Ink set, liquid discharge apparatus, and liquid discharge method

Abstract

To provide an ink set that prevents deterioration of the texture when printing is performed by discharging a liquid onto a fabric, obtains desirable coloring property and fastness, and has desirable preservation stability of a pretreatment liquid.SOLUTION: An ink set for fabric printing comprises a pretreatment liquid and an aqueous ink, wherein the aqueous ink comprises a pigment, the pretreatment liquid comprises an organic acid and an amino-modified silicone, the content of the amino-modified silicone in the pretreatment liquid is 1 mass% or more and less than 15 mass%, and the organic acid has a pKa at 25°C of 2.5 or more and less than 5.0, and the content of the organic acid in the pretreatment liquid is 5 mass% or more and 20 mass% or less.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an ink set, a liquid ejection apparatus, and a liquid ejection method. [Background technology]

[0002] Inkjet printing has become increasingly popular in recent years due to its ability to easily record color images and its low running costs. It is also beginning to gain popularity in the field of textile printing, which has traditionally been done using analog methods centered on dyes. In particular, the use of aqueous pigment inks, which use pigments as colorants, can significantly reduce the amount of industrial wastewater generated by textile printing. Combined with the inventory reduction achieved by on-demand printing using inkjet printing, inkjet printing is known as an environmentally friendly printing method.

[0003] In textile printing using aqueous pigment inks, color development, fastness, and texture are major issues, and companies are actively studying these issues. In addition, inkjet ink sets consisting of ink and a pretreatment liquid, which are used to deposit ink on fabric to form an image, have also been proposed.

[0004] Patent Document 1 discloses a pretreatment liquid for textile printing that is used together with inkjet ink and contains a predetermined amount of polysaccharides having amino groups. According to Patent Document 1, it is possible to suppress bleeding of images and improve wet rub fastness. Patent Document 2 discloses a textile printing treatment liquid containing two organic acids at a predetermined mass ratio, which is used so that the two come into contact with each other in a liquid state in relation to an aqueous inkjet ink composition. According to Patent Document 2, printing can be performed so that the aqueous inkjet ink composition and the textile printing treatment liquid on the treated fabric come into contact with each other in a liquid state (wet-on-wet). Patent Document 3 discloses an inkjet ink fixing composition containing a property adjusting agent, a friction coefficient reducing agent, and a carrier. Patent Document 4 discloses a textile printing ink set including a combination of a printing pretreatment agent and a water-based pigment ink, in which the pretreatment agent contains a hydrophilic silicone resin and water, and has a predetermined dynamic contact angle with the hydrophilic silicone resin surface within a predetermined range. Patent Document 4 states that even inkjet printing using a water-based pigment ink can produce printed textiles with image density comparable to that obtained by conventional screen printing. Summary of the Invention [Problem to be solved by the invention]

[0005] However, particularly with regard to texture, there is a problem that the texture of fabrics is deteriorated by printing with pigment inks. Therefore, there is a demand for a technology that can improve the color development, fastness, and texture when inkjet printing is performed on fabrics. Furthermore, when inkjet printing is performed using a pretreatment liquid, there is also a demand for obtaining good storage stability of the pretreatment liquid.

[0006] Therefore, an object of the present invention is to provide an ink set that suppresses deterioration of texture when a liquid is ejected and printed onto fabric, that provides good color development and fastness, and that has good storage stability of a pretreatment liquid. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the ink set of the present invention is an ink set for fabric printing comprising a pretreatment liquid and an aqueous ink, wherein the aqueous ink comprises a pigment, the pretreatment liquid comprises an organic acid and an amino-modified silicone, the content of the amino-modified silicone in the pretreatment liquid is 1% by mass or more and less than 15% by mass, and the pKa of the organic acid at 25°C is 2.5 or more and less than 5.0, and the content of the organic acid in the pretreatment liquid is 5% by mass or more and 20% by mass or less. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an ink set that suppresses deterioration of texture when a liquid is ejected and printed onto fabric, that achieves good color development and fastness, and that has good storage stability of a pretreatment liquid. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a liquid ejection device. [Figure 2] FIG. 2 is a schematic diagram illustrating an example of an ink tank. DETAILED DESCRIPTION OF THE INVENTION

[0010] The ink set, liquid ejection device, and liquid ejection method according to the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the following embodiments, and other modifications, additions, corrections, deletions, and other changes can be made within the scope of what a person skilled in the art can conceive. Any aspect that achieves the functions and effects of the present invention is within the scope of the present invention.

[0011] (ink set) The ink set of the present invention is an ink set for fabric printing comprising a pretreatment liquid and an aqueous ink, wherein the aqueous ink comprises a pigment, the pretreatment liquid comprises an organic acid and an amino-modified silicone, the content of the amino-modified silicone in the pretreatment liquid is 1% by mass or more and less than 15% by mass, and the organic acid has a pKa at 25°C of 2.5 or more and less than 5.0, and the content of the organic acid in the pretreatment liquid is 5% by mass or more and 20% by mass or less.

[0012] According to the present invention, it is possible to provide an ink set that suppresses deterioration of texture when a liquid is ejected and printed onto fabric, that achieves good color development and fastness, and that has good storage stability of a pretreatment liquid.

[0013] Hereinafter, the aqueous ink may be referred to as "ink." In addition, in the present invention, the terms "image formation," "recording," "printing," "printing," and the like are all synonymous. The terms "recording medium," "media," and "printed material" are all synonymous.

[0014] <Pretreatment liquid> The pretreatment liquid contains an organic acid and an amino-modified silicone, and may also contain water and an organic solvent, and may optionally contain a surfactant, an antifoaming agent, a pH adjuster, an antiseptic and antifungal agent, an antirust agent, etc. The organic solvent, surfactant, antifoaming agent, pH adjuster, antiseptic and antifungal agent, and antirust agent may be the same materials as those used in ink, and other materials used in known treatment liquids may also be used. Since the materials that can be used in the pretreatment liquid can be the materials described for the ink, the organic acid and amino-modified silicone will be described in particular here, and other details will be omitted.

[0015] <<Organic acids>> The organic acid has a pKa of 2.5 or more and less than 5.0 at 25°C. If it is less than 2.5, corrosion of metal members that come into contact with the pretreatment liquid inside the printer is likely to occur. If it is 5.0 or more, the coagulation action of the ink components, which is the main function of the pretreatment liquid, is weakened, resulting in reduced color development or image bleeding. The pKa at 25°C is preferably 2.8 or more and 4.8 or less.

[0016] Examples of methods for measuring the pKa of the organic acid include titration. pKa is the logarithm of the reciprocal of the acid dissociation constant Ka, and the acid dissociation constant takes a value specific to the acid. Therefore, the pKa of the organic acid can be determined by identifying the organic acid. The organic acid can be identified by separating the components from the mixture using gas chromatography, liquid chromatography, ion chromatography, capillary electrophoresis, or the like, and then identifying them using qualitative analysis methods such as mass spectrometry, infrared absorption spectrometry, and NMR.

[0017] Examples of organic acids include malonic acid (pKa = 2.83, 5.69), citric acid (pKa = 2.8), tartaric acid (pKa = 2.98, 4.34), malic acid (pKa = 3.4), formic acid (pKa = 3.74), lactic acid (pKa = 3.8), succinic acid (pKa = 4.16), acetic acid (pKa = 4.8), sorbic acid (pKa = 4.76), butyric acid (pKa = 4.63), and propionic acid (pKa = 4.85). Polyvalent organic acids such as malonic acid have multiple acid dissociation constants and therefore multiple pKa values, but any one of the pKa values ​​may be greater than or equal to 2.5 and less than 5.0.

[0018] The organic acid is preferably one or more selected from lactic acid, citric acid, and acetic acid, more preferably one or more selected from lactic acid and citric acid. When lactic acid, citric acid, or acetic acid is used as the organic acid, fastness is improved, and when lactic acid or citric acid is used, fastness is further improved.

[0019] The content of the organic acid in the pretreatment liquid is 5% by mass or more and 20% by mass or less. If it is less than 5% by mass, good color development cannot be achieved. If it is more than 20% by mass, it is not preferable from the viewpoint of the composition of the formulation.

[0020] The content of the organic acid in the pretreatment liquid is preferably 5% by mass or more and less than 20% by mass, and more preferably 8% by mass or more and less than 15% by mass. By satisfying this range, the color development, fastness, and texture of the image can be improved, and the storage stability of the pretreatment liquid can be improved.

[0021] <<Amino-modified silicone>> Amino-modified silicone refers to a dimethyl silicone in which some of the methyl groups have been replaced with amino groups. By including amino-modified silicone in the pretreatment liquid, the coefficient of friction between fibers can be reduced, improving the texture of the fabric. Amino-modified silicone can be used, for example, as a cationic surfactant.

[0022] The amino-modified silicone can be selected appropriately, and commercially available products such as AMC-900 (manufactured by Nicca Chemical Co., Ltd.), KF-8004, KF-8015, KF-867S, and KF-8005S (manufactured by Shin-Etsu Chemical Co., Ltd.) can be used.

[0023] The content of the amino-modified silicone in the pre-treatment liquid is 1% by mass or more and less than 15% by mass. If it is less than 1% by mass, a good texture cannot be obtained, and if it is 15% by mass or more, the pre-treatment liquid cannot have good storage stability.

[0024] The content of the amino-modified silicone in the pre-treatment liquid is preferably 5% by mass or more and less than 15% by mass, more preferably 10% by mass or more and less than 15% by mass, and even more preferably 11% by mass or more and 14% by mass or less.Within such a range, the texture is improved.

[0025] <Ink> The water-based inks (also referred to as inks) included in the ink set of the present invention contain a pigment, and may also contain organic solvents, resins, additives, etc. The ink set may contain one type of ink or multiple types of ink, and may contain, for example, one color or multiple colors.

[0026] <<Organic solvents>> The organic solvent used in the present invention is not particularly limited, and any water-soluble organic solvent can be used, including, for example, polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.

[0027] Specific examples of polyhydric alcohols include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, and 1,4-pentanediol. Examples of suitable glycerol include 2,4-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, glycerin, 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3-pentanediol, and petriol.

[0028] Examples of polyhydric alcohol alkyl ethers include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether.

[0029] Examples of polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

[0030] Examples of the nitrogen-containing heterocyclic compound include 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, and γ-butyrolactone.

[0031] Examples of amides include formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide.

[0032] Examples of the amines include monoethanolamine, diethanolamine, and triethylamine.

[0033] Examples of sulfur-containing compounds include dimethyl sulfoxide, sulfolane, and thiodiethanol.

[0034] Other organic solvents include propylene carbonate and ethylene carbonate.

[0035] It is preferable to use an organic solvent having a boiling point of 250° C. or less, since it not only functions as a wetting agent but also provides good drying properties.

[0036] As the organic solvent, polyol compounds having 8 or more carbon atoms and glycol ether compounds are also suitably used. Specific examples of polyol compounds having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.

[0037] Specific examples of glycol ether compounds include polyhydric alcohol alkyl ethers such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether; and polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

[0038] Polyol compounds having 8 or more carbon atoms and glycol ether compounds can improve the permeability of ink when paper is used as the recording medium.

[0039] The content of the organic solvent in the ink is not particularly limited and can be selected appropriately depending on the purpose. From the viewpoint of the drying property and ejection reliability of the ink, however, the content is preferably 10% by mass or more and 60% by mass or less, and more preferably 20% by mass or more and 60% by mass or less.

[0040] <<Wed>> The water content in the ink is not particularly limited and can be selected appropriately depending on the purpose. From the viewpoint of the drying property and ejection reliability of the ink, however, it is preferably 10% by mass or more and 90% by mass or less, and more preferably 20% by mass or more and 60% by mass or less.

[0041] <<Pigments>> The pigment may be an inorganic pigment or an organic pigment. These may be used alone or in combination of two or more. Mixed crystals may also be used as the pigment.

[0042] Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy pigments such as gold and silver pigments, and metallic pigments.

[0043] As inorganic pigments, titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow, as well as carbon black produced by known methods such as the contact method, furnace method, and thermal method can be used.

[0044] In addition, examples of organic pigments that can be used include azo pigments, polycyclic pigments (e.g., phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments), dye chelates (e.g., basic dye chelates and acid dye chelates), nitro pigments, nitroso pigments, and aniline black. Of these pigments, those with good affinity for the solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.

[0045] Specific examples of pigments for black include carbon blacks (CI Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, metals such as copper, iron (CI Pigment Black 11), and titanium oxide, and organic pigments such as aniline black (CI Pigment Black 1).

[0046] In addition, for color, CI Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104, 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, CI Pigment Yellow Ranges 5, 13, 16, 17, 36, 43, 51, CI Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48:2, 48:2 (Permanent Red 2B (Ca)), 48:3, 48:4, 49:1, 52:2, 53:1, 57:1 (Brilliant Carmine 6B), 60:1, 63:1, 63:2, 64:1, 81, 83, 88 , 101 (Red Iron), 104, 105, 106, 108 (Cadmium Red), 112, 114, 122 (Quinacridone Magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, CI Pigment Violet 1 (Rhodamine Lake), 3, 5:1, 16, 19, 23, 38; CI Pigment Blue 1, 2, 15 (Phthalocyanine Blue), 15:1, 15:2, 15:3, 15:4 (Phthalocyanine Blue), 16, 17:1, 56, 60, 63; CI Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc.

[0047] The content of the coloring material in the ink is preferably from 0.1% to 15% by mass, more preferably from 1% to 10% by mass, from the viewpoints of improving image density, good fixability, and ejection stability.

[0048] Methods for dispersing a pigment to obtain an ink include a method of introducing a hydrophilic functional group into a pigment to make it a self-dispersing pigment, a method of dispersing the pigment by coating the surface of the pigment with a resin, and a method of dispersing the pigment using a dispersant.

[0049] As a method for introducing a hydrophilic functional group into a pigment to make it a self-dispersible pigment, for example, a method of adding a functional group such as a sulfone group or a carboxyl group to a pigment (e.g., carbon) to make it dispersible in water can be mentioned.

[0050] One method for dispersing a pigment by coating its surface with a resin is to encapsulate the pigment in microcapsules to make it dispersible in water. This can be rephrased as a resin-coated pigment. In this case, it is not necessary for all of the pigments blended into the ink to be coated with resin; uncoated or partially coated pigments may be dispersed in the ink, provided that the effects of the present invention are not impaired.

[0051] Examples of the method for dispersing using a dispersant include a method for dispersing using a known low molecular weight dispersant or a high molecular weight dispersant, such as a surfactant.

[0052] As the dispersant, for example, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, etc. can be used depending on the pigment.

[0053] As the dispersant, RT-100 (nonionic surfactant) manufactured by Takemoto Yushi Co., Ltd. and sodium naphthalenesulfonate formalin condensate can also be suitably used. The dispersants may be used alone or in combination of two or more.

[0054] <<Pigment dispersions>> Ink can be obtained by mixing a pigment with water, an organic solvent, or other materials. Alternatively, ink can be produced by mixing a pigment with other materials such as water and a dispersant to form a pigment dispersion, and then mixing the resulting mixture with water, an organic solvent, or other materials.

[0055] The pigment dispersion is obtained by mixing and dispersing water, pigment, pigment dispersant, and other components as required, and adjusting the particle size. Dispersion is preferably performed using a disperser.

[0056] Although there are no particular restrictions on the particle size of the pigment in the pigment dispersion, the maximum frequency, calculated as the maximum number, is preferably 20 nm or more and 500 nm or less, and more preferably 20 nm or more and 150 nm or less, in order to improve the dispersion stability of the pigment and image quality such as ejection stability and image density. The particle size of the pigment can be measured using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

[0057] The content of the pigment in the pigment dispersion is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of obtaining good ejection stability and increasing image density, the content is preferably 0.1% by mass or more and 50% by mass or less, and more preferably 0.1% by mass or more and 30% by mass or less.

[0058] It is preferable to filter out coarse particles from the pigment dispersion using a filter, a centrifugal separator or the like, and degas the dispersion, if necessary.

[0059] <<Resin>> The type of resin contained in the ink is not particularly limited and can be selected appropriately depending on the purpose. Examples include urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, styrene-butadiene resin, vinyl chloride resin, acrylic styrene resin, and acrylic silicone resin.

[0060] Resin particles made of these resins may also be used. The resin particles are dispersed in water as a dispersion medium to form a resin emulsion, which can be mixed with materials such as coloring materials and organic solvents to obtain an ink. The resin particles may be appropriately synthesized or commercially available. These may be used alone or in combination of two or more types of resin particles.

[0061] The volume average particle size of the resin particles is not particularly limited and can be appropriately selected depending on the purpose. However, from the viewpoint of obtaining good fixing properties and high image hardness, the volume average particle size is preferably 10 nm or more and 1,000 nm or less, more preferably 10 nm or more and 200 nm or less, and particularly preferably 10 nm or more and 100 nm or less.

[0062] The volume average particle size can be measured, for example, using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

[0063] The resin content is not particularly limited and can be selected appropriately depending on the purpose. From the viewpoint of fixability and ink storage stability, however, the resin content is preferably 8% by mass or more and 15% by mass or less, and more preferably 8% by mass or more and 12% by mass or less, of the total amount of ink.

[0064] There are no particular restrictions on the particle size of the solid content in the ink, and it can be selected appropriately depending on the purpose. To improve image quality, such as ejection stability and image density, the maximum frequency of particle size of the solid content in the ink, calculated in terms of maximum number, is preferably 20 nm or more and 1000 nm or less, and more preferably 20 nm or more and 150 nm or less. The solid content includes resin particles, pigment particles, etc. The particle size can be measured using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

[0065] These urethane resins and acrylic resins may be used as resin particles, as described above. The types of urethane resin particles and acrylic resin particles contained in the ink are not particularly limited and can be appropriately selected depending on the purpose. The ink can be obtained by mixing the resin particles in the form of a resin emulsion in which the resin particles are dispersed using water as a dispersion medium with materials such as colorants and organic solvents. The resin particles may be appropriately synthesized or commercially available products may be used.

[0066] <<Additives>> If necessary, surfactants, antifoaming agents, antiseptic and antifungal agents, antirust agents, pH adjusters, etc. may be added to the ink.

[0067] <<Surfactants>> As the surfactant, any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants and anionic surfactants can be used.

[0068] The silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. Among them, those that do not decompose even at high pH are preferred. Examples of silicone surfactants include side-chain modified polydimethylsiloxane, both-end modified polydimethylsiloxane, one-end modified polydimethylsiloxane, and both-end modified polydimethylsiloxane of the side chain. Those having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as the modifying group are particularly preferred because they exhibit good properties as aqueous surfactants. Furthermore, polyether-modified silicone surfactants can also be used as silicone surfactants, and examples thereof include compounds in which a polyalkylene oxide structure is introduced into the Si part side chain of dimethylsiloxane.

[0069] As fluorosurfactants, for example, perfluoroalkyl sulfonic acid compounds, perfluoroalkyl carboxylic acid compounds, perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in the side chain are particularly preferred due to their low foaming properties. Examples of perfluoroalkyl sulfonic acid compounds include perfluoroalkyl sulfonic acid and perfluoroalkyl sulfonate salts. Examples of perfluoroalkyl carboxylic acid compounds include perfluoroalkyl carboxylic acids and perfluoroalkyl carboxylate salts. Examples of polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in the side chain include sulfate ester salts of polyoxyalkylene ether polymers having perfluoroalkyl ether groups in the side chain, and salts of polyoxyalkylene ether polymers having perfluoroalkyl ether groups in the side chain. Examples of counter ions of the salts in these fluorosurfactants include Li, Na, K, NH, NHCHCHOH, NH(CHCHOH), NH(CHCHOH), and the like.

[0070] Examples of amphoteric surfactants include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.

[0071] Examples of nonionic surfactants include polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkylamines, polyoxyethylene alkylamides, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and ethylene oxide adducts of acetylene alcohol.

[0072] Examples of anionic surfactants include polyoxyethylene alkyl ether acetates, dodecylbenzenesulfonates, laurates, and salts of polyoxyethylene alkyl ether sulfates. These may be used alone or in combination of two or more.

[0073] The silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. Examples include side-chain-modified polydimethylsiloxane, both-end-modified polydimethylsiloxane, one-end-modified polydimethylsiloxane, and both-end-modified side-chain polydimethylsiloxane. Polyether-modified silicone surfactants having polyoxyethylene groups or polyoxyethylene-polyoxypropylene groups as modifying groups are particularly preferred because they exhibit good properties as aqueous surfactants.

[0074] Such surfactants may be appropriately synthesized or commercially available products, such as those available from BYK-Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nippon Emulsion Co., Ltd., and Kyoeisha Chemical Co., Ltd.

[0075] The polyether-modified silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. For example, it may be a surfactant represented by general formula (S-1) in which a polyalkylene oxide structure is introduced into the Si moiety side chain of dimethylpolysiloxane.

[0076] [ka]

[0077] (In the general formula (S-1), m, n, a, and b each independently represent an integer, R represents an alkylene group, and R' represents an alkyl group.)

[0078] As the polyether-modified silicone surfactant, commercially available products can be used, such as KF-618, KF-642, KF-643 (Shin-Etsu Chemical Co., Ltd.), EMALEX-SS-5602, SS-1906EX (Nihon Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (Dow Corning Toray Silicone Co., Ltd.), BYK-33, BYK-387 (BYK-Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicone Co., Ltd.).

[0079] As the fluorine-based surfactant, a compound having 2 to 16 fluorine-substituted carbon atoms is preferred, and a compound having 4 to 16 fluorine-substituted carbon atoms is more preferred.

[0080] Examples of fluorine-based surfactants include perfluoroalkyl phosphate ester compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in the side chains. Among these, polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in the side chains are preferred because they have low foaming properties, and fluorine-based surfactants represented by general formula (F-1) and general formula (F-2) are particularly preferred.

[0081] [ka]

[0082] In the compound represented by the above general formula (F-1), m is preferably an integer of 0 to 10, and n is preferably an integer of 0 to 40 in order to impart water solubility.

[0083] C n F 2n+1 -CH2CH(OH)CH2-O-(CH2CH2O) a -Y General formula (F-2)

[0084] In the compound represented by the general formula (F-2), Y is H or C m F 2m+1 where m is an integer from 1 to 6, or CH2CH(OH)CH2-C m F 2m+1 where m is an integer between 4 and 6, or C p H 2p+1 where p is an integer from 1 to 19, n is an integer from 1 to 6, and a is an integer from 4 to 14.

[0085] As the fluorine-based surfactant, commercially available products may be used, such as Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Fullard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, and FC-431 (all manufactured by Sumitomo 3M Limited); Megafa F-470, F-1405, F-474 (all manufactured by Dainippon Ink and Chemicals, Inc.); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR, Capstone FS-30, FS-31, FS-3100, FS-34, FS-35 (all manufactured by Chemours); FT-110, FT- 250, FT-251, FT-400S, FT-150, FT-400SW (all manufactured by Neos Corporation), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omnova), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.), and among these, FS-3100, FS-34, FS-300 manufactured by Chemours Corporation, FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos Corporation, Polyfox PF-151N manufactured by Omnova, and Unidyne DSN-403N manufactured by Daikin Industries, Ltd. are particularly preferred in terms of achieving good print quality, particularly color development, penetration into paper, wettability, and significant improvements in dye leveling.

[0086] The content of the surfactant in the ink is not particularly limited and can be appropriately selected according to the purpose. However, from the viewpoints of excellent wettability and ejection stability and improved image quality, it is preferably 0.001% by mass or more and 5% by mass or less, more preferably 0.05% by mass or more and 5% by mass or less.

[0087] <<Antifoaming agent>> The antifoaming agent is not particularly limited, and examples thereof include silicone-based antifoaming agents, polyether-based antifoaming agents, fatty acid ester-based antifoaming agents, etc. These may be used alone or in combination of two or more. Among these, silicone-based antifoaming agents are preferred because of their excellent defoaming effect.

[0088] <<Antiseptic and antifungal agent>> The antiseptic and antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one, etc.

[0089] <<Rust preventive>> The rust preventive is not particularly limited, and examples thereof include acid sulfite, sodium thiosulfate, etc.

[0090] <<pH adjuster>> The pH adjuster is not particularly limited as long as it can adjust the pH to 7 or more, and examples thereof include amines such as diethanolamine and triethanolamine.

[0091] <Physical properties of the ink> The physical properties of the ink are not particularly limited and can be appropriately selected according to the purpose. For example, it is preferable that the viscosity, surface tension, pH, etc. are in the following ranges.

[0092] The ink viscosity at 25°C is preferably 5 mPa·s or more and 30 mPa·s or less, and more preferably 5 mPa·s or more and 25 mPa·s or less, in order to improve print density and character quality and obtain good ejection properties. Here, viscosity can be measured using, for example, a rotational viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.). Measurement conditions include 25°C, a standard cone rotor (1°34' x R24), a sample liquid volume of 1.2 mL, a rotation speed of 50 rpm, and 3 minutes.

[0093] The surface tension of the ink is preferably 35 mN / m or less, and more preferably 32 mN / m or less at 25° C., in order to ensure that the ink is properly leveled on the recording medium and the drying time of the ink is shortened.

[0094] The pH of the ink is preferably 7 to 12, and more preferably 8 to 11, from the viewpoint of preventing corrosion of metal members that come into contact with the ink.

[0095] (Recording medium) Examples of recording media used for recording include plain paper, glossy paper, special paper, cloth, film, OHP sheets, and general-purpose printing paper, but in the present invention, cloth is particularly used. The ink set of the present invention is particularly useful for printing on cloth. The cloth can be appropriately selected, and examples thereof include cotton broadcloth and polyester tropical cloth.

[0096] (Liquid ejection device and liquid ejection method) Next, the liquid ejection device and liquid ejection method of the present invention will be described. The liquid ejection device can be used as a recording device, a printing device, an image forming device, an inkjet recording device, an inkjet printing device, etc., and the liquid ejection method can be used as a recording method, a printing method, an image forming method, an inkjet recording method, an inkjet printing method, etc.

[0097] The liquid ejection device of the present invention is a liquid ejection device having the ink set of the present invention, and is characterized by comprising a first ejection means that ejects the pretreatment liquid onto a fabric, and a second ejection means that ejects the water-based ink onto the fabric.

[0098] The liquid ejection method of the present invention is a liquid ejection method using the ink set of the present invention, and is characterized by including a first ejection step of ejecting the pretreatment liquid onto a fabric, and a second ejection step of ejecting the water-based ink onto the fabric.

[0099] In the liquid ejection device and liquid ejection method of the present invention, it is preferable that after ejecting the pretreatment liquid onto the fabric, the aqueous ink is ejected without drying or heating, thereby bringing the pretreatment liquid into contact with the aqueous ink. In this way, the pretreatment liquid and the aqueous ink can be brought into contact with each other in a liquid state, thereby improving color development and texture.

[0100] In the liquid ejection device and liquid ejection method of the present invention, the ratio A:B, which is the ratio of the application amount A of the pretreatment liquid to the application amount B of the water-based ink, is preferably 1:3 to 1:0.4. This makes it possible to improve color development, fastness, and texture. The application amounts A and B are calculated by measuring the weight of a printed item onto which pretreatment liquid A and pretreatment liquid B have been ejected, respectively, on an impermeable plastic film, and then calculating the application amounts from the weight of the film before and after ejection and the area of ​​the ejected image. In the present invention, the application amount refers to the mass per area where the pretreatment liquid and ink are applied. When a liquid ejection device or liquid ejection method that allows the application amounts of the pretreatment liquid and ink to be set is used, it is not necessary to calculate the application amounts using the above calculation method.

[0101] A further explanation will be given below using a recording device and a recording method as examples. The ink set of the present invention can be suitably used in various recording devices using the ink jet recording method, such as printers, facsimile machines, copying machines, printer / fax / copier combination machines, and three-dimensional modeling devices.

[0102] In the present invention, the term "recording apparatus" and "recording method" refer to an apparatus capable of ejecting ink or various treatment liquids onto a recording medium, and a method of recording using the apparatus. The term "recording medium" refers to an object onto which ink or various treatment liquids can be attached, even if only temporarily. This recording device can include not only the head portion that ejects ink, but also means related to feeding, transporting, and discharging the recording medium, as well as other devices called pre-processing devices and post-processing devices.

[0103] The recording apparatus and recording method may have a heating means used in the heating step and a drying means used in the drying step. The heating means and drying means include, for example, means for heating and drying the printed surface and back surface of the recording medium. The heating means and drying means are not particularly limited, but for example, a hot air heater or an infrared heater can be used. Heating and drying can be carried out before, during, or after printing.

[0104] Furthermore, the recording device and recording method are not limited to those that visualize meaningful images such as letters and figures using ink. For example, they also include those that form patterns such as geometric designs and those that create three-dimensional images.

[0105] Furthermore, unless otherwise specified, the recording apparatus includes both a serial type apparatus in which the ejection head moves and a line type apparatus in which the ejection head does not move. Furthermore, this recording device includes not only desktop types, but also wide-width recording devices that can print on A0-sized recording media, and continuous feed printers that can use continuous paper wound into a roll as a recording medium, for example.

[0106] An example of a recording apparatus will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of the apparatus. FIG. 2 is a perspective view of a main tank. An image forming apparatus 400, as an example of a recording apparatus, is a serial image forming apparatus. A mechanism unit 420 is provided within an exterior 401 of the image forming apparatus 400. Each ink storage unit 411 of the main tanks 410 (410k, 410c, 410m, 410y) for each color of black (K), cyan (C), magenta (M), and yellow (Y) is formed from a packaging material such as aluminum laminate film. The ink storage unit 411 is housed in a storage container case 414 made of, for example, plastic. As a result, the main tanks 410 are used as ink cartridges for each color.

[0107] On the other hand, a cartridge holder 404 is provided at the back side of the opening when the cover 401c of the apparatus main body is opened. A main tank 410 is detachably attached to the cartridge holder 404. This allows each ink outlet 413 of the main tank 410 to communicate with an ejection head 434 for each color via a supply tube 436 for each color, making it possible to eject ink from the ejection head 434 onto a recording medium. The pretreatment liquid may be ejected from the ejection head 434 or from another ejection head. The pretreatment liquid is filled into a tank or ink storage section as appropriate. [Example]

[0108] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In the examples, "parts" means "parts by mass" and "%" means "% by mass" except in the evaluation criteria.

[0109] (Preparation of pretreatment solution) <Preparation of pretreatment solution 1> Pretreatment liquid 1 was prepared by using the following pretreatment liquid formulation 1, adding ion-exchanged water to a total amount of 100 parts by mass, mixing and stirring, and filtering through a filter with an average pore size of 5 μm (Minisart, manufactured by Sartorius).

[0110] [Pretreatment solution formulation 1] Citric acid (Kanto Chemical Co., Ltd.): 10 parts by weight Amino-modified silicone AMC-900 (manufactured by Nicca Chemical Co., Ltd.): 53.8 parts by mass Propylene glycol: 20 parts by weight Ion-exchanged water: remaining amount (total: 100 parts by mass)

[0111] <Preparation of pretreatment solutions 2 to 16> Pretreatment solutions 2 to 16 were prepared in the same manner as pretreatment solution 1, except that the pretreatment solution formulations were changed as shown in Tables 1 and 2.

[0112] The details of each component in Tables 1 and 2 are as follows: Lactic acid (Kanto Chemical Co., Ltd.) Acetic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) Malic acid (Fujifilm Wako Pure Chemical Industries, Ltd.) Calcium nitrate tetrahydrate (Fujifilm Wako Pure Chemical Industries, Ltd.) Silicone activator KF-96A-100CS (Shin-Etsu Chemical Co., Ltd.)

[0113] In Tables 1 and 2, the "constituent requirements of the pretreatment liquid" are used to explain whether the pretreatment liquid satisfies the preferred requirements. Pretreatment liquids marked with an "x" correspond to the pretreatment liquids used in the comparative examples.

[0114] [Table 1]

[0115] [Table 2]

[0116] (Ink preparation) <Production of black pigment dispersion> A flask was charged with 11.2 g of styrene, 2.8 g of acrylic acid, 12 g of lauryl methacrylate, 4 g of polyethylene glycol methacrylate, 4 g of styrene macromer, and 0.4 g of mercaptoethanol, and the temperature was raised to 65°C. Next, a mixed solution of 100.8 g of styrene, 25.2 g of acrylic acid, 108 g of lauryl methacrylate, 36 g of polyethylene glycol methacrylate, 60 g of hydroxyethyl methacrylate, 36 g of styrene macromer, 3.6 g of mercaptoethanol, 2.4 g of azobismethylvaleronitrile, and 18 g of methyl ethyl ketone was added dropwise to the flask over 2.5 hours. Then, a mixed solution of 0.8 g of azobismethylvaleronitrile and 18 g of methyl ethyl ketone was added dropwise to the flask over 0.5 hours. After aging at 65°C for 1 hour, 0.8 g of azobismethylvaleronitrile was added, and the mixture was further aged for 1 hour to allow the reaction to proceed. After the reaction was completed, 364 g of methyl ethyl ketone was added to the flask, yielding 800 g of polymer solution A with a solids concentration of 50%. Next, 28 g of polymer solution A, 42 g of carbon black (Black Pearls 1000, manufactured by Cabot Corporation), 13.6 g of 1 mol / L potassium hydroxide aqueous solution, 20 g of methyl ethyl ketone, and 13.6 g of water were thoroughly stirred and then kneaded with a roll mill to obtain a paste. The resulting paste was added to 200 g of pure water and thoroughly stirred, after which the methyl ethyl ketone was removed with an evaporator. The mixture was then pressure-filtered through a polyvinylidene fluoride membrane filter with an average pore size of 5 μm. The water content was adjusted to a solids concentration of 20%, yielding black pigment dispersion 1 with a solids concentration of 20%.

[0117] <Preparation of Ink 1> Ink 1 was prepared by using the following ink formulation 1, adding ion-exchanged water to a total amount of 100 parts by mass, mixing and stirring, and filtering through a filter with an average pore size of 5 μm (Minisart, manufactured by Sartorius).

[0118] [Ink formula 1] The above black pigment dispersion: 20 parts by mass Urethane resin W-6110 (Mitsui Chemicals, Inc., solids concentration 30%, glass transition temperature -20°C): 33.3 parts by weight SAG503A (manufactured by Nissin Chemical Industry Co., Ltd., silicone surfactant, HLB value: 11): 0.1 parts by mass Propylene glycol: 20 parts by weight Proxel LV (Avecia, antiseptic and antifungal agent): 0.1 parts by weight Ion-exchanged water: remaining amount (total: 100 parts by mass)

[0119] <Preparation of Inks 2 to 6> Inks 2 to 5 were prepared in the same manner as Ink 1, except that the ink formulation was changed to that shown in Table 3.

[0120] In Table 3, the details of each component are as follows: Urethane resin Takelac W-6110 (Mitsui Chemicals, Inc., solids concentration 30%, glass transition temperature -20°C) Acrylic resin Nikazol FX-2033 (Nippon Carbide Industries Co., Ltd., solids concentration 30%, glass transition temperature 8°C) Urethane resin SF150 (Superflex 150, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., solid content 30%, glass transition temperature 40°C) Proxel LV (Avecia, antiseptic and antifungal agent) SAG503A (siloxane surfactant, manufactured by Nissin Chemical Industry Co., Ltd.)

[0121] [Table 3]

[0122] (Examples 1 to 17, Comparative Examples 1 to 5) A DTG printer, Ri100 (manufactured by Ricoh Co., Ltd.), was used to produce the printed matter. The ink tank installed in the inkjet printer was filled with the pretreatment liquid and ink obtained above. The pretreatment liquid was applied to a cotton broadcloth (manufactured by Irozome Co., Ltd.) and a polyester tropical fabric (manufactured by Teijin Co., Ltd.) in an amount of 10 g / m. 2After printing, immediately apply black ink at a rate of 20 g / m 2 The cotton fabric was then dried at 160°C for 5 minutes and the polyester fabric at 130°C for 5 minutes using a thermostatic oven to produce the printed matter. The ink sets used in each of the examples and comparative examples are as shown in Tables 4 to 6 below.

[0123] <Evaluation> The printed matter produced in each example and comparative example was evaluated for color development, fastness, texture, and storage stability of the pretreatment liquid. The results are shown in Tables 4 to 6.

[0124] The contact state between the pretreatment liquid and the ink in Example 17 is described as "applying ink to a dried pretreatment layer." In Example 17, the pretreatment liquid was printed and then dried, and then the ink was printed and dried. That is, in Example 18, the pretreatment liquid was printed, and then the cotton fabric was dried at 160°C and the polyester fabric was dried at 130°C for 5 minutes using a thermostatic oven, and then black ink was printed and dried under the same conditions to produce a printed product.

[0125] <<Color development>> The density of the prints made using the inkjet printer was measured using a colorimeter X-Rite (manufactured by X-Rite Corporation) to evaluate the color development. The evaluation criteria are as follows: △ or better is acceptable.

[0126] [Evaluation criteria] 〇: Black density is 1.4 or more △: Black density is 1.25 or more and less than 1.4 ×: Black density is less than 1.25

[0127] <<Robustness>> The prints produced using the inkjet printer were subjected to a wet rub fastness test in accordance with JIS L 0801. The evaluation criteria were as follows: △ or better is acceptable.

[0128] [Evaluation criteria] ◎: Wet friction fastness is grade 5 Good: Wet friction fastness is grade 4 or more but less than grade 5 △: Wet friction fastness is grade 3 or more but less than grade 4 ×: Wet friction fastness less than grade 3

[0129] <<Texture>> The printed matter produced using the inkjet printer was cut into 85 mm squares, and the bending resistance was measured using a Handle-O-Meter (trade name: HOM-200, manufactured by Daiei Scientific Instruments Co., Ltd.). The evaluation criteria were as follows: △ or higher was considered acceptable.

[0130] [Evaluation criteria] ◎: Stiffness less than 20g 〇: Stiffness is 20g or more and less than 35g △: Stiffness is 35g or more and less than 50g ×: Stiffness is 50g or more

[0131] <<Storage stability of pretreatment solution>> Each pretreatment liquid was placed in a polyethylene container, sealed, and stored at 60°C for one week. The viscosity at 25°C was measured before and after each storage period, and the rate of change from the initial viscosity was calculated to evaluate storage stability. The evaluation criteria were as follows: ○ indicates a practically usable level. The viscosity at which the rate of change was greatest for each pretreatment liquid was evaluated. The viscosity of the pretreatment liquid was measured using a cone-plate type rotational viscometer, VISCOMETER TVE-22L, manufactured by Toki Sangyo Co., Ltd., with a cone rotor (1°34' x R24), at a rotation speed of 50 rpm and constant temperature circulating water temperature of 25°C.

[0132] [Evaluation criteria] ○: The rate of change is between 0% and 20% ×: Change rate exceeds 20%

[0133] [Table 4]

[0134] [Table 5]

[0135] [Table 6]

[0136] For example, aspects of the present invention are as follows. <1> An ink set for fabric printing, comprising a pretreatment liquid and a water-based ink, The water-based ink contains a pigment, the pretreatment liquid contains an organic acid and an amino-modified silicone, the content of the amino-modified silicone in the pretreatment liquid is 1% by mass or more and less than 15% by mass, The organic acid has a pKa of 2.5 or more and less than 5.0 at 25°C, and its content in the pretreatment liquid is 5% by mass or more and 20% by mass or less. An ink set characterized by: <2> The content of the amino-modified silicone in the pretreatment liquid is 5% by mass or more and less than 15% by mass. Characterized by <1> The ink set according to claim 1. <3> The content of the amino-modified silicone in the pretreatment liquid is 10% by mass or more and less than 15% by mass. Characterized by <1> The ink set according to claim 1. <4> The organic acid is at least one selected from lactic acid, citric acid, and acetic acid. Characterized by <1> from <3> 1. The ink set according to claim 1 , <5> The organic acid is at least one selected from lactic acid and citric acid. Characterized by <1> from <3> 1. The ink set according to claim 1 , <6> <1> from <5> A liquid ejection device having the ink set according to any one of a first discharge means for discharging the pretreatment liquid onto a fabric; and a second ejection means for ejecting the water-based ink onto the fabric. A liquid ejection device characterized by: <7> After the pretreatment liquid is ejected onto the fabric, the aqueous ink is ejected without drying or heating to bring the aqueous ink into contact with the pretreatment liquid. Characterized by <6> The liquid ejection device according to claim 1. <8> The ratio A:B between the amount A of the pretreatment liquid to the amount B of the water-based ink is 1:3 to 1:0.4. Characterized by <6> or <7> The liquid ejection device according to claim 1. <9> <1> from <5> A liquid ejection method using the ink set according to any one of the preceding claims, a first discharging step of discharging the pretreatment liquid onto a fabric; a second ejection step of ejecting the water-based ink onto the fabric. A liquid ejection method comprising: <10> After the pretreatment liquid is ejected onto the fabric, the aqueous ink is ejected without drying or heating to bring the aqueous ink into contact with the pretreatment liquid. Characterized by <9> The liquid ejection method according to claim 1. <11> The ratio A:B between the amount A of the pretreatment liquid to the amount B of the water-based ink is 1:3 to 1:0.4. Characterized by <9> or <10> The liquid ejection method according to claim 1. [Explanation of symbols]

[0137] 400 Image forming device 401 Exterior of image forming device 401c Device body cover 404 Cartridge Holder 410 Main Tank 410k, 410c, 410m, 410y Main tanks for black (K), cyan (C), magenta (M), and yellow (Y) 411 Ink storage unit 413 Ink outlet 414 Storage container case 420 Mechanism Department 434 Discharge Head 436 Supply Tube [Prior art documents] [Patent documents]

[0138] [Patent Document 1] Japanese Patent Publication No. 2020-051001 [Patent Document 2] Patent Publication No. 2021-152091 [Patent Document 3] Special Publication No. 2021-500437 [Patent Document 4] Japanese Patent Publication No. 2020-105304

Claims

1. An ink set for fabric printing, comprising a pretreatment liquid and a water-based ink, The water-based ink contains a pigment, the pretreatment liquid contains an organic acid and an amino-modified silicone, the content of the amino-modified silicone in the pretreatment liquid is 1% by mass or more and less than 15% by mass, The organic acid has a pKa of 2.5 or more and less than 5.0 at 25°C, and its content in the pretreatment liquid is 5% by mass or more and 20% by mass or less. An ink set characterized by:

2. The content of the amino-modified silicone in the pretreatment liquid is 5% by mass or more and less than 15% by mass. The ink set according to claim 1 .

3. The content of the amino-modified silicone in the pretreatment liquid is 10% by mass or more and less than 15% by mass. The ink set according to claim 1 .

4. The organic acid is at least one selected from lactic acid, citric acid, and acetic acid. The ink set according to claim 1 .

5. The organic acid is at least one selected from lactic acid and citric acid. The ink set according to claim 1 .

6. A liquid ejection device having the ink set according to any one of claims 1 to 5, a first discharge means for discharging the pretreatment liquid onto a fabric; and a second ejection means for ejecting the water-based ink onto the fabric. A liquid ejection device characterized by:

7. After the pretreatment liquid is ejected onto the fabric, the aqueous ink is ejected without drying or heating to bring the aqueous ink into contact with the pretreatment liquid.

7. The liquid ejection device according to claim 6.

8. The ratio A:B between the amount A of the pretreatment liquid to the amount B of the water-based ink is 1:3 to 1:0.

4.

8. The liquid ejection device according to claim 7.

9. A liquid ejection method using the ink set according to any one of claims 1 to 5, a first discharging step of discharging the pretreatment liquid onto a fabric; a second ejection step of ejecting the water-based ink onto the fabric. A liquid ejection method comprising:

10. After the pretreatment liquid is ejected onto the fabric, the aqueous ink is ejected without drying or heating to bring the aqueous ink into contact with the pretreatment liquid.

10. The liquid ejection method according to claim 9.

11. The ratio A:B between the amount A of the pretreatment liquid to the amount B of the water-based ink is 1:3 to 1:0.

4.

10. The liquid ejection method according to claim 9.

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