvent having a boiling point of 150°C or higher is preferred.
The second solvent may be used alone or in combination of two or more.

When an alcohol-based solvent is used as the second solvent, the dispersibility and resolubility are improved, and the alcohol-based solvent has high polarity and is excellent in dissolving the dye.
Examples of alcohol-based solvents include propylene glycol monomethyl ether (boiling point 121°C), 3-methoxy-3-methyl-1-butanol (boiling point 174°C), diacetone alcohol (boiling point 166°C), and ethyl lactate (boiling point 151°C).

When a mixed solvent is used, the content of the alcohol-based solvent is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 2% by mass or less, based on the total solvent content, and is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 1% by mass or more.
Within the above range, the solubility of the dispersant is improved, and the dissolution of the dispersant in the first solvent is not hindered, resulting in good dispersion stability.

When the first solvent has a boiling point of less than 150°C, using a solvent having a boiling point of 150°C or higher as the second solvent reduces the occurrence of uneven drying and improves resolubility.
Examples of solvents having a boiling point of 150°C or higher include diethylene glycol ethyl methyl ether (boiling point 179°C), 3-methoxy-3-methyl-1-butyl acetate (boiling point 188°C), ethyl 3-ethoxypropionate (boiling point 170°C), and 3-methoxybutyl acetate (3-methoxybutyl acetate) (boiling point 172°C).

When a mixed solvent is used, the content of the solvent having a boiling point of 150°C or higher is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on the total solvent content, and is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more.
Within the above range, uneven drying is unlikely to occur, and the drying time does not become too long, resulting in good productivity.

Furthermore, by using an alcohol-based solvent in combination with a solvent having a boiling point of 150° C. or higher as the second solvent, resolubility becomes extremely good and uneven drying is less likely to occur.
In this case, the content ratio (by mass) of the solvent having a boiling point of 150° C. or higher to the alcohol-based solvent is preferably 0.1 to 25, more preferably 0.3 to 20, and particularly preferably 0.5 to 10.

The boiling point of the above-mentioned "solvent with a boiling point of 150°C or higher" is preferably 240°C or lower, and particularly preferably 200°C or lower, in order to prevent drying times from becoming too long.

<Other ingredients>
The coloring material liquid may contain other components such as an alkali-soluble resin, which will be described later, within the range that does not impair the effects of the present invention.

<Content ratio>
In the color material liquid for color filters of the present invention, the content ratio of the color material, dispersant, and solvent is not particularly limited, but the following is preferred.
The amount of the dispersant is preferably 5 to 200 parts by mass, more preferably 10 to 150 parts by mass, particularly preferably 15 to 100 parts by mass, and most preferably 20 to 60 parts by mass, per 100 parts by mass of the colorant.
The colorant content is preferably 3 to 40 parts by mass, more preferably 5 to 35 parts by mass, and particularly preferably 7 to 30 parts by mass, per 100 parts by mass of the colorant liquid.

When the "content ratio of colorant to dispersant" is as described above, the colorant is easily dispersed, excellent dispersion stability is obtained, a colorant dispersion liquid with a high colorant concentration is obtained, and the dispersion time can be shortened.
As a result, a color filter obtained using the colorant dispersion liquid exhibits the above-mentioned effects, and serves as a display with high color rendering, high contrast, thin filmability, high light transmittance, and high brightness.

Furthermore, the above-mentioned "colorant to solvent content ratio" is preferable because it provides excellent dispersibility, dispersion stability, solubility, etc., and can be adjusted to a suitable viscosity. Therefore, when the colorant liquid of the present invention contains at least a polymerization initiator and an alkali-soluble resin (and preferably a polymerizable polyfunctional compound) to obtain a colored composition, it is easy to adjust the content ratio of these to an optimal value.

<Dispersion method>
The coloring material is dispersed in a solvent in the presence of a dispersant and incorporated therein. When the coloring material is incorporated as a wet dispersion, the effects of the present invention are particularly exhibited.

In the present invention, the dispersion time is not particularly limited, but in order to obtain an appropriate dispersed particle size of the colorant, a time of 0.01 to 50 hours is preferred, 0.02 to 30 hours is more preferred, and 0.05 to 10 hours is particularly preferred.

<Content of specific metal elements in colorant liquid>
The color material liquid for color filter in the present invention is characterized in that the total mass of calcium (Ca) and iron (Fe) contained in the color material liquid is 180 mass ppm or less with respect to the entire color material liquid.
The total mass of calcium (Ca) and iron (Fe) is preferably as small as possible, regardless of cost and the like. Specifically, the total mass of calcium (Ca) and iron (Fe) is preferably 140 mass ppm or less, more preferably 70 mass ppm or less, particularly preferably 30 mass ppm or less, even more preferably 15 mass ppm or less, and most preferably 5 mass ppm or less, relative to the entire colorant liquid.

When the "total mass of calcium (Ca) and iron (Fe) contained in the colorant liquid" is below the above upper limit, the colorant can be dispersed well even when the concentration of the colorant contained in the colorant liquid is increased, dispersion stability is well maintained over time, and a colorant liquid for color filters that is resistant to deterioration over time despite its high colorant concentration can be obtained.

Furthermore, when a coloring composition for a color filter is produced using a coloring material liquid in which the "total mass of calcium (Ca) and iron (Fe) contained in the coloring material liquid" is equal to or less than the above upper limit, the coloring material concentration in the coloring composition can be increased, and as a result, a color filter that achieves high color density even with a low film thickness can be obtained.
By using such a color material liquid, it is possible to obtain a color filter having a thin film thickness, with little parallax color mixing, high color rendering, and a colored composition and color filter having excellent developability in patterning.

The coloring composition of the present invention, obtained using a coloring material solution with a limited amount of metal, allows for an increased coloring material concentration, resulting in good dispersion performance, dispersion stability, and solubility, while also achieving good developability during color filter production. In other words, for example, in an alkaline developer, the unexposed areas are more likely to dissolve together with the coloring material in the coloring composition.

There is no particular lower limit for the "total mass of calcium (Ca) and iron (Fe) contained in the colorant liquid," but it is preferably 1 ppm by mass or more, and particularly preferably 3 ppm by mass or more. At or above the above lower limit, improvements in dispersibility, solubility, and developability are sufficient, eliminating the costs required for removing excess metal elements.

In the color material liquid for color filter of the present invention, it is further preferable that the total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the color material liquid is 200 mass ppm or less with respect to the entire color material liquid.
The total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the colorant liquid is more preferably 140 mass ppm or less, particularly preferably 60 mass ppm or less, and even more preferably 20 mass ppm or less, based on the total mass of the colorant liquid.

Furthermore, the total mass of magnesium (Mg) and chromium (Cr) contained in the colorant liquid is preferably 200 mass ppm or less, more preferably 140 mass ppm or less, particularly preferably 60 mass ppm or less, and even more preferably 20 mass ppm or less.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

When the "total mass of calcium (Ca) and iron (Fe) contained in the colorant liquid" is below the aforementioned upper limit, and the "total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the colorant liquid" is below the aforementioned upper limit, the colorant concentration in the colorant liquid can be increased and still be dispersed better, the dispersion stability is maintained even better over time, and a colorant liquid for color filters that is even less susceptible to deterioration over time despite its high colorant concentration can be obtained.

The "total mass of calcium (Ca) and iron (Fe) contained in the colorant liquid" is equal to or less than the upper limit, and the calcium (Ca) content is preferably 160 ppm by mass or less, more preferably 100 ppm by mass or less, particularly preferably 60 ppm by mass or less, and even more preferably 30 ppm by mass or less, relative to the entire colorant liquid.
Furthermore, the "total mass of calcium (Ca) and iron (Fe) contained in the colorant liquid" is equal to or less than the upper limit, and the content of iron (Fe) is preferably 30 ppm by mass or less, more preferably 20 ppm by mass or less, particularly preferably 10 ppm by mass or less, and even more preferably 5 ppm by mass or less, relative to the total amount of the colorant liquid.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

The "total mass of calcium (Ca) and iron (Fe) contained in the colorant liquid" is equal to or less than the upper limit, and the "total mass of calcium (Ca), iron (Fe), magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the colorant liquid" is preferably 290 mass ppm or less, more preferably 260 mass ppm or less, particularly preferably 190 mass ppm or less, even more preferably 100 mass ppm or less, and most preferably 50 mass ppm or less, relative to the entire colorant liquid.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

Furthermore, the "total mass of calcium (Ca), iron (Fe), magnesium (Mg), and chromium (Cr) contained in the colorant liquid" is preferably 290 mass ppm or less, more preferably 260 mass ppm or less, particularly preferably 190 mass ppm or less, even more preferably 100 mass ppm or less, and most preferably 50 mass ppm or less, relative to the entire colorant liquid.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

<Principle of action>
The principle of action of the present invention to exhibit the effects described above, such as improvement in dispersion stability, is believed to be as follows, although this does not limit the scope of the invention.
That is, when calcium (Ca), iron (Fe), or the specific metal elements are present in large amounts near the colorant, it is presumed that the adsorption of the dispersant to the colorant is inhibited.Furthermore, it is presumed that the salt-type dispersant or acidic dye derivative that contributes to improving dispersibility forms a salt with the specific metal element, and therefore the dispersant or acidic dye derivative cannot contribute to improving dispersibility.

It is also possible that divalent or higher cations, such as cations of specific metal elements, have a greater effect on the reduction in dispersibility than monovalent cations such as sodium ions (Na ⁺ ) and potassium ions (K ⁺ ). Metal cations with a higher valence have a greater effect on aggregation, so it is thought that the "upper limit of the total mass of Ca and Fe, which are metal elements all having a valence of divalent or higher, and further the upper limit of the total mass of Mg, Al, and Cr, which are similarly metal elements all having a valence of divalent or higher," have been reduced, resulting in improved "dispersion stability."
It is also believed that reducing the content of Fe, which is a metal element that provides trivalent cations, and more preferably reducing the content of Al and Cr, which are metal elements that also provide trivalent cations, in addition to reducing the content of Fe, greatly influenced the improvement in dispersion stability.

Therefore, when the content of the specific metal element is low as specified in the present invention, the above-mentioned problems are less likely to occur, and it is presumed that this improves dispersibility and the developability described below.

<Method for reducing the content of specific metal elements in colorant liquid>
The colorant liquid of the present invention contains at least a colorant and a solvent, and the specific metal element is introduced from the colorant, solvent, etc., which are raw materials for the colorant liquid. It may also be mixed in from equipment used for stirring, mixing, dispersion, etc. Therefore, it is preferable to prevent the metal from being mixed in from the raw materials and equipment.
In particular, since the amount of the specific metal element carried over from the coloring material is large, it is more preferable to remove the specific metal element from the coloring material.
Furthermore, it is particularly preferable to reduce the amount of the specific metal element from the coloring material to be blended, including the acid dye derivative when used.

The method for removing the specific metal elements from the colorant is not particularly limited; they may be removed during the colorant manufacturing process, or they may be removed from the manufactured colorant using a specific removal method.

Among coloring materials, methods for removing the specific metal element from a dye production process and a produced coloring material include recrystallization, dialysis, salting out, ion exchange resin method, column chromatography, and paper chromatography, etc. From the viewpoint of cost, recrystallization is preferred.
Furthermore, the method for removing the specific metal element from the pigment among the produced color materials is preferably washing with a liquid such as alcohol or water, but from the viewpoint of cost, a washing method with water (hereinafter sometimes simply abbreviated as "water washing") is particularly preferred.

In addition to the above-mentioned "washing with liquid" such as "rinsing with water," it is also preferable not to use metals such as iron, iron-containing metals such as stainless steel, or chrome-plated parts as components of the manufacturing equipment in the colorant manufacturing process.
Examples of "manufacturing equipment components" include media such as balls in a ball mill and beads in a bead mill; inner walls of colorant manufacturing containers, dispersion containers, surface treatment containers, drying containers, filtering containers, etc.; grinder components; and agitator components.

The most preferred removal method is water washing. The water washing may be performed by suspending the colorant in water and then suspending it in water, using a batch method, or by continuous processing using running water.

The amount of the specific metal element contained in the colorant used in the colorant liquid of the present invention can be achieved by adjusting or optimizing the following.
That is, means for reducing the amount of the specific metal element contained in the colorant include reducing the content of the specific metal element contained in the washing water used (using demineralized water in which the amount of the metal has been sufficiently reduced), performing the washing by a continuous method using running water, increasing the number of washings if washing is a batch method, increasing the amount of washing water relative to the amount of colorant whether using a continuous method or a batch method, increasing the temperature of the washing water, adjusting the pH of the washing water, optimizing the stirring equipment used during washing, and lengthening the washing time.

Among these, a batch method in which the number of washings is increased, a continuous method using running water, or a method in which the temperature of the washing water is increased are particularly preferred.
The temperature of the washing water is preferably in the range of 20°C to 80°C, particularly preferably in the range of 30°C to 70°C, and further preferably in the range of 40°C to 60°C, in order to efficiently remove predetermined metals.
Among these, a continuous method using running water is preferred, and in this case, the amount of running water used is preferably 30 parts by mass to 40,000 parts by mass, more preferably 40 parts by mass to 20,000 parts by mass, particularly preferably 50 parts by mass to 10,000 parts by mass, and even more preferably 60 parts by mass to 5,000 parts by mass, per part by mass of the colorant.

The deionized water used for washing is preferably obtained by treating raw water with at least one agent selected from the group consisting of strongly acidic or weakly acidic cation exchange resins, strongly basic or weakly basic anion exchange resins, ion exchange membranes, chelating resins, activated carbon, and antibacterial activated carbon, or by treating the raw water with a combination of two or more of the above agents, or by distillation (under reduced pressure).

The method of washing with water is not particularly limited, but preferred are continuous methods in which the colorant produced by a known method is suspended in the deionized water and washed continuously by continuously supplying deionized water using a vacuum filter, belt press, centrifuge, Nutsche funnel, etc., or batch methods in which the colorant is washed while being dispersed using a filter press, homogenizer (high-pressure or low-pressure homogenizer, ultrasonic homogenizer, etc.), sand mill, ball mill, roll mill, magnetic stirrer, or other agitator.

Of these, homogenizers such as high-pressure or low-pressure homogenizers and ultrasonic homogenizers are more preferred in order to reduce the inclusion of metals such as calcium (Ca), iron (Fe), magnesium (Mg), aluminum (Al), and chromium (Cr) from the materials and media used, with ultrasonic homogenizers being particularly preferred in terms of reducing the amount of the above-mentioned specific metal elements inclusion and reducing costs.

When using the above-mentioned agitator to wash while dispersing the colorant, it is also preferable to continuously supply water and perform processing using running water in a continuous manner. In other words, using the above-mentioned agitator in combination with a continuous method is also preferable for reducing specific metal elements.

During the washing step, impurities such as metal salts, free metals, and other inorganic salts in the colorant are extracted into the deionized water. After washing, the suspension is filtered to remove the impurities extracted into the deionized water as a filtrate.
Next, the colorant wet cake obtained above is suspended again in deionized water, and if necessary, washing treatment is carried out several times in the same manner as above, with impurities removed as filtrate each time, and the finally obtained colorant wet cake is preferably dried to obtain a colorant for blending into a colorant liquid. In terms of the balance between washing effect and cost, the above-mentioned "several times" is preferably 2 to 50 times, more preferably 3 to 40 times, particularly preferably 4 to 30 times, and even more preferably 5 to 20 times. The (particularly) preferred mass of total deionized water used per part by mass of colorant is the same as in the "continuous method using running water" described above.

That is, a preferred embodiment of water washing is to wash the colorant batchwise or continuously while dispersing it in water using a stirrer such as a "high- or low-pressure homogenizer, sand mill, ball mill, roll mill, magnetic stirrer, etc." After filtering, the colorant is suspended in fresh water and washed with water. In the case of a batch method, the above process is repeated multiple times, followed by filtration and drying.

The electrical conductivity of the final filtrate from the washing step is preferably 20 μS/cm or less (particularly preferably 0.05 μS/cm to 5 μS/cm). If the washing method results in an electrical conductivity exceeding the above range, the colorant may not be sufficiently washed away, and it may not be possible to obtain a colorant solution in which the amount of the specific metal element is reduced to the range of the present invention.
That is, by repeatedly carrying out the washing treatment until the electrical conductivity reaches a level comparable to that of the deionized water used for washing the colorant, and by reducing the impurities in the colorant to almost zero, the colorant solution obtained using the colorant exhibits the effects of the present invention described above.

The completion of the washing process for the colorant used in preparing the colorant solution of the present invention can also be confirmed by ICP (Inductively Coupled Plasma) emission spectroscopy of the filtrate. ICP measurement of the filtrate is performed in the same manner as in the measurement example in the Examples, "Quantification of Metals in Colorant Solution," except that "colorant solution" in the measurement example is replaced with "filtrate."

With regard to the contents in the final filtrate of the washing step, it is preferable that both calcium (Ca) and iron (Fe) are below the detection limit, more preferably that all of calcium (Ca), iron (Fe), magnesium (Mg), aluminum (Al), and chromium (Cr) are below the detection limit, and particularly preferably that all of calcium (Ca), iron (Fe), magnesium (Mg), aluminum (Al), chromium (Cr), sodium (Na), and potassium (K) are below the detection limit.
Here, the detection limit in the measurement method of the present invention (ICP (Inductively Coupled Plasma) emission spectroscopy) is less than 0.01 ppm.

When the "content by ICP measurement" of each metal atom that is an impurity in the filtrate or the "electrical conductivity of the filtrate" exceeds the upper limit value, the content of the specified metal in the colorant liquid may not fall within the range of the present invention. As a result, it may not be possible to prepare a colorant liquid with a high colorant concentration at a low viscosity (optimum viscosity) or dispersion stability may not be achieved.
Therefore, when preparing the coloring material, it is preferable to repeat the washing process until the content of the specific metal element in the filtrate and the electrical conductivity of the filtrate fall within the above-mentioned ranges.

<Aspects of Colorant Dispersion Liquid>
The average dispersed particle size of the colorant in the colorant dispersion liquid in the present invention is not particularly limited, but is preferably 8 nm to 150 nm, more preferably 10 nm to 100 nm, and particularly preferably 12 nm to 70 nm.
Here, the average dispersed particle size of the colorant in the colorant dispersion (hereinafter sometimes simply referred to as "average dispersed particle size") is the dispersed particle size of colorant particles dispersed in a dispersion medium containing at least a solvent, and is measured using a laser light scattering particle size distribution meter. To measure the particle size using a laser light scattering particle size distribution meter, the colorant dispersion is appropriately diluted with the solvent used in the colorant dispersion to a concentration measurable with the laser light scattering particle size distribution meter (for example, 1000 times), and the particle size is measured at 23°C by dynamic light scattering using a laser light scattering particle size distribution meter (for example, a Nanotrac particle size distribution measuring device UPA-EX150 manufactured by Nikkiso Co., Ltd.). The average dispersed particle size here is the volume-average particle size.

If the average dispersed particle size is too small, light resistance may decrease. On the other hand, if the average dispersed particle size is too large, a display using a color filter obtained with the colorant dispersion may have low contrast, low light transmittance, or may not be a high-brightness display.

After dispersion, it is preferable to filter the mixture through a filter, typically 0.05 μm to 10 μm, and preferably 0.1 μm to 5 μm, to obtain the colorant dispersion liquid of the present invention.

<Coloring composition for color filters>
The colorant liquid of the present invention can be suitably used for color filter materials, colored compositions for color filters, colored compositions for color filters, liquid crystal display materials, organic EL display materials, etc. It is particularly useful as a colored composition for color filters.
The present invention is a coloring composition for color filters, comprising the color material liquid for color filters of the present invention, a polymerization initiator, and an alkali-soluble resin, wherein the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is 120 ppm by mass or less with respect to the entire coloring composition.
The alkali-soluble resin may have a polymerizable functional group, and only the polymerizable functional group of the alkali-soluble resin may be polymerized. However, it is also preferable that the coloring composition for color filters further contains a polymerizable polyfunctional compound.

The coloring composition for color filters of the present invention achieves the effects of the present invention described above.

<<Alkali-soluble resin>>
The alkali-soluble resin of the present invention is not particularly limited as long as it has a hydrocarbon ring, and any resin that can be suitably developed with an alkaline developer can be used.
The alkali-soluble resin is preferably a copolymer containing a monomer having an acid group as a copolymerization component, or may be a polymer into which an acid group has been subsequently introduced.

Here, examples of monomers having an acid group include monomers having a carboxy group such as (meth)acrylic acid and itaconic acid (methylene succinic acid); monomers having a phenolic hydroxyl group such as 4-hydroxyphenylmaleimide; and monomers having a carboxylic acid anhydride group such as maleic anhydride and itaconic anhydride.

In addition, the alkali-soluble resin in the present invention is preferably one into which a radically polymerizable double bond is introduced, in terms of improving sensitivity, and in terms of forming a strong coating film as a result of the coloring composition being imagewise exposed to light and photocured, and the unexposed area being developed.
To introduce a radically polymerizable double bond, for example, a monomer capable of introducing a radically polymerizable double bond after polymerization is (co)polymerized, and then a radically polymerizable double bond as described below is introduced into a side chain.
Examples of such "monomers capable of introducing a radically polymerizable double bond after polymerization" include monomers having a carboxy group such as (meth)acrylic acid and itaconic acid; monomers having a carboxylic acid anhydride group such as maleic anhydride and itaconic anhydride; and the like.

Examples of compounds used for introducing a radically polymerizable double bond include compounds having an "epoxy group and a radically polymerizable double bond", such as glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, and o-, m-, or p-vinylbenzyl glycidyl ether.
The acid group of the "monomer capable of introducing a radically polymerizable double bond after polymerization" reacts with the epoxy group of a compound having "an epoxy group and a radically polymerizable double bond," thereby obtaining an alkali-soluble resin into which a radically polymerizable double bond has been introduced.

In addition to the above, the alkali-soluble resin can also contain monomers copolymerizable therewith. Examples of such monomers (hereinafter referred to as "other monomers") include monomers having an ethylenically unsaturated double bond. Specific examples include styrene-based monomers such as styrene and α-methylstyrene; (meth)acrylic acid ester-based monomers such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, glycidyl (meth)acrylate, benzyl (meth)acrylate, and hydroxyethyl (meth)acrylate; (meth)acrylamide-based monomers such as (meth)acrylamide, N-methylolacrylamide, N,N-dimethylacrylamide, and N,N-dimethylaminoethylacrylamide; vinyl acetate; acrylonitrile; allyl group-containing compounds such as allyl alkyl ethers; and maleimide-based monomers such as benzylmaleimide and N-phenylmaleimide.

When the above-mentioned "monomers having an acid group," "monomers capable of introducing a radically polymerizable double bond after polymerization," "compounds used to introduce a radically polymerizable double bond," and "other monomers" are used, one or more of each may be used and subjected to (co)polymerization or reaction.

The acid value of the alkali-soluble resin in the present invention is not particularly limited, but is preferably from 30 to 200 mgKOH/g, more preferably from 40 to 150 mgKOH/g, and particularly preferably from 50 to 120 mgKOH/g.
When the upper limit of the acid value is equal to or less than the above-mentioned value, sufficient adhesion to the substrate can be obtained, and when the lower limit is equal to or greater than the above-mentioned value, sufficient alkaline developability can be obtained.

The molecular weight of the alkali-soluble resin in the present invention is not particularly limited, but is usually 3,000 to 25,000, preferably 4,000 to 20,000, and particularly preferably 5,000 to 15,000, in terms of polystyrene equivalent weight average molecular weight (Mw).
When the weight-average molecular weight (Mw) is equal to or lower than the above-mentioned upper limit, the compatibility with other constituent components is improved, the developability is improved, and the viscosity is not too high. On the other hand, when the lower limit is equal to or higher than the above-mentioned value, the adhesion to the substrate is improved.

In the present invention, it is essential that the alkali-soluble resin contain a hydrocarbon ring, as this will ensure excellent adhesion of the colored layer. The inclusion of a hydrocarbon ring, which is a bulky group, in the alkali-soluble resin suppresses shrinkage during curing, mitigating peeling from the substrate and improving adhesion to the substrate. The inventors have also discovered that using an alkali-soluble resin with a hydrocarbon ring improves the solvent resistance of the resulting colored layer, particularly suppressing swelling of the colored layer. While the exact mechanism is unclear, it is believed that the inclusion of a bulky hydrocarbon ring in the colored layer suppresses molecular movement within the colored layer, resulting in increased coating strength and suppressed swelling due to solvents.

Furthermore, if the alkali-soluble resin has a hydrocarbon ring, development residue can be suppressed, and the occurrence of water stains can be reduced.

Such hydrocarbon rings include cyclic aliphatic hydrocarbon rings which may have substituents, aromatic rings which may have substituents, and combinations thereof, and the hydrocarbon rings may have substituents such as carbonyl groups, carboxyl groups, oxycarbonyl groups, and amide groups.

Specific examples of hydrocarbon rings include aliphatic hydrocarbon rings such as cyclopropane, cyclobutane, cyclopentane, cyclohexane, norbornane, tricyclo[5.2.1.0(2,6)]decane (dicyclopentane), and adamantane; aromatic rings such as benzene, naphthalene, anthracene, phenanthrene, and fluorene; open-chain polycyclic rings such as biphenyl, terphenyl, diphenylmethane, triphenylmethane, and stilbene; and cardo structures represented by the following general formula (5).

When the hydrocarbon ring contains an aliphatic ring, the heat resistance and adhesiveness of the colored layer are improved, and the brightness of the obtained colored layer is also improved, which is preferable.
Furthermore, when the colored layer contains the cardo structure represented by the general formula (5), the curability of the colored layer is improved, and the solvent resistance (suppression of NMP swelling) is particularly preferable.

The alkali-soluble resin also preferably has a crosslinked cyclic aliphatic group, which is an aliphatic group having a structure in which two or more rings share two or more atoms.
Specific examples of the bridged cyclic aliphatic group include a norbornyl group, an isobornyl group, an adamantyl group, a tricyclodecyl group, a dicyclopentenyl group, a dicyclopentanyl group, a tricyclopentenyl group, a tricyclopentanyl group, a tricyclopentadiene group, and a dicyclopentadiene group; and groups in which these groups are partially substituted with a substituent.
Examples of the substituent include an alkyl group, a cycloalkyl group, an alkylcycloalkyl group, a hydroxyl group, a ketone group, a nitro group, an amine group, and a halogen atom.

From the viewpoints of compatibility with other materials and solubility in alkaline developers, the lower limit of the number of carbon atoms in the bridged cyclic aliphatic group is preferably 5 or more, and particularly preferably 7 or more. The upper limit is preferably 12 or less, and particularly preferably 10 or less.

It is also preferable that the alkali-soluble resin has a maleimide structure represented by the following general formula (6):

[In general formula (6), R ^M represents a hydrocarbon group having an optionally substituted cyclic structure.]

When the alkali-soluble resin has a maleimide structure represented by general formula (6), the hydrocarbon ring contains a nitrogen atom, which provides excellent compatibility with the basic block-type dispersant and basic graft-type dispersant described above, resulting in extremely fast development speeds and minimal development residue.

In general formula (6), R 1 ^M may be an aliphatic hydrocarbon group which may be substituted, or an aromatic hydrocarbon group which may be substituted.
Examples of the former include a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.
Examples of the latter include a phenyl group, a methylphenyl group, an ethylphenyl group, a dimethylphenyl group, a diethylphenyl group, a methoxyphenyl group, a benzyl group, a hydroxyphenyl group, and a naphthyl group.

In addition, it is particularly preferable for the alkali-soluble resin to have both a maleimide structure represented by general formula (6) and a hydrocarbon ring, as this reduces development residue.

It is also preferable that the alkali-soluble resin has a structural unit represented by the following general formula (7):

In the general formula (7), X is a hydrogen atom or a methyl group, and Y is a group having a phenoxyethyl structure represented by the following general formula (8):

[In general formula (8), n is an integer of 1 to 8.]

In the present invention, n in the general formula (8) is preferably 1 to 4, and 2-phenoxyethyl (meth)acrylate, in which n is 1, is particularly preferred.
By using the above-mentioned compounds, the development residue is more favorable and the resolubility is improved.

In the case of alkali-soluble resins containing aliphatic rings, if the development speed is appropriate, the compatible dispersant and colorant will develop together, which tends to reduce development residue.

In the alkali-soluble resin used in the present invention, it is preferable to use an acrylic copolymer having a structural unit having a hydrocarbon ring as described above in addition to a structural unit having a carboxyl group, since this makes it easy to adjust the amount of each structural unit and to increase the amount of the structural unit having a hydrocarbon ring, thereby improving the functionality of the structural unit.
The acrylic copolymer having a carboxyl-containing structural unit and the above-mentioned hydrocarbon ring can be prepared by using an ethylenically unsaturated monomer having a hydrocarbon ring as the aforementioned "other copolymerizable monomer."
Examples of ethylenically unsaturated monomers having a hydrocarbon ring include cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, adamantyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, styrene, N-phenylmaleimide, N-benzylmaleimide, and N-cyclohexylmaleimide. From the viewpoint of excellent water stain suppression effect, phenoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, adamantyl (meth)acrylate, benzyl (meth)acrylate, styrene, and N-phenylmaleimide are preferred, and phenoxyethyl (meth)acrylate and styrene are particularly preferred.

In the present invention, the alkali-soluble resin in the coloring composition has a hydrocarbon ring, and if the alkali-soluble resin contains two or more types of structural units having a hydrocarbon ring (hereinafter, may be referred to as "hydrocarbon ring-containing structural units"), the effects of the present invention may be exhibited synergistically, which is preferable.
The phrase "the alkali-soluble resin contains two or more types of structural units having a hydrocarbon ring" may refer to either a case where an alkali-soluble resin having two or more types of hydrocarbon ring-containing structural units is contained in a coloring composition (Coloring Composition Preparation Examples 26 to 28 described below), or a case where an alkali-soluble resin having two or more types of hydrocarbon rings (at least two of which have structural units different from each other) is contained in a coloring composition (Coloring Composition Preparation Example 30 described below). A plurality of alkali-soluble resins having two or more types of hydrocarbon ring-containing structural units may be used in combination.

<<Polymerizable polyfunctional compound>>
The polymerizable polyfunctional compound is not particularly limited, and known polymerizable polyfunctional compounds can be used.
The "polymerizable polyfunctional compound" is not particularly limited as long as it has two or more polymerizable functional groups in one molecule, and examples thereof include polyfunctional (meth)acrylates such as polyester (meth)acrylate, polyether (meth)acrylate, urethane (meth)acrylate, and epoxy (meth)acrylate; polyfunctional allyl compounds such as diallyl phthalate and triallyl isocyanurate; and the like.

Among these, specific examples of polyether (meth)acrylate include the following:
Examples of bifunctional (meth)acrylates include linear alkanediol di(meth)acrylates such as 1,4-butanediol di(meth)acrylate and 1,6-hexanediol di(meth)acrylate; diethylene glycol di(meth)acrylate, polyethylene glycol #200 di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol #400 di(meth)acrylate; partial (meth)acrylic acid esters of trivalent or higher alcohols such as pentaerythritol di(meth)acrylate; bisphenol-based di(meth)acrylates such as bisphenol A di(meth)acrylate and bisphenol F di(meth)acrylate; neopentyl glycol di(meth)acrylate; and the like.

Examples of trifunctional (meth)acrylates include glycerin tri(meth)acrylate, glycerin PO-modified tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolpropane EO-modified tri(meth)acrylate, trimethylolpropane PO-modified tri(meth)acrylate, isocyanuric acid EO-modified tri(meth)acrylate, isocyanuric acid EO-modified ε-caprolactone-modified tri(meth)acrylate, 1,3,5-triacryloylhexahydro-s-triazine, pentaerythritol tri(meth)acrylate, and dipentaerythritol tri(meth)acrylate tripropionate.

Examples of tetrafunctional or higher (meth)acrylates include pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, succinic acid-modified dipentaerythritol penta(meth)acrylate, succinic acid-modified pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate monopropionate, dipentaerythritol hexa(meth)acrylate, tetramethylolethane tetra(meth)acrylate, and oligoester tetra(meth)acrylate.

These polyfunctional monomers may be used alone or in combination of two or more. For example, a polyfunctional monomer having a carboxy group may be used in combination with a polyfunctional monomer not having a carboxy group. From the viewpoint of improving heat resistance and adhesion, succinic acid modified pentaerythritol tri(meth)acrylate having a carboxy group, succinic acid modified dipentaerythritol penta(meth)acrylate having a carboxy group, etc. are preferred.

<<Polymerization initiator>>
Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator.
The photopolymerization initiator is not particularly limited, and any known photopolymerization initiator conventionally used for radical polymerization can be used. In particular, it is preferable to use a photopolymerization initiator that is generally used for producing color filters.

Specific examples of such photopolymerization initiators include compounds that generate free radicals when exposed to ultraviolet energy, such as benzoin derivatives; benzophenone derivatives; xanthone derivatives or thioxanthone derivatives such as xanthone, diethylthioxanthone, and isopropylthioxanthone; oxime ester compounds such as Irgacure OXE-01 and Irgacure OXE-02 (both manufactured by BASF Japan); and ADEKA OPT-N-1919 (manufactured by Asahi Denka); halogen-containing compounds such as chlorosulfonyl, chloromethyl polynuclear aromatic compounds, chloromethyl heterocyclic compounds, and chloromethyl benzophenones; triazines; fluorenones; haloalkanes; redox couples of photoreducible dyes and reducing agents; organic sulfur compounds; peroxides; and the like.

Specific examples of photopolymerization initiators include aromatic ketone compounds such as Michler's ketone, 4,4'-bisdiethylaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2-ethylanthraquinone, and phenanthrene; benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether; benzoin compounds such as methylbenzoin and ethylbenzoin; 2-(o-chlorophenyl)-4,5-phenylimidazole dimer, 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)imidazole dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2,4,5-triarylimidazole dimer, and 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)imidazole dimer. Biimidazole compounds such as (m-methylphenyl)imidazole dimer; 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone, 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-methoxystyryl)-1,3,4-oxadiazole, etc. halomethylthiazole compounds such as 2,4-bis(trichloromethyl)-6-p-methoxystyryl-s-triazine, 2,4-bis(trichloromethyl)-6-(1-p-dimethylaminophenyl-1,3-butadienyl)-s-triazine, 2-trichloromethyl-4-amino-6-p-methoxystyryl-s-triazine, 2-(naphth-1-yl)-4,6-bis-trichloromethyl-s-triazine, 2- Halomethyl-s-triazine compounds such as (4-ethoxy-naphth-1-yl)-4,6-bis-trichloromethyl-s-triazine and 2-(4-butoxy-naphth-1-yl)-4,6-bis-trichloromethyl-s-triazine; 2,2-dimethoxy-1,2-diphenylethan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone, 1,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,1-hydroxy-cyclohexyl-phenyl ketone, methyl benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl sulfide, benzyl methyl ketal, dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, 2-n-butoxyethyl-4-dimethylaminobenzoate, 2-chlorothioxanthone, 2,4-diethylthio Examples include oxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(o-acetyloxime), 4-benzoylmethyldiphenyl sulfide, 1-hydroxycyclohexylphenyl ketone, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, α-dimethoxy-α-phenylacetophenone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-1-propanone, and 1,2-octadione.

Also, a photopolymerization initiator having a tertiary amine structure can be preferably used. The photopolymerization initiator having a tertiary amine structure has a tertiary amine structure that acts as an oxygen quencher in the molecule, and therefore has the advantage that radicals generated from the photopolymerization initiator are less likely to be deactivated by oxygen, thereby improving sensitivity.
Commercially available photopolymerization initiators having the above tertiary amine structure include, for example, Irgacure 907 and Irgacure 369 (both manufactured by BASF Japan Ltd.), and HiCure ABP (manufactured by Kawaguchi Pharmaceutical Co., Ltd.).

<<<Oxime ester photopolymerization initiators>>>
The coloring composition for color filter of the present invention preferably contains an oxime ester-based photopolymerization initiator.
When a coloring composition for color filters is prepared, the sensitivity (film remaining rate) of the coloring composition is improved by using an oxime ester-based photopolymerization initiator.

The oxime ester photopolymerization initiator can be appropriately selected from compounds described in JP 2000-80068 A, JP 2001-233842 A, JP 2010-527339 A, JP 2010-527338 A, JP 2013-041153 A, WO 2015/036910, etc.

Commercially available oxime ester photopolymerization initiators include IRGACURE OXE-01, IRGACURE OXE-02, IRGACURE OXE-03, IRGACURE OXE-04 (all manufactured by BASF), ADEKA OPT-N-1919, ADEKA ARCLES NCI-930, ADEKA ARCLES NCI-831 (all manufactured by ADEKA), TR-PBG-304, TR-PBG-326, TR-PBG-3057 (all manufactured by Changzhou Strong Electronic New Materials Co., Ltd.), and the like.
Among these, Irgacure OXE-03, Irgacure OXE-04, ADEKA OPT-N-1919, ADEKA Arcles NCI-930, ADEKA Arcles NCI-831, and TR-PBG-304 are particularly preferred because of their high sensitivity.

Specific examples of the oxime ester photopolymerization initiator include the following compounds, namely, compounds of the following formulae (A1) and (B1) to (B7).

Oxime ester photopolymerization initiators may be used alone or in combination of two or more types.

<<<Other photopolymerization initiators>>>
In addition to the oxime ester-based photopolymerization initiator, the coloring composition for color filter of the present invention may further contain an α-aminoketone-based photopolymerization initiator, a biimidazole-based photopolymerization initiator, a thioxanthone-based photopolymerization initiator, an acylphosphine oxide-based photopolymerization initiator, or the like.

An α-aminoketone-based photopolymerization initiator has the property of curing the coating film from the surface to the middle and is likely to suppress deep curing of the coating film, and therefore is preferred in that it is highly likely to improve deep curing of the coating film when combined with the oxime ester-based photopolymerization initiator.
Examples of the α-aminoketone photopolymerization initiator include 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one (e.g., Irgacure 907, manufactured by BASF), 2-benzyl-2-(dimethylamino)-1-(4-morpholinophenyl)-1-butanone (e.g., Irgacure 369, manufactured by BASF), and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (Irgacure 379EG, manufactured by BASF).
The α-aminoketone photopolymerization initiator may be used alone or in combination of two or more thereof. Among these, a combination of 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one and 2-benzyl-2-(dimethylamino)-1-(4-morpholinophenyl)-1-butanone is preferred from the viewpoint of improving the residual film rate.

Biimidazole-based photopolymerization initiators have the property of curing the deep portions of a coating film, and are likely to suppress the surface curability of the coating film. Therefore, when combined with a compound represented by the oxime ester-based photopolymerization initiator, they tend to improve the surface curability of the coating film, making them preferable.
Examples of the biimidazole-based photopolymerization initiator include 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2-bromophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, and 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl. 2,2'-bis(2,4,6-trichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2-bromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-tribromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, and the like can be mentioned.
The biimidazole-based photopolymerization initiator may be used alone or in combination of two or more kinds, and among these, it is preferable to use it in combination with a mercapto compound described below, from the viewpoint of improving the curability of the coating film.
Furthermore, it is preferable to use the oxime ester photopolymerization initiator in combination with a biimidazole photopolymerization initiator and the α-aminoketone photopolymerization initiator, in particular, from the viewpoint of improving the film retention rate and linearity.
The phrase "linearity is improved" means that the colored layer formed in the development step after coating the colored composition has less unevenness at the edge and is formed in a straight line.

Examples of the thioxanthone-based photopolymerization initiator include 2,4-isopropylthioxanthone, 2,4-diethylthioxanthone, 1-chloro-4-propoxythioxanthone, and 2,4-dichlorothioxanthone.
The thioxanthone-based photopolymerization initiator may be used alone or in combination of two or more kinds. Among them, it is preferable to use 2,4-isopropylthioxanthone or 2,4-diethylthioxanthone from the viewpoint of improving transfer of generated radicals.
Furthermore, it is preferable to use the oxime ester photopolymerization initiator in combination with a thioxanthone photopolymerization initiator and the α-aminoketone photopolymerization initiator, in particular, from the viewpoint of improving the residual film rate.

Although acylphosphine oxide-based photopolymerization initiators have the property of being less prone to yellowing due to heat, they generally have low sensitivity and may not provide sufficient curability. However, when combined with the oxime ester-based photopolymerization initiator, they tend to improve the overall curability of the coating film, and are therefore preferred.
Examples of the acylphosphine oxide photopolymerization initiator include benzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyl-diphenylphosphine oxide, 3,4-dimethylbenzoyl-diphenylphosphine oxide, 2,4,6-trimethylbenzoyl-phenylethoxyphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, and bis(2,6-dimethylbenzoyl)-ethylphosphine oxide.
The acylphosphine oxide photopolymerization initiator may be used alone or in combination of two or more kinds. Among them, it is preferable to use bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide from the viewpoint of improving the curability of the coating film.

<<<Mercapto compounds>>>
The coloring composition of the present invention preferably contains a mercapto compound. Mercapto compounds have the property of accepting radicals from slow-reacting radicals and accelerating the reaction, thereby accelerating the curing of the coating surface and suppressing the occurrence of water spots.
Water stains refer to the phenomenon in which traces of water seep into the substrate after rinsing with pure water following alkaline development. These water stains disappear after post-baking and do not pose a problem for the product. However, they are detected as irregularities during visual inspection of the patterned surface after development, making it difficult to distinguish between normal and abnormal products. Therefore, lowering the inspection sensitivity of the inspection equipment used in visual inspection results in a decrease in the yield of the final color filter product, which is problematic.

Examples of mercapto compounds include 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole, 2-mercapto-5-methoxybenzothiazole, 2-mercapto-5-methoxybenzimidazole, 3-mercaptopropionic acid, methyl 3-mercaptopropionate, ethyl 3-mercaptopropionate, octyl 3-mercaptopropionate, 1,4-bis(3-mercaptobutyryloxy)butane, and 1,3,5-tris(3-mercaptobutyryloxy)butane. Examples include (3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), dipentaerythritol hexakis(3-mercaptopropionate), and tetraethylene glycol bis(3-mercaptopropionate).

In particular, polyfunctional mercapto compounds having two or more mercapto groups (-SH groups) in one molecule have a high crosslink density and are extremely effective in suppressing water stains.
Specific examples of polyfunctional mercapto compounds include 1,4-bis(3-mercaptobutyryloxy)butane, 1,3,5-tris(3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), dipentaerythritol hexakis(3-mercaptopropionate), and tetraethylene glycol bis(3-mercaptopropionate).

Furthermore, since the excellent water stain suppression effect is likely to be maintained even when stored for a long period of time, secondary mercapto compounds having a secondary mercapto group in which the carbon atom to which the mercapto group is bonded is a secondary carbon atom are preferred, and polyfunctional secondary mercapto compounds having two or more such secondary mercapto groups in one molecule are even more preferred.

By incorporating an alkali-soluble resin having a hydrocarbon ring into a coloring composition for color filters and further using a mercapto compound, the effect of suppressing the occurrence of water stains is synergistically excellent.

The mercapto compounds may be used alone or in combination of two or more.
When two or more types are used in combination, it is preferable that they contain a polyfunctional mercapto compound and/or a secondary mercapto compound, and it is particularly preferable that they contain a polyfunctional secondary mercapto compound.

In the coloring composition for color filter of the present invention, the total content of the mercapto compounds is not particularly limited as long as the effects of the present invention are not impaired, but is preferably in the range of 0.2 mass % or more and 7 mass % or less, more preferably 0.5 mass % or more and 5 mass % or less, based on the total amount of solids in the coloring composition for color filter.
Within the above range, the occurrence of water stains can be effectively suppressed.

The total content of the photopolymerization initiator used in the coloring composition for color filter of the present invention is not particularly limited as long as the effects of the present invention are not impaired, but is preferably in the range of 0.1 mass % to 16.0 mass % and more preferably 1.0 mass % to 12.0 mass % relative to the total solid content of the coloring composition for color filter. If this content is less than the above lower limit, photocuring does not proceed sufficiently, and the exposed portion may dissolve during development, which may impair the effects of the present invention. On the other hand, if it is more than the above upper limit, the obtained colored layer may undergo strong yellowing and the brightness may decrease.
In the present invention, the solid content refers to everything other than the above-mentioned solvent, including liquid polyfunctional monomers and the like.

The content of the oxime ester photopolymerization initiator used in the coloring composition for color filters of the present invention is preferably in the range of 0.1% by mass or more and 8.0% by mass or less, and more preferably 0.5% by mass or more and 6.0% by mass or less, relative to the total solids content of the coloring composition. If this content is less than the above lower limit, the effects of the present invention may be impaired. On the other hand, if it is more than the above upper limit, the resulting colored layer may exhibit severe yellowing and reduced brightness.

[0047] When an oxime ester photopolymerization initiator and another photopolymerization initiator are used in combination as the photopolymerization initiator used in the present invention, the content of the oxime ester photopolymerization initiator is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 20 parts by mass or more, and still more preferably 30 parts by mass or more, in 100 parts by mass in total of the photopolymerization initiators used in the colored composition of the present invention.
On the other hand, in order to fully exert the combined effect with other photopolymerization initiators, the content of the oxime ester photopolymerization initiator is preferably 90 parts by mass or less, and more preferably 80 parts by mass or less, in 100 parts by mass in total of the photopolymerization initiators used in the colored composition of the present invention.

When the photopolymerization initiator used in the present invention further contains at least one selected from the group consisting of an α-aminoketone-based photopolymerization initiator, a biimidazole-based photopolymerization initiator, a thioxanthone-based photopolymerization initiator, and an acylphosphine oxide-based photopolymerization initiator, the total content of these is preferably in the range of 0.4% by mass or more and 4.0% by mass or less, and more preferably 0.6% by mass or more and 3.0% by mass or less, based on the total solid content of the coloring composition.

When an α-aminoketone-based photopolymerization initiator is combined with a biimidazole-based photopolymerization agent and/or a thioxanthone-based photopolymerization initiator as the photopolymerization initiator used in the present invention, the ratio of the α-aminoketone-based photopolymerization initiator to the biimidazole-based photopolymerization initiator and/or thioxanthone-based photopolymerization initiator is preferably 5 to 60 parts by mass, and more preferably 10 to 40 parts by mass, per 100 parts by mass of the α-aminoketone-based photopolymerization initiator, in order to achieve both coating film curability and pattern shape.

The photopolymerization initiator used in the present invention is not limited to one type, and two or more types may be used in combination.

<<Content ratio>>
[0122] In the coloring composition of the present invention, the content ratio of the alkali-soluble resin to the polymerizable polyfunctional compound is not particularly limited, but from the viewpoints of sensitivity, resolution, and developability, the content of the polymerizable polyfunctional compound relative to 100 parts by mass of the alkali-soluble resin is preferably 0 to 500 parts by mass, more preferably 10 to 300 parts by mass, and particularly preferably 20 to 200 parts by mass.
The content of the alkali-soluble resin is preferably 5 to 80% by mass, more preferably 10 to 40% by mass, relative to the total solid content of the coloring composition, and the content of the polymerizable polyfunctional compound is preferably 5 to 60% by mass, more preferably 10 to 40% by mass, relative to the total solid content.

From the viewpoints of sensitivity, resolution, and developability, the content of the polymerization initiator is typically 3 to 50 parts by weight, preferably 7 to 40 parts by weight, and particularly preferably 10 to 35 parts by weight, per 100 parts by weight of the polymerizable polyfunctional compound.

The content of the coloring material is preferably from 3 to 65% by mass, more preferably from 6 to 55% by mass, and particularly preferably from 10 to 45% by mass, based on the total solid content of the coloring composition.
Within this range, the effects of the present invention can be easily achieved, and in particular, coloring power, sensitivity, resolution, and developability are excellent. In particular, when the colorant liquid of the present invention is used, the concentration of the colorant can be increased up to the above-mentioned upper limit, and therefore, the above-mentioned excellent color filter can be produced.

The content of the solvent is preferably in the range of 55 to 95% by mass, and particularly preferably in the range of 65 to 88% by mass, based on the total amount of the coloring composition including the solvent.
When the content of the solvent is within the above range, excellent coating properties can be achieved.

<<Other ingredients>>
The coloring composition may further contain, as necessary, for example, a surfactant for improving wettability, a leveling agent, a silane coupling agent for improving adhesion, an adhesion promoter, an antifoaming agent, a cissing inhibitor, an antioxidant, an anti-aggregation agent, an ultraviolet absorber, a polymerization terminator, a chain transfer agent, etc.

<<Content of specific metal element in coloring composition>>
The coloring composition for color filter of the present invention is a coloring composition containing the color material liquid of the present invention, a polymerization initiator, and an alkali-soluble resin, characterized in that the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is 120 mass ppm or less with respect to the entire coloring composition.

The total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is preferably as small as possible, regardless of cost, and is preferably 90 ppm by mass or less, more preferably 50 ppm by mass or less, particularly preferably 20 ppm by mass or less, still more preferably 10 ppm by mass or less, and most preferably 3 ppm by mass or less, relative to the entire coloring composition.
When the content is equal to or less than the upper limit, the developability is good while maintaining dispersion stability, and therefore the colorant concentration in the coloring composition and the colorant concentration in the solid content of the coloring composition can be increased, and as a result, a color filter that achieves high color density even with a low film thickness can be obtained.

Coloring compositions that fall within the above metal content range exhibit good dispersion performance, dispersion stability, and solubility, and also exhibit good developability during color filter production.

There is no particular lower limit for the "total mass of calcium (Ca) and iron (Fe) contained in the coloring composition," but it is preferably 0.5 ppm by mass or more, and particularly preferably 1 ppm by mass or more. If it is above the above lower limit, the developability is sufficiently good, so that excessive costs for removing the metal elements are not incurred.

Furthermore, the total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the coloring composition is preferably 135 mass ppm or less relative to the entire coloring composition. That is, it is preferable that the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is 120 mass ppm or less relative to the entire coloring composition, and the total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) is 135 mass ppm or less relative to the entire coloring composition.
By preparing a coloring composition for color filters using the coloring material liquid of the present invention, it is easy to prepare an excellent coloring composition that falls within the above-mentioned metal content range.

The total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the coloring composition is more preferably 60 ppm by mass or less, particularly preferably 30 ppm by mass or less, and even more preferably 20 ppm by mass or less.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

Furthermore, the total mass of magnesium (Mg) and chromium (Cr) contained in the coloring composition is preferably 135 mass ppm or less, more preferably 60 mass ppm or less, particularly preferably 30 mass ppm or less, and even more preferably 20 mass ppm or less.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

Furthermore, "the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition" is the above upper limit or less, and "the total mass of calcium (Ca), iron (Fe), magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the coloring composition" is preferably 200 ppm by mass or less, more preferably 150 ppm by mass or less, particularly preferably 100 ppm by mass or less, even more preferably 50 ppm by mass or less, and most preferably 15 ppm by mass or less, with respect to the entire coloring composition.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

Further, "the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition" is the above upper limit or less, and "the total mass of calcium (Ca), iron (Fe), magnesium (Mg), and chromium (Cr) contained in the coloring composition" is preferably 200 ppm by mass or less, more preferably 150 ppm by mass or less, particularly preferably 100 ppm by mass or less, still more preferably 50 ppm by mass or less, and most preferably 15 ppm by mass or less, with respect to the entire coloring composition.
When the content is equal to or less than the upper limit, the above-described effects of the present invention are particularly exhibited.

<<Principle of action>>
Although the present invention is not limited to a range in which the following principle of action applies, the principle of action that, when the total mass of calcium (Ca) and iron (Fe) (or the total mass of specific metal elements) contained in the coloring composition is too large, the dispersion stability and solubility deteriorate, the developability deteriorates, the development time becomes longer, and development residues are generated is presumed to be as follows.

That is, it is thought that the nitrogen moiety contained in, for example, the a monomer (preferably the constituent unit represented by general formula (1)) in the dispersant adsorbs to the colorant to improve the dispersibility of the colorant, and that the colorant tightly surrounded by the dispersant is more likely to be washed away while remaining adsorbed to the dispersant during development, thereby suppressing the generation of residues derived from the colorant on the substrate.
However, if the total mass of calcium (Ca) and iron (Fe) or the total mass of the specific metal elements is too large near the colorant (if there is too much calcium (Ca), iron (Fe), or the specific metal elements), it is thought that the adsorption of the dispersant to the colorant is hindered, or that a salt-type dispersant or acidic dye derivative that contributes to improving dispersibility interacts with the specific metal element and is therefore unable to contribute to improving dispersibility.

Furthermore, if the total mass of the above-mentioned specific metal elements is too high, as mentioned above, the colorant is not suitably surrounded by the dispersant, and therefore, during development, it becomes difficult for the colorant to be washed away with the developer in the form of "colorant suitably surrounded by the dispersant," making it more likely that residues from the colorant will be generated on the substrate (making development defects more likely to occur).

The coloring composition exhibits developability due to the inclusion of an alkali-soluble resin, but it is also considered that the "salt-type dispersant that does not suitably surround the coloring material" reduces the developability. In addition, the influence of cations of the specific divalent or higher metal element on the alkali-soluble resin is also considered.
It is thought that the impact on the deterioration of the above-mentioned developability may be greater for divalent ^or higher cations such as cations of specific metal elements (total amount of divalent or higher cations only, content including ^trivalent cations) than for monovalent cations such as sodium ions (Na + ) and potassium ions (K + ).

For this reason, it is believed that the colored composition obtained using a colorant dispersion liquid with good dispersibility stability has good developability.

<<Preparation of Coloring Composition for Color Filter>>
The coloring composition of the present invention can be prepared by a method in which at least an alkali-soluble resin and a polymerization initiator are blended with a colorant, and if necessary, a polymerizable polyfunctional compound and “other components”, and further, if necessary, a solvent is blended and mixed.
The coloring composition of the present invention is used by preparing a coloring material solution in advance, so that aggregation of the coloring material can be effectively prevented and the coloring material can be dispersed uniformly.

Furthermore, the colorant liquid of the present invention can be set to a high colorant concentration while maintaining a suitable viscosity range, dispersion stability, and solubility. Therefore, the colored composition of the present invention obtained using the colorant liquid of the present invention can also achieve a high colorant concentration while maintaining a suitable viscosity range, dispersion stability, and solubility.

<Color filter>
A color filter usually has a transparent substrate, a light-shielding portion, and a colored layer. The color filter obtained using the colored composition of the present invention can achieve high colorant concentration, high color rendering properties, high contrast, etc., and also has excellent developability during production of the color filter.

<<Colored layer>>
The colored layer is not particularly limited as long as it is formed by curing the colored composition of the present invention described above, but is usually formed in the opening of the light-shielding part on the transparent substrate described below, and is composed of a colored pattern of three or more colors depending on the type of color material contained in the colored composition.
The arrangement of the colored layers is not particularly limited, and may be, for example, a general arrangement such as a stripe type, a mosaic type, a triangle type, a four-pixel arrangement type, etc. The width, area, etc. of the colored layers may be set arbitrarily.

The thickness of the colored layer can be controlled by adjusting the coating method, coating conditions, solid content of the colored composition, viscosity, etc., but is usually in the range of 1 to 5 μm.
When the colorant liquid or coloring composition of the present invention is used, the colorant concentration in the solid content is high, and depending on the composition, it is possible to reduce the thickness (for example, to 80 to 50%) compared to conventional thicknesses. As a result, it is possible to achieve effects such as high color rendering, no color mixing, and high resolubility, which results in less generation of foreign matter and high productivity.

The colored layer can be formed, for example, by the following method.
First, the coloring composition of the present invention described above is applied onto a transparent substrate described later using a coating means such as spray coating, dip coating, bar coating, roll coating, spin coating, or die coating to form a wet coating film.
Next, the wet coating film is dried using a hot plate, an oven, or the like, and then exposed to light through a mask having a predetermined pattern to cause a photopolymerization reaction of the alkali-soluble resin and the polymerizable polyfunctional compound.
Examples of light sources used for exposure include ultraviolet light from low-pressure mercury lamps, high-pressure mercury lamps, extra-high-pressure mercury lamps, metal halide lamps, and the like, and electron beams.
After the exposure, a heat treatment may be carried out to promote the polymerization reaction.

Next, the coating is developed using a developer to dissolve and remove the unexposed portions, thereby forming a coating film in a desired pattern. As the developer, a solution in which an alkali is dissolved in water or a water-soluble solvent is usually used. The colorant liquid and coloring composition of the present invention have extremely excellent developability.
After the development treatment, the developer is usually washed away and the cured coating film of the resin composition is dried to form a colored layer. After the development treatment, a heat treatment may be carried out to sufficiently cure the coating film.

<<Light-shielding section>>
The light-shielding portion of the color filter is formed in a pattern on a transparent substrate, which will be described later.
The pattern shape of the light-shielding portion is not particularly limited, and examples thereof include stripe shapes and matrix shapes.
Examples of the light-shielding portion include a black coloring material dispersed or dissolved in a binder resin, a metal thin film of chromium, chromium oxide, etc. The metal thin film may be a two-layer laminate of a CrOx film (x is an arbitrary number) and a Cr film.

When the light-shielding portion is formed by dispersing or dissolving a black colorant in a binder resin, examples of methods for forming the light-shielding portion include photolithography, printing, and inkjet printing using a resin composition for the light-shielding portion.

In the above case, when photolithography is used as a method for forming the light-shielding portion, a photosensitive resin having a reactive vinyl group, such as an acrylate-based, methacrylate-based, polyvinyl cinnamate-based, or cyclized rubber-based resin, is used as the binder resin.
In this case, a photopolymerization initiator, a sensitizer, a coating property improver, a development improver, a crosslinking agent, a polymerization inhibitor, a plasticizer, a flame retardant, etc. may be added to the resin composition for the light-shielding part, which contains a black pigment such as carbon black or titanium black as a pigment (coloring material) and a photosensitive resin.

On the other hand, when the light-shielding portion is a metal thin film, examples of methods for forming this light-shielding portion include a method in which a metal thin film formed in a vacuum by vapor deposition, sputtering, or the like, is then subjected to metal etching using a resist pattern formed on the metal thin film by photolithography as a mask.

The film thickness of the light-shielding portion is set to approximately 0.05 to 0.4 μm in the case of a thin metal film, and approximately 0.5 to 3 μm in the case of a black colorant dispersed or dissolved in a binder resin.

<<Transparent substrate>>
The transparent substrate in the color filter is not particularly limited as long as it is a base material that is transparent to visible light, and a transparent substrate that is commonly used in color filters can be used. Specific examples include transparent rigid materials that are not flexible, such as quartz glass, alkali-free glass, and synthetic quartz plates, and transparent flexible materials that are flexible, such as transparent resin films and optical resin plates.
The thickness of the transparent substrate is not particularly limited, but may be, for example, about 100 μm to 1 mm depending on the application.
The color filter of the present invention may further include, in addition to the transparent substrate, the light-shielding portion, and the colored layer, an overcoat layer, a transparent electrode layer, an alignment film, a columnar spacer, and the like.

<Display device>
Another aspect of the present invention is a display device comprising the above-described color filter. The display device is not particularly limited, but examples thereof include a liquid crystal display and an organic EL display.
A color filter obtained by using a coloring composition containing the colorant liquid of the present invention is suitably used in display devices such as liquid crystal displays and organic EL displays.
The application of color filters to liquid crystal displays and organic EL displays is generally carried out by known methods.

The present invention will be explained in more detail below using experimental examples, but the present invention is not limited to these examples as long as they do not depart from the gist of the invention.

Preparation Example 1
<Preparation of Dispersant A (Dispersant Solution A)>
<<Synthesis of Block Copolymer A>>
A 500 mL four-neck separable flask was dried under reduced pressure, and the inside of the flask was replaced with argon (Ar).
Under argon flow, 100 g of dehydrated tetrahydrofuran (THF), 2.0 g of methyltrimethylsilyldimethylketene acetal, 0.15 mL of a 1 M acetonitrile solution of tetrabutylammonium 3-chlorobenzoate (TBACB), and 0.2 g of mesitylene were added and mixed by stirring.
To this, 36.7 g of methyl methacrylate was added dropwise over 45 minutes using a dropping funnel. As the reaction progressed, heat was generated, so the temperature was kept below 40°C by ice cooling. After 1 hour, 13.3 g of dimethylaminoethyl methacrylate (DMAEMA) as the "monomer a" was added dropwise over 15 minutes. After reacting for 1 hour, 5 g of methanol was added to stop the reaction.

The solvent was removed under reduced pressure to obtain a block copolymer A.
The mass average molecular weight determined by GPC measurement (NMP, LiBr 10 mM) was 6000. The amine value was 95 mg KOH/g.
The obtained block copolymer A was dissolved in propylene glycol monomethyl ether acetate (PGMEA) to prepare a 60% by mass block copolymer solution.

<<Step of Converting Block Copolymer into a Salt (Step of Preparing Basic Block-Type Dispersant)>>
Next, in a 100 mL round-bottom flask, 23.76 parts by mass of PGMEA and 5.0 parts by mass of the block copolymer solution obtained above were mixed, and 0.94 parts by mass (0.5 molar equivalents relative to the DMAEMA units of the block copolymer) of phenylphosphonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), a salt-forming component, was added, and the mixture was stirred at a reaction temperature of 40°C for 2 hours to obtain "Dispersant A," which was further diluted appropriately with PGMEA to prepare "Dispersant Solution A" with a solids content of 20% by mass.

Preparation Example 2
<Preparation of Dispersant B (Dispersant Solution B)>
<<Synthesis of Block Copolymer B>>
A 500 mL round-bottom, four-neck separable flask equipped with a condenser, an addition funnel, a nitrogen inlet, a mechanical stirrer, and a digital thermometer was charged with 250 parts by mass of dehydrated tetrahydrofuran (THF) and 0.6 parts by mass of lithium chloride, and the inside of the flask was thoroughly purged with nitrogen.
After the reaction flask was cooled to −60° C., 4.9 parts by mass of butyllithium (15% by mass hexane solution), 1.1 parts by mass of diisopropylamine, and 1.0 part by mass of methyl isobutyrate were injected using a syringe.

As the "b monomer", 2.2 parts by mass of 1-ethoxyethyl methacrylate (EEMA), 18.7 parts by mass of 2-hydroxyethyl methacrylate (HEMA), 12.8 parts by mass of 2-ethylhexyl methacrylate (EHMA), 13.7 parts by mass of n-butyl methacrylate (BMA), 9.5 parts by mass of benzyl methacrylate (BzMA), and 17.5 parts by mass of methyl methacrylate (MMA) were added dropwise over 60 minutes using an addition funnel.
After 30 minutes, 26.7 parts by mass of dimethylaminoethyl methacrylate (DMAEMA), the "monomer a", was added dropwise over 20 minutes.

After reacting for 30 minutes, 1.5 parts by mass of methanol was added to terminate the reaction. The resulting precursor block copolymer THF solution was reprecipitated in hexane, purified by filtration and vacuum drying, and diluted with PGMEA to obtain a solution with a solid content of 30% by mass.
32.5 parts by mass of water was added, and the temperature was raised to 100° C., followed by reaction for 7 hours, whereby the EEMA-derived structural units were deprotected to form methacrylic acid (MAA)-derived structural units.
The obtained block copolymer PGMEA solution was reprecipitated in hexane, filtered, and purified by vacuum drying to obtain a block copolymer B containing an "A block containing a constitutional unit represented by general formula (1)" and a "B block containing a constitutional unit derived from a carboxy group-containing monomer and having solvent-philicity."

The block copolymer B had an acid value of 8 mgKOH/g and a Tg of 38°C.
The obtained block copolymer B was analyzed by gel permeation chromatography (GPC), and it was found that the weight average molecular weight Mw was 7730. The amine value was 95 mgKOH/g.

<<Step of Converting Block Copolymer into a Salt (Step of Preparing Basic Block-Type Dispersant)>>
Next, a salt was formed in the same manner as in Preparation Example 1 to prepare "Dispersant B," which was then diluted with PGMEA to prepare "Dispersant Solution B" with a solid content of 20 mass %.
As in Preparation Example 1, phenylphosphonic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), a salt-forming component, was added in an amount of 0.5 molar equivalents relative to the "DMAEMA unit, which is the monomer a" of the block copolymer B.

Preparation Example 3
<Organic pigment purification>
2.0 parts by mass of the organic pigment (R-1) shown in Table 1 and 100 parts by mass of ion-exchanged water were placed in a beaker, and the mixture was stirred batchwise with an ultrasonic homogenizer for 10 minutes while maintaining the temperature at 30°C, and then filtered using the following filter paper.
Manufacturer/distributor: ADVANTEC
Product name: Fikter Paper Quantitative Ashless
Standard: 5C, 150mm (100CIRCLES)

A method in which the above-mentioned washing (water washing) process was performed twice was designated "Purification Method 1" (Colorant Dispersion Liquid Preparation Example 1), a method in which it was performed 20 times was designated "Purification Method 2" (Colorant Dispersion Liquid Preparation Example 2), and a method in which it was performed 30 times was designated "Purification Method 3" (Colorant Dispersion Liquid Preparation Example 3, Colorant Dispersion Liquid Preparation Example 9).

Furthermore, 2.0 parts by mass of the organic pigment (R-1) shown in Table 1 was used, and a Nutsche funnel was used to continuously run 30,000 parts by mass of ion-exchanged water through the funnel for 15 minutes, followed by washing (water washing) by suction filtration using a continuous method. Then, filtration was carried out using the above filter paper.
The temperature of the ion-exchanged water that was passed was 30° C. This method was designated as “Purification Method 4” (Colorant Dispersion Liquid Preparation Example 4).

Purification methods 1-4 were used to prepare purified organic pigments.
In Colorant Dispersion Liquid Preparation Examples 5 to 8 and Colorant Dispersion Liquid Preparation Examples 101 to 103, the organic pigment was not purified.
Using the obtained (purified) organic pigments, colorant dispersions were prepared as in the following Colorant Dispersion Preparation Examples 1 to 9 and Colorant Dispersion Preparation Examples 101 to 103.

Preparation Example 4
<(4-1) Synthesis of Resin 1>
A mixed solution of 40 parts by mass of BzMA, 15 parts by mass of MMA, 25 parts by mass of MAA, and 3 parts by mass of AIBN was added dropwise to a polymerization vessel containing 150 parts by mass of PGMEA under a nitrogen stream at 100° C. over 3 hours. After completion of the addition, the mixture was further heated at 100° C. for 3 hours to obtain a polymer solution.
The weight average molecular weight of the polymer in this polymer solution was 7,000.

Next, 20 parts by mass of GMA, 0.2 parts by mass of triethylamine, and 0.05 parts by mass of p-methoxyphenol were added to the obtained polymer solution, and the mixture was heated at 110°C for 10 hours to react the carboxyl group of the methacrylic acid in the main chain with the epoxy group of GMA, thereby synthesizing Resin 1.
During the reaction, air was bubbled through the reaction solution to prevent polymerization of GMA, and the reaction was monitored by measuring the acid value of the solution.

The resulting resin, Resin 1, was a resin in which side chains containing ethylenic double bonds were introduced using GMA into the main chain of a polymer formed by copolymerization of BzMA, MMA, and MAA, and had a solids content of 40% by mass, an acid value of 74 mg KOH/g, and a weight-average molecular weight of 12,000.

<<Name of abbreviation>>
BzMA Benzyl methacrylate MMA Methyl methacrylate MAA Methacrylic acid GMA Glycidyl methacrylate AIBN Azobisisobutyronitrile PGMEA Propylene glycol monomethyl ether acetate

<(4-2) Synthesis of Resin 2>
Resin 2 was obtained in the same manner as in (4-1) above, except that 40 parts by mass of cyclohexyl methacrylate was used instead of 40 parts by mass of BzMA.
The resulting resin 2 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

<(4-3) Synthesis of Resin 3>
Resin 3 was obtained in the same manner as in (4-1) above, except that 40 parts by mass of styrene was used instead of 40 parts by mass of BzMA.
The resulting resin 3 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

<(4-4) Synthesis of Resin 4>
Resin 4 was obtained in the same manner as in (4-1) above, except that 40 parts by mass of dicyclopentanyl methacrylate was used instead of 40 parts by mass of BzMA.
The resulting resin 4 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

<(4-5) Synthesis of Resin 5>
Resin 5 was obtained in the same manner as in (4-1) above, except that 40 parts by mass of N-phenylmaleimide (Tokyo Chemical Industry Co., Ltd.) was used instead of 40 parts by mass of BzMA.
The resulting resin 5 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

<(4-6) Synthesis of Resin 6>
Resin 6 was obtained in the same manner as in (4-1) above, except that "20 parts by mass of styrene and 20 parts by mass of N-phenylmaleimide (Tokyo Chemical Industry Co., Ltd.)" were used instead of "40 parts by mass of BzMA" in (4-1).
The resulting resin 6 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

<(4-7) Synthesis of Resin 7>
Resin 7 was obtained in the same manner as in (4-1) above, except that 40 parts by mass of phenoxyethyl methacrylate was used instead of 40 parts by mass of BzMA.
The resulting resin 7 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

<(4-8) Synthesis of Resin 8>
Resin 8 was obtained in the same manner as in (4-1) above, except that 40 parts by mass of hydroxyethyl methacrylate was used instead of 40 parts by mass of BzMA.
The resulting resin 8 had a solid content of 40% by mass, an acid value of 74 mgKOH/g, and a weight average molecular weight of 12,000.

Preparation Example 5
<Synthesis of acidic dye derivatives>
374.76 parts by mass of fuming sulfuric acid having a sulfur trioxide content of 11% by mass was stirred while being cooled to 10° C., and 74.96 parts by mass of CI Pigment Yellow 138 was added thereto. The mixture was then stirred for 6 hours at 90° C. The resulting reaction liquid was added to 1600 parts by mass of ice water, and the mixture was stirred for 15 minutes, after which the precipitate was filtered.
The obtained wet cake was washed three times with 800 parts by mass of demineralized water. The washed wet cake was dried in vacuum at 80°C to obtain a sulfonated yellow pigment derivative, which is an acidic dye derivative. The molecular weight was measured by TOF-MS, and it was confirmed to be the synthetic target product.

<Preparation of colorant liquid>
Coloring material dispersion preparation example 1
16.7 parts by mass of "PGMEA solution with a solid content of 40% by mass of resin 1 (BzMA/MMA/MAA/GMA = 40/15/25/20 (mass ratio), weight average molecular weight 12000)" obtained in Preparation Example 4, 8.1 parts by mass of dispersant solution A, and 62.2 parts by mass of PGMEA were stirred and mixed with a dissolver to uniformly dissolve them.

To this solution, 12.7 parts by mass of the (purified) organic pigment obtained in Preparation Example 3 and 0.3 parts by mass of the acidic dye derivative obtained in Preparation Example 5 were added, and 100 parts by mass of zirconia beads having a particle size of 2.0 mm were placed in a mayonnaise bottle, followed by shaking for 1 hour using a paint shaker (manufactured by Asada Iron Works Co., Ltd.) as pre-crushing.
Next, the zirconia beads with a particle size of 2.0 mm were removed, and 200 parts by mass of zirconia beads with a particle size of 0.1 mm were added, and similarly, main disintegration was carried out using a paint shaker for 4 hours to prepare a red colorant dispersion.

Coloring material dispersion preparation examples 2 to 7, 9
The colorant and dispersant were changed as shown in Table 1, and the (purified) organic pigment obtained in Preparation Example 3 was used to prepare colorant dispersions of Colorant Dispersion Preparation Examples 2 to 7 and 9 in the same manner as in Colorant Dispersion Preparation Example 1. In Colorant Dispersion Preparation Examples 5 to 8, the organic pigments used themselves contained a small amount of the specific metal element, so washing with water was not performed.

Coloring material dispersion preparation example 8
A green colorant dispersion was prepared in the same manner as in Colorant Dispersion Preparation Examples 1 to 7, except that the colorant was (G-1) as shown in Table 1 and Dispersant A (Dispersant Solution A) was changed to BYK21116 (a basic block-type dispersant manufactured by BYK Japan KK) (the same mass as Dispersant A and Dispersant B was used in terms of solid content). In Colorant Dispersion Preparation Example 8, the organic pigment (G-1) used itself had a small content of the specific metal element, so washing with water was not performed.

Coloring material dispersion preparation example 10
To a flask, 100 parts by mass of Acid Red 289 (AR289; xanthene dye, manufactured by Tokyo Chemical Industry Co., Ltd.) purified by the "Purification Method 4" was added, and 1,000 parts by mass of methanol was added and dissolved using a magnetic stirrer. After confirming dissolution, 29.9 parts by mass of concentrated hydrochloric acid was added and stirred, converting the sulfonate salt of AR289 into a sulfo group. 1,000 parts by mass of PGMEA was further added to this solution. Next, 276 parts by mass of Dispersant A was added and stirred. Thereafter, a reflux condenser was connected, and the mixture was heated to 80°C in a water bath. After reaching 80°C, the mixture was allowed to react for 4 hours. Thereafter, the methanol was distilled off using an evaporator at 45°C in a water bath, and 1,000 parts by mass of PGMEA was added, followed by cooling and leaving to stand at room temperature for 16 hours. Next, the precipitate was filtered off, the filtered product was washed with about 100 parts by mass of PGMEA, and the obtained filtrate was recovered to obtain a colorant dispersion liquid of Colorant Dispersion Liquid Preparation Example 10 in which the dye was uniformly dispersed.
The particle size distribution was measured using a Microtrac UPA particle size distribution analyzer (manufactured by Nikkiso Co., Ltd.) Evaluation was performed at a 50% average particle size, and the result of volume conversion (MV) was 78 nm.

Colorant Solution Preparation Example 11
A colorant solution was prepared by dissolving 21.3 parts by mass of dye (Y-2) (C.I. Solvent Yellow 162) in 100 parts by mass of diacetone alcohol. The dye (Y-2) used was purified by recrystallization using a mixed solvent of water and acetone (water:acetone=50:50 by mass ratio), and then filtered.

Coloring material dispersion preparation examples 101 to 103
Colorant dispersion liquids of Colorant Dispersion Liquid Preparation Examples 101 to 103 were prepared in the same manner as in Colorant Dispersion Liquid Preparation Example 1, except that the colorant was changed as shown in Table 1 and an "organic pigment that was not the purified organic pigment purified as in Preparation Example 3" was used (except that the organic pigment was not purified).

<Preparation of Color Composition for Color Filter>
Colored composition preparation examples 11-19, 111-113
In Coloring Composition Preparation Examples 11 to 19, the colorant dispersions of Colorant Dispersion Preparation Examples 1 to 9 were used, respectively, and in Coloring Composition Preparation Examples 111 to 113, the colorant dispersions of Colorant Dispersion Preparation Examples 101 to 103 were used, respectively. The solid content concentration was adjusted with PGMEA as necessary, and the components were mixed in the composition shown below to prepare coloring compositions for color filters.

Colorant dispersions (solid content: 21.3% by mass) prepared in Colorant Dispersion Liquid Preparation Examples 1 to 9 and Colorant Dispersion Liquid Preparation Examples 101 to 103: 52.7 parts by mass each; The same resin as Resin 1 used in Colorant Dispersion Liquid Preparation Example 1 was used as an "alkali-soluble resin", and the alkali-soluble resin: 3.04 parts by mass; Polymerizable polyfunctional compound (Aronix M-403, photocurable polyfunctional monomer, manufactured by Toagosei Co., Ltd.): 2.84 parts by mass; Photopolymerization initiator (Irgacure 907, photopolymerization initiator, manufactured by BASF Corporation): 0.89 parts by mass; Surfactant (Megafac F-559, manufactured by DIC Corporation): 0.03 parts by mass; PGMEA: 40.5 parts by mass; Silane coupling agent (KBM-503, manufactured by Shin-Etsu Silicones Co., Ltd.): 0.2 parts by mass

Colored composition preparation example 21
A colored composition for color filter was prepared in the same manner as in Colored Composition Preparation Example 17, except that the following (Change 1) and (Change 2) were changed in Colored Composition Preparation Example 17.

(Change 1)
Instead of "0.89 parts by mass of photopolymerization initiator (manufactured by BASF, Irgacure 907, photopolymerization initiator)", the following photopolymerization initiator and mercapto compound were used.
Photopolymerization initiator (manufactured by ADEKA Corporation, NCI-831): 0.36 parts by mass Photopolymerization initiator (manufactured by BASF Corporation, Irgacure 369): 0.27 parts by mass Photopolymerization initiator (manufactured by BASF Corporation, Irgacure 907): 0.27 parts by mass Pentaerythritol tetrakis(3-mercaptopropionate) (manufactured by SC Organic Chemicals, PEMP): 0.18 parts by mass

(Change 2)
As the solvent, "27.9 parts by mass of PGMEA and 12.6 parts by mass of 3-methoxy-3-methyl-1-butyl acetate (product name: Solfit AC, manufactured by Kuraray)" was used instead of "40.5 parts by mass of PGMEA."

Colored composition preparation examples 22 to 26, 32
Colored compositions for color filters were prepared in the same manner as in Colored Composition Preparation Example 21, except that the alkali-soluble resin was changed as shown in Table 3.

Colored composition preparation examples 27-28
Colored compositions for color filters were prepared in the same manner as in Colored Composition Preparation Example 26, except that the mercapto compound was changed as shown in Table 3.

Colored composition preparation example 29
A colored composition for color filter was prepared in the same manner as in Colored Composition Preparation Example 21, except that pentaerythritol tetrakis(3-mercaptopropionate) was not used.

Colored composition preparation example 30
A colored composition for color filter was prepared in the same manner as in Colored Composition Preparation Example 21, except that a mixture of Resin 3 and Resin 5 was used instead of Resin 1 as the alkali-soluble resin.
Resin 3:Resin 5 were used in a mass ratio of 50:50.

Colored composition preparation example 31
A coloring composition for color filter was prepared in the same manner as in Coloring Composition Preparation Example 21, except that the coloring material dispersion prepared in Coloring Material Dispersion Liquid Preparation Example 10 was used instead of the coloring material dispersion prepared in Coloring Material Dispersion Liquid Preparation Example 7.

Colored composition preparation example 33
Colored compositions for color filters were prepared in the same manner as in Colored Composition Preparation Example 21, except that the photopolymerization initiator in Colored Composition Preparation Example 21 was changed as shown in Table 3.

Colored composition preparation example 34
A coloring composition for color filter was prepared in the same manner as in Coloring Composition Preparation Example 21, except that the coloring material solution prepared in Coloring Material Solution Preparation Example 11 was used instead of the coloring material dispersion liquid prepared in Coloring Material Dispersion Liquid Preparation Example 7.

Colored composition preparation example 121
Colored compositions for color filters were prepared in the same manner as in Colored Composition Preparation Example 27, except that the alkali-soluble resin was changed as shown in Table 3.

Colored composition preparation example 122
In Coloring Composition Preparation Example 111, except that the following (Change 1') and the above-mentioned (Change 2) were changed, a coloring composition for color filter was prepared in the same manner as in Coloring Composition Preparation Example 111.

(Change 1')
Instead of "0.89 parts by mass of photopolymerization initiator (manufactured by BASF, Irgacure 907, photopolymerization initiator)", the photopolymerization initiator shown below was used.
Photopolymerization initiator (manufactured by ADEKA Corporation, NCI-831): 0.36 parts by mass Photopolymerization initiator (manufactured by BASF Corporation, Irgacure 369): 0.27 parts by mass Photopolymerization initiator (manufactured by BASF Corporation, Irgacure 907): 0.27 parts by mass

Measurement example: Quantitative determination of metals in colorant liquid
Using an ICP (Inductively Coupled Plasma) optical emission spectrometer (Vista-PRO, manufactured by Varian), the contents of calcium (Ca), iron (Fe), magnesium (Mg), aluminum (Al), and chromium (Cr) in the colorant liquid (colorant dispersion liquid or colorant solution) were quantified.
The measurement sample was prepared as follows: Approximately 1 g (0.5 to 1.5 g) of the colorant liquid was weighed out, heated over a burner and in an electric furnace (700°C), and incinerated, after which dilute aqua regia was added and the mixture was heated on a hot plate to dissolve.
The resulting solution was diluted with ultrapure water to a total weight of 50,000 g, which was used as a measurement sample.

The detection limit of ICP atomic emission spectrometry in the present invention is less than 0.01 ppm.
In Tables 1 to 3, "0 ppm by mass" means that the value is rounded to the nearest "1" and is therefore less than 0.5 ppm by mass. As described above, the measurement sample was diluted approximately 50 times, so "0" in the tables indicates that the value is below the detection limit of the measurement device.

Evaluation example <Method for evaluating the "dispersion stability" of colorant dispersion liquid>
The colorant dispersion liquids prepared in the Colorant Dispersion Liquid Preparation Examples were stored at room temperature (25°C), and the viscosity was measured one day and one month after storage from the preparation. The viscosity was measured at 25.0±1.0°C using a vibration viscometer (VM-200T2, manufactured by Sekonic Corporation), and the value measured 30 seconds after the start of the measurement was used.

<<Judgment criteria>>
The viscosity measured one day after preparation was compared with the viscosity measured one month after storage, and the results were evaluated as follows:
AA: Viscosity change is within 3% A: Viscosity change is more than 3% but within 5% B: Viscosity change is more than 5% but within 7% C: Viscosity change is more than 7% but within 10% D: Viscosity change is more than 10%

The results are shown in Table 1. If the viscosity change is within 7%, that is, if the "dispersion stability" is "B" or higher, the stability is evaluated as excellent and at a practical level.

<Method for evaluating the "optical properties" of a coloring composition for color filters>
The colored composition obtained in each colored composition preparation example was applied to a glass substrate (manufactured by NH Technoglass Co., Ltd., "NA35") using a spin coater so that the desired color after post-baking was achieved (red colored layer: x = 0.650 with C light source, green colored layer: y = 0.450, yellow colored layer: y = 0.500). After heating and drying for 3 minutes on an 80 ° C hot plate, the coating was irradiated with ultraviolet light at 60 mJ / cm ² using an ultra-high pressure mercury lamp, and then post-baked for 25 minutes in a clean oven at 230 ° C.

The contrast, chromaticity (x, y), and luminance (Y) of the obtained colored film were measured. The contrast was measured using a "Contrast Measuring Instrument CT-1B" manufactured by Tsubosaka Electric Co., Ltd., and the chromaticity and luminance were measured using a "Microspectrophotometer OSP-SP200" manufactured by Olympus Corporation.
The results are shown in Tables 2 to 5.

<<Judgment criteria>>
The contrast is evaluated as excellent if it is 12,000 or more for the red colored layer, 18,000 or more for the green colored layer, or 10,000 or more for the yellow colored layer.

<Method for evaluating "drying unevenness" of coloring composition for color filter>
The coloring composition for color filters was applied to a glass substrate using a die coater, and then vacuum baked until the vacuum reached 0.2 torr to form a coating film with a thickness of 2.0 μm. The obtained substrate was then observed using an interference fringe inspection lamp (Na lamp), and the presence or absence of drying unevenness occurring in the coating film was visually evaluated.

<<Judgment criteria>>
AA: No drying irregularities are observed.
A: Slight drying irregularities are observed.
B: A lot of drying irregularities are observed.

<Method 1 for evaluating the “developability” of a coloring composition for color filters (development rate)>
The colored composition for color filter obtained in each of the colored composition preparation examples was applied onto a glass substrate using a spin coater, and then dried at 80° C. for 3 minutes using a hot plate.
This colored layer was exposed to ultraviolet light of 60 mJ/ ^cm2 using an ultra-high pressure mercury lamp through a photomask with an independent fine line pattern having a line width of 1 μm to 100 μm, thereby forming a colored layer of 2.0 μm in thickness on the glass substrate.

Next, the substrate was spin-developed using a 0.05% by mass aqueous solution of potassium hydroxide (KOH) as the developer, and after contact with the developer, it was rinsed with pure water for development, forming a pattern, and the developability was evaluated.

In the above development process, the time until the unexposed areas were dissolved and removed was measured. The completion of development was visually observed, and the development time was judged according to the following criteria.

<<Judgment criteria>>
AA: Less than 40 seconds A: 40 seconds or more but less than 60 seconds B: 60 seconds or more but less than 80 seconds C: 80 seconds or more but less than 120 seconds D: 120 seconds or more

The results are shown in Tables 2 and 3.
If the development time is less than 40 seconds (AA), the "development speed" is particularly excellent, if the development time is 40 seconds or more but less than 60 seconds (A), the "development speed" is even better, and if the development time is 60 seconds or more but less than 80 seconds (B), the "development speed" is excellent; all of AA, A, and B are judged to be good and at a practical level.
On the other hand, if the development time is 80 seconds or more (C, D), the "development speed" is poor and it is judged that it is not at a practical level.

<Method 2 for evaluating the “developability” of a coloring composition for color filters (development residue)>
The photosensitive colored resin composition for color filters obtained in each colored composition preparation example was applied to a glass substrate using a spin coater, and then dried at 60 ° C. for 3 minutes using a hot plate to form a colored layer with a thickness of 2.5 μm. The glass plate on which the colored layer was formed was shower-developed for 60 seconds using a 0.05 mass % potassium hydroxide aqueous solution as an alkaline developer. The unexposed area (50 mm × 50 mm) of the glass substrate after the colored layer was formed was visually observed, and then thoroughly wiped with a lens cleaner (manufactured by Toray Industries, Inc., product name: Toraysee MK Clean Cloth) containing ethanol, and the degree of coloring of the lens cleaner was visually observed.

<<Judgment criteria>>
AA: No development residue was observed by visual inspection, and the lens cleaner was not discolored at all. A: No development residue was observed by visual inspection, and slight discoloration of the lens cleaner was observed. B: A slight development residue was observed by visual inspection, and slight discoloration of the lens cleaner was observed. C: Development residue was observed by visual inspection, and discoloration of the lens cleaner was observed.

The results are shown in Tables 2 and 3.
If the result of the evaluation is A, B or C, the product can be used in practice, but if the result of the evaluation is B or even A, the product is more effective.

<Method for evaluating “resolubility” of colored composition for color filter>
The tip of a glass substrate measuring 0.5 cm in width and 10 cm in length was immersed in the coloring composition for color filters, and the composition was applied to a 1 cm portion of the glass substrate. The glass substrate was then placed in a thermo-hygrostat so that the glass surface was horizontal, and dried at a temperature of 23°C and a humidity of 80% RH for 30 minutes. Next, the glass substrate with the dried coating film attached was immersed in PGMEA for 15 seconds. The redissolution state of the dried coating film was visually determined and evaluated. The results are also shown in Table 3.

<<Judgment criteria>>
AA: The dried coating film dissolved completely. A: Thin flakes of the dried coating film appeared in the solvent, and these flakes eventually dissolved. B: Thin flakes of the dried coating film appeared in the solvent, and the solution became discolored. C: Thin flakes of the dried coating film appeared in the solvent, and the solution did not become discolored. If the result is AA, A, or B, the product can be used without any problems in practical use.

<Method for evaluating "water stains" of coloring compositions for color filters>
The colored composition for color filters obtained in each colored composition preparation example was applied to a glass substrate using a spin coater in a film thickness that would form a colored layer with a thickness of 1.6 μm after post-baking, and then dried using a hot plate at 60° C. for 3 minutes, and then irradiated the entire surface with ultraviolet light of 60 mJ/cm ² using an ultra-high pressure mercury lamp without using a photomask, thereby forming a colored layer on the glass substrate. Next, spin development was performed using 0.05 wt % potassium (KOH) as a developer, and the substrate was developed by indirectly immersing in the developer for 60 seconds and then washing with pure water, and the washed substrate was rotated for 10 seconds and the water was centrifuged off, and immediately thereafter the contact angle of pure water was measured as described below to evaluate water stains.
The contact angle of pure water was measured by dropping a 1.0 μL droplet of pure water onto the surface of the colored layer immediately after the water had been removed by centrifugation, and measuring the static contact angle 10 seconds after the drop had landed according to the θ/2 method using a contact angle meter DM 500 manufactured by Kyowa Interface Science Co., Ltd.

<<Judgment criteria>>
AAA: Contact angle of 90 degrees or more AA: Contact angle of 85 degrees or more but less than 90 degrees A: Contact angle of 80 degrees or more but less than 85 degrees B: Contact angle of 65 degrees or more but less than 80 degrees C: Contact angle of 50 degrees or more but less than 65 degrees D: Contact angle less than 50 degrees If the water stain evaluation standard is B or more, it can be used for practical purposes, but if the evaluation result is A, the effect of suppressing water stains is high, and if it is AA or AAA, the effect of suppressing water stains is extremely high.

The coloring materials in Table 1 are as follows. The same applies to Tables 2 and 3.
"R-1" (organic pigment): C.I. R177, manufactured by BASF Corporation, Chromophthal Red A3B.
"R-2" (organic pigment): C.I. R177, Chromophthal Red A2B, manufactured by BASF Corporation.
"R-3" (organic pigment): C.I. R177, manufactured by BASF Corporation, Irgazin Red A2BN.
"R-4" (organic pigment): C.I. R177, manufactured by Yuri Kako Co., Ltd., FAST RED A3B.
"Y-1" (organic pigment): C.I.Y138, manufactured by BASF Corporation, Paliotol Yellow K0961HD.
"G-1" (organic pigment): C.I. G58, manufactured by DIC Corporation, FASTOGEN Green A110.
"V-1" (dye): C.I. Acid Red 289, manufactured by Tokyo Chemical Industry Co., Ltd., AR289.
"Y-2" (dye): C.I. Solvent Yellow 162, manufactured by BASF Corporation, NEPTUN YELLOW 075.

The sodium (Na) and potassium (K) contents are not shown in Table 1, but were almost the same in all examples.
Although not shown in Table 1, in Colorant Dispersion Liquid Preparation Examples 1 to 9, the initial viscosity of the colorant dispersion liquid was low at 20 mPa·s or less, which was within the practical range.
The viscosity was measured using a vibration viscometer (VM-200T2 manufactured by Sekonic) at 25.0±1.0° C. If the viscosity of the colorant dispersion liquid is 20 mPa·s or less, it is within the practical range.

In Table 3, the photopolymerization initiators are as follows.
"NCI-831": Oxime ester photopolymerization initiator (manufactured by ADEKA Corporation)
"Irg369": α-aminoketone photopolymerization initiator (Irgacure 369, manufactured by BASF)
"Irg907": α-aminoketone photopolymerization initiator (Irgacure 907, manufactured by BASF)

<Results regarding colorant dispersion liquid>
As can be seen from Table 1, in all of the colorant dispersion liquid preparation examples in which the total mass of calcium (Ca) and iron (Fe) contained in the colorant dispersion liquid for color filters was 180 mass ppm or less with respect to the entire colorant dispersion liquid for color filters, the dispersion stability was rated as "AA,""A," or "B," which was at a practical level.
On the other hand, in all of the colorant dispersion liquid preparation examples in which the total mass of calcium (Ca) and iron (Fe) was more than 180 mass ppm relative to the entire colorant dispersion liquid for color filters, the dispersion stability was rated as "C" or "D," and did not reach a practical level.
It was also found that the above results hold true regardless of the type of colorant. It was also found that dispersion stability was high even when the total concentration of calcium (Ca) and iron (Fe) was lowered by washing (Colorant Dispersion Liquid Preparation Examples 1 to 4 and 9), and even when the total concentration was low from the beginning (Colorant Dispersion Liquid Preparation Examples 5 to 8). It was also found that the above tendency holds true regardless of the type of colorant.

Furthermore, "Organic Pigment (R-1) of Colorant Dispersion Liquid Preparation Example 101," which had a total concentration of calcium (Ca) and iron (Fe) of more than 180 ppm by mass relative to the total colorant dispersion liquid for color filters before washing and thus had a dispersion stability rating of "C," was washed with water. In Colorant Dispersion Liquid Preparation Examples 1 to 4 and 9, the total concentration of calcium (Ca) and iron (Fe) in the colorant dispersion liquid was reduced to 180 ppm by mass or less, and the dispersibility was rated as "A" or "AA."

Increasing the number of washings (water washings) improved the dispersion stability (Colorant Dispersion Liquid Preparation Examples 1 to 3), and washing (water washing) by a continuous method provided excellent dispersion stability (Colorant Dispersion Liquid Preparation Example 4).
Furthermore, when comparing Colorant Dispersion Liquid Preparation Example 3 and Colorant Dispersion Liquid Preparation Example 9, in which the colorant (organic pigment) and purification method were unified and only the dispersant was changed, both were rated as "AA", but Colorant Dispersion Liquid Preparation Example 9, in which Dispersant B was used, had better dispersion stability than Colorant Dispersion Liquid Preparation Example 3, in which Dispersant A was used.

<Results regarding coloring compositions for color filters>
Furthermore, as can be seen from Table 2, in all of the colored composition preparation examples in which the total mass of calcium (Ca) and iron (Fe) contained in the colored composition for color filter was 120 mass ppm or less relative to the entire colored composition for color filter, the development speed was rated as "AA,""A," or "B," which was excellent or at a practical level. Furthermore, all of the colored compositions had excellent stability.
On the other hand, in all of the coloring composition preparation examples in which the total mass of calcium (Ca) and iron (Fe) was more than 120 mass ppm relative to the entire coloring composition for color filter, the development speed was rated as "C" or "D," and did not reach a practical level. Furthermore, it was found that the above tendency can be said regardless of the type of colorant.

In addition, when comparing Coloring Composition Preparation Example 13 and Coloring Composition Preparation Example 19, in which the colorant (organic pigment) and purification method were the same and only the dispersant was changed, Coloring Composition Preparation Example 19, which used Dispersant B, had a better development speed than Coloring Composition Preparation Example 13, which used Dispersant A, and was rated "AA."

As can be seen from Table 3, when a coloring composition containing an alkali-soluble resin having a hydrocarbon ring was used after reducing the specific metal element (Coloring Composition Preparation Examples 21 to 34), the development residue could be reduced and the occurrence of water stains tended to be suppressed. In particular, in the case of a coloring composition containing an alkali-soluble resin having a maleimide structure represented by the general formula (6) (Coloring Composition Preparation Examples 25 to 28, 30), the development residue could be extremely reduced.
Furthermore, when the coloring composition contained a mercapto compound (Coloring Composition Preparation Examples 21 to 28), the occurrence of water stains was suppressed compared to when the coloring composition did not contain a mercapto compound (Coloring Composition Preparation Example 29).
In Colored Composition Preparation Example 122 containing a large amount of the first specific metal elements (Ca and Fe), drying unevenness occurred, the development speed was slow, and there was a large amount of development residue.

The coloring composition of the present invention, which has a specified metal content, has a high colorant concentration and low viscosity, making it possible to reduce the film thickness of color filters, and is therefore widely used in the manufacture of various displays, etc.

Claims (18)

A coloring composition containing a colorant, a solvent, a polymerization initiator, and an alkali-soluble resin, wherein the total mass of calcium (Ca) and iron (Fe) contained in the coloring composition is 0.5 ppm by mass or more and 120 ppm by mass or less with respect to the entire coloring composition;
the entire amount of the coloring material is an organic pigment, and the organic pigment contains a pigment sulfonated derivative in an amount of 0.5 to 30 parts by mass per 100 parts by mass of the pigment;
the alkali-soluble resin is an acrylic copolymer having a structural unit having a carboxyl group and a structural unit having a hydrocarbon ring,
the alkali-soluble resin has a styrene structural unit as the structural unit having a hydrocarbon ring ,
50% by mass or more of the structural units having a hydrocarbon ring are styrene structural units,
A coloring composition for color filters, comprising a dispersant containing a structural unit represented by the following general formula (1):
[In general formula (1), ^R1 represents a hydrogen atom or a methyl group, A represents a divalent linking group, ^R2 and ^R3 each independently represent a hydrogen atom or a hydrocarbon group which may contain a heteroatom, and ^R2 and ^R3 may be bonded to each other to form a ring structure.] The coloring composition for color filters according to claim 1, further comprising a total mass of magnesium (Mg) and chromium (Cr) contained in the coloring composition of 135 mass ppm or less based on the total mass of the coloring composition. The coloring composition for color filters according to claim 1 or 2, further comprising a total mass of magnesium (Mg), aluminum (Al), and chromium (Cr) contained in the coloring composition of 135 mass ppm or less based on the total mass of the coloring composition. The coloring composition for color filters according to any one of claims 1 to 3, wherein the alkali-soluble resin has an acid value of 30 to 200 mg KOH/g. 5. The coloring composition for color filters according to claim 1 , wherein the alkali-soluble resin further has a maleimide structure represented by the following general formula (6) as the structural unit having a hydrocarbon ring :
[In general formula (6), R ^M represents a hydrocarbon group having an optionally substituted cyclic structure.] 6. The coloring composition for color filters according to claim 1 , wherein the alkali-soluble resin has two or more types of structural units having a hydrocarbon ring. 7. The coloring composition for color filters according to claim 1 , wherein the coloring composition contains two or more alkali-soluble resins having a hydrocarbon ring, and at least two of the alkali-soluble resins have structural units different from each other. 8. The coloring composition for color filters according to claim 1, further comprising an oxime ester-based photopolymerization initiator. 9. The coloring composition for color filters according to claim 1, further comprising one or more compounds selected from the group consisting of α-aminoketone-based photopolymerization initiators, biimidazole-based photopolymerization initiators, thioxanthone -based photopolymerization initiators, and acylphosphine oxide-based photopolymerization initiators. The coloring composition for color filters according to any one of claims 1 to 9 , which contains a mercapto compound. 11. The coloring composition for color filter according to any one of claims 1 to 10, wherein at least a portion of the structural units represented by general formula (1) in the dispersant are structural units formed by bonding to one or more compounds selected from the group consisting of compounds represented by the following general formulas (2) to ( 4 ) to form a salt such that nitrogen in the structural unit becomes an ammonium ion:
[In general formula (2), R ^a represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, a phenyl group, or a benzyl group which may have a substituent; or -O-R ^e , where R ^e represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, a phenyl group, or a benzyl group which may have a substituent; or a (meth)acryloyl group connected via an alkylene group having 1 to 4 carbon atoms.]
[In general formula (3), R ^b , R ^b′ and R ^b″ each independently represent a hydrogen atom; an acidic group or an ester group thereof; a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may have a substituent; a vinyl group, a phenyl group or a benzyl group which may have a substituent; or —O—R ^f , where R ^f represents a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms which may have a substituent; a vinyl group, a phenyl group or a benzyl group which may have a substituent; or a (meth)acryloyl group connected via an alkylene group having 1 to 4 carbon atoms; and X represents a chlorine atom, a bromine atom or an iodine atom.]
[In general formula (4), R ^c and R ^d each independently represent a hydrogen atom; a hydroxyl group; a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, a phenyl group, or a benzyl group which may have a substituent; or -O-R ^g , where R ^g represents a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms; a vinyl group, a phenyl group, or a benzyl group which may have a substituent; or a (meth)acryloyl group connected via an alkylene group having 1 to 4 carbon atoms, with the proviso that at least one of R ^c and R ^d contains a carbon atom.] 12. The coloring composition for color filters according to claim 1 , wherein the coloring material is one or more organic pigments selected from the group consisting of anthraquinone pigments, diketopyrrolopyrrole pigments, azo pigments, quinophthalone pigments, dioxazine pigments, and phthalocyanine pigments. 13. The coloring composition for color filter according to claim 1, wherein the solvent contains a glycol ether acetate solvent having a boiling point of less than 150°C as a first solvent and a solvent having a boiling point of 172°C or higher and 200°C or lower as a second solvent, and the content of the solvent having a boiling point of 172°C or higher and 200°C or lower is 1% by mass or higher and 30% by mass or lower based on the total solvent. The coloring composition for color filters according to claim 13 , wherein the solvent having a boiling point of 172°C or higher and 200°C or lower is at least one selected from the group consisting of diethylene glycol ethyl methyl ether, 3-methoxy-3-methyl-1-butyl acetate, and 3-methoxybutyl acetate. 15. The coloring composition for color filters according to any one of claims 1 to 14, wherein the alkali-soluble resin is an acrylic copolymer having a structural unit having a carboxyl group and a structural unit having a hydrocarbon ring, the acrylic copolymer contains at least 50% by mass of the structural unit having the hydrocarbon ring, and 50% by mass or more of the structural unit having the hydrocarbon ring is a styrene structural unit. 15. The coloring composition for color filters according to claim 1, wherein the alkali-soluble resin is any one of the following (i) to (iii):
i) a resin in which a side chain having an ethylenic double bond has been introduced into the main chain of a polymer formed by copolymerization of 40 parts by mass of styrene, 15 parts by mass of methyl methacrylate, and 25 parts by mass of methacrylic acid using 20 parts by mass of glycidyl methacrylate; ii) a resin in which a side chain having an ethylenic double bond has been introduced into the main chain of a polymer formed by copolymerization of 20 parts by mass of styrene, 20 parts by mass of N-phenylmaleimide, 15 parts by mass of methyl methacrylate, and 25 parts by mass of methacrylic acid using 20 parts by mass of glycidyl methacrylate; A resin obtained by mixing, in a mass ratio of 50:50, a resin in which a side chain having an ethylenic double bond has been introduced, using 20 parts by mass of glycidyl methacrylate, into the main chain of a polymer formed by copolymerizing 40 parts by mass of ethylene, 15 parts by mass of methyl methacrylate, and 25 parts by mass of methacrylic acid, and a resin in which a side chain having an ethylenic double bond has been introduced, using 20 parts by mass of glycidyl methacrylate, into the main chain of a polymer formed by copolymerizing 40 parts by mass of N-phenylmaleimide, 15 parts by mass of methyl methacrylate, and 25 parts by mass of methacrylic acid. A color filter comprising a colored layer which is a cured product of the colored composition for color filters according to any one of claims 1 to 16 . A display device comprising the color filter according to claim 17 .