Coloring liquid

Abstract

To provide a coloring liquid and a coloring liquid set including the same, a colored recording medium and a coloring method.SOLUTION: A coloring liquid comprises a compound represented by the formula (1), and (1,4-Bis-(2-bromo-4-butyl-O-toluidino) anthraquinone. (In the formula (1), M denotes a monovalent cation).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a coloring solution, a coloring solution set using the same, a colored recording medium, and a coloring method. [Background technology]

[0002] Many dyes and pigments have been developed, and some have been commercialized with color index numbers. For example, anthraquinone dyes have been known for a long time and are widely used, including being synthesized industrially. They are used in various products essential to modern life, such as book printing, clothing, food coloring, furniture, and building materials. In recent years, their use has been expanding to a wide range of fields, including inkjet printing inks and functional dyes. On the other hand, when used in precision electronic devices such as inkjet printers, there are several important challenges that must be overcome, such as ensuring the filterability and storage stability of the coloring solution. Various methods have been researched to solve these problems, but it was previously unknown that adding a specific compound could improve the performance of the coloring solution and, furthermore, the performance of the printed material. [Overview of the Initiative] [Problems that the invention aims to solve]

[0003] This invention was made to solve the above problems, and aims to provide a coloring liquid and ink with excellent resolubility, and printed materials with excellent durability. [Means for solving the problem]

[0004] As a result of diligent research, the inventors of the present invention have found that a coloring solution containing the compound represented by the following formula (1) and the compound represented by the following formula (2) can solve the aforementioned problems, and have completed the present invention.

[0005] [ka] (In equation (1), M represents a monovalent cation.)

[0006] [ka]

[0007] More specifically, by including the compound represented by formula (1) and the compound represented by formula (2) above, the solubility and stability of the compound represented by formula (1) are improved. As a result, the filterability of the colored solution is improved, preventing filter clogging, preventing the unintended precipitation of specific dyes due to factors such as drying, and making it easier to redissolve a colored solution that has dried out. These performance improvements effectively prevent clogging of the head filter and nozzles when the colored solution is used as ink in an inkjet printer, thus improving the stability of ink ejection.

[0008] Furthermore, it is also effective in improving durability; for example, if the colored material is fabric, it can improve sweat fastness and wash fastness, and if it is paper, including photographic paper, it can improve water resistance and ozone resistance.

[0009] In other words, the present invention relates to the following 1) to 7). 1) A coloring solution containing a compound represented by the following formula (1) and a compound represented by the following formula (2).

[0010] [ka] (In equation (1), M represents a monovalent cation.)

[0011] [ka]

[0012] 2) The coloring solution described in 1), wherein the coloring solution is a dye solution or an ink. 3) The coloring liquid according to any one of 1) or 2) further containing a water-soluble organic solvent. 4) A coloring liquid set containing the coloring liquid according to any one of 1) to 3). 5) A recording medium colored with either the coloring liquid according to any one of 1) to 3) or the coloring liquid set according to 4). 6) The recording medium according to 5), wherein the recording medium is a fiber. 7) A coloring method for performing coloring with either the coloring liquid according to any one of 1) to 3) or the coloring liquid set according to 4).

Advantages of the Invention

[0013] According to the present invention, a coloring liquid and an ink excellent in redissolution property can be provided, and a printed matter excellent in fastness can be provided.

Modes for Carrying Out the Invention

[0014] Hereinafter, the present invention will be described in detail. In this specification, unless otherwise specified, "parts" and "%" are both based on mass including examples and the like. Also, C.I. represents an abbreviation of Color Index.

[0015] The coloring liquid in the present invention is characterized by containing the compound represented by the above formula (1) and the compound represented by the following formula (2).

[0016] Examples of the compound represented by the above formula (1) include C.I. Acid Blue 140, and the C.I. Acid Blue 140 can be produced by a method known in the literature or an application thereof, or a commercially available product may be used.

[0017] In the above formula (1), M represents hydrogen, an alkali metal ion, an alkaline earth metal ion, an onium ion of an organic amine or an ammonium ion. In formula (1) above, when M is an alkali metal ion, an alkaline earth metal ion, an onium ion of an organic amine, or an ammonium ion, the compound represented by formula (1) above is a salt of an inorganic or organic cation. Specific examples of inorganic salts include alkali metal salts, alkaline earth metal salts, or ammonium salts, with preferred inorganic salts being salts of lithium, sodium, potassium, or ammonium. Examples of salts of the organic cations include, but are not limited to, the quaternary ammonium ion shown in formula (3) below. Furthermore, free acids, their tautomers, and various salts thereof may be mixtures. For example, a mixture of sodium salt and ammonium salt, a mixture of free acid and sodium salt, a mixture of lithium salt, sodium salt, and ammonium salt, etc., can be used in any combination. Depending on the type of salt, physical properties such as solubility may differ, and the type of salt can be appropriately selected, or if multiple salts are included, their ratios can be changed, etc., to suit the purpose.

[0018] [ka]

[0019] In general formula (3), Z 1 , Z 2 , Z 3 , Z 4 Each of these independently represents a group selected from the group consisting of a hydrogen atom, an alkyl group, a hydroxyalkyl group, and a hydroxyalkoxyalkyl group. Z in general formula (3) 1 , Z 2 , Z 3 , Z 4Specific examples of the alkyl group include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, etc. Specific examples of the hydroxyalkyl group include, for example, hydroxymethyl group, hydroxyethyl group, 3-hydroxypropyl group, 2-hydroxypropyl group, 4-hydroxybutyl group, 3-hydroxybutyl group, 2-hydroxybutyl group and other hydroxy C1-C4 alkyl groups. Examples of the hydroxyalkoxyalkyl group include, for example, hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group, 3-hydroxyethoxypropyl group, 2-hydroxyethoxypropyl group, 4-hydroxyethoxybutyl group, 3-hydroxyethoxybutyl group, 2-hydroxyethoxybutyl group and other hydroxy C1-C4 alkoxy C1-C4 alkyl groups. Among these, hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group and other hydroxyethoxy C1-C4 alkyls are preferred. Z in the general formula (3) 1 Z 2 Z 3 Z 4 As, particularly preferred ones include hydrogen atom; methyl group, hydroxymethyl group, hydroxyethyl group, 3-hydroxypropyl group, 2-hydroxypropyl group, 4-hydroxybutyl group, 3-hydroxybutyl group, 2-hydroxybutyl group and other hydroxy C1-C4 alkyl groups, hydroxyethoxymethyl group, 2-hydroxyethoxyethyl group, 3-hydroxyethoxypropyl group, 2-hydroxyethoxypropyl group, 4-hydroxyethoxybutyl group, 3-hydroxyethoxybutyl group, 2-hydroxyethoxybutyl group and other hydroxyethoxy C1-C4 alkyl groups.

[0020] Z of the preferred compound as the general formula (3) 1 Z 2 Z 3 And Z 4 Specific examples of the combination are shown in Table 1 below.

[0021]

Table 1

[0022] To obtain a salt of the compound represented by formula (1) above, for example, after the reaction, salting out can be performed by adding the desired inorganic salt or organic cation salt to the reaction solution, or by isolating it in the form of a free acid by adding a mineral acid such as hydrochloric acid, removing the inorganic salt by washing with water, acidic water, or an aqueous organic medium as needed, and then neutralizing it with the desired inorganic or organic base in an aqueous medium to obtain a solution of the corresponding salt. Here, acidic water refers to water that has been made acidic by dissolving mineral acids such as sulfuric acid and hydrochloric acid, or organic acids such as acetic acid, in water. The aqueous organic medium refers to organic substances that contain water and are miscible with water, as well as so-called organic solvents that are miscible with water. Specific examples include water-soluble organic solvents, which will be described later, but even organic substances that are not normally classified as solvents can be used as needed if they are miscible with water. Examples of organic substances that are not normally classified as solvents include urea and sugars. Examples of inorganic salts include alkali metal salts such as lithium chloride, sodium chloride, and potassium chloride, and ammonium salts such as ammonium chloride and ammonium bromide. Examples of organic cation salts include halogen salts of organic amines. Examples of inorganic bases include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide, ammonium hydroxide, or alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate. Examples of organic bases include, but are not limited to, organic amines, such as diethanolamine and triethanolamine, which are quaternary ammonium compounds represented by the aforementioned general formula (3). The countercation preferably forms a salt with the cations of an inorganic metal, ammonia (NH3), or an organic base.

[0023] The compound represented by formula (2) above can be obtained as the product 1,4-Bis-(2-bromo-4-butyl-O-toluidino)anthraquinone (manufactured by Alfa Chemistry, USA), 1,4-Bis((2-Bromo-4-Butyl-6-Methylphenyl)Amino)Anthracene-9,10-Dione (manufactured by Chemieliva Pharmaceutical, China), and 1,4-bis(2-bromo-4-butyl-6-methylanilino)anthracene-9,10-dione (manufactured by Atomax Chemicals, China).

[0024] In the above coloring solution, when the content of the compound represented by formula (1) is 100 parts, the content of the compound represented by formula (2) is preferably 0.00001 parts or more and less than 2.0 parts, more preferably 0.00002 parts or more and less than 1.5 parts, even more preferably 0.00005 parts or more and 1.0 part or less, particularly preferably 0.01 parts or more and 0.5 parts or less, and extremely preferably 0.02 parts or more and 0.15 parts or less.

[0025] The above-mentioned coloring solution can be used not only for forming monochrome images but also for forming full-color images. To form full-color images, for example, the above-mentioned coloring solution can be used as a cyan coloring solution and combined with magenta and yellow coloring solutions to form a set of three primary colors, or even a set of four coloring solutions by adding black coloring solution. Furthermore, to form higher-resolution images, for example, the above-mentioned coloring solution can be used as a blue coloring solution and combined with magenta, light magenta, red, green, orange, dark yellow, gray, etc., to form a set of coloring solutions. It is particularly preferable to use the above-mentioned coloring solution as a blue or cyan coloring solution. The above-mentioned coloring solution can also be used as a blue or cyan coloring solution and combined with other coloring solutions. For example, the above-mentioned coloring solution can be used as a blue coloring solution and combined with cyan coloring solution, or the above-mentioned coloring solution can be used as a cyan coloring solution and combined with blue coloring solution. Examples of pigments included in the coloring solution to be used in conjunction with the above-mentioned coloring solution include known yellow pigments, known magenta pigments, known cyan pigments, known black pigments, and so on.

[0026] Examples of the known yellow dyes mentioned above include azo dyes having aryl and / or heteroaryl; methine dyes such as benzylidene dye and monomethine oxonol dye; quinone dyes such as naphthoquinone dye and anthraquinone dye; quinophthalone dyes; nitro / nitroso dyes; acridine dyes; acridinone dyes; and the like.

[0027] Examples of the known magenta dyes mentioned above include azo dyes having aryl and / or heteroaryl; azomethine dyes; methine dyes such as arylidene, styryl, merocyanine, cyanine, and oxonol; carbonium dyes such as diphenylmethane, triphenylmethane, and xanthene; quinone dyes such as naphthoquinone, anthraquinone, and anthrapyridone; and condensed polycyclic dyes such as dioxazine.

[0028] Examples of the known cyanide dyes mentioned above include phthalocyanine dyes, naphthalocyanine dyes, azo dyes having aryl and / or heteroaryl; azomethine dyes; methine dyes such as allylidene dyes, styryl dyes, merocyanine dyes, cyanine dyes, and oxonol dyes; carbonium dyes such as diphenylmethane dyes, triphenylmethane dyes, and xanthene dyes; quinone dyes such as naphthoquinone, anthraquinone, and anthrapyridone; and condensed polycyclic dyes such as dioxazine dyes.

[0029] Examples of the known black dyes mentioned above include metal-containing azo compounds, azo dyes such as disazo, trisazo, or tetraazo; sulfur dyes; carbon black dispersions; and the like.

[0030] When the above-mentioned coloring solution is used as a blue coloring solution or a cyan coloring solution, the other coloring solutions (hereinafter sometimes abbreviated as "other coloring solutions") may be dyes having a structure other than CI Acid Blue 140, which can be arbitrarily selected and used.

[0031] The above coloring solution may be used by arbitrarily selecting and mixing any of the above-mentioned pigments, in addition to the compound represented by formula (1) and the compound represented by formula (2), to create a suitable color. Furthermore, any other coloring solution that can be combined with the above coloring solution may also be used by arbitrarily selecting and mixing any of the above-mentioned pigments to create a suitable color.

[0032] In this specification, "coloring solution" refers to a solution used for various recording purposes such as dyeing (printing, immersion dyeing), copying, marking, writing, drafting, and stamping, and is particularly suitable as a dye solution for dyeing textiles or as an ink for use in inkjet printers. The above-mentioned coloring solution may also be used as the dye solution or the ink.

[0033] The above coloring solution may further contain a water-soluble organic solvent.

[0034] The above-mentioned water-soluble organic solvents are not particularly limited, but examples include alcohols, pyrrolidones, and polyoxyalkylene diglyceryl ethers. The content of these solvents in the above-mentioned coloring solution is usually 0 to 50%, preferably 1 to 50%, and more preferably 5 to 40%, relative to the total mass of the coloring solution. Examples of alcohols include C2-C6 alcohols having 2 to 3 hydroxyl 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, 3-methyl-1,3-butanediol, and 2,4-diethyl-1,5-pentanediol; polyglyceryl ethers such as diglycerin and polyglycerin; and polyoxyethylene polyglyceryl ethers. Polyoxy C2-C3 alkylene polyglyceryl ethers such as 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-C3 alkylene glycols such as polyethylene glycol and polypropylene glycol, having 4 or more repeating units and a molecular weight of approximately 20,000 or less (preferably liquid);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 Examples include C1-C6 monoalkyl ethers of polyhydric alcohols such as monobutyl ether (1-(2-butoxy-1-methylethoxy)propan-2-ol), diethylene glycol monoethyl ether, and diethylene glycol hexyl ether (diethylene glycol monohexyl ether, hexyl carbitol); 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 polyoxyalkylene diglyceryl ethers include polyoxypropylene diglyceryl ethers such as SC-P400, SC-P750, SC-P1000, SC-P1200, and SC-P1600, all 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, 2,4-diethyl-1,5-pentanediol, 1,2-hexanediol, ethylene glycol, propylene 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. Water-soluble organic solvents can be used alone or in combination.

[0035] The above coloring solution may also contain other additives.

[0036] Other additives mentioned above may include, for example, surfactants, pH adjusters, preservatives and fungicides, hydrotropic agents, humectants, dye solvents, etc., as needed.

[0037] Examples of surfactants include anionic, cationic, amphoteric, and nonionic surfactants. Among these, cationic surfactants are preferred. Examples of anionic surfactants include alkyl sulfocarboxylates, α-olefin sulfonates, polyoxyethylene alkyl ether acetates, N-acyl amino acids or their salts, N-acyl methyl taurates, alkyl sulfates, polyoxyalkyl ether sulfates, alkyl sulfates, polyoxyethylene alkyl ether phosphates, rosinic acid soaps, castor oil sulfates, lauryl alcohol sulfates, alkylphenol type phosphates, alkyl type phosphates, alkylaryl sulfonates, diethyl sulfosaturates, diethylhexyl sulfosaturates, and dioctyl sulfosaturates. Examples of cationic surfactants include 2-vinylpyridine derivatives and poly-4-vinylpyridine derivatives. Examples of amphoteric surfactants include lauryldimethylaminoacetic acid betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, coconut oil fatty acid amidopropyl dimethylaminoacetic acid betaine, polyoctyl polyaminoethylglycine, and imidazoline derivatives. Examples of nonionic surfactants include ether-based 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. Esters such as polyoxyethylene monooleate and polyoxyethylene stearate; acetylene alcohols such as 2,4,7,9-tetramethyl-5-decine-4,7-diol, 3,6-dimethyl-4-octin-3,6-diol, and 3,5-dimethyl-1-hexyn-3-ol; other specific examples include, for instance, the trade names Surfinol 104E, 104H, 104A, 104PA, 104PG50, DF110D, 82, 420, 440, 465, 485, and Olfin STG, manufactured by Nisshin Chemical Co., Ltd.Among these, Surfinol is preferred, and Surfinol 104PG50, DF110D, 420, 440, and 465 are more preferred.

[0038] Any substance that can control the pH of the ink to a range of 6.0 to 11.0 can be used as a pH adjuster. Examples include alkanolamines such as diethanolamine, dimethylethanolamine, diethylethanolamine, and triethanolamine; alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; ammonium hydroxide (ammonia water); or alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate; tris(hydroxymethyl)aminomethane; and so on. Among these, triethanolamine is preferred. The content of the pH adjuster in the total mass of the ink is usually 0.01 to 2%, preferably 0.05 to 1%.

[0039] Examples of preservatives and fungicides include sodium dehydroacetate, sodium benzoate, sodium pyridinethion-1-oxide, zinc pyridinethion-1-oxide, 1,2-benzisothiazolin-3-one, amine salts of 1-benzisothiazolin-3-one, Lanxess Biox P520LP, Preventol BIT 20N, Dow Chemical's ROCIMA 640, Troy's Mergal K-20, Lonza's Proxel GXL, and preferably Proxel GXL, Proxel XL2, etc.

[0040] Examples of dye dissolving agents include urea, ε-caprolactam, and ethylene carbonate.

[0041] Examples of hydrotropic agents include urea, thiourea, cyanoguanidine, guanidine phosphate, and guanidine sulfamate.

[0042] Examples of moisturizers include urea and glycerin.

[0043] The method for preparing the above-mentioned coloring solution is described below. The compound represented by formula (1) and the compound represented by formula (2) above can be obtained by purchase or synthesis. Furthermore, to adjust the proportions of the compound represented by formula (1) and the compound represented by formula (2) in the colored solution, for example, the compound represented by formula (1) and the compound represented by formula (2) can be blended in any proportion, or the blending ratio of a mixture containing the compound represented by formula (1) and the compound represented by formula (2) can be adjusted by the purification method described later. As for the purification method, for example, generally known methods for purifying dyes or chemical substances can be used. Specific purification methods include, for example, the recrystallization method, sublimation method, dialysis method, salting-out method, ion exchange resin method, column chromatography or thin-layer chromatography or paper chromatography method described in non-patent literature (Journal of the Society of Synthetic Organic Chemistry, 1955, Vol. 13, No. 4, p. 106), as well as methods using adsorbents, ultrafiltration method, reverse osmosis membrane method, distillation method, etc. Examples of ion exchange resins include cation exchange resins and anion exchange resins. Examples of adsorbents include activated carbon, zeolite, diatomaceous earth, cellulose particles, cellulose fibers, chelate fibers, and synthetic adsorbents. In the ion exchange resin method and the adsorbent method, the ion exchange resin or adsorbent may be mixed with a dye solution prepared by dissolving or dispersing the dye in water, a suitable organic solvent, or ink, and then the mixture may be filtered or passed through a column packed with the ion exchange resin or adsorbent. By performing the methods listed herein, either individually or in combination, the compound represented by formula (1) and the compound represented by formula (2) can be prepared, respectively. However, the present invention is not limited to the purification methods exemplified herein.

[0044] Methods for detecting and quantifying the compound represented by formula (1) and the compound represented by formula (2) above can be the general analytical methods used to measure organic compounds, such as nuclear magnetic resonance spectroscopy, 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.

[0045] The above-mentioned colored solution can be obtained by dissolving the compound represented by formula (1) and the compound represented by formula (2) prepared above in a solvent such as water.

[0046] A set of coloring solutions containing multiple of the above-mentioned coloring solutions, and a set of coloring solutions containing the above-mentioned coloring solutions and coloring solutions other than the above-mentioned coloring solutions are also included in the present invention.

[0047] Recording media colored with either the above-mentioned coloring liquid or the above-mentioned coloring liquid set are also included in the present invention.

[0048] Of the recording media mentioned above, there are no particular limitations on those used for inkjet recording, but surface-treated materials, specifically those with an ink-receiving layer on a substrate such as paper, synthetic paper, or film, or fibers are preferred. The ink-receiving layer can be provided, for example, by impregnating or coating the substrate with a cationic polymer; or by coating the substrate surface with inorganic fine particles capable of absorbing pigments in ink, such as porous silica, alumina sol, or special ceramics, together with a hydrophilic polymer such as polyvinyl alcohol or polyvinylpyrrolidone. Recording media with such an ink-receiving layer are usually called inkjet-specific paper (film), glossy paper (film), etc. Among these, inkjet-specific paper of the type in which inorganic fine particles capable of absorbing pigments in ink, such as porous silica, alumina sol, or special ceramics, are coated on the substrate surface is considered to be particularly susceptible to oxidizing gases in the air, such as ozone gas. Typical examples of the aforementioned specialized papers available commercially include Canon Inc.'s "Photo Paper Glossy Pro Platinum Grade" and "Photo Paper Glossy Gold"; Seiko Epson Corporation's "Photo Paper Crispia (High Gloss)," "Photo Paper (Glossy)," and "Photo Matte Paper"; Hewlett-Packard Japan's "Advanced Photo Paper (Glossy)"; and Brother Corporation's "Premium Plus Glossy Photo Paper." Of course, plain paper can also be used, specifically Canon Inc.'s "PB Paper GF500" and Seiko Epson Corporation's "Double-Sided Premium Plain Paper" and "PPC (Plain Paper Copy) Paper," but the applications of the ink composition of the present invention are not limited to these. The recording media described above can preferably be a sheet-like material such as fiber, resin (plastic) film, or paper, but other three-dimensional shapes such as spheres or rectangular prisms may also be used. It is particularly preferable that the recording medium is made of fiber. From the viewpoint of fully exhibiting the effects of the present invention, polyamide fibers, blended fibers containing polyamide fibers, cellulose fibers, blended fibers containing cellulose fibers, etc., are preferably used as the type of fiber. Examples of cellulose fibers include cotton, linen, rayon, and polynosic. Examples of polyamide fibers include silk, wool, and nylon. Examples of blended fibers include those that contain at least these polyamide fibers or cellulose fibers and are blended with other fibers. The above fibers also include fiber structures, and fabrics made of the above fibers are preferably mentioned.

[0049] A coloring method using either the above-mentioned coloring liquid or the above-mentioned coloring liquid set is also included in the present invention.

[0050] The above-mentioned coloring solution, or a solution of the above-mentioned coloring solution with any additives added, may be used as the ink. The above-mentioned ink is obtained by mixing the above-mentioned components to form a solution and filtering the resulting solution using a membrane filter or the like, if necessary. For inkjet printing ink, it is preferable to filter the solution using a membrane filter or the like. The pore size of the membrane filter is usually 0.1 μm to 1 μm, preferably 0.1 μm to 0.5 μm.

[0051] The viscosity of the above ink at 25°C is preferably within the range of 3 to 20 mPa·s when measured with an E-type viscometer, and the surface tension is preferably within the range of 20 to 45 mN / m when measured by the plate method. The viscosity and surface tension of the ink can be adjusted to appropriate values ​​within the above ranges, taking into consideration the printer's ejection volume, response speed, ink droplet flight characteristics, and inkjet head characteristics, etc.

[0052] The above coloring method is a method for coloring fibers, i.e., a printing method, which involves using the above coloring liquid as an ink and sequentially performing at least three steps A to C below. [Process A] A process of applying ink to fibers using a method selected from inkjet printing, screen printing, immersion dyeing, and continuous dyeing. [Process B] This step involves fixing the ink pigment, which was attached to the fibers in step A, to the fibers. [Process C] A process for washing away any remaining unfixed pigments from the fibers.

[0053] Furthermore, in addition to the three steps A to C described above, a step of pre-treating the fibers for purposes such as preventing dye bleeding may be included before step A. When printing polyamide fibers or cellulose fibers, it is preferable to include a pre-treatment step.

[0054] The fibers mentioned above are preferred examples of fibers used in the above-described printing method.

[0055] Examples of inkjet printers that can be used in the above-mentioned process A include those using a piezo method that utilizes mechanical vibration; a bubble jet (registered trademark) method that utilizes bubbles generated by heating; and others.

[0056] Step B described above includes a method in which the ink-coated fibers are left at room temperature to 130°C for 0.5 to 30 minutes to pre-dry them, and then subjected to a steaming treatment to fix the dye to the fibers under humid heat conditions. For the steaming treatment, it is preferable to leave the fibers in an environment with a humidity of 80 to 100% and a temperature of 95 to 105°C for 5 to 30 minutes.

[0057] In step C described above, it is preferable to wash the fibers with water after the dye has been fixed. For this washing, water containing a surfactant may be used. After performing step C, the washed fibers are usually dried at 40-120°C for 5-30 minutes to obtain a dried dyed product.

[0058] The surfactants that can be used in step C above may be the same as those described in the section on other additives above.

[0059] If necessary, the dyed material may be post-treated with polyamine-based, polycation-based fixatives, tannins or synthetic tannin-based fixatives, UV absorbers, antioxidants, etc., to improve its lightfastness, wet fastness, or chlorine fastness.

[0060] Examples of UV absorbers used in the above post-treatment include benzophenone compounds, benzotriazole compounds, cinnamic acid compounds, triazine compounds, and stilbene compounds. Compounds that absorb ultraviolet light and emit fluorescence, such as benzoxazole compounds, also known as fluorescent whitening agents, can also be used.

[0061] Examples of antioxidants used in the above post-treatment include L-ascorbic acid (also known as vitamin C), erythorbic acid, and α-tocopherol (also known as vitamin E).

[0062] A pretreatment step for fibers performed before step A is a step in which an aqueous solution containing at least one type of sizing agent and a pH adjuster for pretreatment is used as a fiber treatment solution and is applied to the fibers before step A is performed. Preferably, the fiber treatment solution further contains a hydrotropic agent. The sizing agent, pH adjuster for pretreatment, and hydrotropic agent contained in the fiber treatment solution are sometimes referred to as "pretreatment agents". A padding method is one example of a method for applying the fiber treatment solution to the fibers. The padding ratio is preferably about 40-90%, and more preferably about 60-80%.

[0063] Examples of adhesives to be contained in the fiber processing solution include natural gums such as guar and locust bean; starches; sodium alginate and seaweed such as funori; plant peels such as pectinic acid; cellulose derivatives such as methylcellulose, ethylcellulose, hydroxyethylcellulose, and carboxymethylcellulose; modified starches such as carboxymethyl starch; modified natural gums such as silatsu gum and roasted bean gum; and synthetic adhesives such as polyvinyl alcohol and polyacrylic acid esters. Among these, natural gums such as guar and locust bean; and modified natural gums such as silatsu gum and roasted bean gum are preferred.

[0064] Examples of pH adjusting agents for pretreatment contained in the fiber treatment solution include alkaline sodium salts such as sodium carbonate and sodium bicarbonate, acidic ammonium salts such as ammonium sulfate, ammonium tartrate, and ammonium acetate.

[0065] Examples of hydrotropic agents contained in the fiber treatment solution include urea, dimethylurea, thiourea, monomethylthiourea, and dimethylthiourea, with urea being preferred. Each of the above pretreatment agents can be used individually or in combination of two or more, with the latter being preferred.

[0066] The amount of pretreatment agents contained in the fiber treatment solution described above is difficult to determine definitively, for example, when using blended fibers, as it depends on the blending ratio of the blended fibers. However, as a guideline, the amount of sizing agent, pH adjuster for pretreatment, and the remainder being water are all typically 0.5-5% by mass of the total mass of the fiber treatment solution. If a hydrotropic agent is also included, the amount is similarly 1-20%, with the remainder being water. Furthermore, the fiber treatment solution is preferably acidic. The pH range is usually 7 or less, preferably 5-7. [Examples]

[0067] The present invention will be described in more detail below with reference to examples, but these examples do not limit the present invention. The ink in each example is included in the above-mentioned coloring liquid.

[0068] [Example 1] Five parts of the compound represented by formula (2) above (1,4-Bis-(2-bromo-4-butyl-O-toluidino)anthraquinone, manufactured by Alfa Chemistry, USA) were added to 30 parts of concentrated sulfuric acid and heated to 140°C, stirring for 40 minutes. The resulting reaction solution was added to 50 parts of ice water, filtered through a Nutsch (MT Buchner funnel, manufactured by Sekiya Rika Co., Ltd.), and the solid remaining on the Nutsch was dried to obtain one part of the compound represented by formula (1). The obtained compound represented by formula (1) was dissolved in deionized water and purified by activated carbon filtration, microfiltration, and ultrafiltration. The compound represented by formula (1) was isolated as a solid from the purified solution. Each compound was adjusted to the composition shown in Table 2 to obtain the colored solutions of Examples 1 to 14 and Comparative Example 1. A portion of the obtained colored liquid was placed on a glass petri dish with an outer diameter of 32 mm (FINE petri dish manufactured by Tokyo Glass Instruments Co., Ltd.), and dried in a drying oven at 60°C. All of the colored liquids in Examples 1 to 14 remained fluid after drying. As described above, 0.5 parts of water were added to each colored solution in a dried petri dish, and its "resolubility" was evaluated. The results are shown in 2. Furthermore, when the colored solutions of Examples 1 to 14 were completely filtered using a mixed cellulose filter (Advantec) with a diameter of φ47 mm and a pore size of 0.2 μm, they showed good filterability, and little foreign matter or coloring remained on the filter, indicating favorable results.

[0069] The evaluation criteria are as follows. [Judgment criteria] 1-1) Resolubility A: Redissolve within 5 minutes. B: Redissolve within 10 minutes, but more than 5 minutes later. C: Redissolve within 30 minutes, but more than 10 minutes later. D: After 30 minutes, some remains undissolved and cannot be redissolved.

[0070] Table 2 shows the evaluation results for the resolubility of each coloring solution. If the "resolubility" evaluation is C or lower, it is not practical. The term "re-solubility" above refers to the ability to easily redissolve and redisperse the nozzle function by supplying new ink, even when unstable dissolved and dispersed components aggregate and precipitate due to increased solid content concentration caused by evaporation of volatile components in the ink, resulting in a phenomenon close to nozzle blockage. (See Journal of the Image Arts and Sciences of Japan, Vol. 41, No. 2 (2002), p. 182)

[0071] [Table 2]

[0072] The proportions of the compound represented by formula (1) and the compound represented by formula (2) in each colored solution were calculated using HPLC (high-performance liquid chromatography) from the peak area ratio at a wavelength of 254 nm.

[0073] From the results in Table 2 above, it can be seen that the colored liquid of the present invention possesses both filterability and resolubility.

[0074] Each of the inks shown in Table 3 below was prepared, and its resolubility as an ink was evaluated. In Table 3, each abbreviation represents the following: Surfinol 465: Surfactant (manufactured by Nisshin Chemical Industry Co., Ltd.) Proxel XL2: Anti-corrosion and anti-fungal agent (manufactured by Lonza) TEA: Triethanolamine (manufactured by Mitsui Chemicals, Inc.) PG: Propylene glycol (manufactured by Junsei Chemical Co., Ltd.) Gly: Glycerin (manufactured by Pure Chemical Co., Ltd.) [Preparation of test dyed fabric] A fiber treatment solution was prepared containing 2 parts guar, 2 parts ammonium sulfate, 5 parts urea, and 91 parts water, and a pretreatment process was performed on silk fabric 1 (silk habutae) using the pad method. Specifically, the silk fabric was immersed in the fiber treatment solution, excess liquid was squeezed off with a rubber roller, and then it was dried at 60°C. On the silk cloth 1 obtained as described above, a solid pattern was inkjet printed at 100% gradation using inks prepared with the coloring solutions of Examples 1, 5, 6, 8, 11, and 14 with an inkjet printer (product name: PX-205, manufactured by Seiko Epson Corporation) to obtain a printed material. After pre-drying this printed material at 60-80°C, it was steamed at 90% humidity or higher and 100-103°C for 30 minutes. After washing the obtained printed material with cold water for 5 minutes and drying it, test dyed cloths were obtained. These test dyed cloths are designated as Examples 15-20. Each test dyed cloth was obtained in the same manner as in Examples 15-20, except that the ink of Comparative Example 2 was used instead of the ink of Examples 15-20. [Lightfastness test of dyed fabrics] Each dyed fabric obtained as described above was subjected to a lightfastness test according to JIS L0843 Method A. Specifically, under the conditions of a black panel temperature of 63°C, a chamber temperature of 38°C, a relative humidity of 50%, an irradiance of 50 W / m2 (300-400 nm), an inner filter of quartz, and an outer filter of soda-lime glass, each dyed fabric obtained as described above was irradiated with a xenon arc light source for 39.4 hours using a xenon weather meter SUGA NX75 (manufactured by Suga Test Instruments Co., Ltd.). As a result, all examples showed good results. [Alkaline sweat test on dyed fabric] Each dyed fabric obtained as described above was subjected to an alkaline sweat test according to the JIS L0848 method (alkaline). After the test, the degree of contamination of the attached silk fabric before and after the test was determined. [Judgment criteria] Alkaline sweat test of dyed fabrics A: Level 3 or above B: Level 2 or higher, but less than Level 3 C: Below Grade 2 [Wash fastness test of dyed fabrics] Each dyed fabric obtained as described above was subjected to a wash fastness test according to the JIS L 0844 method. After the test, the silk fabric attached before and after the test was measured with a colorimeter, and the pigment retention rate and color difference (ΔE) were calculated using the following formulas (I) and (II), and evaluated on a four-point scale. Pigment retention rate = (Reflectance after test / Reflectance before test) × 100 (%) Formula (I) ΔE=[(ΔL*) 2 +(Δa*) 2 +(Δb*) 2 ] 1 / 2 Formula (II) [Judgment criteria] Wash fastness test of dyed fabrics A: ΔE less than 7.0 B: ΔE 7.0 or greater, less than 17.0 C: ΔE 17.0 or greater, less than 27.0 D:ΔE27.0 or more [Water resistance test and ozone resistance test of photographic paper] Furthermore, solid prints were made on photographic paper (manufactured by Seiko Epson Corporation), and water resistance and ozone resistance tests were conducted. Specifically, for the water resistance test, each test piece was immersed in water for one hour, then removed and allowed to air dry. After the test, each test specimen was measured with a colorimeter, and the pigment retention rate and color difference (ΔE) were calculated using the above formulas (I) and (II), and evaluated on a four-point scale. The ozone resistance test was conducted using an Ozone Weather Meter OMS-H (manufactured by Suga Test Instruments Co., Ltd.) under test conditions of ozone concentration of 1 ppm, chamber temperature of 23°C, and humidity of 50% RH. Each test specimen was left for 16 hours. After the test, each test specimen was measured with a colorimeter before and after the test, and the pigment retention rate and color difference (ΔE) were calculated using the following formulas (1) and (2), and evaluated on a four-point scale. The dyed fabrics and test specimens were color-measured using a colorimeter (SectroEye, manufactured by GretagMacbeth).

[0075] [Judgment criteria] Ozone resistance of photographic paper A: ΔE less than 2.0 B: ΔE 2.0 or greater, less than 5.0 C: ΔE 5.0 or greater, less than 8.0 D:ΔE8.0 or more Water-resistant photo paper A: ΔE less than 5.0 B: ΔE 5.0 or greater and less than 8.0 C: ΔE 8.0 or greater, less than 11.0 D:ΔE11.0 or more

[0076] [Table 3]

[0077] The inks used in Examples 15-20 produced good print quality with minimal print defects when nozzle check patterns were printed using an inkjet printer PX-205 (manufactured by Seiko Epson).

[0078] From the results in Tables 2 and 3 above, the coloring solutions of the present invention all received an A rating for resolubility, demonstrating practicality and excellent ability to prevent and restore nozzle clogging in printer heads. In addition, the present invention has a good balance of resolubility, and further improvements in lightfastness and ozone resistance were observed on glossy paper. It was also found that the filtration performance, such as filtration time and filter coloring, and ink ejection performance were good. Furthermore, in the above evaluation, even when the silk cloth 1 (silk habutae) was changed to 6,6-nylon, the dyed cloths dyed using the coloring solutions of each invention all showed good lightfastness. [Industrial applicability]

[0079] The coloring solution of the present invention can provide printed materials with excellent resolubility and fastness. In particular, it is extremely useful as an inkjet printing ink and inkjet printing ink set.

Claims

1. A coloring solution containing a compound represented by the following formula (1) and a compound represented by the following formula (2), wherein the content of the compound represented by formula (2) is 0.25 parts or more and 1 part or less when the content of the compound represented by formula (1) is 100 parts. 【Chemistry 1】 (In equation (1), M represents a monovalent cation.) 【Chemistry 2】

2. The coloring solution according to claim 1, wherein the coloring solution is a dye solution or an ink.

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

4. A coloring solution set comprising the coloring solution described in claim 1 or 2.

5. A recording medium colored with the coloring liquid described in claim 1 or 2.

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

7. A coloring method that involves coloring with the coloring liquid described in claim 1 or 2.

Images