Inkjet ink composition for printing

Abstract

To provide an ink composition with a circulation mechanism used for a printer, which is high in color development, fastness, and clogging resistance.SOLUTION: The inkjet ink composition for printing used by being discharged from a recording head by an inkjet method contains a water soluble dye and organic solvents. A total content of the organic solvent is 15.0 mass% or less with respect to a total amount of the ink composition, a content of a high-boiling organic solvent of a standard boiling point of 290.0°C or higher among the organic solvents is 3.0 mass% or less with respect to the total amount of the ink composition, and a content of the water soluble dye is 5.0 mass% or less with respect to the total amount of the ink composition. The recording head has a nozzle for discharging the ink composition, a pressure chamber for applying pressure to the ink composition, and a circulation path which enables circulation of the ink composition in the recording head.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an inkjet ink composition for textile printing, a recording head set, an inkjet recording method, and an inkjet recording apparatus. [Background technology]

[0002] Inkjet recording methods are capable of recording high-resolution images with relatively simple equipment and have been rapidly developing in various fields. In the process, various studies have been conducted on ejection stability, etc. For example, Patent Document 1 discloses an inkjet recording device with the objective of providing an inkjet device that has excellent clogging recovery properties and is capable of forming high-density images with little bleeding. The inkjet recording device includes an ink composition and a recording head having nozzles for ejecting the ink composition, wherein the ink composition contains a water-soluble dye, a water-soluble organic solvent, and water, and the content of the water-soluble dye is 10% by mass or more relative to the total amount of the ink composition. The recording head includes the nozzles for ejecting the ink composition, a pressure chamber to which the ink composition is supplied, and a circulation flow path that allows the ink composition to circulate in the pressure chamber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-45926 Summary of the Invention [Problem to be solved by the invention]

[0004] As an ink composition to be used in a printer equipped with a circulation mechanism such as that described in Patent Document 1, an ink composition having better color development, fastness, and clogging resistance is desired. [Means for solving the problem]

[0005] The inkjet ink composition for textile printing of the present invention comprises: An inkjet ink composition for textile printing that is ejected from a recording head by an inkjet method, Contains a water-soluble dye and an organic solvent, the total content of the organic solvents is 15.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of high-boiling organic solvents having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, The recording head has a nozzle that ejects the inkjet ink composition for textile printing, a pressure chamber that applies pressure to the inkjet ink composition for textile printing, and a circulation flow path that allows the inkjet ink composition for textile printing supplied to the recording head to circulate within the recording head.

[0006] The recording headset of the present invention comprises: A recording headset comprising an inkjet ink composition for textile printing and a recording head, the inkjet ink composition for textile printing contains a water-soluble dye and an organic solvent, the total content of the organic solvents is 15.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of high-boiling organic solvents having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, The recording head has a nozzle that ejects the inkjet ink composition for textile printing, a pressure chamber that applies pressure to the inkjet ink composition for textile printing, and a circulation flow path that allows the inkjet ink composition for textile printing supplied to the recording head to circulate within the recording head.

[0007] The inkjet recording method of the present invention comprises: a deposition step of ejecting the inkjet ink composition for textile printing from a recording head and depositing it on a recording medium, The inkjet ink composition for textile printing contains a water-soluble dye and an organic solvent, the total content of the organic solvents is 15.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of high-boiling organic solvents having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, The recording head has a nozzle that ejects the inkjet ink composition for textile printing, a pressure chamber that applies pressure to the inkjet ink composition for textile printing, and a circulation flow path that allows the inkjet ink composition for textile printing supplied to the recording head to circulate within the recording head.

[0008] The inkjet recording apparatus of the present invention comprises: An inkjet recording apparatus comprising: an inkjet ink composition for textile printing containing a water-soluble dye and an organic solvent; and a recording head, 15.0% by mass or less of the total amount of the ink composition; the content of high-boiling organic solvents having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, The recording head has a nozzle that ejects the inkjet ink composition for textile printing, a pressure chamber that applies pressure to the inkjet ink composition for textile printing, and a circulation flow path that allows the inkjet ink composition for textile printing supplied to the recording head to circulate within the recording head. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing a line-type inkjet printing apparatus according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic diagram illustrating the configuration of a print head that can be used in the present embodiment. [Figure 3A] 1 is a table showing the compositions of inks A1 to I1. [Figure 3B] 1 is a table showing the compositions of inks J1 to R1. [Figure 3C] 1 is a table showing the compositions of inks S1 to X1, A2, B2, F2, and M2. [Figure 3D] 1 is a table showing the evaluation results of print density and drying property. [Figure 3E] 10 is a table showing evaluation results of robustness. [Figure 4A] 1 is a table showing the compositions of inks A3 to H3. [Figure 4B] 1 is a table showing the compositions of inks I3 to P3. [Figure 4C] 10 is a table showing the compositions of inks Q3 to U3, A4, B4, F4, and O4. [Figure 4D] 1 is a table showing the evaluation results of print density and drying property. [Figure 4E] 10 is a table showing evaluation results of robustness. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings as necessary, but the present invention is not limited to this, and various modifications are possible without departing from the spirit of the present invention. In the drawings, the same elements are given the same reference numerals, and redundant explanations will be omitted. Furthermore, positional relationships such as up, down, left, and right will be based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0011] 1. Inkjet ink composition for textile printing The inkjet ink composition for textile printing of this embodiment (hereinafter also simply referred to as "ink composition") is a composition for inkjet printing used by being ejected from a recording head by an inkjet method, and contains a water-soluble dye and an organic solvent, wherein the total content of the organic solvents is 15.0 mass % or less relative to the total amount of the inkjet ink composition for textile printing, the content of high-boiling point organic solvents having a normal boiling point of 290.0°C or higher is 3.0 mass % or less relative to the total amount of the inkjet ink composition for textile printing, and the content of the water-soluble dye is 5.0 mass % or more relative to the total amount of the inkjet ink composition for textile printing, and the recording head has a nozzle for ejecting the inkjet ink composition for textile printing, a pressure chamber for applying pressure to the inkjet ink composition for textile printing, and a circulation flow path for allowing the inkjet ink composition for textile printing supplied to the recording head to circulate within the recording head.

[0012] The ink jet ink composition for textile printing of this embodiment is ejected from a predetermined recording head having a circulation flow path, so first, a recording head having a circulation flow path and a recording apparatus equipped with the same will be described.

[0013] 1.1. Recording device The recording apparatus used in this embodiment includes the inkjet ink composition for textile printing and the recording head described above. The recording head has nozzles for ejecting the ink composition, pressure chambers for applying pressure to the ink composition, and a circulation flow path that allows the ink composition supplied to the recording head to circulate.

[0014] As an example of a recording apparatus, a schematic side view of a line printer (inkjet recording apparatus 100) is shown in Fig. 1. As shown in Fig. 1, the line printer includes a recording medium feeding section 110, a conveying section 120, a recording section 130, and a discharging section 150. It may also include a drying section 140.

[0015] Here, the feeding unit 110 feeds the recording medium F to the conveying unit 120, and the conveying unit 120 conveys the recording medium F sent from the feeding unit 110 to the recording unit 130, the drying unit 140, and the discharging unit 150. Specifically, the conveying unit 120 has feed rollers and conveys the sent recording medium F in the feed direction Y.

[0016] The recording unit 130 also includes a recording head 131 that ejects the ink composition onto the recording medium F sent from the transport unit 120. Although one inkjet head is shown in FIG. 1, the number of inkjet heads is not limited to this, and the recording unit 130 may include multiple inkjet heads depending on the type of composition.

[0017] In the case of a line printer, the print head 131 is provided with a line head in which nozzles are arranged over a length equal to or greater than the print width of the print medium, and the head is fixed without (almost) moving, and prints on the print medium in one pass (single pass). A pass is also called a scan.

[0018] Drying section 140 is used to dry the composition adhered to the recording medium as needed, and has drying section 141 (platen heater) provided opposite recording section 130, and drying section 142 provided downstream of recording section 130. Furthermore, discharge section 150 is provided so that the recorded matter can be discharged to the outside of the line printer.

[0019] Furthermore, although not shown, in the case of a serial printer, a recording head having a length smaller than the width of the recording medium is provided, and the recording head moves to perform recording in multiple passes (multi-pass). In addition, in a serial printer, the recording head is mounted on a carriage that moves in a predetermined direction, and the head moves in conjunction with the movement of the carriage, thereby ejecting the composition onto the recording medium. In this way, recording is performed in two or more passes (multi-pass). A pass is also called a main scan. A sub-scan is performed to transport the recording medium between passes. In other words, main scans and sub-scans are performed alternately.

[0020] Furthermore, the inkjet recording apparatus of this embodiment is not limited to the above-mentioned line type printer, but may also be the above-mentioned serial type printer.

[0021] 1.1.1. Recording head An example of a recording head is shown in Figure 2. As shown in Figure 2, the recording head 131 has a nozzle 1 that ejects an ink composition, a pressure chamber 2 that applies pressure to the ink composition, and a circulation channel 3 that allows the ink composition supplied to the recording head to circulate. In the example of Figure 1, the nozzle 1 and the pressure chamber 2 are in communication with each other via a communication channel 4.

[0022] The nozzle 1 is a through-hole that ejects the ink composition. More specifically, the nozzle 1 is a through-hole formed in a nozzle plate. The nozzle plate has a plurality of nozzles formed therein, and a pressure chamber 2 is provided for each of the nozzles. A pressure chamber 2 is formed individually for each nozzle 1. The ink composition is supplied to the pressure chamber 2, and when the pressure in the pressure chamber 2 changes due to a pressure generating means (not shown), part of the composition flowing in the communication channel 4 is ejected from the nozzle 1 to the outside, and the remaining part flows into the circulation channel 3.

[0023] The path of the circulation flow path 3 is not particularly limited, but the flow path can be configured so that the composition that has flowed into the circulation flow path 3 is supplied to the pressure chamber 2. The composition that has flowed into the circulation flow path 3 does not necessarily have to be re-supplied to the same pressure chamber 2, but may be supplied to a pressure chamber 2 corresponding to another nozzle. Furthermore, all of the flow paths of the circulation flow path 3 do not have to be inside the recording head 131, and some of the flow paths may be outside the recording head 131 as long as the flow path is configured so that the composition that has flowed out of the pressure chamber 2 is supplied to the pressure chamber 2 again.

[0024] This makes it possible to circulate the ink composition within the recording head 131. Circulating the ink composition prevents the ink composition from solidifying or thickening in the vicinity of the nozzles, making it possible to maintain fluidity and improve ejection stability and clogging recovery. Furthermore, even if there are differences in the usage rate and nozzle position for each nozzle, clogging due to the composition for each nozzle can be suppressed.

[0025] The recording head 131 may have a heating unit for heating the ink composition in the head. The installation location of such a heating unit is not particularly limited as long as it is capable of heating the composition in the circulation flow path including the pressure chamber 2 and the circulation flow path 3, and it may be provided, for example, in the recording head or the ink flow path. Furthermore, when a heating unit is provided in the recording head, the heating unit may be provided in either the pressure chamber or the circulation flow path. Furthermore, in the inkjet recording device of this embodiment, the ink composition is preferably filled in the ink flow path or the ink tank.

[0026] 1.2.Water-soluble dyes The water-soluble dye is not particularly limited, and examples thereof include acid dyes, reactive dyes, and direct dyes. The dyes may be used alone or in combination of two or more.

[0027] The acid dye is not particularly limited, but examples thereof include CI Acid Yellow, CI Acid Red, CI Acid Blue, CI Acid Orange, CI Acid Violet, and CI Acid Black.

[0028] The direct dye is not particularly limited, but examples thereof include CI Direct Yellow, CI Direct Red, CI Direct Blue, CI Direct Orange, CI Direct Violet, and CI Direct Black.

[0029] The reactive dye is not particularly limited, but examples thereof include CI Reactive Yellow, CI Reactive Red, CI Reactive Blue, CI Reactive Orange, CI Reactive Violet, and CI Reactive Black.

[0030] The total content of water-soluble dyes is 5.0% by mass or more, preferably 7.5% by mass or more, 10% by mass or more, 12.5% ​​by mass or more, 15% by mass or more, 17.5% by mass or more, 22.5% by mass or more, 25% by mass or more, or even more than 25% by mass, relative to the total amount of the inkjet ink composition for textile printing. Furthermore, the total content of water-soluble dyes is preferably 40% by mass or less, 35% by mass or less, or 30% by mass or less, relative to the total amount of the inkjet ink composition for textile printing. When the total content of water-soluble dyes is 5.0% by mass or more, color development tends to be further improved.

[0031] The water-soluble dye may contain two or more dyes. This allows for the ink to have complementary colors, such as composite black, which further improves color development. Considering color development, the dye content increases. However, in this embodiment, the use of a circulation head allows for a reduction in the amount of humectant added to the ink composition, allowing for an increase in the amount of dye.

[0032] 1.3.Organic Solvents The water-soluble organic solvent is not particularly limited, and examples thereof include glycol solvents, polyhydric alcohol solvents, glycol ether solvents, and nitrogen-containing solvents. The water-soluble organic solvents may be used alone or in combination of two or more.

[0033] The glycol solvent is not particularly limited, but examples thereof include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol, and 3-methyl-1,5-pentanediol.

[0034] The polyhydric alcohol solvent is not particularly limited, but an example thereof is glycerin.

[0035] The glycol ether solvent is not particularly limited, but examples thereof include ethylene glycol mono(di)propyl ether, diethylene glycol mono(di)propyl ether, ethylene glycol mono(di)butyl ether, diethylene glycol mono(di)methyl ether, diethylene glycol mono(di)ethyl ether, diethylene glycol mono(di)butyl ether, triethylene glycol mono(di)butyl ether, diethylene glycol mono(di)butyl ether, propylene glycol mono(di)methyl ether, propylene glycol mono(di)ethyl ether, propylene glycol mono(di)butyl ether, propylene glycol mono(di)propyl ether, propylene glycol mono(di)butyl ether, dipropylene glycol mono(di)butyl ether, dipropylene glycol mono(di)propyl ether, diethylene glycol ethyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol dimethyl ether.

[0036] The nitrogen-containing solvent is not particularly limited, but examples thereof include 2-pyrrolidone, 1-(2-hydroxyethyl)-2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, urea, lactam compounds, and the like.

[0037] The ink composition of this embodiment may contain urea. The inclusion of urea tends to improve the wettability of the ink composition and further improve clogging recovery. Note that urea provides the same effects as the organic solvents described above, and therefore is considered to be included in the organic solvents in this embodiment.

[0038] The content of urea is preferably 0.5 to 10% by mass, and more preferably 3.0 to 7.5% by mass, relative to the total amount of the ink composition. When the content of urea is within the above range, clogging recovery properties tend to be further improved.

[0039] The ink composition of this embodiment may contain a lactam compound. By including such a lactam compound, the lactam compound acts as a dissolution aid for the dye, improving the solubility of the dye. Furthermore, even when water evaporates, an increase in ink viscosity can be suitably suppressed, and clogging recovery tends to be further improved.

[0040] The lactam compound is not particularly limited, but examples thereof include ε-caprolactam, and it is preferable to use ε-caprolactam because the above-mentioned effects can be effectively obtained. Note that even lactam compounds that are solid at 25° C. can obtain the same effects as the organic solvents described above, and therefore in this embodiment, lactam compounds that are solid at 25° C. are also included in the organic solvent.

[0041] The content of the lactam compound is preferably 0.5 to 15% by mass, and more preferably 3.0 to 7.5% by mass, relative to the total amount of the ink composition. When the content of the lactam compound is within the above range, clogging recovery tends to be further improved.

[0042] The total content of organic solvents is 15.0% by mass or less, preferably 12.5% ​​by mass or less, or 10.0% by mass or less, relative to the total amount of the ink composition, and the total content of organic solvents is preferably 1.0% by mass or more, 2.5% by mass or more, 5.0% by mass or more, or 10.0% by mass or more, relative to the total amount of the ink composition. Although a total content of organic solvents of 15.0% by mass or less may result in a decrease in intermittent printing stability and clogging recovery, by using a recording head having a circulation flow path, it is possible to maintain good intermittent printing stability and clogging recovery even when the total content of organic solvents is low.

[0043] The content of high-boiling-point organic solvents having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less, preferably 2.5% by mass or less, 2.0% by mass or less, 1.5% by mass or less, 1.0% by mass or less, or even 0.5% by mass or less, relative to the total amount of the ink composition. The lower limit of the content of high-boiling-point organic solvents is not particularly limited, but may be 0% by mass or more. By reducing the content of high-boiling-point organic solvents to 3.0% by mass or less, drying properties tend to be improved and bleeding tends to be reduced. Furthermore, in this embodiment, by using a recording head having a circulation flow path, it is possible to improve intermittent printing stability and clogging recovery properties even if the content of high-boiling-point organic solvents, which generally improve intermittent printing stability and clogging recovery properties, is reduced to 3.0% by mass or less.

[0044] The organic solvent preferably contains a low-boiling organic solvent having a normal boiling point of 170.0° C. or more and less than 290.0° C. This shortens the drying time, reduces bleeding, and also reduces the environmental impact.

[0045] The content of the low-boiling organic solvent is preferably 1.0 to 15 mass %, 2.5 to 12.5 mass %, or 5.0 to 10 mass % relative to the total amount of the ink composition. When the content of the low-boiling organic solvent is within the above range, the drying time is shortened, bleeding is reduced, and the environmental load can also be reduced.

[0046] The organic solvent preferably contains one or both of an alkanediol having 5 or more carbon atoms and a glycol ether having 5 or more carbon atoms, which tends to further improve intermittent printing stability, clogging recovery, and drying properties.

[0047] The total amount of the alkanediols having 5 or more carbon atoms and the glycol ethers having 5 or more carbon atoms is preferably 1.0 to 14 mass%, 3.0 to 12 mass%, or 5.0 to 10 mass%, relative to the total amount of the ink composition. When the total amount of the alkanediols having 5 or more carbon atoms and the glycol ethers having 5 or more carbon atoms is within the above range, intermittent printing stability, clogging recovery, and drying properties tend to be further improved.

[0048] The circulation rate of the inkjet ink composition for textile printing per recording head is preferably 1.0 to 10 g / min, 1.0 to 7.0 g / min, 3.0 to 7.0 g / min, or 5.0 to 7.0 g / min. When the circulation rate is within the above range, intermittent printing stability and clogging recovery tend to be further improved.

[0049] The circulation flow path may have an example path that circulates the ink composition that has flowed out of a pressure chamber back to another pressure chamber, but it preferably has a path that causes the ink composition that has flowed out of a pressure chamber to flow back into the same pressure chamber.

[0050] The recording head is preferably a line head in which nozzles are arranged over a length equal to or greater than the recording width of the recording medium, and which performs recording on the recording medium in a single pass, which tends to further improve printing speed.

[0051] 1.4.Surfactants The ink composition may contain a surfactant. The surfactant is not particularly limited, but examples thereof include acetylene-based surfactants, silicone-based surfactants, and fluorine-based surfactants.

[0052] The acetylene glycol surfactant is not particularly limited, but examples thereof include alkylene oxide adducts of 2,4,7,9-tetramethyl-5-decyne-4,7-diol and 2,4,7,9-tetramethyl-5-decyne-4,7-diol, and alkylene oxide adducts of 2,4-dimethyl-5-decyne-4-ol and 2,4-dimethyl-5-decyne-4-ol.

[0053] The silicone surfactant is not particularly limited, but examples thereof include polysiloxane compounds and polyether-modified organosiloxanes.

[0054] The fluorine-based surfactant is not particularly limited, but examples thereof include perfluoroalkyl sulfonates, perfluoroalkyl carboxylates, perfluoroalkyl phosphates, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl betaines, and perfluoroalkyl amine oxide compounds.

[0055] The content of the surfactant is preferably 0.1 to 2.0 mass %, 0.2 to 1.5 mass %, or 0.3 to 1.0 mass %, relative to the total amount of the ink composition.

[0056] 1.5. pH adjuster The pH adjuster is not particularly limited, but examples thereof include inorganic acids (e.g., sulfuric acid, hydrochloric acid, nitric acid, etc.), inorganic bases (e.g., lithium hydroxide, sodium hydroxide, potassium hydroxide, ammonia, ammonium salts, etc.), organic bases (triethanolamine, diethanolamine, monoethanolamine, tripropanolamine, triisopropanolamine), and organic acids (e.g., adipic acid, citric acid, succinic acid, etc.).

[0057] In addition, among pH adjusters, those that are liquid at room temperature (25°C) are considered organic solvents for the purpose of calculating the content.

[0058] The content of the pH adjuster relative to the total amount of the ink composition is preferably 0.1 to 2.0 mass%, 0.2 to 1.5 mass%, or 0.3 to 2.0 mass%. When the content of the pH adjuster is within the above range, clogging recovery tends to be further improved.

[0059] 1.6.Water The water content is preferably 45 to 80 mass %, 50 to 75 mass %, or 55 to 70 mass %, relative to the total amount of the ink composition. When the water content is within the above range, intermittent printing stability, clogging recovery, and drying properties tend to be further improved.

[0060] 2. Recording Headset The recording headset of this embodiment is a recording headset comprising the ink jet ink composition for textile printing and the recording head described above. Details of the ink jet ink composition for textile printing and the recording head are as described above.

[0061] In the recording head set, the recording head is preferably a line head in which nozzles are arranged over a length equal to or greater than the recording width of the recording medium, and which performs recording on the recording medium in one pass.

[0062] 3. Inkjet recording method The inkjet recording method of this embodiment includes a deposition step of ejecting the inkjet ink composition for textile printing from the recording head and depositing it on a recording medium. Details of the inkjet ink composition for textile printing and the recording head are as described above.

[0063] 3.1.Attachment process The deposition step is a step of ejecting the ink composition from the recording head and depositing it on the recording medium. More specifically, the pressure generating means of the pressure chamber 2 is driven to eject the ink composition filled in the recording head 131 from the nozzle 1. This ejection method is also called an inkjet method, and the recording head is also called an inkjet head.

[0064] The recording head is preferably a line head in which nozzles are arranged over a length equal to or greater than the recording width of the recording medium, and the deposition step is preferably performed in one pass over the recording medium.

[0065] It is also preferable that the attachment step be carried out while transporting the recording medium at a transport speed of 30.0 m / min or more.

[0066] 3.2.First heating step The inkjet method of this embodiment may include a first heating step of heating the composition in the recording head. More specifically, the method may include a heating step of heating the composition in a circulation flow path composed of a pressure chamber 2, a circulation flow path 3, and a connecting path 4. The heating means is not particularly limited and may be provided, for example, in the pressure chamber 2, the circulation flow path 3, or the connecting path 4. Additionally, a heating means for heating the nozzle plate may be provided, or, if the circulation flow path 3 passes through an area outside the recording head 131, a heating means may be provided in the circulation flow path 3 located outside the recording head 131. Furthermore, a heating means may be provided in an ink flow path upstream of the pressure chamber. Here, the ink flow path refers to a flow path for distributing ink. The ink flow path also includes, for example, an ink supply path for supplying ink from an ink storage container that stores ink to an inkjet recording head.

[0067] The heating temperature of the ink composition in the heating step is preferably 25 to 60° C., and more preferably 30 to 40° C. By combining such a heating step with a recording head that circulates the ink composition, it is possible to further improve the intermittent printing stability and clogging recovery properties of the ink composition.

[0068] 3.3.Second heating process The inkjet method of this embodiment may further include a second heating step of heating the recording medium to which the ink composition has been attached after the ejection step. Heating can evaporate the water and solvent in the attached ink composition, which tends to further improve the drying properties.

[0069] 3.4.Fixing process In the inkjet method of this embodiment, in order to fix the dye adhered to the recording medium, a fixing step (steaming step) may be performed after the above steps by exposing the recording medium to water vapor in a high-temperature environment. The preferred temperature range varies slightly depending on the type of fabric and dye used, but a temperature range of approximately 100 to 110°C is preferred. The exposure time is preferably 10 to 20 minutes for cellulosic fibers such as cotton and viscose rayon, and approximately 20 to 40 minutes for amide fibers such as silk, wool, and nylon. By performing the fixing process within these ranges, the dye can be well fixed to the fiber.

[0070] 3.5. Cleaning process In the inkjet method of this embodiment, after the fixing step, it is preferable to wash the recording medium and then dry it. The specific flow is water washing (at room temperature), hot water washing, soaping, and drying, but either water washing or hot water washing can be done alone. The purpose of water washing, hot water washing, and soaping is to thoroughly wash away any unfixed dye, and it is desirable to carry out each step for several minutes or more. The temperature of the water used for hot water washing is preferably 40 to 60°C.

[0071] Soaping refers to the process of stirring the dye in a hot water bath with cleaning aids. The water temperature should be 40-70°C when using acid dyes or direct dyes, and 80-100°C when using reactive dyes. Commercially available cleaning aids can be used.

[0072] Regarding drying, any method can be used as long as it does not damage the state of the recording medium, such as hot air drying, in which hot air is blown onto or exposed to the recording medium, or press drying, in which heat is applied using an iron or a hot press.

[0073] 2.6. Recording Media The recording medium is not particularly limited, but may be, for example, a fabric. The fabric is not particularly limited, but examples thereof include natural fibers such as silk, cotton, wool, nylon, and rayon, or synthetic fibers.

[0074] 4. Inkjet recording device The inkjet recording apparatus of this embodiment is an inkjet recording apparatus equipped with an inkjet ink composition for textile printing containing a water-soluble dye and an organic solvent, and a recording head. The details of the inkjet ink composition for textile printing and the recording head are as described above. [Example]

[0075] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited to the following examples.

[0076] 1. Preparation of Inkjet Composition 3A to 3C and 4A to 4C, the components were placed in a stainless steel container, a mixing tank, and mixed and stirred until completely dissolved. After that, the mixture was further mixed and stirred at room temperature for 1 hour, and then filtered through a 5 μm membrane filter to obtain the textile printing ink composition of each example. Note that the numerical values ​​of each component shown in each example in the figures represent mass % unless otherwise specified.

[0077] <Water-soluble dye> Reactive Black 39 Reactive Black 5 Reactive Yellow 95 Reactive Red 31 Reactive Red 24:1 Reactive Blue 49 Reactive Orange 13 Reactive Yellow 15 Reactive Red 123 Reactive Blue 222 Acid Black 172 Acid Red 249 Acid Yellow 79 Acid Blue 140 Direct Blue 199 ·Acid Orange 33 ·Direct Orange 26 ·Acid Red 138 ·Acid Violet 54 ·Acid Orange 116 ·Acid Blue 290 ·Acid Blue 113 <Water-soluble organic solvent> ·Propylene glycol ·1,3-Butanediol ·1,2-Hexanediol ·2-Methyl-1,3-propanediol ·Diethylene glycol monobutyl ether ·Diethylene glycol ·2-Pyrrolidone ·3-Methyl 1,5-pentanediol ·Triethylene glycol monobutyl ether ·Triethylene glycol ·Glycerin<000,0356>·2-Hydroxyethyl pyrrolidone ·Urea ·ε-Caprolactam <pH adjuster><000036,0>·Triisopropanolamine (TPA) ·Triethanolamine (TEA) ·Adipic acid ·Citric acid <Surfactant> ·Surfynol 465 (Nissin Chemical Industry Co., Ltd., acetylene glycol-based surfactant) ·Surfynol 104H (Nissin Chemical Industry Co., Ltd., acetylene glycol-based surfactant) [[ID=6,1]]

[0078] 2. Evaluation method<00,.,370>2.1. Evaluation of clogging recovery A Monna-Lisa EVO T16 180 (manufactured by Robustelli) was prepared as the inkjet recording apparatus 2. In addition, a recording apparatus was prepared as the inkjet recording apparatus 1 by modifying the inkjet recording apparatus 2 (Monna-Lisa EVO T16 180 (manufactured by Robustelli)) so as to include a liquid ejecting head having a circulation flow path as shown in FIG.

[0079] Using each of the inkjet recording apparatuses 1 and 2, the textile printing ink composition was continuously ejected from the liquid ejection head for 10 minutes under conditions of 23°C and 50% RH, and then the ink composition was left as is for 1 hour without capping or the like.

[0080] After leaving it, the textile ink composition was ejected onto photo paper until it was ejected normally from all nozzles. At this time, the number of ink droplets until normal ejection was achieved was counted. Based on the count of ink droplets, the clogging recovery ability was evaluated according to the following evaluation criteria. Note that the drive voltage of the PZT element was adjusted so that the amount of textile ink composition ejected in each inkjet recording device 1 and inkjet recording device 2 was the same. Note that there are no practical problems up to a rating of C. (Evaluation criteria) S: Normalizes under 500 shots A: Normalized between 500 and 2000 shots B: Normalized between 2000 and 5000 shots C: Normalized between 5,000 and 10,000 shots D: Not normalized after 10,000 shots, normalized after nozzle cleaning E: Not normalized after 10,000 shots, and some nozzles do not return to normal even after nozzle cleaning F: 10,000 shots did not return to normal, and even after nozzle cleaning, most nozzles did not eject.

[0081] The inkjet recording apparatus 1 was evaluated by changing the circulation speed.

[0082] 2.2. Evaluation of print density Using the inkjet recording apparatus 1, the ink composition shown in FIGS. 3D and 4D was applied to the fabric in an amount of 19.3 g / m 2 The fabric used was a silk fabric (14 momme silk habutae, manufactured by Shikizome Co., Ltd.) that had been treated with a pretreatment solution containing 1.0% by mass of sodium alginate, 1.0% by mass of guar gum, 4.0% by mass of ammonium sulfate, 10.0% by mass of urea, and the balance of water, and then squeezed and dried using a mangle at a pickup rate of 20%.

[0083] After solid printing, the fabric was steamed at 102°C for 30 minutes using a steamer (Matisse; Steamer DHe type), then washed with water to remove unfixed dye. After further washing with hot water (40°C for 10 minutes), the fabric was washed for 10 minutes using hot water at 55°C containing 0.2% by mass of Laccol STA (cleaning aid; Meisei Chemical Industry Co., Ltd.), rinsed with water at room temperature, and dried to produce a printed fabric.

[0084] The density (OD value) of the printed fabric obtained as described above was measured using a spectrodensitometer FD-7 (Konica Minolta). In the measurement, a polarizing filter was used to match the color of each colorant, and the color region (Dk, Dc, Dm, Dy) suitable for each colorant was determined. The measurement conditions were: light source: D65, viewing angle: 10 degrees, Status-T, with UV filter.

[0085] 2.3. Evaluation of drying properties A serial inkjet recording apparatus 1 and an inkjet recording apparatus 3, which is a one-pass experimental apparatus having a circulation head, were prepared.

[0086] Using the ink compositions of the comparative examples, the application amount was adjusted so that the amount of dye adhered per unit area was the same as that of the ink compositions of the examples, and solid printing was performed using the inkjet recording apparatus 1 to prepare printed fabrics. Specifically, A2 had a dye content ratio of 1 / 4 that of the ink of A1, so it was 19.3 mg / m 2The ink was applied in the same amount and four times to the same location, but otherwise the same procedure was followed as for the production of the printed fabric described above. The same procedure was followed for other inks depending on the dye content.

[0087] In addition, using the ink compositions of the comparative examples, the amount of dye applied per pass was adjusted so that the amount of dye attached per unit area was the same as that of the ink compositions of the examples, and solid printing was performed using the inkjet recording device 3 to prepare printed fabrics. Specifically, A2 has a dye content ratio of 1 / 4 that of the ink of A1, so it was 77.2 mg / m 2 (4 × 19.3 mg / m 2 The ink was discharged at an application amount of 1000 ppm, and the other steps were the same as those for producing the printed fabric described above. The same procedure was followed for other inks depending on the dye content ratio.

[0088] The printed fabric obtained as described above was dried at a heater temperature of 100°C.

[0089] The print density of each of the obtained printed fabrics was measured, and the degree of bleeding at the edges of the solid print was judged by visual observation. Based on the results, the prints were evaluated according to the following criteria. (Evaluation criteria) A: There is no bleeding at the edges and the outline is very sharp and clear. B: There is some blurring, but the outline is discernible. C: The colors are blurred and the outline is unclear. D: There is so much blurring that it is impossible to tell where the outline is.

[0090] 2.4. Evaluation of washing fastness The printed fabrics obtained as described above were subjected to fastness tests in accordance with the standards for washing fastness (JIS L 0844:2011 A-2), sweat fastness (JIS L 848:2004), and water fastness (JIS L 846:2004). The attached white cloth used in the tests was silk (No. 2-1) as specified in JIS L 0803 for inks A1-X1, A2, B2, F2, and M2. The attached white cloth used in the tests was cotton (No. 3-1) as specified in JIS L 0803 for inks A3-U3, A4, B4, F4, and O4. The attached white cloth was purchased from the Japanese Standards Association. The numbers in the figure indicate the grade of each fastness test result. [Explanation of symbols]

[0091] 1... nozzle, 2... pressure chamber, 3... circulation flow path, 4... communication path, 100... inkjet recording device, 110... feeding section, 120... conveying section, 130... recording section, 131... recording head, 140... drying section, 141... drying section, 142... drying section, 150... discharge section

Claims

1. An inkjet ink composition for textile printing that is ejected from a recording head by an inkjet method, Contains a water-soluble dye and an organic solvent, the total content of the organic solvents is 15.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of a high-boiling organic solvent having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, the recording head has a nozzle for ejecting the inkjet ink composition for textile printing, a pressure chamber for applying pressure to the inkjet ink composition for textile printing, and a circulation flow path for circulating the inkjet ink composition for textile printing supplied to the recording head within the recording head; Inkjet ink composition for textile printing.

2. The organic solvent contains a low-boiling organic solvent having a normal boiling point of 170.0°C or higher and lower than 290.0°C. The inkjet ink composition for textile printing according to claim 1 .

3. The organic solvent contains one or both of an alkanediol having 5 or more carbon atoms and a glycol ether having 5 or more carbon atoms. The inkjet ink composition for textile printing according to claim 1 .

4. the circulation amount of the inkjet ink composition for textile printing is 1.0 to 7.0 g / min per recording head; The inkjet ink composition for textile printing according to claim 1 .

5. the circulation flow path has a path through which the inkjet ink composition for textile printing that has flowed out of the pressure chamber flows back into the pressure chamber; The inkjet ink composition for textile printing according to claim 1 .

6. the recording head is a line head in which nozzles are arranged over a length equal to or greater than the recording width of the recording medium, and performs recording on the recording medium in one pass; The inkjet ink composition for textile printing according to claim 1 .

7. The water-soluble dye contains two or more dyes. The inkjet ink composition for textile printing according to claim 1 .

8. the total content of the water-soluble dyes is more than 25% by mass relative to the total amount of the inkjet ink composition for textile printing; The inkjet ink composition for textile printing according to claim 1 .

9. A recording headset comprising an inkjet ink composition for textile printing and a recording head, the inkjet ink composition for textile printing contains a water-soluble dye and an organic solvent, the total content of the organic solvents is 15.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of a high-boiling organic solvent having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, the recording head has a nozzle for ejecting the inkjet ink composition for textile printing, a pressure chamber for applying pressure to the inkjet ink composition for textile printing, and a circulation flow path for circulating the inkjet ink composition for textile printing supplied to the recording head within the recording head; Recording headset.

10. the recording head is a line head in which nozzles are arranged over a length equal to or greater than the recording width of the recording medium, and performs recording on the recording medium in one pass; 10. The recording headset of claim 9.

11. a deposition step of ejecting the inkjet ink composition for textile printing from a recording head and depositing it on a recording medium, The inkjet ink composition for textile printing contains a water-soluble dye and an organic solvent, the total content of the organic solvents is 15.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of a high-boiling organic solvent having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, the recording head has a nozzle for ejecting the inkjet ink composition for textile printing, a pressure chamber for applying pressure to the inkjet ink composition for textile printing, and a circulation flow path for circulating the inkjet ink composition for textile printing supplied to the recording head within the recording head; Inkjet recording method.

12. the recording head is a line head in which nozzles are arranged over a length equal to or greater than the recording width of the recording medium, and the deposition step is performed on the recording medium in one pass; The inkjet recording method according to claim 11.

13. The adhering step is carried out by conveying the recording medium at a conveying speed of 30.0 m / min or more. The inkjet recording method according to claim 11.

14. An inkjet recording apparatus comprising: an inkjet ink composition for textile printing containing a water-soluble dye and an organic solvent; and a recording head, 15.0% by mass or less of the total amount of the ink composition; the content of a high-boiling organic solvent having a normal boiling point of 290.0°C or higher among the organic solvents is 3.0% by mass or less relative to the total amount of the inkjet ink composition for textile printing, the content of the water-soluble dye is 5.0% by mass or more relative to the total amount of the inkjet ink composition for textile printing, the recording head has a nozzle for ejecting the inkjet ink composition for textile printing, a pressure chamber for applying pressure to the inkjet ink composition for textile printing, and a circulation flow path for circulating the inkjet ink composition for textile printing supplied to the recording head within the recording head; Inkjet recording device.

Images