Printing method

Abstract

To provide a printing method that combines a color development property and washing fastness.SOLUTION: A printing method of the present invention is a printing method for dyeing a fabric, the fabric containing natural fibers and synthetic cellulose fibers, the printing method comprises: imparting a pretreatment liquid containing a solvent in which a value of a ratio (I / O value) of an inorganic value and an organic value is 3.0 or less and an aromatic heterocyclic compound to the fabric; imparting a sublimation colorant to the fabric; and imparting an aftertreatment liquid containing water to the fabric, in this order.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a textile printing method. More specifically, this invention relates to a textile printing method that achieves both color development and wash fastness. [Background technology]

[0002] Conventionally, a textile printing method is known in which textiles are dyed using a printing ink containing a sublimation colorant (see Patent Documents 1 and 2). Furthermore, in textile printing, it is known that using a solvent with high hydrophobicity that easily dissolves the sublimation colorant into a single molecule state is beneficial for improving color development. However, when a highly hydrophobic solvent is used to pre-treat the textile, the sublimation colorant tends to remain in a single molecule state within the textile, which tends to worsen wash fastness. Specifically, the sublimation colorant is more likely to leach out of the textile during washing, leading to color fading and contamination of other items being washed together. In particular, when using textiles containing fibers that swell easily in water (e.g., natural fibers, synthetic cellulose fibers), the leaching of the sublimation colorant from the textile is more likely to occur, resulting in even worse wash fastness. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-042514 [Patent Document 2] Chinese Patent No. 110130129 Specification [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] This invention has been made in view of the above-mentioned problems and circumstances. The problem to be solved by this invention is to provide a printing method that achieves both color development and wash fastness. [Means for solving the problem]

[0005] The problem described in the present invention is solved by the following means.

[0006] 1. A printing method for dyeing a fabric, wherein: the fabric contains natural fibers or synthetic cellulose fibers; the method comprises the following steps in order: a step of applying a pretreatment liquid containing a solvent having a ratio of inorganic value to organic value (I / O value) of 3.0 or less and an aromatic heterocyclic compound to the fabric; a step of applying a sublimation coloring material to the fabric; and a step of applying a post-treatment liquid containing water to the fabric, a step of applying a sublimation coloring material to the fabric; and a step of applying a post-treatment liquid containing water to the fabric, which are performed in this order, wherein the aromatic heterocyclic compound has a structure represented by the following general formula (1) A printing method characterized by the above.

Chemical Formula

[0007] 2. The printing method according to claim 1, wherein the solvent contains dimethyl sulfoxide The printing method according to item 1, characterized by the above.

[0011] 3 . The printing method according to item 1, wherein the temperature of the post-treatment liquid is 20°C or lower The printing method according to item 1, characterized by the above.

[0012] 4 . The printing method according to item 1, wherein the dissolving power of the post-treatment liquid for the sublimation coloring material at 25°C is 5 mass ppm or less The printing method according to item 1, characterized by the above.

[0013] 5. The dyeing method is a sublimation transfer method The textile printing method according to Item 1, characterized in that:

Effects of the Invention

[0014] By means of the above-mentioned measures of the present invention, a textile printing method that achieves both color developability and washing fastness can be provided.

[0015] Although the expression mechanism or action mechanism of the effect of the present invention has not been clarified, it is inferred as follows.

[0016] In the textile printing method of the present invention, a solvent having an I / O value of 3.0 or less and an aromatic heterocyclic compound are applied to a fabric in a pretreatment step. Due to its high hydrophobicity, the solvent having an I / O value of 3.0 or less readily dissolves sublimation coloring materials. Therefore, by applying the solvent to the fabric in the pretreatment step, the sublimation coloring material easily penetrates into the fibers of the fabric in a monomolecular state, and the fixing property and color developability of the sublimation coloring material are improved.

[0017] For the aromatic heterocyclic compound, CH-π interaction acts between it and a fabric containing natural fibers or synthetic cellulose fibers, and π-π interaction acts between it and the sublimation coloring material. Therefore, by applying the aromatic heterocyclic compound to the fabric in the pretreatment step, the sublimation coloring material is easily fixed to the fabric via the aromatic heterocyclic compound.

[0018] In the textile printing method of the present invention, a post-treatment liquid containing water is further applied to the fabric in a post-treatment step. This water enhances the interaction between the sublimation coloring material with low water solubility and the aromatic heterocyclic compound. This makes it difficult for the sublimation coloring material to elute during washing, thereby achieving both color developability and washing fastness.

Mode for Carrying Out the Invention

[0019] The present invention relates to a textile printing method for dyeing a fabric, characterized in that the fabric contains natural fibers or synthetic cellulose fibers, and comprises the steps of: applying a pretreatment solution to the fabric containing a solvent and an aromatic heterocyclic compound, wherein the ratio of inorganic to organic values ​​(I / O value) is 3.0 or less; applying a sublimation colorant to the fabric; and applying a posttreatment solution containing water to the fabric, in this order. This feature is a technical feature common to or corresponding to the embodiments described below.

[0020] In an embodiment of the printing method of the present invention, it is preferable that the solvent contains dimethyl sulfoxide. Dimethyl sulfoxide readily dissolves sublimation colorants into a monomolecular state, and readily improves the fixation and color development of the sublimation colorants.

[0021] In embodiments of the printing method of the present invention, it is preferable that the aromatic heterocyclic compound has a structure represented by the general formula (1) above. Compounds having the structure represented by the general formula (1) above have a high ability to capture sublimation colorants and easily improve the fixation, color development, and wash fastness of the sublimation colorants.

[0022] In an embodiment of the printing method of the present invention, it is preferable that the temperature of the post-treatment solution is 20°C or lower. This promotes the interaction between the sublimation colorant and the aromatic heterocyclic compound, thereby improving wash fastness.

[0023] In an embodiment of the printing method of the present invention, it is preferable that the solubility of the post-treatment solution for the sublimation colorant at 25°C is 5 ppm by mass or less. This suppresses the dissolution of the sublimation colorant fixed to the fibers of the fabric into the post-treatment solution, thereby preventing a decrease in color development. Furthermore, even if the sublimation colorant that has dissolved into the post-treatment solution remains in the fabric after drying, it becomes more susceptible to dissolution during washing. Therefore, suppressing the dissolution of the sublimation colorant into the post-treatment solution also contributes to improving wash fastness.

[0024] In an embodiment of the printing method of the present invention, it is preferable that the dyeing method is a sublimation transfer method from the viewpoint of achieving the effects of the present invention.

[0025] The present invention, its components, and embodiments and models for carrying out the present invention will be described in detail below. In this application, "~" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0026] The present invention relates to a textile printing method for dyeing a fabric, characterized in that the fabric contains natural fibers or synthetic cellulose fibers, and comprises the steps of: applying a pretreatment solution to the fabric containing a solvent and an aromatic heterocyclic compound, wherein the ratio of inorganic to organic values ​​(I / O value) is 3.0 or less; applying a sublimation colorant to the fabric (hereinafter also referred to as the dyeing step); and applying a posttreatment solution containing water to the fabric (hereinafter also referred to as the posttreatment step), in this order.

[0027] <1.Fabric> The fabric according to the present invention is characterized by containing natural fibers or synthetic cellulose fibers. When fabrics containing fibers that swell easily with water, such as natural fibers or synthetic cellulose fibers, are used, the leaching of sublimation dyes from the fabric becomes more likely, resulting in poorer wash fastness. The present invention is a printing method that solves this problem.

[0028] Examples of natural fibers include natural cellulose fibers, hemp, wool, and silk. Examples of synthetic cellulose fibers include regenerated cellulose fibers such as rayon, and semi-synthetic cellulose fibers such as acetate.

[0029] The higher the content of natural fibers or synthetic cellulose fibers in the fabric, the more pronounced the effects of the present invention become. Specifically, the effects of the present invention become pronounced when the content of natural fibers or synthetic cellulose fibers is 30% by mass or more.

[0030] Other examples of fibers that may be included in woven fabrics include vinylon fibers, nylon fibers, acrylic fibers, polyurethane fibers, and polyester fibers.

[0031] The fabric may be made from these fibers in any form, such as woven, nonwoven, or knitted. Furthermore, the fabric may be a blended woven or nonwoven fabric of two or more types of fibers.

[0032] <2. Pre-treatment process> In the printing method of the present invention, the pretreatment step involves applying a pretreatment solution to the fabric.

[0033] <2-1. Components of the pretreatment solution> The pretreatment solution is characterized by containing a solvent with an inorganic-to-organic ratio (I / O value) of 3.0 or less and an aromatic heterocyclic compound.

[0034] Solvents with an I / O value of 3.0 or less readily dissolve sublimation dyes due to their high hydrophobicity. Therefore, by applying such solvents to the fabric in a pretreatment step, the sublimation dye can more easily penetrate the fabric fibers in a single-molecule state, improving color development.

[0035] The "I / O value" is the ratio of the inorganic value (I) to the organic value (O). The I / O value is also called the IOB (Inorganic Organic Balance) value and is one of the indicators that shows the degree of polarity of a compound or component.

[0036] Detailed explanations of I / O values ​​can be found in references such as: Organic Concept Diagram (by Yoshio Koda, Sankyo Publishing (1984)); KUMAMOTO PHARMACEUTICAL BULLETIN, No. 1, Sections 1-16 (1954); and The Field of Chemistry, Vol. 11, No. 10, Sections 719-725 (1957).

[0037] The "inorganic value (I)" is a numerical representation of the influence of various substituents or bonds on the boiling point of an organic compound, based on the hydroxyl group. Specifically, if the distance between the boiling point curves of a straight-chain alcohol and a straight-chain paraffin is taken around the number of carbon atoms (5), it is approximately 100°C, so the influence of one hydroxyl group is defined as 100. The inorganic value (I) is a numerical representation of the influence of various substituents or bonds on the boiling point, based on this value. For example, the inorganic value (I) of a carboxyl group (-COOH) is 150, and the inorganic value (I) of a double bond is 2. The inorganic value (I) of certain organic compounds refers to the sum of the inorganic values ​​(I) of the various substituents or bonds that the organic compound possesses.

[0038] The "organicness value (O)" is determined using the methylene group within a molecule as the unit, and is based on the influence of that methylene group on the boiling point of the carbon atom representing it. Specifically, the average boiling point elevation due to the addition of one carbon atom in straight-chain saturated hydrocarbon compounds with around 5 to 10 carbon atoms is 20°C, so the organicness value of one carbon atom is set at 20 based on this standard. The value that quantifies the influence of various substituents or bonds on the boiling point, based on this value, becomes the organicness value (O). For example, the organicness value (O) of a nitro group (-NO2) is 70. The organicness value (O) of certain organic compounds means the sum of the organicness values ​​(O) of the various substituents or bonds that the organic compound possesses.

[0039] Generally, a smaller I / O value indicates nonpolarity (higher hydrophobicity, higher organicity), while a larger value indicates polarity (higher hydrophilicity, higher inorganicity).

[0040] Solvents with an I / O value of 3.0 or less include 2-pyrrolidone (I / O value: 1.15), ethylene glycol monoethylene ether (I / O value: 1.5), dimethyl sulfoxide (I / O value: 1.75), butyric acid (I / O value: 1.875), polyethylene glycol (I / O value: 2.0), isobutyric acid (I / O value: 2.143), 2,3-butanediol (I / O value: 2.5), and trimethylolethane (I / O value: 3.0).

[0041] The lower limit of the I / O value of the solvent is not particularly limited, but it is preferably 1.0 or higher from the viewpoint of making it easier to swell the inside of the fibers contained in the fabric.

[0042] Among the solvents mentioned above, dimethyl sulfoxide is particularly preferred because it readily dissolves sublimation colorants into single molecules and improves their fixation and color development properties.

[0043] The solvent content is preferably in the range of 50 to 99% by mass of the total pretreatment solution, and more preferably in the range of 70 to 99% by mass.

[0044] Aromatic heterocyclic compounds exhibit CH-π interactions with fabrics and π-π interactions with sublimation dyes. Therefore, by applying aromatic heterocyclic compounds to the fabric in a pretreatment step, the sublimation dyes become more easily fixed to the fabric via the aromatic heterocyclic compounds. Furthermore, the interaction between aromatic heterocyclic compounds and sublimation dyes is strengthened by the action of water added in a posttreatment step, improving wash fastness.

[0045] In this invention, "aromatic heterocyclic compound" refers to an aromatic compound whose aromatic ring is composed of carbon and a heteroatom other than carbon. Compounds in which the aromatic ring is composed solely of carbon and the heteroatom constitutes a substituent that substitutes for the aromatic ring are not included in aromatic heterocyclic compounds.

[0046] The aromatic heterocyclic compound contained in the pretreatment solution is more preferably a compound having the structure represented by the following general formula (1) due to its high ability to capture sublimation colorants.

[0047] [ka]

[0048] (In the formula, A represents a pyrazole ring, Ar1 and Ar2 each represent an aromatic hydrocarbon ring or an aromatic heterocycle, and may have substituents. R1 represents a hydrogen atom, an alkyl group, an acyl group, a sulfonyl group, an alkyloxycarbonyl group, or an aryloxycarbonyl group, q represents an integer from 1 to 2, and m and n represent integers from 1 to 3.)

[0049] Examples of aromatic hydrocarbon rings or aromatic heterocycles represented by Ar1 and Ar2 include benzene rings, pyrrole rings, pyrazole rings, imidazole rings, 1,2,3-triazole rings, 1,2,4-triazole rings, tetrazole rings, furan rings, oxazole rings, isoxazole rings, oxadiazole rings, isoxadiazole rings, thiophene rings, thiazole rings, isothiazole rings, thiadiazole rings, isothiadiazole rings, and so on.

[0050] Examples of substituents on Ar1 and Ar2 include halogen atoms (fluorine, chlorine, bromine, iodine, etc.), alkyl groups (methyl, ethyl, n-propyl, isopropyl, tert-butyl, n-octyl, 2-ethylhexyl, etc.), cycloalkyl groups (cyclohexyl, cyclopentyl, 4-n-dodecylcyclohexyl, etc.), alkenyl groups (vinyl, allyl, etc.), cycloalkenyl groups (2-cyclopenten-1-yl, 2-cyclohexen-1-yl, etc.), and alkynyl groups (ethynyl, propargyl). (e.g., p-tolyl group), aromatic hydrocarbon ring groups (phenyl group, p-tolyl group, naphthyl group, etc.), aromatic heterocyclic groups (2-pyrrole group, 2-furyl group, 2-thienyl group, pyrrole group, imidazolyl group, oxazolyl group, thiazolyl group, benzimidazolyl group, benzoxazolyl group, 2-benzothiazolyl group, pyrazolinone group, pyridyl group, pyridinone group, 2-pyrimidinyl group, triazine group, pyrazole group, 1,2,3-triazole group, 1,2,4-triazole group, oxazole group, isoxazole group, 1,2,4-oxadiazole group, 1,3,4 -Oxadiazole group, thiazole group, isothiazole group, 1,2,4-thiodiazole group, 1,3,4-thiadiazole group, etc.), cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group (methoxy group, ethoxy group, isopropoxy group, tert-butoxy group, n-octyloxy group, 2-methoxyethoxy group, etc.), aryloxy group (phenoxy group, 2-methylphenoxy group, 4-tert-butylphenoxy group, 3-nitrophenoxy group, 2-tetradecanoylaminophenoxy group, etc.), acyloxy group (formyloxy group) , acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group, etc.), amino group (amino group, methylamino group, dimethylamino group, anilino group, N-methyl-anilinino group, diphenylamino group, etc.), acylamino group (formylamino group, acetylamino group, pivaloylamino group, lauroylamino group, benzoylamino group, etc.), alkyl and arylsulfonylamino groups (methylsulfonylamino group, butylsulfonylamino group, phenylsulfonylamino group, 2,3,Examples include 5-trichlorophenylsulfonylamino group, p-methylphenylsulfonylamino group, etc., mercapto group, alkylthio group (methylthio group, ethylthio group, n-hexadecylthio group, etc.), arylthio group (phenylthio group, p-chlorophenylthio group, m-methoxyphenylthio group, etc.), sulfamoyl group (N-ethylsulfamoyl group, N-(3-dodecyloxypropyl)sulfamoyl group, N,N-dimethylsulfamoyl group, N-acetylsulfamoyl group, N-benzoylsulfamoyl group, N-(N'-phenylcarbamoyl)sulfamoyl group, etc.), sulfo group, acyl group (acetyl group, pivaloylbenzoyl group, etc.), carbamoyl group (carbamoyl group, N-methylcarbamoyl group, N,N-dimethylcarbamoyl group, N,N-di-n-octylcarbamoyl group, N-(methylsulfonyl)carbamoyl group, etc.).

[0051] Examples of R1 include halogen atoms (fluorine, chlorine, bromine, iodine, etc.), alkyl groups (methyl, ethyl, n-propyl, isopropyl, tert-butyl, n-octyl, 2-ethylhexyl, etc.), acyl groups (acetyl, pivaloylbenzoyl, etc.), sulfonyl groups (e.g., methylsulfonyl, ethylsulfonyl, etc.), alkyloxycarbonyl groups (e.g., methoxycarbonyl), aryloxycarbonyl groups (e.g., phenoxycarbonyl, etc.).

[0052] q represents an integer between 1 and 2, and m and n represent integers between 1 and 3.

[0053] The following example compounds (1) to (11) are specific examples of aromatic heterocyclic compounds. Of these, example compounds (1) and (3) are compounds having a structure represented by general formula (1).

[0054] [ka]

[0055] [ka]

[0056] Aromatic heterocyclic compounds are preferable to have a low molecular weight, as this allows them to capture sublimation colorants within the fibers of the fabric. Specifically, a molecular weight in the range of 200 to 1000 is preferred.

[0057] From the viewpoint of the ability to capture sublimation colorants, aromatic heterocyclic compounds are preferably such that their Rf (Retention Factor) value, determined by paper chromatography under the following conditions, is 0.7 or less, more preferably 0.5 or less, even more preferably 0.3 or less, and particularly preferably 0.2 or less.

[0058] [Conditions for the paper chromatography method] Procedure 1: A 10% solution of an aromatic heterocyclic compound is impregnated into cellulose filter paper, then dried to prepare a support. Step 2: A 0.1% solution of tetrahydrofuran sublimation colorant is spotted onto the carrier, then dried to prepare a developing sample. Step 3: Develop the sample with acetonitrile at 25°C for 3 minutes. Step 4: Calculate the Rf value using the following formula. (Formula) Rf value = Expansion distance of sublimation colorant / Expansion distance of acetonitrile

[0059] In this paper chromatography method, a cellulose filter paper on which an aromatic heterocyclic compound has been fixed is used as a support to develop a sublimation colorant. This method allows the strength of the CH-π interaction assumed to occur between the cellulose fiber or a fabric containing cellulose-like fibers and the aromatic heterocyclic compound to be reflected in the measured Rf value. Furthermore, by using a sublimation colorant as the target of development, the strength of the π-π interaction assumed to occur between the sublimation colorant and the aromatic heterocyclic compound can also be reflected in the measured Rf value. In other words, the Rf value obtained by this paper chromatography method represents the overall strength of the CH-π interaction and the π-π interaction. In other words, the Rf value is an indicator of the colorant-capturing ability of the aromatic heterocyclic compound (its ability to fix the sublimation colorant to the fabric). A smaller Rf value indicates greater colorant-capturing ability.

[0060] The following describes the details of each step in the paper chromatography method.

[0061] (Step 1) A 10% solution of an aromatic heterocyclic compound is impregnated into cellulose filter paper of type 5C as specified in JIS P 3801:1995, and then dried to prepare a support. The solvent used in the 10% solution of the aromatic heterocyclic compound is not particularly limited as long as it can dissolve the aromatic heterocyclic compound, and solvents that can be contained in the pretreatment solution can be used. The shape of the cellulose filter paper is not particularly limited and can be, for example, in strips. The size of the cellulose filter paper is not particularly limited, but it must be large enough to allow for sufficient unfolding in step 3. Impregnation of the cellulose filter paper with the solution is performed by immersing the cellulose filter paper in the solution for 1 minute. Drying conditions are not particularly limited as long as the support can be sufficiently dried to the extent that its mass stabilizes under a 25°C, 50% RH environment.

[0062] (Step 2) A 0.1% solution of tetrahydrofuran, a sublimation colorant used for textile printing, is spotted onto the carrier and then dried to prepare a developing sample. The solution can be spotted using a capillary. The amount of solution spotted is preferably 0.5 to 2 μL, and more preferably 1 μL. The spot should be positioned 1 cm from the bottom edge of the cellulose filter paper. Drying conditions are not particularly limited, as long as the sample is sufficiently dried to the point where its mass stabilizes under a 25°C, 50% RH environment.

[0063] (Step 3) Develop the sample in acetonitrile for 3 minutes at 25°C. Specifically, place the sample upright in a developing tank containing acetonitrile, ensuring that the spotted portion in step 2 is not submerged in the acetonitrile. Cover the developing tank and begin the development process. The development time is 3 minutes from the moment the cellulose filter paper is immersed in the acetonitrile.

[0064] (Step 4) The Rf value is calculated using the following formula. (Formula) Rf value = Expansion distance of sublimation colorant / Expansion distance of acetonitrile

[0065] The "development distance of the sublimation pigment" is the distance from the center of the spotted area in step 2 to the darkest point of the spot after development. If it is difficult to determine the darkest point, the distance is the distance from the center of the spotted area in step 2 to the center of the leading and trailing ends of the spot.

[0066] The "acetonitrile deployment distance" is defined as the distance from the center of the spotted area in step 2 to the tip of the acetonitrile after deployment.

[0067] The Rf value may be the average of multiple measurements, taking into consideration the accuracy of the measurement.

[0068] From the viewpoint of the ability to capture the sublimation colorant, the content of aromatic heterocyclic compounds is preferably in the range of 1 to 30% by mass of the total pretreatment solution.

[0069] The pretreatment solution may contain other components as needed. Examples of other components include water, surfactants, preservatives, pH adjusters, etc.

[0070] Examples of water include deionized water, distilled water, and pure water. The water content is preferably in the range of 0 to 95% by mass of the total pretreatment solution, and more preferably in the range of 0 to 50% by mass.

[0071] While surfactants can be used without particular limitations, when the components of the printing ink contain anionic compounds, the ionic nature of the surfactant is preferably anionic, nonionic, or betaine. Specifically, fluorine-based or silicone-based surfactants with high static surface tension reduction ability, anionic surfactants such as dioctyl sulfosuccinate and sodium dodecyl sulfate with high dynamic surface tension reduction ability, and nonionic surfactants such as relatively low molecular weight polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, acetylene glycols, Pluronic-type surfactants (Pluronic is a registered trademark), and sorbitan derivatives are preferably used. It is also preferable to use a fluorine-based or silicone-based surfactant in combination with a surfactant with high dynamic surface tension reduction ability.

[0072] Examples of preservatives include aromatic halogen compounds (e.g., PreventolCMK), methylenedithiocyanates, halogenated nitrogen-sulfur compounds, and 1,2-benzisothiazolin-3-one (e.g., PROXELGXL).

[0073] Examples of pH adjusters include citric acid, sodium citrate, hydrochloric acid, and sodium hydroxide.

[0074] <2-2. Physical properties of the pretreatment solution> The viscosity of the pretreatment solution at 25°C can be appropriately adjusted depending on the method of application to the fabric. For example, when the pretreatment solution is applied by an inkjet method, the viscosity of the pretreatment solution is preferably in the range of 4 to 20 mPa·s. The viscosity of the pretreatment solution can be measured at 25°C using an E-type viscometer.

[0075] <2-3. Application of pretreatment solution to the fabric> In the pretreatment step, a pretreatment solution is applied to the fabric. The pretreatment solution may be applied to the entire surface of the fabric, or it may be applied selectively only to the areas to be dyed with the sublimation dye, depending on the image to be printed.

[0076] Any known method can be used without particular limitation for applying the pretreatment solution to the fabric. Specifically, spray methods, mangle methods (pad methods or dipping methods), coating methods, inkjet methods, etc., can be used. For example, if you want to apply the pretreatment solution only to a predetermined area, or if you want to continuously apply the pretreatment solution and printing ink using a direct sublimation method in the dyeing process described later, the inkjet method is preferable. From the viewpoint of applying a predetermined amount of pretreatment solution in a short time, the mangle method or coater method is preferable.

[0077] In the mangle method, the amount of pretreatment solution applied can be adjusted by immersing the fabric in the pretreatment solution stored in the bathtub and then wringing it out.

[0078] In the inkjet method, an inkjet recording device is used to eject droplets of pretreatment solution from the inkjet recording head toward the fabric. The amount of pretreatment solution applied can be adjusted by controlling the droplet volume of each solution and the dot density.

[0079] The temperature of the pretreatment solution is not particularly limited, but it can be, for example, 15-30°C.

[0080] The amount of pretreatment solution applied is not particularly limited and can be adjusted according to the content of aromatic heterocyclic compounds in the pretreatment solution, the amount of sublimation colorant applied in the dyeing process, and so on.

[0081] After applying the pretreatment solution to the fabric, a drying process may be performed, but it is preferable for some solvent to remain. When drying, heat drying using, for example, hot air, a hot plate, or a heat roller can be employed. The drying temperature can be, for example, in the range of 100 to 130°C.

[0082] <3. Dyeing process> In the printing method of the present invention, the dyeing step involves applying a dyeing ink containing a sublimation colorant to the fabric, thereby imparting the sublimation colorant to the fabric.

[0083] <3-1. Components of textile printing ink> The ink for textile printing contains at least a sublimation colorant and may also contain water, organic solvents, dispersants, etc.

[0084] In this invention, "sublimation colorant" refers to a colorant that has the property of sublimating when heated.

[0085] The sublimation colorant is preferably a dispersible dye that is insoluble or sparingly soluble in water. Here, insoluble or sparingly soluble in water means that the solubility in water at 25°C is 10 mg / L or less, preferably 5 mg / L or less, and more preferably 1 mg / L or less.

[0086] The chemical structure of the sublimation colorant is not particularly limited, but it is preferable that it has multiple aromatic rings. Having multiple aromatic rings allows for strong π-π interactions with the aromatic heterocyclic compound derived from the pretreatment solution, making it easier for the sublimation colorant to adhere to the fabric.

[0087] Examples of dispersible dyes among sublimation colorants include the following dyes:

[0088] C.I. Disperse Yellow 3, 4, 5, 7, 9, 13, 24, 30, 33, 34, 42, 44, 49, 50, 51, 54, 56, 58, 60, 63, 64, 66, 68, 71, 74, 76, 79, 82, 83, 85, 86, 88, 90, 91, 93, 98, 99, 100, 104, 114, 116, 118, 119, 122, 124, 126, 135, 140, 141, 149, 160, 162, 163, 164, 165, 179, 180, 182, 183, 186, 192, 198, 199, 202, 204, 210, 211, 215, 216, 218, 224, etc.,

[0089] C.I. Disperse Orange 1, 3, 5, 7, 11, 13, 17, 20, 21, 25, 29, 30, 31, 32, 33, 37, 38, 42, 43, 44, 45, 47, 48, 49, 50, 53, 54, 55, 56, 57, 58, 59, 61, 66, 71, 73, 76, 78, 80, 89, 90, 91, 93, 96, 97, 119, 127, 130, 139, 142, etc.,

[0090] C.I. Disperse Red 1, 4, 5, 7, 11, 12, 13, 15, 17, 27, 43, 44, 50, 52, 53, 54, 55, 56, 58, 59, 60, 65, 72, 73, 74, 75, 76, 78, 81, 82, 86, 88, 90, 91, 92, 93, 96, 103, 105, 106, 107, 108, 110, 111, 113, 117, 118, 121, 122, 126, 127, 128, 131, 132, 134, 135, 137, 143, 145, 146, 151, 152, 153, 154, 157, 159, 164, 167, 169, 177, 179, 181, 183, 184, 185, 188, 189, 190, 191, 192, 200, 201, 202, 203, 205, 206, 207, 210, 221, 224, 225, 227, 229, 239, 240, 257, 258, 277, 278, 279, 281, 288, 289, 298, 302, 303, 310, 311, 312, 320, 324, 328, etc.,

[0091] CIDisperse Violet 1, 4, 8, 23, 26, 27, 28, 31, 33, 35, 36, 38, 40, 43, 46, 48, 50, 51, 52, 56, 57, 59, 61, 63, 69, 77, etc.

[0092] CIDisperse Green 9 etc.

[0093] CIDisperse Brown 1, 2, 4, 9, 13, 19 etc.

[0094] CIDisperse Blue 3, 7, 9, 14, 16, 19, 20, 26, 27, 35, 43, 44, 54, 55, 56, 58, 60, 62, 64, 71, 72, 73, 75, 79, 81, 82, 83, 87, 91, 93, 94, 95, 96, 102, 106, 108, 112, 113, 115, 118, 120, 122, 125, 128, 130, 139, 141, 142, 143, 146, 148, 149, 15 3, 154, 158, 165, 167, 171, 173, 174, 176, 181, 183, 185, 186, 187, 189, 197, 198, 200, 201, 205, 207, 211, 2 14, 224, 225, 257, 259, 267, 268, 270, 284, 285, 287, 288, 291, 293, 295, 297, 301, 315, 330, 333, 359, 360, etc.

[0095] CIDisperse Black 1, 3, 10, 24 etc.

[0096] The molecular weight of the sublimation colorant is not particularly limited, but from the viewpoint of making the sublimation colorant easier to sublimate, a small molecular weight (e.g., 200-350) is preferable. On the other hand, from the viewpoint of making it difficult for the sublimation colorant that has penetrated the fabric to escape, a moderately large molecular weight (e.g., 350-500) is preferable.

[0097] The sublimation colorants contained in the printing ink may or may not be crystallized.

[0098] The average particle size of the sublimation pigment in the textile printing ink is not particularly limited, but from the viewpoint of injection stability when applied by an inkjet method, it is preferable to have a particle size of 300 nm or less. The average particle size can be determined using a commercially available particle size analyzer that employs methods such as light scattering, electrophoresis, or laser Doppler. For example, a Malvern Zetasizer 1000 can be used as a particle size analyzer.

[0099] The content of sublimation pigment in textile printing ink is not particularly limited, but it is preferably in the range of 2 to 10% by mass relative to the total amount of textile printing ink. If the sublimation pigment content is 2% by mass or more, it is easier to form high-density images, and if it is 10% by mass or less, the viscosity of the textile printing ink does not become too high, so the injection stability when applied by an inkjet method is not easily impaired. From the same viewpoint, it is more preferable that the sublimation pigment content is in the range of 5 to 10% by mass relative to the total amount of textile printing ink.

[0100] Examples of water that can be contained in textile printing inks include deionized water, distilled water, and pure water. The water content in textile printing inks is preferably in the range of 40 to 98% by mass, and more preferably in the range of 50 to 70% by mass, relative to the total amount of the textile printing ink.

[0101] Water-soluble organic solvents are preferred as organic solvents that can be contained in textile printing inks.

[0102] The content of the water-soluble organic solvent is preferably in the range of 20 to 70% by mass relative to the total amount of the textile printing ink. If the content of the water-soluble organic solvent is 20% by mass or more relative to the total amount of the textile printing ink, the dispersibility and injection properties of the sublimation colorant are more easily improved, and if it is 70% by mass or less, the drying properties of the textile printing ink are less likely to be impaired.

[0103] The total content of water and water-soluble organic solvent is preferably in the range of 90 to 98% by mass, and more preferably in the range of 90 to 95% by mass, relative to the total amount of the printing ink.

[0104] Examples of water-soluble organic solvents include alcohols (e.g., methanol, ethanol, propanol, pentanol, hexanol, cyclohexanol, benzyl alcohol), polyhydric alcohols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, glycerin, compounds represented by the general formula (2) below), and polyhydric alcohol ethers (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether) This includes ethers (e.g., diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether), amines (e.g., ethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine, triethylenetetramine), amides (e.g., formamide, N,N-dimethylformamide, N,N-dimethylacetamide), heterocyclic compounds (e.g., 2-pyrrolidone, N-methyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidine), sulfoxides (e.g., dimethyl sulfoxide), and sulfones (e.g., sulfolane).

[0105] [ka]

[0106] (In the formula, R 11 Both x, y, and z represent either an ethylene glycol group (-OCH2CH2-) or a propylene glycol group (-OCH(CH3)CH2-). x, y, and z are all positive integers, and x+y+z=3 to 30.

[0107] When the fabric contains hydrophilic fibers such as natural fibers or synthetic cellulose fibers, it is preferable that the printing ink does not thicken easily upon drying, from the viewpoint of promoting the penetration of the printing ink into the fabric and minimizing the impairment of injection stability in the inkjet method. Therefore, it is preferable that the printing ink contains a high-boiling-point solvent, such as a water-soluble organic solvent, with a boiling point of 200°C or higher.

[0108] Examples of high-boiling-point solvents with a boiling point of 200°C or higher include polyols and polyalkylene oxides. Examples of polyols with a boiling point of 200°C or higher include dihydric alcohols such as 1,3-butanediol (boiling point 208°C), 1,6-hexanediol (boiling point 223°C), and polypropylene glycol; and trihydric or higher alcohols such as glycerin (boiling point 290°C) and trimethylolpropane (boiling point 295°C). Examples of polyalkylene oxides with a boiling point of 200°C or higher include ethers of dihydric alcohols such as diethylene glycol monoethyl ether (boiling point 202°C), triethylene glycol monomethyl ether (boiling point 245°C), tetraethylene glycol monomethyl ether (boiling point 305°C), and tripropylene glycol monoethyl ether (boiling point 256°C), as well as ethers of trihydric or higher alcohols such as polypropylene glycol and glycerin (boiling point 290°C) and hexanetriol.

[0109] The dispersants that can be contained in the printing ink can be selected according to the type of sublimation colorant. Examples of dispersants include formalin condensates of sodium creosote oil sulfonate, formalin condensates of sodium cresol sulfonate and sodium 2-naphthol-6-sulfonate, formalin condensates of sodium cresol sulfonate, formalin condensates of sodium phenol sulfonate, formalin condensates of sodium β-naphthol sulfonate, formalin condensates containing sodium β-naphthalene sulfonate and sodium β-naphthol sulfonate, alkylene oxides containing ethylene oxide and propylene oxide, alkylable compounds containing fatty alcohols, fatty amines, fatty acids, phenols, alkylphenols and carboxylic acid amines, lignin sulfonates, sodium paraffin sulfonate, copolymers of α-olefins and maleic anhydride, and known comb-type block polymers.

[0110] Examples of comb-type block polymers include DISPERBYK-190, DISPERBYK-194N, DISPERBYK-2010, DISPERBYK-2015, and BYK-154 from BIC Chemie ("DISPERBYK" and "BYK" are registered trademarks of the company).

[0111] The dispersant content is not particularly limited, but it is preferably in the range of 20 to 200% by mass relative to the sublimation colorant. When the dispersant content is 20% by mass or more relative to the mass of the sublimation colorant, the dispersibility of the sublimation colorant tends to be higher. When the dispersant content is 200% by mass or less relative to the sublimation colorant, the decrease in injection properties due to the dispersant tends to be suppressed.

[0112] Printing inks may contain other components as needed. Examples of other components include surfactants, preservatives, and pH adjusters. These can be the same surfactants, preservatives, and pH adjusters that may be contained in the pretreatment solution.

[0113] <3-2. Physical properties of inks for textile printing> From the viewpoint of injectionability when applied by an inkjet method, the viscosity of the textile printing ink at 25°C is preferably in the range of 3 to 20 mPa·s, and more preferably in the range of 4 to 12 mPa·s. The viscosity of the ink can be measured at 25°C using an E-type viscometer.

[0114] <3-3. Application of printing ink to fabric (dyeing)> In the dyeing process, a sublimation dye is applied to the fabric after the pretreatment process.

[0115] It is preferable that the pretreatment solution applied to the fabric in the pretreatment step remains undried during the dyeing step. Specifically, it is preferable that 20% or more of the pretreatment solution remains relative to the mass of the fabric before the pretreatment step. This causes the inside of the fabric fibers to swell, improving the fixation and color development of the sublimation dye.

[0116] Examples of dyeing methods in the dyeing process include sublimation transfer and direct sublimation, and from the viewpoint of achieving the effects of the present invention, the sublimation transfer method is preferred.

[0117] (Sublimation transfer method) The sublimation transfer method is a dyeing method in which printing ink is applied to a transfer medium, and then the printing ink is transferred from the transfer medium to the fabric.

[0118] In dyeing using the sublimation transfer method, first, printing ink is applied to the transfer medium, and then dried to form an ink layer (transfer image) corresponding to the printed image. The method of applying the printing ink is not particularly limited, but it is preferable to use an inkjet method because it enables high-precision printing.

[0119] The transfer medium is not particularly limited, as long as it can form an ink layer on its surface and transfer that ink layer to a fabric. Paper with an ink-receiving layer formed on its surface using inorganic fine particles such as silica is preferred as the transfer medium. Examples of transfer media include inkjet-specific paper and transfer paper.

[0120] Next, the surface of the transfer image on the transfer medium is brought into contact with the surface of the fabric and heat-pressed. This causes the sublimation colorant in the transfer image formed on the transfer medium to sublimate and transfer to the fabric, thereby dyeing the fabric.

[0121] The pressing temperature depends on the sublimation temperature of the sublimation colorant, but is preferably in the range of 180 to 210°C. The pressing pressure is 200 to 500 g / cm² for flat molds. 2 Within the range of 2-6 kg / cm² for continuous applications. 2 It is preferable that the range be within this range. The pressing time depends on the pressing temperature and pressing pressure, but it is preferable that it be within the range of 30 to 180 seconds.

[0122] (Direct sublimation method) The direct sublimation method is a dyeing method in which printing ink is applied directly to the fabric.

[0123] In direct sublimation dyeing, the printing ink is applied directly to the fabric according to the printed image. The method of applying the printing ink is not particularly limited, but the inkjet method is preferred because it enables high-precision printing. Specifically, in the inkjet method, an inkjet recording device is used to eject droplets of printing ink from an inkjet recording head toward the fabric.

[0124] The surface temperature of the fabric when the ink droplets for printing land is not particularly limited, but from the viewpoint of suppressing the blurring of the image before color development, it is preferably in the range of 35 to 70°C.

[0125] The fabric is dyed by sublimating the sublimation colorant through heating the ink coating after impact. The heating method can be any conventionally known method and can be appropriately selected depending on the type of fabric, the components of the pretreatment solution, the components of the printing ink, etc. Examples of heating methods include steaming, baking with dry heat, thermosol, HT steamer with superheated steam, and hot press. Among these, steaming, baking, and hot press are preferred. The heating temperature is not particularly limited, but can be, for example, 95°C or higher and less than 220°C.

[0126] <4. Post-processing steps> In the printing method of the present invention, the post-treatment step involves applying a post-treatment solution to the fabric.

[0127] <4-1. Components of the post-treatment solution> The post-treatment solution is characterized by containing water. When the water-containing post-treatment solution is applied to the dyed fabric, the interaction between the sublimation dye, which has low water solubility, and the aromatic heterocyclic compound is strengthened. As a result, the sublimation dye is less likely to leach out during washing, improving wash fastness.

[0128] Examples of water contained in the post-treatment solution include ion-exchanged water, distilled water, and pure water. The water content in the post-treatment solution is not particularly limited, but is preferably in the range of 70 to 100% by mass, more preferably in the range of 90 to 100% by mass, and even more preferably in the range of 99.5 to 100% by mass.

[0129] The post-treatment solution may contain other components besides water, such as organic solvents, as long as they do not hinder the effects of the present invention.

[0130] <4-2. Dissolving power of post-treatment solution> The post-treatment solution preferably has low solubility for the sublimation colorant applied in the dyeing process. Specifically, the solubility of the post-treatment solution for the sublimation colorant at 25°C is preferably 5 ppm by mass or less, more preferably 3 ppm by mass or less, and even more preferably 1 ppm by mass or less.

[0131] The low dissolving power of the post-treatment solution for sublimation dyes prevents the sublimation dyes fixed to the fabric fibers from dissolving into the post-treatment solution. This prevents a decrease in color development. Furthermore, even if sublimation dyes that have dissolved into the post-treatment solution remain in the fabric after drying, they tend to dissolve more easily during washing. Therefore, suppressing the dissolution of sublimation dyes into the post-treatment solution also contributes to improved wash fastness.

[0132] The dissolving power of the post-treatment solution for sublimation colorants can be adjusted by changing the components of the post-treatment solution, taking into account the type of sublimation colorant. For example, surfactants tend to increase the dissolving power of sublimation colorants, so reducing the surfactant content in the post-treatment solution can lower its dissolving power. From this perspective, it is preferable that the post-treatment solution does not contain surfactants.

[0133] <4-3. Application of post-treatment solution to the fabric> In the post-treatment process, a post-treatment solution is applied to the fabric after the dyeing process.

[0134] The post-treatment process is preferably carried out within 12 hours after the dyeing process. This is to prevent the sublimation dye, which is in a molecular state in the fabric after the dyeing process, from undergoing excessive crystal growth due to moisture in the air before the post-treatment process. Uncontrolled crystal growth due to moisture in the air can cause a decrease in color development.

[0135] Any known method can be used without particular limitation for applying the post-treatment solution to the fabric. Specifically, spray methods, mangle methods (pad methods or dipping methods), coating methods, inkjet methods, etc., can be used. From the viewpoint of applying the post-treatment solution to a large amount of fabric at once, the mangle method is preferred. From the viewpoint of suppressing the elution of sublimation colorants into the post-treatment solution, the inkjet method is preferred.

[0136] The amount of post-treatment solution applied is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 100% by mass or more, relative to the mass of the fabric before the pre-treatment process.

[0137] The temperature of the post-treatment solution is preferably low from the viewpoint of promoting interaction between the sublimation colorant and the aromatic heterocyclic compound. Specifically, the temperature of the post-treatment solution is preferably 20°C or lower, more preferably 10°C or lower, and even more preferably 5°C or lower.

[0138] The method for drying the fabric after the post-processing step is not particularly limited. [Examples]

[0139] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. In the following examples, unless otherwise specified, the operations were carried out at room temperature (25°C). Unless otherwise specified, "%", "ppm", and "parts" mean "mass%", "mass ppm", and "mass parts", respectively.

[0140] [Preparation of pretreatment solution] Pretreatment solutions 1 to 5 were prepared by mixing each component according to the proportions listed in Table I.

[0141] [Table 1]

[0142] The structure of the compound used as an aromatic heterocyclic compound is shown below.

[0143] [ka]

[0144] The I / O values ​​for the organic solvents listed in Table I are the values ​​calculated using the method described above.

[0145] The Rf values ​​of the aromatic heterocyclic compounds listed in Table I were obtained by paper chromatography under the following conditions.

[0146] [Conditions for the paper chromatography method] Procedure 1: A support was prepared by impregnating a 10% solution of an aromatic heterocyclic compound into cellulose filter paper of type 5C as specified in JIS P 3801:1995, and then drying it. The solvent used for the 10% solution of the aromatic heterocyclic compound was the organic solvent contained in the pretreatment solution. The cellulose filter paper was cut into strips measuring 5 cm x 3 cm. Impregnation of the cellulose filter paper with the solution was performed by immersing the cellulose filter paper in the solution for 1 minute. After impregnation, drying was performed by removing excess material by sandwiching it between Kimwipes, and then drying it with a hot press at 180°C for 1 minute.

[0147] Procedure 2: A 0.1% tetrahydrofuran solution of CI Disperse Blue 359 was spotted onto the support material and then dried to prepare the developing sample. The solution was spotted using a capillary tube. The amount of solution spotted was 1 μL, and the diameter of the spot was approximately 2 mm. The spot was positioned 1 cm from the bottom edge of the cellulose filter paper. After spotting, the sample was thoroughly dried with warm air.

[0148] Step 3: The sample was developed in acetonitrile for 3 minutes at 25°C. Specifically, the sample was placed upright as much as possible in a developing tank filled with acetonitrile to a height of approximately 5 mm, so that the spotted portion in Step 2 was not submerged in the acetonitrile. Then, the developing tank was covered and the development was carried out. The development time was 3 minutes from the time the cellulose filter paper was immersed in the acetonitrile.

[0149] Step 4: The Rf value was calculated using the following formula. (Formula) Rf value = Expansion distance of the sublimation colorant / Expansion distance of acetonitrile

[0150] The "development distance of the sublimation colorant" was defined as the distance from the center of the spotted area in step 2 to the darkest point of the spot after development. If it was difficult to determine the darkest point, the distance was defined as the distance from the center of the spotted area in step 2 to the center of the leading and trailing ends of the spot.

[0151] The "acetonitrile deployment distance" was defined as the distance from the center of the spotted area in step 2 to the tip of the acetonitrile after deployment.

[0152] For each aromatic heterocyclic compound, the measurement was performed three times, and the average value was adopted as the Rf value.

[0153] [Preparation of ink for textile printing] Disperbyk-190 (manufactured by Bic Chemie Japan, acid value 10 mg KOH / g) and deionized water were mixed and stirred until homogeneous. Then, CI Disperse Blue 359 was added as a sublimation colorant (dispersible dye), pre-mixed, and dispersed until the Z-average particle size, measured by dynamic light scattering, was within the range of 150-200 nm, to prepare a dispersion with a sublimation colorant concentration of 20% by mass. At this time, the amounts of dispersant, deionized water, and sublimation colorant were adjusted so that the sublimation colorant content was 20% by mass of the total mass of the dispersion, and the amount of solids in the dispersant was 30% of the total mass of the sublimation colorant. The Z-average particle size was measured by dynamic light scattering using a Zetasizer 1000, manufactured by Malvern ("Zetasizer" is a registered trademark of the company), in a sand grinder filled with 0.5 mm zirconia beads at a volume percentage of 50%.

[0154] The obtained dispersion was mixed with 30% by mass of the following: 10% by mass of glycerin as an organic solvent, 25% by mass of ethylene glycol, appropriate amounts of Proxel GXL as a preservative, and sodium citrate hydrate as a pH adjuster. The mixture was then mixed with deionized water to a total of 100% by mass. The mixture was then filtered through a 1 μm mesh filter. This prepared a textile printing ink (blue sublimation ink) containing 6% by mass of CI Disperse Blue 359.

[0155] [Preparation of post-treatment solution] Each component was mixed according to the proportions listed in Table II to prepare post-treatment solutions 1 to 3.

[0156] [Table 2]

[0157] The dissolving power listed in Table II was determined by the following method. 50 mg of powdered sublimation colorant (CI Disperse Blue 359) was mixed with 50 g of post-treatment solution at 1.25°C. 2. The mixture was stirred for 30 minutes. 3. The mixture was filtered using a 0.8 μm membrane filter. 4. The absorbance of the sublimation colorant in the mixed solution at its absorbance peak (around 600 nm) was determined by spectrophotometric measurement. 5. The amount of absorbance obtained was applied to a calibration curve representing the relationship between absorbance and the amount of sublimation pigment dissolved in the post-treatment solution [mass ppm] (the concentration of sublimation pigment dissolved in the post-treatment solution [mass ppm] relative to the post-treatment solution), thereby determining the amount of sublimation pigment dissolved [mass ppm]. This amount of sublimation pigment dissolved [mass ppm] was defined as the dissolving power of the post-treatment solution for the sublimation pigment [mass ppm].

[0158] [Printing] (1) Pretreatment process For the fabrics used, cotton broadcloth 40 (100% cotton) was used as fabric 1, and viscose 100 (100% rayon) was used as fabric 2. The types of fabrics used in each printing method are shown in Table III.

[0159] Each of the pre-treatment solutions prepared above was applied to the fabric using a main scan of 540 dpi and a sub-scan of 720 dpi to form a solid image of the pre-treatment solution. The application area was 200 mm x 200 mm, and the application amount was 40 g / m². 2 The pretreatment solution was applied using an inkjet printer equipped with an inkjet head (Konica Minolta head KM1024iMAE).

[0160] (2) Dyeing process The prepared textile printing ink was applied to the transfer paper using a main scan of 540 dpi and a sub-scan of 720 dpi to form a 200 mm x 200 mm solid image (ink layer) on the transfer paper. A4 sublimation transfer paper with adhesive (manufactured by Systemgraphi) was used as the transfer paper. An inkjet printer with an inkjet head (Konica Minolta head KM1024iMAE) was used to apply the textile printing ink. The ejection frequency was set to 22.4 kHz. After that, the transfer paper with the textile printing ink applied was dried in a dryer at 70°C for 30 seconds.

[0161] A solid image of printing ink formed on transfer paper was brought into contact with a solid image of undried pre-treatment solution formed on fabric, and then heat-pressed. A transfer device (heat press) was used for the heat pressing. The heat pressing conditions were: press temperature: 180°C, press time: 3 minutes, press pressure: 300 g / cm². 2 This process involved sublimation transfer of the printing ink on the transfer paper to the fabric, thereby imparting sublimation colorants to the fabric and causing it to develop color.

[0162] (3) Post-processing steps Two hours after the dyeing process, a post-treatment solution was applied to the colored fabric. The application method used for each printing method was either the mangle method or the inkjet method, as shown in Table III. The temperature of the post-treatment solution during application is also shown in Table III.

[0163] In the mangle method, the fabric was impregnated in the post-treatment solution for 5 seconds, then squeezed with a mangle to achieve a pickup rate of 100% by mass, and the post-treatment solution was applied. The pickup rate is a value calculated using the following formula. Pickup rate [mass %] = Mass of post-treatment solution [g] / Mass of fabric before pre-treatment [g] × 100

[0164] In the inkjet method, the application rate is 60 g / m². 2 The post-treatment solution was applied in such a manner. At this time, the amount of post-treatment solution applied relative to the mass of the fabric before the pre-treatment process was 60% by mass.

[0165] Subsequently, the fabric was dried at 130°C.

[0166] [Evaluation of color developability] For the color density of the solid image formed on each fabric, the reflectance R of each fabric at 620 nm was measured using a spectrophotometer CM-25d (manufactured by Konica Minolta, Inc.) under the conditions of a D65 light source, a viewing angle of 2°, and status I λ and the K / S value was calculated.

[0167] The K / S value is an index of surface color density defined by the Kubelka-Munk formula below. A larger K / S value indicates higher color density and better color developability. K / S=(1-R λ ) 2 / 2R λ (Kubelka-Munk formula) K: light absorption coefficient S: light scattering coefficient R λ : surface reflectance

[0168] K / S values were calculated at 5 points within a 200 mm×200 mm solid image formed on each fabric. The 5 points in the solid image were a total of 5 points: the center point which is the intersection of the diagonal lines of the solid image, and the midpoints between each of the four corners and the center point, respectively.

[0169] The arithmetic mean of the K / S values was evaluated according to the following criteria, and a rank of 3 or higher was determined as a pass. The evaluation results are as shown in Table III. 5: The arithmetic mean of K / S values is 15 or higher 4: The arithmetic mean of K / S values is 10 or higher and less than 15 3: The arithmetic mean of K / S values is 7 or higher and less than 10 2: The arithmetic mean of K / S values is 4 or higher and less than 7 1: The arithmetic mean of K / S values is less than 4

[0170] [Evaluation of wash fastness] A wash fastness test was conducted in accordance with JIS L 0844 A-2. The staining of nylon fibers in composite test specimens (made by sewing together various fibers) was investigated. Specifically, a spectrophotometer CM-25d (manufactured by Konica Minolta) was used to measure the colorfastness of L before and after washing. * a * b * The values ​​were measured for each. Next, L * a * , b * ΔL is the difference before and after washing. * Δa * Δb * These values ​​were calculated separately. Next, the color change ΔE before and after washing was calculated using the following formula. A smaller value of ΔE indicates less discoloration and better wash fastness. ΔE=[(ΔL * ) 2 +(Δa * ) 2 +(Δb * ) 2 ] 1 / 2

[0171] ΔE was evaluated according to the following criteria, with a rank of 3 or higher being considered a pass. The evaluation results are shown in Table III. A rank of 3 or higher indicates a clear improvement effect. 5: ΔE is less than 15 4: ΔE is between 15 and 20 (inclusive). 3: ΔE is 20 or greater and less than 25 2: ΔE is between 25 and 30 (inclusive). 1: ΔE is 30 or greater

[0172] [Table 3]

[0173] The I / O values ​​listed in Table III represent the I / O values ​​of the organic solvent contained in the pretreatment solution. The Rf values ​​listed in Table III represent the Rf values ​​of the aromatic heterocyclic compounds contained in the pretreatment solution.

[0174] From the above results, it was confirmed that the printing method of the present invention can achieve both high color development and wash fastness.

Claims

1. A printing method for dyeing fabrics, The aforementioned fabric contains natural fibers or synthetic cellulose fibers, A step of applying a pretreatment solution containing a solvent and an aromatic heterocyclic compound, wherein the ratio of inorganic to organic values ​​(I / O value) is 3.0 or less, to the fabric, A step of applying a sublimation coloring agent to the fabric, The process includes, in this order, a step of applying a post-treatment solution containing water to the fabric, The aromatic heterocyclic compound has a structure represented by the following general formula (1). A printing method characterized by the following. 【Chemistry 1】 (In the formula, A represents a pyrazole ring. A ｒ１ and A ｒ２ Each represents an aromatic hydrocarbon ring or an aromatic heterocycle, and may have substituents. １ (where '' represents a hydrogen atom, alkyl group, acyl group, sulfonyl group, alkyloxycarbonyl group, or aryloxycarbonyl group. q represents an integer between 1 and 2. m and n represent integers between 1 and 2.)

2. The solvent comprises dimethyl sulfoxide. The printing method according to feature 1.

3. The temperature of the post-treatment liquid is 20°C or lower. The printing method according to feature 1.

4. The dissolving power of the post-treatment solution for the sublimation colorant at 25°C is 5 ppm by mass or less. The printing method according to feature 1.

5. The staining method is sublimation transfer. The printing method according to feature 1.

Images