JP2010031402A - Ink jet printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink jet printing method by which an ink jet printed print controlling the blurring of the ink, preventing the overflow of the ink, and having an excellent back side image-drawing property can be obtained. <P>SOLUTION: Provided is the ink jet printing method comprising: heating a fabric comprising polyester yarns having an average thickness of 20 to 100d at 40 to 90°C; and then printing the fabric for the ink jet printing with an aqueous pigment ink for the ink jet in conditions comprising a record resolution of 360 to 1,440 dpi, an ink liquid drop amount of 3.5 to 56 pl and a maximum ink application amount of ≤40 ml/m<SP>2</SP>. Therein, the aqueous pigment ink comprises a pigment, water, a surfactant, a fixing resin and a water-soluble solvent, wherein the fixing resin is a water-soluble copolymer prepared by neutralizing and dissolving a copolymer containing a carboxyl group-having unsaturated vinyl monomer as a copolymerization component with an amine; and the water-soluble solvent is a glycol ether compound or a 1,2-alkanediol compound. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an inkjet textile printing method, and more particularly to an inkjet textile printing method in which an inkjet textile fabric mainly composed of polyester fibers is heated and recorded using an aqueous pigment ink.

  The image recording method by the ink jet method is a method in which minute droplets of ink are ejected and adhered to a recording medium, and the mechanism is relatively simple and inexpensive, and has the advantage that a high-definition and high-quality image can be formed. is there.

  So-called inkjet printing, in which recording is performed on a fabric by taking advantage of the inkjet method, is also performed. Ink-jet printing, unlike conventional printing methods, does not require the production of a plate and is suitable for producing a small amount of various images. In addition, since only an amount of ink necessary for image formation is used, the image forming method has little waste liquid and is excellent in environmental suitability.

  The ink-jet textile fabric is required to have performances such as ink coloring property, fixing property, drying property, and suppression of ink bleeding. Conventionally, in order to satisfy these required performances, the fabric has been preliminarily treated in advance. However, through the complicated pretreatment process, the advantage of the simplicity of the ink jet system cannot be fully utilized. In addition, the superiority or inferiority of the printed image after the final process is often due to the basic characteristics of the fabric used and the basic characteristics of the ink.

  Patent Document 1 describes a method in which a reaction liquid containing a reactive agent is attached to a cloth in advance and then a pigment ink is ejected. However, a process of attaching the reaction liquid is necessary and complicated.

Patent Document 2 describes a method of using a colorant including a pigment with a polymer having a crosslinked structure for ink jet printing, but even with this technique, the problem of bleeding cannot be solved.
JP 2003-55886 A JP 2002-338859 A

  The present invention has been made in view of the above-mentioned problems, and its object is to provide an ink jet textile printing method capable of suppressing bleeding, preventing ink overflow, and obtaining a high-quality print excellent in backside image delineability. is there.

  The above object of the present invention is achieved by the following configurations.

1. A copolymer containing a pigment, water, a surfactant, a fixing resin and a water-soluble solvent, and at least one of the fixing resins polymerized using an unsaturated vinyl monomer having a carboxyl group as a component was neutralized and dissolved with an amine. A water-soluble copolymer, which is an aqueous inkjet pigment ink containing glycol ethers or 1.2-alkanediols as a water-soluble solvent, and mainly has an average thickness of 20d (denier) or more and 100d (denier) A method for recording on a fabric for ink jet textile printing comprising the following polyester yarn, wherein the ink jet textile fabric is heated at 40 ° C. or higher and 90 ° C. or lower when recording, and the recording resolution is 360 dpi or higher and 1440 dpi or lower ( dpi represents the number of dots per 2.54 cm), and the ink droplet amount is 3.5 pl or more. 56pl or less, and the maximum ink application amount is 40 ml / m ² following conditions, ink-jet printing method characterized by recording the inkjet aqueous pigment ink to the fabric for ink jet printing.

  2. 2. The ink-jet printing method according to 1 above, wherein the water-based pigment ink for ink-jet further contains water-based dispersed polymer fine particles as the fixing resin.

  3. 3. The inkjet printing method according to 1 or 2 above, wherein the fabric for inkjet printing composed of the polyester yarn is not previously treated.

  According to the present invention, it was possible to provide an ink jet textile printing method capable of suppressing ink bleeding, preventing ink overflow, and obtaining an ink jet textile print excellent in backside image delineability.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

As a result of intensive studies in view of the above problems, the present inventor,
At least 1) pigments,
2) water,
3) surfactant,
4) As a fixing resin, a water-soluble copolymer obtained by neutralizing and dissolving a copolymer obtained by polymerizing an unsaturated vinyl monomer having a carboxyl group with an amine,
5) As a water-soluble solvent, using an inkjet aqueous pigment ink containing glycol ethers or 1.2-alkanediols,
6) Using a fabric for ink jet printing mainly composed of polyester yarn having an average thickness of 20 to 100d as a recording medium,
7) Heat the surface temperature of the inkjet textile fabric to 40-90 ° C,
8) The recording resolution is 360 dpi or higher and 1440 dpi or lower (dpi represents the number of dots per 2.54 cm),
9) When the ink droplet amount is 3.5 pl or more and 56 pl or less,
10) The ink-jet printing method is characterized in that the water-based pigment ink for ink-jet recording is recorded on a fabric for ink-jet printing under the condition that the maximum ink application amount is 40 ml / m ² or less. It has been found that an ink jet textile printing method capable of obtaining an ink jet textile print excellent in backside image descriptiveness can be obtained, and has reached the present invention.

  Hereinafter, the present invention will be described in detail.

  The inkjet textile printing method of the present invention uses an aqueous pigment ink for inkjet (hereinafter also referred to as an aqueous pigment ink or simply an ink) containing a specific water-soluble copolymer as a fixing resin, mainly a polyester having an average thickness of 20 to 100d. This is an ink-jet printing method in which recording is performed on specific ink printing conditions on a fabric for ink-jet printing (hereinafter, also simply referred to as a fabric). The water-based pigment ink increases in viscosity at the time of landing on the fabric, and decreases the fluidity of the ink. In addition, with the glycol ethers and surfactants used in combination, the ink penetrates quickly into the inside of the yarn, thereby preventing the overflow of the ink, and also preventing the ink from spreading through the gap between the yarns and spreading. In addition to realizing an image quality image, the color material can be sufficiently fixed to the fabric.

  About the phenomenon where said effect is exhibited, this inventor estimates as follows.

  That is, in the water-based pigment ink according to the present invention, the carboxyl group of the water-soluble copolymer is stably neutralized with an amine, and when landed on a heated fabric, a solvent such as moisture, an amine, etc. Evaporates to increase the concentration of the water-soluble copolymer. At the same time, the concentration of the water-soluble copolymer is further increased by volatilizing the amine used for neutralization. As a result, the viscosity of the ink is increased, so that the fluidity of the ink can be reduced, and overflow and bleeding of the landed ink can be prevented.

  Furthermore, since the amine as a neutralizing agent is volatilized, even if moisture is added to the recorded image again, the water-soluble copolymer is solidified without being redissolved in water, and the pigment is fixed. The present inventor believes that an effect of excellent image durability such as scratch resistance and water resistance is recognized.

(Water-soluble copolymer)
The water-soluble copolymer according to the present invention is designed and used having a hydrophilic component that is a carboxyl group and a hydrophobic component in an appropriate balance. At this time, the water-soluble copolymer according to the present invention to which water solubility is imparted by neutralizing the carboxyl group with a volatile base component sufficiently exhibits the above-described function. Examples of such water-soluble copolymers include acrylic resins, styrene-acrylic resins, acrylonitrile-acrylic resins, vinyl acetate-acrylic resins, polyurethane resins, and polyester resins.

  Examples of the hydrophobic monomer constituting the water-soluble copolymer according to the present invention include acrylic acid esters (for example, n-butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, etc.), methacrylic acid esters. (For example, ethyl methacrylate, butyl methacrylate, glycidyl methacrylate, etc.), styrene and the like.

  Examples of the hydrophilic monomer constituting the water-soluble copolymer according to the present invention include acrylic acid, methacrylic acid, and acrylamide.

  The acidic group such as a carboxyl group contained in the water-soluble copolymer according to the present invention needs to be partially or completely neutralized with an amine. Examples of the amine include ammonia, triethylamine, 2-dimethylaminoethanol, 2-di-n-butylaminoethanol, methyldiethanolamine, 2-amino-2-methyl-1-propanol, diethanolamine, triethanolamine, and 2-methyl. Aminoethanol or the like can be preferably used.

  In particular, neutralization with an amine having a boiling point of less than 200 ° C. is more preferable because the amine is easily volatilized at the time of drying, and the hydrophobicity is rapidly increased to contribute to the improvement of image durability.

  The water-soluble copolymer according to the present invention is preferably contained in an amount of 1.0% by mass or more and 10% by mass or less, more preferably 2.0% by mass or more and 7.0% by mass or less based on the total mass of the ink. It is. When the content of the water-soluble copolymer according to the present invention is 1.0% by mass or more, bleeding can be remarkably prevented and a high-quality image can be obtained. When the content is 10% by mass or less, the storage stability of the ink is remarkably good, stable emission is possible, and a print can be stably obtained over a long period of time.

  In addition, the water-soluble copolymer according to the present invention preferably has an acid value of 80 mgKOH / g or more and less than 300 mgKOH / g, but this significantly increases the viscosity of the water-soluble copolymer upon drying. In addition, the pigment solidifies more firmly after drying, and the fixability of the pigment is good. A more preferred acid value is about 90 to 250 mg KOH / g. The acid value defined in the present invention can be measured according to JIS K0070.

  The polymerization method of the water-soluble copolymer according to the present invention is preferably solution polymerization. As a molecular weight of the water-soluble copolymer according to the present invention, an average molecular weight of 3000 to 30000 can be preferably used, and more preferably 7000 to 20000.

  The Tg of the water-soluble copolymer according to the present invention is preferably about -30 ° C to 100 ° C, more preferably -10 ° C to 80 ° C.

(Water-soluble solvent)
One feature of the aqueous pigment ink for inkjet according to the present invention is that it contains glycol ethers or 1,2-alkanediols as a water-soluble solvent.

  By using glycol ethers and 1,2-alkanediols together with the water-soluble copolymer, these water-soluble solvents cause hydrophobic interaction with the pigment dispersion and the water-soluble copolymer. After the ink has landed on the heated fabric, the moisture decreases and acts more strongly as the concentration of glycol ethers and the like increases, resulting in an ink thickening effect. Therefore, it is considered that the bleeding prevention effect is remarkably exhibited by using the water-soluble polymer and glycol ethers in combination.

  On the other hand, the glycol ethers and the like are solvents having a relatively small surface tension, and have a synergistic effect with the surfactant to be used in combination with a fabric for ink jet printing composed of polyester yarn having an average thickness of 20 to 100d. Demonstrate sufficient affinity. As a result, the aqueous pigment ink quickly penetrates into the polyester yarn having a specific range of thickness as in the present invention, so that the phenomenon of spreading through the gap between the yarns is suppressed, and the pigment is applied to the fabric. The present inventor believes that it is sufficiently established.

  Examples of glycol ethers according to the present invention include ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monobutyl ether, triethylene glycol monobutyl ether, propylene glycol monopropyl ether, dipropylene glycol monomethyl ether, and tripropylene glycol monomethyl ether. Etc. Examples of 1,2-alkanediols include 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, and the like.

  The glycol ether or 1,2-alkanediol organic solvent according to the present invention is particularly preferably contained in an amount of 2 to 20% by mass with respect to the total mass of the ink from the viewpoint that the effects of the present invention are remarkably exhibited.

[Surfactant]
The surfactant according to the present invention is not particularly limited, and examples thereof include silicon surfactants, fluorine surfactants, and acetylene surfactants.

  The silicon surfactant is preferably a dimethylpolysiloxane whose side chain or terminal is polyether-modified (polyether-modified polysiloxane compound). For example, KF-351A and KF-642 manufactured by Shin-Etsu Chemical Co., Ltd. and Big Chemie BYK347, BYK348 and the like.

  In addition, the fluorine-based surfactant means a compound in which a part or all of the surfactant is substituted with fluorine in place of hydrogen bonded to carbon of a hydrophobic group of a normal surfactant. Of these, those having a perfluoroalkyl group in the molecule are preferred.

  Some of the fluorosurfactants are commercially available, for example, under the trade name Megafac F from Dainippon Ink Chemical Co., Ltd. and under the trade name Surflon from Asahi Glass Co., Ltd. EI Dupont Nemeras and Company, Inc. under the trade name Fluorad FC from Minnesota Mining and Manufacturing Company, and Monfloor from Imperial Chemical Industry Are sold under the trade name Zonyls, and under the trade name Licobet VPF from Farbeberke Hoechst.

  Examples of nonionic fluorosurfactants include Megafax 144D manufactured by Dainippon Ink and Surflon S-141 and 145 manufactured by Asahi Glass Co., and amphoteric fluorosurfactants. Examples of the agent include Surflon S-131 and 132 manufactured by Asahi Glass Co., Ltd.

  The acetylene surfactant that can be used in the present invention is an acetylene glycol surfactant, which has a triple bond in the molecule, a hydroxyl group and an alkyl group on the adjacent carbon atom, and In other words, a symmetrical structure is preferable. The acetylene glycol compound and acetylene alcohol compound that can be used in the present invention can be obtained as commercially available products, such as Surfynol, Orphine manufactured by Nissin Chemical Industry Co., Ltd., and acetylenol manufactured by Kawaken Fine Chemical Co., Ltd. It is done.

[Pigment]
Next, the pigment according to the present invention will be described.

  The pigment applicable to the present invention is not particularly limited as long as it can be stably dispersed in an aqueous system. A pigment dispersion dispersed with a polymer resin, a capsule pigment coated with a water-insoluble resin, a dispersion resin modified with a pigment surface is used. It is possible to select from self-dispersing pigments that can be dispersed without such. When emphasis is particularly placed on the storage stability of the ink, it is preferable to select a capsule pigment coated with a water-insoluble resin.

  When a pigment dispersion dispersed with a polymer resin is used, a polymer resin preferably used is a styrene-acrylic acid-alkyl acrylate copolymer, a styrene-acrylic acid copolymer, or a styrene-maleic acid copolymer. Polymer, styrene-maleic acid-acrylic acid alkyl ester copolymer, styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylic acid alkyl ester copolymer, styrene-maleic acid half ester copolymer, vinyl naphthalene-acrylic Resins such as acid copolymers, vinyl naphthalene-maleic acid copolymers, and the like.

  Various methods such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, and a paint shaker can be used as a pigment dispersion method.

  In order to prepare the pigment dispersion according to the present invention, it is preferable to use a centrifugal separator or a filter for the purpose of removing coarse particles of the pigment dispersion.

  The water-insoluble resin in the case of using a capsule pigment coated with a water-insoluble resin is a resin that is insoluble in weakly acidic or weakly basic water, and preferably has a solubility in an aqueous solution of pH 4 to 10. The resin is less than mass%.

  Such resins include acrylic, styrene-acrylic, acrylonitrile-acrylic, vinyl acetate, vinyl acetate-acrylic, vinyl acetate-vinyl chloride, polyurethane, silicon-acrylic, acrylic silicon, polyester Examples thereof include epoxy resins and epoxy resins.

  In the present invention, a resin prepared using a hydrophobic monomer and a hydrophilic monomer as constituent components can be used as the resin used for dispersing the pigment.

  Examples of the hydrophobic monomer include acrylic acid esters (for example, n-butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, etc.), methacrylic acid esters (for example, ethyl methacrylate, butyl methacrylate, glycidyl methacrylate). Etc.), styrene and the like.

  Examples of the hydrophilic monomer include acrylic acid, methacrylic acid, acrylamide and the like, and those having an acidic group such as acrylic acid can preferably be those neutralized with a base after polymerization.

  As molecular weight of resin, the thing of 3000-500000 can be used with the weight average molecular weight Mw. Preferably, the thing of 7000-200000 can be used.

  The Tg of the resin can be about −30 to 100 ° C., preferably about −10 to 80 ° C.

  As the polymerization method, solution polymerization or emulsion polymerization can be used. The polymerization may be performed separately from the pigment in advance, or may be performed by supplying a monomer into the system in which the pigment is dispersed.

  As a method for coating the pigment with the resin, various known methods can be used. Preferably, in addition to the phase inversion emulsification method and the acid precipitation method, the pigment is dispersed using a polymerizable surfactant, It is preferable to select from a method in which a monomer is supplied thereto and coating is performed while polymerizing. As a more preferable method, a water-insoluble resin is dissolved in an organic solvent such as methyl ethyl ketone, and after partially or completely neutralizing an acidic group in the resin with a base, a pigment and ion-exchanged water are added and dispersed. A production method in which an organic solvent is removed and water is added as necessary is preferable.

  The mass ratio of the pigment and the resin can be selected from 100/40 to 100/150 as a pigment / resin ratio. Particularly, 100/60 to 100/110 have good image durability, injection stability, and ink storage stability.

  The average particle diameter of the pigment particles coated with the water-insoluble resin is preferably about 80 to 150 nm from the viewpoint of ink storage stability and color development.

  The average particle diameter of the pigment particles can be determined by a commercially available particle size measuring instrument using a light scattering method, an electrophoresis method, a laser Doppler method, or the like. It is also possible to obtain a particle image with a transmission electron microscope on at least 100 particles and perform statistical processing on the image using image analysis software such as Image-Pro (manufactured by Media Cybernetics). Is possible.

  Further, as the self-dispersing pigment, commercially available products that have been surface-treated can be used, and examples thereof include CABO-JET200, CABO-JET300 (above, manufactured by Cabot Corporation), Bonjet CW1 (manufactured by Orient Chemical Industry Co., Ltd.) and the like. be able to.

  As the pigment that can be used in the present invention, conventionally known organic and inorganic pigments can be used. Examples include azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, perylene and perylene pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments. Examples include cyclic pigments, dye lakes such as basic dye lakes, and acid dye lakes, organic solvents such as nitro pigments, nitroso pigments, aniline black, and daylight fluorescent pigments, and inorganic pigments such as carbon black.

  Specific organic pigments are exemplified below.

  Examples of pigments for magenta or red include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.

  Examples of the orange or yellow pigment include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 128, C.I. I. And CI Pigment Yellow 138.

  Examples of pigments for green or cyan include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.

[Aqueous dispersion type polymer]
The ink according to the present invention can contain various compounds other than those described above. For example, as the resin for fixing the coloring material, it is preferable to contain water-based dispersed polymer fine particles in addition to the water-soluble copolymer according to the present invention as described above.

  The water-soluble copolymer according to the present invention functions to thicken the ink during drying to prevent bleeding, and the amine as a neutralizing agent volatilizes, so that it is difficult to be re-dissolved in moisture and has a pigment fixing property. Although it is excellent, it can contribute to the improvement of abrasion resistance by making the pigment fixing property stronger by further containing water-based dispersed polymer fine particles. Also, combined use with water-dispersible polymer fine particles controls the speed at which the ink is thickened, and the ink droplets at the time of landing are appropriately leveled to prevent unevenness on the image surface and improve image clarity. There is an advantage that it can be satisfied in combination with maintenance, suppression of bleeding, and pigment fixing property.

  The Tg of the water-based dispersed polymer fine particles is preferably 35 ° C. or higher in view of particularly exhibiting an image scratch resistance effect, and more preferably 49 ° C. or higher. The upper limit of Tg is not particularly limited, but is preferably about 100 ° C. or less because a flexible ink film can be obtained and cracking of an image due to bending of a printed matter can be suppressed.

  The acid value of the aqueous dispersion type polymer fine particles is preferably 44 mgKOH / g or more, and more preferably 60 mgKOH / g or more. The upper limit of the acid value is not particularly limited, but is preferably less than 110 mgKOH / g from the viewpoint of easily obtaining a more stable dispersion.

  The average particle size of the water-dispersible polymer fine particles is preferably 300 nm or less, more preferably 130 nm or less, from the viewpoint that there is no clogging in the nozzle of the ink jet recording head and a good gloss feeling is obtained. The lower limit of the average particle diameter is preferably 30 nm from the viewpoint of production stability of fine particles.

  The content of the water-based dispersed polymer fine particles is preferably 0.7% to 6%, particularly preferably 1% to 3% from the viewpoints of the fixing property of the color material and the storage stability of the ink.

  The aqueous dispersion type polymer fine particles may be used as it is or after treatment of a dispersion polymerized in an aqueous system, or a dispersion of a polymer polymerized in a solvent system may be used in an acrylic, It can be selected from urethane, styrene, vinyl acetate, vinylidene chloride, vinyl chloride, styrene-butadiene, styrene-acrylonitrile, polybutadiene, polyethylene, polyisobutylene, polyester, and the like.

  In addition, the water-based dispersed polymer particles are preferably soap-free dispersed polymer particles from the viewpoint of ejection stability. Particularly preferred aqueous dispersion polymer fine particles are self-dispersion dispersions of a copolymer obtained by polymerizing unsaturated vinyl having a carboxyl group as a monomer component. For example, acrylic monomers such as ethyl acrylate alone or acrylic Mechanically sheared after a dispersion obtained by emulsion polymerization or suspension polymerization of acrylic acid or maleic acid as a carboxylic acid monomer in a composition comprising an ethylenically unsaturated monomer that can be copolymerized with a monomer is swelled with alkali, and then mechanically sheared. Is an acrylic hydrosol obtained by dividing the particles. Among acrylic hydrosols, it is preferable to contain styrene in the monomer composition from the viewpoint of increasing the refractive index of the resin and obtaining high glossiness.

  As the acrylic hydrosol, Jonkrill (trademark) manufactured by Johnson Polymer Co., Ltd. is commercially available.

[Other solvents]
In addition to the water-soluble solvent according to the present invention, various liquid media can be used for the ink according to the present invention. As the liquid medium, a mixed solvent such as water and a water-soluble organic solvent is more preferably used. For example, alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, t-butanol, etc.), polyhydric alcohols (eg, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene) Glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol, etc.), amines (eg, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N- Ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine, tri Chirentetoramin, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine), amides (e.g., formamide, N, N-dimethylformamide, N, N- dimethylacetamide and the like) and the like.

[Inkjet textile fabric]
The ink-jet textile fabric according to the present invention is mainly composed of polyester yarn having an average thickness of 20 to 100d. When the thickness is this thickness, the aqueous pigment ink according to the present invention sufficiently penetrates into the yarn. Further, it is possible to remarkably suppress bleeding caused by diffusing a gap between yarns. More preferably, when the average thickness of the polyester yarn is 30 to 75d, it is possible to remarkably prevent ink overflow and bleeding, realize a high-quality image, and sufficiently fix the color material to the fabric. Can do. In the present invention, the polyester yarn having an average thickness of 20 to 100d mainly means that 60% or more of the fabric for inkjet printing is composed of polyester yarn having an average thickness of 20 to 100d, preferably 80% or more of the fabric for inkjet printing is composed of polyester yarn having an average thickness of 20 to 100d, and particularly preferably 90% or more of the fabric for inkjet printing has an average thickness of 20 to 100d. It is made of polyester yarn.

  The polyester yarn is a yarn formed by twisting polyester fibers. The polyester yarn is a synthetic fiber having an ester bond, and the polyester yarn has high tensile strength, friction strength, and heat resistance. High rate blending with fibers or the like may be performed.

  The polyester fiber constituting the polyester yarn according to the present invention is a condensation polymer of ethylene glycol and terephthalic acid, a condensation polymer of linear diol and terephthalic acid having 3 to 8 carbon atoms, or ethylene glycol, terephthalic acid and carbon number. It is preferably composed of fibers mainly containing a polycondensation product of 3 to 8 linear dicarboxylic acids, and in particular, fibers in which a linear alkylene group having 3 to 8 carbon atoms is introduced into the polyester main chain.

  The average thickness of the polyester fibers constituting the polyester yarn having the average thickness according to the present invention is not particularly limited, but is preferably 1 to 10d, and more preferably 2 to 7d. Polyester yarn having an average thickness of 20 to 100d produced by twisting such polyester fibers forms an appropriate state of fiber entanglement, and thereby contains the aqueous pigment ink according to the present invention inside the yarn. As a result, the fixing resin in which the neutralizing agent is volatilized and the pigment are entangled well, so that the ink is prevented from diffusing and bleeding through the gap between the yarns, and a good image without overflow can be formed.

  In addition, the ink jet printing method of the present invention shows the effect of the present invention remarkably even in the case of a fabric that has not been subjected to pre-treatment in advance. The advantage of high-quality image formation can be exhibited.

  That is, in an ink jet printing method in which an ink having a remarkably low viscosity is used as compared with a conventional printing paste, and only a necessary minimum amount of coloring material is applied to the fabric to form an image by dot expression, Compared with the image forming method, the physical condition of the fabric is extremely limited. However, according to the ink jet textile printing method of the present invention, by using an aqueous pigment ink containing a specific fixing resin, the average of polyester yarn By using a fabric with a controlled thickness, a high-quality image can be easily formed without pre-processing for printing.

(Printing conditions)
In order to obtain a high-quality print in a fabric for ink jet printing composed of polyester yarn having a specific thickness according to the present invention, each dot itself is made finer and the number of dots per inch (2.54 cm) (this) However, in order to achieve a desired dot size, the amount of one ink droplet ejected from each nozzle at a time is determined. come.

  At this time, if the recording resolution is too large when the amount of droplets is constant, even if the aqueous pigment ink according to the present invention is used, ink overflow on the fabric cannot be prevented, and the recording resolution is low. If it is too high, it is difficult to form a high-quality print.

  On the other hand, if the amount of ink droplets is too small when the number of dots is constant, even if printing is performed on the fabric according to the present invention, a phenomenon called banding that creates gaps between dots on the fabric is caused, which is undesirable in terms of print quality. Also, if the amount of ink droplets is too large, ink overflow on the fabric cannot be prevented.

  The following relationship is established among the recording resolution, the ink droplet amount, and the maximum ink application amount.

I = {(D ² × L) / (0.0254 ² )} × (10 ⁻⁹ )
In the formula, D represents the recording resolution (dpi), L represents the ink droplet amount (pl), and I represents the applied amount of ink per color (ml / m ² ).

For example, when the recording resolution is 720 dpi × 720 dpi and the ink droplet amount is 14 pl, the amount of ink applied per color is 11 ml / m ² when ejected so that the droplets are arranged on all pixels. If a black solid image is formed using three colors of yellow ink and cyan ink, 33 ml / m ² ink is applied to the fabric according to the present invention, and the aqueous pigment ink according to the present invention constitutes the fabric. The high-quality print is formed by penetrating into the polyester yarn having a specific thickness, suppressing the phenomenon of bleeding through the gap between the yarns, and preventing ink overflow. Furthermore, if ink-jet textile printing is performed using the fabric according to the present invention and water-based pigment ink, even when black ink of about 6 ml / m ^{2 is applied} to form a black solid image, bleeding is suppressed and ink overflow is prevented. Prevented high-quality prints can be formed.

Therefore, in the recording method of the present invention, the maximum ink application amount is 40 ml / m ² or less, the recording resolution is 360 dpi or more and 1440 dpi or less, and the ink droplet amount is 3.5 pl or more and 56 pl or less. In this case, using the aqueous pigment ink containing the specific water-soluble copolymer according to the present invention, a fabric composed of polyester yarn having a specific thickness is heated to perform inkjet printing recording. Thus, it is possible to obtain a high-quality print without banding that suppresses bleeding and prevents ink overflow.

  Temporarily, using the aqueous pigment ink containing a fixing resin other than the specific water-soluble copolymer according to the present invention, according to the ink-jet printing method of the present invention, the recording resolution, the ink droplet amount, and the maximum ink according to the present invention. Even if printing is performed with the value of the applied amount, bleeding and ink overflow cannot be prevented.

[Heating fabric]
One of the features of the ink-jet printing method of the present invention is that the fabric is heated to 40 to 90 ° C. for printing.

  By heating the fabric, the drying and thickening speed of the ink is remarkably improved, and high image quality is obtained. Also, the durability of the image is improved. If it is 40 ° C. or higher, the image quality is sufficient and sufficient image durability is obtained, and the drying time is relatively short. On the other hand, when the temperature is 90 ° C. or lower, it is possible to ensure stable ink ejection and stably print. More preferably, the recording surface temperature of the recording medium is 40 to 60 ° C. As a heating method, it is possible to select a method in which a heating heater is incorporated in the recording medium conveyance system or the platen member and heated from the lower side of the recording medium in a contact manner, or a method of heating in a non-contact manner from the lower side or the upper side by a lamp or the like. Moreover, in this invention, it can also select preferably to heat to 120-180 degreeC as a post-process after printing, and to make a final image.

[Inkjet head]
The ink-jet head used in the ink-jet printing method of the present invention may be an on-demand method or a continuous method, and as an ejection method, an electro-mechanical conversion method (for example, a single cavity type, a double cavity type, a bender type). , Piston type, shear mode type, shared wall type, etc.), and any discharge method such as an electro-thermal conversion method (for example, thermal ink jet type, bubble jet (registered trademark) type) may be used.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

<< Production of Fabric >>
[Production of Fabric A]
A 100% polyester woven fabric was produced using polyester filament yarn having an average thickness of 50d made of polyester fibers having an average thickness of 2d.

[Production of Fabric B]
A woven fabric of 100% polyester was prepared using a polyester filament yarn having an average thickness of 70d made of polyester fibers having an average thickness of 4d.

[Production of Fabric C]
A 100% polyester woven fabric was produced using polyester filament yarn having an average thickness of 30d made of polyester fibers having an average thickness of 2d.

[Production of Fabric D]
A woven fabric of 100% polyester was prepared using polyester filament yarn having an average thickness of 10d made of polyester fibers having an average thickness of 0.5d.

[Production of Fabric E]
A polyester 100% polyester woven fabric made of polyester fibers having an average thickness of 15d was used to produce a 100% polyester woven fabric.

<< Preparation of pigment dispersion >>
[Preparation of Pigment Dispersion-C]
As a pigment dispersant, 3 parts of a styrene-acrylic acid copolymer (John Cryl 678, molecular weight 8500, acid value 215), 1.3 parts of dimethylaminoethanol, and 80.7 parts of ion-exchanged water are stirred and mixed at 70 ° C to dissolve. did.

  Next, C.I. I. After adding 15 parts of Pigment Blue 15: 3 and premixing, the mixture was dispersed using a sand grinder filled with 50% by volume of 0.5 mm zirconia beads, and a pigment dispersion having a cyan pigment content of 15% -C was prepared.

[Preparation of Pigment Dispersion-Y, M, Bk]
In the preparation of Pigment Dispersion-C, cyan pigment C.I. I. Instead of CI Pigment Blue 15: 3, C.I. I. Pigment Yellow-74, C.I. I. Pigment Dispersion-Y, Pigment Dispersion-M, and Pigment Dispersion-Bk were prepared in the same manner except that Pigment Red 122 and carbon black were used as the black pigment.

<Synthesis of water-soluble copolymer>
[Synthesis of water-soluble copolymer 1]
50 g of methyl ethyl ketone was added to a flask equipped with a dropping funnel, a nitrogen introducer, a reflux condenser, a thermometer and a stirrer, and heated to 75 ° C. while bubbling nitrogen.

  Thereto, a mixture composed of 80 g of n-butyl methacrylate, 20 g of acrylic acid, 50 g of methyl ethyl ketone, and 500 mg of a polymerization initiator (AIBN) was added dropwise from a dropping funnel over 3 hours. After the dropwise addition, the mixture was further refluxed for 6 hours. After allowing to cool, the mixture was heated under reduced pressure, and methyl ethyl ketone was distilled off to obtain a polymer residue.

  In 450 ml of ion-exchanged water, dimethylaminoethanol corresponding to 1.05 moles of acrylic acid added as a monomer was dissolved, and the polymer residue was added and dissolved therein. Next, the concentration was adjusted with ion-exchanged water to obtain an aqueous solution of water-soluble copolymer 1 (acid value 117 mgKOH / g) having a water-soluble copolymer content of 20%.

[Synthesis of water-soluble copolymer α for comparison]
50 g of methyl ethyl ketone was added to a flask equipped with a dropping funnel, a nitrogen introducer, a reflux condenser, a thermometer and a stirrer, and heated to 75 ° C. while bubbling nitrogen.

  Thereto, a mixture of 80 g of n-butyl methacrylate, 20 g of acrylic acid, 50 g of methyl ethyl ketone, and 500 mg of a polymerization initiator (AIBN) was dropped from a dropping funnel over 3 hours. It heated and refluxed for 6 hours after dripping. After allowing to cool, the mixture was heated under reduced pressure to distill off methyl ethyl ketone to obtain a polymer residue.

  Sodium hydroxide equivalent to 1.05 moles of acrylic acid added as a monomer was dissolved in 450 ml of ion-exchanged water, and the polymer residue was dissolved therein. The concentration was adjusted with ion-exchanged water to obtain an aqueous solution of water-soluble copolymer α (acid value 117 mgKOH / g) having a water-soluble copolymer content of 20%.

<Preparation of ink set>
[Preparation of ink set 1: the present invention]
(Preparation of ink C1)
While stirring 46.6 parts of the pigment dispersion-C prepared above, the aqueous solution 15.0 of the water-soluble copolymer 1 having a content of the water-soluble copolymer having a hydrophobic monomer as a polymerization component is 20%. Then, the following compounds were sequentially added to prepare an ink composition, which was filtered through a 0.8 μm filter to obtain an ink C1.

Pigment dispersion-C 46.6 parts Aqueous solution of water-soluble copolymer 1 (water-soluble copolymer content: 20%) 15.0 parts PDX-7667 (manufactured by BASF, acrylic particle content: 45%) 2 .9 parts Triethylene glycol monobutyl ether 10.0 parts 1,2-hexanediol 5.0 parts Diethylene glycol 11.2 parts Silicone surfactant: KF-351A (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.6 parts Ion-exchanged water Was added to prepare 100 parts in total. The content of the water-soluble copolymer 1 in the ink C11 is 3.0% by mass, and the content of the acrylic particles is 1.3% by mass.

(Preparation of ink Y1, M1, Bk1)
Ink Y1, ink M1, and ink Bk1 were prepared in the same manner as in the preparation of ink C1, except that pigment dispersions Y, M, and Bk were used instead of pigment dispersion C.

  Ink set 1 was composed of ink C1, ink Y1, ink M1 and ink Bk1 prepared as described above.

[Preparation of ink set 2: the present invention]
In the preparation of the ink C1, the ink Y1, the ink M1 and the ink Bk1 constituting the ink set 1, the ink C2 in the same manner except that the content of the water-soluble copolymer 1 was changed to 1.0% by mass. Ink Y2, ink M2, and ink Bk2 were prepared and used as ink set 2.

[Preparation of ink set 3: Comparative example]
Ink C3 was prepared in the same manner as in the preparation of ink C1, ink Y1, ink M1 and ink Bk1 constituting ink set 1, except that water-soluble copolymer 1 was changed to the same amount of water-soluble copolymer α. Ink Y3, Ink M3, and Ink Bk3 were prepared and used as Ink Set 3.

[Preparation of ink set 4: the present invention]
In the preparation of ink C1, ink Y1, ink M1 and ink Bk1 constituting the ink set 1, the content of the water-soluble copolymer 1 was changed from 3.0% by mass to 4.0% by mass, and PDX Ink C4, Ink Y4, Ink M4, and Ink Bk4 were prepared in the same manner except for -7667 (acrylic particles), and this was designated as Ink Set 4.

Example 1
(Image printing)
Inkjet recording was performed using an inkjet recording apparatus capable of four-color printing in which four piezo-type heads were arranged in parallel. In the ink jet recording apparatus, the fabric can be heated from below by a contact heater. In addition, an ink emptying position and a blade wipe type maintenance unit are provided at the head storing position, and a mechanism capable of cleaning the head at an arbitrary frequency is provided.

Each head of the inkjet recording apparatus is loaded with each of the ink sets 1 to 4 (Y, M, C, Bk) prepared above, recording resolution 720 dpi × 720 dpi, droplet amount 14 pl, head transport speed 200 mm / sec (both Gray print images 11 to 14 and character images 11 to 14 were formed on the produced fabric A (average thickness 50d) at 100 duty under the conditions of the fabric heating temperature of 60 ° C. The maximum ink application amount at this time was 33 ml / m ² .

[Evaluation of formed image]
(Evaluation of overflow)
In the formed gray solid image, the state of occurrence of image unevenness caused by ink overflow was visually observed, and overflow (unevenness) was evaluated according to the following criteria.

◎: Uniform, non-uniformity, clear image ○: Slightly weak unevenness is observed, but acceptable image quality x: Strong unevenness is observed, and sharpness is poor It is an image (evaluation of bleeding)
In the image of the boundary area with the white background (unprinted portion) of the gray character image formed as described above, the presence or absence of irregular disturbance due to bleeding was visually observed, and bleeding was evaluated according to the following criteria.

A: Almost no image distortion in the boundary area B: Slight image distortion in the boundary area is recognized, but the image quality is acceptable for practical use X: Strong image disturbance occurs in the boundary area, and practical use Table 1 shows the results obtained as described above.

  As is apparent from the results shown in Table 1, by using the ink set having the configuration defined in the present invention, the image formed on the fabric was prevented from overflowing and the high-quality image with suppressed bleeding compared to the comparative example. It can be seen that

Example 2
(Image printing)
Using the same ink jet recording apparatus as described in Example 1, each of the heads of the ink jet recording apparatus was loaded with the prepared ink set 1 (Y1, M1, C1, Bk1), and the recording resolution was 720 dpi × 720 dpi, Under the conditions of a droplet amount of 14 pl, a head conveyance speed of 200 mm / sec (bidirectional printing), and a fabric heating temperature of 60 ° C., each of the fabrics A to E produced above has a 100 duty and a gray solid image 21 to 25. And character images 21 to 25 were formed. The maximum ink application amount at this time was 33 ml / m ² .

[Evaluation of formed image]
Each formed image was evaluated for overflow (unevenness) and bleeding in the same manner as in the method described in Example 1, and the results obtained are shown in Table 2.

  As is apparent from the results shown in Table 2, by using a fabric having an average thickness in the range specified in the present invention, image formation is performed under the ink and printing conditions of the present invention, thereby preventing overflow and bleeding. It can be seen that a high-quality image can be obtained. When the fabrics D and E of the comparative example were used, blurring occurred particularly in the boundary area between the printing part and the non-printing part, and a clear image could not be obtained.

Example 3
(Image printing)
Using the same ink jet recording apparatus as described in Example 1, each of the heads of the ink jet recording apparatus was loaded with the ink set 1 prepared above (Y1, M1, C1, Bk1), and the recording resolution was 720 dpi × 720 dpi, Under the conditions of a droplet amount of 14 pl and a head conveyance speed of 200 mm / sec (bidirectional printing), the heating temperature of the fabric is 30 ° C., 40 ° C., 60 ° C., 85 ° C., 100 ° C. The gray solid images 31 to 35 and the character images 31 to 35 were formed at 100 duty. The maximum ink application amount at this time was 33 ml / m ² .

[Evaluation of formed image]
About each formed image, it carried out similarly to the method as described in Example 1, and evaluated the overflow (unevenness) and bleeding, and the back surface image description property according to the following method.

(Evaluation of back side image description)
The created gray solid image was visually observed from the front surface (printing surface side) side and the back surface side, and the back surface image drawability was evaluated according to the following criteria.

◎: Even when observed from the back side, a sufficiently high density image is formed. ○: When viewed from the back side, the density is lower than the observed image from the front side. Formed x: Observed from the back side, the density is mottled, and a low-quality image is formed Table 3 shows the results obtained as described above.

  As is apparent from the results shown in Table 3, by heating and drawing the fabric in the temperature range specified in the present invention, an image excellent in backside image descriptiveness can be obtained while preventing overflow and suppressing bleeding. I understand that.

Example 4
(Image printing)
Using an ink jet recording apparatus similar to that described in Example 1, image formation was performed under the following printing conditions of 41 to 46, and evaluation of overflow (unevenness) and bleeding was performed in the same manner as in the method described in Example 1. Went.

(Printing condition 41: the present invention)
Using the inkjet recording apparatus described in Example 1, the above-mentioned preparation was performed on fabric A at a recording resolution of 720 dpi × 720 dpi, a droplet amount of 14 pl, a head conveyance speed of 200 mm / sec (bidirectional printing), and a fabric heating temperature of 60 ° C. Using the inks C1, M1, and Y1 of the ink set 1, a gray solid image and a character image were formed with each color ink at 100 duty. The maximum ink application amount at this time was 33 ml / m ² .

(Printing condition 42: the present invention)
The inkjet recording apparatus described in Example 1 was used, and the inkjet recording apparatus having the recording resolution of 360 dpi × 360 dpi, the droplet amount of 56 pl, the head conveyance speed of 200 mm / sec (bidirectional printing), and the fabric heating temperature of 60 ° C. was used. Then, using the inks C1, M1, and Y1 of the ink set 1 on the fabric A, a gray solid image and a character image were formed with each color ink at 100 duty. The maximum ink application amount at this time was 33 ml / m ² .

(Printing condition 43: the present invention)
Ink set on fabric A using the inkjet recording apparatus described in Example 1, recording resolution 1440 dpi × 1440 dpi, droplet volume 3.5 pl, head transport speed 200 mm / sec (bidirectional printing), fabric heating temperature 60 ° C. Using a single ink C1, M1, and Y1, a gray solid image and a character image were formed with each color ink at 100 duty. The maximum ink application amount at this time was 33 ml / m ² .

(Printing condition 44: Comparative example)
Using the inkjet recording apparatus described in Example 1, recording resolution 720 dpi × 720 dpi, droplet volume 84 pl, head transport speed 200 mm / sec (bidirectional printing), fabric heating temperature 60 ° C., and fabric heating temperature 60 ° C. Using the inks C1, M1, and Y1, gray solid images and character images were formed with each color ink at 100 duty.

(Printing condition 45: the present invention)
In the printing condition 41, the inks C1, M1, Y1, and Bk1 of the ink set 1 are used, the inks C1, M1, and Y1 are each 100 duty, and the ink Bk1 is 50 duty and a gray solid image and a character image. Formed. The maximum ink application amount at this time was 38 ml / m ² .

(Printing condition 46: the present invention)
Under the printing condition 41, using the inks C1, M1, Y1, and Bk1 of the ink set 1, a gray solid image and a character image were formed with each color ink at 100 duty. The maximum ink application amount at this time was 44 ml / m ² .

[Evaluation of formed image]
Each formed image was evaluated for overflow (unevenness) and bleeding in the same manner as in the method described in Example 1, and the obtained results are shown in Table 4.

  As is clear from the results shown in Table 4, by using the ink and fabric of the present invention and printing under the conditions specified in the present invention, it is possible to prevent overflow and suppress bleeding, and to achieve an excellent high quality image. It can be seen that In contrast to the printing condition 41, the printing condition 42 slightly reduced the sharpness of the image. Also, the printing condition 43 required a little time for image formation as compared with the printing condition 41.

Claims (3)

A copolymer containing a pigment, water, a surfactant, a fixing resin and a water-soluble solvent, and at least one of the fixing resins polymerized using an unsaturated vinyl monomer having a carboxyl group as a component was neutralized and dissolved with an amine. A water-soluble copolymer, which is an aqueous inkjet pigment ink containing glycol ethers or 1.2-alkanediols as a water-soluble solvent, and mainly has an average thickness of 20d (denier) or more and 100d (denier) A method for recording on a fabric for ink jet textile printing comprising the following polyester yarn, wherein the ink jet textile fabric is heated at 40 ° C. or higher and 90 ° C. or lower when recording, and the recording resolution is 360 dpi or higher and 1440 dpi or lower ( dpi represents the number of dots per 2.54 cm), and the ink droplet amount is 3.5 pl or more. 56pl or less, and the maximum ink application amount is 40 ml / m ² following conditions, ink-jet printing method characterized by recording the inkjet aqueous pigment ink to the fabric for ink jet printing. 2. The ink-jet printing method according to claim 1, wherein the water-based ink pigment ink further contains water-based dispersed polymer fine particles as the fixing resin. The inkjet textile printing method according to claim 1 or 2, wherein the textile for inkjet textile printing constituted by the polyester yarn has not been processed beforehand.