Printer and method for producing printed matter

Abstract

To provide a printer that makes it possible to produce a printed matter capable of partly erasing among a printed image, without using an additional ink and a method for producing a printed matter.SOLUTION: A control unit controls the pretreatment liquid ejection head 31 to discharge pretreatment liquid onto the fabric, and controls the white ink ejection head 32 and color ink ejection head 33 to discharge ink onto the fabric where the pretreatment liquid has been applied to print the main image and additional image. The control unit prints the main image by adjusting the weight ratio of the pretreatment liquid to the ink so that the wash fastness of the area of the fabric where the main image is printed reaches a predetermined first level or higher, and prints the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the wash fastness of the area of the fabric where the additional image is printed is a predetermined second level or lower, which is lower than the first level, thereby controlling the pretreatment liquid ejection head 31, the white ink ejection head 32, and the color ink ejection head 33.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a printing apparatus and a method for producing a printed item. [Background technology]

[0002] There is a known technique for producing a printed item by printing an image such as letters, pictures, or designs onto fabric such as clothing, etc. However, there is a demand for erasing only a portion of the image on the printed item.

[0003] For example, if an image including an advertising image that is required for a relatively short period of time from the day of the event is printed on a T-shirt or the like to be used as an event merchandise, it may be desired to erase the advertising image after the required period has passed and leave the other images.

[0004] In this regard, Patent Document 1 discloses a technology in which a colored portion is formed by printing at least two types of ink, one with high washing fastness and the other with low washing fastness, and the colored portion formed with the ink with low washing fastness discolors, fades, loses color or loses color upon washing, while the colored portion formed with the ink with high washing fastness is visible.

[0005] Using this technology, it is possible to wash a cloth printed with an image to be erased and an image to be kept, so that the image to be erased disappears and the image not to be erased remains. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 7130292 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the technology of Patent Document 1 requires multiple types of ink with different washing fastnesses, which means that additional inks must be used to print different images that need to be erased and images that do not.

[0008] The present invention has been made in consideration of the above, and aims to provide a printing device and a method for producing printed textiles that enable the production of printed textiles in which only part of the printed image can be erased without using additional ink. [Means for solving the problem]

[0009] According to one aspect of the present invention, there is provided a printing device comprising: a pretreatment liquid ejection unit that ejects a pretreatment liquid that aggregates ink; an ink ejection unit that ejects ink; and a control unit that controls the pretreatment liquid ejection unit to eject the pretreatment liquid onto a cloth and the ink ejection unit to eject ink onto the cloth onto which the pretreatment liquid has been ejected, thereby printing a main image and an additional image, wherein the control unit controls the pretreatment liquid ejection unit and the ink ejection unit to print the main image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area of ​​the cloth where the main image is printed is equal to or higher than a predetermined first level, and to print the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area of ​​the cloth where the additional image is printed is equal to or lower than a predetermined second level that is lower than the first level.

[0010] According to another aspect of the present invention, there is provided a method for producing a textile print, comprising the steps of discharging a pretreatment liquid that aggregates ink onto a cloth, and discharging ink onto the cloth onto which the pretreatment liquid has been discharged to print a main image, and discharging the pretreatment liquid onto the cloth and discharging ink onto the cloth onto which the pretreatment liquid has been discharged to print an additional image, wherein in the step of printing the main image, the weight ratio of the pretreatment liquid to the ink is adjusted so that the washing fastness of the area of ​​the cloth where the main image is printed is equal to or higher than a predetermined first level, and in the step of printing the additional image, the weight ratio of the pretreatment liquid to the ink is adjusted so that the washing fastness of the area of ​​the cloth where the additional image is printed is equal to or lower than a second level that is lower than the first level. [Effects of the Invention]

[0011] According to the present invention, it is possible to produce a printed item in which only a part of a printed image can be erased without using additional ink. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram showing a schematic configuration of a printing system according to an embodiment. [Figure 2] 2 is a schematic configuration diagram of a printing unit of the printing device of the printing system shown in FIG. 1. [Figure 3] 2 is a flowchart illustrating the operation of the printing system shown in FIG. [Figure 4] FIG. 10 is a diagram illustrating an example of an application screen. [Figure 5] FIG. 1 shows an example of unwashed fabric printed with a main image and an additional image. [Figure 6] FIG. 6 is a diagram showing the state in which the additional image has disappeared after washing the cloth shown in FIG. 5. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts and components are designated by the same or equivalent reference numerals throughout the drawings.

[0014] The following embodiments are examples of devices that embody the technical idea of ​​the present invention, and the technical idea of ​​the present invention does not limit the materials, shapes, structures, arrangements, etc. of each component to those described below. The technical idea of ​​the present invention can be modified in various ways within the scope of the claims.

[0015] Fig. 1 is a block diagram showing a schematic configuration of a printing system provided with a printing device according to an embodiment of the present invention. Fig. 2 is a schematic configuration diagram of a printing unit of the printing device of the printing system shown in Fig. 1. In Fig. 2, the direction perpendicular to the paper surface is the up-down direction, and the front side of the paper surface is the up direction. In Fig. 2, the front-rear and left-right directions are the front-rear and left-right directions.

[0016] 1, a printing system 1 according to this embodiment includes a printing device 2, a terminal device 3, and a drying device 4. The printing device 2 and the terminal device 3 are capable of communicating with each other via a network 5 such as a LAN.

[0017] The printing device 2 prints on fabric, which is a printing medium. The printing device 2 is a so-called garment printer that uses clothing such as a T-shirt as a printing medium.

[0018] Examples of fabrics include natural fibers such as cotton, silk, wool, and linen; chemical fibers such as polyester, acrylic, polyurethane, nylon, rayon, cupra, and acetate; and blends of these fibers. The fabric may be woven, knitted, or nonwoven.

[0019] The printing device 2 includes a printing unit 11, a transport unit 12, a communication unit 13, and a control unit .

[0020] The printing unit 11 performs printing on the fabric by inkjet printing. The printing unit 11 includes a head unit 21 and a rail unit 22.

[0021] The head unit 21 performs printing by ejecting a pretreatment liquid and inks (white ink and color inks) onto a fabric. As shown in Fig. 2, the head unit 21 includes a pretreatment liquid ejection head 31, a white ink ejection head 32, a plurality of color ink ejection heads 33, and a head holder 34.

[0022] The pretreatment liquid ejection head 31, the white ink ejection head 32, and the color ink ejection head 33 correspond to ink ejection units. The pretreatment liquid ejection head 31 corresponds to the pretreatment liquid ejection unit, the white ink ejection head 32 corresponds to the white ink ejection unit, and the color ink ejection head 33 corresponds to the color ink ejection unit.

[0023] The pretreatment liquid ejection head 31 ejects the pretreatment liquid. The pretreatment liquid ejection head 31 has a plurality of nozzles (not shown) that open on its lower surface (ejection surface) and are arranged along the front-rear direction (sub-scanning direction), and ejects the pretreatment liquid from the nozzles. The pretreatment liquid will be described in detail later.

[0024] The white ink ejection head 32 ejects white ink. The white ink ejection head 32 has the same configuration as the pretreatment liquid ejection head 31, except for the liquid that is ejected. The white ink ejection head 32 is disposed behind the pretreatment liquid ejection head 31 in the front-rear direction (sub-scanning direction). Details of the white ink will be described later.

[0025] The color ink ejection heads 33 eject color inks. In this embodiment, four color ink ejection heads 33 are provided, each ejecting black, cyan, magenta, and yellow ink. The color ink ejection heads 33 have the same configuration as the pretreatment liquid ejection head 31, except that the liquids they eject are different. The four color ink ejection heads 33 are arranged behind the white ink ejection head 32 in the front-to-rear direction (sub-scanning direction). The four color ink ejection heads 33 are arranged side by side in the left-to-right direction (main scanning direction). Details of the color inks will be described later.

[0026] The head holder 34 holds the pretreatment liquid ejection head 31 , the white ink ejection head 32 , and the four color ink ejection heads 33 .

[0027] The rail portion 22 moves the head unit 21 back and forth in the left and right direction (main scanning direction).

[0028] The transport unit 12 has a support unit (not shown) that supports the fabric, and transports the fabric supported by the support unit below the head unit 21 in a transport direction (sub-scanning direction) from the front side to the rear side.

[0029] The communication unit 13 performs communication processing with the terminal device 3 via the network 5 .

[0030] The control unit 14 controls the overall operation of the printing device 2. The control unit 14 is configured with a CPU, RAM, ROM, a hard disk, and the like.

[0031] Specifically, the control unit 14 controls the pretreatment liquid ejection head 31 to eject the pretreatment liquid onto the cloth, the white ink ejection head 32 to eject the white ink onto the cloth onto which the pretreatment liquid has been ejected, and the color ink ejection head 33 to eject the color ink onto the cloth onto which the pretreatment liquid and the white ink have been ejected, thereby printing an image.

[0032] In this embodiment, an image including a main image, which is an image of the main pattern or the like to be formed on the fabric, and an additional image, which is an image required in the short term, may be printed on a single piece of fabric. The main image is printed as an image that will not disappear even when the fabric is washed, and the additional image is printed as an image that will disappear when the fabric is washed. For example, an additional image may be an advertising image that is desired to be displayed on the clothing for a short period of time when printing on clothing such as a T-shirt.

[0033] When printing an image including a main image and an additional image, the control unit 14 controls the pretreatment liquid ejection head 31, the white ink ejection head 32, and the color ink ejection head 33 to print the main image by adjusting the weight ratio of the pretreatment liquid to the ink (white ink and color ink) so that the washing fastness of the area where the main image of the cloth is printed is a predetermined first level or higher, and to print the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area where the additional image of the cloth is printed is a predetermined second level or lower that is lower than the first level.

[0034] The first level indicates the lower limit of washing fastness at which the image will not fade even when the fabric is washed. For example, the first level can be grade 3 or higher in terms of washing fastness in accordance with JIS L 0844 A-2.

[0035] The second level indicates the upper limit of washing fastness at which the image disappears when the fabric is washed. For example, the second level can be Grade 1 in terms of washing fastness according to JIS L 0844 A-2.

[0036] The wash fastness of the image printed on the fabric depends mainly on the weight ratio of the pretreatment liquid to the ink. Specifically, the greater the weight ratio of the pretreatment liquid to the ink, the lower the wash fastness.

[0037] The higher the weight ratio of pretreatment liquid to ink, the closer the ink film is formed to the surface of the fabric. This makes the ink film more susceptible to damage during washing. Furthermore, since relatively little of the ink film becomes entangled with the fabric fibers, the ink film is more likely to peel off from the fabric. Therefore, the higher the weight ratio of pretreatment liquid to ink, the lower the wash fastness.

[0038] Furthermore, when a pretreatment liquid containing a metal salt is used and a relatively large amount of the metal salt is present in the ink coating, the metal salt dissolves during washing, creating voids in the ink coating. These voids cause cracks in the ink coating, making it more likely to detach from the fabric. Therefore, the greater the weight ratio of the pretreatment liquid to the ink, the lower the washfastness.

[0039] The weight ratio of the pretreatment liquid to the ink used to print the main image is preferably 0.4 or less to ensure washing fastness such that the main image will not fade even when the fabric is washed, and the weight ratio of the pretreatment liquid to the ink used to print the additional image is preferably 0.55 or more to ensure washing fastness such that the additional image will not fade when the fabric is washed.

[0040] The terminal device 3 transmits print data to the printing device 2. The terminal device 3 is configured by a computer equipped with a CPU, ROM, RAM, a hard disk, a display unit configured with a liquid crystal display panel, etc., and an input unit having a keyboard, mouse, etc. (none of which are shown).

[0041] The drying device 4 dries the cloth printed by the printing device 2. As the drying device 4, for example, a heat press, a roll heater, a hot air device, an infrared lamp heater, or the like can be used.

[0042] Next, the pretreatment liquid will be described.

[0043] The pretreatment liquid is a liquid that aggregates the ink, and preferably contains an aggregating agent and water.

[0044] The flocculant may be a component that has the effect of flocculating the coloring material in the ink on the fabric, which is the printing medium. When ink is further applied to the fabric to which the pretreatment liquid has been applied, the coloring material in the ink will flocculate on the fabric, thereby increasing the image density and preventing image bleeding. Specific examples of the flocculant include metal salts, cationic polymers, organic acids, and the like, or combinations of these.

[0045] The content of the ink aggregating agent in the pretreatment liquid is adjusted appropriately depending on the type of ink aggregating agent, the composition of the ink to be applied to the fabric after the pretreatment liquid has been applied, and other factors, but may be, for example, 5% by mass or more, 10% by mass or more, or 15% by mass or more. It may also be 50% by mass or less, 45% by mass or less, or 40% by mass or less. The content of the ink aggregating agent in the pretreatment liquid may be, for example, in the range of 5 to 50% by mass.

[0046] As the metal salt, a polyvalent metal salt can be preferably used. The use of a polyvalent metal salt makes it easy to adjust the washing fastness by changing the amount of the pretreatment liquid dispensed, and makes it easy to print the main image as an image that does not fade even when the fabric is washed, and the additional image as an image that fades when the fabric is washed.

[0047] Polyvalent metal salts are composed of divalent or higher polyvalent metal ions and anions. Examples of divalent or higher polyvalent metal ions include Ca. 2+ , Mg 2+ , Cu 2+ , Ni 2+ , Zn 2+ , Ba 2+ Examples of anions include Cl - , NO 3- , CH3COO - , I - , Br - , ClO3 - Specific examples of polyvalent metal salts include calcium chloride, calcium nitrate, magnesium nitrate, copper nitrate, calcium acetate, and magnesium acetate.

[0048] As the cationic polymer, a cationic water-soluble resin can be preferably used. Examples of the cationic water-soluble resin include polyethyleneimine (PEI), polyvinylamine, polyallylamine and its salts, polyvinylpyridine, and cationic acrylamide copolymers. More specifically, for example, polydiallyldimethylammonium chloride can be used.

[0049] Examples of organic acids include formic acid, acetic acid, oxalic acid, malic acid, citric acid, and ascorbic acid.

[0050] The pretreatment liquid preferably contains water, but may contain a water-soluble organic solvent in addition to or instead of water.

[0051] The water is not particularly limited, but examples thereof include ion-exchanged water, distilled water, and ultrapure water.

[0052] The amount of water is preferably 30 to 90 mass %, more preferably 40 to 85 mass %, and even more preferably 50 to 80 mass %, based on the total amount of the pretreatment liquid.

[0053] As the water-soluble organic solvent, an organic compound that is liquid at room temperature (25°C) and dissolves in water can be used, and it is preferable to use a water-soluble organic solvent that is uniformly miscible with the same volume of water at 20°C under 1 atmosphere. For example, lower alcohols such as methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, 1,3-propanediol, 1,3-butanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, and 2-methyl-2-propanol; Glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, and polypropylene glycol; Glycerols such as glycerin, diglycerin, triglycerin, and polyglycerin; acetins such as monoacetin and diacetin; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol dimethyl ether, and tetraethylene glycol diethyl ether; Examples of usable solvents include β-thiodiglycol and sulfolane. The boiling point of the water-soluble organic solvent is preferably 100°C or higher, and more preferably 150°C or higher.

[0054] These water-soluble organic solvents may be used alone or in combination of two or more. When two or more water-soluble organic solvents are contained, the total content of the water-soluble organic solvents is preferably 10 to 50 mass %, more preferably 15 to 40 mass %, and even more preferably 15 to 30 mass %, based on the total amount of the pretreatment liquid.

[0055] The pretreatment liquid may further contain a surfactant. The surfactant may be an anionic surfactant, a cationic surfactant, an amphoteric surfactant, or a nonionic surfactant, with a nonionic surfactant being more preferred. Furthermore, either a low-molecular-weight surfactant or a high-molecular-weight surfactant may be used.

[0056] The HLB value of the surfactant is preferably 5-20, and more preferably 10-18.

[0057] Examples of nonionic surfactants include ester surfactants such as glycerin fatty acid esters and fatty acid sorbitan esters; ether surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers and polyoxypropylene alkyl ethers; ether ester surfactants such as polyoxyethylene sorbitan fatty acid esters; acetylene surfactants; silicone surfactants; fluorine surfactants; etc. Among these, acetylene surfactants such as acetylene glycol surfactants are preferably used.

[0058] Examples of the acetylene surfactant include an acetylene glycol surfactant, an acetylene alcohol surfactant, and a surfactant having an acetylene group.

[0059] The acetylene glycol surfactant is a glycol having an acetylene group, preferably a glycol having a symmetrical structure with the acetylene group located in the center, and may have a structure in which ethylene oxide is added to acetylene glycol.

[0060] Commercially available acetylene surfactants include, for example, the Surfynol series manufactured by Evonik Industries, such as "Surfynol 104E," "Surfynol 104H," "Surfynol 420," "Surfynol 440," "Surfynol 465," and "Surfynol 485," and the Olfin series manufactured by Nissin Chemical Industry Co., Ltd., such as "Olfin E1004," "Olfin E1010," and "Olfin E1020" (all trade names).

[0061] Examples of silicone surfactants include polyether-modified silicone surfactants, alkyl-aralkyl-co-modified silicone surfactants, and acrylic silicone surfactants.

[0062] Examples of commercially available silicone surfactants include "Silface SAG002" and "Silface 503A" manufactured by Nissin Chemical Industry Co., Ltd. (both are trade names).

[0063] Other nonionic surfactants include polyoxyethylene alkyl ether surfactants such as those in the Emulgen series manufactured by Kao Corporation, including "Emulgen 102KG," "Emulgen 103," "Emulgen 104P," "Emulgen 105," "Emulgen 106," "Emulgen 108," "Emulgen 120," "Emulgen 147," "Emulgen 150," "Emulgen 220," "Emulgen 350," "Emulgen 404," "Emulgen 420," "Emulgen 705," "Emulgen 707," "Emulgen 709," "Emulgen 1108," "Emulgen 4085," and "Emulgen 2025G" (all trade names).

[0064] Examples of anionic surfactants include the Emeral series, manufactured by Kao Corporation, such as "Emeral 0," "Emeral 10," "Emeral 2F," "Emeral 40," and "Emeral 20C," the Neopelex series, such as "Neopelex GS," "Neopelex G-15," "Neopelex G-25," and "Neopelex G-65," the Pelex series, such as "Pelex OT-P," "Pelex TR," "Pelex CS," "Pelex TA," "Pelex SS-L," and "Pelex SS-H," and the Demol series, such as "Demol N," "Demol NL," "Demol RN," and "Demol MS" (all of which are trade names).

[0065] Examples of cationic surfactants include the Acetamine series (manufactured by Kao Corporation) such as "Acetamine 24" and "Acetamine 86," the Cortamine series (manufactured by Kao Corporation) such as "Cortamine 24P," "Cortamine 86P," "Cortamine 60W," and "Cortamine 86W," and the Sanisol series (manufactured by Kao Corporation) such as "Sanisol C" and "Sanisol B-50" (all trade names).

[0066] Examples of amphoteric surfactants include the Amphitol series manufactured by Kao Corporation, such as Amphitol 20BS, Amphitol 24B, Amphitol 86B, Amphitol 20YB, and Amphitol 20N (all trade names).

[0067] The surfactants may be used alone or in combination of two or more.

[0068] The amount of the surfactant, in terms of active ingredient, is preferably 0.1 to 10 mass %, more preferably 0.2 to 5 mass %, relative to the total amount of the pretreatment liquid. When two or more surfactants are used, the above content of the surfactants refers to the total content thereof.

[0069] The pretreatment liquid may further contain other components, such as a pH adjuster, a preservative, a rust inhibitor, and an antifoaming agent.

[0070] The method for producing the pretreatment liquid is not particularly limited, and the pretreatment liquid can be produced by any known method. For example, the pretreatment liquid can be obtained by dispersing all of the components in a mixer such as a Three-One Motor, either all at once or in portions, and then passing the mixture through a filter such as a membrane filter, if desired.

[0071] Next, the above-mentioned white ink will be described.

[0072] The white ink is ejected onto the fabric to conceal the color of the fabric, which is the printing medium, and make the printed image more visible, even if the fabric is a dark color such as black.

[0073] The white ink can contain a white pigment as a coloring material. By containing the white pigment, the white ink can be used to form an image that exhibits white color. The white pigment may be either an inorganic pigment or an organic pigment, or a combination of these may be used.

[0074] Examples of white pigments include white inorganic pigments such as titanium oxide, zinc oxide, zinc sulfide, antimony oxide, and zirconium oxide. Furthermore, white organic pigments such as hollow resin microparticles and solid resin microparticles can also be used. Among these, titanium oxide pigments are preferred from the viewpoint of opacity. The average particle diameter of the white pigment is preferably 50 nm or more, 100 nm or more, or 200 nm or more from the viewpoint of opacity, and preferably 500 nm or less, 400 nm or less, or 300 nm or less from the viewpoint of discharge stability. The average particle diameter of titanium oxide pigments is more preferably 200 to 300 nm from the viewpoints of opacity and discharge stability. When using titanium oxide pigments, it is preferable to use those that have been surface-treated with alumina, silica, or the like to suppress photocatalytic activity. The amount of surface treatment is preferably 5 to 20% by mass of the pigment.

[0075] A self-dispersing pigment may be used as the white pigment. A self-dispersing pigment is a pigment in which a hydrophilic functional group has been introduced onto the pigment surface by chemical or physical treatment. The hydrophilic functional group introduced into the self-dispersing pigment is preferably ionic, and by charging the pigment surface anionically or cationic, the pigment particles can be stably dispersed in water due to electrostatic repulsion. Preferred anionic functional groups include carboxyl groups, sulfo groups, and phosphate groups. Preferred cationic functional groups include quaternary ammonium groups and quaternary phosphonium groups.

[0076] These hydrophilic functional groups may be bonded directly to the pigment surface or via other atomic groups. Examples of such other atomic groups include, but are not limited to, alkylene groups, phenylene groups, and naphthylene groups. Examples of methods for treating the pigment surface include diazotization, sulfonation, hypochlorous acid treatment, humic acid treatment, and vacuum plasma treatment.

[0077] The white pigment may be a pigment dispersion in which the pigment is dispersed in advance with a pigment dispersant, or a microencapsulated pigment in which the pigment is coated with a resin.

[0078] The white pigment may be used alone or in combination of two or more kinds.

[0079] From the viewpoint of hiding power and the like, the amount of the white pigment is preferably 5 to 30% by mass, more preferably 8 to 20% by mass, and even more preferably 10 to 12% by mass, based on the total amount of the white ink.

[0080] In order to stably disperse the white pigment in the white ink, a pigment dispersant such as a polymer dispersant or a surfactant-type dispersant can be used.

[0081] Examples of commercially available polymer dispersants include the TEGO Disperse series manufactured by EVONIK, such as "TEGO Disperse 740W," "TEGO Disperse 750W," "TEGO Disperse 755W," "TEGO Disperse 757W," and "TEGO Disperse 760W," and the Solsperse series manufactured by Lubrizol Japan, such as "Solsperse 20000," "Solsperse 27000," "Solsperse 41000," "Solsperse 41090," "Solsperse 43000," "Solsperse 44000," and "Solsperse 46000." Examples include the JONCRYL series manufactured by BASF Japan Ltd., such as "JONCRYL 57," "JONCRYL 60," "JONCRYL 62," "JONCRYL 63," "JONCRYL 71," and "JONCRYL 501," and the like; manufactured by BYK Japan Co., Ltd., "DISPERBYK-102," "DISPERBYK-185," "DISPERBYK-190," "DISPERBYK-193," and "DISPERBYK-199," and the like; and manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., "Polyvinylpyrrolidone K-30" and "Polyvinylpyrrolidone K-90" (all trade names).

[0082] Examples of surfactant-type dispersants include anionic surfactants such as the Demol series manufactured by Kao Corporation, including "Demol P," "Demol EP," "Demol N," "Demol RN," "Demol NL," "Demol RNL," and "Demol T-45," and nonionic surfactants such as the Emulgen series manufactured by Kao Corporation, including "Emulgen A-60," "Emulgen A-90," "Emulgen A-500," "Emulgen B-40," "Emulgen L-40," and "Emulgen 420" (all trade names).

[0083] The pigment dispersants may be used alone or in combination of two or more.

[0084] When a pigment dispersant is used, its content in the ink varies depending on the type and is not particularly limited, but in general, the mass ratio of the active ingredient to the white pigment is preferably 0.005 to 0.5.

[0085] The white ink preferably contains water, and water may be the main solvent. The water is not particularly limited, but it is preferable that it contains as few ionic components as possible. In particular, from the viewpoint of the storage stability of the white ink, it is preferable that the content of polyvalent metal ions such as calcium is low. As the water, for example, ion-exchanged water, distilled water, ultrapure water, etc. may be used.

[0086] From the viewpoint of adjusting the ink viscosity, the water content is preferably 30 to 90% by mass, more preferably 40 to 85% by mass, and even more preferably 50 to 80% by mass, of the total amount of the white ink.

[0087] The white ink may contain a water-soluble organic solvent.

[0088] The water-soluble organic solvent can be selected from those described above for the pretreatment liquid.

[0089] Among these, glycols, glycerins, or combinations thereof are preferred from the viewpoints of adjusting ink viscosity and moisturizing properties. Preferred glycols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, and tripropylene glycol. Preferred glycerins are glycerin.

[0090] The water-soluble organic solvents may be used alone or in combination of two or more. When two or more water-soluble organic solvents are contained, the total content of the water-soluble organic solvents is preferably 10 to 50% by mass, more preferably 15 to 40% by mass, and even more preferably 15 to 30% by mass, relative to the total mass of the white ink.

[0091] The white ink may further contain a surfactant. The surfactant may be selected from those described above for the pretreatment liquid. The surfactant may be an anionic surfactant, a cationic surfactant, an amphoteric surfactant, or a nonionic surfactant, with nonionic surfactants being more preferred. Furthermore, either a low-molecular-weight surfactant or a high-molecular-weight surfactant may be used.

[0092] The content of the surfactant is preferably 0.1 to 5% by mass, and more preferably 0.2 to 2% by mass, relative to the total amount of the white ink.

[0093] The white ink may further contain a water-dispersible resin, a water-soluble resin, or a combination thereof. From the viewpoint of sufficiently fixing the pigment to the fabric and thereby obtaining high coloring properties with a small amount of pigment, it is preferable that the white ink contains at least one of a water-dispersible resin and a water-soluble resin.

[0094] Examples of water-soluble resins include polyvinyl alcohol, polyacrylic acid, neutralized polyacrylic acid, acrylic acid / maleic acid copolymer, acrylic acid / sulfonic acid copolymer, styrene / maleic acid copolymer, etc. These may be used alone or in combination of two or more.

[0095] The water-dispersible resin is preferably resin particles that can be dispersed in an aqueous solvent. The water-dispersible resin can be blended into the ink, for example, as an oil-in-water resin emulsion.

[0096] The water-dispersible resin may be a self-emulsifying resin in which a hydrophilic component is introduced to stably disperse it in water, or may be a resin that becomes water-dispersible by the use of an external emulsifier.

[0097] From the viewpoint of inkjet ejection properties, the average particle size of the water-dispersible resin is preferably 300 nm or less, more preferably 200 nm or less, and even more preferably 150 nm or less. For example, the average particle size of the water-dispersible resin may be in the range of 10 nm to 300 nm.

[0098] Here, the average particle size of the resin is a volume-based average particle size, and is a value measured by a light scattering method.

[0099] The water-dispersible resin may be anionic, cationic, nonionic, or amphoteric. From the viewpoint of more stably dispersing the water-dispersible resin in the aqueous ink, the water-dispersible resin is preferably anionic or nonionic.

[0100] The water-dispersible resin is preferably an anionic water-dispersible resin having an anionic functional group such as a carboxy group, a sulfo group, or a hydroxy group.

[0101] The type of water-dispersible resin used is preferably a resin that forms a transparent coating film. The water-dispersible resin can be blended as a resin emulsion when producing the ink.

[0102] Representative examples include urethane resins, (meth)acrylic resins, styrene / (meth)acrylic resins, polyester resins, olefin resins, vinyl chloride resins, vinyl acetate resins, melamine resins, amide resins, ethylene-vinyl chloride copolymer resins, styrene-(meth)acrylic resins, styrene-maleic anhydride copolymer resins, vinyl acetate-(meth)acrylic copolymer resins, vinyl acetate-ethylene copolymer resins, silicone resins, and composite resins thereof.

[0103] The water-dispersible resin is preferably a water-dispersible urethane resin, a water-dispersible polyester resin, or a combination thereof.

[0104] Examples of commercially available water-dispersible resins include "Superflex 470" (water-dispersible urethane resin) manufactured by Daiichi Kogyo Seiyaku Co., Ltd. and "Elitel KT9204" (water-dispersible polyester resin) manufactured by Unitika Ltd. (both are trade names).

[0105] The above-mentioned water-dispersible resins may be used alone or in combination of two or more.

[0106] The water-dispersible resin preferably has a nonvolatile content of 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, based on the total amount of the white ink. The water-dispersible resin preferably has a nonvolatile content of 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less, based on the total amount of the white ink. For example, the water-dispersible resin preferably has a nonvolatile content of 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 10 to 20% by mass, based on the total amount of the white ink.

[0107] The mass ratio of the nonvolatile content of the water-dispersible resin to the pigment is preferably 0.1 to 10, more preferably 1 to 3, per 1 pigment.

[0108] The total amount of the water-dispersible resin and the water-soluble resin is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, based on the total amount of the white ink, in terms of nonvolatile content. The total amount of the water-dispersible resin and the water-soluble resin is preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less, based on the total amount of the white ink, in terms of nonvolatile content. For example, the total amount of the water-dispersible resin and the water-soluble resin is preferably 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 10 to 20% by mass, based on the total amount of the white ink, in terms of nonvolatile content.

[0109] The total amount of the water-dispersible resin and the water-soluble resin is preferably 0.1 to 10, more preferably 1 to 3, in terms of the mass ratio of the nonvolatile content to the pigment.

[0110] The white ink may further contain other components such as a pH adjuster, a preservative, a rust inhibitor, an antifoaming agent, and an amine compound.

[0111] The method for producing the white ink is not particularly limited, and the ink can be produced by any known method. For example, all of the components are added to a stirrer such as a Three-One Motor or the like all at once or in portions, and dispersed, and if desired, the mixture is passed through a filter such as a membrane filter to obtain an ink.

[0112] From the viewpoint of storage stability of the ink, the pH of the white ink is preferably 7.0 to 10.0, and more preferably 7.5 to 9.0.

[0113] The viscosity of the white ink can be adjusted as appropriate, but from the standpoint of ejection properties, for example, it is preferable that the viscosity at 23° C. is 1 to 30 mPa·s.

[0114] Next, the above-mentioned color inks will be described.

[0115] In this embodiment, black ink, cyan ink, magenta ink, and yellow ink are used as color inks.

[0116] The color ink may contain, as a colorant, a pigment, a dye, or a combination thereof, and preferably contains a pigment.

[0117] The pigment preferably includes a non-white pigment.

[0118] Non-white pigments include organic pigments such as azo pigments, phthalocyanine pigments, polycyclic pigments, and dye lake pigments, as well as inorganic pigments such as carbon black and metal oxides. Azo pigments include soluble azo lake pigments, insoluble azo pigments, and condensed azo pigments. Phthalocyanine pigments include metal phthalocyanine pigments and metal-free phthalocyanine pigments. Polycyclic pigments include quinacridone pigments, perylene pigments, perinone pigments, isoindoline pigments, isoindolinone pigments, dioxazine pigments, thioindigo pigments, anthraquinone pigments, quinophthalone pigments, metal complex pigments, and diketopyrrolopyrrole (DPP). Carbon black includes furnace carbon black, lamp black, acetylene black, and channel black. These pigments may be used alone or in combination.

[0119] From the viewpoints of ejection stability and storage stability, the average particle size of the pigment particles in the ink is preferably 300 nm or less, more preferably 150 nm or less, and even more preferably 100 nm or less, as the volume-based average value in the particle size distribution measured by dynamic light scattering.

[0120] The non-white pigment may be a self-dispersing pigment, the details of which are as described above for the white pigment.

[0121] Preferred examples of self-dispersing pigments that can be used include the CAB-O-JET series manufactured by Cabot Corporation, such as "CAB-O-JET200," "CAB-O-JET300," "CAB-O-JET250C," "CAB-O-JET260M," "CAB-O-JET270," and "CAB-O-JET450C," and products manufactured by Orient Chemical Industries Co., Ltd., such as "BONJET BLACK CW-1," "BONJET BLACK CW-2," "BONJET BLACK CW-3," and "BONJET BLACK CW-4" (all trade names).

[0122] As the pigment, a microencapsulated pigment in which the pigment is coated with a resin may be used.

[0123] A pigment dispersion in which the pigment is previously dispersed with a pigment dispersant may be used. Commercially available pigment dispersions in which the pigment is dispersed with a pigment dispersant include, for example, the HOSTAJET series manufactured by Clariant and the FUJI SP series manufactured by Fuji Pigment Co., Ltd.

[0124] As the dye, water-soluble dyes and water-soluble dyes made water-soluble by reduction or the like can be preferably used from among basic dyes, acid dyes, direct dyes, soluble vat dyes, acid mordant dyes, mordant dyes, reactive dyes, vat dyes, sulfur dyes, etc. Also preferably used are disperse dyes such as azo-based, anthraquinone-based, azomethine-based, and nitro-based dyes. These may be used alone or in combination.

[0125] The coloring materials may be used alone or in combination of two or more.

[0126] From the viewpoint of print density and ink viscosity, the content of the color material is preferably 0.1 to 20% by mass, more preferably 1 to 15% by mass, and even more preferably 2 to 7% by mass, based on the total amount of color ink.

[0127] When a pigment is used as a coloring material in a color ink, a pigment dispersant, typically a polymer dispersant, a surfactant-type dispersant, etc., can be used to stably disperse the pigment in the color ink. The pigment dispersant can be selected from those described above for the white ink, for example.

[0128] When a pigment dispersant is used, the content in the color ink varies depending on the type and is not particularly limited, but in general, the mass ratio of the active ingredient to the pigment is preferably 0.005 to 0.5.

[0129] The color ink preferably contains water. The color ink may contain a water-soluble organic solvent in addition to or instead of water. Details of the water and the water-soluble organic solvent are as described above for the white ink. The water-soluble organic solvent may be selected from those described above for the white ink, for example.

[0130] From the viewpoint of adjusting the ink viscosity, the water content is preferably 20% by mass to 80% by mass, and more preferably 30% by mass to 70% by mass, based on the total amount of the color ink.

[0131] The amount of the water-soluble organic solvent is preferably 5 to 50% by mass, and more preferably 10 to 30% by mass, based on the total amount of the color ink.

[0132] The color ink may further contain a surfactant. The surfactant may be selected from those described above for the white ink. Among these, nonionic surfactants are preferred, and acetylene-based surfactants such as acetylene glycol-based surfactants are more preferred.

[0133] The amount of the surfactant in terms of active ingredients is preferably 0.1 to 10% by mass, more preferably 0.2 to 5% by mass, based on the total amount of the color ink.

[0134] The color ink may further contain a resin such as a water-dispersible resin or a water-soluble resin. For example, by including a fixing resin in the color ink, the fixation of the printed image to the fabric and the coating strength of the image can be further improved. From the viewpoint of obtaining ejection properties and storage stability suitable for inkjet inks, the color ink preferably contains a water-dispersible resin. The water-dispersible resin is preferably blended into the color ink in the form of a water-in-oil emulsion and is preferably dispersible in the color ink in the form of resin particles. The water-dispersible resin can be selected from those described above for the white ink, and may be a water-dispersible urethane resin, other water-dispersible resins, or a combination thereof.

[0135] The content of the water-dispersible resin is preferably 1 to 30% by mass, more preferably 3 to 30% by mass, and even more preferably 5 to 20% by mass, based on the total amount of the color ink.

[0136] The color ink may further contain a crosslinking agent. When the color ink contains a crosslinking agent, the coating strength of the image can be further increased. By increasing the coating strength, cracking of the image can be further suppressed even after washing the printed material. Examples of crosslinking agents include carbodiimide compounds, isocyanate compounds, and oxazoline compounds.

[0137] The content of the crosslinking agent is preferably 0.1 to 5% by mass, and more preferably 0.2 to 2% by mass, based on the total amount of the color ink.

[0138] The color ink may further contain other components such as a pH adjuster, a preservative, a rust inhibitor, and an antifoaming agent.

[0139] The method for producing the color ink is not particularly limited, and the ink can be produced by any known method. For example, all the components are added to a stirrer such as a Three-One Motor all at once or in portions, and dispersed, and if desired, the mixture is passed through a filter such as a membrane filter to obtain an ink.

[0140] The pH of the color ink is preferably 7.0 to 10.0, more preferably 7.5 to 9.0, from the viewpoint of storage stability of the ink.

[0141] The viscosity of the color ink can be adjusted as appropriate, but from the viewpoint of ejection properties, for example, the viscosity at 23° C. is preferably 1 to 30 mPa·s.

[0142] Next, the operation of the printing system 1 will be described with reference to the flowchart of FIG.

[0143] Here, the operation of the printing system 1 when printing an image including the above-mentioned main image and additional image will be described.

[0144] In step S1 of FIG. 3, the terminal device 3 transmits print data for printing an image including a main image and an additional image to the printing device 2 in response to a user's operation to instruct printing of the image.

[0145] An example of an application screen for instructing printing of an image including a main image and additional images is shown in Fig. 4. An application screen 41 shown in Fig. 4 is displayed on the display unit of the terminal device 3.

[0146] As shown in FIG. 4, an application screen 41 displays a document display section 42 that displays an image of a document to be printed, and a print button 43 for issuing a print instruction.

[0147] The user can specify an image to be printed as an additional image from among the images of the original displayed on the original display section 42 using a specification frame 44 by operating the specification frame 44 .

[0148] When an image is designated in the designation frame 44 and the print button 43 is pressed, the terminal device 3 transmits print data to the printing device 2 for printing an image including the image designated in the designation frame 44 as an additional image and the remaining images as main images. The print data includes information indicating the area of ​​the additional image within the image to be printed.

[0149] Returning to FIG. 3, in step S2, the control unit 14 of the printing device 2 executes printing based on the print data.

[0150] Specifically, first, the control unit 14 controls the conveying unit 12 to move the fabric placed on the support unit to the initial printing position. Here, the fabric is placed on the support unit of the conveying unit 12 by a user's operation or the like.

[0151] Next, the control unit 14 moves the head unit 21 in the main scanning direction, and causes the pretreatment liquid ejection head 31 to eject the pretreatment liquid onto the same area on the fabric as the area where the image based on the print data is formed with color inks, thereby completing the ejection operation for the first pass.

[0152] Next, the control unit 14 moves the cloth backward by a predetermined distance using the conveying unit 12. Next, the control unit 14 moves the head unit 21 in the direction opposite to the direction of the ejection operation in the previous pass, and ejects the pretreatment liquid from the pretreatment liquid ejection head 31 and the white ink from the white ink ejection head 32.

[0153] Here, the control unit 14 ejects the white ink onto the same area on the fabric as the area onto which the pretreatment liquid was ejected in the previous pass. The control unit 14 controls the ejection of the white ink so that it is performed by the wet-on-wet method.

[0154] Next, the control unit 14 causes the conveying unit 12 to move the cloth backward by a predetermined distance. Next, the control unit 14 causes the head unit 21 to move in the opposite direction to the ejection operation of the previous pass, while ejecting the pretreatment liquid from the pretreatment liquid ejection head 31 and the white ink from the white ink ejection head 32, and simultaneously ejecting color inks from the color ink ejection head 33 onto the area on the cloth onto which the pretreatment liquid and white ink have been ejected up to the previous pass, thereby forming an image. The control unit 14 controls the ejection of the color inks to be performed by the wet-on-wet method.

[0155] The control unit 14 alternately repeats the movement of the head unit 21 in the main scanning direction and the movement toward the rear of the cloth as described above, and executes the steps of ejecting pretreatment liquid onto the cloth, ejecting white ink onto the area on the cloth onto which the pretreatment liquid has been ejected, and ejecting color ink onto the area onto which the pretreatment liquid and white ink have been ejected, thereby printing an image including a main image and an additional image.

[0156] At this time, the control unit 14 prints the main image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area where the main image of the fabric is printed is equal to or higher than a predetermined first level, as described above. Also, the control unit 14 prints the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area where the additional image of the fabric is printed is equal to or lower than a predetermined second level that is lower than the first level.

[0157] Here, as described above, for example, the first level can be set to discoloration / fading grade 3 or higher in washing fastness according to JIS L 0844 A-2, and the second level can be set to grade 1.

[0158] As described above, it is preferable that the weight ratio of the pretreatment liquid to the ink used to print the main image is 0.4 or less, and the weight ratio of the pretreatment liquid to the ink used to print the additional image is 0.55 or more.

[0159] As mentioned above, washing fastness mainly depends on the weight ratio of the pretreatment liquid to the ink. In contrast, if the weight ratio is the same, the greater the amount of ink, the stronger the ink coating film, and as a result, the higher the washing fastness. Because the resin contained in the ink affects the coating performance, the greater the amount of ink, the greater the amount of resin contained in the ink, and therefore the stronger the ink coating film. Furthermore, the greater the amount of pretreatment liquid, the more likely the ink is to remain on the surface of the fabric, improving color development, but the adhesion between the fabric and the ink decreases, resulting in lower washing fastness.

[0160] For this reason, when printing the main image, using a larger amount of ink is effective in improving washing fastness. In contrast, when using color inks in amounts above a certain level, the greater the amount, the duller the image and the lower the image quality. For white ink, the greater the amount, the better the whiteness and hiding power, and the higher the image quality of images printed with color inks. For this reason, when printing the main image, using a larger amount of white ink than color ink is preferable, as this makes it easier to improve washing fastness while suppressing deterioration in image quality.

[0161] When printing of the image on the fabric by the printing device 2 is completed, the drying device 4 dries the printed fabric in step S3. As a result, a printed item, which is fabric on which an image is formed, is produced. This completes the series of operations.

[0162] An example of unwashed cloth (printed material) on which an image has been printed by the above-described operation is shown in Fig. 5. In the example of Fig. 5, a main image 52 and an additional image 53 are printed on a T-shirt 51 formed from the cloth.

[0163] By washing the T-shirt 51 in FIG. 5 at least once, only the additional image 53 out of the main image 52 and the additional image 53 disappears as shown in FIG.

[0164] As described above, in the printing device 2, the control unit 14 controls the pretreatment liquid ejection head 31, the white ink ejection head 32, and the color ink ejection head 33 to print the main image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area where the main image of the cloth is printed is at or above a first level, and to print the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area where the additional image of the cloth is printed is at or below a second level that is lower than the first level.

[0165] In this way, by adjusting the weight ratio of the pretreatment liquid to the ink, it is possible to adjust the wash fastness of the area of ​​the fabric where the main image is printed and the area where the additional image is printed, without using different types of ink for the main image and the additional image. Therefore, it is possible to produce a printed item in which it is possible to erase only the additional image, which is a part of the printed (printed) image, without using additional ink.

[0166] The first level may be set to colorfastness to washing in accordance with JIS L 0844 A-2, at grade 3 or higher, and the second level may be set to grade 1. This makes it possible to print the main image as an image that will not fade even when washed, and the additional image as an image that will fade when washed.

[0167] Furthermore, it is preferable that the weight ratio of the pretreatment liquid to the ink used to print the main image is 0.4 or less, and the weight ratio of the pretreatment liquid to the ink used to print the additional image is 0.55 or more. This makes it possible to set the weight ratios of the pretreatment liquid to the ink used to print the main image and the additional image so that the main image will not fade even when washed, and the additional image will fade when washed.

[0168] Note that the ejection of white ink may be omitted when printing the additional image. In this case, the control unit 14 controls the color ink ejection head 33 to eject color inks onto the fabric onto which the pretreatment liquid has been ejected, omitting the ejection of white ink from the white ink ejection head 32, to print the additional image.

[0169] As described above, when printing the main image, it is preferable to use a larger amount of white ink than color ink, as this makes it easier to improve washing fastness while suppressing degradation of image quality. In contrast, when printing additional images, which do not require higher image quality than the main image and have lower washing fastness, the ejection of white ink can be omitted. By omitting the ejection of white ink, it is possible to reduce white ink consumption.

[0170] In the above-described embodiment, the pretreatment liquid and the white ink are ejected onto the same region on the fabric as the region on which the image is formed with the color inks. However, at least one of the region on which the pretreatment liquid is ejected and the region on which the white ink is ejected may have a portion that does not overlap with the region on the fabric on which the image is formed with the color inks. Furthermore, the region on which the pretreatment liquid is ejected may be an area that includes the region on which the white ink is ejected, but is larger than the region on which the white ink is ejected.

[0171] Furthermore, in the above-described embodiment, printing is performed by ejecting white ink and color inks using a wet-on-wet method, but a wet-on-dry method may also be used.

[0172] In the above-described embodiment, the printing device 2 is a serial inkjet printing device, but it may also be a line inkjet printing device. Furthermore, the pretreatment liquid may be ejected in a separate device from the white ink and the color inks to produce a printed item.

[0173] The present invention is not limited to the above-described embodiments, and the components can be modified and embodied in practice without departing from the spirit of the invention. Furthermore, various inventions can be created by appropriately combining multiple components disclosed in the above-described embodiments. For example, some components may be omitted from all the components shown in the embodiments.

[0174] [Note] The present application discloses the following inventions.

[0175] (Appendix 1) a pretreatment liquid ejection unit that ejects a pretreatment liquid that aggregates ink; an ink ejection unit that ejects ink; a control unit that controls the pretreatment liquid ejection unit to eject the pretreatment liquid onto the cloth, and the ink ejection unit to eject ink onto the cloth onto which the pretreatment liquid has been ejected, thereby printing a main image and an additional image; The control unit printing the main image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area of ​​the fabric where the main image is printed is equal to or higher than a predetermined first level; a printing device controlling the pretreatment liquid ejection unit and the ink ejection unit to print the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of an area of ​​the fabric where the additional image is printed is equal to or lower than a predetermined second level that is lower than the first level.

[0176] (Appendix 2) The first level is grade 3 or higher in colorfastness to washing according to JIS L 0844 A-2, 2. The printing device according to claim 1, wherein the second level is Grade 1 in colorfastness to washing in accordance with JIS L 0844 A-2.

[0177] (Appendix 3) 3. The printing device according to claim 1, wherein the control unit sets a weight ratio of the pretreatment liquid to the ink used to print the main image to 0.4 or less, and a weight ratio of the pretreatment liquid to the ink used to print the additional image to 0.55 or more.

[0178] (Appendix 4) The ink ejection unit a white ink ejection unit that ejects white ink; a color ink ejection unit that ejects color inks, The control unit the white ink ejection unit ejects white ink onto the cloth onto which the pretreatment liquid has been ejected, and the color ink ejection unit ejects color ink onto the cloth onto which the pretreatment liquid and the white ink have been ejected, thereby printing the main image; 4. The printing device according to claim 1, wherein the printing device is controlled so that the white ink ejection unit does not eject white ink onto the fabric onto which the pretreatment liquid has been ejected, and the color ink ejection unit ejects color inks to print the additional image.

[0179] (Appendix 5) a step of ejecting a pretreatment liquid onto a cloth that aggregates the ink, and then ejecting ink onto the cloth onto which the pretreatment liquid has been ejected to print a main image; a step of ejecting a pretreatment liquid onto the fabric, and ejecting ink onto the fabric onto which the pretreatment liquid has been ejected to print an additional image; In the step of printing the main image, the weight ratio of the pretreatment liquid to the ink is adjusted so that the washing fastness of the area of ​​the fabric where the main image is printed is equal to or higher than a predetermined first level; a weight ratio of a pretreatment liquid to an ink being adjusted so that the washing fastness of an area of ​​the fabric where the additional image is printed is equal to or lower than a second level that is lower than the first level, in the step of printing the additional image. [Example]

[0180] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0181] <Production of pretreatment liquid> The raw materials of the pretreatment liquid are shown in Table 1. The blending ratio of the raw materials in Table 1 includes the amount of solvents, etc., if any, contained in the material.

[0182] The raw materials were mixed in the proportions shown in Table 1 to obtain a pretreatment liquid.

[0183] [Table 1]

[0184] <White ink production> The raw materials for the white ink are shown in Table 2. The blending ratios of the raw materials in Table 2 include the amounts of solvents, etc., if any, contained in the materials.

[0185] The materials were mixed according to the blending ratios shown in Table 2 and filtered through a membrane filter with a pore size of 3 μm to obtain a white ink.

[0186] [Table 2]

[0187] The white pigment dispersions shown in Table 2 were obtained by the following method.

[0188] (Production of White Pigment Dispersion) 350 g of titanium dioxide "TIPAQUE R-980" (manufactured by Ishihara Sangyo Kaisha) was used as the white pigment, and 17.5 g (3.5 g of active ingredient) of "Demol P" (manufactured by Kao Corporation) was used as the pigment dispersant. These were mixed with 632.5 g of ion-exchanged water, and dispersed with 0.5 mm diameter zirconia beads using a bead mill (manufactured by Shinmaru Enterprises, DYNO-MILL KDL A type) at a filling rate of 80% and a residence time of 2 minutes, yielding a pigment dispersion (pigment content 35% by mass). This was designated as the white pigment dispersion.

[0189] <Color ink manufacturing> The raw materials for the color inks are shown in Table 3. The blending ratios of the raw materials in Table 1 include solvents, etc., if any, in the materials. Here, cyan ink was used as the color ink.

[0190] Each material was mixed according to the blending ratio shown in Table 3, and filtered through a membrane filter with a pore size of 3 μm to obtain a color ink.

[0191] [Table 3]

[0192] <Manufacturing of printed items> Using the pretreatment liquid, white ink, and color ink (cyan ink) produced as described above, printed textiles of Examples 1 to 6 and Comparative Example were produced as follows.

[0193] Using the inkjet printer "MMP-8130" manufactured by Mastermind Co., Ltd., in each of the two regions A and B of the cloth, a pretreatment liquid, white ink, and color ink were ejected in this order to print an image depicting the character "beautiful" in 36-point / Mayrio font.

[0194] In each of Examples 1 to 6 and the Comparative Example, the ejection amounts of the inks (color ink + white ink) in regions A and B, the ejection amount of the color ink, the ejection amount of the white ink, and the weight ratio of the pretreatment liquid to the ink are as shown in Tables 4 to 6. Here, in region B of Example 4, the ejection of white ink is omitted (the ejection amount of white ink is 0).

[0195] The materials of the cloth in each of Examples 1 to 6 and the Comparative Example are as shown in Tables 4 to 6.

[0196] In Examples 1, 4, and 5 where the material of the cloth is cotton, the printed cloth was dried at 170 °C for 90 seconds using a heat press to obtain a dyed product. In Examples 2, 3, 6 and the Comparative Example where the material of the cloth is polyester, the printed cloth was dried at 120 °C for 120 seconds using a heat press to obtain a dyed product.

[0197] <Evaluation of washing fastness> As the washing fastness of the dyed products in Examples 1 to 6 and the Comparative Example, the color fading and discoloration due to washing were evaluated according to JIS L 0844 A-2. The results are shown in Tables 4 to 6. The color fading and discoloration are evaluated in 9 grades of 1st, 1-2nd, 2nd, 2-3rd, 3rd, 3-4th, 4th, 4-5th, and 5th, and the 5th grade has the highest washing fastness.

[0198] [Table 4]

[0199] [Table 5]

[0200] [Table 6]

[0201] As shown in Tables 4 and 5, in region A of Examples 1 to 6, where the weight ratio of the pretreatment liquid to the ink was 0.4 or less, discoloration was grade 3 or higher, and the image in region A exhibited sufficient washing fastness to be considered an image that would not fade even when the fabric was washed.

[0202] In contrast, in the comparative example, region A, where the weight ratio of the pretreatment liquid to the ink exceeded 0.4, the discoloration was less than grade 3, and the image in region A did not have sufficient washing fastness to be considered an image that would not fade even when the fabric was washed.

[0203] In addition, in region B of Examples 1 to 6, where the weight ratio of pretreatment liquid to ink was 0.55 or more, discoloration was grade 1 or less, and the image in region B exhibited a washing fastness that could be considered to be an image that would disappear when the fabric was washed.

[0204] In contrast, in region B of the comparative example, where the weight ratio of the pretreatment liquid to the ink was less than 0.4, the discoloration exceeded grade 1, and the image in region B did not exhibit a washing fastness that would allow it to be considered an image that would disappear when the fabric was washed. [Explanation of symbols]

[0205] 1 Printing System 2 Printing device 3 Terminal Devices 4 Drying equipment 11 Printing Department 12 Conveyor 13 Communications Department 14 Control Unit 21 Head Unit 22 Rail section 31 Pre-treatment liquid ejection head 32 White ink ejection head 33 Color ink ejection head 34 Head holder 41 App screen 42 Original display area 43 Print button 44 designated slots 51 T-shirt 52 Main Image 53 additional images

Claims

1. a pretreatment liquid ejection unit that ejects a pretreatment liquid that aggregates ink; an ink ejection unit that ejects ink; a control unit that controls the pretreatment liquid ejection unit to eject the pretreatment liquid onto the cloth, and the ink ejection unit to eject ink onto the cloth onto which the pretreatment liquid has been ejected, thereby printing a main image and an additional image; The control unit printing the main image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area of ​​the fabric where the main image is printed is equal to or higher than a predetermined first level; a printing device controlling the pretreatment liquid ejection unit and the ink ejection unit to print the additional image by adjusting the weight ratio of the pretreatment liquid to the ink so that the washing fastness of the area of ​​the fabric where the additional image is printed is equal to or lower than a predetermined second level which is lower than the first level.

2. The first level is grade 3 or higher in colorfastness to washing according to JIS L 0844 A-2, 2. The printing device according to claim 1, wherein the second level is Grade 1 in colorfastness to washing in accordance with JIS L 0844 A-2.

3. 3. The printing device according to claim 1, wherein the control unit sets a weight ratio of the pretreatment liquid to the ink used to print the main image to 0.4 or less, and a weight ratio of the pretreatment liquid to the ink used to print the additional image to 0.55 or more.

4. The ink ejection unit a white ink ejection unit that ejects white ink; a color ink ejection unit that ejects color inks, The control unit the white ink ejection unit ejects white ink onto the cloth onto which the pretreatment liquid has been ejected, and the color ink ejection unit ejects color ink onto the cloth onto which the pretreatment liquid and the white ink have been ejected, thereby printing the main image; 3. The printing device according to claim 1, wherein the printing device is controlled so that the white ink ejection unit does not eject white ink onto the fabric onto which the pretreatment liquid has been ejected, and the color ink ejection unit ejects color inks to print the additional image.

5. a step of ejecting a pretreatment liquid onto a cloth that aggregates the ink, and then ejecting ink onto the cloth onto which the pretreatment liquid has been ejected to print a main image; a step of ejecting a pretreatment liquid onto the fabric, and ejecting ink onto the fabric onto which the pretreatment liquid has been ejected to print an additional image; In the step of printing the main image, the weight ratio of the pretreatment liquid to the ink is adjusted so that the washing fastness of the area of ​​the fabric where the main image is printed is equal to or higher than a predetermined first level; a weight ratio of a pretreatment liquid to an ink being adjusted so that a region of the fabric where the additional image is printed has a washing fastness of not more than a second level that is lower than the first level, in the step of printing the additional image.

Images