Coloring liquid, coloring liquid set, recording medium, and coloring method

Abstract

Provided is a colored liquid comprising: a colorant having a naphthalene skeleton in the molecule; a compound having two or more naphthalene skeletons in the molecule (which is neither the colorant having a naphthalene skeleton in the molecule nor a compound having a pyrazine skeleton in the molecule) and / or a compound having a pyrazine skeleton in the molecule (which is not the colorant having a naphthalene skeleton in the molecule); and water. Also provided are a colored-liquid set including the colored liquid, a recording medium on which the colored liquid or the colored liquids of the set have been deposited, and a coloring method in which the colored liquid or the colored-liquid set is used.

Description

[Technical Field]

[0001] The present invention relates to a coloring liquid, a coloring liquid set including the coloring liquid, a recording medium to which the coloring liquid or each coloring liquid included in the coloring liquid set is attached, and a coloring method using the coloring liquid or the coloring liquid set. [Background technology]

[0002] Many dyes and pigments have been developed to date, some of which have been assigned color index numbers and are commercially available. Taking azo dyes as an example, azo dyes synthesized by diazo coupling have been known for a long time and are widely used industrially, particularly for printing books and coloring various products essential to modern life, such as clothing, food, furniture, and building materials. In recent years, they have also been increasingly used in a wide range of fields, such as inks for inkjet printing (see, for example, Patent Document 1).

[0003] On the other hand, when used in precision electronic devices such as inkjet printers, there are several important issues that must be overcome, such as ensuring the re-solubility of the coloring liquid when it dries. Various methods have been researched to solve these issues, but it was not previously known that the addition of specific compounds can improve the performance of the coloring liquid, and even the performance of the colored recording media. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-185201 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention aims to provide a coloring liquid that can give a colored product that has excellent resolubility when dried and excellent fastness, a coloring liquid set that includes the coloring liquid, a recording medium to which the coloring liquid or each coloring liquid included in the coloring liquid set is attached, and a coloring method that uses the coloring liquid or coloring liquid set. [Means for solving the problem]

[0006] Specific means for solving the above problems include the following embodiments. 1) A coloring liquid containing at least one compound selected from the group consisting of a dye having a naphthalene skeleton in the molecule, a compound having two or more naphthalene skeletons in the molecule (excluding the dye having a naphthalene skeleton in the molecule and the compound having a pyrazine skeleton in the molecule), and a compound having a pyrazine skeleton in the molecule (excluding the dye having a naphthalene skeleton in the molecule).

[0007] 2) 1) The colored liquid according to 1), wherein the compound having two or more naphthalene skeletons in the molecule is a compound having a hydroxyl group in the molecule.

[0008] 3) The colored liquid according to 1) or 2), wherein the compound having two or more naphthalene skeletons in the molecule is a compound having a binaphthalene skeleton having a substituent.

[0009] 4) The colored liquid according to any one of 1) to 3), wherein the compound having two or more naphthalene skeletons in the molecule is 1,1'-binaphthalene-2,2'-diol.

[0010] 5) The colored liquid according to any one of 1) to 4), wherein the compound having a pyrazine skeleton in the molecule is a compound represented by the following formula (1): [ka] (In formula (1), the ring Ar 1 and ring Ar2 R each independently represents a benzene ring or a naphthalene ring. 1 and R 2 is the ring Ar 1 R 3 and R 4 is the ring Ar 2 R 1 , R 2 , R 3 , and R 4 each independently represents a hydrogen atom, a hydroxyl group, a carboxy group, a halogeno group, an alkyl group, a phenyl group, a phenoxy group, a naphthyl group, a hydroxynaphthyl group, a naphthoxy group, an amino group, a nitro group, a sulfo group, a sulfamoyl group, an acetyl group, an acetamido group, a methylamino group, an ethylamino group, a cyano group, a methoxycarbonyl group, an ethoxycarbonyl group, a 3-methoxy-2-hydroxypropylamino group, a phenylamino group, a methoxyamino group, a hydroxyethylamino group, a hydroxypropylamino group, an N-acetyl-N-methylamino group, or an acetoxyethoxyethylamino group.

[0011] 6) The colored liquid according to any one of items 1) to 5), wherein the compound having a pyrazine skeleton in the molecule is a compound represented by the following formula (1-1): [ka]

[0012] 7) The colored liquid according to any one of 1) to 6), wherein the dye having a naphthalene skeleton in the molecule is an azo dye having an azo bond in the molecule.

[0013] 8) The colored liquid according to any one of items 1) to 7), wherein the dye having a naphthalene skeleton in the molecule is an azo metal complex dye.

[0014] 9) 8) The coloring liquid according to 8), wherein the azo metal complex dye is an azo metal complex dye containing a metal selected from the group consisting of chromium, copper, iron, and cobalt.

[0015] 10) The coloring liquid according to any one of 1) to 9), wherein the content of the compound having two or more naphthalene skeletons in the molecule is less than 1.8 parts by mass when the content of the colorant having a naphthalene skeleton in the molecule is 100 parts by mass.

[0016] 11) The coloring liquid according to any one of 1) to 10), wherein the content of the compound having a pyrazine skeleton in the molecule is less than 1.2 parts by mass when the content of the colorant having a naphthalene skeleton in the molecule is 100 parts by mass.

[0017] 12) the dye having a naphthalene skeleton in the molecule is at least one dye selected from the group consisting of CI Acid Brown 298; CI Acid Blue 193; and CI Acid Black 52, 52:1, 172, and 194; the compound having two or more naphthalene skeletons in the molecule is 1,1'-binaphthalene-2,2'-diol, The colored liquid according to any one of items 1) to 11), wherein the compound having a pyrazine skeleton in the molecule is a compound represented by the following formula (1-1): [ka]

[0018] 13) The colored liquid according to any one of 1) to 12), which contains both the compound having two or more naphthalene skeletons in the molecule and the compound having a pyrazine skeleton in the molecule.

[0019] 14) The coloring liquid according to any one of items 1) to 13), further containing a water-soluble organic solvent.

[0020] 15) A coloring liquid set comprising the coloring liquid according to any one of 1) to 14) above and at least one coloring liquid having a hue different from that of the coloring liquid.

[0021] 16) A recording medium to which the coloring liquid according to any one of 1) to 14) or each of the coloring liquids included in the coloring liquid set according to 15) is attached.

[0022] 17) 16) The recording medium according to 16), wherein the recording medium is a fiber.

[0023] 18) A coloring method for coloring a recording medium by applying the coloring liquid according to any one of 1) to 14) or each of the coloring liquids included in the coloring liquid set according to 15) to the recording medium. [Effects of the Invention]

[0024] According to the present invention, it is possible to provide a coloring liquid that can give a colored product that has excellent resolubility when dried and excellent fastness, a coloring liquid set that includes the coloring liquid, a recording medium to which the coloring liquid or each coloring liquid included in the coloring liquid set is attached, and a coloring method that uses the coloring liquid or coloring liquid set. DETAILED DESCRIPTION OF THE INVENTION

[0025] Specific embodiments of the present invention will be described in detail below. In this specification, "CI" stands for Color Index.

[0026] <Colored liquid> The coloring liquid according to this embodiment contains at least one compound selected from the group consisting of a dye having a naphthalene skeleton in the molecule, a compound having two or more naphthalene skeletons in the molecule (excluding the dye having a naphthalene skeleton in the molecule and the compound having a pyrazine skeleton in the molecule), and a compound having a pyrazine skeleton in the molecule (excluding the dye having a naphthalene skeleton in the molecule). The coloring liquid according to this embodiment contains water.

[0027] As described above, by incorporating a compound having two or more naphthalene skeletons in its molecule and / or a compound having a pyrazine skeleton in its molecule in addition to a dye having a naphthalene skeleton in its molecule, the performance of the colored liquid and the performance of the colored recording medium tend to be improved. The reason for this is not entirely clear, but the present inventors speculate as follows.

[0028] That is, the compound having two or more naphthalene skeletons in its molecule and the compound having a pyrazine skeleton in its molecule contribute to the solubility and dissolution stability of the dye having a naphthalene skeleton in its molecule, which is thought to improve the filterability of the colored liquid, suppress filter clogging, and prevent unintended precipitation of the dye due to factors such as drying. Furthermore, for the above reasons, it is thought that it will also be easier to redissolve a dried colored liquid. These improved performances are thought to effectively prevent clogging of head filters and nozzles when the colored liquid is used as ink for inkjet printers, for example, and improve the ejection stability of the ink.

[0029] Furthermore, when a compound having two or more naphthalene skeletons in the molecule and / or a compound having a pyrazine skeleton in the molecule is contained, ultraviolet rays and oxidizing gases act preferentially on these compounds, which is thought to improve the fastness of the colored recording medium. For example, if the recording medium is cloth, lightfastness tends to improve, and if the recording medium is paper such as photo paper, lightfastness and ozone fastness tend to improve.

[0030] Each component contained in the colored liquid according to this embodiment will be described in detail below. Note that each component described below may be used alone or in combination of two or more.

[0031] [Dyes with a naphthalene skeleton in the molecule] A colorant having a naphthalene skeleton in the molecule (hereinafter also referred to as a "naphthalene skeleton-containing colorant") may be either a dye or a pigment. Examples of the dye include direct dyes, acid dyes, reactive dyes, disperse dyes (sublimation dyes, solvent dyes, etc.), cationic dyes, azoic dyes, sulfur dyes, and mordant dyes. Among these dyes, disperse dyes, cationic dyes, direct dyes, acid dyes, and reactive dyes are preferred.

[0032] Examples of dyes containing a naphthalene skeleton include azo dyes having an azo bond in the molecule, azine dyes, azomethine dyes, aminoketone dyes, xanthene dyes, quinoline dyes, nitro dyes, methine dyes, stilbene dyes, styryl dyes, naphthalocyanine dyes, oxazole dyes, formazan dyes, anthraquinone dyes, phthalocyanine dyes, coumarin dyes, triphenylmethane dyes, etc. Among these, azo dyes are preferred.

[0033] When the naphthalene skeleton-containing dye is an azo dye, it may be made into an azo metal complex dye by incorporating a metal into the molecule.

[0034] The metal in the azo metal complex dye is not particularly limited as long as it is a metal that can form a complex with the azo dye, but is preferably a metal selected from the group consisting of chromium, copper, iron, and cobalt.

[0035] Examples of azo dyes or azo metal complex dyes include CI Acid Yellow 33 and 100; CI Acid Orange 7, 8, 9, 12, 16, 17, 19, 20, 23, 27, 30, 31, 41, 51, 55, 56, 127, 137, 159, and 160; and CI Acid Red 4, 6, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 25, and 25:1, 27, 30, 31, 32, 37, 42, 44, 54, 56, 57, 60, 66, 68, 70, 71, 74, 86, 88, 89, 97, 99, 102, 116, 118, 119, 127, and 133. , 134, 135, 137, 141, 142, 144, 145, 148, 151, 154, 158, 163, 173, 182, 184, 186, 231, 256, 257, 266, 276, 301, 308, 337, 355, 366, 374, 440, 442, 444; CI Acid Brown 2, 3, 4, 5, 6, 7, 8, 14, 15, 16, 17, 20, 29, 32, 43, 44, 45, 46, 64, 86, 87, 88, 90, 91, 102, 105, 122, 146, 214, 282, 283, 294, 295, 296, 297, 298, 454, 469, 471; CI Acid Violet 1, 2, 14, 27, 56, 62, 67, 78, 90, 91, 117, 119; CI Acid Blue 36, 44, 70, 85, 92, 113, 116, 118, 120, 135, 155, 158, 158:1, 161, 171, 193, 194, 229, 234, 300, 328, 349; CI Acid Green 12, 19, 34, 35, 45, 73, 74, 75, 76, 77, 122, 125; CI Acid Black 3, 4, 5, 7, 16, 17, 18, 20, 21, 23, 24, 26, 16:1, 26:2, 27, 31, 32, 34, 35, 36, 43, 51, 52, 52:1, 63, 64, 107, 109, 112, 124, 155, 172, 194, 234; CI Reactive Yellow 16; CI Reactive Orange 1, 4, 5, 7, 13, 16, 17, 18, 20, 35, 44, 56, 64, 72, 78, 84, 95, 97, 124; CIReactive Red 5, 7, 8, 9, 11, 13, 16, 22, 33, 43, 46, 55, 59, 65, 66, 84, 123, 136, 158, 159, 174, 180, 183, 186, 196, 206, 222, 224, 230, 236; CI Reactive Brown 1, 2, 7, 8, 9, 10, 17, 23, 33, 43, 45, 47; CI Reactive Violet 9; CI Reactive Blue 39, 40, 82, 112, 243; CI Reactive Black 1, 3, 9, 13; CI Mordant Brown 33; CI Mordant Black 7, 17; Kayacel Red CB Liquid, Kayacel Black CN Liquid, Kayacelon React Brown CN-AM; CI Direct Yellow 52, ​​87; CI Direct Orange 26, 29, 29:1, 102, 104, 108, 118; CI Direct Red 1, 2, 4, 6, 7, 8, 10, 13, 14, 15, 16, 17, 22, 23, 24, 26, 28, 29, 31, 32, 33, 34, 36, 42, 44, 45, 50, 52, 53, 54, 55, 57, 59, 60, 61, 62, 64, 65, 83:1, 88, 89, 90, 95, 99, 117, 118, 119, 120, 122, 123, 126, 127; 127:1, 130, 141, 142, 144, 145, 147, 148, 149, 150, 152, 153, 154, 155, 168, 169, 173, 174, 175, 181, 186, 189, 191, 194, 212, 224, 225, 226, 227, 239, 242, 243, 250, 254, 257, 258, 264; CI Direct Brown 2, 13, 14, 24, 25, 26, 46, 50, 56, 57, 58, 59, 60, 61, 63, 67, 68, 69, 70, 73, 74, 75, 86, 95, 99, 101,112,149,151,166,167,168,171,179,186,190,202,206,208,209,210,223,224;CIDirect Violet 1, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 17, 21, 22, 25, 26, 27, 28, 31, 32, 35, 36, 37, 38, 39, 40, 41, 42, 43, 46, 47, 48, 51, 53, 56, 57, 62, 63, 64, 66, 72, 77, 78, 79, 80, 81, 83, 85, 87, 100, 102, 103; CI Direct Blue 2, 3, 4, 8, 9, 12, 16, 19, 21, 22, 23, 26, 27, 29, 30, 31, 33, 34, 35, 36, 38, 39, 42, 43, 45, 48, 49, 50, 51, 54, 55, 58, 60, 63, 64, 65, 67, 69, 70, 71, 72, 74, 75, 78, 81, 82, 83, 90, 93, 96, 98, 110, 111, 116, 120, 121, 122, 123, 124, 126, 127, 128, 129, 110, 131, 132, 133, 135, 136, 138, 140, 145, 148, 149, 150, 151, 152, 157, 158, 159, 162, 163, 164, 165, 166, 167, 168, 175, 176, 177, 183, 184, 185, 186, 200, 201, 203, 214, 215, 230, 231, 237, 239, 248, 258, 270, 273, 274, 278, 288, 289, 291, 295, 306, 308; CI Direct Green 3, 11, 13, 19, 20, 21, 22, 23, 33, 34, 36, 38, 39, 42, 443, 49, 50, 51, 57, 64; CI Direct Black 1, 2, 3, 9:1, 10, 14, 15, 17, 22, 24, 27, 29, 32, 36, 40, 48, 49, 51, 56, 71, 74, 75, 76, 77, 78, 80, 87, 91, 96, 97, 100, 101, 103, 112, 117, 118, 122, 131, 132, 141, 150, 151, 153, 156, 164, 173, 196, 197, 198, 199; Kayacelon Red C-HB, Kayacelon Rubin C-BL, Kayafect Red S Liquid, Kayafect Red H Liquid 50, Kayaku Direct Fast Red S Liquid 10BX;CI Disperse Yellow 97;CIExamples include Disperse Orange 13, 42, and 125; CI Disperse Red 6, 44, 81, 141, 151, 200, 220, 271, 330, and 334; CI Disperse Blue 15, 38, 85, 194, 260, 283, and 294; CI Disperse Black 1; CI Basic Yellow 41; CI Basic Orange 47; CI Sulphur Green 6; and CI Sulphur Black 6 and 11. Among these, those containing a naphthol skeleton within the molecule are preferred, with CI Acid Brown 298, CI Acid Blue 193, and CI Acid Black 52, 52:1, 172, and 194 being more preferred, and CI Acid Brown 298, CI Acid Blue 193, and CI Acid Black 172 being even more preferred.

[0036] The content of the naphthalene skeleton-containing dye is typically 0.5 to 25% by mass, preferably 1 to 20% by mass, and more preferably 1 to 17% by mass, relative to the total mass of the colored liquid. When the colored liquid according to this embodiment is used as a light-colored colored liquid or ink (so-called light ink) in which the content of the naphthalene skeleton-containing dye is set low, the content of the naphthalene skeleton-containing dye is typically 0.025 to 5% by mass, preferably 0.05 to 2.5% by mass, and more preferably 0.05 to 2% by mass, relative to the total mass of the colored liquid.

[0037] [Compounds with two or more naphthalene structures in the molecule] The compound having two or more naphthalene skeletons in the molecule (hereinafter also referred to as "naphthalene-based compound") is not particularly limited as long as it does not include the above-mentioned naphthalene skeleton-containing dyes and compounds having a pyrazine skeleton in the molecule and has two or more naphthalene skeletons in the molecule.

[0038] Among naphthalene compounds, compounds having a hydroxyl group in the molecule and compounds having a binaphthalene skeleton in the molecule are preferred, compounds having a substituted binaphthalene skeleton in the molecule are more preferred, compounds having both a hydroxyl group and a binaphthalene skeleton in the molecule are even more preferred, and 1,1'-binaphthalene-2,2'-diol is particularly preferred. 1,1'-binaphthalene-2,2'-diol may be in any of the racemic, R- or S-forms.

[0039] The content of the naphthalene compound is preferably less than 1.8 parts by mass, more preferably 0.0001 part by mass or more and less than 1.8 parts by mass, even more preferably 0.0002 part by mass or more and less than 1.5 parts by mass, particularly preferably 0.0005 to 1.0 part by mass, and extremely preferably 0.001 to 1.0 part by mass, when the content of the naphthalene skeleton-containing dye is 100 parts by mass.

[0040] [Compounds with a pyrazine skeleton] The compound having a pyrazine skeleton in the molecule (hereinafter also referred to as "pyrazine-based compound") is not particularly limited as long as it does not contain the above-mentioned naphthalene skeleton-containing dye and has a pyrazine skeleton in the molecule.

[0041] Among pyrazine compounds, the compound represented by the following formula (1) is preferred.

[0042] [ka]

[0043] In the above formula (1), the ring Ar 1 and ring Ar 2 R each independently represents a benzene ring or a naphthalene ring. 1 and R 2 is the ring Ar 1 R 3 and R 4 is the ring Ar 2 R 1 , R2 , R 3 , and R 4 each independently represents a hydrogen atom, a hydroxyl group, a carboxy group, a halogeno group, an alkyl group, a phenyl group, a phenoxy group, a naphthyl group, a hydroxynaphthyl group, a naphthoxy group, an amino group, a nitro group, a sulfo group, a sulfamoyl group, an acetyl group, an acetamido group, a methylamino group, an ethylamino group, a cyano group, a methoxycarbonyl group, an ethoxycarbonyl group, a 3-methoxy-2-hydroxypropylamino group, a phenylamino group, a methoxyamino group, a hydroxyethylamino group, a hydroxypropylamino group, an N-acetyl-N-methylamino group, or an acetoxyethoxyethylamino group.

[0044] Examples of the halogeno group include a fluorine group, a chlorine group, a bromine group, and an iodine group.

[0045] Examples of the alkyl group include linear or branched alkyl groups having 1 to 20 carbon atoms. Specific examples of the alkyl group include, but are not limited to, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group.

[0046] Ring Ar 1 and ring Ar 2 When represents a naphthalene ring, the naphthalene ring can be bonded to the pyrazine ring at any position. For example, the ring Ar 1 and ring Ar 2 When each of the groups represents a naphthalene ring, the structures represented by the following formulae (A) to (D) can be adopted.

[0047] [ka]

[0048] Among the compounds represented by the above formula (1), particularly preferred compounds include compounds represented by the following formula (1-1).

[0049] [ka]

[0050] The compound represented by the formula (1) is a type of azine dye, well known as CI Acid Black 2, and has been widely used for dyeing textiles. There are various types of azine dyes, including those with phenazine and naphthazine rings, and they can be obtained, for example, based on the non-patent literature [Hiroshi Horiguchi (1969). Review of Synthetic Dyes, Sankyo Publishing].

[0051] The compound of formula (1-1) can also be obtained by, for example, brominating the commercially available compound of formula (D) and then reacting the boronated 2-naphthol by Suzuki-Miyaura cross-coupling reaction.

[0052] The content of the pyrazine compound is preferably less than 1.2 parts by mass, more preferably 0.0001 part by mass or more and less than 1.2 parts by mass, even more preferably 0.0002 to 1.0 part by mass, particularly preferably 0.0005 to 0.5 parts by mass, and extremely preferably 0.001 to 0.5 parts by mass, when the content of the naphthalene skeleton-containing dye is taken as 100.

[0053] The coloring liquid according to this embodiment preferably contains both a naphthalene-based compound and a pyrazine-based compound, and more preferably contains both 1,1'-binaphthalene-2,2'-diol and the compound represented by the above formula (1-1).

[0054] [water] As the water, ion-exchanged water, distilled water, or the like containing few impurities is preferred.

[0055] The content of water is preferably 1 to 99% by mass, and more preferably 5 to 95% by mass, relative to the total mass of the colored liquid.

[0056] [Water-soluble organic solvent] The coloring liquid according to this embodiment may further contain a water-soluble organic solvent. Examples of the water-soluble organic solvent include alcohols, pyrrolidones, and polyoxyalkylene diglyceryl ethers. Examples of the alcohols include C2-C6 alcohols having 2 to 3 hydroxy groups, such as glycerin, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,3-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 2,4-diethyl-1,5-pentanediol, 3-methyl-1,3-butanediol, and 3-methyl-1,5-pentanediol; and polyglyceryl alcohols, such as diglycerin and polyglycerin. ethers; polyoxy C2-C3 alkylene polyglyceryl ethers such as polyoxyethylene polyglyceryl ether and polyoxypropylene polyglyceryl ether; mono-, di-, or tri-C2-C3 alkylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, and polyethylene glycol; poly C2 alkylene glycols with a repeating unit number of 4 or more and a molecular weight of about 20,000 or less, such as polyethylene glycol and polypropylene glycol; -C3 alkylene glycol (preferably liquid); C1-C6 monoalkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether (butyl carbitol), triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether (butyl triglycol), propylene glycol monomethyl ether, propylene glycol monoethyl ether (1-ethoxy-2-propanol), dipropylene glycol monopropyl ether (1-(1-methyl-2-propoxyethoxy)-2-propanol), dipropylene glycol monobutyl ether (1-(2-butoxy-1-methylethoxy)propan-2-ol), diethylene glycol monoethyl ether, and diethylene glycol monohexyl ether (hexyl carbitol);Examples of suitable polyols include C1-C6 dialkyl ethers of polyhydric alcohols such as diethylene glycol diethyl ether (diethyl carbitol); glycol monoethers such as 3-methoxy-1-butanol and 3-methoxy-3-methylbutanol; and glycol phenyl ethers such as propylene glycol (mono)phenyl ether (1-phenoxy-2-propanol). Examples of pyrrolidones include 2-pyrrolidone, N-methyl-2-pyrrolidone, and 1-(2-hydroxyethyl)-2-pyrrolidone. Examples of suitable polyoxyalkylene diglyceryl ethers include polyoxypropylene diglyceryl ethers such as SC-P400, SC-P750, SC-P1000, SC-P1200, and SC-P1600, all of which are manufactured by Sakamoto Pharmaceutical Co., Ltd.; and polyoxyethylene diglyceryl ethers such as SC-E450, SC-E750, SC-E1000, SC-E1500, and SC-E2000. Among these, glycerin, diglycerin, 1,3-propanediol, 1,5-pentanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 1,2-hexanediol, ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, diethylene glycol monobutyl ether, 1,3-butanediol, 1,6-hexanediol, triethylene glycol, triethylene glycol monobutyl ether, 1-(2-hydroxyethyl)-2-pyrrolidone, and 2-pyrrolidone are preferred;

[0057] The content of the water-soluble organic solvent is usually 0 to 50% by mass, preferably 1 to 50% by mass, and more preferably 5 to 40% by mass, relative to the total mass of the colored liquid.

[0058] [Additives] The coloring liquid according to this embodiment may further contain other additives, such as surfactants, pH adjusters, antiseptics and fungicides, dye dissolving agents, hydrotropic agents, and moisturizing agents.

[0059] The total content of the additives is usually 0 to 10% by mass, and preferably about 0.05 to 5% by mass, relative to the total mass of the colored liquid.

[0060] The surfactant may be anionic, cationic, amphoteric, or nonionic surfactants, with nonionic surfactants being preferred.

[0061] Examples of anionic surfactants include alkyl sulfocarboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acylamino acids or salts thereof, N-acylmethyl taurines, alkyl sulfates, polyoxyalkyl ether sulfates, alkyl sulfates, polyoxyethylene alkyl ether phosphates, rosin acid soaps, castor oil sulfates, lauryl alcohol sulfates, alkylphenol phosphates, alkyl phosphates, alkylaryl sulfonates, diethyl sulfosuccinates, diethylhexyl sulfosuccinates, and dioctyl sulfosuccinates.

[0062] Examples of cationic surfactants include 2-vinylpyridine derivatives and poly(4-vinylpyridine) derivatives.

[0063] Examples of amphoteric surfactants include lauryl dimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethyl imidazolinium betaine, coconut oil fatty acid amidopropyl dimethylaminoacetic acid betaine, polyoctyl polyaminoethyl glycine, and imidazoline derivatives.

[0064] Examples of nonionic surfactants include ether surfactants such as polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene dodecylphenyl ether, polyoxyethylene oleyl ether, polyoxyethylene lauryl ether, and polyoxyethylene alkyl ether; polyoxyethylene oleate, polyoxyethylene distearate, sorbitan laurate, sorbitan monostearate, sorbitan monooleate, and sorbitan sesquioleate. ester-based surfactants such as 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, and 3,5-dimethyl-1-hexyn-3-ol; and Surfynol 104E, 104H, 104A, 104PA, 104PG50, DF110D, 82, 420, 440, 465, 485, and Olfine STG, both of which are trade names, manufactured by Nissin Chemical Industry Co., Ltd. Among these, Surfynol is preferred, and Surfynol 104PG50, DF110D, 420, 440, and 465 are more preferred.

[0065] When the colored liquid according to this embodiment contains a surfactant, the content thereof is usually 0.001 to 2% by mass, and preferably 0.01 to 1.5% by mass, relative to the total mass of the colored liquid.

[0066] Any substance can be used as the pH adjuster as long as it can control the pH of the coloring liquid within the range of 6.0 to 11.0. Examples of pH adjusters include alkanolamines such as diethanolamine, dimethylethanolamine, diethylethanolamine, and triethanolamine; alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; ammonium hydroxide (aqueous ammonia); alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate; and tris(hydroxymethyl)aminomethane. Of these, triethanolamine is preferred.

[0067] When the colored liquid according to this embodiment contains a pH adjuster, the content thereof is usually 0.01 to 2% by mass, and preferably 0.05 to 1% by mass, relative to the total mass of the colored liquid.

[0068] Examples of antiseptic and antifungal agents include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, zinc pyridinethione-1-oxide, 1,2-benzisothiazolin-3-one, amine salts of 1-benzisothiazolin-3-one, Biox P520LP and Preventol BIT 20N manufactured by LANXESS, ROCIMA 640 manufactured by Dow Chemical Company, Mergal K-20 manufactured by TROY, and Proxel GXL and Proxel XL2 manufactured by Lonza. Of these, Proxel GXL and Proxel XL2 are preferred.

[0069] When the coloring liquid according to this embodiment contains an antiseptic / antifungal agent, the content thereof is usually 0.001 to 2% by mass, and preferably 0.01 to 1% by mass, relative to the total mass of the coloring liquid.

[0070] Examples of dye dissolving agents include urea, ε-caprolactam, and ethylene carbonate.

[0071] Examples of hydrotropic agents include urea, thiourea, cyanoguanidine, guanidine phosphate, and guanidine sulfamate.

[0072] Examples of moisturizing agents include urea and glycerin.

[0073] [Preparation method of coloring solution] The colored liquid according to this embodiment can be obtained by dissolving a naphthalene skeleton-containing dye, a naphthalene-based compound, a pyrazine-based compound, and, if necessary, other additives in a solvent such as water.

[0074] The naphthalene skeleton-containing dyes, naphthalene compounds, and pyrazine compounds may be commercially available or synthesized. Naphthalene compounds and pyrazine compounds can be obtained, for example, by separating and purifying by-products produced during the synthesis of the naphthalene skeleton-containing dyes. Commonly known methods for purifying dyes and chemical substances can be used for the separation and purification. Specific separation and purification methods include, for example, the recrystallization method, sublimation method, dialysis method, salting out method, ion exchange resin method, column chromatography method, thin layer chromatography method, and paper chromatography method described in the non-patent document [Journal of the Society of Organic Synthetic Chemistry, Vol. 13, No. 4, p. 106, 1955], as well as methods using adsorbents, ultrafiltration method, reverse osmosis membrane method, and distillation method.

[0075] Examples of ion exchange resins include cation exchange resins and anion exchange resins. Examples of adsorbents include activated carbon, zeolite, diatomaceous earth, cellulose fiber, chelating fiber, and synthetic adsorbents. In the ion exchange resin method or the adsorbent method, a dye solution prepared by dissolving or dispersing a dye in water or an appropriate organic solvent may be mixed with an ion exchange resin or an adsorbent, stirred, and then filtered. Alternatively, a dye solution prepared by dissolving or dispersing a dye in water or an appropriate organic solvent may be passed through a column packed with an ion exchange resin or an adsorbent.

[0076] Naphthalene compounds and pyrazine compounds can be detected or quantified by general analytical methods for measuring organic compounds, such as nuclear magnetic resonance analysis, high performance liquid chromatography, high performance liquid chromatography / mass spectrometry, paper chromatography, thin layer chromatography, gas chromatography, gas chromatography / mass spectrometry, gel permeation chromatography, elemental analysis, infrared spectroscopy, and infrared-visible spectroscopy.

[0077] [Uses of coloring liquid] The colored liquid according to this embodiment can be used for various recording purposes such as printing, copying, marking, writing, drafting, stamping, etc., but is particularly suitable for inkjet recording. When the colored liquid according to this embodiment is used as an ink for inkjet recording, the colored liquid according to this embodiment may be used as is, or other additives may be further added as necessary.

[0078] When the colored liquid according to this embodiment is used as an ink for inkjet recording, it is preferable to carry out precision filtration using a membrane filter, etc. The pore size of the membrane filter is usually 0.1 to 1 μm, and preferably 0.1 to 0.5 μm.

[0079] Furthermore, when the colored liquid according to this embodiment is used as an inkjet recording ink, the viscosity of the colored liquid at 25°C is preferably 3 to 20 mPa·s when measured using an E-type viscometer. Furthermore, the surface tension of the colored liquid at 25°C is preferably 20 to 45 mN / m when measured using a plate method. The viscosity and surface tension of the colored liquid are preferably adjusted to appropriate values ​​within the above ranges, taking into consideration the inkjet printer's discharge rate, response speed, droplet flight characteristics, inkjet head characteristics, and the like.

[0080] <Coloring liquid set> The coloring liquid set according to this embodiment includes the coloring liquid according to this embodiment and at least one coloring liquid having a hue different from that of the coloring liquid. Examples of the coloring liquid that may be included in the coloring liquid set according to this embodiment include a magenta coloring liquid, a cyan coloring liquid, a yellow coloring liquid, a blue coloring liquid, a green coloring liquid, an orange coloring liquid, a gray coloring liquid, and a black coloring liquid.

[0081] <Recording media and coloring method> The recording medium according to this embodiment is one to which the coloring liquid according to this embodiment or each coloring liquid included in the coloring liquid set according to this embodiment is adhered, and the coloring method according to this embodiment involves adhering the coloring liquid according to this embodiment or each coloring liquid included in the coloring liquid set according to this embodiment to the recording medium to color it.

[0082] Examples of recording media include information transmission sheets such as plain paper, resin-coated paper, inkjet paper, glossy paper, glossy film, and paper for common use in electrophotography; fibers (cotton, linen, nylon, wool, silk, etc.), fabrics; glass; metals; ceramics; leather; color filter substrates; etc. Sheet-shaped recording media are preferably used, but recording media having a three-dimensional shape other than a sheet, such as a spherical shape or a rectangular parallelepiped shape, may also be used.

[0083] The method for applying the colored liquid to the recording medium is not particularly limited, and a preferred example is an inkjet recording method.

[0084] Preferred recording media for inkjet recording include, for example, those in which an ink-receiving layer is provided on a substrate such as paper, synthetic paper, or film. The ink-receiving layer can be provided by, for example, impregnating or coating the substrate with a cationic polymer; or by coating the substrate surface with inorganic fine particles capable of absorbing the dye in the coloring liquid, such as porous silica, alumina sol, or special ceramics, together with a hydrophilic polymer such as polyvinyl alcohol or polyvinylpyrrolidone. Recording media provided with such an ink-receiving layer are usually referred to as inkjet paper (film), glossy paper (film), or the like. Among these, inkjet paper, in which inorganic fine particles capable of absorbing the dye in the coloring liquid, such as porous silica, alumina sol, or special ceramics, are coated on the substrate surface, is considered to be susceptible to oxidizing gases in the air, such as ozone gas. Representative examples of commercially available specialty paper include Canon Inc.'s Photo Paper Glossy Pro "Platinum Grade" and Photo Paper Glossy Gold; Seiko Epson Corp.'s Crispia Photo Paper (High Gloss), Photo Paper (Glossy), and Photo Matte Paper; Hewlett-Packard Japan Ltd.'s Advanced Photo Paper (Glossy); and Brother Corp.'s Premium Plus Glossy Photo Paper. Plain paper can also be used, including Canon Inc.'s PB Paper GF500, Seiko Epson Corp.'s Double-Sided High-Quality Plain Paper, and PPC (Plain Paper Copy) paper.

[0085] Furthermore, preferred recording media used in inkjet recording include fibers. Examples of fibers that are preferably used include polyamide fibers, blended fibers containing polyamide fibers, cellulose fibers, and blended fibers containing cellulose fibers. Examples of polyamide fibers include silk, wool, and nylon. Examples of cellulose fibers include cotton, linen, rayon, and polynosic. Examples of blended fibers include blends of polyamide fibers or cellulose fibers with other fibers. The fibers also include fiber structures (such as fabrics).

[0086] <Textile dyeing method> The method for dyeing fibers according to this embodiment uses the coloring liquid according to this embodiment as an ink and includes sequentially carrying out at least the following steps.

[0087] [Process A] The process of applying ink to textiles using methods such as inkjet printing, screen printing, dip dyeing, or continuous dyeing. [Process B] This is the process of fixing the ink pigments that have been applied to the fibers to the fibers. [Process C] This is the process of washing away any unfixed dye remaining on the fibers.

[0088] Inkjet printers that can be used in step A include, for example, those that use a piezo method that utilizes mechanical vibrations; and those that use a bubble jet (registered trademark) method that utilizes bubbles generated by heating.

[0089] In step B, the ink-coated fibers are pre-dried at room temperature to 130°C for 0.5 to 30 minutes, and then steamed to fix the dye to the fibers under moist heat conditions. The steaming treatment is preferably carried out in an environment with a relative humidity of 80 to 100% and a temperature of 95 to 105°C for 5 to 30 minutes.

[0090] In step C, it is preferable to wash the fiber after fixing the dye with water. In this washing, washing may be performed with water containing a surfactant. After carrying out step C, the washed fiber is usually dried at 40 to 120°C for 5 to 30 minutes to obtain a dried dyed product.

[0091] [Pretreatment process] For the purpose of preventing bleeding of the dye, a step of pretreating the fibers may be further included before the step A. When printing polyamide fibers or cellulose fibers, it is preferable to include a pretreatment step.

[0092] The pretreatment step may include applying an aqueous solution containing a paste material and a pH adjuster as a fiber pretreatment liquid to the fibers before carrying out step A. The pretreatment liquid preferably further contains a hydrotropic agent.

[0093] Examples of adhesives contained in the pretreatment liquid include natural gums such as guar and locust bean; starches; seaweeds such as sodium alginate and funori; plant skins such as pectic acid; cellulose derivatives such as methylcellulose, ethylcellulose, hydroxyethylcellulose, and carboxymethylcellulose; processed starches such as carboxymethyl starch; processed natural gums such as shirat gum and roasted bean gum; and synthetic glues such as polyvinyl alcohol and polyacrylic esters. Of these, natural gums such as guar and locust bean; processed natural gums such as shirat gum and roasted bean gum are preferred.

[0094] Examples of pH adjusters contained in the pretreatment solution include alkaline sodium salts such as sodium carbonate and sodium bicarbonate; and acidic ammonium salts such as ammonium sulfate, ammonium tartrate, and ammonium acetate.

[0095] Examples of hydrotropic agents contained in the pretreatment liquid include urea, dimethylurea, thiourea, monomethylthiourea, dimethylthiourea, etc. Of these, urea is preferred.

[0096] The content of each component in the pretreatment liquid varies depending on the blending ratio of the blended fibers, for example, when blended fibers are used, making it difficult to determine a general value. A rough guideline is that the content of the sizing agent is 0.5 to 5 mass%, the content of the pH adjuster is 0.5 to 5 mass%, and the remainder is water, relative to the total mass of the pretreatment liquid. When the pretreatment liquid further contains a hydrotropic agent, the content of the hydrotropic agent is preferably 1 to 20 mass%, relative to the total mass of the pretreatment liquid. The pretreatment liquid is preferably acidic, and its pH range is usually pH 7 or less, preferably pH 5 to 7.

[0097] The method of applying the pretreatment liquid to the fibers includes, for example, padding, in which the squeezing rate is preferably about 40 to 90%, more preferably about 60 to 80%.

[0098] [Post-processing process] If necessary, the dyed product may be subjected to post-treatment using a fixing agent, an ultraviolet absorber, an antioxidant, etc., for the purpose of improving light fastness, wet fastness, and chlorine fastness.

[0099] Examples of fixing agents used in post-treatment include polyamine-based, polycation-based, tannin-based, and synthetic tannin-based fixing agents.

[0100] Examples of ultraviolet absorbers used in post-treatment include benzophenone compounds, benzotriazole compounds, cinnamic acid compounds, triazine compounds, stilbene compounds, etc. Compounds that absorb ultraviolet light and emit fluorescence, such as benzoxazole compounds, can also be used.

[0101] Examples of antioxidants used in post-treatment include L-ascorbic acid (also known as vitamin C), erythorbic acid, and α-tocopherol (also known as vitamin E).

[0102] For all of the above-mentioned items, a combination of preferred items is more preferred, and a combination of more preferred items is even more preferred. The same applies to a combination of a preferred item with a more preferred item, a combination of a more preferred item with an even more preferred item, etc. [Example]

[0103] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Note that the inks in each example are all included in the coloring liquid.

[0104] <Examples 1 to 10 and Comparative Examples 1 to 3: Preparation of Coloring Liquid> Commercially available CI Acid Blue 193, CI Acid Black 172, and CI Acid Brown 298 were purified by activated carbon filtration, microfiltration, and ultrafiltration. The purified CI Acid Blue 193, CI Acid Black 172, or CI Acid Brown 298 was mixed with 1,1'-binaphthalene-2,2'-diol (a naphthalene-based compound), the compound represented by formula (1-1) above (a pyrazine-based compound), and water to obtain the compositions shown in Tables 1 to 3 below, thereby obtaining colored solutions of Examples 1 to 10 and Comparative Examples 1 to 3. In Tables 1 to 3, the numerical values ​​for each component represent parts by mass.

[0105] [Table 1]

[0106] [Table 2]

[0107] [Table 3]

[0108] <Evaluation> The following evaluation tests were carried out using each of the coloring solutions prepared as described above. The results are shown in Tables 4 and 5. All of the coloring solutions of Examples 1 to 10 had good filterability when the entire solution was filtered using a mixed cellulose filter (manufactured by Advantec Co., Ltd.) with a diameter of 47 mm and a pore size of 0.2 μm, and were unlikely to leave any foreign matter or coloring on the filter.

[0109] [Evaluation of drought resistance] One part by mass of each coloring liquid was dropped onto a glass petri dish with an outer diameter of 32 mm (FINE petri dish, manufactured by Tokyo Glass Instruments Co., Ltd.), and then left to stand in a dryer at 30°C. Observations were made at regular intervals and the drying resistance was evaluated according to the following criteria. A drying resistance rating of "D" indicates lack of practical use. -Evaluation criteria- A: After 6 hours, the coloring liquid on the dish is not dry (it is fluid). B: The colored liquid on the dish has not dried after 4 hours (it is fluid). C: After 2 hours, the colored liquid on the dish is not dry (it is fluid). D: After 1 hour, the colored liquid on the dish is not dry (it is fluid).

[0110] [Evaluation of resolubility] 0.5 parts by mass of each coloring liquid was dropped onto a glass petri dish with an outer diameter of 32 mm (Tokyo Glass Instruments Co., Ltd., FINE Petri dish), and after air drying, 0.5 parts of water was dropped onto it, and the resolubility was evaluated according to the following criteria. A resolubility rating of "D" indicates lack of practical use. -Evaluation criteria- A: Redissolves within 5 minutes. B: More than 5 minutes and redissolves within 10 minutes. C: Redissolves in more than 10 minutes and within 30 minutes. D: Remains undissolved even after 30 minutes and cannot be redissolved.

[0111] "Resolubility" is considered to be an indicator of whether nozzle function can be restored by re-dissolving or re-dispersing the ink by supplying new ink, etc., when the solids concentration increases due to the evaporation of volatile components in the ink, causing the dissolved or dispersed components to become unstable and aggregate or precipitate, clogging the nozzle, etc. (See Journal of the Imaging Society of Japan, Vol. 41, No. 2 (2002), p. 182). If the ink cannot be re-dissolved when it dries, this means that the nozzle function cannot be restored, and such ink is not suitable for practical use.

[0112] [Table 4]

[0113] [Table 5]

[0114] As shown in Tables 4 and 5, the colored solutions of Examples 1 to 10, which contained a naphthalene compound and / or a pyrazine compound, all had practical drying resistance and resolubility. In addition, the colored solutions of Examples 1 to 10 also had good filterability.

[0115] <Examples 11 to 26 and Comparative Examples 4 to 6: Preparation of Inks> Inks of Examples 11 to 26 and Comparative Examples 4 to 6 were obtained by mixing the components listed in Tables 6 to 9 below. In Tables 6 to 9, the numerical values ​​for each component represent parts by mass. In addition, the abbreviations in Tables 6 to 9 represent the following: TEG: Triethylene glycol (Mitsubishi Chemical Corporation) TEGMBE: Triethylene glycol monobutyl ether (Kanto Chemical Co., Ltd.) Surfynol 465: surfactant (manufactured by Nissin Chemical Industry Co., Ltd.) Proxel XL2: Antiseptic and antifungal agent (manufactured by Lonza) TEA: Triethanolamine (Mitsui Chemicals, Inc.) 2Py: 2-pyrrolidone (Mitsubishi Chemical Corporation) Gly: Glycerin (Junsei Chemical Co., Ltd.)

[0116] [Table 6]

[0117] [Table 7]

[0118] [Table 8]

[0119] [Table 9]

[0120] <Evaluation> Using each of the inks prepared as described above, evaluation tests for drying resistance and resolubility were conducted in the same manner as in Example 1. Furthermore, the following evaluation tests were conducted using each ink. The results are shown in Tables 10 to 12 below. All of the inks of Examples 11 to 26 exhibited good filterability when the entire ink was filtered through a mixed cellulose filter (manufactured by Advantec Co., Ltd.) with a diameter of 47 mm and a pore size of 0.2 μm, and were also less likely to leave foreign matter or coloring on the filter. Furthermore, when a nozzle check pattern was printed using the inks of Examples 11 to 26 using an inkjet printer PX-205 (manufactured by Seiko Epson Corporation), there was little loss of print, and good prints could be obtained.

[0121] [Evaluation of lightfastness of dyed fabric] A pretreatment solution containing guar (2 parts by mass), ammonium sulfate (2 parts by mass), urea (5 parts by mass), and water (91 parts by mass) was prepared, and silk fabric (silk habutae) was pretreated using the pad method. Specifically, the silk fabric was immersed in the pretreatment solution, excess liquid was squeezed off with a rubber roller, and then dried at 60°C. A container filled with each ink was loaded into a PX-205 inkjet printer (manufactured by Seiko Epson Corporation), and a solid pattern was inkjet printed on the pretreated silk fabric at 100% gradation to obtain each printed fabric. Each printed fabric was then pre-dried at 60-80°C and steamed for 30 minutes under conditions of 90% or higher relative humidity and 100-103°C. The resulting printed fabric was washed in cold water for 5 minutes and then dried to obtain each test dyed fabric.

[0122] Each test fabric was subjected to a lightfastness test according to JIS L0843 Method A. Specifically, a xenon weather meter SUGA NX75 (manufactured by Suga Test Instruments Co., Ltd.) was used to irradiate each test fabric with light for 39.4 hours. The irradiation conditions were: black panel temperature: 63°C, chamber temperature: 38°C, relative humidity: 50%, and irradiance: 50 W / m 2The test conditions were: wavelength 300-400 nm, inner filter: quartz, outer filter: soda lime glass. The color of each test fabric was measured before and after the test using a colorimeter (SectroEye, manufactured by GretagMacbeth), and the color difference (ΔE) was calculated according to the following formula (1). In formula (1), ΔL*, Δa*, and Δb* represent the differences in L*, a*, and b* before and after the test, respectively. ΔE=[(ΔL*) 2 +(Δa*) 2 +(Δb*) 2 ] 1 / 2 ···(1) Then, the lightfastness was evaluated based on the calculated color difference (ΔE) value according to the following criteria. -Evaluation criteria- A: ΔE is less than 1.2 B: ΔE is 1.2 or more and less than 1.6 C: ΔE is 1.6 or more and less than 1.9 D: ΔE is 1.9 or more

[0123] [Evaluation of lightfastness and ozone resistance of photo paper] The containers filled with each ink were loaded into an inkjet printer PX-205 (manufactured by Seiko Epson Corporation), and solid printing was performed on photographic paper (manufactured by Seiko Epson Corporation) to obtain a recorded matter. The obtained recorded matter was used as a test piece and subjected to a light fastness test and an ozone fastness test.

[0124] For the light resistance test, a Xenon Weatherometer XL75 (manufactured by Suga Test Instruments Co., Ltd.) was used, and each test piece was irradiated with light for 50 hours. The irradiation conditions were: chamber temperature: 24°C, relative humidity: 60%, irradiance: 0.36 W / m 2 The reflection density before and after the test was measured using a colorimeter (SectroEye, manufactured by GretagMacbeth) within a reflection density (Dc or Dk) range of 0.70 to 0.85, and the dye residual rate was calculated according to the following formula (2). Dye remaining rate = (reflection density after test / reflection density before test) × 100 (%) (2) Then, the light resistance was evaluated based on the calculated dye remaining rate according to the following criteria. -Evaluation criteria- A: Pigment retention rate is 90% or more B: Pigment remaining rate is 80% or more but less than 90% C: Pigment remaining rate is 70% or more but less than 80% D: Pigment remaining rate is less than 70%

[0125] For the ozone resistance test, an ozone weather meter OMS-H (manufactured by Suga Test Instruments Co., Ltd.) was used, and each test piece was left for 16 hours under conditions of an ozone concentration of 1 ppm, a temperature inside the chamber of 23°C, and a relative humidity of 50%. Then, the remaining pigment on each test piece was visually confirmed, and the ozone resistance was evaluated according to the following criteria. -Evaluation criteria- a: The original pigment remains clearly visible. b: A small amount of the original pigment remains. c: The original pigment cannot be seen.

[0126] [Table 10]

[0127] [Table 11]

[0128] [Table 12]

[0129] As shown in Tables 10 to 12, the inks of Examples 11 to 26, which contain naphthalene-based compounds and / or pyrazine-based compounds, all possess practical drying resistance and resolubility, and are believed to be excellent at preventing and recovering from printer head nozzle clogging. The inks of Examples 11 to 26 also exhibited good filterability and ink ejection properties. Furthermore, recording media (silk cloth, photo paper) colored with the inks of Examples 11 to 26 exhibited improved lightfastness and ozone resistance. Furthermore, when 6,6-nylon was dyed instead of silk cloth (silk habutae), the resulting dyed fabric also exhibited good lightfastness.

Claims

1. A coloring liquid containing a dye having a naphthalene skeleton in the molecule, at least one compound selected from the group consisting of a compound having two or more naphthalene skeletons in the molecule and a compound having a pyrazine skeleton in the molecule, and water, The dye having a naphthalene skeleton in the molecule is at least one dye selected from the group consisting of C.I. Acid Brown 298; C.I. Acid Blue 193; and C.I. Acid Black 52, C.I. Acid Black 52:1, C.I. Acid Black 172, and C.I. Acid Black 194; the compound having two or more naphthalene skeletons in the molecule is 1,1'-binaphthalene-2,2'-diol, The compound having a pyrazine skeleton in the molecule is represented by the following formula (1-1): 【Chemistry 2】 is a compound represented by when the content of the dye having a naphthalene skeleton in the molecule is taken as 100 parts by mass, the content of the compound having two or more naphthalene skeletons in the molecule is 0 parts by mass or more and less than 1.8 parts by mass, the content of the compound having a pyrazine skeleton in the molecule is 0 parts by mass or more and less than 1.2 parts by mass when the content of the dye having a naphthalene skeleton in the molecule is 100 parts by mass.

2. 2. The colored liquid according to claim 1, comprising both the compound having two or more naphthalene skeletons in the molecule and the compound having a pyrazine skeleton in the molecule.

3. The coloring liquid according to claim 1 or 2, further comprising a water-soluble organic solvent.

4. A coloring liquid set comprising the coloring liquid according to any one of claims 1 and 2 and at least one coloring liquid having a hue different from that of the coloring liquid.

5. A recording medium to which the coloring liquid according to any one of claims 1 to 3 or each of the coloring liquids included in the coloring liquid set according to claim 4 is attached.

6. The recording medium of claim 5 , wherein the recording medium is a fiber.

7. A coloring method for coloring a recording medium by applying the coloring liquid according to any one of claims 1 to 3 or each of the coloring liquids included in the coloring liquid set according to claim 4 to the recording medium.

Images