JP2005089591A - Inkjet printing ink, inkjet recording method and inkjet printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inkjet printing ink excellent in jetting properties and preservation stability, an inkjet recording method and an inkjet printing method. <P>SOLUTION: The inkjet printing ink comprises at least a disperse dye, a dispersant, water, a water-soluble organic solvent and a polyvalent metal, where the dye solubility in the ink composition to which the polyvalent metal is not added is at least 1×10<SP>-5</SP>, the total content of the polyvalent metal is 1-1,000 ppm and the disperse dye has a structure capable of forming a chelate compound with the polyvalent metal. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an inkjet printing ink for inkjet printing, an inkjet recording method, and an inkjet printing method.

  In the field of textile printing, an inkjet textile printing method is desired for shortening the delivery time and dealing with small-quantity, multi-product production. Disperse dyes are generally used for dyeing fibers such as polyester, but when disperse dyes are used for inkjet printing, in addition to performance such as color tone and fastness, which are the criteria for selection of dyes for conventional printing, inkjets are used. Since the recording method is ejection from fine nozzles, there are restrictions such as dispersion suitability for making fine particles, prevention of nozzle clogging, and dispersion stability, and there are many restrictions on dye selection. In addition, the recording ink for ink jet textile printing has problems such as that fine discharge nozzles are not clogged with coarse particles and the like, and there is no change in ink physical properties and no precipitation of solids during production or storage. In particular, an ink having a disperse dye as a colorant is a dispersion system in which fine colorant particles are dispersed in an aqueous medium. Therefore, coarse particles contained in the ink are dispersed in addition to fine dust. There are large particles formed by agglomeration of the particles during the storage process, and coarse particles are likely to be formed as compared with a dye ink that is a complete solution. For this reason, a method of removing coarse particles in ink that causes clogging of nozzles and solid analysis by performing filtration or centrifugation during the manufacturing process is disclosed (for example, see Patent Documents 1 and 2). .)

Various proposals have been made to stably disperse the facial department in the ink composition. For example, the use of a polymer having a lipophilic part and a hydrophilic part as a dispersing agent for dispersing a facial department has been proposed (for example, see Patent Document 3). As a dispersant for dispersing a pigment, use of a polymer having a lipophilic part and a hydrophilic part having a molecular weight in a specific range has been proposed (for example, see Patent Document 4).
Japanese Unexamined Patent Publication No. 64-48875 JP-A-2-255875 Japanese Patent Publication No. 55-35434 Japanese Patent Publication No. 4-5703

  However, the method of removing coarse particles during production cannot cope with the coarse particles generated during storage. Moreover, in the disperse dye ink, even if the type of the dispersant is optimized, it cannot be completely solved.

  In view of such circumstances, it is an object of the present invention to provide an inkjet printing ink, an inkjet recording method, and an inkjet printing method that are excellent in emission and storage stability.

The object of the present invention is achieved by the following configurations.
(Claim 1)
In an inkjet printing ink containing at least a disperse dye, a dispersant, water, a water-soluble organic solvent, and a polyvalent metal, the dye solubility in an ink composition not containing the polyvalent metal is 1 × 10 ⁻⁵ or more, An ink-jet printing ink, wherein the total content of valent metals is 1 ppm to 1000 ppm, and the disperse dye has a structure capable of forming a chelate compound with a polyvalent metal.
(Claim 2)
In an inkjet printing ink containing at least a disperse dye, a dispersant, water, a water-soluble organic solvent, and a polyvalent metal, the dye solubility in an ink composition not containing the polyvalent metal is 1 × 10 ⁻⁴ or more, and the polyvalent An ink-jet printing ink characterized in that the total content of metals is 1 ppm to 1000 ppm and the disperse dye has a structure capable of forming a chelate compound with a polyvalent metal.
(Claim 3)
The ink-jet printing ink according to claim 1 or 2, wherein a total content of the polyvalent metal is 10 ppm to 1000 ppm.
(Claim 4)
The ink-jet printing ink according to claim 1 or 2, wherein a total content of the polyvalent metal is 100 ppm to 1000 ppm.
(Claim 5)
The said polyvalent metal is at least 1 sort (s) chosen from Ca, Mg, Ti, Al, Zn, Fe, Co, Ni, and Cu, The any one of Claims 1-4 characterized by the above-mentioned. Inkjet printing ink.
(Claim 6)
6. An ink jet recording method comprising using an ink jet head having a nozzle diameter of 30 [mu] m or less and the ink jet textile ink according to any one of claims 1 to 5.
(Claim 7)
The inkjet recording method according to claim 6, wherein the nozzle diameter is 20 μm or less.
(Claim 8)
An inkjet recording method comprising using an inkjet head having a driving frequency of 20 kHz or more and the inkjet textile printing ink according to any one of claims 1 to 5.
(Claim 9)
9. The ink jet recording method according to claim 8, wherein the driving frequency is 30 kHz or more.
(Claim 10)
An ink jet recording method comprising using an ink jet head having an ink discharge speed of 6 m / s or more and the ink jet textile ink according to any one of claims 1 to 5.
(Claim 11)
The ink jet recording method according to claim 10, wherein the ink discharge speed is 8 m / s or more.
(Claim 12)
6. An ink jet printing method, wherein recording is performed using the ink jet textile printing ink according to any one of claims 1 to 5 on a fabric containing polyester fibers.
(Claim 13)
An ink-jet printing method comprising recording on a cloth containing polyester fibers by the ink-jet recording method according to any one of claims 6 to 11.

  INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an inkjet printing ink, an inkjet recording method, and an inkjet printing method that are excellent in emission and storage stability.

  The best mode for carrying out the present invention will be described in detail below, but the present invention is not limited thereto.

  The present inventor has intensively studied the above problems, and in particular, in ink jet inks in which disperse dyes are dispersed in water as a colorant, paying attention to the characteristics of disperse dyes that have extremely low solubility, can significantly improve storage stability. It was.

  The performance required for the ink-jet ink in which the disperse dye is dispersed in the form of fine particles is such that the dispersion stability is good, particle sedimentation does not occur, and the nozzles and filters are not blocked.

  In disperse dye inks, it has been found that the solubility of dyes in water, water-soluble organic solvents, surfactants, and dispersants has a significant effect on the storage stability and emission stability of dispersed particles.

  Ink using disperse dyes, inks with low dye solubility may have poor wettability due to low affinity between solvent, dispersant and colorant particles, making it difficult to completely remove bubbles. I understood. When sufficient deaeration cannot be performed, emission failure due to cavitation occurs.

  On the other hand, if the solubility of the dye is designed to be high in order to improve the wettability, the disperse dye has a small amount of solubility, so that the small particle dissolves during storage and precipitates on the large particle, that is, the crystal grows to increase the particle size. It became clear that clogging and sedimentation gradually occurred. The crystal growth rate depends on the solubility of the dye. That is, when the solubility is high, the crystal growth rate is high, and when the solubility is low, the opposite is true.

  As a result of the study by the present inventors, it is effective to add a polyvalent metal to an ink using a disperse dye having a chelatable structure in order to slow the crystal growth rate in an ink having sufficient dye wettability. It is as soon as it has been found that it is suitable and the present invention has been achieved.

That is, according to the present invention, in an inkjet printing ink containing at least a disperse dye, a dispersant, water, a water-soluble organic solvent, and a polyvalent metal, the dye solubility in the ink composition not containing the polyvalent metal is 10 ⁻⁵ or more. The total content of the polyvalent metal is 1 ppm to 1000 ppm, and the disperse dye has a structure capable of forming a chelate compound with the polyvalent metal.

  Although the detailed mechanism is under analysis, it is considered that the growth of molecular crystals is suppressed by forming a coordinate bond with a dye on the particle surface by a trace amount of polyvalent metal. In addition, it is considered that precipitation of crystals is suppressed by forming a coordinate bond with a dye dissolved in a trace amount.

  Hereinafter, the present invention will be described in detail.

  The disperse dye in the present invention refers to a nonionic dye having no ionic water-soluble group such as sulfonic acid or carboxy group. Unlike pigments, disperse dyes that are dispersed in water with a dispersant and used for dyeing synthetic fibers are soluble in organic solvents such as acetone and dimethylformamide. In addition, when the synthetic fiber is colored, it diffuses in the form of molecules in the fiber.

  Disperse dyes contained in ink jet textile printing inks were first developed for acetate fibers, but today there is much demand for dyes for polyester fibers. The dye for polyester is selected to have higher hydrophobicity and heat resistance than dye for acetate. The base of the disperse dye is a monoazo type, aminoanthraquinone type, or diphenylamine type having a relatively small molecule.

  The disperse dye used in the present invention has a structure capable of forming a coordination bond with a polyvalent metal. Specifically, the disperse dye is represented by chemical formulas (1) to (13) in the dye molecule. It has the structure represented.

(In the formula, R represents hydrogen or an alkyl group.)
In the present invention, it is essential that the dye solubility in the ink is 1 × 10 ⁻⁵ or more in terms of the dye solubility in the ink composition to which no polyvalent metal is added. Preferably it is 1 × 10 ⁻⁴ or more.

  The solubility of the dye in the ink can be measured by the following method using HPLC. At this time, as described above, the measurement is performed without adding a polyvalent metal to the ink.

<HPLC measurement conditions>
(apparatus)
Degasser: GS Science, Degassing unit Model 546B
Pump: Intelligent Pump L-6200 manufactured by Hitachi, Ltd.
Column gas oven: made by Gaskuro Kogyo detector: made by Hitachi, Ltd. UV-vis Detector L-4200
Integrator: GPC Integrator D-2520 manufactured by Hitachi, Ltd.
Sampler: Intelligent Auto Sampler AS-4000 manufactured by Hitachi, Ltd.
(Measurement condition)
Column: Inert Sil ODS-2 (reverse phase silica) 4.6 mm ID × 205 mmL
Oven: 40 ° C
Flow rate: 0.8ml / min
inj volume: 20 μl
Composition of eluent: eluent A: eluent B = 30: 70 up to 20 minutes, and thereafter eluent A: eluent B = 0: 100
Eluent A: 0.1 M ammonium acetate buffer pH 5
Eluent B: Methanol Detection wavelength: 260nm
The solubility of the disperse dye can be measured by a predetermined operation using the measurement apparatus and measurement conditions.

Examples of disperse dyes preferred for the present invention include:
C. I. Disperse Yellow 4, 5, 8, 16, 60, 82
C. I. Disperse Orange 29
C. I. Disperse Red 15, 141, 210
C. I. Disperse Violet 1, 4, 6
C. I. Disperse Green 1
C. I. Disperse Blue 3, 7, 15, 20, 22, 23, 26, 34, 35, 79, 125, 165, 183
However, it is not limited to these dyes.

  In the case of color development by high-temperature processing in textile printing using a disperse dye, it is preferable to select a disperse dye having good sublimation fastness, because the dye does not cause sublimation on the white background of a machine or fabric.

  As content of a disperse dye, 0.1-20 mass% is preferable, and 0.2-13 mass% is more preferable.

  The disperse dye may be used as a commercial product, but it is preferable to carry out a purification treatment. As a purification method, a known recrystallization method, washing or the like can be used. The organic solvent used in the purification method and purification treatment is preferably selected as appropriate according to the type of dye.

  The polyvalent metal according to the present invention is preferably at least one selected from Ca, Mg, Ti, Al, Zn, Fe, Co, Ni, and Cu.

  The polyvalent metal according to the present invention is preferably added in the form of a polyvalent metal salt. The anion is not particularly defined, but for example, chloride, sulfide, hydroxide and the like are used. A salt with an organic substance may be used, or an oxide that decomposes and dissolves after addition may be used.

  Specific polyvalent metal compounds are shown below, but are not particularly limited to these salts.

  For example, calcium chloride, calcium acetate, calcium oxide, magnesium chloride, magnesium fluoride, magnesium acetate, magnesium bromide, magnesium formate, magnesium nitrate, magnesium sulfate, titanium chloride, titanium iodide, aluminum chloride, aluminum oxide, aluminum bromide , Aluminum iodide, aluminum sulfate, aluminum nitrate, zinc chloride, zinc bromide, iron chloride, cobalt chloride, nickel chloride, copper chloride and the like. Among them, preferred is a chloride of each polyvalent metal.

  Examples of the water-soluble organic solvent of the present invention include polyhydric alcohols (for example, ethylene glycol, glycerin, 2-ethyl-2- (hydroxymethyl) -1,3-propanediol, tetraethylene glycol, triethylene glycol, Tripropylene glycol, 1,2,4-butanetriol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, 1,6-hexanediol, 1,2-hexanediol, 1,5-pentanediol, 1,2- Pentanediol, 2,2-dimethyl-1,3-propanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 3-methyl-1,3-butanediol, 2 -Methyl-1,3-propanediol, etc.), amines For example, ethanolamine, 2- (dimethylamino) ethanol, etc.), monohydric alcohols (eg, methanol, ethanol, butanol, etc.), polyhydric alcohol alkyl ethers (eg, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, triethylene glycol) Monomethyl ether, triethylene glycol monobutyl ether, ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, etc.), 2,2′-thiodiethanol, amides (eg N N-dimethylformamide), heterocycles (2-pyrrolidone, etc.), acetonitrile, etc. It is below.

  The amount of the water-soluble organic solvent is preferably 10 to 60% by mass with respect to the total ink mass.

  In the case of a water-insoluble dye, the ink used in the present invention can be dispersed by mixing a dye, a dispersing agent, a wetting agent, a medium, and optional additives and using a dispersing machine. As the disperser, a conventionally known ball mill, sand mill, line mill, high-pressure homogenizer, or the like can be used.

  The particle size of the disperse dye is preferably 300 nm or less as the average particle size and 900 nm or less as the maximum particle size. This is because when the average particle size and the maximum particle size are large, clogging is likely to occur in an ink jet printing method in which light is emitted from a fine nozzle, and stable emission is not possible. The average particle diameter can be obtained by a commercially available particle size measuring instrument using a light scattering method, an electrophoresis method, a laser Doppler method or the like. Specific examples of the particle diameter measuring apparatus include Zetar Sizer 1000 manufactured by Malvern.

  Dispersants preferably used in the present invention include, for example, formalin condensate of sodium creosote oil sulfonate (eg, Demol C), formalin condensate of sodium cresol sulfonate and sodium 2-naphthol-6-sulfonate, cresol sulfonic acid Formalin condensate of sodium, formalin condensate of sodium phenolsulfonate, formalin condensate of sodium β-naphtholsulfonate, formalin condensate of sodium β-naphthalenesulfonate (eg, demole N) and sodium naphtholsulfonate, lignin Examples thereof include sulfonates (for example, Vanillex RN), sodium paraffin sulfonate (for example, Efcol 214), copolymers of α-olefin and maleic anhydride (for example, Florene G-700), and the like.

  As for the usage-amount of a dispersing agent, 20-200 mass% is preferable with respect to a disperse dye. When the amount of the dispersant is small, the formation of fine particles and the dispersion stability is poor, and when the amount of the dispersant is large, the formation of fine particles and the dispersion stability is deteriorated and the viscosity becomes high. These dispersants may be used alone or in combination.

  Preferred wetting agents for the dispersion of the present invention are sodium dodecylbenzenesulfonate, sodium 2-ethylhexylsulfosuccinate, sodium alkylnaphthalenesulfonate, ethylene oxide adduct of phenol, ethylene oxide adduct of acetylenediol, and the like. Depending on the structure of the disperse dye used, foaming, gelation, and fluidity may be deteriorated during dispersion. Dispersants and wetting agents may be used in addition to wetting ability, atomization ability and dispersion stability. It is necessary to select in consideration of foaming during dispersion, gelation of the dispersion, fluidity of the dispersion, and the like. Dispersants and wetting agents affect the dyeability, dyeing rate, leveling, transferability, color tone, fastness, etc. of the fabric, and when developing at high temperatures, It is preferable to select in consideration of non-uniform dyeing due to tarring of the agent. Since there is no dispersant that satisfies all of the above requirements, it is necessary to select an optimal dispersant according to the dye to be dispersed and add an antifoaming agent or the like as necessary.

The ink of the present invention may contain a surfactant in order to adjust its surface tension, and any of cationic, anionic, amphoteric and nonionic can be used as the surfactant. . Examples of the cationic surfactant include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts, and the like. Examples of anionic surfactants include fatty acid soap, N-acyl-N-methylglycine salt, N-acyl-N-methyl-β-alanine salt, N-acyl glutamate, alkyl ether carboxylate, acylated peptide , Alkyl sulfonate, alkyl benzene sulfonate, alkyl naphthalene sulfonate, dialkyl sulfosuccinate, alkyl sulfoacetate, α-olefin sulfonate, N-acylmethyl taurine, sulfated oil, higher alcohol sulfate Salts, secondary higher alcohol sulfates, alkyl ether sulfates, secondary higher alcohol ethoxy sulfates, polyoxyethylene alkylphenyl ether sulfates, monoglyculates, fatty acid alkylolamide sulfates, alkyl ether phosphates Salt, alkyl phosphate ester salt and the like. Examples of amphoteric surfactants include carboxybetaine type, sulfobetaine type, aminocarboxylate, imidazolinium betaine and the like. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene secondary alcohol ether, polyoxyethylene alkylphenyl ether (eg, Emulgen 911), polyoxyethylene sterol ether, polyoxyethylene lanolin derivative, polyoxyethylene Polyoxypropylene alkyl ether (for example, Newpol PE-62), polyoxyethylene glycerin fatty acid ester, polyoxyethylene castor oil, hydrogenated castor oil, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyethylene glycol fatty acid ester, Fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, ® sugar fatty acid esters, fatty acid alkanolamides, polyoxyethylene fatty acid amides, polyoxyethylene alkyl amines, alkyl amine oxides, acetylene glycol, acetylene alcohol, and the like. The present invention is not limited to these.
When these surfactants are used, they can be used singly or as a mixture of two or more kinds. By adding 0.001 to 1.0% by mass with respect to the total amount of the ink, the surface of the ink can be used. The tension can be arbitrarily adjusted, which is preferable.

  In order to maintain the long-term storage stability of the ink, an antiseptic and an antifungal agent may be added to the ink. Examples of the antiseptic / antifungal agent include aromatic halogen compounds (for example, Preventol CMK), methylene dithiocyanate, halogen-containing nitrogen sulfur compounds, and 1,2-benzisothiazolin-3-one (for example, PROXEL GXL). The present invention is not limited to these.

  The material constituting the fabric used in the printing method of the present invention is not particularly limited as long as it contains fibers that can be dyed with disperse dyes. Among them, fibers such as polyester, acetate, and triacetate are contained. Those are preferred. Among them, a fabric containing at least polyester fibers is particularly preferable. As the fabric, the above-described fibers may be any form such as a woven fabric, a knitted fabric, and a non-woven fabric. Further, as the fabric that can be used in the present invention, it is preferable that the fiber that can be dyed with disperse dyes is 100%, but a mixed woven fabric with rayon, cotton, polyurethane, acrylic, nylon, wool, silk, etc. Alternatively, a blended nonwoven fabric or the like can also be used as a textile for printing. Moreover, as a thickness of the thread | yarn which comprises the above fabrics, the range of 10-100d is preferable.

  In the case of the inkjet printing method of the present invention, in order to obtain a uniform dyed product, natural impurities (oils, waxes, pectic substances, natural pigments, etc.) adhering to the fabric fiber before the water-soluble polymers are pretreated on the fabric ), It is desirable to wash away the residues (such as glue) and dirt of the chemical used in the fabric manufacturing process. As cleaning agents used for cleaning, alkalis such as sodium hydroxide and sodium carbonate, surfactants such as anionic surfactants and nonionic surfactants, enzymes and the like are used.

  In the textile printing method of the present invention, it is preferable to apply a pretreatment agent by a pad method, a coating method, a spray method or the like (pretreatment step) in order to prevent bleeding. Thereafter, an image is formed on the fabric containing fibers that can be dyed with a disperse dye by the ink jet recording method using the ink having the above-described configuration (ink application step), and then the ink is applied. The fabric is heat-treated (coloring step), and the heat-treated fabric is washed (washing step) to complete printing on the fabric and obtain a printed product.

  The pretreatment is not particularly limited as long as a method suitable for the fiber material and ink is appropriately selected from known methods such as pretreatment of water-soluble polymers on the fabric. For example, it is used for a fabric provided with 0.2 to 50% by mass of at least one substance selected from the group consisting of water-soluble metal salts, polycation compounds, water-soluble polymers, surfactants and water repellents. Therefore, it is possible to prevent bleeding at a high level and print a high-definition image on a fabric.

  The example of the specific water-soluble polymer used for pre-processing is given. Examples of natural water-soluble polymers include starches such as corn and wheat, cellulose derivatives such as carboxymethylcellulose, methylcellulose, and hydroxyethylcellulose, polysaccharides such as sodium alginate, guar gum, tamarind gum, locust bean gum, gum arabic, gelatin, Examples of protein substances such as casein and keratin, and synthetic water-soluble polymers include polyvinyl alcohol, polyvinyl pyrrolidone, and acrylic acid polymers. As the surfactant, for example, anionic, cationic, amphoteric, and nonionic surfactants are used. Typically, anionic surfactants include higher alcohol sulfates and sulfonates of naphthalene derivatives. Quaternary ammonium salt and the like as ionic surfactant; imidazoline derivative and the like as amphoteric surfactant; polyoxyethylene alkyl ether and polyoxyethylene propylene block polymer as nonionic surfactant Sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, ethylene oxide adduct of acetylene alcohol, and the like. Examples of the water repellent include silicon, fluorine-based and wax-based ones. These water-soluble polymers and surfactants previously applied to the fabric are stable against high-temperature environments because they do not cause stains due to tarring when ink-jet printing and color development at high temperatures. Preferably there is. Further, these water-soluble polymers and surfactants that are previously imparted to the fabric are preferably those that can be easily removed from the fabric by washing after ink jet printing and color development at high temperature.

  In the ink jet textile printing method for printing on a cloth, it is desirable to wind up the printed cloth after emitting the ink, develop a color by heating, and wash and dry the cloth. In ink jet textile printing, ink is not printed well just by printing it on a cloth and leaving it alone. In addition, when printing on a long fabric for a long time, the fabric comes out endlessly, and the printed fabric overlaps the floor etc., leaving a place that is unsafe and unexpectedly dirty. There is a case. Therefore, it is necessary to perform a winding operation after printing. During this operation, a medium not related to printing, such as paper, cloth, or vinyl, may be sandwiched between the cloths. However, it is not always necessary to wind up when cutting in the middle or short fabric.

  The color development step is a step of developing the original hue of ink by adhering to and fixing the dye in the ink that has only adhered to the fabric surface after printing and is not sufficiently adsorbed and fixed to the fabric. As the method, steaming by steam, baking by dry heat, thermosol, HT steamer by superheated steam, HP steamer by pressurized steam, etc. are used. They are appropriately selected depending on the material to be printed, ink, and the like. Further, the printed fabric may be immediately heat-treated or may be heat-treated after a while and may be dried and colored according to the intended use, and any method may be used in the present invention.

  When dyeing with a disperse dye, a carrier may be used in addition to a method of coloring at a high temperature. The compound used as the carrier is preferably a compound having characteristics such as large dyeing acceleration, simple use, stable, low burden on human body and environment, easy removal from the fiber, and no influence on dye fastness. Examples of the carrier include phenols such as o-phenylphenol, p-phenylphenol, methylnaphthalene, alkyl benzoate, alkyl salicylate, chlorobenzene and diphenyl, ethers, organic acids, hydrocarbons and the like. These promote the swelling and plasticization of difficult-to-dye fibers that are difficult to dye at temperatures around 100 ° C. like polyester, and make it easier for disperse dyes to enter the fibers. The carrier may be preliminarily adsorbed on the fibers of the fabric used for inkjet printing, or may be included in the inkjet ink.

  A cleaning step is necessary after the heat treatment. This is because a dye that has not participated in the dyeing remains, resulting in poor color stability and low fastness. It is also necessary to remove the pretreatment product applied to the fabric. If left as it is, not only the fastness is lowered, but also the fabric is discolored. Therefore, cleaning according to the object to be removed and the purpose is essential. The method is selected according to the material and ink to be printed. For example, in the case of polyester, treatment is generally performed with a mixed solution of caustic soda, a surfactant, and hydrosulfite. The method is usually carried out in a continuous type such as an open soaper or in a batch type using a liquid dyeing machine, and any method may be used in the present invention.

  Drying is required after washing. After the washed fabric is squeezed or dehydrated, it is dried or dried using a dryer, heat roll, iron or the like.

  It is preferable that a dyeing assistant is included in the inkjet ink for printing used for dyeing by the high-temperature steaming method or the fabric used for printing. The dyeing aid has the effect of making eutectic mixture with the water condensed in the form of cloth when steaming the printed fabric, reducing the amount of water that re-evaporates, and shortening the heating time. Further, this eutectic mixture has the effect of dissolving the dye on the fiber and promoting the diffusion rate of the dye into the fiber. Urea is mentioned as a dyeing assistant.

  In inks used in printers and the like, dissolved gas contained in the ink causes the resolution and clarity of the printed matter to be impaired and causes fine bubbles to be generated. Methods for degassing dissolved gas from the ink are roughly divided into a method of degassing by a physical method such as boiling or decompression, and a chemical method of mixing an absorbent into the ink. In the present invention, degassing can be performed by any means. In particular, the method of permeating and removing dissolved gas in the ink by passing the ink through the gas-permeable hollow fiber membrane and reducing the pressure on the outer surface side of the hollow fiber membrane has an adverse effect on the physical properties of the ink. This is preferable because the dissolved gas in the ink can be efficiently removed without giving. The dissolved air concentration can be determined based on the ratio of oxygen in the air by measuring the dissolved oxygen concentration. The dissolved oxygen concentration can be measured by the Ostwald method (Experimental Chemistry Course 1 Basic Operation [I], page 241, 1975, Maruzen), the mass spectrum method, or the galvanic cell type or polarographic type. It can be measured with a simple oxygen concentration meter or colorimetric analysis.

  In the present invention, in order to obtain a high-definition image, recording is preferably performed using an inkjet head having a nozzle diameter of 30 μm or less. In order to improve the granularity, the smaller one is preferable, but since the droplet volume becomes too small and is influenced by the air flow, the range of 10 μm to 20 μm is particularly preferable.

  The drive frequency of the ink jet head drive device is preferably 20 kHz or higher, and more preferably 30 kHz or higher in order to prevent ink clogging.

  For the same reason, the ink discharge speed is preferably 6 m / s or more, and more preferably 8 m / s or more.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

Example 1
<Preparation of ink>
(Dispersion-1)
The following mixture was dispersed using a sand grinder. Dispersion stopped when the average particle size reached 200 nm.

C. I. Disperse Yellow 149 25 parts Glycerin 20 parts Ion-exchanged water 25 parts Sodium lignin sulfonate 25 parts (Vanilex RN Nippon Paper Industries Co., Ltd.)
(Ink-1)
Further, the following components were mixed, filtered through a 3 μm membrane filter, and degassed to obtain ink-1.

Dispersion liquid-1 50 parts Ethylene glycol 48 parts Proxel GXL (S) 0.01 part (manufactured by Avicia Co., Ltd.)
Calcium chloride (added as calcium content) 100ppm
Ion exchange water remainder (dispersion-2)
The following mixture was dispersed using a sand grinder. Dispersion stopped when the average particle size reached 200 nm.

C. I. Disperse Blue 60 25 parts Glycerin 20 parts Ion-exchanged water 25 parts Sodium lignin sulfonate 25 parts (Vanilex RN Nippon Paper Industries Co., Ltd.)
(Ink-2)
Further, the following components were mixed, filtered through a 3 μm membrane filter, and degassed to obtain ink-2.

Dispersion liquid-2 50 parts Ethylene glycol 48 parts Florene G-700 (manufactured by Kyoeisha Chemical Co., Ltd.) 2.5 parts Proxel GXL (S) 0.01 part (manufactured by Avicia Co., Ltd.)
Calcium chloride (added as calcium content) 10000ppm
Ion-exchanged water balance In addition, Florene G-700 was neutralized in advance using a required amount of sodium hydroxide.

  In the same manner, inks 3 to 8 having the compositions shown in Table 1 were prepared.

  The prepared ink is passed through a gas permeable hollow fiber membrane (Mitsubishi Rayon), and the outer surface side of the hollow fiber membrane is decompressed with a water aspirator, so that the dissolved gas in the ink is removed. Removed.

  Further, the dye solubility in each ink formulation was measured by the measurement method described above.

  The following evaluation was performed for each of the produced inks.

<Evaluation>
(Crystal growth test)
The prepared ink is stored at 40 ° C. for 1 week and 2 weeks, respectively, and the shape of the particles is observed at 20,000 times using an electron microscope. When rod-shaped particles of 500 nm or more were observed, it was judged that there was a crystal growth product.

○: No crystal growth ×: Crystal growth (Thickening test)
Similarly, after storing at 40 ° C. for 2 weeks, the ink viscosity is measured with a viscometer. When the viscosity increased by 0.5 mPa · s or more as compared with the viscosity immediately after ink preparation, it was determined that there was a thickening.

○: No thickening ×: Thickening (Outgoing light evaluation 1)
Using a piezo-type head having a nozzle diameter of 30 μm, a driving frequency of 20 kHz, and the number of nozzles of 64, the emission was performed and the emission performance was evaluated. The drive voltage was adjusted so that the discharge speed was 6 m / s.

  In the environment of 25 ° C. and 50% relative humidity, 500 ml of each ink is continuously ejected, and bending and non-occurrence that occur until the ink runs out are evaluated according to the following evaluation criteria.

○: All nozzles are emitted. Δ: Curved by 1-3 nozzles and missing.

  X: Bending with 4 or more nozzles, and absence of fire.

(Outgoing light evaluation 2)
Evaluation was performed in the same manner as in the evaluation of emissivity 1 except that a piezo-type head having a nozzle diameter of 20 μm, a driving frequency of 30 kHz, and the number of nozzles of 64 was used and the driving voltage was adjusted so that the droplet velocity was 8 m / s.

○: All nozzles are emitted. Δ: Curved by 1-3 nozzles and missing.

  X: Bending with 4 or more nozzles, and absence of fire.

  Table 2 shows the results of the crystal growth test, the thickening test, and the emission test.

  The ink of the present invention was found to be superior in characteristics as compared with the ink of the comparative example.

Example 2
An ink was prepared in the same manner using a polyvalent metal compound shown in Table 3 below instead of the calcium chloride of ink 2 in Example 1.

  The same evaluation as in Example 1 was performed using the ink prepared above, and the results are shown in Table 4 below.

  The ink of the present invention reproduced Example 1 and was found to be superior in properties compared to the comparative example of Example 1.

Example 3
Using the ink produced in Example 1, on a fabric containing polyester fibers, a piezo-type head having a nozzle diameter of 20 μm, a driving frequency of 30 kHz, and a nozzle number of 64 is used, and the driving voltage is set so that the droplet velocity is 8 m / s. When ink jet printing was carried out after adjusting the above, the ink using the ink jet printing ink of the present invention had high print image density and excellent bleeding resistance. Furthermore, there was no problem with the light emission during long-term inkjet printing.

Claims (13)

In an inkjet printing ink containing at least a disperse dye, a dispersant, water, a water-soluble organic solvent, and a polyvalent metal, the dye solubility in an ink composition not containing the polyvalent metal is 1 × 10 ⁻⁵ or more, An ink-jet printing ink, wherein the total content of valent metals is 1 ppm to 1000 ppm, and the disperse dye has a structure capable of forming a chelate compound with a polyvalent metal. In an inkjet printing ink containing at least a disperse dye, a dispersant, water, a water-soluble organic solvent, and a polyvalent metal, the dye solubility in an ink composition not containing the polyvalent metal is 1 × 10 ⁻⁴ or more, and the polyvalent An ink-jet printing ink characterized in that the total content of metals is 1 ppm to 1000 ppm and the disperse dye has a structure capable of forming a chelate compound with a polyvalent metal. The ink-jet printing ink according to claim 1 or 2, wherein a total content of the polyvalent metal is 10 ppm to 1000 ppm. The ink-jet printing ink according to claim 1 or 2, wherein a total content of the polyvalent metal is 100 ppm to 1000 ppm. The said polyvalent metal is at least 1 sort (s) chosen from Ca, Mg, Ti, Al, Zn, Fe, Co, Ni, and Cu, The any one of Claims 1-4 characterized by the above-mentioned. Inkjet printing ink. 6. An ink jet recording method comprising using an ink jet head having a nozzle diameter of 30 [mu] m or less and the ink jet textile ink according to any one of claims 1 to 5. The inkjet recording method according to claim 6, wherein the nozzle diameter is 20 μm or less. An inkjet recording method comprising using an inkjet head having a driving frequency of 20 kHz or more and the inkjet textile printing ink according to any one of claims 1 to 5. 9. The ink jet recording method according to claim 8, wherein the driving frequency is 30 kHz or more. An ink jet recording method comprising using an ink jet head having an ink discharge speed of 6 m / s or more and the ink jet textile ink according to any one of claims 1 to 5. The ink jet recording method according to claim 10, wherein the ink discharge speed is 8 m / s or more. 6. An ink jet printing method, wherein recording is performed using the ink jet textile printing ink according to any one of claims 1 to 5 on a fabric containing polyester fibers. An ink-jet printing method comprising recording on a cloth containing polyester fibers by the ink-jet recording method according to any one of claims 6 to 11.