UV-curable inkjet composition, cured film, color filter, solid-state image sensor, and image display device.

Abstract

This invention provides UV-curable inkjet compositions, cured films, color filters, and the like that exhibit high coloring power, excellent storage stability, good ejection and curing properties, and good solvent resistance. [Solution] The inkjet composition comprises a colorant (A), a resin (B), a polymerizable compound (C), and a polymerization initiator (D), wherein (A) comprises a green pigment and a metal azo pigment (A1) containing the two compounds shown below, and the solvent content in the composition is 5.0% or less. JPEG2026113384000020.jpg35170 JPEG2026113384000021.jpg31170

Description

[Technical Field]

[0001] The present invention relates to an ultraviolet-curable inkjet composition, a cured film, a color filter, a solid-state image sensor, and an image display device. [Background technology]

[0002] In recent years, solvent-free inkjet recording methods have attracted attention. These methods involve applying an ink that can be cured by irradiation with ultraviolet light or other radiation to a desired material in an image-like manner, and then curing the applied ink to record the image. In curable compositions used in inkjet technology, ensuring the storage stability of the colorant is crucial. Problems with storage stability can lead to various issues, such as the deposition of aggregated foreign matter on the film or a decrease in the discharge performance of the curable composition. In the field of color filters used in smartphones and tablet devices, the development of solvent-free inkjet recording methods is progressing from the perspective of improving yield and simplifying the manufacturing process. As smartphones and tablet devices become thinner and lighter, there is a demand for thinner color filters incorporated into their liquid crystal displays. Furthermore, with the increasing brightness and wide color gamut of liquid crystal displays, the color filters themselves are highly luminous, and thinning is necessary to increase the aperture ratio of the filter segments and achieve higher brightness. Patent documents 1 and 2 describe the use of metal azo pigments in UV-curable inkjet compositions. However, the inkjet compositions disclosed in these documents had room for improvement in terms of coloring power and solvent resistance. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-168067 [Patent Document 2] Japanese Patent Publication No. 2023-155256 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] In order to form a thin film while maintaining the color tone of the color filter, conventional ultraviolet curable inkjet compositions need to contain a colorant at a high concentration. However, when a large amount of colorant is used to increase the coloring power, there are problems such as a decrease in the ejection property of the inkjet composition and deterioration of the solvent resistance.

[0005] An object of the present invention is to provide an ultraviolet curable inkjet composition having high coloring power, excellent storage stability, good ejection property, curability, and solvent resistance, a cured film formed from the composition, a color filter, a solid-state imaging device, and an image display device.

Means for Solving the Problems

[0006] As a result of intensive studies, the present inventors have found that an ultraviolet curable inkjet composition having high coloring power, excellent storage stability, good ejection property, curability, and solvent resistance can be obtained by containing a green pigment and a specific metal azo pigment, and thus have reached the present invention.

[0007] That is, the present invention relates to an ultraviolet curable inkjet composition containing a colorant (A), a resin (B), a polymerizable compound (C), and a polymerization initiator (D), wherein the colorant (A) contains a green pigment and a metal azo pigment (A1) containing the compounds represented by the following (a) and (b), and the content of the solvent in the ultraviolet curable inkjet composition is 5.0% or less. (a) A compound of general formula (1) or its tautomeric form

Chemical formula

[0008] Further, the present invention relates to the ultraviolet curable inkjet composition, wherein the green pigment is at least one selected from C.I. Pigment Green 36, C.I. Pigment Green 58, and C.I. Pigment Green 59.

[0009] Further, the present invention relates to the ultraviolet curable inkjet composition, wherein the polymerizable compound (C) contains a monofunctional and / or bifunctional monomer (C1) having a viscosity of 10 mPa·s or less at 25°C, and the content of the monofunctional and bifunctional monomers (C1) is 50% by mass or more and 100% by mass or less in the polymerizable compound (C).

[0010] Further, the present invention relates to the ultraviolet curable inkjet composition, wherein the colorant (A) further contains at least one selected from a red pigment, a purple pigment, and a black pigment.

[0011] Furthermore, the present invention relates to the ultraviolet-curable inkjet composition wherein the polymerization initiator (D) comprises an acylphosphine compound and / or an oxime ester compound.

[0012] Furthermore, the present invention relates to a cured film formed by the ultraviolet-curable inkjet composition.

[0013] Furthermore, the present invention relates to a color filter having the cured film.

[0014] Furthermore, the present invention relates to a solid-state image sensor comprising the aforementioned color filter.

[0015] Furthermore, the present invention relates to an image display device comprising the aforementioned color filter. [Effects of the Invention]

[0016] The present invention provides an ultraviolet-curable inkjet composition with high coloring power, excellent storage stability, good ejectability and curability, and good solvent resistance, as well as a cured film formed from the composition, a color filter, a solid-state image sensor, and an image display device. [Modes for carrying out the invention]

[0017] The embodiments for carrying out the ultraviolet-curable inkjet composition of the present invention will be described in detail below. However, the present invention is not limited to the following embodiments and can be modified and implemented within the scope of solving the problem.

[0018] In this specification, unless otherwise specified, "(meth)acryloyl," "(meth)acrylic," "(meth)acrylic acid," "(meth)acrylate," "(meth)acryloyloxy," or "(meth)acrylamide" means "acryloyl and / or methacryloyl," "acrylic and / or methacrylic," "acrylic acid and / or methacrylic acid," "acrylate and / or methacrylate," "acryloyloxy and / or methacryloyloxy," or "acrylamide and / or methacrylamide," respectively. Also, "CI" means Color Index (CI; published by The Society of Dyers and Colourists).

[0019] <Coloring agent (A)> The ultraviolet-curable inkjet composition of the present invention comprises, as a colorant (A), a green pigment and a metal azo pigment (A1) containing the compounds represented by (a) and (b) below.

[0020] (Green pigment) As the green pigment, for example, zinc phthalocyanine pigments described in CI Pigment Green 7, 10, 36, 37, 58, 59, 62, 63, JP 2008-19383, JP 2007-320986, JP 2004-70342, International Publication No. 2015 / 118720, etc., and aluminum talocyanine pigments described in Japanese Patent No. 4893859, etc., can also be used. From the viewpoint of color tone, it is preferable to use at least one selected from CI Pigment Green 36, CI Pigment Green 58, and CI Pigment Green 59.

[0021] From the viewpoint of coloring power and solvent resistance, the content of green pigment is preferably 20.0% by mass or more and 70.0% by mass or less in the coloring agent (A).

[0022] (Metal azo pigment (A1)) The metal azo pigment (A1) contains the compounds represented by (a) and (b) below.

[0023] (a) A compound of general formula (1) or its tautomeric form [Chemical formula] General formula (1) (In general formula (1), R1 and R2 each independently represent OH, NH2, or NHR5, R3 and R4 each independently represent O, or NR5, and R5 represents a hydrogen atom or an alkyl group which may have a substituent. Me represents Ni 2+ , Zn 2+ , Cu 2+ are two or more divalent metal ions selected from the group of Based on 1 mole of the total of the compounds of (a), the total amount of Ni 2+ , Zn 2+ , and Cu 2+ ions is 95 - 100 mol%.)

[0024] The alkyl group which may have a substituent in R5 may be linear, branched, cyclic, or any combination thereof, and examples include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, a hexyl group, a 2-ethylhexyl group, a cyclopentyl group, a cyclohexyl group, etc.

[0025] When the alkyl group in R5 has a substituent, examples of the substituent include a halogen atom, a hydroxy group, an alkoxy group, a cyano group, and an amino group, etc.

[0026] In general formula (1), it is preferable that R1 and R2 are each -OH.

[0027] In general formula (1), it is preferable that R3 and R4 are each O.

[0028] From the viewpoint of coloring power, Me is Ni 2+ and Zn 2+ or Cu 2+It is more preferable that Ni 2+ and Zn 2+ It is particularly preferable that this be the case.

[0029] In the compound represented by (a), the molar ratio of two or more divalent metal ions is, for example, Ni 2+ And, Zn 2+ or Cu 2+ The molar ratio is preferably 97:3 to 10:90, and more preferably 90:10 to 10:90.

[0030] At least two specific metal ions (Ni 2+ Zn 2+ Cu 2+ Embodiments including (selected from the system) include embodiments in which at least two specific metal ions are contained in a common crystal lattice and embodiments in which one type is contained in each of separate crystal lattices. Among these, the embodiment in which at least two specific metal ions are contained in a common crystal lattice is preferred. Whether the embodiment includes at least two specific metal ions in a common crystal lattice or one type is contained in each of separate crystal lattices can be determined, for example, by the X-ray diffraction method described in Japanese Patent Application Publication No. 2014-12838.

[0031] The compound represented by (a) may include compounds in which Me in general formula (1) is a metal ion other than the specified metal ion. Examples of metal ions other than the specified metal ion include Li 2+ , Cs + Mg 2+ kaNa + , K + Ca 2+ , Sr 2+ Ba + La 3+ , Pr 3+ , Nd 3+ , Cd 2+ , Zr 4+ Ce 3+ These are some examples.

[0032] (b) Compounds represented by general formula (2) [ka] General formula (2) (In general formula (2), R6 independently represents a hydrogen atom or an alkyl group which may have substituents.)

[0033] The alkyl group in R6, which may have substituents, may be linear, branched, cyclic, or a combination thereof. Examples include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, 2-ethylhexyl, cyclopentyl, and cyclohexyl groups.

[0034] If the alkyl group in R6 has substituents, examples of substituents include halogen atoms, hydroxyl groups, alkoxy groups, cyano groups, and amino groups.

[0035] In general formula (2), R6 is preferably a hydrogen atom.

[0036] The content of the compound represented by (b) is preferably 0.1 to 4 moles, and more preferably 0.5 to 3 moles, per mole of the compound represented by (a).

[0037] The metal azo pigment (A1) is preferably formed as an adduct of the compound represented by (a) and the compound represented by (b). An adduct means a molecular aggregate. The bonds between these molecules may be due to, for example, intermolecular interactions, Lewis acid-base interactions, coordination bonds, or chain bonds. The adduct may also have a structure like an inclusion compound in which the guest molecule is incorporated into the lattice constituting the host molecule. The adduct may also have a structure like a composite intercalated crystal. A composite intercalated crystal is a chemically non-stoichiometric crystalline compound consisting of at least two elements. The adduct may also be a mixed substitution crystal in which the two substances form a cocrystal and the atoms of the second component are located in the regular lattice positions of the first component.

[0038] Examples of metal azo pigments (A1) include those described in Japanese Patent Publication No. 2014-12838, Japanese Patent Publication No. 2017-171912, Japanese Patent Publication No. 2017-171913, Japanese Patent Publication No. 2017-171914, Japanese Patent Publication No. 2017-171915, Japanese Patent Publication No. 2022-61494, etc.

[0039] Metal azo pigments (A1) can be used alone or in combination of two or more types.

[0040] In compositions containing a green pigment that tends to absorb ultraviolet light, the UV curability of the coating may decrease. By including a metal azo pigment (A1), the decrease in UV curability can be suppressed, and a cured film with excellent coloring ability and solvent resistance can be obtained. From the viewpoint of color tone and curability, the mass ratio of the green pigment to the metal azo pigment (A1) is preferably 1:0.05 to 1.2.

[0041] The UV-curable inkjet composition of the present invention exhibits excellent storage stability even at high pigment concentrations, and achieves both high ejection performance and solvent resistance. Here, a high pigment concentration means 8% by mass or more of the total mass of the UV-curable inkjet composition. From the viewpoint of ejection performance, the upper limit of the pigment concentration is preferably 18% by mass or less.

[0042] (Other colorants) The UV-curable inkjet composition of the present invention may include, as the colorant (A), other colorants other than green pigment and metal azo pigment (A1). The other colorants can be arbitrarily selected from various conventionally known pigments, pigment derivatives, and dyes. As pigments, organic or inorganic pigments can be used individually or in combination of two or more types. Specific examples of other colorants usable in the present invention are shown below by their color index numbers.

[0043] [Pigments] Examples of yellow pigments include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 12 Examples include pigments described in 3, 126, 127, 128, 129, 138, 139, 147, 150, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 185, 187, 188, 192, 193, 194, 196, 198, 199, 213, 214, 231, 233, and the pigments described in Japanese Patent Publication No. 2012-226110. Preferably, the pigments are CI Pigment Yellow 138, 139, 150, 185, 231, 233, or the pigments described in Japanese Patent Publication No. 2012-226110.

[0044] As the blue pigment, for example, CI Pigment Blue 1, 1:2, 1:3, 2, 2:1, 2:2, 3, 8, 9, 10, 10:1, 11, 12, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 18, 19, 22, 24, 24:1, 53, 56, 56:1, 57, 58, 59, 60, 61, 62, 64, etc., can be used. Among these, from the viewpoint of lightfastness and transmittance, CI Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, or 15:6 is preferred, and CI Pigment Blue 15:2, 15:3, or 15:6 is even more preferred.

[0045] Examples of purple pigments include CI 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, but are not limited to these.

[0046] Examples of red pigments 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, 6 3:1, 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, 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, 235, 236, 237, 238, 239, 242, 243, 245, 247, 249, 250, 251, 253, 254, 255, 256, 257, 258, 259, 260, 262, 2 Red pigments such as 63, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 291, 295, or 296, pigments described in Japanese Patent Publication No. 2014-134712, and pigments described in Japanese Patent Publication No. 6368844 can be used. Among these, CI Pigment Red 122, 177, 254, 264, 266, 269, and 291 are preferred from the viewpoint of coloring power and storage stability.

[0047] As the orange pigment, you can use orange pigments such as CI Pigment Orange 34, 36, 38, 43, 51, 55, 59, 61, 62, 64, 71, or 73.

[0048] Examples of black pigments include C.I. Pigment Black 1, C.I. Pigment Black 7, carbon black, organic black pigment, and titanium black pigment, with carbon black being the preferred choice.

[0049] In addition, inorganic pigments such as titanium dioxide, barium sulfate, zinc oxide, lead sulfate, lead yellow, zinc yellow, red iron(III) oxide, cadmium red, ultramarine, Prussian blue, chromium oxide green, cobalt green, amber, and synthetic iron black can be used. Inorganic pigments are used in combination with organic pigments to ensure good coating properties, sensitivity, and developability while maintaining a balance between saturation and brightness.

[0050] From the viewpoint of the transmittance of the coating film and ejection performance, it is preferable to include at least one colorant selected from red pigment, purple pigment, and black pigment. With the addition of a small amount, the transmittance around 520 nm can be efficiently adjusted, and aggregation of pigments during color mixing is suppressed, resulting in an ultraviolet-curable inkjet composition with good ejection performance.

[0051] [Pigment miniaturization] When the colorant (A) used in the UV-curable inkjet composition of the present invention is a pigment, it is preferable to use it after micronization. The micronization method is not particularly limited, and for example, wet grinding, dry grinding, or dissolution extraction methods can all be used. As exemplified in the present invention, micronization can be performed by salt milling using a kneader method, which is a type of wet grinding. The average primary particle size of the pigment after micronization is preferably in the range of 5 to 90 nm. If it is smaller than 5 nm, dispersion becomes difficult, and if it is larger than 90 nm, the transmittance may decrease. For these reasons, a more preferable average primary particle size is in the range of 10 to 70 nm. The average primary particle diameter is the average value of approximately 200 particles arbitrarily selected from magnified images obtained using a TEM (transmission electron microscope). If a particle has both a major and minor axis, the length of the major axis is used.

[0052] Salt milling is a process in which a mixture of pigment, water-soluble inorganic salt, and water-soluble organic solvent is mechanically kneaded while heated using batch or continuous kneading machines such as kneaders, two-roll mills, three-roll mills, ball mills, attritors, sand mills, and planetary mixers, and then washed with water to remove the water-soluble inorganic salt and water-soluble organic solvent. The water-soluble inorganic salt acts as a crushing aid, and the pigment is crushed by utilizing the high hardness of the inorganic salt during salt milling. By optimizing the conditions for salt milling the pigment, it is possible to obtain pigments with a very fine primary particle size, a narrow distribution width, and a sharp particle size distribution.

[0053] As water-soluble inorganic salts, sodium chloride, barium chloride, potassium chloride, sodium sulfate, etc., can be used, but from a cost standpoint, sodium chloride (table salt) is preferred. From the perspective of both processing efficiency and production efficiency, it is preferable to use 50 to 2000 parts by weight of the water-soluble inorganic salt per 100 parts by weight of pigment, and most preferably 300 to 1000 parts by weight.

[0054] The water-soluble organic solvent serves to wet the pigment and the water-soluble inorganic salt. It is not particularly limited as long as it dissolves (miscible) in water and does not substantially dissolve the inorganic salt used. However, since the temperature rises during salt milling and the solvent is prone to evaporation, a high-boiling-point solvent with a boiling point of 120°C or higher is preferred from a safety standpoint. For example, 2-methoxyethanol, 2-butoxyethanol, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol, diethylene glycol, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol, triethylene glycol monomethyl ether, liquid polyethylene glycol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, liquid polypropylene glycol, etc. are used. The water-soluble organic solvent is preferably used in an amount of 5 to 1000 parts by weight, and most preferably 50 to 500 parts by weight, per 100 parts by weight of pigment.

[0055] When the pigment is subjected to salt milling, a resin may be added as needed. The type of resin used is not particularly limited, and natural resins, modified natural resins, synthetic resins, synthetic resins modified with natural resins, etc., can be used. The resin used is preferably solid at room temperature, insoluble in water, and more preferably partially soluble in the above organic solvent. The amount of resin used is preferably in the range of 5 to 200 parts by weight per 100 parts by weight of pigment.

[0056] [dye] Examples of dyes include acid dyes, direct dyes, basic dyes, salt-forming dyes, oil-soluble dyes, disperse dyes, reactive dyes, mordant dyes, vat dyes, and sulfur dyes. Also included are derivatives of dyes and lake pigments, which are dyes that have been transformed into lakes.

[0057] Acid dyes preferably have acidic groups such as sulfonic acid or carboxylic acid. Direct dyes preferably form salt compounds with an inorganic salt of the acid dye, or with an acid dye and a nitrogen-containing compound such as a quaternary ammonium salt compound, tertiary amine compound, secondary amine compound, or primary amine compound. Salt compounds that are salts of a resin component having these functional groups and an acid dye are also preferred. Furthermore, by sulfonamidating the salt compound to a sulfonic acid amide compound, it is easy to obtain a photosensitive colored composition with excellent resistance (lightfastness, solvent resistance). Furthermore, salt-forming compounds of acid dyes and compounds containing an onium base are also preferred due to their excellent resistance (light resistance and solvent resistance). The compound containing the onium base is preferably a resin having a cationic group.

[0058] Basic dyes include salt-forming compounds made from organic acids, perchloric acid, or metal salts thereof. Among salt-forming compounds, salt-forming compounds of basic dyes are preferred because they have excellent resistance to various substances and compatibility with pigments.

[0059] The chemical structures of dyes include, for example, azo dyes, disazo dyes, azomethine dyes (indoaniline dyes, indophenol dyes, etc.), dipyromethene dyes, quinone dyes (benzoquinone dyes, naphthoquinone dyes, anthraquinone dyes, anthrapyridone dyes, etc.), carbonium dyes (diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, acridine dyes, etc.), and quinoneimine dyes (oxazine dyes). Examples include dyes such as thiazine dyes, azine dyes, polymethine dyes (oxonol dyes, merocyanine dyes, allylidene dyes, styryl dyes, cyanine dyes, squarylium dyes, croconium dyes, etc.), quinophthalone dyes, phthalocyanine dyes, subphthalocyanine dyes, perinone dyes, indigo dyes, thioindigo dyes, quinoline dyes, nitro dyes, nitroso dyes, and rhodamine dyes. Among these, azo dyes, xanthene dyes, cyanine dyes, triphenylmethane dyes, anthraquinone dyes, dipyromethene dyes, squarylium dyes, quinophthalone dyes, phthalocyanine dyes, and subphthalocyanine dyes are preferred from the viewpoint of color characteristics such as hue, color separation, and color unevenness, with xanthene dyes, cyanine dyes, triphenylmethane dyes, anthraquinone dyes, dipyromethene dyes, and phthalocyanine dyes being more preferred. The specific structures of the dyes are described in "New Edition Dye Handbook" (edited by the Society of Synthetic Organic Chemistry; Maruzen, 1970), "Color Index" (The Society of Dyers and colourists), and "Pigment Handbook" (edited by Okawara et al.; Kodansha, 1986), among others.

[0060] [Dye derivatives] In the present invention, the colorant (A) may include a pigment derivative. The pigment derivative is a compound having an acidic group, a basic group, a neutral group, etc., in an organic pigment residue. Examples of pigment derivatives include compounds having acidic substituents such as a sulfo group, a carboxyl group, or a phosphate group, as well as compounds having basic substituents such as amine salts thereof, sulfonamide groups, or tertiary amino groups at the terminal, and compounds having neutral substituents such as a phenyl group or a phthalimidoalkyl group. Examples of organic pigments include diketopyrrolopyrrole pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, perinone pigments, perylene pigments, thiaidine indigo pigments, triazine pigments, benzimidazolone pigments, indole pigments such as benzoisoindole, isoindoline pigments, isoindolinone pigments, quinophthalone pigments, naphthol pigments, surene pigments, metal complex pigments, and azo pigments such as azo, disazo, and polyazo.

[0061] Specifically, diketopyrrolopyrrole dye derivatives are described in Japanese Patent Publication No. 2001-220520, WO2009 / 081930, WO2011 / 052617, WO2012 / 102399, and Japanese Patent Publication No. 2017-156397; phthalocyanine dye derivatives are described in Japanese Patent Publication No. 2007-226161, WO2016 / 163351, Japanese Patent Publication No. 2017-165820, and Japanese Patent No. 5753266; and anthraquinone dye derivatives are described in Japanese Patent Publication No. Japanese Patent Publication No. 63-264674, Japanese Patent Publication No. 09-272812, Japanese Patent Publication No. 10-245501, Japanese Patent Publication No. 10-265697, Japanese Patent Publication No. 2007-079094, Brochure WO2009 / 025325, Quinacridone-based dye derivatives are Japanese Patent Publication No. 48-54128, Japanese Patent Publication No. 03-9961, Japanese Patent Publication No. 2000-273383, Dioxazine-based dye derivatives are Japanese Patent Publication No. 2011-162662, Thiazine-indigo-based dye derivatives are Japanese Patent Publication No. 2007-3147 Japanese Patent Publication No. 85, Triazine-based dye derivatives are described in Japanese Patent Publication No. 61-246261, Japanese Patent Publication No. 11-199796, Japanese Patent Publication No. 2003-165922, Japanese Patent Publication No. 2003-168208, Japanese Patent Publication No. 2004-217842, Japanese Patent Publication No. 2007-314681, Benzoisoindole-based dye derivatives are described in Japanese Patent Publication No. 2009-57478, Quinophthalone-based dye derivatives are described in Japanese Patent Publication No. 2003-167112, Japanese Patent Publication No. 2006-291194, Japanese Patent Publication No. 2008-31281, Japanese Patent Publication No. 2 Examples of dye derivatives include those described in Japanese Patent Publication No. 012-226110, those described in Japanese Patent Publication Nos. 2012-208329 and 2014-5439 for naphthol-based dye derivatives, those described in Japanese Patent Publication Nos. 2001-172520 and 2012-172092 for azo-based dye derivatives, those described in Japanese Patent Publication Nos. 2004-307854 for acidic substituents, and those described in Japanese Patent Publication Nos. 2002-201377, 2003-171594, 2005-181383 and 2005-213404 for basic substituents. In addition, these documents may refer to dye derivatives as derivatives, pigment derivatives, dispersants, pigment dispersants, or simply compounds, but compounds having substituents such as acidic groups, basic groups, or neutral groups on the aforementioned organic dye residues are synonymous with dye derivatives.

[0062] Dye derivatives can be used individually or in combination of two or more types.

[0063] The content of the pigment derivative is preferably 1 to 100 parts by mass, more preferably 3 to 70 parts by mass, and even more preferably 5 to 50 parts by mass, per 100 parts by mass of pigment.

[0064] <Resin (B)> The ultraviolet-curable inkjet composition of the present invention comprises a resin (B). The resin (B) is not particularly limited, but reference can be made to the description in prior art such as Japanese Patent Application Publication No. 2011-225848. Specifically, examples include Lubrizol's SOLSPERSE series (e.g., SOLSPERSE 16000, 21000, 32000, 33000, 41000, J180, J200, etc.), BIC-Chemie's DISPERBYK series (e.g., DISPERBYK 102, 110, 111, 118, 165, 168, 190, etc.), and Evonik's TEGO Dispers series (e.g., TEGO Dispers 610, 630, 651, 655, 750W, 755W, etc.).

[0065] <Polymerizable compound (C)> The ultraviolet-curable inkjet composition of the present invention contains a polymerizable compound (C). While the polymerizable compound (C) is not particularly limited, conventionally known monofunctional, difunctional, and polyfunctional monomers and oligomers with three or more functions can be used. The polymerizable compound (C) may be used alone or in combination of two or more.

[0066] Examples of monofunctional monomers include monofunctional acrylic monomers and monofunctional vinyl monomers. Specific examples of compounds include benzyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, (ethoxylated (or propoxylated)) 2-phenoxyethyl (meth)acrylate, dicyclopentenyl (oxyethyl) (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, 2-methoxyethyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and ethoxyethoxyethyl (meth)acrylate. Acrylate, methoxydipropylene glycol (meth)acrylate, dipropylene glycol (meth)acrylate, nonylphenol EO modified acrylate, nonylphenol PO modified acrylate, o-phenylphenol EO modified acrylate, 2-ethylhexyl EO modified acrylate, β-carboxyethyl (meth)acrylate, trimethylolpropane formal (meth)acrylate, isoamyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isoboronyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth)acrylate Examples include monofunctional acrylic monomers such as acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 1,4-cyclohexanedimethanol (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, acryloylmorpholine, and N-acryloyloxyethylhexahydrophthalimide, as well as monofunctional vinyl monomers such as N-vinylcaprolactam, N-vinylpyrrolidone, and N-vinylformamide. These compounds may be used individually or in combination of two or more.

[0067] Polyfunctional monomers include compounds having two or more polymerizable functional groups within their molecule. Examples include polyfunctional acrylic monomers and vinyl monomers. Examples of specific compounds include dimethylol tricyclodecane di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, and (ethoxylated (or propoxylated)) 1 Examples include 6-isobornyl di(meth)acrylate, 1,9-nonanediol acrylate, 1,10-decanediol diacrylate, (ethoxylated (or propoxylated)) neopentyl glycol di(meth)acrylate, hydroxypivalate neopentyl glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, 2-(2-vinyloxyethoxy)ethyl acrylate, (neopentyl glycol modified) trimethylolpropane di(meth)acrylate, tripropylene glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, pentaerythritol tri(or tetra)(meth)acrylate, trimethylolpropane tri(or tetra)(meth)acrylate, tetramethylolmethane tri(or tetra)(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0068] Another example of a polyfunctional monomer is a polyfunctional vinyl monomer containing multiple vinyl groups within its molecule. Specific examples of compounds include butanediol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, cyclohexanedimethanol divinyl ether, trimethylolpropane divinyl ether, pentaerythritol tri(or tetra)vinyl ether, trimethylolpropanediallyl ether, and pentaerythritol tri(or tetra)allyl ether. These compounds may be used individually or in combination of two or more. Note that "EO modification" refers to ethylene oxide modification, and "PO modification" refers to propylene oxide modification.

[0069] (Monomer (C1)) The polymerizable compound (C) preferably contains monofunctional and / or difunctional monomers (C1) having a viscosity of 10 mPa·s or less at 25°C. From the viewpoint of storage stability and discharge properties, the content of monofunctional and difunctional monomers (C1) is more preferably 70% to 100% by mass of the polymerizable compound (C). Examples of monofunctional and / or bifunctional monomers (C1) with a viscosity of 10 mPa·s or less at 25°C include isobornyl acrylate (viscosity 7.7 mPa·s), benzyl acrylate (viscosity 2.2 mPa·s), 2-phenoxyethyl (meth)acrylate (viscosity 9.0 mPa·s), dipropylene glycol diacrylate (viscosity 8.0 mPa·s), 1,6-hexanediol diacrylate (viscosity 7.0 mPa·s), 1,9-nonanediol diacrylate (viscosity 8.0 mPa·s), cyclohexyl acrylate (viscosity 2.5 mPa·s), and 2-(2-vinyloxyethoxy)ethyl acrylate (viscosity 3.7 mPa·s). Among these, dipropylene glycol diacrylate is preferred from the viewpoint of storage stability and dispersibility.

[0070] In the ultraviolet-curable inkjet composition of the present invention, from the viewpoint of viscosity and filterability, it is preferable to add monomer (C1) when mixing and dispersing colorants and the like, so that it adheres to the surface of the colorants and the like.

[0071] <Polymerization initiator (D)> The ultraviolet-curable inkjet composition of the present invention contains a polymerization initiator (D). The polymerization initiator that can be used in the present invention may be a known polymerization initiator. For example, it is preferable to use a polymerization initiator that generates radicals by molecular cleavage or hydrogen abstraction. In the present invention, polymerization initiator (D) may be used alone or in combination of two or more. Furthermore, a polymerization initiator that generates radicals and a polymerization initiator that generates cations may be used in combination.

[0072] Specific examples of polymerization initiators (D) include 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]-phenyl}-2-methylpropan-1-one, and α-phenylglyoxylic acid methyl esters. Hydroxyalkylphenone compounds; α-aminoalkylphenone compounds such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butanone-1-one, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morphonyl)phenyl]-1-butanone; bis(2,4 Acylphosphine oxide compounds such as ,6-trimethylbenzoyl)-phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide; oxime ester compounds such as 1,2-octanedione, 1-[4-(phenylthio)-2-(O-benzoyl oxime), and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime); benzophenone compounds such as 4-phenylbenzophenone, isophthalphenone, and 4-benzoyl-4'-methyl-diphenyl sulfide;Examples include triazine compounds such as 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-piperonyl-4,6-bis(trichloromethyl)-s-triazine, 2,4-bis(trichloromethyl)-6-styryl-s-triazine, 2-(naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxy-naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2,4-trichloromethyl-(piperonyl)-6-triazine, or 2,4-trichloromethyl-(4'-methoxystyryl)-6-triazine.

[0073] Commercially available products include: α-hydroxyalkylphenone compounds such as Omnirad 127, 184, 1173, 2959 from IGM Resins; aminoalkylphenone compounds such as Omnirad 907, 369E, 379EG from IGM Resins; acylphosphine compounds such as Omnirad 819, TPO from IGM Resins; oxime ester compounds such as IRGACURE OXE-01, 02, 03, 04, 05 from BASF Japan; ADEKA Arclus N-1919, NCI-730, 831E, 930 from ADEKA; and TRONLY TR-PBG-301, 304, 305, 309, 314, 345, 358, 380, 365, 610, 3054, 3057 from Changzhou Strong New Materials Co., Ltd., and IGM Examples include Omnirad 1312, 1314, and 1316 from Resins, SPI-02, 03, 04, 05, 06, and 07 from Samyang Corporation, and DFI-020, 306, and EOX-01 from Daito Chemix. Among these, acylphosphine compounds and / or oxime ester compounds are preferred from the viewpoint of curability.

[0074] (Acylphosphine compounds) Examples of acylphosphine compounds include monoacylphosphine oxides and bisacylphosphine oxides. Examples of monoacylphosphine oxides, though not particularly limited, include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-triethylbenzoyldiphenylphosphine oxide, and 2,4,6-triphenylbenzoyldiphenylphosphine oxide. Examples of bisacylphosphine oxides, though not particularly limited, include bis-(2,4,6-trimethylbenzoyl)-phenylphosphine oxide and bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide. Examples of commercially available acylphosphine compounds include Omnirad TPO (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), Omnirad 819 (bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), and Omnirad TPOL (ethyl(2,4,6-trimethylbenzoyl)-phenylphosphenate).

[0075] (Oxime ester compounds) Oxime ester compounds undergo cleavage of the NO bond in the oxime upon absorption of ultraviolet light, generating iminyl radicals and alkyloxy radicals. These radicals further decompose to produce highly reactive radicals, allowing the ink to cure with less exposure. Oxime ester compounds have high quantum efficiency, resulting in a highly curable coating film with fewer impurities.

[0076] Examples of oxime ester compounds include those described in Japanese Patent Publication No. 2007-210991, Japanese Patent Publication No. 2009-179619, Japanese Patent Publication No. 2010-037223, Japanese Patent Publication No. 2010-215575, Japanese Patent Publication No. 2011-020998, International Publication No. 2021 / 175855, etc.

[0077] The polymerization initiator (D) content in the UV-curable inkjet composition is preferably 1 to 20% by mass, and more preferably 2 to 10% by mass. Adding an appropriate amount further improves photocurability.

[0078] <Solvent> To reduce the viscosity of the UV-curable inkjet composition and improve its wettability on the substrate, a small amount of solvent may be included in the UV-curable inkjet composition. The solvent is selected considering the solubility of each component of the UV-curable inkjet composition, as well as safety. From the viewpoint of curability, the solvent content should be 5.0% or less in the UV-curable inkjet composition. Preferably, the solvent content is 0.1 to 5.0% in the UV-curable inkjet composition, and more preferably 0.2 to 4.0% from the viewpoint of ejection stability.

[0079] The boiling point of the solvent used is preferably 120°C to 300°C, and more preferably 140°C to 270°C. Preferred solvents include glycol compounds such as monoacetates, diacetates, diols, monoalkyl ethers, and dialkyl ethers, as well as lactic acid esters. Among these, glycol compounds such as monoacetates, monoalkyl ethers, and dialkyl ethers are preferred. More specifically, tetraethylene glycol dialkyl ether, ethylene glycol monobutyl ether acetate, and diethylene glycol diethyl ether are preferred.

[0080] <Sensitizer> Furthermore, the ultraviolet-curable inkjet composition of the present invention may contain a sensitizer. Examples of sensitizers include chalcone derivatives, unsaturated ketones such as dibenzalacetone, 1,2-diketone derivatives such as benzyl and camphorquinone, benzoin derivatives, fluorene derivatives, naphthoquinone derivatives, anthraquinone derivatives, xanthene derivatives, thioxanthene derivatives, xanthone derivatives, thioxanthone derivatives, coumarin derivatives, ketocoumarin derivatives, cyanine derivatives, merocyanine derivatives, polymethine dyes such as oxonol derivatives, acridine derivatives, azine derivatives, thiaidine derivatives, oxazine derivatives, indoline derivatives, azulene derivatives, azulenium derivatives, squarylium derivatives, porphyrin derivatives, tetraphenylporphyrin derivatives, triarylmethane derivatives, tetrabenzoporphyrin derivatives, and tetrapyradinoporphyrazine derivatives. Examples include phthalocyanine derivatives, tetraazaporphyrazine derivatives, tetraquinoxaliloporphyrazine derivatives, naphthalocyanine derivatives, subphthalocyanine derivatives, pyrylium derivatives, thiopyrillium derivatives, tetraphylline derivatives, annulene derivatives, spiropyran derivatives, spirooxazine derivatives, thiospilopyran derivatives, metal arene complexes, organic ruthenium complexes, or Michler ketone derivatives, α-acyloxyesters, acylphosphine oxides, methylphenylglyoxylates, benzyl, 9,10-phenanthrenequinone, camphorquinone, ethyl anthraquinone, 4,4'-diethylisophthalophenone, 3,3' or 4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 4,4'-bis(diethylamino)benzophenone, and the like.

[0081] Among the sensitizers mentioned above, thioxanthone derivatives, Michler ketone derivatives, and carbazole derivatives are particularly suitable for sensitizing. More specifically, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 1-chloro-4-propoxythioxanthone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(ethylmethylamino)benzophenone, N-ethylcarbazole, 3-benzoyl-N-ethylcarbazole, 3,6-dibenzoyl-N-ethylcarbazole, etc., can be used.

[0082] More specifically, examples of sensitizers include, but are not limited to, those described in "Pigment Handbook" (1986, Kodansha) edited by Shin Okawara et al., "Chemistry of Functional Pigments" (1981, CMC) edited by Shin Okawara et al., and "Special Functional Materials" (1986, CMC). In addition, sensitizers that exhibit absorption in the ultraviolet to near-infrared region can also be included. Sensitizers can be used alone or in combination of two or more types.

[0083] <Polymerization inhibitor> The UV-curable inkjet composition of the present invention may use polymerization inhibitors to enhance storage stability over time, ejection stability after time, and storage stability within an inkjet recording device. Hindered phenol compounds, phenothiazine compounds, hindered amine compounds, and phosphorus compounds are particularly preferred as polymerization inhibitors. Specifically, examples include 4-methoxyphenol, hydroquinone, methylhydroquinone, t-butylhydroquinone, 2,6-di-t-butyl-4-methylphenol, phenothiazine, and aluminum salts of N-nitrosophenylhydroxylamine. From the viewpoint of enhancing stability over time while maintaining curability, it is preferable to incorporate the polymerization inhibitor at a ratio of 0.01 to 2% by mass of the total UV-curable inkjet composition.

[0084] <Antioxidant> The UV-curable inkjet composition of the present invention may contain an antioxidant. The antioxidant prevents the polymerization initiator (D) contained in the UV-curable inkjet composition from oxidizing and yellowing, thereby improving the transmittance of the coating film.

[0085] Examples of antioxidants include hindered phenol, hindered amine, phosphorus, sulfur, and hydroxylamine compounds. In this invention, it is preferable that the antioxidant is a compound that does not contain halogen atoms.

[0086] Among these, hindered phenol-based antioxidants, hindered amine-based antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants are preferred from the viewpoint of achieving both the transmittance and sensitivity of the coating film.

[0087] Antioxidants can be used alone or in combination of two or more types.

[0088] Furthermore, an antioxidant content of 0.5 to 5.0% by mass of 100% by mass of the solid content of the UV-curable inkjet composition is more preferable because it results in good transmittance and spectral characteristics.

[0089] <Surface modifier> In this specification, a surface modifier refers to a substance that, when added, reduces the surface tension of the ink. Examples of surface modifiers include silicone-based surface modifiers, fluorine-based surface modifiers, acrylic-based surface modifiers, and acetylene glycol-based surface modifiers. From the viewpoint of surface tension reduction ability and compatibility with polymerizable compounds (C), it is preferable to use a silicone-based surface modifier.

[0090] Specific examples of silicone-based surface modifiers include modified dimethylsiloxane skeletons. Among these, polyether-modified siloxane-based surface modifiers are preferred. The polyether may be, for example, polyethylene oxide and polypropylene oxide. In one embodiment of the present invention, commercially available polyether-modified silicone surfactants can be used. Examples of suitable and representative products include polyether-modified siloxanes such as BYK(registered trademark)-378, 348, and 349 from BIC-Chemie, as well as polyether-modified polydimethylsiloxanes such as BYK-UV3500 and UV3510. Also, polyether-modified siloxane copolymers such as TEGO(registered trademark)GLIDE450, 440, 435, 432, 410, 406, 130, 110, and 100 from Evonik Degussa are used. Among these, polyether-modified silicone-based surface modifiers such as BYK-331, 378, 348, UV3510, TEGOGLIDE 450, 440, 432, and 410 are preferred from the viewpoint of achieving good image quality.

[0091] The content of the silicone-based surface modifier is preferably in the range of 0.1% by mass or more and less than 5.0% by mass, relative to the total amount of the UV-curable inkjet composition. By setting the content to 0.1% by mass or more, the wettability of the UV-curable inkjet composition to the substrate can be easily improved. On the other hand, by setting the content to less than 5.0% by mass, it becomes easier to ensure the storage stability of the UV-curable inkjet composition.

[0092] <Storage stabilizer> The UV-curable inkjet composition of the present invention may contain a storage stabilizer to stabilize the viscosity of the composition over time. Examples of storage stabilizers include benzyl trimethyl chloride, quaternary ammonium chlorides such as diethylhydroxyamine, organic acids such as lactic acid and oxalic acid and their methyl ethers, organic phosphines such as t-butyl pyrocatechol, tetraethylphosphine, and tetraphenylphosphine, and phosphates. The storage stabilizer can be used in an amount of 0.1 to 10% by mass, based on the total amount of the colorant (A) (100% by mass).

[0093] <Other ingredients> The ultraviolet-curable inkjet composition of the present invention may contain other components besides those listed above. Examples of other components include thermal crosslinking agents, curing agents, curing accelerators, acid generators, curing catalysts, chain transfer agents, silane coupling agents, and near-infrared absorbers. The content of these other components can be appropriately set within a range that solves the problems of the present invention.

[0094] <Method for preparing UV-curable inkjet compositions> The UV-curable inkjet composition of the present invention can be prepared by further diluting a colorant dispersion, which is produced by finely dispersing a colorant (A) together with a colorant carrier such as a resin (B) and a polymerizable compound (C) using various dispersion methods such as a kneader, a two-roll mill, a three-roll mill, a ball mill, a horizontal sand mill, a vertical sand mill, an annular bead mill, or an attritor, by adding a polymerizable compound (C), a polymerization initiator (D), etc. When preparing the colorant dispersion, two or more colorants may be dispersed simultaneously on the colorant carrier, or they may be dispersed separately on the colorant carrier and then mixed. If the colorant has high solubility, such as a dye, specifically if it has high solubility in the polymerizable compound (C) used and dissolves upon stirring without the presence of foreign matter, then it is not necessary to prepare it by fine dispersion as described above.

[0095] <Water content> From the viewpoint of stability, the UV-curable inkjet composition of the present invention preferably contains 2.0% by mass or less of water.

[0096] The water content in the UV-curable inkjet composition is more preferably 1.5% by mass or less, and particularly preferably 1.0% by mass or less. Furthermore, the lower limit of the water content is preferable as much as possible, but there are no particular restrictions.

[0097] There are no particular restrictions on the method for controlling the water content, and known methods can be used. For example, each of the above-mentioned components can be thoroughly dried to reduce the amount of water contained in the components before use. Another example is a method of producing an ultraviolet-curable inkjet composition while blowing in dry air, an inert gas, or a mixture thereof.

[0098] <Specific metal atoms> The UV-curable inkjet composition of the present invention may contain small amounts of metal components, including Li, Na, Mg, K, Cs, Co, Ca, Fe, Si, and Zr (hereinafter also referred to as specific metal atoms), in addition to the components of the colorant (A), resin (B), polymerizable compound (C), and polymerization initiator (D). If a large amount of these metal components containing specific metal atoms is present, storage stability may be impaired, heat resistance may decrease, and ejection performance may deteriorate. Furthermore, color filters made using UV-curable inkjet compositions containing a large amount of metal components, including such specific metal atoms, may generate foreign matter, which can easily lead to a decrease in transmittance. Preferably, the total content of specific metal atoms in the metal components of the UV-curable inkjet composition of the present invention is 1 to 1000 ppm by mass relative to the entire UV-curable inkjet composition.

[0099] <Average dispersed particle size> The average dispersed particle diameter (secondary particle diameter) of particles in the UV-curable inkjet composition is preferably 30 to 300 nm, and more preferably 40 to 250 nm. Having an appropriate particle diameter makes it easier to obtain a UV-curable inkjet composition with high storage stability.

[0100] The method for measuring the average dispersed particle diameter (secondary particle diameter) uses, for example, Nikkiso's Microtrac UPA-EX150, which employs dynamic light scattering (FFT power-spectrum method), with particle permeability set to absorption mode, particle shape to non-spherical, and D50 particle diameter as the average diameter. The diluent solvent used for measurement is the same solvent used for dispersion, and it is preferable to measure immediately after sample preparation of ultrasonically treated samples to obtain results with less variation.

[0101] <Removal of coarse particles> It is preferable to remove coarse particles of 5 μm or larger, preferably 1 μm or larger, more preferably 0.5 μm or larger, and any mixed dust from the UV-curable inkjet composition by means of centrifugal separation, sintering filters, or membrane filters. The UV-curable inkjet composition of the present invention preferably contains substantially no particles of 0.5 μm or larger, and more preferably contains no particles of 0.3 μm or smaller.

[0102] <Viscosity> The UV-curable inkjet composition of the present invention is preferably adjusted to have a viscosity of 5 to 50 mPa·s at 25°C. Within this viscosity range, excellent ejection responsiveness and stability are achieved.

[0103] <Cured film> The cured film of the present invention is formed by the ultraviolet-curable inkjet composition of the present invention. The cured film may be used in a laminated state on a substrate, or the cured film may be peeled off from the substrate. The method for manufacturing the cured film is not particularly limited, and known methods can be used. For example, the ultraviolet-curable inkjet composition of the present invention can be printed on a substrate using the printing method described later to manufacture the film.

[0104] Examples of substrates include those made of materials such as glass, resin, and silicon. An organic light-emitting layer may be formed on these substrates. An image sensor such as a CCD or CMOS may also be formed on the substrate. Furthermore, a primer layer may be provided on the substrate as needed to improve adhesion with the upper layer, prevent diffusion of materials, and flatten the substrate surface.

[0105] <Printing method> There are two types of inkjet printing methods: one-pass printing and multi-pass printing. In the one-pass printing method, multiple inkjet heads are fixedly positioned within a predetermined printing area. This is a method of printing with a single head scan. In contrast, the multi-pass printing method (serial) Also known as the print method, this method prints a predetermined print area using multiple head scans. Therefore, the UV-curable inkjet composition of the present invention has excellent curability and can be used in a single-pass printing method.

[0106] The optimal film thickness is preferably 1 μm to 30 μm, more preferably 2 μm to 25 μm, and even more preferably 3 μm to 20 μm. Within this range, good color development and excellent curing properties are obtained.

[0107] (Inkjet head) Inkjet heads used in inkjet printing include on-demand printing heads. Either a continuous or sequential discharge method is acceptable. Specific examples of discharge methods include electromechanical conversion methods (e.g., single-cavity type, double-cavity type, bender type, piston type, shear-mode type, shear-wall type, etc.), electro-thermal conversion methods (e.g., thermal inkjet type, bubble jet (registered trademark) type, etc.), electrostatic attraction methods (e.g., electric field control type, slit jet type, etc.), and discharge methods (e.g., spark jet type, etc.), but any of these discharge methods may be used.

[0108] (Ink droplet size) The volume of ink droplets ejected from the inkjet head is preferably in the range of 0.5 to 100 pL. More preferably, it is in the range of 2 to 20 pL, from the viewpoint of minimizing uneven coating and enabling high printing speeds.

[0109] In a single-pass printing method, it is preferable to use a wide head in which nozzles are arranged in a width greater than or equal to the width of the desired coating pattern. When forming multiple independent coating patterns on the same substrate that are not continuous with each other, it is sufficient to use a wide head that is at least greater than the width of each coating pattern.

[0110] The active energy ray used to cure the inkjet composition can be any ultraviolet light that can affect the electron orbitals of the irradiated object and induce polymerization reactions such as radicals, cations, and anions.

[0111] Specific examples of ultraviolet light sources that can be used include high-pressure mercury lamps, metal halide lamps, low-pressure mercury lamps, ultra-high-pressure mercury lamps, ultraviolet lasers, LEDs, and sunlight. From the standpoint of convenience and cost, it is preferable to use high-pressure mercury lamps, metal halide lamps, and LEDs. The emission maximum wavelength is preferably 200 to 600 nm, more preferably 300 to 450 nm, even more preferably 320 to 420 nm, and particularly preferably ultraviolet light in the range of 340 to 400 nm.

[0112] <Color Filter> The color filter of the present invention comprises a substrate and a cured film of the present invention. The color filter of the present invention comprises at least one red filter segment, at least one green filter segment, and at least one blue filter segment. Furthermore, in addition to the above three color filter segments, it may also comprise a yellow filter segment. It is preferable that the cured film formed using the UV-curable inkjet composition of the present invention is a color filter used in the green filter segment.

[0113] <How to manufacture color filters> The color filter of the present invention can be manufactured by printing.

[0114] The formation of filter segments by printing is a low-cost and highly mass-producible method for manufacturing color filters, as patterns can be created by printing UV-curable inkjet compositions. Furthermore, advancements in printing technology enable the printing of fine patterns with high dimensional accuracy and smoothness. Controlling the fluidity of the composition on the printing press is also important, and the viscosity of the composition can be adjusted using dispersants and extender pigments.

[0115] <Solid-state image sensor> The solid-state image sensor of the present invention has a color filter of the present invention. The form used in the solid-state image sensor is not particularly limited, but for example, it has a substrate on which a plurality of photodiodes constituting the light-receiving area of ​​the solid-state image sensor (CCD image sensor, CMOS image sensor, etc.) and transfer electrodes made of polysilicon or the like are provided, a light-shielding film with an opening only for the light-receiving portion of the photodiode is provided on the photodiode and transfer electrodes, a device protective film made of silicon nitride or the like is provided on the light-shielding film so as to cover the entire surface of the light-shielding film and the light-receiving portion of the photodiode, and a filter is provided on the device protective film. Furthermore, there may be a configuration in which a light-gathering means (e.g., a microlens, etc.; the same applies hereinafter) is provided on the device protective film and below the filter (on the side closer to the substrate), or a configuration in which the light-gathering means is provided on the filter. In addition, the filter may have a structure in which a hardened film forming each colored pixel is embedded in a space partitioned, for example, in a grid pattern by partitions. In this case, it is preferable that the partitions have a low refractive index with respect to each colored pixel. The imaging device equipped with the solid-state image sensor of the present invention can be used in a variety of applications, such as digital cameras, electronic devices with imaging functions (smartphones, tablet terminals, etc.), in-vehicle cameras, surveillance cameras, and optical sensors.

[0116] <Image display device> The image display device of the present invention has the color filter of the present invention. Examples of image display devices include liquid crystal displays and organic EL displays. The form in which it is used in the image display device is not particularly limited, but it can be used as a color filter, black matrix, light-shielding filter, infrared cut filter, or infrared transmission filter. The form used in the image display device is not particularly limited, as long as it functions as an image display device. For example, the configuration described in "Next-Generation Liquid Crystal Display Technology" (by Tatsuo Uchida, published by Kogyo Chosakai Co., Ltd. in 1994) is one such example. For definitions of image display devices and details of various image display devices, see, for example, "Electronic Display Devices" (by Akio Sasaki, Kogyo Chosakai Co., Ltd., published in 1990) and "Display Devices" (by Junsho Ibuki, Sangyo Tosho Co., Ltd., published in 1989). [Examples]

[0117] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to these examples. Note that "parts" refers to "parts by mass" and "%" refers to "percentage by mass".

[0118] (Weight-average molecular weight (Mw) of the resin) The weight-average molecular weight (Mw) of the resin is the weight-average molecular weight (Mw) in polystyrene terms, measured using a TSKgel column (Tosoh Corporation) and a GPC (Tosoh Corporation, HLC-8120GPC) equipped with an RI detector, with a 3 mM triethylamine and 10 mM LiBr N,N-dimethylformamide solution as the developing solvent.

[0119] (Amine value of resin) The amine value of the resin was determined by potentiometric titration using a 0.1 N hydrochloric acid aqueous solution, and then converted to the equivalent amount of potassium hydroxide. The amine value of the resin represents the amine value of the non-volatile components.

[0120] (Quaternary ammonium salt value of resins) The quaternary ammonium salt value of the resin was determined by titration with a 0.1N silver nitrate aqueous solution using a 5% potassium chromate aqueous solution as an indicator, and then converted to the equivalent amount of potassium hydroxide. The quaternary ammonium salt values ​​of the dispersants listed below represent the quaternary ammonium salt values ​​of the non-volatile components.

[0121] (Synthesis of resin (B-1)) In a reaction vessel equipped with a stirrer and thermometer, 41 parts of N,N-dimethylpropanediamine and 120 parts of chloroform were charged and stirred at room temperature. 50 parts of methacrylate chloride were then added dropwise over 1 hour. After stirring at room temperature for 3 hours, 1 After confirming the completion of the reaction by 1H-NMR, the reaction solution was sequentially washed with 300 parts of deionized water and 200 parts of saturated saline solution. Then, 20 g of magnesium sulfate was added to the organic layer, stirred, and filtered. The solvent in the resulting solution was removed using a rotary evaporator, yielding 58 parts of compound [B] represented by the following formula (15) as a pale yellow transparent liquid (yield 85%). The identification of the obtained compound was as follows: 1 The analysis was performed using 1H-NMR.

[0122] Formula (15) [ka]

[0123] In a reaction vessel equipped with a gas inlet pipe, condenser, stirring blades, and thermometer, 15.7 parts of methyl methacrylate, 47.2 parts of n-butyl methacrylate, and 13.2 parts of tetramethylethylenediamine were charged, and the mixture was stirred at 50°C for 1 hour while flowing nitrogen to purge the system with nitrogen. Next, 2.6 parts of ethyl bromoisobutyrate, 5.6 parts of cuprous chloride, and 100 parts of propylene glycol monomethyl ether acetate (hereinafter referred to as PGMAc) were charged, and the temperature was raised to 110°C under a nitrogen stream to start polymerization of the first block. After 4 hours of polymerization, the polymerization solution was sampled and the solid content was measured, and it was confirmed that the polymerization conversion rate was 98% or higher, calculated from the non-volatile content. Next, 25 parts of PGMAc and 30.3 parts of compound [B] as the second block monomer were added to the reaction vessel, and the reaction was continued while stirring at 110°C under a nitrogen atmosphere. Two hours after adding compound [B] represented by formula (15) above, the polymerization solution was sampled and the solid content was measured, and it was confirmed that the polymerization conversion rate of the second block was 98% or higher, calculated from the non-volatile content. Furthermore, 6.8 parts of benzyl chloride were added to this reaction apparatus, and the mixture was stirred for 3 hours while maintaining a temperature of 110°C and a nitrogen atmosphere, after which it was cooled. The previously synthesized block copolymer solution was vacuum-dried at 40°C to obtain resin (B-1), a white powder with an amine value of 70 mgKOH / g, a quaternary ammonium salt value of 30 mgKOH / g, and a weight-average molecular weight (Mw) of 9,800.

[0124] <Method for manufacturing yellow micronized pigment> Azobarbituric acid precursor was prepared according to the synthesis method described in Japanese Patent Publication No. 2017-171915. (Instructions 1) 46.2 g of diazobarbituric acid and 38.4 g of barbituric acid were introduced into 1100 g of distilled water at 85°C. The pH was then adjusted to approximately pH 5 using an aqueous potassium hydroxide solution, and stirring was continued for 90 minutes.

[0125] (Yellow pigment (Y-1)) The azobarbituric acid (0.3 mol) prepared in Instruction 1 was mixed with 1500 parts of distilled water at 82°C. Then, 10 parts of 30% hydrochloric acid was added dropwise to adjust the pH to 2-2.5. After that, 79.4 parts of melamine (0.63 mol) were added. Next, 0.3 mol of approximately 25% nickel chloride solution was added dropwise. After 3 hours at 82°C, the pH was adjusted to approximately 5.5 using KOH. Subsequently, the mixture was diluted with approximately 100 parts of distilled water at 90°C. Then, 21 parts of 30% hydrochloric acid were added dropwise, and the temperature was maintained at 90°C for 12 hours. After that, the pH was adjusted to approximately 5 using potassium hydroxide solution. Next, the pigment was isolated on a suction filter, washed, dried in a vacuum drying cabinet at 80°C, and ground in a standard laboratory mill for 2 minutes. (Yellow pigment (Y-1) = Adduct of nickel azobarbituric acid and melamine).

[0126] (Yellow pigment (Y-2)) Yellow pigment (Y-2) was obtained in the same manner as yellow pigment (Y-1), except that the "0.3 moles of approximately 25% strength nickel chloride solution" in the example of yellow pigment (Y-1) was replaced with "a mixed solution of 0.225 moles of 25% strength nickel chloride + 0.075 moles of 25% strength copper(II) chloride". (Yellow pigment (Y-2) = Melamine adduct of copper / nickel azobarbituric acid, a hybrid compound having 25 mol% copper and 75 mol% nickel components)

[0127] (Yellow pigment (Y-3)) Yellow pigment (Y-3) was obtained in the same manner as yellow pigment (Y-2), except that the "0.3 moles of approximately 25% strength nickel chloride solution" in the production example of yellow pigment (Y-1) was replaced with "a mixed solution of 0.150 moles of 25% strength nickel chloride + 0.150 moles of 25% strength zinc chloride". (Yellow pigment (Y-3) = a hybrid compound having a melamine adduct of zinc / nickel azobarbituric acid, 25 mol% Zn, and 75 mol% Nickel components.)

[0128] (Yellow pigment (Y-4)) Yellow pigment (Y-4) was obtained in the same manner as yellow pigment (Y-2), except that the "0.3 moles of approximately 25% strength nickel chloride solution" in the production example of yellow pigment (Y-1) was replaced with "a mixed solution of 0.075 moles of 25% strength nickel chloride + 0.225 moles of 25% strength zinc chloride". (Yellow pigment (Y-4) = a hybrid compound having a melamine adduct of zinc / nickel azobarbituric acid, with 50 mol% Zn and 50 mol% Nickel components.)

[0129] (Yellow finely processed pigment (A1-1)) 100 parts of yellow pigment (Y-1), 1000 parts of sodium chloride, and 120 parts of diethylene glycol were placed in a stainless steel 1-gallon kneader (manufactured by Inoue Seisakusho) and kneaded at 70°C for 8 hours. This mixture was added to 2000 parts of warm water and stirred in a high-speed mixer for about 1 hour while being heated to about 80°C to form a slurry. After repeated filtration and washing with water to remove salt and solvent, the mixture was dried at 80°C for 24 hours to obtain finely ground yellow pigment (A1-1).

[0130] (Yellow finely processed pigment (A1-2)) Except for replacing yellow pigment (Y-1) with yellow pigment (Y-2), the manufacturing process was carried out in the same manner as for yellow micronized pigment (A1-1) to obtain yellow micronized pigment (A1-2).

[0131] (Yellow finely processed pigment (A1-3)) Except for replacing yellow pigment (Y-1) with yellow pigment (Y-3), the manufacturing process was carried out in the same manner as for yellow micronized pigment (A1-1) to obtain yellow micronized pigment (A1-3).

[0132] (Yellow finely processed pigment (A1-4)) Except for replacing yellow pigment (Y-1) with yellow pigment (Y-4), the manufacturing process was carried out in the same manner as for yellow micronized pigment (A1-1) to obtain yellow micronized pigment (A1-4).

[0133] <Manufacturing of UV-curable inkjet compositions> [Manufacturing Example 1] (Pigment dispersion (d-1)) A pigment dispersion (d-1) was prepared by uniformly stirring and mixing a mixture of the following compositions using a high-speed mixer or the like, and then dispersing the resulting mill base in a horizontal sand mill for approximately 2 hours. Yellow finely processed pigment (A1-1) 18.5 parts Pigment derivative 1: 1.5 parts SOLSPERSE32000 8.0 copies Dipropylene glycol diacrylate 72.0 parts

[0134] [Manufacturing Examples 2-27] (Pigment dispersions (d-2) to (d-27)) Pigment dispersions (d-2) to (d-27) were prepared in the same manner as pigment dispersion (d-1), except that the colorant (A), pigment derivative, resin (B), and polymerizable compound (C) were changed to the compositions and amounts shown in Table 1.

[0135] [Table 1]

[0136] Meaning of Abbreviations in Table 1 <Coloring agent (A)> • "PY138"; CI Pigment Yellow 138 • "PY139"; CI Pigment Yellow 139 • "PG59"; CI Pigment Green 59 • "PG58"; CI Pigment Green 58 • "PG36"; CI Pigment Green 36 • "PG7"; CI Pigment Green 7 • "PG62"; CI Pigment Green 62 • "PG15:1"; CI Pigment Green 15:1 • "PG15:3"; CI Pigment Green 15:3 • "PG15:6"; CI Pigment Green 15:6 • "PR177"; CI Pigment Red 177 • "PV23"; CI Pigment Violet 23 • "Black"; Carbon Black • "PY185"; CI Pigment Yellow 185 • "PY180"; CI Pigment Yellow 180 • "PR122"; CI Pigment Red 122 • "PR254"; CI Pigment Red 254 • Pigment derivative 1 [ka] • "SP5000"; Ammonium copper phthalocyanine sulfonate salt "Solspers 5000" (manufactured by Lubrizol Japan Co., Ltd.) <Resin (B)> • "SP32000"; Basic pigment dispersion resin "Solspers 32000" (manufactured by Lubrizol Japan Co., Ltd.) • "PX4701"; Basic pigment dispersion resin "EFKA PX4701" (manufactured by BASF) • "BYK2013"; Basic pigment dispersion resin "DISPERBYK-2013" (manufactured by BYK Corporation) <Polymerizable compound (C)> • DPGDA: Dipropylene glycol diacrylate manufactured by Arkema (Viscosity at 25°C: 8.0 mPa·s) • PEA: Phenoxyethyl acrylate manufactured by MIWON Corporation (Viscosity at 25°C: 9.0 mPa·s) • CHA: Cyclohexyl acrylate manufactured by Osaka Organic Industries Co., Ltd. (Viscosity at 25°C: 2.5 mPa·s) • PEG200DA: Polyethylene glycol 200 diacrylate manufactured by Arkema. (Viscosity at 25°C: 20.0 mPa·s) IBXA: Isobornyl acrylate manufactured by Arkema. (Viscosity at 25°C: 7.7 mPa·s)

[0137] [Example 1] (UV-curable inkjet composition (D-1)) To achieve the formulations shown in Table 2, a mixture of polymerizable compound, photopolymerization initiator, and stabilizer was slowly added to the previously prepared pigment dispersion, and the resulting mixture was stirred. Next, a surface tension modifier was added to the mixture, and it was shaken in a shaker for 6 hours. After that, the composition was filtered through a PTFE filter with a pore diameter of 0.5 microns to remove dust and coarse particles, and ultraviolet-curable inkjet composition (D-1) was obtained. Note that the order in which the raw materials are added and mixed to obtain the above mixture may not be significant.

[0138] [Examples 2-56, Comparative Examples 1-5] Except for the material types and masses as described in Tables 2-1 to 2-4, UV-curable inkjet compositions (D-2) to (D-61) were prepared in the same manner as UV-curable inkjet composition (D-1).

[0139] [Table 2-1]

[0140] [Table 2-2]

[0141] [Table 2-3]

[0142] [Table 2-4]

[0143] [Polymerizable compound (C1-1)] C1-1-1: Cyclohexyl acrylate manufactured by Osaka Organic Industries Co., Ltd. (viscosity 2.5 mPa·s at 25°C) C1-1-2: Isobornyl acrylate manufactured by Arkema (viscosity 7.7 mPa·s at 25°C) C1-1-3: Benzyl acrylate manufactured by MIWON (viscosity 2.2 mPa·s at 25°C) C1-1-4: 1,6-Hexanediol diacrylate manufactured by Arkema (viscosity 7.0 mPa·s at 25°C) C1-1-5: Methyl 2-allyloxymethylacrylate manufactured by Nippon Shokubai Co., Ltd. (viscosity at 25°C: 1.6 mPa·s) The compounds (C1-1-1) to (C1-1-5) were mixed in a mass ratio of 3:3:1:1:1 to obtain the polymerizable compound (C1-1). • DPGDA: Dipropylene glycol diacrylate manufactured by Arkema (Viscosity at 25°C: 8.0 mPa·s) • PEA: Phenoxyethyl acrylate manufactured by MIWON Corporation (Viscosity at 25°C: 9.0 mPa·s) • VEEA: 2-(2-vinyloxyethoxy)ethyl acrylate manufactured by Nippon Shokubai Co., Ltd. (Viscosity at 25°C: 3.7 mPa·s) • PEG200DA: Polyethylene glycol 200 diacrylate manufactured by Arkema. (Viscosity at 25°C: 20.0 mPa·s) <Stabilizer> ·BHT: “H-BHT” manufactured by Honshu Kagaku Co., Ltd. • Phenothiazine: "Phenothiazine" manufactured by Seiko Chemical Co., Ltd. <Surface modifier> • BYK-UV3510: BYK Corporation, polyether-modified polydimethylsiloxane <Polymerization initiator (D)> • Omnirad819: Manufactured by IGM Resins, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide • OmniradTPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, manufactured by IGM Resins. • Omnirad369: Manufactured by IGM Resins, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 • SpeedCure BMS: 4-Benzoyl-4'-methyl-diphenyl sulfide, manufactured by Sartmar Asia. • Irgacure OXE-04: Manufactured by BASF • D-1: The following compounds [ka] ·D-2: The following compounds [ka] <solvent> • DEDG: Diethylene glycol diethyl ether • Butycel acetate: Ethylene glycol monobutyl ether acetate

[0144] <Evaluation method for UV-curable inkjet compositions> The UV-curable inkjet compositions prepared in each example and comparative example were printed on a glass substrate using a single-pass inkjet printer (OnePass Jet, manufactured by Tritech Co., Ltd.) equipped with an inkjet ejection mechanism featuring a Kyocera head (KJ4A), a mechanism for transporting the ink-deposited substrate at a desired speed, and a mechanism for subsequent irradiation with a UV lamp. The prints were performed under conditions of 14 pl droplet volume and 600 × 600 dpi, and various properties were evaluated. An experimental 385 nm UV-LED irradiator (manufactured by CCS Corporation) was used as the exposure device, with an exposure energy of 1000 mJ / cm². 2 The material was cured by irradiation under the specified exposure conditions, and a sample of the cured film was prepared. The printing speed and printed image were changed for each performance evaluation. The results are shown in Tables 3-1 to 3-4.

[0145] [Storage stability] The viscosity of the obtained UV-curable inkjet composition was measured and defined as the initial viscosity. Furthermore, an accelerated viscosity test was performed, consisting of a cycle of 7 days at 40°C, 7 days at 13°C, and 7 days at 40°C, and the accelerated viscosity over time was measured. The rate of change due to accelerated aging was calculated as accelerated aging viscosity / initial viscosity, and evaluated according to the following criteria. ◎: Change rate less than 5% ○: Change rate of 5% or more but less than 10% △: Change rate between 10% and less than 20% ×: Change rate of 20% or more

[0146] [Curability] A UV-curable inkjet composition was printed onto a 100mm x 100mm, 0.5mm thick glass substrate using an inkjet printer, and a sample of the cured film was obtained. The degree of curing was determined from the printing speed at which the printed cured film cured in one pass, with the conveyor speed varied from 20 to 75 m / min. Curing was determined when the uncured UV-curable inkjet composition no longer adhered to a cotton swab. The evaluation criteria are as follows, with ○ or higher indicating good curing. ◎: Cures at a rate of 50 m / min or more. ○: Cures at a rate of 35 m / min or more but less than 50 m / min. △: Cures at a rate of 20 m / min or more but less than 35 m / min. ×: Does not harden at less than 20 m / min

[0147] [Discharge stability] The prepared UV-curable inkjet composition was used to print a nozzle check pattern using an inkjet printer. After 100,000 prints, the nozzle check pattern was printed again, and the ejection performance was evaluated based on the number of nozzle failures. The evaluation criteria were as follows: The conveyor speed was set to 35 m / min. ◎: No nozzle clogging after 100,000 prints. ○: 1-2 nozzle failures after 100,000 prints. △: 3-5 nozzles per 100,000 prints. ×: More than 6 nozzle failures after 100,000 prints.

[0148] [Coloring power] A UV-curable inkjet composition was printed onto a 100mm x 100mm, 0.5mm thick glass substrate using an inkjet printer to obtain a cured film with a thickness such that the y value in the XYZ color system becomes 0.597 when a C light source is used as the backlight. The thickness of the obtained cured film was measured using a Dektak 3030 (manufactured by Nippon Vacuum Technology Co., Ltd.). The evaluation was performed according to the following criteria. The thinner the film thickness, the higher the coloring power. ○: When y becomes 0.597, the thickness is less than 8.0 μm, indicating good film thickness. △: A usable film thickness when y is 0.597, where the thickness is 8.0 μm or more and less than 10.0 μm. ×: When y becomes 0.597, the thickness is 10.0 μm or more, which is an impractical film thickness.

[0149] [Solvent resistance] The cured films used for evaluating coloring strength were immersed in propylene glycol monomethyl ether acetate for 30 minutes, washed with deionized water, air-dried, and then observed and evaluated using an optical microscope. The evaluation criteria are as follows. ○: No particular changes are observed in the appearance (good) △: Slight changes are visible in the appearance (still usable). ×: Fading occurs (unusable)

[0150] [Table 3-1]

[0151] [Table 3-2]

[0152] [Table 3-3]

[0153] [Table 3-4]

[0154] The results in Tables 3-1 to 3-4 show that Examples 1 to 56 exhibited high coloring power, excellent storage stability, good discharge properties, curability, and solvent resistance.

[0155] A color filter was created by printing with the ultraviolet-curable inkjet composition of the present invention. Due to its excellent properties, the resulting color filter is expected to be suitably used in solid-state image sensors, image display devices, and the like.

Claims

1. A UV-curable inkjet composition comprising a colorant (A), a resin (B), a polymerizable compound (C), and a polymerization initiator (D), The coloring agent (A) comprises a green pigment and a metal azo pigment (A1) containing the compounds represented by (a) and (b) below. A UV-curable inkjet composition having a solvent content of 5.0% or less. (a) Compounds of general formula (1) or its tautomers. 【Chemistry 1】 General formula (1) (In general formula (1), R １ and R ２ each independently represent OH, NH ２ , or NHR ５ . R ３ and R ４ each independently represent O, or NR ５ . R ５ represents a hydrogen atom or an alkyl group which may have a substituent. Me is two or more divalent metal ions selected from the group consisting of Ni ２＋ , Zn ２＋ , Cu ２＋ , and (a) Based on 1 mole of the total amount of compounds, Ni ２＋ , Zn ２＋ , and Cu ２＋ The total amount of ions is 95-100 mol%. (b) Compounds represented by general formula (2) 【Chemistry 2】 General formula (2) (In general formula (2), three R ６ Each of these independently represents a hydrogen atom or an alkyl group which may have substituents.

2. The ultraviolet-curable inkjet composition according to claim 1, wherein the green pigment is at least one selected from C.I. Pigment Green 36, C.I. Pigment Green 58, and C.I. Pigment Green 59.

3. The polymerizable compound (C) comprises a monofunctional and / or bifunctional monomer (C1) having a viscosity of 10 mPa·s or less at 25°C. The ultraviolet-curable inkjet composition according to claim 1, wherein the content of monofunctional and bifunctional monomers (C1) is 70% by mass or more and 100% by mass or less in the polymerizable compound (C).

4. The ultraviolet-curable inkjet composition according to claim 1, wherein the colorant (A) further comprises at least one selected from a red pigment, a purple pigment, and a black pigment.

5. The ultraviolet-curable inkjet composition according to claim 1, wherein the polymerization initiator (D) comprises an acylphosphine compound and / or an oxime ester compound.

6. A cured film formed by an ultraviolet-curable inkjet composition according to any one of claims 1 to 5.

7. A color filter having a substrate and the cured film described in claim 6.

8. A solid-state image sensor comprising the color filter described in claim 7.

9. An image display device comprising the color filter described in claim 7.

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