Pigment composition, coloring composition for color filter, and color filter

Abstract

The present invention addresses the problem of providing: a pigment composition which can particularly enlarge a blue-partial region in a red pixel section; a coloring composition for a color filter, which contains the pigment composition; and a color filter. Specifically, the pigment composition according to the present invention comprises: at least one dye selected from the group consisting of solvent red 122, solvent red 52, solvent orange 99, solvent red 135, solvent red 225, solvent orange 116, solvent red 146, and solvent red 119; and C.I. Pigment red 177. A coloring composition for a color filter according to the present invention contains the pigment composition, a solvent, and a binder resin. The color filter of the present invention has a pixel portion containing a pigment composition.

Description

Technical Field

[0001] The present invention relates to a pigment composition, a coloring composition for a color filter containing the pigment composition, and a color filter having a pixel portion containing the pigment composition. Background Art

[0002] Color filters convert white backlight light into red, green, and blue, thereby achieving color reproduction on displays. High-color reproduction display standards require high color reproduction from red colorants used in color filters. Achieving high color reproduction requires expanding the displayable color gamut. It has been shown that increasing the chromaticity x in red pixels, i.e., using a bluish red colorant, can expand the color gamut.

[0003] In recent years, CI Pigment Red 269 has been developed as a bluish, high-brightness red colorant. However, CI Pigment Red 269 has disadvantages such as low contrast and low heat resistance, and thus has not yet been used in practical color filters.

[0004] On the other hand, CI Pigment Red 177, used as a bluish red colorant in conventional color filter products, has excellent contrast and heat resistance, but is not bluish enough and lacks high color reproduction.

[0005] As a coloring composition for a color filter used in the red pixel portion as described above, there is, for example, Patent Document 1 below. Patent Document 1 discloses a coloring composition for a color filter comprising a colorant, a metal complex, a binder resin, and an organic solvent, wherein the colorant comprises a specific naphthol azo pigment and a metal complex having a specific central metal.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 2016-114940 Summary of the Invention

[0009] Problems to be solved by the invention

[0010] Although Patent Document 1 uses a metal complex dye to improve contrast, it fails to achieve a color gamut expansion effect. To expand the color gamut of a red colorant toward the bluish side, it is considered necessary to modify the pigment's skeleton, such as replacing CI Pigment Red 177 with Pigment Red 269. In other prior art applications other than Patent Document 1, CI Pigment Red 177 is used as a bluish red colorant for color filters. However, due to its insufficient bluish color, it is unable to display a color gamut with high color reproduction.

[0011] Therefore, an object of the present invention is to provide a pigment composition that can expand a particularly bluish color range when CI Pigment Red 177, which is excellent in contrast and heat resistance, is included in a red pixel portion, a coloring composition for a color filter containing the same, and a color filter.

[0012] Means for solving problems

[0013] The present inventors have discovered that by combining CI Pigment Red 177 with a specific dye, the bluish gamut can be particularly expanded in red pixel areas. The bluish gamut described herein refers to the gamut where, in a color filter produced by mixing a pigment composition comprising Pigment Red 177 and a dye, and Pigment Yellow 139 at a specific ratio, the value of x exceeds 0.6861 when the chromaticity coordinates, represented by chromaticity x and y, measured under illuminant C, are y = 0.312.

[0014] In the present invention, the mechanism for expanding the bluish color range is presumed to be as follows: By adding a specific dye, the insufficient long-wavelength absorption of Pigment Red 177 can be supplemented. This is believed to expand the bluish color range.

[0015] That is, the present invention is as follows.

[0016] [1] A pigment composition comprising at least one dye selected from the group consisting of Solvent Red 122, Solvent Red 52, Solvent Orange 99, Solvent Red 135, Solvent Red 225, Solvent Orange 116, Solvent Red 146, and Solvent Red 119, and CI Pigment Red 177.

[0017] [2] A coloring composition for a color filter, comprising the pigment composition described in [1], a solvent, and a binder resin.

[0018] [3] A color filter having a pixel portion containing the pigment composition described in [1].

[0019] Effects of the Invention

[0020] The pigment composition of the present invention can particularly expand the bluish region in the red pixel portion, thereby expanding the region displayable with chromaticity x and y. Therefore, it is suitable as a coloring composition for color filters for producing red pixel portions in color filters. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a graph in which the chromaticity x and y values ​​measured using light source C in the characteristic evaluation of the color filter of the example are plotted. DETAILED DESCRIPTION

[0022] [Pigment composition]

[0023] The pigment composition of the present invention comprises at least one dye selected from the group consisting of Solvent Red 122 (SR122), Solvent Red 52 (SR52), Solvent Orange 99 (SO99), Solvent Red 135 (SR135), Solvent Red 225 (SR225), Solvent Orange 116 (SO116), Solvent Red 146 (SR146), and Solvent Red 119 (SR119), and CI Pigment Red 177 (PR177), an anthraquinone pigment. The pigment composition of the present invention is not particularly limited as long as it comprises the above-mentioned dyes and PR177, and may also comprise other dyes or pigments. The above-mentioned dyes may be used alone or in combination of two or more.

[0024] The PR177 used in the present invention is preferably micronized before use, but the micronization method is not particularly limited. For example, any of wet grinding, dry grinding, and dissolution separation methods can be used. From the perspective of good dispersion in the colorant carrier, the primary particle size of the micronized pigment is preferably 20 nm or more. In addition, from the perspective of being able to form a high-contrast color filter, it is preferably 100 nm or less. The particularly preferred range is 25 to 85 nm. When micronizing PR177, a resin can be added as needed. Examples of the resin include natural resins, modified natural resins, synthetic resins, and synthetic resins modified from natural resins.

[0025] Among the dyes of the present invention, Solvent Red 122, Solvent Red 52, Solvent Orange 99, Solvent Red 135, Solvent Red 225, and Solvent Orange 116 are preferred, and Solvent Red 122 is particularly preferred because they have a greater effect of expanding the bluish color range.

[0026] The dye of the present invention is preferably soluble at room temperature in an organic solvent commonly used in color filter production, such as propylene glycol monomethyl ether acetate. Furthermore, it is more preferably a dye that dissolves in the colorant carrier when the color filter coating is heated at 230°C for one hour. Using such a dye with good solubility can produce a color filter coloring composition with excellent brightness and contrast.

[0027] When the color range near the DCI standard is preferably used, the ratio of the above-mentioned dye (including two or more kinds of the total) in the pigment composition of the present invention is preferably 0.5 to 8% by mass, 2 to 8 parts by mass. When the color range is preferably more bluish, the ratio of the above-mentioned dye is, for example, more preferably 30 to 40% by mass. When the color range is preferably more bluish (BT2020 standard, etc.), the ratio of the above-mentioned dye is, for example, more preferably 80 to 90% by mass.

[0028] The pigment composition of the present invention may also contain red organic pigments other than PR177, blue organic pigments, and yellow organic pigments. Examples of red organic pigments other than PR177 include CI 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, 166, 168, 169, 170, 172, 173, 174, 175, 176, 178, 179, 181, 184, 185, 187, 188, 190, 193, 194, 200, 202, 206, 207, 208, 209, 210, 214, 216, 220, 221, 224, 230, 231, 2 32, 233, 235, 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.

[0029] Examples of the blue organic pigment include CI Pigment Blue 1, 1:2, 9, 14, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17, 19, 25, 26, 27, 28, 29, 33, 35, 36, 56, 56:1, 60, 61, 61:1, 62, 63, 64, 66, 67, 68, 71, 72, 73, 74, 75, 76, 78, 79, and 80.

[0030] Examples of yellow organic pigments include CI 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 4, 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, 229.

[0031] Red organic pigments, blue organic pigments, and yellow organic pigments other than PR177 can be used in a range not impairing the effects of the present invention, but their proportion in the pigments in the pigment composition of the present invention is, for example, 20% by mass or less, preferably 10% by mass or less.

[0032] Dyes other than the dye of the present invention described above may also be used. Examples of such dyes include red dyes such as Solvent Red 109, Solvent Red 111, Solvent Red 124, Solvent Red 149, Solvent Red 150, Solvent Red 168, Solvent Red 169, Solvent Red 172, Solvent Red 179, Solvent Red 195, Solvent Red 196, Solvent Red 197, Solvent Red 207, Solvent Red 222, Solvent Red 227, Solvent Red 23, Solvent Red 24, Solvent Red 25, Solvent Red 27, Solvent Red 3, Solvent Red 312, Solvent Red 313, Solvent Red 49, and Solvent Red 8. Examples of orange dyes include Solvent Orange 107, Solvent Orange 14, Solvent Orange 3, Solvent Orange 54, Solvent Orange 60, Solvent Orange 62, Solvent Orange 63, and Solvent Orange 86. Examples of yellow dyes include Solvent Yellow 114, Solvent Yellow 131, Solvent Yellow 135, Solvent Yellow 14, Solvent Yellow 157, Solvent Yellow 16, Solvent Yellow 160, Solvent Yellow 163, Solvent Yellow 167, Solvent Yellow 176, Solvent Yellow 179, Solvent Yellow 185, Solvent Yellow 189, Solvent Yellow 2, Solvent Yellow 21, Solvent Yellow 33, Solvent Yellow 43, Solvent Yellow 44, Solvent Yellow 56, Solvent Yellow 65, Solvent Yellow 82, Solvent Yellow 85, Solvent Yellow 93, and Solvent Yellow 98. Examples of green dyes include Solvent Green 28, Solvent Green 3, Solvent Green 5, and Solvent Green 7.

[0033] Dyes other than those described above may be used within a range that does not impair the effects of the present invention, but their proportion in the dyes in the pigment composition of the present invention is, for example, 20% by mass or less, preferably 10% by mass or less.

[0034] The primary particle size of the pigment in the pigment composition of the present invention is, for example, 20 to 150 nm, preferably 20 to 100 nm. If the primary particle size of the pigment exceeds 150 nm, dispersion stability may deteriorate, resulting in a tendency to cause light scattering. The pigment composition of the present invention may also be subjected to a micronization treatment. Micronization is typically performed by a pulverization method such as dry pulverization or wet pulverization.

[0035] The primary particle size of the pigment in the pigment composition of the present invention is determined by dispersing the pigment composition in a solvent such as cyclohexanone, applying the dispersion onto a colloidal film, and capturing a scanning electron microscope (TEM) image. The sizes of 1000 particles in the resulting image are measured, and the average value is defined as the primary particle size of the pigment.

[0036] In the pigment composition of the present invention, in addition to the pigment / dyes, various derivatives may be used in combination as needed to improve dispersibility. Examples of substituents on the pigment / dye backbone in such derivatives include sulfonic acid groups, sulfonamide groups and their quaternary salts, phthalimidomethyl groups, dialkylaminoalkyl groups, hydroxyl groups, carboxyl groups, and amide groups, which are directly bonded to the pigment backbone or bonded to the pigment backbone via alkyl groups, aryl groups, heterocyclic groups, and the like.

[0037] The pigment composition of the present invention can be prepared by mixing and stirring (dry blending) a pigment including PR177 and a powder of a dye such as Solvent Red 122, or by mixing the pigment and the dye in separate dispersions.

[0038] [Coloring composition for color filter]

[0039] The coloring composition for color filters of the present invention contains the pigment composition of the present invention, a solvent, and a binder resin. In addition to the above, the coloring composition may also contain a resin-based dispersant or the like as needed.

[0040] As the above-mentioned solvent, an organic solvent is generally used. Examples of such organic solvents include diisopropyl ether, mineral spirits, n-pentane, amyl ether, ethyl caprylate, n-hexane, diethyl ether, isoprene, ethyl isobutyl ether, butyl stearate, n-octane, Varsol #2, Apco #18 solvent, diisobutylene, amyl acetate, butyl acetate, Apco thinner, butyl ether, diisobutyl ketone, methylcyclohexene, methyl nonyl ketone, dipropyl ether, dodecane, SoCalSolvent No. 1 and No. 2, amyl formate, dihexyl ether, diisopropyl ketone, SOLVESSO #150, (n-, iso-, tert-)butyl acetate, hexene, Shell TS28 solvent, chlorobutane, ethyl amyl ketone, ethyl benzoate, chloropentane, ethylene glycol diethyl ether, ethyl orthoformate, and the like. orthoformate), methoxymethyl amyl ketone, methyl butyl ketone, methyl hexyl ketone, methyl isobutyrate, benzonitrile, ethyl propionate, methyl cellosolve acetate, methyl isoamyl ketone, n-amyl methyl ketone (2-heptanone), methyl isobutyl ketone, propyl acetate, amyl acetate, amyl formate, dicyclohexyl, diethylene glycol monoethyl ether acetate, dipentene, methoxymethyl amyl alcohol, methyl amyl ketone, methyl isopropyl ketone, propyl propionate, propylene glycol tert-butyl ether, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, ethyl cellosolve acetate, carbitol, cyclohexanone, ethyl acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl 3-methoxypropionic acid, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, ethylene glycol acetate, ethyl carbitol, butyl carbitol, ethylene glycol monobutyl ether, propylene glycol tert-butyl ether, 3-methoxybutanol, 3-methyl-3-methoxybutanol, tripropylene glycol methyl ether, ethyl lactate.

[0041] To prepare the coloring composition of the present invention, these solvents may be used alone or in combination of two or more. In the coloring composition, the solvent is usually used in an amount of 500 to 900 parts by mass, preferably 600 to 800 parts by mass, per 100 parts by mass of the pigment composition.

[0042] Examples of the binder resin include thermoplastic resins and thermosetting resins. The resin is preferably a transparent resin having a spectral transmittance of preferably 80% or more, more preferably 95% or more, in the entire wavelength range of 400 to 700 nm in the visible light region.

[0043] Examples of the thermoplastic resin include acrylic resins, butyral resins, styrene-maleic acid copolymers, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymers, polyvinyl acetate, polyurethane resins, polyester resins, vinyl resins, alkyd resins, polystyrene resins, polyamide resins, rubber resins, cyclized rubber resins, cellulose resins, polyethylene (HDPE, LDPE), polybutadiene, and polyimide resins. Examples of the thermosetting resin include epoxy resins, benzoguanamine resins, rosin-modified maleic acid resins, rosin-modified fumaric acid resins, melamine resins, urea resins, and phenolic resins.

[0044] The ratio of the binder resin relative to 100 parts by mass of the pigment composition is, for example, 30 to 500 parts by mass, or preferably 40 to 400 parts by mass.

[0045] When dispersing the above-mentioned pigment composition in a solvent, a resin-based dispersant may also be used to improve dispersibility and dispersion stability. This resin-based dispersant is a substance that has the function of combining with the organic pigment and anchoring site, extending the compatibility portion in the dispersion medium to form a dispersion. It is a different type from the alkali-soluble resin and photopolymerizable monomer used to prepare the photosensitive composition described below. In addition to the resin-based dispersant, rosin, surfactant, etc. may also be included. These components may be treated on the pigment surface (so-called surface treatment) or not. As methods for treating the pigment surface, known methods such as rosin treatment, surfactant treatment, solvent treatment, and resin treatment may be used.

[0046] Examples of the resin-based dispersant include those having a polymer chain, such as polyurethane resin, polyethyleneimine, polyoxyethylene glycol diester, acrylic resin, polyester resin, etc. Among them, polyester resin-based dispersants and / or acrylic resin-based dispersants are preferred in terms of dispersibility, heat resistance, and light resistance.

[0047] Specific examples of various resin-based dispersants include those with trade names such as AJISPER (manufactured by Ajinomoto Fine-Techno Co., Ltd.), EFKA (manufactured by BASF), DISPERBYK (manufactured by BYK Chemie Co., Ltd.), BYKLPN (manufactured by BYK Chemie Co., Ltd.), DISPARLON (manufactured by Kusumoto Chemicals Co., Ltd.), SOLSPERSE (manufactured by Lubrizol), KP (manufactured by Shin-Etsu Chemical Co., Ltd.), and POLYFLOW (manufactured by Kyoeisha Chemical Co., Ltd.). These dispersants may be used alone or in combination of two or more in any combination and ratio.

[0048] The ratio of the resin-based dispersant is, for example, 30 to 60 parts by mass, or preferably 38 to 50 parts by mass per 100 parts by mass of the pigment composition.

[0049] The above-mentioned coloring composition can be prepared by stirring and mixing the pigment composition of the present invention, a solvent and a resin-based dispersant added as needed. If necessary, it can also be prepared by vibrating for a necessary time in the presence of various pulverizing media such as beads and rods, and dispersing the medium by filtration. The coloring composition of the present invention is used for the red pixel portion of the color filter. In order to form a red pixel (toning) of a preferred hue, a coloring composition containing a yellow pigment such as Pigment Yellow 139 is preferably mixed with the coloring composition of the present invention.

[0050] In order to form a red pixel portion using the coloring composition by photolithography or the like, a photosensitive composition is usually prepared. The photosensitive composition includes, for example, the coloring composition, an alkali-soluble resin, a photopolymerizable monomer, and a photopolymerization initiator.

[0051] Examples of the alkali-soluble resin include resins containing a carboxyl group or an acidic hydroxyl group, such as novolac-type phenolic resins, alkyl (meth)acrylate (meth)acrylic acid copolymers, styrene (meth)acrylic acid copolymers, and styrene-maleic acid copolymers.

[0052] Examples of the photopolymerizable monomer include bifunctional monomers such as 1,6-hexanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, bis[(meth)acryloyloxyethoxy]bisphenol A, and 3-methylpentanediol di(meth)acrylate; polyfunctional monomers having a relatively small molecular weight such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, and ditrimethylolpropane tetra(meth)acrylate; and various polyfunctional monomers having a relatively large molecular weight such as polyester acrylate, polyurethane acrylate, and polyether acrylate.

[0053] Examples of the photopolymerization initiator include acetophenone, benzophenone, benzyldimethylketal, benzoyl peroxide, 2-chlorothioxanthone, 1,3-bis(4'-azidobenzylidene)-2-propane, 1,3-bis(4-azidobenzylidene)-2-propane-2'-sulfonic acid, 4,4'-diazidebenzylene-2,2'-disulfonic acid, ethanone, and 1-[9-ethyl-6-[2-methyl-4-(2,2-dimethyl-1,3-dioxolanyl)methoxybenzoyl]-9.H.-carbazol-3-yl]-1-(O-acetoxime).

[0054] The photosensitive composition is prepared by adding 3 to 20 parts in total of an alkali-soluble resin and a photopolymerizable monomer to 1 part of the pigment composition of the present invention, adding 0.05 to 3 parts of a photopolymerization initiator to 1 part of the photopolymerizable monomer, and optionally further adding a solvent for preparing the coloring composition, and stirring and dispersing the mixture uniformly to obtain a photosensitive composition for forming a pixel portion.

[0055] [Color Filter]

[0056] The color filter of the present invention has a pixel portion containing the pigment composition of the present invention. The color filter of the present invention can be produced by a known and conventional method using a photosensitive composition containing the coloring composition of the present invention.

[0057] The representative manufacturing method of the color filter is photolithography, which is the following method, that is, for the red pixel portion, the above-mentioned photosensitive composition comprising the coloring composition of the present invention is applied on a transparent substrate such as glass for the color filter, and after heating and drying (pre-baking), ultraviolet rays are irradiated through a mask, thereby performing pattern exposure, and after the photocurable compound corresponding to the pixel portion of the red pixel portion is cured, the unexposed portion is developed with a developer, the non-pixel portion is removed, and the pixel portion is fixedly attached to the transparent substrate. By this method, the red pixel portion formed by the cured coloring film of the photosensitive composition can be formed on a transparent substrate. Each pixel portion of green (G) and blue (B) can also be made in the same manner as described above from a photosensitive composition prepared from an organic pigment of each color.

[0058] As a method for coating a photosensitive composition on a transparent substrate, there are spin coating, roll coating, slit coating, ink jet method, etc. in addition to the photolithography method.

[0059] The drying conditions of the coating film of the photosensitive composition applied to the transparent substrate vary depending on the type and proportion of each component, but are generally 50 to 150°C for about 1 to 15 minutes. This heating treatment is generally called pre-baking. In addition, as the light used for photocuring of the photosensitive composition, ultraviolet rays or visible light in the wavelength range of 200 to 500 nm are preferably used. Various light sources that emit light in this wavelength range can be used. As development methods that can use various light sources that emit light in this wavelength range, for example, a liquid method, an immersion method, a spraying method, etc. can be mentioned. After exposure and development of the photosensitive composition, the transparent substrate with the pixel portion of the desired color formed is washed with water and then dried. The color filter obtained in this manner is passed through a heating device such as a hot plate or an oven and subjected to a predetermined time heating treatment (post-baking) at 90 to 280°C to remove the volatile components in the colored coating film. At the same time, the unreacted photocurable compound remaining in the cured colored film of the photosensitive composition is thermally cured to complete the color filter.

[0060] The color filter can be obtained as follows: by forming a coating film of a pixel portion by the above-mentioned method, sealing a liquid crystal material between a pair of parallel transparent electrodes, dividing the transparent electrodes into discontinuous fine intervals, and at the same time, alternately arranging color filter colored pixel portions of any one color selected from red (R), green (G) and blue (B) in a pattern in each fine interval divided into a grid shape by a black matrix on the transparent electrode, or by forming a color filter colored pixel portion on a substrate and then arranging a transparent electrode.

[0061] Example

[0062] Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. In the present Examples, "parts" means "parts by mass."

[0063] [Preparation of Pigment Composition]

[0064] Pigment Red 177 and the dyes or pigments listed in Table 1 below were mixed and stirred at the ratios listed in Table 1 to obtain pigment compositions 1 to 17. In addition, in pigment composition 17, Pigment Red 269 was used instead of Pigment Red 177.

[0065] [Table 1]

[0066]

[0067] [Preparation of Coloring Composition for Color Filter Property Evaluation]

[0068] 1.82 parts of a mixture prepared by mixing the pigment composition prepared in Table 1 above with Pigment Yellow 139 at a mixing ratio of pigment composition to Pigment Yellow 139 of 9:1 to 1:9, 3.63 parts of BYK LPN-21116 (manufactured by BYK Chemie Co., Ltd.), and 12.75 parts of propylene glycol monomethyl ether acetate were mixed. Zirconia beads having a diameter of 0.3 to 0.4 mm were added, and the mixture was dispersed for 3 hours using a paint conditioner (manufactured by Toyo Seiki Co., Ltd.) to obtain the coloring compositions of Examples 1-1 to 1-13 and Comparative Examples 1-1 to 1-2.

[0069] [Production of Evaluation Color Filters]

[0070] The coloring composition was applied to a soda glass substrate using a spin coater, dried at 90°C for 3 minutes, and then heated (post-baked) at 230°C for 1 hour. The spin coater speed was adjusted to obtain a coating film with a thickness of approximately 3.5 μm after drying. The film thickness was measured using a white light interference microscope (VS1330) manufactured by Hitachi High-Tech Scientific Co., Ltd. In this manner, multiple evaluation color filters were prepared with different composition ratios of the pigment composition to Pigment Yellow 139.

[0071] [Characteristics Evaluation of Color Filter: Chromaticity x of Specific Chromaticity y]

[0072] Figure 1 This is a graph obtained by plotting the chromaticity x and y values ​​obtained by measuring the color of the color filter produced above using a spectrophotometer (U3900 manufactured by Hitachi High-Tech Scientific Co., Ltd.) using a C light source. Figure 1In the table, the data of Examples 1-1 to 1-13 and Comparative Example 1-1 are shown. In addition, the following Table 2 is a table for calculating the value of x that becomes chromaticity y = 0.312 for Examples 1-1 to 1-13 and Comparative Examples 1-1 to 1-2. By comparing the value of chromaticity x of a specific chromaticity y, the width of the color gamut relative to Pigment Red 177 is evaluated by the chromaticity difference Δx. If Δx (PR177 ratio) is a positive value, it means that the chromaticity is in the blue direction, that is, the color gamut is expanded. It should be noted that, regarding Comparative Example 1-2, since the chromaticity y = 0.312 could not be achieved, it was not evaluated.

[0073] [Table 2]

[0074] Pigment composition The value of x where y = 0.312 Δx (PR177 ratio) Example 1-1 Pigment composition 1 0.68700 0.00090 Example 1-2 Pigment composition 2 0.68639 0.00029 Examples 1-3 Pigment composition 3 0.68636 0.00026 Examples 1-4 Pigment composition 4 0.68632 0.00022 Examples 1-5 Pigment composition 5 0.68628 0.00018 Examples 1-6 Pigment composition 6 0.68622 0.00012 Examples 1-7 Pigment composition 7 0.68620 0.00010 Examples 1-8 Pigment composition 8 0.68618 0.00008 Examples 1-9 Pigment composition 9 0.68757 0.00147 Examples 1-10 Pigment composition 10 0.68760 0.00150 Examples 1-11 Pigment composition 11 0.68780 0.00170 Examples 1-12 Pigment composition 12 0.68780 0.00170 Example 1-'13 Pigment composition 13 0.68780 0.00170 Comparative Example 1-1 Pigment composition 14 0.68610 0 Comparative Example 1-2 Pigment composition 15 Did not reach y = 0.312 -

[0075] According to Table 2 above, in the pigment compositions of Examples 1-1 to 1-13 containing PR177 and any of the dyes SR122, SR52, SO99, SR135, SR225, SO116, SR146, and SR119, Δx (PR177 ratio) is positive. In particular, a significant color gamut expansion effect is observed in the combination of PR177 and Solvent Red 122. Therefore, the pigment composition of the present invention can particularly expand the bluish gamut in red pixels. On the other hand, even with the same bluish colorant, adding a blue pigment such as Pigment Blue 15:6 (PB15:6) in Comparative Example 1-2 fails to achieve the desired chromaticity.

[0076] (Preparation of Coloring Composition for Heat Resistance Evaluation)

[0077] 1.82 parts of the pigment composition prepared using the pigment ratios listed in Table 1 above, 3.63 parts of BYK LPN-21116 (manufactured by BYK Chemie Co., Ltd.), and 12.75 parts of propylene glycol monomethyl ether acetate were mixed, 0.3 to 0.4 mm φ zirconium oxide beads were added, and the mixture was dispersed for 3 hours using a paint conditioner (manufactured by Toyo Seiki Co., Ltd.) to obtain the colored compositions of Examples 2-1 to 2-11 and Comparative Examples 2-1 to 2-2.

[0078] (Evaluation of Heat Resistance of Pigment Composition)

[0079] The coloring composition was applied to a soda glass substrate using a spin coater to a dry film thickness of 3.5 μm, and then dried at 90°C for 3 minutes and allowed to cool to produce a coated substrate. The chromaticity ([L*(1), a*(1), b*(1)]) of the obtained coating film under illuminant C was measured using a spectrophotometer (U3900, manufactured by Hitachi High-Tech Scientific Co., Ltd.). Furthermore, the chromaticity ([L*(2), a*(2), b*(2)]) under illuminant C was measured by heating (post-baking) at 230°C for 1 hour as a heat resistance test. The color difference ΔE was calculated using the following calculation formula and evaluated according to the following four levels.

[0080] ΔE=√((L*(2)-L*(1))2+(a*(2)-a*(1))2+(b*(2)-b*(1))2)

[0081] [evaluate]

[0082] ◎: The difference in ΔE from Comparative Example 2-2 is less than 20% (extremely good)

[0083] ○: The difference in ΔE from Comparative Example 2-2 is 20% or more and less than 50% (good)

[0084] Δ: The difference in ΔE from Comparative Example 2-2 is 50% or more and less than 100% (defective)

[0085] ╳: The difference in ΔE from Comparative Example 2-2 is 100% or more (extremely poor)

[0086] [Table 3]

[0087]

[0088] A smaller ΔE ratio indicates a smaller color difference before and after the heat resistance test, indicating better heat resistance. Table 3 shows that pigment compositions containing PR177 and any of the dyes SR122, SO99, SR135, SR225, SR119, and SR146 exhibited excellent or good ΔE (ratio to PR269). In summary, the pigment compositions of the present invention maintain superior heat resistance compared to PR269, a conventionally known bluish red pigment, despite containing a dye.

Claims

1. A pigment composition comprising at least one dye selected from the group consisting of Solvent Red 122, Solvent Red 52, Solvent Orange 99, Solvent Red 135, Solvent Red 225, Solvent Orange 116, Solvent Red 146, and Solvent Red 119, and CI Pigment Red 177. 2 . A coloring composition for color filters, comprising the pigment composition according to claim 1 , a solvent, and a binder resin. 3 . A color filter comprising a pixel portion containing the pigment composition according to claim 1 .

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