Ink set for inkjet textile printing, inkjet textile printing method, and inkjet textile printing device

Abstract

An ink set for inkjet textile printing according to one aspect of the present invention comprises a pretreatment liquid, an ink, and a post-treatment liquid. The static surface tension of the pretreatment liquid is higher than the static surface tension of either the ink or the post-treatment liquid.

Description

Inkjet printing ink set, inkjet printing method, and inkjet printing device

[0001] The present invention relates to an ink set for inkjet textile printing, an inkjet textile printing method, and an inkjet textile printing apparatus.

[0002] Examples of methods for forming images on fabric include screen printing and roller printing. Screen printing requires the preparation of a screen frame or the like for each image to be formed, while roller printing requires the preparation of an engraved roller or the like for each image to be formed. For this reason, these printing methods are unsuitable for, for example, high-mix, low-volume production. Furthermore, these printing methods may require the washing off of adhesives or the like, which results in the generation of a relatively large amount of wastewater. In contrast, inkjet recording methods allow for changes in design, color, and the like, simply by changing the digital data. Therefore, printing methods using inkjet recording, i.e., inkjet printing methods, substantially eliminate the need for platemaking processes such as screen frames and engraved rollers, making them suitable for high-mix, low-volume production and significantly reducing the amount of wastewater generated.

[0003] Inkjet recording methods not only eject and deposit ink onto a recording medium, but also eject and deposit a treatment liquid separately from the ink. Specifically, a pretreatment liquid may be ejected onto the recording medium before ejecting the ink, or a posttreatment liquid may be ejected onto the recording medium after ejecting the ink. Examples of inkjet recording methods that deposit a treatment liquid include the inkjet recording method described in Patent Document 1. Patent Document 1 describes an inkjet recording method that includes an aqueous colored ink composition deposition step in which an aqueous colored ink composition is ejected from an inkjet head and deposited onto a recording medium made of a blend of natural and synthetic fibers; a treatment liquid deposition step in which a treatment liquid containing an aggregating agent that aggregates components of the aqueous colored ink composition is deposited onto the recording surface of the recording medium; and an aqueous clear ink composition deposition step in which an aqueous clear ink composition containing resin particles is deposited onto the recording medium. Patent Document 1 discloses that a recorded product with excellent abrasion resistance can be produced.

[0004] Japanese Patent Application Laid-Open No. 2019-142068

[0005] An inkjet printing ink set according to one aspect of the present invention includes a pre-treatment liquid, an ink, and a post-treatment liquid, wherein the static surface tension of the pre-treatment liquid is higher than the static surface tension of either the ink or the post-treatment liquid.

[0006] Fig. 1 is a schematic diagram showing an example of an inkjet textile printing device using an inkjet textile printing ink set according to an embodiment of the present disclosure. Fig. 2 is a perspective view showing the overall configuration of an inkjet printer that can use an inkjet textile printing ink set according to an embodiment of the present disclosure. Fig. 3 is a schematic cross-sectional view taken along line III-III in Fig. 2. Fig. 4 is an enlarged perspective view of the carriage shown in Fig. 2.

[0007] Hereinafter, embodiments of the present disclosure will be described, but the present disclosure is not limited to these.

[0008] [Inkjet Textile Printing Ink Set] An inkjet textile printing ink set according to an embodiment of the present disclosure includes a pretreatment liquid, an ink, and a post-treatment liquid. The static surface tension (Spre) of the pretreatment liquid is higher than the static surface tension of both the ink and the post-treatment liquid. That is, the static surface tension (Spre) of the pretreatment liquid is higher than the static surface tension (Si) of the ink (Spre > Si). The static surface tension (Spre) of the pretreatment liquid is higher than the static surface tension (Spost) of the post-treatment liquid (Spre > Spost). When inkjet textile printing is performed using the inkjet textile printing ink set, an image (note that letters are also a type of image) in which bleeding is sufficiently suppressed can be formed on a fabric. That is, when the pre-treatment liquid, the ink, and the post-treatment liquid are sequentially inkjet-discharged onto the fabric, with the ratios Spre>Si and Spre>Spost being controlled, bleeding of the image formed on the fabric can be effectively suppressed. This is believed to be due to the following reasons.

[0009] When Spre>Si, when the ink is applied to a fabric with the pretreatment liquid already applied to the fabric, the ink penetrates in the thickness direction of the fabric rather than spreading in the surface direction (horizontal direction) of the fabric, thereby suppressing bleeding. This is thought to be due to the following: When the pretreatment liquid is applied to the fabric, the pretreatment liquid penetrates in the thickness direction (vertical direction) of the fabric. When the ink is applied to the fabric in this state, the penetration of the ink follows the penetration of the pretreatment liquid, and the ink also penetrates in the thickness direction of the fabric. For this reason, it is thought that the ink penetrates in the thickness direction of the fabric rather than spreading in the surface direction (horizontal direction) of the fabric, thereby suppressing bleeding.

[0010] When Spre>Spost, even if the post-treatment liquid is applied to the fabric while the pre-treatment liquid and the ink are present on the fabric, the ink is less likely to spread in the surface direction (horizontal direction) of the fabric, and bleeding can be suppressed. This is thought to be due to the following: It is thought that the penetration of the post-treatment liquid follows the range where the mixture of the pre-treatment liquid and the ink is present near the surface of the fabric. In contrast, when Spost>Spre, it is thought that the post-treatment liquid does not mix with the mixture of the pre-treatment liquid and the ink, but pushes the mixture, causing it to spread in the horizontal direction of the fabric, resulting in bleeding. When Spre>Spost, it is thought that this spreading of the mixture in the horizontal direction of the fabric can be suppressed, and bleeding can be suppressed.

[0011] From the above, by using an inkjet printing ink set including a pre-treatment liquid, ink, and post-treatment liquid, in which Spre>Si and Spre>Spost, in an inkjet printing method, it is possible to form an image (note that letters are also a type of image) on a fabric in which the occurrence of bleeding is sufficiently suppressed.

[0012] As described above, the inkjet printing ink set according to this embodiment includes a pretreatment liquid, ink, and a posttreatment liquid. When using such an ink set in an inkjet textile printing method, the pretreatment liquid may include, for example, a treatment liquid containing an aggregating agent that forms aggregates with the coloring material in the ink. By applying the pretreatment liquid to a fabric before ink ejection, it is expected that the abrasion fastness of the image formed on the fabric will be improved. Furthermore, in the inkjet textile printing method, the posttreatment liquid may include, for example, a treatment liquid containing resin particles that is ejected onto the fabric after ink deposition. This is expected to improve the fixability of the image formed on the fabric. By applying the pretreatment liquid and posttreatment liquid in this manner in the inkjet textile printing method, the abrasion fastness and fixability of the image formed on the fabric can be improved. However, simply applying the pretreatment liquid and posttreatment liquid in this manner may result in ink bleeding in the image formed by applying the ink to the fabric. For this reason, inkjet textile printing methods are required to be able to form images on fabrics in which bleeding is sufficiently suppressed. Therefore, an ink set comprising a pre-treatment liquid, ink, and a post-treatment liquid for use in inkjet textile printing methods is required to be an ink set that can form images on fabrics in which bleeding is sufficiently suppressed. The inkjet textile printing ink set according to one embodiment of the present disclosure satisfies this requirement, that is, is an ink set that can form images on fabrics in which bleeding is sufficiently suppressed.

[0013] The difference between Spre and Si, i.e., the difference obtained by subtracting Si from Spre (Spre-Si), exceeds 0 and, from the viewpoint of further suppressing the occurrence of bleeding, is preferably, for example, 0.5 mN / m or more and 5.5 mN / m or less, and more preferably 0.5 mN / m or more and 4.5 mN / m or less.

[0014] The difference between Spre and Spost, i.e., the difference obtained by subtracting Spost from Spre (Spre-Spost), is preferably greater than 0 and is, for example, from 1 mN / m to 10 mN / m inclusive, in order to further suppress the occurrence of bleeding.

[0015] The difference between Si and Spost is not particularly limited as long as the relationships Spre > Si and Spre > Spost are satisfied, but from the viewpoint of further suppressing bleeding, it is preferably, for example, 0 mN / m or more and 5 mN / m or less, and more preferably 0 mN / m or more and 3 mN / m or less. Furthermore, from the viewpoint of further suppressing bleeding, the difference obtained by subtracting Spost from Si (Si - Spost) is, for example, preferably -3 mN / m or more and 5 mN / m or less, and more preferably 0.5 mN / m or more and 3 mN / m or less. Furthermore, from the viewpoint of further suppressing bleeding, the static surface tension (Si) of the ink may be higher than the static surface tension (Spost) of the post-treatment liquid (Si > Spost). In this case, Si - Spost will exceed 0, and the upper limit thereof is, for example, preferably 5 mN / m or less, and more preferably 3 mN / m or less.

[0016] The static surface tension may be, for example, a static surface tension at 25° C., and specifically may be a value measured by the Wilhelmy method in a measurement environment of 25° C. The static surface tension may be measured by the Wilhelmy method using, for example, an automatic surface tensiometer (DY-300 manufactured by Kyowa Interface Science Co., Ltd.).

[0017] The fabric is an object to be printed in an inkjet printing method, and may be, for example, a product containing fiber, or may be a product made of fiber. Examples of the fabric include woven fabrics, knitted fabrics, nonwoven fabrics, and braided fabrics. Examples of the fiber include natural fibers such as cotton, silk, wool, and linen; chemical fibers such as polyester, acrylic, polyurethane, polyamide, rayon, cupra, and acetate; and blends thereof. The fabric may contain one of these fibers alone or two or more of them in combination. More specifically, examples of the fabric include cotton fabric, silk fabric, linen fabric, polyester fabric, acetate fabric, rayon fabric, polyamide fabric, and polyurethane fabric. The fabric may also be polyester tropical fabric, which is a plain-woven fabric made of polyester yarn. These fabrics may be used alone or in combination.

[0018] (Pretreatment Liquid) The pretreatment liquid is a treatment liquid that is ejected onto and adhered to a fabric, which is a target of textile printing, before the ink is ejected onto the fabric. The pretreatment liquid is not particularly limited as long as it can be used as a pretreatment liquid in an inkjet textile printing method and its static surface tension (Spre) satisfies the above-mentioned relationship (Spre > Si and Spre > Spost). Examples of the pretreatment liquid include a pretreatment liquid containing a cationic compound. The cationic compound contained in this pretreatment liquid reacts with and aggregates with a coloring material, such as a pigment, contained in the ink that is subsequently ejected, thereby ensuring excellent color development. The pretreatment liquid may also contain an aqueous medium as a main component (e.g., 50% by mass or more) and, if necessary, may contain a surfactant or the like.

[0019] The cationic compound is not particularly limited as long as it is a cationic compound that can aggregate the coloring material contained in the ink upon contact with the ink. Examples of the cationic compound include cationic polymers such as ammonium-containing polymers, amine-containing polymers, polyallylamine, polyvinylamine, polyimine, polyvinylpyrrolidone, polyethyleneimine, polyvinylpyridine, aminoacetalized polyvinyl alcohol, ionene polymers, polyvinylimidazole, polyvinylbenzylphosphonium, polyalkylallylammonium, polyamidine, and polyamine sulfone. The cationic polymer may be water-soluble. That is, the cationic polymer may be a water-soluble cationic polymer. Among these, examples of the cationic compound that can provide better color development include quaternary ammonium-containing polymers, diallyldimethylammonium sulfur dioxide copolymers, diallyldimethylammonium chloride acrylamide copolymers, diallyldimethylammonium chloride polymers, dimethylamine-ammonia-epichlorohydrin polycondensates, and dimethylamine-ammonia-epichlorohydrin polycondensates. These may be used alone or in combination of two or more.

[0020] The weight average molecular weight of the cationic compound is not particularly limited, but is preferably 1,000 or more and 10,000 or less in terms of improving ejection properties from an inkjet head.

[0021] The content of the cationic compound is not particularly limited, but from the viewpoint of further enhancing color development (image density), for example, the lower limit of the content of the cationic compound is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, relative to the total amount of the pretreatment liquid, and the upper limit of the content of the cationic compound is preferably 35% by mass or less, more preferably 29.5% by mass or less, and even more preferably 20% by mass or less.

[0022] The pretreatment liquid may contain an aqueous medium as a main component (for example, 50% by mass or more), and the balance other than the cationic compound and the surfactant described below may be the aqueous medium.

[0023] The aqueous medium contained in the pretreatment liquid is not particularly limited as long as it contains water. For example, it may be an aqueous medium containing water as a main component (e.g., 50% by mass or more) or may be an aqueous medium consisting of water. Furthermore, the aqueous medium may function as a solvent or a dispersion medium in the pretreatment liquid. The content of the water relative to the aqueous medium is, for example, preferably 50% by mass or more, more preferably 90% by mass or more, and may even be 100% by mass. Furthermore, the aqueous medium may contain water and an organic solvent. That is, the aqueous medium may be an aqueous medium containing water and an organic solvent. When the organic solvent is contained, the content of the organic solvent relative to the total amount of the pretreatment liquid is preferably, for example, 3% by mass or more and 50% by mass or less, from the viewpoint of obtaining a pretreatment liquid having a viscosity that allows stable ejection and that is inhibited from drying.

[0024] Examples of the organic solvent include glycol compounds, alcohol compounds (e.g., polyhydric alcohols), ether compounds (e.g., ether compounds of polyhydric alcohols), nitrogen-containing compounds, sulfur-containing compounds, aliphatic hydrocarbons, ketone compounds, ester compounds, vegetable oils, and alkylene carbonates.

[0025] Examples of the glycol compound include ethylene glycol, 1,3-propanediol, propylene glycol, 1,2-pentanediol, 1,5-pentanediol, 1,2-octanediol, 1,8-octanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, and tetraethylene glycol.

[0026] Examples of the polyhydric alcohol include a diol compound having 5 to 8 carbon atoms (first diol compound), a diol compound having 2 to 4 carbon atoms (second diol compound), 1,2,6-hexanetriol, glycerin, trimethylolpropane, sugar alcohols (e.g., xylitol), and sugars (e.g., xylose, glucose, and galactose).

[0027] Examples of the first diol compound include 2-methylpentane-2,4-diol, triethylene glycol, tetraethylene glycol, 1,5-pentanediol, and 1,2-hexanediol.

[0028] Examples of the second diol compound include ethylene glycol, 1,2-propanediol, 1,3-propanediol, butylene glycol, and diethylene glycol.

[0029] Examples of the alcohol compound other than the polyhydric alcohol include methanol, ethanol, isopropanol, butanol, and benzyl alcohol.

[0030] Examples of the ether compounds include ether compounds of polyhydric alcohols. Examples of the ether compounds of polyhydric alcohols include glycol ether compounds and ethylene oxide adducts of diglycerin. Examples of the glycol ether compounds include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol diethyl ether, diethylene glycol diethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, and dipropylene glycol monobutyl ether.

[0031] Examples of the nitrogen-containing compound include lactam compounds, 1,3-dimethylimidazolidinone, formamide, dimethylformamide, and triethanolamine. Examples of the lactam compound include pyrrolidones such as 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexylpyrrolidone, and N-methyl-2-pyrrolidone.

[0032] Examples of the sulfur-containing compound include thiodiethanol, thiodiglycerol, sulfolane, and dimethyl sulfoxide.

[0033] Examples of the aliphatic hydrocarbons include linear hydrocarbons, isoparaffinic hydrocarbons, and naphthenic hydrocarbons.

[0034] Examples of the ketone compound include methyl ethyl ketone.

[0035] Examples of the ester compounds include acetate compounds such as diethylene glycol monoethyl ether acetate.

[0036] Examples of the vegetable oil include soybean oil, linseed oil, rice bran oil, tung oil, castor oil, dehydrated castor oil, corn oil, safflower oil, South Sea tung oil, recycled vegetable oil, canola oil, rapeseed oil, tung oil, peanut oil, cottonseed oil, sesame oil, sunflower oil, olive oil, palm oil, palm kernel oil, coconut oil, and the like, as well as thermally polymerized oils and oxidatively polymerized oils thereof.

[0037] Examples of the alkylene carbonate include propylene carbonate and ethylene carbonate.

[0038] Among the organic solvents described above, glycol compounds are preferably used as the organic solvent. The organic solvents may be used alone or in combination of two or more.

[0039] The content of the aqueous medium is not particularly limited and may be the remainder (the remainder of components other than the aqueous components, such as the cationic compound and the surfactant described below), and is, for example, preferably from 5% by mass to 70% by mass, and more preferably from 10% by mass to 60% by mass, relative to the total amount of the pretreatment liquid.

[0040] The pretreatment liquid may contain a surfactant for purposes such as adjusting surface tension. Furthermore, the inclusion of a surfactant in the pretreatment liquid improves the wettability of the pretreatment liquid with respect to the fabric to be printed. The surfactant is not particularly limited, but may be any of a nonionic surfactant, a cationic surfactant, an anionic surfactant, an amphoteric surfactant, and the like. The HLB value of the surfactant is not particularly limited, but is preferably, for example, 3 to 20, more preferably 6 to 16, and even more preferably 7 to 10, in order to facilitate the Spre satisfying the above relationship (Spre > Si and Spre > Spost). The HLB value of the surfactant is calculated, for example, by the Griffin method using the formula "HLB value = 20 × (sum of formula weights of hydrophilic moieties) / molecular weight."

[0041] Examples of the nonionic surfactant include silicone surfactants such as polyether-modified silicone, and acetylene glycol surfactants such as acetylene diol ethylene oxide adducts.

[0042] Examples of the cationic surfactant include quaternary ammonium surfactants and amine surfactants.

[0043] Examples of the anionic surfactant include carboxylic acid surfactants, carboxylate surfactants, and sulfate ester surfactants.

[0044] Examples of the amphoteric surfactant include carboxylate-type amphoteric surfactants, sulfate-type amphoteric surfactants, sulfonate-type amphoteric surfactants, and phosphate-type amphoteric surfactants.

[0045] The surfactants may be used alone or in combination of two or more.

[0046] The surfactant may be a nonionic surfactant, which makes it easier for Spre to satisfy the above relationships (Spre > Si and Spre > Spost). The surfactant may also be an acetylene glycol surfactant or an acetylene diol ethylene oxide adduct, which makes it easier for Spre to satisfy the above relationships (Spre > Si and Spre > Spost). The surfactant may also be a silicone surfactant or a polyether-modified silicone, which makes it easier for Spre to satisfy the above relationships (Spre > Si and Spre > Spost).

[0047] The content of the surfactant is not particularly limited, but is preferably from 0.05% to 5% by mass, and more preferably from 0.1% to 5% by mass, relative to the total amount of the pretreatment liquid, from the viewpoint of further suppressing bleeding. Furthermore, the content of the surfactant is more preferably from 0.7% to 1.1% by mass, from the viewpoint of making it easier for Spre to satisfy the above-mentioned relationships (Spre>Si and Spre>Spost) and further suppressing bleeding.

[0048] The static surface tension (Spre) of the pretreatment liquid is not particularly limited as long as the above relationships (Spre>Si and Spre>Spost) are satisfied. The upper limit of Spre is, for example, preferably 45 mN / m or less, more preferably 40 mN / m or less, and even more preferably 39 mN / m or less. The lower limit of Spre is, for example, preferably 24 mN / m or more, more preferably 25 mN / m or more, and even more preferably 32 N / m or more.

[0049] The static surface tension (Spre) of the pretreatment liquid can be adjusted, for example, by the composition of the pretreatment liquid. More specifically, it can be adjusted by the type of surfactant contained in the pretreatment liquid, or by the content of the surfactant. Note that the inkjet printing ink set is not limited to a specific method for adjusting Spre, as long as it satisfies the above relationships (Spre>Si and Spre>Spost).

[0050] The pretreatment liquid may further contain known additives (more specifically, a dissolution stabilizer, a drying inhibitor, an antioxidant, a viscosity adjuster, a pH adjuster, an anti-mold agent, etc.) as needed.

[0051] The pretreatment liquid is produced by, for example, mixing the cationic compound, the aqueous medium, and optional components (e.g., surfactants) using a stirrer. The mixing time is not particularly limited, and is preferably, for example, from 1 minute to 30 minutes.

[0052] (Ink) The ink is not particularly limited as long as it can be used in an inkjet printing method and the static surface tension (Si) satisfies the above-mentioned relationship (Spre>Si). Examples of the ink include inks containing a colorant and an aqueous medium. Furthermore, the ink may contain at least one selected from the group consisting of binder resin particles and surfactants, as necessary.

[0053] The coloring material is not particularly limited as long as it is a coloring material contained in ink in an inkjet printing method, and examples thereof include pigments. Examples of the pigment include dispersible pigments that are dispersed in an aqueous medium such as water. The volume median diameter (D ５０ From the viewpoint of obtaining an ink excellent in image density, hue, and color stability, the volume median diameter (D ５０ ) is the median diameter measured using a laser diffraction / scattering particle size distribution measuring device (for example, LA-950 manufactured by Horiba, Ltd.).

[0054] The pigment is not particularly limited as long as it can form a desired image (i.e., can express the colors that constitute the desired image), and examples thereof include known organic pigments and inorganic pigments. Examples of organic pigments include azo pigments, polycyclic pigments, nitro pigments, nitroso pigments, and aniline black. Examples of azo pigments include azo lake pigments, insoluble azo pigments, condensed azo pigments, and chelate azo pigments. Examples of polycyclic pigments include phthalocyanine pigments, perylene pigments, anthraquinone pigments, quinacridone pigments, dioxandinone pigments, thioindigo pigments, isoindolinone pigments, and quinophthaloni pigments. Examples of inorganic pigments include carbon blacks such as acetylene black and lamp black.

[0055] The pigments can also be classified according to color, and examples thereof include yellow pigments, orange pigments, red pigments, blue pigments, green pigments, and black pigments.

[0056] Examples of the yellow pigment include C.I. Pigment Yellow 12, C.I. Pigment Yellow 13, C.I. Pigment Yellow 14, C.I. Pigment Yellow 15, C.I. Pigment Yellow 17, C.I. Pigment Yellow 74, C.I. Pigment Yellow 93, C.I. Pigment Yellow 94, C.I. Pigment Yellow 95, C.I. Pigment Yellow 109, C.I. Pigment Yellow 110, Pigment Yellow 120, C.I. Pigment Yellow 128, C.I. Pigment Yellow 138, C.I. Pigment Yellow 139, C.I. Pigment Yellow 151, C.I. Pigment Yellow 154, C.I. Pigment Yellow 155, C.I. Examples of pigments that can be used include C.I. Pigment Yellow 173, C.I. Pigment Yellow 180, C.I. Pigment Yellow 185, and C.I. Pigment Yellow 193.

[0057] Examples of the orange pigment include C.I. Pigment Orange 31, C.I. Pigment Orange 34, C.I. Pigment Orange 36, C.I. Pigment Orange 43, C.I. Pigment Orange 61, C.I. Pigment Orange 63, and C.I. Pigment Orange 71.

[0058] Examples of the red pigment include C.I. Pigment Red 2, C.I. Pigment Red 3, C.I. Pigment Red 5, C.I. Pigment Red 6, C.I. Pigment Red 7, C.I. Pigment Red 15, C.I. Pigment Red 16, C.I. Pigment Red 48:1, C.I. Pigment Red 53:1, C.I. Pigment Red 57:1, C.I. Pigment Red 122, C.I. Pigment Red 123, C.I. Pigment Red 139, C.I. Pigment Red 144, C.I. Pigment Red 149, C.I. Pigment Red 150, C.I. Pigment Red 166, C.I. Examples of pigments include C.I. Pigment Red 177, C.I. Pigment Red 178, C.I. Pigment Red 202, and C.I. Pigment Red 222.

[0059] Examples of the blue pigment include C.I. Pigment Blue 15, C.I. Pigment Blue 15:2, C.I. Pigment Blue 15:3, and C.I. Pigment Blue 16.

[0060] Examples of the green pigment include C.I. Pigment Green 7.

[0061] Examples of the black pigment include C.I. Pigment Black 7.

[0062] As the coloring material, the pigments may be used alone or in combination of two or more.

[0063] When the ink is used together with the pretreatment liquid as in this embodiment, the pigment may be an anionic pigment for the following reasons: The anionic pigment forms an ionic bond with the cationic compound contained in the pretreatment liquid on the surface of the recording medium, causing the anionic pigment and the cationic compound to aggregate. This aggregation of the anionic pigment and the cationic compound can prevent binder resin particles (described below) contained in the ink from penetrating into the recording medium. This is particularly important when the recording medium is a fabric, as it can prevent the binder resin particles from penetrating into the gaps between the fibers that make up the fabric and binding these fibers together. This can improve the texture (feel, etc.) of the fabric that is the subject of textile printing.

[0064] Examples of the anionic pigment include pigments having an anionic group such as a carboxy group, a sulfonic acid group, a phosphoric acid group, a phosphonic acid group, a phenylphosphonic acid group, and a phenylcarboxy group (pigments into which an anionic group has been introduced).

[0065] The content of the coloring material (pigment) is not particularly limited, but from the viewpoint of increasing image density while maintaining high ink fluidity, it is preferably 1% by mass or more and 12% by mass or less, and more preferably 1% by mass or more and 7% by mass or less, relative to the total amount of the ink. A high content of the coloring material (pigment) (for example, 1% by mass or more) tends to increase image density, while a low content of the coloring material (pigment) (for example, 12% by mass or less) increases ink fluidity.

[0066] The aqueous medium contained in the ink is not particularly limited as long as it contains water, and examples thereof include the same aqueous medium as the aqueous medium contained in the pretreatment liquid, such as the same organic solvent contained in the aqueous medium and its content. When the organic solvent is contained, the content of the organic solvent is preferably, for example, 3% by mass or more and 50% by mass or less relative to the total amount of the ink, from the viewpoint of obtaining an ink with a viscosity that allows stable ejection and that is inhibited from drying. Furthermore, the aqueous medium may function as a solvent or a dispersion medium in the ink. The content of the aqueous medium is not particularly limited and may be the remainder (the remainder of components other than the aqueous components, such as the colorant, binder resin particles described below, and surfactants described below), and is preferably, for example, 5% by mass or more and 70% by mass or less, and more preferably 10% by mass or more and 60% by mass or less relative to the total amount of the ink.

[0067] The ink may contain binder resin particles for the purpose of improving image fixation. The binder resin particles may be present in a dispersed state in an aqueous medium. The binder resin particles can function as a binder that binds the fabric, which is the object of textile printing, to a coloring material such as a pigment. Therefore, by including the binder resin particles in the ink, a printed product with excellent image fixation can be obtained.

[0068] The resin contained in the binder resin particles is not particularly limited, and examples thereof include urethane resin, acrylic resin, methacrylic resin, styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, styrene-maleic acid copolymer, vinylnaphthalene-acrylic acid copolymer, vinylnaphthalene-methacrylic acid copolymer, and vinylnaphthalene-maleic acid copolymer. Among these, urethane resin is preferred as the resin contained in the binder resin particles. The content of urethane resin in the binder resin particles is preferably 80% by mass or more, and may be 100% by mass. In other words, the binder resin particles may be particles made of urethane resin.

[0069] The content of the binder resin particles is not particularly limited, but from the viewpoint of improving image fixation and maintaining stable ink ejection, it is preferably 1% by mass or more and 20% by mass or less, and more preferably 2% by mass or more and 10% by mass or less, relative to the total amount of the ink. A high content of the binder resin particles (for example, 1% by mass or more) tends to improve image fixation, while a low content of the binder resin particles (for example, 20% by mass or less) allows stable ink ejection.

[0070] The ink may contain a surfactant for purposes such as adjusting surface tension. Furthermore, the inclusion of a surfactant in the ink improves the wettability of the ink to the fabric to be printed. The surfactant is not particularly limited, but may be any of a nonionic surfactant, a cationic surfactant, an anionic surfactant, an amphoteric surfactant, and the like. The HLB value of the surfactant is not particularly limited, but is preferably, for example, 3 to 20, more preferably 6 to 16, and even more preferably 7 to 10, in order to facilitate the Si content satisfying the relationship (Spre > Si). Examples of the surfactant include the same surfactants as those contained in the pretreatment liquid. The surfactant may be a nonionic surfactant in order to facilitate the Si content satisfying the relationship (Spre > Si). The surfactant may be an acetylene glycol-based surfactant or an acetylene diol ethylene oxide adduct in order to facilitate the Si content satisfying the relationship (Spre > Si). The surfactant may be a silicone surfactant or a polyether-modified silicone, since this makes it easier for Si to satisfy the above relationship (Spre>Si).

[0071] The content of the surfactant is not particularly limited, but from the viewpoint of further suppressing bleeding, it is, for example, preferably from 0.06% to 5% by mass, more preferably from 0.1% to 5% by mass, and more preferably from 0.5% to 2% by mass, relative to the total amount of the ink. Furthermore, from the viewpoint of making it easier for Si to satisfy the relationship (Spre>Si) and further suppressing bleeding, it is particularly preferable that the content of the surfactant be from 0.7% to 1.4% by mass.

[0072] The static surface tension (Si) of the ink is not particularly limited as long as the above relationship (Spre>Si) is satisfied. The upper limit of Spre is, for example, preferably 38 mN / m or less, more preferably 37 mN / m or less, and even more preferably 34.5 mN / m or less. The lower limit of Si is, for example, preferably 20 mN / m or more, more preferably 21 mN / m or more, and even more preferably 28 N / m or more.

[0073] The static surface tension (Si) of the pretreatment liquid can be adjusted, for example, by the composition of the ink. More specifically, it can be adjusted by the type of surfactant contained in the ink, or by the content of the surfactant. Note that the inkjet printing ink set is not limited to a specific method for adjusting Si, as long as it satisfies the above relationships (Spre>Si and Spre>Spost).

[0074] The ink may further contain known additives (more specifically, a dissolution stabilizer, an anti-drying agent, an antioxidant, a viscosity adjuster, a pH adjuster, an anti-mold agent, etc.) as needed.

[0075] The ink is produced by, for example, using a mixer to mix the colorant (pigment), the aqueous medium, and optional components (for example, binder resin particles, surfactants, etc.) The mixing time is not particularly limited, and is preferably, for example, from 1 minute to 30 minutes.

[0076] (Post-treatment liquid) The post-treatment liquid is a treatment liquid that is ejected and applied to a fabric, which is the object of textile printing, after the ink has been applied to the fabric. The post-treatment liquid is not particularly limited as long as it can be used as a post-treatment liquid in an inkjet textile printing method and its static surface tension (Spost) satisfies the above-mentioned relationship (Spre > Spost). Examples of the post-treatment liquid include a post-treatment liquid containing a silicone oil emulsion. By including the silicone oil emulsion in the post-treatment liquid, the slipperiness of the fabric surface can be improved and the friction fastness can be enhanced. Furthermore, the post-treatment liquid may contain an aqueous medium as a main component (e.g., 50% by mass or more) and may contain a surfactant, if necessary.

[0077] The silicone oil is not particularly limited, and can be exemplified by dimethylsilicone oil, amino group-containing silicone oil, carboxy group-containing silicone oil, phenolic hydroxy group-containing silicone oil, silanol group-containing silicone oil, epoxy group-containing silicone oil, mercapto group-containing silicone oil, phenyl group-containing silicone oil, long-chain alkyl group-containing silicone oil etc.The silicone oil emulsion can be the emulsion that contains one of these silicone oils alone, or can be the emulsion that contains two or more of them in combination.In addition, the silicone oil emulsion itself can be used alone, or can be used in combination of two or more.

[0078] The content of the silicone oil emulsion is not particularly limited, but from the viewpoint of improving the rub fastness, it is preferably, for example, from 1% by mass to 35% by mass relative to the total amount of the post-treatment liquid.

[0079] The aqueous medium contained in the post-treatment liquid is not particularly limited as long as it contains water, and examples thereof include the same aqueous medium as the pre-treatment liquid and the ink, for example, the same organic solvent contained in the aqueous medium and its content. When the organic solvent is contained, the content of the organic solvent may be, for example, 3% by mass or more and 50% by mass or less relative to the total amount of the ink, from the viewpoint of obtaining a post-treatment liquid having a viscosity that allows stable ejection and that is inhibited from drying. Furthermore, the aqueous medium may function as a solvent or a dispersion medium in the post-treatment liquid. The content of the aqueous medium is not particularly limited and may be the remainder of the silicone oil emulsion, etc., and is preferably, for example, 50% by mass or more and 90% by mass or less, and more preferably 55% by mass or more and 70% by mass or less, relative to the total amount of the post-treatment liquid.

[0080] The post-treatment liquid may contain a surfactant for the purpose of adjusting the surface tension, etc. Furthermore, the inclusion of a surfactant in the post-treatment liquid also improves the wettability of the post-treatment liquid with respect to the fabric to be recorded. The surfactant is not particularly limited, but may be any of a nonionic surfactant, a cationic surfactant, an anionic surfactant, an amphoteric surfactant, etc. The HLB value of the surfactant is not particularly limited, but from the viewpoint of making it easier for Spost to satisfy the above relationship (Spre > Spost), it is, for example, preferably from 3 to 20, more preferably from 6 to 16, and even more preferably from 7 to 10. Furthermore, examples of the surfactant include the same surfactants as those contained in the pre-treatment liquid and the ink. Furthermore, from the viewpoint of making it easier for Spost to satisfy the above relationship (Spre > Spost), the surfactant may be a nonionic surfactant. The surfactant may be an acetylene glycol surfactant or an acetylene diol ethylene oxide adduct, from the viewpoint of making it easier for Spost to satisfy the above-mentioned relationship (Spre > Spost).The surfactant may be a silicone surfactant or a polyether-modified silicone, from the viewpoint of making it easier for Spost to satisfy the above-mentioned relationship (Spre > Spost).

[0081] The content of the surfactant is not particularly limited, but is preferably from 0 to 5% by mass, and more preferably from 0.1 to 5% by mass, relative to the total amount of the post-treatment liquid, from the viewpoint of further suppressing bleeding. Furthermore, the content of the surfactant is more preferably from 0 to 1.1% by mass, from the viewpoint of making it easier for Spost to satisfy the relationship (Spre>Spost) and further suppressing bleeding.

[0082] The static surface tension (Spost) of the post-treatment liquid is not particularly limited as long as the above relationship (Spre>Spost) is satisfied. The upper limit of Spost is, for example, preferably 38 mN / m or less, more preferably 37 mN / m or less, and even more preferably 31 mN / m or less. The lower limit of Spost is, for example, preferably 20 mN / m or more, more preferably 21 mN / m or more, and even more preferably 24 N / m or more.

[0083] The static surface tension (Spost) of the post-treatment liquid can be adjusted, for example, by the composition of the post-treatment liquid. More specifically, it can be adjusted by the type of surfactant contained in the post-treatment liquid, or by the content of the surfactant. Note that the inkjet printing ink set is not limited to a method for adjusting Spost, as long as it satisfies the above relationships (Spre>Si and Spre>Spost).

[0084] The post-treatment liquid may further contain known additives (more specifically, a dissolution stabilizer, a drying inhibitor, an antioxidant, a viscosity adjuster, a pH adjuster, an anti-mold agent, etc.) as needed.

[0085] The post-treatment liquid is produced by, for example, using a stirrer to mix the silicone oil emulsion, the aqueous medium, and optional components. The mixing time is not particularly limited, but is preferably, for example, from 1 minute to 30 minutes.

[0086] (Ink Set) The ink set for inkjet textile printing may include the pretreatment liquid, the ink, and the post-treatment liquid, and may include, for example, an ink and a treatment liquid other than the pretreatment liquid, the ink, and the post-treatment liquid. The ink set for inkjet textile printing may also be an ink set consisting of the pretreatment liquid, the ink, and the post-treatment liquid. By using the ink set for inkjet textile printing in an inkjet textile printing method or in an inkjet textile printing apparatus, an image in which bleeding is sufficiently suppressed can be formed on a fabric.

[0087] [Inkjet Textile Printing Method] The inkjet textile printing method is not particularly limited as long as it is an inkjet textile printing method that forms an image on a fabric by ejecting (inkjet ejecting) the pretreatment liquid, the ink, and the posttreatment liquid provided in the inkjet textile printing ink set onto the fabric. Specific examples of the inkjet textile printing method include a method in which the pretreatment liquid, the ink, and the posttreatment liquid are sequentially ejected onto the fabric. That is, an inkjet textile printing method according to another embodiment of the present disclosure first ejects and adheres the pretreatment liquid provided in the inkjet textile printing ink set onto the fabric (pretreatment liquid ejecting step). Next, the ink provided in the inkjet textile printing ink set is ejected and adheres to the fabric to which the pretreatment liquid has been applied (ink ejecting step). Finally, the posttreatment liquid provided in the inkjet textile printing ink set is ejected and adheres to the fabric to which the ink has been applied (posttreatment liquid ejecting step). In this way, by sequentially ejecting the pre-treatment liquid, the ink, and the post-treatment liquid onto the fabric, it is possible to form an image on the fabric in which bleeding is sufficiently suppressed. The inkjet textile printing method can be carried out, for example, by an inkjet textile printing apparatus described below.

[0088] [Inkjet Textile Printing Apparatus] The inkjet textile printing apparatus is an apparatus that performs the inkjet textile printing method. The inkjet textile printing apparatus is not particularly limited as long as it can perform the pretreatment liquid ejection step, the ink ejection step, and the posttreatment liquid ejection step. Examples of the inkjet textile printing apparatus include an inkjet textile printing apparatus that forms an image on a fabric by ejecting (inkjet ejecting) the pretreatment liquid, the ink, and the posttreatment liquid provided in the inkjet textile printing ink set onto the fabric. That is, an inkjet textile printing apparatus according to another embodiment of the present disclosure includes a pretreatment liquid head that ejects and deposits the pretreatment liquid included in the inkjet textile printing ink set onto a fabric; an ink head that ejects and deposits the ink included in the inkjet textile printing ink set onto the fabric to which the pretreatment liquid has been deposited; and a posttreatment liquid head that ejects and deposits the posttreatment liquid included in the inkjet textile printing ink set onto the fabric to which the ink has been deposited. As described above, the inkjet application device can sequentially eject the pretreatment liquid, the ink, and the posttreatment liquid onto the fabric, thereby forming an image on the fabric in which bleeding is sufficiently suppressed. An example of the inkjet textile printing apparatus is the inkjet textile printing apparatus shown in FIG. 1 . Note that FIG. 1 is a schematic diagram illustrating an example of an inkjet textile printing apparatus 10 (an inkjet textile printing apparatus 10 according to another embodiment of the present disclosure) that uses the inkjet textile printing ink set according to an embodiment of the present disclosure. Furthermore, FIG. 1 shows each component diagrammatically, and the size, number, etc. of each component may be changed as appropriate.

[0089] The inkjet printing apparatus 10 ejects (inkjet ejects) the pretreatment liquid, the ink, and the posttreatment liquid included in the inkjet printing ink set onto a printing target (fabric) P.

[0090] 1, the inkjet printing apparatus 10 includes a pretreatment liquid head 5, an ink head 4, a posttreatment liquid head 6, and a mounting table 3. The ink head 4 may include a first ink head 4a, a second ink head 4b, a third ink head 4c, and a fourth ink head 4d. The pretreatment liquid head 5, the ink head 4, and the posttreatment liquid head 6 are inkjet heads.

[0091] The pretreatment liquid head 5 ejects the pretreatment liquid onto at least an image formation area of ​​the printing object P. The pretreatment liquid head 5 is not particularly limited, and examples thereof include a piezo type head and a thermal inkjet type head. The inkjet printing apparatus 10 may include one or more pretreatment liquid tanks (not shown) that contain the pretreatment liquid. In this case, the treatment liquid is supplied from the pretreatment liquid tank to the pretreatment liquid head 5.

[0092] The ink heads 4 eject ink onto an image formation area of ​​the printing object P. The first ink head 4a, second ink head 4b, third ink head 4c, and fourth ink head 4d of the ink heads 4 eject ink of different colors (e.g., yellow ink, magenta ink, cyan ink, and black ink), respectively. The number of ink heads 4 is not limited to four, and the number of ink heads 4 may be one to three, or five or more. The ink heads 4 are not particularly limited, but examples thereof include piezo-type heads and thermal inkjet-type heads. The inkjet printing device 10 may include one or more ink tanks (not shown) that store the ink, and in this case, a treatment liquid is supplied to the ink heads 4 from the ink tanks.

[0093] The post-treatment liquid head 6 ejects the post-treatment liquid onto at least an image formation area of ​​the printing object P. The post-treatment liquid head 6 is not particularly limited, but examples thereof include a piezo type head and a thermal inkjet type head. The inkjet printing apparatus 10 may include one or more post-treatment liquid tanks (not shown) that contain the post-treatment liquid. In this case, the post-treatment liquid is supplied from the post-treatment liquid tank to the post-treatment liquid head 6.

[0094] A printing object P is placed on the placement table 3. The pretreatment liquid head 5, the ink head 4, and the posttreatment liquid head 6 are disposed above the placement table 3 so that the pretreatment liquid, the ink, and the posttreatment liquid can be ejected onto the printing object P. By driving a motor (not shown), the placement table 3 moves horizontally in a direction from the pretreatment liquid head 5 toward the posttreatment liquid head 6 (for example, to the right in FIG. 1 ). The placement table 3 moves horizontally, thereby transporting the printing object P on the placement table 3.

[0095] In the inkjet printing method (production of a printed item), first, a mounting table 3 on which an object to be printed P is placed moves horizontally, and the object to be printed P is transported to a position facing the pretreatment liquid head 5. The pretreatment liquid is ejected from the pretreatment liquid head 5 onto the object to be printed P. The pretreatment liquid head 5 may eject the pretreatment liquid only onto an image formation area of ​​the object to be printed P, or onto an area wider than the image formation area of ​​the object to be printed P, or onto the entire surface of the object to be printed P. The pretreatment liquid head 5 may eject the pretreatment liquid only onto the image formation area of ​​the object to be printed P, in order to reduce the amount of pretreatment liquid used and prevent deterioration in the feel of the printed item.

[0096] After the pretreatment liquid is ejected from the pretreatment liquid head 5, the mounting table 3 on which the object to be printed P is placed further moves horizontally, and the object to be printed P is transported to a position facing the ink head 4. Then, the ink is ejected from the ink head 4 onto an image formation area of ​​the object to be printed P. In this way, an image is formed with the ink in the image formation area of ​​the object to be printed P.

[0097] After ink is ejected from the ink head 4, the mounting table 3 on which the object to be printed P is placed further moves horizontally, and the object to be printed P is transported to a position facing the posttreatment liquid head 6. The posttreatment liquid head 6 ejects the posttreatment liquid onto at least the image formation area of ​​the object to be printed P. The posttreatment liquid head 6 may eject the posttreatment liquid only onto the image formation area of ​​the object to be printed P, or onto an area wider than the image formation area of ​​the object to be printed P, or may eject the posttreatment liquid onto the entire surface of the object to be printed P. The posttreatment liquid head 6 may eject the posttreatment liquid only onto the image formation area of ​​the object to be printed P, in order to reduce the amount of posttreatment liquid used and prevent a deterioration in the feel of the printed object. In this way, a treatment film is formed by the posttreatment liquid on the image formed in the image formation area of ​​the object to be printed P.

[0098] After the post-treatment liquid is ejected from the post-treatment liquid head 6, the mounting table 3 on which the object to be printed P is placed further moves horizontally, and the object to be printed P is transported to a position facing a heating unit (not shown) that heats the object to be printed P. The heating unit heats the object to be printed P, thereby drying the pre-treatment liquid, the ink, and the post-treatment liquid. The heating temperature is not particularly limited and may be, for example, 120°C or higher and 180°C or lower, so as to be able to suitably dry the pre-treatment liquid, the ink, and the post-treatment liquid. The heating time is not particularly limited and may be, for example, 1 minute or longer and 10 minutes or shorter, so as to be able to suitably dry the pre-treatment liquid, the ink, and the post-treatment liquid. The volatile components contained in the pre-treatment liquid, the ink, and the post-treatment liquid that have been attached to the object to be printed P are dried by the heating, thereby facilitating the fixation of the pre-treatment liquid, the ink, and the post-treatment liquid to the object to be printed P. As a result, an image is formed with the ink, and a printing object P (printed item) is formed that has been treated with the pre-treatment liquid and the post-treatment liquid.

[0099] In the inkjet printing apparatus 10, for example, instead of the stage 3 moving horizontally as described above, the stage 3 may be fixed and the pretreatment liquid head 5, the ink head 4, and the posttreatment liquid head 6 may move horizontally.

[0100] Next, an inkjet recording apparatus that can use the inkjet textile printing ink set will be described in detail as an inkjet textile printing apparatus. Hereinafter, an inkjet printer equipped with an ink head that ejects ink onto a wide, long recording medium will be exemplified as a specific example of the inkjet recording apparatus. Here, this inkjet printer will be described with reference to FIGS. 2 to 4.

[0101] FIG. 2 is a perspective view showing the overall configuration of an inkjet printer 100 that can use an inkjet textile printing ink set according to an embodiment of the present disclosure. The inkjet printer 100 is a device that prints images such as letters and patterns on a fabric, which is the object of textile printing, using an inkjet method, and may be, for example, a device that performs digital textile printing. The inkjet printer may also be a device that can print various images on recording media other than the fabric, which is the object of textile printing, such as paper sheets and resin sheets. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 2. FIG. 4 is an enlarged perspective view of the carriage shown in FIG. 2.

[0102] The inkjet printer 100 is a printer that prints images on a wide and long workpiece W (recording medium) using an inkjet system. The inkjet printer 100 can also be used as a printer that forms an image on a fabric, which is the workpiece W to be printed. That is, in this embodiment, the inkjet printer 100 is used as an inkjet textile printing device. Note that in the inkjet textile printing device according to this embodiment, the recording medium is fabric, but here the recording medium is also referred to as the workpiece W. The width of the workpiece W is, for example, several meters. As shown in FIG. 2 , the inkjet printer 100 includes an apparatus frame 11 and a work transport unit 20 and a carriage 300 incorporated into this apparatus frame 11. Note that in this embodiment, the left-to-right direction is the main scanning direction S ( FIG. 4 ) when printing on the workpiece W, and the direction from rear to front is the sub-scanning direction (the transport direction F of the workpiece W, which intersects with the main scanning direction S).

[0103] The device frame 11 forms a framework for mounting various components of the inkjet printer 100. The work transport unit 20 is a mechanism that intermittently feeds (transports) the workpiece W so that the workpiece W progresses in a transport direction F from rear to front in a printing area where inkjet printing processing is performed. The carriage 300 is equipped with an ink head 4, a pre-treatment liquid head 5, a post-treatment liquid head 6, and a sub-tank 7, and moves back and forth in a main scanning direction S (left and right direction) that intersects with the transport direction F of the workpiece W during the inkjet printing processing.

[0104] The device frame 11 includes a central frame 111, a right frame 112, and a left frame 113. The central frame 111 forms a framework for mounting various components of the inkjet printer 100, and has a left-to-right width corresponding to the work transport unit 20. The right frame 112 and the left frame 113 are erected to the right and left of the central frame 111, respectively. Between the right frame 112 and the left frame 113 is the printing area 12 where printing processing is performed on the workpiece W.

[0105] The right frame 112 forms a maintenance area 13. The maintenance area 13 is an area where the carriage 300 is retracted when the printing process is not being performed. In the maintenance area 13, cleaning processes, purging processes, etc. are performed on the nozzles (ejection holes) of the ink heads 4, pre-treatment liquid heads 5, and post-treatment liquid heads 6, and caps are also fitted. The left frame 113 forms a turn-back area 14 for the carriage 300. The turn-back area 14 is an area where the carriage 300 temporarily enters when it performs a main scan in the opposite direction after performing a main scan in the opposite direction across the printing area 12 from right to left during the printing process.

[0106] A carriage guide 15 for reciprocating the carriage 300 in the left-right direction is attached to the upper side of the device frame 11. The carriage guide 15 is a flat plate-shaped member that is long in the left-right direction, and is disposed above the work transport unit 20. A timing belt 16 is attached to the carriage guide 15 so as to be able to move in a circular motion in the left-right direction (main scanning direction). The timing belt 16 is an endless belt that is driven to move in a circular motion in the left or right direction.

[0107] The carriage guide 15 is equipped with a pair of upper and lower guide rails 17 that extend parallel to the left and right and that hold the carriage 300 in a state that allows it to move back and forth in the main scanning direction S. The carriage 300 is engaged with the guide rails 17. The carriage 300 is also fixed to the timing belt 16. As the timing belt 16 moves orbitally leftward or rightward, the carriage 300 moves leftward or rightward along the carriage guide 15 while being guided by the guide rails 17.

[0108] Next, explanation will be made mainly with reference to Figure 3. The work transport unit 20 includes a feed roller 21 that pays out the work W before printing, and a take-up roller 22 that takes up the work W after printing. The feed roller 21 is located at the rear lower part of the device frame 11, and is a take-up shaft for a feed roll WA that is a roll of the work W before printing. The take-up roller 22 is located at the front lower part of the device frame 11, and is a take-up shaft for a take-up roll WB that is a roll of the work W after the printing process. A first motor M1 is attached to the take-up roller 22, which rotates the take-up roller 22 about its axis and performs the operation of winding up the work W.

[0109] The path between the delivery roller 21 and the take-up roller 22 and passing through the printing area 12 is the transport path for the workpiece W. Arranged on this transport path, in order from upstream, are a first tension roller 23, a work guide 24, a transport roller 25 and a pinch roller 26, a turn-back roller 27, and a second tension roller 28. The first tension roller 23 applies a predetermined tension to the workpiece W on the upstream side of the transport roller 25. The work guide 24 changes the transport direction of the workpiece W from upward to forward, allowing the workpiece W to enter the printing area 12.

[0110] The transport roller 25 is a roller that generates a transport force that intermittently feeds the workpiece W in the printing area 12. The transport roller 25 is driven to rotate around its axis by the second motor M2, and intermittently transports the workpiece W forward (in a predetermined transport direction F) so that the workpiece W passes through the printing area 12 (image forming position) facing the carriage 300. The pinch roller 26 is disposed opposite the transport roller 25 from above, and forms a transport nip portion with the transport roller 25.

[0111] The turn-back roller 27 changes the transport direction of the workpiece W that has passed through the printing area 12 from forward to downward, and guides the workpiece W after printing processing to the take-up roller 22. The second tension roller 28 applies a predetermined tension to the workpiece W downstream of the transport roller 25. A platen 29 is disposed below the transport path of the workpiece W in the printing area 12.

[0112] The carriage 300 is cantilevered on the guide rail 17 and moves back and forth in a main scanning direction S (left and right direction in FIGS. 2 and 3 ) that intersects with the transport direction F (orthogonal in FIGS. 2 and 3 ). The carriage 300 includes a carriage frame 30, and an ink head 4, a pre-treatment liquid head 5, a post-treatment liquid head 6, and a sub-tank 7 ( FIG. 4 ) that are mounted on the carriage frame 30. The carriage frame 30 includes a head support frame 31 and a back frame 32.

[0113] The head support frame 31 is a horizontal plate that holds the ink heads 4, the pre-treatment liquid heads 5, and the post-treatment liquid heads 6. The back frame 32 is a vertical plate that extends upward from the rear end edge of the head support frame 31. As described above, the timing belt 16 is fixed to the back frame 32. Furthermore, the guide rails 17 are engaged with the back frame 32. That is, in the example shown in Fig. 3, the back frame 32 is an engaging portion that holds the back frame 32 in a cantilevered state on the guide rails 17. The head support frame 31 is a horizontal plate whose rear end side is supported in a cantilevered state on the guide rails 17 by the engaging portion.

[0114] The cantilevered state refers to a state in which the engagement portion (back frame 32), which is a portion of the carriage 300 that is held by the guide rail 17, which is a holding member, is present only on one side, either upstream or downstream, from the center of the carriage 300 in the transport direction F, and no other engagement portion is present on the side opposite to the side where the engagement portion is present. The engagement portion may also be located outside the range in which the ink heads 4, pretreatment liquid heads 5, and posttreatment liquid heads 6 are arranged in the transport direction F. In other words, the engagement portion may be located only on the upstream side or only on the downstream side of the range in which the ink heads 4, pretreatment liquid heads 5, and posttreatment liquid heads 6 are arranged in the transport direction F.

[0115] The carriage 300 will now be further described. Fig. 4 is an enlarged perspective view of the carriage 300 shown in Fig. 2. Fig. 4 shows the transport direction F (sub-scanning direction) of the workpiece W and the main scanning direction S, which is the direction of movement of the carriage 300. Fig. 4 shows an example in which the carriage 300 is equipped with a plurality of ink heads 4 that eject ink for image formation onto the workpiece W, a pre-treatment liquid head 5 and a post-treatment liquid head 6 that eject non-color-forming treatment liquid, and a plurality of sub-tanks 7 that supply the ink, treatment liquid, and post-treatment liquid to these heads 4 to 6.

[0116] Each ink head 4 has a number of nozzles (ink ejection holes) that eject ink droplets using an ejection method such as a piezoelectric method using a piezoelectric element or a thermal method using a heating element, and ink passages that guide ink to the nozzles. For example, the inks described above can be used. In the example shown in FIG. 4, the multiple ink heads 4 are capable of ejecting eight colors of ink. The ink heads 4 are mounted on the head support frame 31 of the carriage 300 so as to be aligned in two rows in the main scanning direction S. Each color ink head 4 has two heads.

[0117] In the example shown in FIG. 4 , the ink heads 4 specifically include a first upstream ink head 41A and a first downstream ink head 41B. These ink heads 4 eject, for example, yellow ink. The ink heads 4 also include a second upstream ink head 42A and a second downstream ink head 42B. These ink heads 4 eject, for example, magenta ink. Similarly, as shown in FIG. 4 , two ink heads 4 ejecting ink of the same color are arranged at positions offset from each other in the transport direction F and the main scanning direction S. These two ink heads 4 form a set, resulting in a total of eight sets of ink heads 4 (the first upstream ink head 41A to the eighth upstream ink head 48A, and the first downstream ink head 41B to the eighth downstream ink head 48B) that eject inks of different colors. The inks included in the inkjet textile printing ink set can be used.

[0118] The pre-treatment liquid head 5 and the post-treatment liquid head 6 are disposed at positions different from the ink heads 4 in the transport direction F. The pre-treatment liquid head 5 is disposed upstream of the ink heads 4 in the transport direction F. FIG. 4 shows an example in which one pre-treatment liquid head 5 is disposed near the left end of the array of ink heads 4. Similarly, the post-treatment liquid head 6 is disposed downstream of the ink heads 4 in the transport direction F. FIG. 4 shows an example in which one post-treatment liquid head 6 is disposed at the right end of the array of ink heads 4. In other examples of inkjet recording devices, for example, a plurality of pre-treatment liquid heads 5 or a plurality of post-treatment liquid heads 6 may be disposed.

[0119] A series of heads along the main scanning direction S, which are made up of the ink heads 4, pretreatment liquid heads 5, and posttreatment liquid heads 6, will be referred to as a row of heads, or simply as a row. Also, a series of heads along the transport direction F, which are made up of the ink heads 4, pretreatment liquid heads 5, and posttreatment liquid heads 6, will be referred to as a row of heads, or simply as a row.

[0120] The pretreatment liquid head 5 ejects a pretreatment liquid for performing a predetermined pretreatment on the workpiece W. The pretreatment liquid is ejected from the pretreatment liquid head 5 onto a position on the workpiece W where ink has not yet been ejected from the ink head 4. As the pretreatment liquid, the pretreatment liquid provided in the ink set for inkjet textile printing can be used.

[0121] The post-treatment liquid head 6 ejects a post-treatment liquid for performing a predetermined post-treatment on the workpiece W to which the ink has adhered. The post-treatment liquid is ejected from the post-treatment liquid head 6 to the position of the workpiece W after the ink has been ejected from the ink head 4. As the post-treatment liquid, the post-treatment liquid provided in the ink set for inkjet textile printing can be used.

[0122] Here, a non-color-forming treatment liquid refers to a treatment liquid that, when printed alone on a recording medium, is not perceived as having a color by the naked eye. Colors here include colors with a saturation of zero, such as black, white, and gray. A non-color-forming treatment liquid is essentially a transparent liquid; however, when viewed in its liquid state, for example, 1 liter of treatment liquid may not be completely transparent, but may appear slightly white. Such colors are so faint that, when printed alone on a recording medium, they are not perceived as having a color by the naked eye. Note that, depending on the type of treatment liquid, when printed alone on a recording medium, changes such as gloss may appear on the recording medium, but such a state is not considered color-forming.

[0123] In the inkjet printer 100, by using the ink, pre-treatment liquid, and post-treatment liquid provided in the inkjet textile printing ink set, even when fabric is used as the recording medium, it is possible to form an image on the fabric in which bleeding is sufficiently suppressed.

[0124] 2 to 4, the pretreatment liquid and the posttreatment liquid may be ejected onto substantially the entire surface of the workpiece W, or the pretreatment liquid and the posttreatment liquid may be selectively ejected in accordance with the image to be printed, similar to ink. Furthermore, the pretreatment liquid, the ink, and the posttreatment liquid are ejected in this order onto the portion of the workpiece W where a color is to be printed in accordance with the image. In this case, the ink may be of one color or multiple colors. Basically, the pretreatment liquid and the posttreatment liquid are not ejected onto the portion where no color is to be printed, i.e., the portion where no ink is ejected.

[0125] 4, openings 31H are provided in the head support frame 31 at positions where the heads are arranged. The ink heads 4, the pre-treatment liquid heads 5, and the post-treatment liquid heads 6 are attached to the head support frame 31 so as to be fitted into the respective openings 31H. Nozzles arranged on the lower end surfaces of the heads (ink heads 4, pre-treatment liquid heads 5, and post-treatment liquid heads 6) are exposed from the respective openings 31H.

[0126] The plurality of sub-tanks 7 are supported by the carriage 300 above the respective heads (ink head 4, pre-treatment liquid head 5, and post-treatment liquid head 6) via a holding frame (not shown). The plurality of sub-tanks 7 are provided corresponding to each of the ink heads 4, pre-treatment liquid heads 5, and post-treatment liquid heads 6. The ink, pre-treatment liquid, or post-treatment liquid is supplied to each sub-tank 7 from a main tank 90 (described below) that contains the ink, pre-treatment liquid, or post-treatment liquid, and these are supplied to each of the heads 4, 5, and 6. The sub-tanks 7 and the respective heads 4, 5, and 6 are connected by conduits (not shown in FIG. 4 ).

[0127] 4, the subtanks 7 specifically include a first supply subtank 71A to an eighth supply subtank 78A, a pre-processing supply subtank 7FA, and a post-processing supply subtank 7RA, which are arranged on the rear side along the main scanning direction S. Furthermore, the subtanks 7 further include a first recovery subtank 71B to an eighth recovery subtank 78B, a pre-processing recovery subtank 7FB, and a post-processing recovery subtank 7RB, which are arranged on the front side along the main scanning direction S.

[0128] The first supply subtank 71A and the first recovery subtank 71B located at the leftmost side of the carriage 300 store, for example, yellow ink containing a pigment. In this case, the first supply subtank 71A supplies yellow ink to the first upstream ink head 41A and the first downstream ink head 41B (both referred to as supply destinations). Meanwhile, the first recovery subtank 71B stores yellow ink recovered from the first upstream ink head 41A and the first downstream ink head 41B. As described above, a portion of the yellow ink is ejected toward the workpiece W from the first upstream ink head 41A and the first downstream ink head 41B. Similarly, the second supply subtank 72A supplies magenta ink to, for example, the second upstream ink head 42A and the second downstream ink head 42B. Meanwhile, the second recovery subtank 72B stores magenta ink recovered from the second upstream ink head 42A and the second downstream ink head 42B. The other sub-tanks, from the third sub-tank to the eighth sub-tank, also have the same structure and function as those described above.

[0129] The pre-treatment supply sub-tank 7FA supplies the pre-treatment liquid to the pre-treatment liquid head 5, and the pre-treatment recovery sub-tank 7FB recovers the pre-treatment liquid from the pre-treatment liquid head 5. The post-treatment supply sub-tank 7RA supplies the post-treatment liquid to the post-treatment liquid head 6, and the post-treatment recovery sub-tank 7RB recovers the post-treatment liquid from the post-treatment liquid head 6.

[0130] As described above, the inkjet printer 100 is an all-in-one printer in which three types of heads - the ink head 4, the pre-treatment liquid head 5, and the post-treatment liquid head 6 - are mounted on a single carriage 300. With this inkjet printer 100, for example, in the printing process of performing inkjet printing on fabric in digital textile printing, the pre-treatment liquid ejection process and the post-treatment liquid ejection process can be executed integrally. This makes it possible to simplify the textile printing process and make the textile printing device more compact.

[0131] The inkjet printer 100 uses a serial printing method to perform printing on the workpiece W. Specifically, if the workpiece W is wide, it is not possible to print while continuously feeding the workpiece W. The serial printing method is a printing method in which a carriage 300 carrying ink heads 4 of each color moves back and forth in the main scanning direction S, and the workpiece W is intermittently fed in the transport direction F, repeatedly.

[0132] In the inkjet printer 100, a band-shaped image is printed while the carriage 300 moves in the forward direction, which is one of the main scanning directions S. During this main scanning in the forward direction, the feeding of the workpiece W is stopped. After printing the band-shaped image, the workpiece W is sent out in the transport direction F by a predetermined pitch. At this time, the carriage 300 waits in the turn-back area 14 on the left end side. After sending out the workpiece W, the carriage 300 turns back in the return direction, which is opposite to the forward direction, as the timing belt 16 moves in reverse. The workpiece W is in a stationary state. Then, while moving in the return direction, the carriage 300 prints the next band-shaped image upstream of the previous band-shaped image. Similar operations are repeated thereafter.

[0133] As described above, this specification discloses various aspects of the technology, the main technologies of which are summarized below.

[0134] An inkjet textile printing ink set according to a first aspect includes a pre-treatment liquid, an ink, and a post-treatment liquid, wherein the static surface tension of the pre-treatment liquid is higher than the static surface tension of both the ink and the post-treatment liquid.

[0135] The ink set for inkjet textile printing according to a second aspect is the ink set for inkjet textile printing according to the first aspect, wherein a difference between the static surface tension of the pretreatment liquid and the static surface tension of the ink is 0.5 mN / m or more and 5.5 mN / m or less.

[0136] The ink set for inkjet textile printing according to a third aspect is the ink set for inkjet textile printing according to the first or second aspect, wherein a difference in static surface tension between the pre-treatment liquid and the post-treatment liquid is 1 mN / m or more and 10 mN / m or less.

[0137] The ink set for inkjet textile printing according to a fourth aspect is the ink set for inkjet textile printing according to any one of the first to third aspects, wherein a difference between a static surface tension of the ink and a static surface tension of the post-treatment liquid is 0 mN / m or more and 5 mN / m or less.

[0138] The ink set for inkjet textile printing according to a fifth aspect is the ink set for inkjet textile printing according to any one of the first to fourth aspects, wherein the static surface tension of the ink is higher than the static surface tension of the post-treatment liquid.

[0139] An ink set for inkjet textile printing according to a sixth aspect is the ink set for inkjet textile printing according to any one of the first to fifth aspects, wherein the pretreatment liquid contains a nonionic surfactant.

[0140] An ink jet printing ink set according to a seventh aspect is the ink jet printing ink set according to the sixth aspect, wherein the nonionic surfactant is at least one of an acetylene glycol-based surfactant and a silicone-based surfactant.

[0141] An ink set for inkjet textile printing according to an eighth aspect is the ink set for inkjet textile printing according to the fifth or sixth aspect, wherein the content of the nonionic surfactant is 0.1% by mass or more and 5% by mass or less with respect to the total amount of the pretreatment liquid.

[0142] An inkjet textile printing method according to a ninth aspect includes applying the pretreatment liquid provided in the inkjet textile printing ink set according to any one of the first to eighth aspects to an object to be printed, applying the ink provided in the inkjet textile printing ink set to the object to be printed to which the pretreatment liquid has been applied, and applying the post-treatment liquid provided in the inkjet textile printing ink set to the object to be printed to which the ink has been applied.

[0143] An inkjet textile printing apparatus according to a tenth aspect includes a pretreatment liquid head that applies the pretreatment liquid provided in the inkjet textile printing ink set according to any one of the first to eighth aspects to a printing object, an ink head that applies the ink provided in the inkjet textile printing ink set to the printing object to which the pretreatment liquid has been applied, and a posttreatment liquid head that applies the posttreatment liquid provided in the inkjet textile printing ink set to the printing object to which the ink has been applied.

[0144] According to the present invention, it is possible to provide an ink set for inkjet textile printing, an inkjet textile printing method, and an inkjet textile printing apparatus that are capable of forming an image on a fabric in which bleeding is sufficiently suppressed.

[0145] The present disclosure will be explained in more detail below using examples, but the present disclosure is not limited to these examples in any way.

[0146] Examples 1 to 11 and Comparative Examples 1 to 4 First, the pre-treatment liquid, ink, and post-treatment liquid used in the ink set for inkjet textile printing in the examples and comparative examples will be described.

[0147] (Preparation of Pretreatment Liquid) Pretreatment Liquid 1 3 parts by mass (solids content) of a water-soluble cationic polymer as a cationic compound (diallyldimethylammonium chloride-sulfur dioxide copolymer, PAS-A-5 manufactured by Nittobo Medical Co., Ltd., weight average molecular weight Mw 4000), 1 part by mass of a nonionic surfactant (acetylene glycol ethylene oxide adduct, Surfynol 440 manufactured by Nissin Chemical Industry Co., Ltd.), 30 parts by mass of propylene glycol, and the remainder of the mixture was mixed and then filtered through a 5 μm filter to obtain pretreatment liquid 1. That is, the formulation of pretreatment liquid 1 was 3% by mass of the cationic compound, 1% by mass of the nonionic surfactant, 30% by mass of propylene glycol, and the remainder of the mixture was water.

[0148] The static surface tension of this pretreatment liquid 1 (static surface tension at 25°C) was measured by the Wilhelmy method using an automatic surface tensiometer (DY-300 manufactured by Kyowa Interface Science Co., Ltd.) at a measurement temperature of 25°C, and was found to be 33.5 mN / m.

[0149] Pre-treatment liquid 2 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 0.95 parts by mass (0.95% by mass).

[0150] The static surface tension of this pretreatment liquid 2 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 34.0 mN / m.

[0151] Pre-treatment liquid 3

[0123] Pre-treatment liquid 3 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 1.1 parts by mass (1.1% by mass).

[0152] The static surface tension of this pretreatment liquid 3 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 32.0 mN / m.

[0153] Pre-treatment liquid 4 Pre-treatment liquid 4 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 0.85 parts by mass (0.85% by mass).

[0154] The static surface tension of this pretreatment liquid 4 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 36.5 mN / m.

[0155] Pre-treatment liquid 5 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 0.7 parts by mass (0.7% by mass).

[0156] The static surface tension (static surface tension at 25° C.) of this pretreatment liquid 5 was measured by the above-mentioned method and was found to be 40.0 mN / m.

[0157] Pre-treatment liquid 6

[0123] Pre-treatment liquid 6 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 0.8 parts by mass (0.8% by mass).

[0158] The static surface tension of this pretreatment liquid 6 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 37.0 mN / m.

[0159] Pre-treatment liquid 7 Pre-treatment liquid 7 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 1.4 parts by mass (1.4% by mass).

[0160] The static surface tension of this pretreatment liquid 7 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 29.5 mN / m.

[0161] Pre-treatment liquid 8 Pre-treatment liquid 8 was obtained in the same manner as pre-treatment liquid 1, except that the content of the nonionic surfactant was changed from 1 part by mass (1% by mass) to 1.6 parts by mass (1.6% by mass).

[0162] The static surface tension of this pretreatment liquid 8 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 27.5 mN / m.

[0163] Pre-treatment liquid 9 Pre-treatment liquid 9 was obtained in the same manner as pre-treatment liquid 1, except that 0.05 parts by mass (0.05% by mass) of a silicone surfactant (polyether-modified silicone, Silface SAG002 manufactured by Nissin Chemical Industry Co., Ltd.), which is another nonionic surfactant, was used in place of 1 part by mass (1% by mass) of the nonionic surfactant (acetylene glycol ethylene oxide adduct, Surfynol 440 manufactured by Nissin Chemical Industry Co., Ltd.).

[0164] The static surface tension of this pretreatment liquid 9 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 33.5 mN / m.

[0165] Pre-treatment liquid 10

[0123] Pre-treatment liquid 10 was obtained in the same manner as pre-treatment liquid 9, except that the content of the silicone surfactant was changed from 0.05 parts by mass (0.05% by mass) to 0.07 parts by mass (0.07% by mass).

[0166] The static surface tension of this pretreatment liquid 10 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 32.0 mN / m.

[0167] (Preparation of Inks) Ink 1 Ink 1 was prepared by mixing 4 parts by mass (solids content) of an anionic pigment dispersion (AE-2078F, C.I. Pigment Black manufactured by Sanyo Dish Co., Ltd.) having a pigment concentration of 20% by mass, 8 parts by mass (solids content) of a urethane dispersion (Superflex 470 manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) having a solids content of 38% by mass, 0.9 parts by mass of a nonionic surfactant (acetylene glycol ethylene oxide adduct, Surfynol 440 manufactured by Nissin Chemical Industry Co., Ltd.), 30 parts by mass of propylene glycol, and the remainder of the mixture being water, followed by filtering through a 5 μm filter. In other words, the formulation of Ink 1 was 4% by mass of pigment, 8% by mass of binder resin particles, 0.9% by mass of nonionic surfactant, 30% by mass of propylene glycol, and the remainder being water.

[0168] The static surface tension of this ink 1 (static surface tension at 25° C.) was measured by the above method and was found to be 32.0 mN / m.

[0169] Ink 2 Ink 2 was obtained in the same manner as Ink 1, except that the content of the nonionic surfactant was changed from 0.9 parts by mass (0.9% by mass) to 1.25 parts by mass (1.25% by mass).

[0170] The static surface tension of this ink 2 (static surface tension at 25° C.) was measured by the above method and was found to be 29.0 mN / m.

[0171] Ink 3 Ink 3 was obtained in the same manner as Ink 1, except that the content of the nonionic surfactant was changed from 0.9 parts by mass (0.9% by mass) to 1.05 parts by mass (1.05% by mass).

[0172] The static surface tension of this ink 3 (static surface tension at 25° C.) was measured by the above method and was found to be 31.5 mN / m.

[0173] Ink 4 Ink 4 was obtained in the same manner as Ink 1, except that the content of the nonionic surfactant was changed from 0.9 parts by mass (0.9% by mass) to 0.7 parts by mass (0.7% by mass).

[0174] The static surface tension of this ink 4 (static surface tension at 25° C.) was measured by the above method and was found to be 34.5 mN / m.

[0175] Ink 5 Ink 5 was obtained in the same manner as Ink 1, except that the content of the nonionic surfactant was changed from 0.9 parts by mass (0.9% by mass) to 1.4 parts by mass (1.4% by mass).

[0176] The static surface tension of this ink 5 (static surface tension at 25° C.) was measured by the above method and was found to be 28.0 mN / m.

[0177] Ink 6 Ink 6 was obtained in the same manner as Ink 1, except that the content of the nonionic surfactant was changed from 0.9 parts by mass (0.9% by mass) to 0.8 parts by mass (0.8% by mass).

[0178] The static surface tension of this ink 6 (static surface tension at 25° C.) was measured by the above method and was found to be 34.0 mN / m.

[0179] Ink 7 Ink 7 was obtained in the same manner as Ink 1, except that 0.06 parts by mass (0.06% by mass) of a silicone surfactant (polyether-modified silicone, Silface SAG002 manufactured by Nissin Chemical Industry Co., Ltd.), which is another nonionic surfactant, was used in place of 0.9 parts by mass (0.9% by mass) of the nonionic surfactant (acetylene glycol ethylene oxide adduct, Surfynol 440 manufactured by Nissin Chemical Industry Co., Ltd.).

[0180] The static surface tension of this ink 7 (static surface tension at 25° C.) was measured by the above method and was found to be 32.0 mN / m.

[0181] Ink 8 Ink 8 was obtained in the same manner as Ink 7, except that the content of the silicone surfactant was changed from 0.06 parts by mass (0.06% by mass) to 0.05 parts by mass (0.05% by mass).

[0182] The static surface tension of this ink 8 (static surface tension at 25° C.) was measured by the above method and was found to be 34.0 mN / m.

[0183] (Preparation of Post-Treatment Liquid) Post-Treatment Liquid 1 10 parts by mass (solids content) of a silicone oil emulsion (POLON-MF-51 manufactured by Shin-Etsu Chemical Co., Ltd.) with a silicone oil content of 39% by mass, 30 parts by mass of propylene glycol, and the remainder of the water were mixed, and then filtered through a 5 μm filter to obtain post-treatment liquid 1. That is, the formulation of post-treatment liquid 1 was 10% by mass of silicone oil emulsion, 30% by mass of propylene glycol, and the remainder of the water.

[0184] The static surface tension (static surface tension at 25° C.) of this post-treatment liquid 1 was measured by the above-mentioned method and was found to be 31.0 mN / m.

[0185] Post-treatment liquid 2: 10 parts by mass (solids content) of a silicone oil emulsion (POLON-MF-51 manufactured by Shin-Etsu Chemical Co., Ltd.) having a silicone oil content of 39% by mass, 0.4 parts by mass of a nonionic surfactant (acetylene glycol ethylene oxide adduct, Surfynol 440 manufactured by Nissin Chemical Industry Co., Ltd.), 30 parts by mass of propylene glycol, and the remainder of the water were mixed and then filtered through a 5 μm filter to obtain post-treatment liquid 2. That is, the formulation of post-treatment liquid 2 was 10% by mass of the silicone oil emulsion, 0.4% by mass of the nonionic surfactant, 30% by mass of propylene glycol, and the remainder of the water.

[0186] The static surface tension of this post-treatment liquid 2 (static surface tension at 25° C.) was measured by the above-mentioned method and was found to be 29.0 mN / m.

[0187] Post-treatment liquid 3 Post-treatment liquid 3 was obtained in the same manner as post-treatment liquid 2, except that the content of the nonionic surfactant was changed from 0.4 parts by mass (0.4% by mass) to 0.6 parts by mass (0.6% by mass).

[0188] The static surface tension (static surface tension at 25° C.) of this post-treatment liquid 3 was measured by the above-mentioned method and was found to be 28.0 mN / m.

[0189] Post-treatment liquid 4 Post-treatment liquid 4 was obtained in the same manner as post-treatment liquid 2, except that the content of the nonionic surfactant was changed from 0.4 parts by mass (0.4% by mass) to 1.1 parts by mass (1.1% by mass).

[0190] The static surface tension (static surface tension at 25° C.) of this post-treatment liquid 4 was measured by the above-mentioned method and was found to be 24.0 mN / m.

[0191] Post-treatment liquid 5 Post-treatment liquid 5 was obtained in the same manner as post-treatment liquid 2, except that the content of the nonionic surfactant was changed from 0.4 parts by mass (0.4% by mass) to 0.2 parts by mass (0.2% by mass).

[0192] The static surface tension (static surface tension at 25° C.) of this post-treatment liquid 5 was measured by the above-mentioned method and was found to be 30.0 mN / m.

[0193] Post-treatment liquid 6 Post-treatment liquid 6 was obtained in the same manner as post-treatment liquid 2, except that 0.05 parts by mass (0.05% by mass) of a silicone surfactant (polyether-modified silicone, Silface SAG002 manufactured by Nissin Chemical Industry Co., Ltd.), which is another nonionic surfactant, was used in place of 0.4 parts by mass (0.4% by mass) of the nonionic surfactant (acetylene glycol ethylene oxide adduct, Surfynol 440 manufactured by Nissin Chemical Industry Co., Ltd.).

[0194] The static surface tension (static surface tension at 25° C.) of this post-treatment liquid 6 was measured by the above-mentioned method and was found to be 30.0 mN / m.

[0195] Example 1 In inkjet printing, polyester tropical fabric (manufactured by Shikisen Co., Ltd.) was used as the fabric to be printed. To produce printed textiles for evaluation, a flatbed printing jig (a flatbed inkjet recording device corresponding to FIG. 1 , equipped with the inkjet heads, a prototype machine manufactured by Kyocera Corporation) was used, in which inkjet heads (KJ4B manufactured by Kyocera Corporation) were arranged in the transport direction. The first inkjet head (downstream in the transport direction) was filled with the pretreatment liquid 1. The second inkjet head was filled with the ink 1. The third inkjet head (upstream in the transport direction) was filled with the posttreatment liquid 1. Using this flatbed printing jig, the pretreatment liquid, the ink, and the posttreatment liquid were each ejected at a rate of 10 g / m. ２ , 20 g / m ２ , and 5 g / m ２ The ink was ejected from each head onto a polyester tropical fabric so that the ink was uniformly distributed over the entire surface. The inkjet printing conditions were a distance of 3 mm between the fabric and the inkjet head, and an inkjet head temperature of 25°C. Next, the object to be printed onto which the pretreatment liquid, ink, and post-treatment liquid had been ejected was heated in an oven at 160°C for 3 minutes. This dried the pretreatment liquid, ink, and post-treatment liquid ejected onto the object to be printed, and a printed item according to Example 1 was obtained.

[0196] Example 2 A printed item according to Example 2 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 2, the ink 2, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0197] Example 3 A printed item according to Example 3 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 3, the ink 3, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0198] Example 4 A printed item according to Example 4 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 4, the ink 1, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0199] Example 5 A printed item according to Example 5 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 5, the ink 4, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0200] Example 6 A printed item according to Example 6 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 1, the ink 3, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0201] Example 7 A printed item according to Example 7 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 1, the ink 1, and the post-treatment liquid 2 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0202] Example 8 A printed material according to Example 8 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 6, the ink 1, and the post-treatment liquid 3 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0203] Example 9 A printed item according to Example 9 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 2, the ink 2, and the post-treatment liquid 4 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0204] Example 10 A printed item according to Example 10 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 1, the ink 5, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0205] Example 11 A printed item according to Example 11 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 9, the ink 7, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0206] Comparative Example 1 A printed material according to Comparative Example 1 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 3, the ink 6, and the post-treatment liquid 5 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0207] Comparative Example 2 A printed material according to Comparative Example 2 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 7, the ink 5, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0208] Comparative Example 3 A printed material according to Comparative Example 3 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 8, the ink 2, and the post-treatment liquid 1 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0209] Comparative Example 4 A printed material according to Comparative Example 4 was obtained in the same manner as in Example 1, except that the pre-treatment liquid 10, the ink 8, and the post-treatment liquid 6 were used as the pre-treatment liquid, the ink, and the post-treatment liquid.

[0210] The printed textiles obtained as described above were evaluated by the following methods.

[0211] [Evaluation of bleeding] The obtained printed textile was visually inspected and evaluated according to the following criteria. If no bleeding was observed and it was judged to be a clear image, it was rated as "5." If slight bleeding was observed but it was judged to be a clear image, it was rated as "4." If some bleeding was observed but it was judged to be an image with no practical problems, it was rated as "3." If bleeding was observed and it was judged to be an unclear image, it was rated as "2." If significant bleeding was observed, it was rated as "1." In this evaluation, as described above, the smaller the number, the worse the evaluation (for example, "5" is the best and "1" is the worst), and "3" to "5" were judged to be pass, and "1" and "2" were judged to be fail.

[0212] The results are shown together with the combinations of pre-treatment liquid, ink, and post-treatment liquid.

[0213] As shown in Table 1, it was found that when ink sets were used that combined pre-treatment liquid, ink, and post-treatment liquid such that the above relationships (Spre>Si and Spre>Spost) were satisfied (Examples 1 to 11), bleeding of images formed on fabric was suppressed compared to when this relationship was not satisfied (Comparative Examples 1 to 4). Furthermore, it was found that when ink sets were used that combined pre-treatment liquid, ink, and post-treatment liquid such that the above relationships (Spre>Si and Spre>Spost) and Si>Spost were satisfied (Example 1, Examples 3 to 9, and Example 11), bleeding of images formed was less likely to occur compared to when Si>Spost was not satisfied (Example 2 and Example 9).

[0214] This application is based on Japanese Patent Application No. 2023-092877 filed on June 6, 2023, the contents of which are incorporated herein by reference.

[0215] In order to express the present invention, the present invention has been properly and sufficiently described through the embodiments in the above, but it should be recognized that those skilled in the art can easily change and / or improve the above-mentioned embodiments. Therefore, unless the changes or improvements made by those skilled in the art are at a level that causes departure from the scope of the claims described in the claims, such changes or improvements are interpreted as being included in the scope of the claims.

[0216] According to the present invention, there are provided an ink set for inkjet textile printing, an inkjet textile printing method, and an inkjet textile printing apparatus that are capable of forming an image on a fabric in which bleeding is sufficiently suppressed.

[0217] DESCRIPTION OF SYMBOLS 3 Mounting table 4 Ink head 4a First ink head 4b Second ink head 4c Third ink head 4d Fourth ink head 5 Pre-treatment liquid head 6 Post-treatment liquid head 10 Inkjet textile printing device 11 Device frame 12 Printing area 13 Maintenance area 14 Turn-back area 15 Carriage guide 16 Timing belt 17 Guide rail 20 Work transport section 21 Feed roller 22 Take-up roller 23 First tension roller 24 Work guide 25 Transport roller 26 Pinch roller 27 Turn-back roller 28 Second tension roller 29 Platen 30 Carriage frame 31 Head support frame 32 Back frame 41A to 48A First to eighth upstream ink heads 41B to 48B First to eighth downstream ink heads 7 Sub-tank 7FA Pre-treatment supply sub-tank 7FB Pre-treatment recovery sub-tank 7RA Post-treatment supply sub-tank 7RB Post-treatment recovery sub-tank 71A-78A 1st to 8th supply sub-tanks 71B-78B 1st to 8th recovery sub-tanks 90 Main tank 100 Inkjet printer 111 Center frame 112 Right frame 113 Left frame 300 Carriage F Transport direction M1 First motor M2 Second motor P Printing object S Main scanning direction W Work WA Delivery roll WB Take-up roll

Claims

1. A pretreatment liquid, an ink, and a non-color-forming posttreatment liquid are provided, The ink set for inkjet textile printing, wherein the static surface tension of the pre-treatment liquid is higher than the static surface tension of both the ink and the post-treatment liquid.

2. 2. The ink set for ink-jet textile printing according to claim 1, wherein a difference between the static surface tension of the pretreatment liquid and the static surface tension of the ink is 0.5 mN / m or more and 5.5 mN / m or less.

3. 2. The ink set for ink-jet textile printing according to claim 1, wherein a difference between the static surface tension of the pre-treatment liquid and the static surface tension of the post-treatment liquid is 1 mN / m or more and 10 mN / m or less.

4. 2. The ink set for ink-jet textile printing according to claim 1, wherein a difference between a static surface tension of the ink and a static surface tension of the post-treatment liquid is 0 mN / m or more and 5 mN / m or less.

5. The ink set for ink-jet textile printing according to claim 1 , wherein the static surface tension of the inks is higher than the static surface tension of the post-treatment liquid.

6. The ink set for ink-jet textile printing according to claim 1 , wherein the pretreatment liquid contains a nonionic surfactant.

7. The ink set for ink-jet printing according to claim 6, wherein the nonionic surfactant is at least one of an acetylene glycol surfactant and a silicone surfactant.

8. The ink set for inkjet textile printing according to claim 6, wherein a content of the nonionic surfactant is 0.1% by mass or more and 5% by mass or less with respect to the total amount of the pretreatment liquid.

9. The pretreatment liquid provided in the ink set for ink-jet textile printing according to any one of claims 1 to 8 is ejected onto a fabric and adhered to the fabric, ejecting and depositing the inks included in the inkjet printing ink set onto the fabric to which the pretreatment liquid has been deposited; an inkjet textile printing method, wherein the post-treatment liquid provided in the inkjet textile printing ink set is ejected onto the fabric to which the ink has been applied.

10. a pretreatment liquid head provided in the ink set for ink-jet textile printing according to any one of claims 1 to 8, which ejects and deposits the pretreatment liquid onto a fabric; an ink head that ejects and deposits the ink included in the ink set for ink jet textile printing onto the fabric to which the pretreatment liquid has been deposited; an inkjet textile printing apparatus comprising: a post-treatment liquid head that ejects and deposits the post-treatment liquid provided in the ink set for ink jet textile printing onto the fabric to which the ink has been deposited.