Printer and printing method

Abstract

To provide a printer that eliminates oozing marks remaining after DTG printing and has high productivity.SOLUTION: A printer includes: a pretreatment liquid application section which applies pretreatment liquid to a prescribed region on a material to be printed having permeability; a white ink application section which applies white ink to a prescribed region in a region to which the pretreatment liquid is applied and forms a base by the white ink; a color ink application section which applies color ink to a prescribed region on the base by the white ink and forms a color image; and a colorless liquid application section which applies colorless liquid containing water to a prescribed region including at least a part of an oozing mark region around an image formation region. The printer adjusts a region to which the colorless liquid is applied according to timing for applying the colorless liquid.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a printing apparatus and a printing method.

Background Art

[0002] DTG (Direct to Garment) printing, which uses inkjet technology to directly eject ink onto fabric substrates for printing, is already known. In DTG printing, in order to firmly fix the colorant to the fabric substrate to be printed, there is a step of applying a pretreatment liquid before printing. By applying the pretreatment liquid, inks containing white pigments that are difficult to fix to fabric fibers and polyester fibers to which ink is difficult to fix can be used.

[0003] Conventionally, after applying the pretreatment liquid, it was dried once with a heat press machine and then printed, and the heat press was performed again to fix the ink. In recent years, for the purpose of shortening this working process and increasing productivity, a printing apparatus incorporating a pretreatment liquid ejection head has been developed. Since the application of the pretreatment liquid and printing are performed with the same apparatus, it is possible to accurately apply the pretreatment liquid to the area where the image is to be printed, and there is also an advantage that the amount of pretreatment liquid used can be reduced.

[0004] In a printing apparatus incorporating a pretreatment liquid ejection head, since there is no drying process until the printing of the image is completed, the printed surface of the fabric substrate is in a wet state, and the wet range expands according to the amount of liquid (pretreatment liquid and ink) adhering. When printing on a white fabric substrate, only the pretreatment liquid and color ink need to be used, but when printing on a colored fabric substrate (black, red, blue, green, etc.), accurate color representation cannot be achieved due to the influence of the fabric substrate color even if color ink is printed directly. Therefore, in order to eliminate the influence of the fabric substrate color, a large amount of white ink is printed as a base for the color ink to conceal the fabric substrate color. If the amount of white ink is small, the fabric substrate color will show through and affect the color tone of the printed image, and the printed surface including the white ink base will peel off due to friction or washing.

[0005] When printing on white cloth fabric, since less liquid is used, bleeding during printing does not pose a problem. On the other hand, when printing on colored cloth fabric, there is a problem that bleeding marks occur outside the printed area due to the bleeding of a large amount of white ink used as the base. The factors causing the bleeding marks are organic solvents such as wetting agents contained in the pretreatment liquid and ink. In particular, since wetting agents have a high boiling point, they cannot be removed by evaporation even by heat treatment using a heat press machine or the like performed in DTG printing. Since wetting agents have high water solubility, the bleeding marks can be removed by washing. However, in that case, waste liquid is generated by washing, which not only increases the environmental load but also requires additional processes such as drying and ironing, resulting in a significant decrease in productivity.

[0006] As a technique for eliminating bleeding marks, for example, a pretreatment apparatus described in Patent Document 1 is disclosed. In Patent Document 1, it is disclosed that a pretreatment agent (PPT) for pretreatment to improve bleeding caused by the pretreatment agent (PT) can solve the problem that a gelation trace remains after reacting with the PT by using another pretreatment agent.

[0007] However, the pretreatment apparatus disclosed in Patent Document 1 prevents bleeding marks caused by uneven application of the PT itself and the interaction between the PT and the ink, and cannot eliminate bleeding marks that occur when a large amount of white ink is used as the base on colored cloth fabric.

Summary of the Invention

Problems to be Solved by the Invention

[0008] An object of the present invention is to achieve the following. That is, an object of the present invention is to provide a printing apparatus that eliminates bleeding marks remaining after DTG printing and has high productivity.

Means for Solving the Problems

[0009] One aspect of the present invention is a printing apparatus having a pretreatment liquid applying unit that applies a pretreatment liquid to a predetermined area on a permeable printed material, a white ink applying unit that applies white ink to a predetermined area on the area where the pretreatment liquid has been applied to form a base with the white ink, a color ink applying unit that applies color ink to a predetermined area on the base formed by the white ink to form a color image, and a colorless liquid applying unit that applies a colorless liquid containing water to a predetermined area including at least a part of the bleeding mark area around the image forming area, and adjusting the area to which the colorless liquid is applied according to the timing of applying the colorless liquid.

Advantages of the Invention

[0010] According to the present invention, it is possible to provide a printing apparatus that eliminates bleeding marks remaining after DTG printing and has high productivity.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0012] The printing apparatus of the present invention includes a pretreatment liquid applying unit that applies a pretreatment liquid to a predetermined area on a permeable object to be printed, a white ink applying unit that applies white ink to the area where the pretreatment liquid is applied to form a base with the white ink, a color ink applying unit that applies color ink to a predetermined area on the base formed by the white ink to form a color image, and a colorless liquid applying unit that applies a colorless liquid containing water to a predetermined area including at least a part of the bleeding trace area around the image forming area, and adjusts the area to which the colorless liquid is applied according to the timing of applying the colorless liquid. Further, if necessary, a heat treatment unit that performs heat treatment after forming an image may be further provided, and other units may be provided as necessary. Here, regions such as a predetermined region on a permeable printed material, a region to which the pretreatment liquid is applied, a predetermined region on the base with the white ink, and a predetermined region including at least a part of the bleeding trace region around the image forming region, etc. include an actually formed region, a region planned to be formed, or a region preset (stored) in a storage device of a computer (control device), etc., and also include combinations thereof.

[0013] The printing method of the present invention includes a pretreatment liquid application step of discharging a pretreatment liquid onto a predetermined region on a permeable printed material, a white ink application step of applying white ink to the region to which the pretreatment liquid is applied to form a base with the white ink, a color ink application step of applying color ink to a predetermined region on the base with the white ink to form a color image, and a colorless liquid application step of applying a colorless liquid containing water to a predetermined region including the bleeding trace region around the image forming region, and adjusts the region to which the colorless liquid is applied according to the timing of applying the colorless liquid. Further, if necessary, a heat treatment step of performing heat treatment after forming an image is further included, and other steps may be included as necessary. The other steps may be performed at any timing as long as the gist of the present invention is not impaired.

[0014] The printing method of the present invention can be preferably implemented by the printing apparatus of the present invention. The pretreatment liquid application step can be performed by a pretreatment liquid application unit, the white ink application step can be performed by a white ink application unit, the color ink application step can be performed by a color ink application unit, the colorless liquid application step can be performed by a colorless liquid application unit, and the heat treatment step can be performed by a heat treatment unit.

[0015] In addition, the "permeable printed material" in the present invention is a printed material characterized in that the pretreatment liquid and ink applied to the surface penetrate to the inside, and specifically, a cloth fabric is exemplified. The cloth fabric refers to a form in which fibers are made into a woven fabric, knitted fabric, woven cloth, non-woven fabric, etc., and there is no limitation on the thickness of the fibers and the size of the mesh. The fiber is not particularly limited and can be appropriately selected according to the purpose. For example, natural fiber, chemical fiber, biodegradable fiber, or a blended fiber thereof can be mentioned.

[0016] Examples of the natural fiber include fibers made of cotton, hemp, wool, silk, etc., or a blended fiber thereof.

[0017] Examples of the chemical fiber include regenerated fiber, synthetic fiber, semi-synthetic fiber, or a blended fiber thereof.

[0018] Examples of the regenerated fiber include fibers made of viscose, lyocell, polynosic, rayon, cupra, etc., or a blended fiber thereof.

[0019] Examples of the synthetic fiber include fibers made of polypropylene, polyester, acetate, triacetate, polyurethane, polyamide, polyimide, acrylic, polyvinyl alcohol, polyvinyl chloride, nylon, Nomex (registered trademark) (manufactured by Dupon), Kevlar (registered trademark) (manufactured by Dupon), etc., or a blended fiber thereof.

[0020] Examples of the semi-synthetic fiber include fibers made of acetate, diacetate, triacetate, etc., or a blended fiber thereof.

[0021] Examples of the biodegradable fiber include fibers made of polylactic acid, etc.

[0022] The present invention is characterized in that it can eliminate bleeding marks caused by the organic solvent contained in the white ink used in a large amount as a base, and the "printable material having permeability" is preferably a colored cloth fabric. Hereinafter, the present invention will be described using an example in which the "printable material having permeability" is a colored cloth fabric. Here, in the present invention, the "colored cloth fabric" refers to cloth fabrics other than white cloth fabrics, and black cloth fabrics are also included in the colored cloth fabrics. Note that although bleeding may occur with the pretreatment liquid and color ink even in the case of white cloth fabrics, usually, the marks are often not noticeable and do not pose a problem. However, if the marks are noticeable even in the case of white cloth fabrics, white may be included in the colored cloth fabrics.

[0023] Hereinafter, the printing apparatus of the present invention will be described in detail.

[0024] (Pretreatment liquid application unit) The pretreatment liquid application unit performs a pretreatment liquid application step of applying a pretreatment liquid to a predetermined area including the image formation area on the colored cloth fabric. By applying the pretreatment liquid, the ink is more likely to be fixed on the colored cloth fabric, and it becomes possible to form a base layer using a large amount of white ink.

[0025] Here, the "image formation area" refers to the area occupied by the image formed by the white ink and the color ink, including the base layer formed by the white ink formed by the white ink application unit described later, and is the same area as the area where the white ink is applied. However, if it is desired to form an image only with white ink, the "image formation area" may be formed only with white ink. If there is an area where it is desired to form an image using the same color as the colored cloth fabric, it is not necessary to apply white ink or color ink, and that area may also be regarded as the "image formation area".

[0026] The pretreatment liquid in the present invention contains a flocculant in order to fix the ink on the colored cloth fabric. Here, the "flocculant" refers to a component that causes flocculation or thickening in the white ink or color ink when the pretreatment liquid comes into contact with the white ink or color ink. Specifically, for example, components that flocculate water-dispersible particles such as color materials or resins contained in the white ink or color ink can be mentioned. By applying such a pretreatment liquid containing a flocculant onto the colored cloth fabric, the white ink in contact with the pretreatment liquid can be firmly fixed on the colored cloth fabric, and a base layer made of white ink can be formed.

[0027] The pretreatment liquid application unit is not particularly limited and can be appropriately selected according to the purpose. For example, an inkjet head, a sprayer, a hand spray, a coating roller, a brush, etc. can be mentioned. However, from the viewpoint of being easily incorporated into the same apparatus as the white ink application unit, color ink application unit, and colorless liquid application unit described later, an inkjet head is preferable.

[0028] When an inkjet head is used as the pretreatment liquid application unit, the pretreatment liquid application unit, the white ink application unit, color ink application unit, and colorless liquid application unit described later can be incorporated into the same apparatus, and the apparatus can be miniaturized. Further, by incorporating the pretreatment liquid application unit, the white ink application unit, color ink application unit, and colorless liquid application unit described later into the same apparatus and controlling them, it becomes possible to accurately apply the pretreatment liquid according to the area where the ink is applied, and it becomes possible to reduce the amount of the pretreatment liquid used.

[0029] The pretreatment liquid may be applied only to the image formation area, or may be applied not only to the image formation area but also to the area around the image formation area. In the present invention, the area around the image formation area to which the pretreatment liquid is applied is called the "overflow area". Further, the entire area to which the pretreatment liquid is applied, including the image formation area and the overflow area, is called the "pretreatment liquid application area".

[0030] When the pretreatment liquid is applied only to the image formation area, it becomes possible to reduce the amount of the pretreatment liquid used. When the pretreatment liquid is applied not only to the image formation area but also to the overflow area, it is possible to prevent insufficient color development of the ink due to displacement of the landing positions of the pretreatment liquid and the ink.

[0031] (White Ink Application Unit and Color Ink Application Unit) The white ink application unit performs a white ink application step of applying white ink to a predetermined area on the area where the pretreatment liquid has been applied to form a base with the white ink. The color ink application unit performs a color ink application step of applying color ink to a predetermined area on the base formed by the white ink to form a color image. Before the white ink application step and the color ink application step, by applying a pretreatment liquid in the pretreatment liquid application step, the white ink and the color ink are more likely to be fixed on the colored fabric base fabric.

[0032] As the white ink application part and the color ink application part, an inkjet head is usually used.

[0033] The role of the white ink as a base is as follows. (1) It cancels out the fabric color and surface texture of the colored fabric base fabric, ensuring the whiteness and smoothness as a canvas. It also bears the expression of the white part of the image. (2) As an intermediate layer, it physically receives the color ink. (1) is necessary to express the correct color and gradation in color ink printing, and (2) inevitably plays the role of a base as an intermediate layer due to the process order. However, in order to connect the color printing surface to the fabric, the layer of white ink needs to penetrate deep into the fibers of the colored fabric base fabric to become a firm base. In order to ensure the whiteness as color development, the smoothness as a surface, and the fastness, it is preferable to apply white ink in an amount more than four times that of the color ink.

[0034] Note that the white ink in the present invention is a liquid composition that forms a white image by being applied to an object to be printed. "White" is a color generally referred to as white and white in the common social concept, and includes those slightly colored. Also, the color ink in the present invention is a liquid composition that forms a color image by being applied to an object to be printed. "Color" represents a color not included in the above "white", and includes, for example, black, cyan, magenta, and yellow.

[0035] White ink and color ink usually contain an organic solvent as a wetting agent. A wetting agent is a component for moisturizing and preventing drying, and examples thereof include glycerin and propanediol. When an inkjet head is used as the ink application unit, since the ink contains a wetting agent, drying of the ink on the nozzle surface is prevented, and the ejection stability of the ink is improved. On the other hand, the wetting agent is a high-boiling component and remains even after the heat treatment for fixing the ink on the colored fabric ground, so it is one of the main causes of bleeding marks generated around the image formation area. In the present invention, the area where bleeding marks occur around the image formation area is called the "bleeding mark area".

[0036] (Colorless liquid application unit) The colorless liquid application unit performs a colorless liquid application step of applying a colorless liquid containing water to a predetermined area including the bleeding mark area around the image formation area. Since the organic solvent contained in the ink, that is, the wetting agent, has high water solubility, it dissolves in the colorless liquid containing water and is diluted, so that the bleeding marks become thin enough not to be recognized.

[0037] Here, the colorless liquid application step in the present invention is a technique different from the conventional techniques of "humidity conditioning" and "cleaning" as described below. "Humidity conditioning" is a process of spraying a small amount of moisture over the entire printing environment or the entire fabric before printing. By humidity conditioning, wrinkles on the fabric can be removed, and uneven ink penetration can be eliminated by making the moisture content on the fabric uniform. Also, when the entire printing environment is humidity-conditioned, drying of the inkjet head can be prevented, and ejection reliability can be improved. Compared with the colorless liquid application step in the present invention, since it is a process of spraying a small amount of moisture for adjusting humidity, the bleeding marks in the present invention cannot be eliminated. "Washing" refers to the process of removing dirt and impurities generated during the printing process, which is synonymous with the "laundering" described above. When sublimation dye ink is used as the ink, the processes of "steaming" and "washing" are required to fix it on the fabric. However, since the present invention is DTG printing using pigment ink, the processes of "steaming" and "washing" are unnecessary. Compared with the colorless liquid application step in the present invention, it is possible to remove the organic solvent and eliminate bleeding marks by washing after printing, but there are problems such as the generation of waste liquid and the need for drying and ironing as subsequent processes.

[0038] The colorless liquid application part is not particularly limited and can be appropriately selected according to the purpose. For example, an inkjet head, a sprayer (compressor), a hand spray, a steam generator, an immersion container, etc. can be mentioned. However, an inkjet head is preferable in terms of being easily incorporated into the same apparatus as the pretreatment liquid application part, the white ink application part, and the color ink application part.

[0039] The colorless liquid can contain water and can be appropriately selected according to the purpose as long as it is a colorless liquid that satisfies all of the following conditions (1) to (4). Pure water is preferable. (1) It does not change color due to adhesion to the image area or heat treatment. (2) The boiling point is below the heat treatment temperature. (3) It does not contaminate the colored fabric. (4) No precipitation of solids occurs. Examples of using a liquid other than pure water as the colorless liquid include, for example, an aqueous solution to which a fragrance component is added for the purpose of scenting or deodorizing, and an aqueous solution to which a medicinal component is added for the purpose of disinfection (sterilization, bactericidal action).

[0040] In the present invention, the area where the colorless liquid is applied is adjusted according to the timing of applying the colorless liquid. Examples of the timing of applying the colorless liquid include cases where the colorless liquid is applied after the color ink applying section applies the color ink, cases where the colorless liquid is applied in parallel with the application of the white ink by the white ink applying section and / or the application of the color ink by the color ink applying section, and cases where the colorless liquid is applied before the white ink applying section applies the white ink.

[0041] When the colorless liquid applying section applies the colorless liquid after the color ink applying section applies the color ink, the colorless liquid is applied to the "image forming area" and the "bleed mark area". Since the colorless liquid application step is performed last, the white ink and the color ink have already reacted with the pretreatment liquid and are aggregated so as to entangle the fabric fibers. Therefore, the ink layer in the image forming area is not damaged unless the colorless liquid is applied with such a force that physical pressure is generated. By applying the colorless liquid to the bleed mark area, not only the effect of eliminating the bleed marks can be obtained, but also by applying the colorless liquid to the image forming area, the effect of suppressing the stickiness caused by the solvent in the image forming area can be obtained.

[0042] When the colorless liquid applying section applies the colorless liquid in parallel with the application of the white ink by the white ink applying section and / or the application of the color ink by the color ink applying section, the colorless liquid is not applied to the "image forming area". Since the colorless liquid is applied before the pretreatment liquid and the ink react and aggregate, if the colorless liquid is applied to the image forming area, damages such as image peeling, bleeding, and melting will occur. By applying the colorless liquid to the bleed mark area, not only the effect of eliminating the bleed marks can be obtained, but also by applying the colorless liquid in parallel with the application of the white ink or the color ink, the effect of improving productivity can be obtained.

[0043] When the colorless liquid application unit applies a colorless liquid in parallel with the application of white ink by the white ink application unit and / or the application of color ink by the color ink application unit, a gap region where nothing is applied may be provided between the image formation region and the region where the colorless liquid is applied. By providing a gap region where nothing is applied, the effect of reliably avoiding damage to the image due to the mixing of ink and the colorless liquid can be further obtained.

[0044] When the colorless liquid application unit applies a colorless liquid in parallel with the application of white ink by the white ink application unit and / or the application of color ink by the color ink application unit, a gap region may be provided between the image formation region and the region where the colorless liquid is applied, and the amount of the colorless liquid applied decreases as it gets closer to the image formation region. The effect of further enhancing the effect of eliminating bleeding marks can be obtained while minimizing damage to the image due to the mixing of ink and water as much as possible, compared to the case where nothing is applied to the gap region.

[0045] When the colorless liquid application unit applies a colorless liquid before the white ink application unit applies white ink, the colorless liquid is applied not only to the "bleeding mark region" but also to the "pretreatment liquid application region". When the stock solution of the pretreatment liquid is difficult to penetrate the fabric, the pretreatment liquid can be evenly applied to the fabric by applying the colorless liquid to the pretreatment liquid application region for dilution. Not only can the effect of eliminating bleeding marks be obtained by applying the colorless liquid to the bleeding mark region, but also the pretreatment liquid can be evenly applied to the fabric that is difficult for the pretreatment liquid to penetrate by applying the colorless liquid to the pretreatment liquid application region to dilute the pretreatment liquid on the fabric, and the effect of improving the image quality and washing fastness can be obtained.

[0046] Before the white ink application unit applies white ink, if the colorless liquid application unit applies a colorless liquid and the pretreatment liquid application unit applies the pretreatment liquid not only to the image formation area but also to the overflow area, the colorless liquid is applied at least around the overflow area. Since the colorless liquid is applied before the ink, if the same amount of the colorless liquid as the measure against bleeding marks is applied to the pretreatment liquid application area including the overflow area, the pretreatment liquid will be diluted, which may cause insufficient color development of the ink. Note that if the colorless liquid is an amount for diluting the pretreatment liquid, the colorless liquid may be applied to the pretreatment liquid application area as well. By applying the colorless liquid at least around the overflow area, not only the effect of eliminating bleeding marks can be obtained, but also the effect of suppressing the influence of the displacement of the landing positions of the pretreatment liquid and the ink can be obtained by applying the pretreatment liquid to an area wider than the image formation area.

[0047] Before the white ink application unit applies white ink, if the colorless liquid application unit applies a colorless liquid and the pretreatment liquid application unit applies the pretreatment liquid not only to the image formation area but also to the overflow area, the colorless liquid may be applied not only around the overflow area but also to the overflow area. In that case, in the overflow area, the amount of the colorless liquid applied is reduced as it is closer to the image formation area, and the amount of the pretreatment liquid is increased. Comparing with the case where the colorless liquid is applied only around the overflow area, the effect of eliminating bleeding marks is improved by applying the colorless liquid to the overflow area as well.

[0048] When the amount of white ink applied by the white ink application unit is large, bleeding marks of the solvent occur significantly. Therefore, when the amount of white ink in the image formation area is large, a relatively large amount of the colorless liquid is applied to the bleeding mark area around it. Conversely, when the amount of white ink in the image formation area is small, a relatively small amount of the colorless liquid is applied to the bleeding mark area around it. By applying an appropriate amount of the colorless liquid, the colorless liquid is used efficiently (so as not to be wasted). Adjusting the amount of the colorless liquid to be applied is effective when printing on a colored fabric. When expressing the same color as the colored fabric, the color of the colored fabric itself may be utilized. Therefore, there may be cases where it is not necessary to apply a large amount of white ink. For example, a printing method is generally cited in which no white ink is applied at all to the area where black is expressed by utilizing the color of the black fabric itself in the image forming area, and a large amount of white ink is applied to the area where white is to be expressed in the image forming area.

[0049] (Heat treatment unit) After applying the colorless liquid, the heat treatment unit performs a heat treatment process to evaporate and remove unnecessary moisture and fix the ink on the colored fabric. The heat treatment unit may perform a heat and pressure treatment that combines heating and pressurization as the heat treatment.

[0050] The heat treatment unit is not particularly limited and can be appropriately selected according to the purpose. Examples include a heat press machine that combines heating and pressurization, a hot air drying and fixing machine that blows hot air, and a conveyor heater that conveys the material under a heat source by a conveyor.

[0051] Hereinafter, the present invention will be described in more detail with reference to the drawings.

[0052] FIG. 1 is a schematic diagram showing an example of a printing apparatus according to an embodiment of the present invention. The printing apparatus 1 includes a pretreatment liquid application unit 100, a white ink application unit 200, a color ink application unit 300, and a colorless liquid application unit 400.

[0053] FIG. 2 is a schematic diagram showing a configuration example of various discharge heads of a conventional printing apparatus incorporating a pretreatment liquid discharge head as the pretreatment liquid application unit. All of the examples shown in Types 1 to 4 of FIG. 2 have a pretreatment liquid discharge head 101, a white ink discharge head 201, and color ink discharge heads (yellow: 301Y, magenta: 301M, cyan: 301C, black: 301K). In the figure, the colored cloth fabric 10 is conveyed from top to bottom, and various heads are arranged such that first the pretreatment liquid, then the white ink, and finally the color ink (cyan, magenta, yellow, black) are discharged for printing.

[0054] Note that except for Type 3, the white ink discharge head 201 is arranged at the center of the carriage (a unit that mounts the heads together). However, in the case of bidirectional printing where the heads perform printing in both left and right scans, this is an arrangement for discharging the left and right color inks starting from the central white ink. Also, in FIG. 2, the types of color inks mounted are four colors: cyan, magenta, yellow, and black, but the order is not limited to the examples shown in Types 1 to 4, and photo inks such as light cyan, light magenta, and gray, or specialty inks such as RGB, orange, and violet may be mounted.

[0055] FIG. 3 is a diagram for explaining that by incorporating a pretreatment liquid application unit into the printing apparatus, the heat treatment process can be reduced. The flowchart on the left side of FIG. 3 shows the process (conventional method 1) when using a printing apparatus without an incorporated pretreatment liquid application unit. Since the pretreatment liquid application step S11, the white ink application step S13, and the color ink application step S14 are carried out in different apparatuses, it is necessary to perform a heat treatment step S12 in between. The reason is that in order to improve production efficiency, after performing up to the heat treatment step S12, a fabric stock for image printing waiting for the pretreatment liquid to dry was created as a make-ready. After the color ink application step S14, the heat treatment step S15 is performed again, and packaging S16 is carried out to complete the product.

[0056] On the other hand, the flowchart on the right side of FIG. 3 shows the process (conventional method 2) when using a printing apparatus incorporating a pretreatment liquid application unit. Since the pretreatment liquid application step S21, the white ink application step S22, and the color ink application step S23 can be interlocked as a series of steps, the intermediate heat treatment step can be omitted. After the color ink application step S23, a heat treatment step S24 is performed, and packaging S25 is carried out to complete the product. Compared with the case of using a printing apparatus not incorporating a pretreatment liquid application unit, since the number of heat treatment steps is small, it is a highly productive method. However, since the object to be printed is in a wet state from the pretreatment liquid application step S21 to the color ink application step S23, when a large amount of white ink is used as a base, there is a problem that bleeding marks caused by wet spread occur outside the printing area.

[0057] FIG. 4 is a diagram showing the relationship between the area to which the pretreatment liquid is applied and the area where the printed image is formed. The left side of FIG. 4 shows the pretreatment liquid application area when using a printing apparatus not incorporating a pretreatment liquid application unit (conventional method 1). Since the pretreatment liquid application step was performed by a separate apparatus from the white ink application step and the color ink application step, or was performed manually using a hand spray, brush, roller, etc., the image formation area 20 was often unclear at the stage of the pretreatment liquid application step. Therefore, the pretreatment liquid was applied over a wide area of the colored fabric so that the ink applied to the image formation area 20 came into contact with the pretreatment liquid. As a result, the pretreatment liquid application area 24 extends greatly outside the image formation area 20, and in some cases, bleeding marks caused by the pretreatment liquid, as in Patent Document 1, may occur due to unevenness when the pretreatment liquid is applied.

[0058] On the other hand, the right side of FIG. 4 shows the pretreatment liquid application area when using a printing apparatus incorporating a pretreatment liquid application unit (Conventional Method 2). Since the pretreatment liquid application step, the white ink application step, and the color ink application step are performed within the same apparatus, the pretreatment liquid application area 24 can be accurately discharged in accordance with the image formation area 20. As a result, when using a printing apparatus incorporating a pretreatment liquid application unit, in addition to reducing the amount of pretreatment liquid used, bleeding caused by the pretreatment liquid does not pose a problem. In FIG. 4, for the purpose of showing the pretreatment liquid application area 24, the position is shifted for display, but originally the pretreatment liquid is applied to the area that coincides with the image formation area 20.

[0059] FIG. 5 is a diagram showing that bleeding marks are generated by the application of white ink. FIG. 5 is a photograph after performing the following steps on regions A to C on a colored fabric substrate and then performing a heat treatment step using a heat press machine. A: Only the pretreatment liquid application step was performed. B: In addition to A, a white ink application step was further performed to form a base. C: In addition to B, a color ink application step was further performed to form a color image. In any of A to C, it can be confirmed as an area where the bleeding marks appear darker than the fabric color. Comparing the bleeding marks of A and B, it can be confirmed that the bleeding marks of B are wider and the influence of using a large amount of white ink is significant. On the other hand, there is almost no difference in the size of the bleeding marks between B and C, and it can be confirmed that the formation of a color image with color ink does not significantly affect bleeding.

[0060] FIG. 6 is a diagram showing how the process of forming bleeding marks is seen from the cross-section of a colored fabric substrate. In FIG. 6, an example using a heat press machine 501 as a heat treatment unit is shown. The upper part of Fig. 6 shows the formation process of bleeding marks in the prior art (Prior Art 1). Immediately after the color ink application step, the white ink 12 and the color ink 13, and the organic solvent 15 derived from the white ink are distributed on the colored fabric 10 as shown in the upper left of Fig. 6. Note that since it is an image diagram indicating the presence of the organic solvent, the organic solvent 15 indicated by the white circles in Fig. 6 does not show the shape of the organic solvent. The white ink 12 and the color ink 13 immediately after the color ink application step are undergoing an aggregation reaction by the pretreatment liquid, but they are only loosely coagulated on the colored fabric 10 until they are thermoset by the heat treatment step. The ink until it is thermoset can be easily peeled off if a physical force is applied, but it is not affected by the degree of moisture movement in the heat treatment step.

[0061] In the heat treatment step, by performing a heat and pressure treatment with the heat press machine 501, the ink is firmly fixed to the fabric by thermosetting. When using a heat press machine 501 that heats by contacting the heat source, in order to prevent the image formed by the white ink 13 and the color ink 14 from sticking to the heat source and peeling off, a non-permeable sheet 16 (such as a kitchen paper, a Teflon (registered trademark) sheet, etc.) is sandwiched in between, and a heat and pressure treatment is performed. Since the image side of the colored fabric 10 is sealed with the non-permeable sheet 16 and the opposite side is sealed on the receiving side of the heat press machine 501, the moisture evaporated by heating escapes in the plane direction of the colored fabric 10. At this time, the organic solvent 15 also moves inside the colored fabric 10 together with the moisture.

[0062] The temperature of the heat press machine 501 is set to a temperature that does not damage the colored fabric 10 (does not dissolve or thermally denature it) and can remove moisture. For example, when the colored fabric 10 is a polyester fabric, it is set to about 100 to 120°C. Although all the moisture evaporates by the heat and pressure treatment using the heat press machine 501, since the organic solvent 15 has a high boiling point (for example, glycerin is 290°C, propanediol is about 190°C), it remains in the colored fabric 10 as it is and also remains as the bleeding mark 17.

[0063] The lower side of Fig. 6 shows a mechanism capable of eliminating bleeding marks by applying a colorless liquid (Conventional Method 2). By using a heat press machine 501 for heat and pressure treatment, the organic solvent 15 diffuses onto the colored fabric 10 along with the evaporating moisture. By additionally applying a colorless liquid containing water, the concentration of the organic solvent 15 on the colored fabric 10 is reduced. Fig. 6 shows an example in which water is sprayed using a hand spray 402 as the colorless liquid application part. By applying water and performing heat and pressure treatment using the heat press machine 501, the organic solvent 15 diffuses widely on the colored fabric 10, and the concentration of the organic solvent 15 can be lowered to such an extent that it cannot be recognized as a bleeding mark.

[0064] A concern at this time is that the printed image may be damaged (faded, bleeding, flowing, scratched, etc.) by the application of water. Immediately after the white ink application step and the color ink application step, the ink is only loosely solidified on the colored fabric 10. If water is sprayed strongly or poured, the printed image will be damaged and the print quality will deteriorate. By spraying water on the surface of the printed image without contact or at an angle that deflects the impact, or by reducing the impact by making the spray droplets finer, water can be applied without damaging the printed image.

[0065] Fig. 7 is a diagram comparing the man-hours of a method for eliminating bleeding marks in a printing method according to the conventional method and a printing method according to the present invention. The flowchart on the left side of Fig. 7 shows a printing method according to the conventional method, and the bleeding marks are eliminated by performing washing S36. After that, drying S37 and ironing S38 are required as additional steps to make a product, so the total man-hours increase, and the problem is that the productivity is low.

[0066] On the other hand, the flowchart on the right side of Fig. 7 shows a printing method according to an embodiment of the present invention, and the bleeding marks are eliminated by performing a colorless liquid application step S44. Therefore, the steps of washing, drying, and ironing that were necessary in the conventional method are no longer required.

[0067] Figures 8 to 14 are diagrams showing the progress of the surface state of the colored fabric substrate, classified according to the timing of applying the colorless liquid in the present invention. In Figures 8 to 14, for the sake of easy understanding of the printing process, it is shown that the pretreatment and the ink are laminated on the colored fabric substrate, but originally they penetrate into the interior of the colored fabric substrate.

[0068] Figure 8 is a diagram showing the progress of the surface state of the colored fabric substrate 10 when the colorless liquid applying portion applies the colorless liquid 14 to the image forming region 20 and the bleeding trace region 21 in the case where the color ink applying portion applies the color ink 13 and then the colorless liquid applying portion applies the colorless liquid 14. The organic solvent 15 contained in the white ink 12 used in a large amount as the base bleeds out around the image forming region 20, but by applying the colorless liquid 14 containing water to the bleeding region 21, the organic solvent 15 diffuses on the colored fabric substrate 10 and the bleeding trace is eliminated. In addition, since the white ink 12 and the color ink 13 react with the pretreatment liquid 11 and aggregate so as to entangle the fabric fibers, the ink layer in the image forming region 20 is not damaged unless the colorless liquid 14 is applied to the image forming region 20 with such a force that physical pressure is generated. By applying the colorless liquid to the image forming region 20 as well, the stickiness caused by the solvent can be suppressed.

[0069] Figure 9 is a diagram showing the progress of the surface state of the colored fabric substrate 10 when the colorless liquid applying portion applies the colorless liquid 14 to the bleeding trace region 21 without applying the colorless liquid 14 to the image forming region 20 in the case where the white ink applying portion applies the white ink 12, the color ink applying portion applies the color ink 13, and the colorless liquid applying portion applies the colorless liquid 14 in parallel. Since the colorless liquid 14 is applied before the pretreatment liquid 11 reacts with the white ink 12 and the color ink 13, the colorless liquid 14 is not applied to the image forming region 20 so as not to damage the image. By applying one or more of the white ink 12 and the color ink 13 and the colorless liquid 14 in parallel, the productivity is improved. For example, in a printing method using an inkjet method, the number of printing layers can be reduced.

[0070] FIG. 10 is a diagram showing the progress of the state of the surface of the colored fabric 10 when the colorless liquid application unit applies the colorless liquid 14 to the bleed mark area 21 in parallel with the application of the white ink 12 by the white ink application unit and the application of the color ink 13 by the color ink application unit, and a gap area 22 where nothing is applied is provided between the image formation area 20 and the area where the colorless liquid is applied. By providing the gap area 22 where nothing is applied, an effect of reliably avoiding damage to the image due to mixing of the white ink 12, the color ink 13, and the colorless liquid 14 can be further obtained.

[0071] FIG. 11 is a diagram showing the progress of the state of the surface of the colored fabric 10 when the colorless liquid application unit applies the colorless liquid 14 to the bleed mark area 21 in parallel with the application of the white ink 12 by the white ink application unit and the application of the color ink 13 by the color ink application unit, and a gap area 22 where the amount of the colorless liquid 14 applied decreases as it gets closer to the image formation area 20 is provided between the image formation area 20 and the area where the colorless liquid is applied. An effect of further enhancing the effect of eliminating the bleed marks while minimizing damage to the image due to mixing of the white ink 12, the color ink 13, and the colorless liquid 14 can be obtained as compared with the case of FIG. 10.

[0072] FIG. 12 is a diagram showing the progress of the state of the surface of the colored fabric 10 when the colorless liquid application unit applies the colorless liquid 14 to the image formation area 20 and the bleed mark area 21 before the white ink application unit applies the white ink 12. FIG. 12 shows an example in which the pretreatment liquid application area is the same area as the image formation area 20. By applying the colorless liquid 14 also to the pretreatment liquid application area, the pretreatment liquid 11 can be diluted on the colored fabric 10. With this printing method, the pretreatment liquid can be evenly applied to the fabric on which the pretreatment liquid is difficult to penetrate, and an effect of improving the image quality and washing fastness can be obtained.

[0073] FIG. 13 is a diagram showing the progress of the state of the surface of the colored fabric 10 when the colorless liquid application unit applies the colorless liquid 14 around the overhang area 23, in the case where the pretreatment liquid application unit applies the pretreatment liquid 11 not only to the image forming area 20 but also to the overhang area 23 before the white ink application unit applies the white ink 12. Since the colorless liquid 14 is applied before the white ink 12 and the color ink 13 are applied, if the same amount of the colorless liquid as the countermeasure against bleeding marks is applied to the pretreatment liquid application area including the overhang area 23, the pretreatment liquid 11 will be diluted, which may cause insufficient ink color development. FIG. 13 shows a case where a small amount of the colorless liquid 14 that does not cause insufficient ink color development is applied to the pretreatment liquid application area to dilute the pretreatment liquid 11. By applying the pretreatment liquid 11 to a wider area than the image forming area 20 by the pretreatment liquid application unit, an effect of suppressing the influence of the landing position shift between the pretreatment liquid 11 and the white ink 12 or the color ink 13 can be obtained.

[0074] FIG. 14 is a diagram showing the progress of the state of the surface of the colored fabric 10 when the colorless liquid application unit applies the colorless liquid 14 not only around the overhang area 23 but also to the overhang area 23, in the case where the pretreatment liquid application unit applies the pretreatment liquid 11 not only to the image forming area 20 but also to the overhang area 23 before the white ink application unit applies the white ink 12. Since the colorless liquid 14 is applied before the white ink 12 and the color ink 13 are applied, if the same amount of the colorless liquid as the countermeasure against bleeding marks is applied to the pretreatment liquid application area including the overhang area 23, the pretreatment liquid 11 will be diluted, which may cause insufficient ink color development. FIG. 14 shows a case where a small amount of the colorless liquid 14 that does not cause insufficient ink color development is applied to the pretreatment liquid application area to dilute the pretreatment liquid 11. Compared with the case of FIG. 13, by applying the colorless liquid 14 to the overhang area 23 as well, the effect of eliminating bleeding marks is improved.

[0075] FIG. 15 is a view showing a region to which a colorless liquid is applied. The length of the width of the colorless liquid application region 25 is preferably at least twice the length of the width of the bleeding mark region 21. By being at least twice, the organic solvent diffuses onto the colored fabric 10 to such an extent that the bleeding marks cannot be recognized. Also, as the colorless liquid application region 25, as long as the printed image is not physically damaged, it may include the image forming region 20 or may be the entire surface of the colored fabric 10.

[0076] FIG. 16 is a conceptual diagram of dilution of a pretreatment liquid by ejection of a colorless liquid. The pretreatment liquid containing an aggregating component, a resin, and a solvent (glycerin) often has a higher viscosity than water and is difficult to spread by wetting. Therefore, on the fabric 18, the pretreatment liquid 11 is difficult to penetrate into the fabric 18, and the surface coating area becomes small. As shown on the right side of FIG. 16, when dots of the colorless liquid 14 and the pretreatment liquid 11 are ejected so as to overlap in the order of the colorless liquid 14 containing water and the pretreatment liquid 11, the pretreatment liquid 11 spreads widely through the water that has spread on the fabric 18 first, and the surface coating area can be increased.

[0077] FIG. 17 shows a cross-sectional view of a fabric when a pretreatment liquid is applied to a fabric with low absorbency. The undiluted pretreatment liquid with low permeability is difficult to spread on the fabric, and regions where the pretreatment liquid is not applied are generated. Since the aggregation due to the reaction between the pretreatment liquid and the ink does not proceed sufficiently, it becomes a factor in reducing the image quality and washing fastness. On the other hand, the diluted pretreatment liquid with improved permeability spreads easily on the fabric, and the pretreatment liquid can be uniformly applied on the fabric surface, improving the image quality and washing fastness. However, if the amount of the colorless liquid used for diluting the pretreatment liquid is large, the aggregating effect of the pretreatment liquid decreases, and the image quality and washing fastness decrease. Therefore, the amount of the colorless liquid used for diluting the pretreatment liquid is preferably three times or less the amount of the pretreatment liquid.

[0078] FIG. 18 shows a cross-sectional view of a highly absorbent fabric when a pretreatment liquid is applied thereto. In the case of a highly absorbent fabric, if the pretreatment liquid is diluted, the pretreatment liquid will be absorbed too much by the fabric, and the components of the pretreatment liquid will not remain sufficiently on the fabric surface. In this case, the aggregation due to the reaction between the pretreatment liquid and the ink does not proceed sufficiently, which causes deterioration of the image quality and washing fastness. Therefore, when printing on a highly absorbent fabric, it is preferable not to dilute the pretreatment liquid with a colorless liquid.

[0079] FIGS. 19 and 20 are diagrams showing an example of the printing apparatus of the present invention using an inkjet method. FIG. 19 is a perspective view of the printing apparatus, and FIG. 20 is a top view of the printing apparatus. The printing apparatus 1 includes a stage 50, a carriage 51, a cartridge 52, and an operation panel 53. FIGS. 19 and 20 show a printing apparatus having a double carriage configuration in which two carriages 51 are mounted as an example, but the number of carriages may be one or three or more.

[0080] The stage 50 is a plate-like member that supports the medium on its upper surface. The stage 50 is vertically movable and is supported by the housing of the printing apparatus 1 so as to be slidable in the sub-scanning direction (front-rear direction) orthogonal to the vertical direction and the main scanning direction (left-right direction).

[0081] The carriage 51 is disposed above the stage 50. The carriage 51 supports, on its lower surface, discharge nozzles that discharge the pretreatment liquid, white ink, color ink, and colorless liquid accommodated in the cartridge 52 via supply tubes. Further, the carriage 51 is supported by the housing of the printing apparatus 1 so as to be reciprocally movable in the main scanning direction (left-right direction) orthogonal to the vertical direction and the sub-scanning direction (front-rear direction). Then, in the process of the carriage 51 reciprocating in the main scanning direction, the pretreatment liquid, white ink, color ink, and colorless liquid are discharged from the discharge nozzles at a predetermined timing, thereby forming an image on the medium supported by the stage 50 located below the discharge nozzles.

[0082] The operation panel 53 includes an operation unit that receives input operations from the user and a display that notifies the user of information. The operation unit includes, for example, hard keys, a touch panel superimposed on the display, and the like. Then, the operation panel 53 acquires information from the user through the operation unit and provides information to the user through the display.

[0083] Figs. 21 to 27 are diagrams showing examples of the carriage configurations of the printing apparatus of the present invention using an inkjet method.

[0084] Fig. 21 is a diagram showing an example of a single carriage configuration in which a pretreatment liquid discharge nozzle 101, a white ink discharge nozzle 201, a color ink discharge nozzle 301, and a colorless liquid discharge nozzle 401 are mounted on one carriage 51. By arranging the pretreatment liquid discharge nozzle 101, the white ink discharge nozzle 201, the color ink discharge nozzle 301, and the colorless liquid discharge nozzle 401 in this order with respect to the media conveyance direction, printing can be completed with only one-way conveyance, so there is an advantage of high productivity.

[0085] Figs. 22 and 23 are diagrams showing examples of a double carriage configuration having two carriages. Fig. 22 is a diagram showing a carriage configuration in which the pretreatment liquid discharge nozzle 101 and the colorless liquid discharge nozzle 401 are mounted on the first carriage 51A, and the white ink discharge nozzle 201 and the color ink discharge nozzle 301 are mounted on the second carriage 51B. Since the colorless liquid discharge nozzle 401 is mounted on the same carriage as the pretreatment liquid discharge nozzle 101, the pretreatment liquid application step and the colorless liquid application step can be performed in parallel. FIG. 23 is a diagram showing a carriage configuration in which the pretreatment liquid discharge nozzle 101 is mounted on the first carriage 51A, and the white ink discharge nozzle 201, the color ink discharge nozzle 301, and the colorless liquid discharge nozzle 401 are mounted on the second carriage 51B. Since the colorless liquid discharge nozzle 401 is mounted on the same carriage as the white ink discharge nozzle 201 and the color ink discharge nozzle 301, one or more of the white ink application step and the color ink application step can be performed in parallel with the colorless liquid application step.

[0086] FIGS. 24 to 26 are diagrams showing examples of a triple carriage configuration having three carriages. FIG. 24 is a diagram showing a carriage configuration in which the pretreatment liquid discharge nozzle 101 is mounted on the first carriage 51A, the white ink discharge nozzle 201 and the color ink discharge nozzle 301 are mounted on the second carriage 51B, and the colorless liquid discharge nozzle 401 is mounted on the third carriage 51C. Since the white ink discharge nozzle 201 and the color ink discharge nozzle 301 are mounted on the same carriage, it is necessary to convey the medium in the reverse direction after discharging the white ink and then discharge the color ink. FIG. 25 is a diagram showing a carriage configuration in which the pretreatment liquid discharge nozzle 101 is mounted on the first carriage 51A, the white ink discharge nozzle 201 and the colorless liquid discharge nozzle 401 are mounted on the second carriage 51B, and the color ink discharge nozzle 301 and the colorless liquid discharge nozzle 401 are mounted on the third carriage 51C. Since the colorless liquid discharge nozzle 401 is mounted on the same carriage as the white ink discharge nozzle 201 and the color ink discharge nozzle 301, one or more of the white ink application step and the color ink application step can be performed in parallel with the colorless liquid application step. FIG. 26 is a diagram showing a carriage configuration in which a pretreatment liquid discharge nozzle 101 and a colorless liquid discharge nozzle 401 are mounted on a first carriage 51A, a white ink discharge nozzle 201 is mounted on a second carriage 51B, and a color ink discharge nozzle 301 and a colorless liquid discharge nozzle 401 are mounted on a third carriage 51C. Since the colorless liquid discharge nozzle 401 is mounted on the same carriage as the pretreatment liquid discharge nozzle 101, the pretreatment liquid application step and the colorless liquid application step can be performed in parallel. Further, since the colorless liquid discharge nozzle 401 is mounted on the same carriage as the color ink discharge nozzle 301, the color ink application step and the colorless liquid application step can be performed in parallel.

[0087] FIG. 27 is a diagram showing an example of a four-carriage configuration in which a pretreatment liquid discharge nozzle 101 is mounted on a first carriage 51A, a white ink discharge nozzle 201 is mounted on a second carriage 51B, a color ink discharge nozzle 301 is mounted on a third carriage 51C, and a colorless liquid discharge nozzle 401 is mounted on a fourth carriage 51D. Similar to the case of the single carriage configuration, there is an advantage of high productivity because it is not necessary to convey the medium in the reverse direction.

[0088] When the colorless liquid discharge nozzle 401 is mounted on the same carriage as the pretreatment liquid discharge nozzle 101, the white ink discharge nozzle 201, the color ink discharge nozzle 301, etc., it is not always necessary to perform the pretreatment liquid application step, the white ink application step, the color ink application step, etc. in parallel with the colorless liquid application step, and the user can freely select according to the purpose. For example, in the carriage configuration shown in FIG. 26, a printing method may be used in which the colorless liquid application step and the pretreatment liquid application step are performed in parallel, and the color ink application step and the colorless liquid application step are not performed in parallel, or a printing method may be used in which the colorless liquid application step and the pretreatment liquid application step are not performed in parallel, and the color ink application step and the colorless liquid application step are performed in parallel.

[0089] The advantages of double carriage and triple carriage configurations over a quattro carriage include the ability to reduce the size of the printing device due to the smaller number of carriages. Another advantage of double carriage and triple carriage configurations over a single carriage is the improved reliability when discharging liquid from the nozzles. For example, when discharging the pretreatment liquid, white ink and color ink are not discharged, that is, the state becomes easy to dry. Therefore, nozzle clogging due to ink sticking is likely to occur in a single carriage configuration.

[0090] (Configuration of the control block) Next, the configuration of the control block included in the printing device according to the present embodiment will be described with reference to FIG. 28. FIG. 28 is a diagram showing an example of the configuration of the control block of the printing device according to an embodiment of the present invention. As shown in FIG. 28, a controller 110 as a control block of the printing device includes a CPU 111, a ROM 112, a RAM 113, an NVRAM 114, and an ASIC 115.

[0091] The CPU 111 is connected to an operation panel 150 as a display operation unit for inputting and displaying information necessary for the printing device, and controls the operations of the respective functional components of the printing device. Further, the CPU 111 also has a function of controlling the conveyance operation of the platen 140 (movement in the sub-scanning direction) and the movement operation of the carriage 121 in the main scanning direction, and the liquid discharge operations by various liquid discharge heads (pretreatment liquid discharge head 120a, white ink discharge head 120b, color ink discharge head 120c, colorless liquid discharge head 120d).

[0092] The ROM 112 is a non-volatile storage medium that stores programs executed by the CPU 111 and other fixed data. By executing the programs stored in the ROM 112 by the arithmetic processing function of the CPU 111, the controller 110 described later is configured.

[0093] The RAM 113 temporarily stores image data and the like used for image formation processing. Also, the RAM 113 functions as a work area when the program control unit is executed.

[0094] The NVRAM 114 is a rewritable non-volatile storage medium for retaining data even while the power of the printing apparatus is turned off.

[0095] The ASIC 115 performs various signal processes on image data, such as image processing for rearrangement and the like, and processes input / output signals for controlling the entire apparatus.

[0096] Also, the controller 110 includes a host interface (I / F) 170, a discharge control unit 117, a main scanning motor drive unit 118, a sub-scanning motor drive unit 171, and an input / output (I / O) unit 116.

[0097] The host I / F 170 is responsible for transmitting and receiving data and control signals with the host side, such as the printer driver 501 of the external device 500.

[0098] The discharge control unit 117 generates drive waveforms for driving various liquid discharge heads (pretreatment liquid discharge head 120a, white ink discharge head 120b, color ink discharge head 120c, colorless liquid discharge head 120d), and outputs image data and various accompanying data for selectively driving the pressure generating means of the various liquid discharge heads to the head driver 1171.

[0099] The discharge control unit 117 adjusts the area to which the colorless liquid is applied and also changes the amount of the colorless liquid.

[0100] The main scanning motor drive unit 118 drives the main scanning motor 122.

[0101] The sub-scanning motor drive unit 171 is responsible for driving a sub-scanning motor that moves the platen 140 in the sub-scanning direction.

[0102] The I / O unit 116 inputs detection signals from various sensors required for the operation of the printing apparatus.

[0103] Also, the controller 110 receives an image formation instruction related to image formation processing from the printer driver 501 provided in the external device 500 via a cable or network at the host I / F 170. The image formation instruction is generated by the printer driver 501 of an external device 500 having a host function such as an information processing device like a personal computer (PC), an image reading device like an image scanner, or an imaging device like a digital camera.

[0104] The controller 110 that has received the image formation instruction reads and analyzes the image formation instruction in the reception buffer included in the host I / F 170 by the CPU 111. Also, according to the analysis result, necessary image processing, data rearrangement processing, etc. are performed by the ASIC 115 and transferred to the ejection control unit 117. Therefore, the ejection control unit 117 outputs image data and a drive waveform to the head driver 1171 at a required timing. Note that the generation of dot pattern data for image output may be performed by storing font data in the ROM 112, for example, or the image data may be expanded into bitmap data by the printer driver 501 on the host side and transferred to the apparatus. Here, it is assumed to be performed by the printer driver 501, for example. According to the above, the image formation instruction corresponds to ejection instruction information.

[0105] The drive waveform generation unit of the ejection control unit 117 is composed of a D / A converter and an amplifier, etc. that perform D / A conversion on the pattern data of drive pulses stored in the ROM 112 and read by the CPU 111. Then, a drive waveform composed of one drive pulse or a plurality of drive pulses is output to the head driver 1171. The head driver 1171 drives various liquid ejection heads based on the image data (dot pattern data) corresponding to one line of the liquid ejection head 120 input serially. For this purpose, the head driver 1171 selectively applies the drive pulses constituting the drive waveform given from the drive waveform generation unit of the ejection control unit 117 to the pressure generation means of various liquid ejection heads.

[0106] Note that the head driver 1171 includes, for example, a shift register that inputs serial data such as a clock signal and image data, and a latch circuit that latches the register value of the shift register with a latch signal. In addition, it includes a level conversion circuit (level shifter) that changes the level of the output value of the latch circuit, an analog switch array (switch means) that is turned on / off by this level shifter, and the like. Functionally, an example is a case where required drive pulses included in a drive waveform are selectively applied to pressure generating means of various liquid ejection heads by controlling on / off of the analog switch array.

[0107] The image formation instruction (operation instruction information) includes information indicating the type of the object to be printed. The printing apparatus according to the present embodiment has a function of selecting and setting the amount of various liquids to be ejected according to the type of the object to be printed installed on the platen 140.

[0108] Note that aspects of the embodiments of the present invention are as follows, for example. <1> A pretreatment liquid applying unit that applies a pretreatment liquid to a predetermined area on a permeable object to be printed, A white ink applying unit that applies white ink to a predetermined area on the area where the pretreatment liquid has been applied to form a base with the white ink, A color ink applying unit that applies color ink to a predetermined area on the base with the white ink to form a color image, It has a colorless liquid applying unit that applies a colorless liquid containing water to a predetermined area including at least a part of the bleeding mark area around the image formation area, A printing apparatus characterized by adjusting an area to which the colorless liquid is applied according to the timing of applying the colorless liquid. <2> After the color ink applying unit applies the color ink, the colorless liquid applying unit applies the colorless liquid, The printing apparatus according to <1>, wherein the colorless liquid is applied to the image formation area and the bleeding mark area. <3> While the white ink is being applied by the white ink application unit and / or the color ink is being applied by the color ink application unit, the colorless liquid application unit applies the colorless liquid in parallel, The printing apparatus according to <1>, wherein the colorless liquid is not applied to the image forming area. <4> Before the white ink application unit applies the white ink, the colorless liquid application unit applies the colorless liquid, The printing apparatus according to <1>, wherein the colorless liquid is applied not only to at least a part of the bleeding trace area but also to a predetermined area on the pretreatment liquid application area. <5> The printing apparatus according to any one of <1> to <4>, wherein the amount of the colorless liquid applied by the colorless liquid application unit is reduced in a region where the amount of the white ink applied by the white ink application unit is small. <6> The printing apparatus according to any one of <1> to <5>, further comprising a heat treatment unit that performs heat treatment after forming an image. <7> A pretreatment liquid application step of applying a pretreatment liquid to a predetermined area on a permeable printing material, A white ink application step of applying white ink to a predetermined area on the area where the pretreatment liquid has been applied to form a base with the white ink, A color ink application step of applying color ink to a predetermined area on the base formed by the white ink to form a color image, A colorless liquid application step of applying a colorless liquid containing water to a predetermined area including at least a part of the bleeding trace area around the image forming area, A printing method characterized by adjusting the area to which the colorless liquid is applied according to the timing of applying the colorless liquid. <8> The printing method according to <7>, wherein the amount of the colorless liquid applied in the colorless liquid application step is reduced in a region where the amount of the white ink applied in the white ink application step is small. <9> The printing method according to any one of <7> to <8>, further comprising a heat treatment step of performing heat treatment after forming an image.

Explanation of Symbols

[0109] 1 Printing device 11 Pretreatment liquid 12 White ink 13 Color ink 14 Colorless liquid 17 Bleed mark 20 Image formation area 21 Bleed mark area 22 Gap area 100 Pretreatment liquid application part 200 White ink application part 300 Color ink application part 400 Colorless liquid application part

Prior Art Documents

Patent Documents

[0110]

Patent Document 1

Claims

1. A pretreatment liquid applying unit that applies a pretreatment liquid to a predetermined area on a permeable object to be printed, A white ink applying unit that applies white ink to a predetermined area on the area where the pretreatment liquid has been applied to form a base with the white ink, A color ink applying unit that applies color ink to a predetermined area on the base formed by the white ink to form a color image, It has a colorless liquid applying unit that applies a colorless liquid containing water to a predetermined area including at least a part of the bleeding mark area around the image forming area, A printing apparatus characterized by adjusting the area to which the colorless liquid is applied according to the timing of applying the colorless liquid.

2. After the color ink applying unit applies the color ink, the colorless liquid applying unit applies the colorless liquid, The printing apparatus according to claim 1, wherein the colorless liquid is applied to the image forming area and the bleeding mark area.

3. The colorless liquid applying unit applies the colorless liquid in parallel with the application of the white ink by the white ink applying unit and / or the application of the color ink by the color ink applying unit, The printing apparatus according to claim 1, wherein the colorless liquid is not applied to the image forming area.

4. Before the white ink applying unit applies the white ink, the colorless liquid applying unit applies the colorless liquid, The printing apparatus according to claim 1, wherein the colorless liquid is applied not only to at least a part of the bleeding mark area but also to a predetermined area on the pretreatment liquid applying area.

5. The printing apparatus according to any one of claims 1 to 4, characterized in that the amount of the colorless liquid applied by the colorless liquid applying unit is reduced in a region where the amount of the white ink applied by the white ink applying unit is small.

6. The printing apparatus according to any one of claims 1 to 4, further comprising a heat treatment unit that performs heat treatment after forming an image.

7. A pretreatment liquid applying step of applying a pretreatment liquid to a predetermined area on a permeable object to be printed, A white ink applying step of applying white ink to a predetermined area on the area where the pretreatment liquid has been applied to form a base with the white ink, A color ink applying step of applying color ink to a predetermined area on the base formed by the white ink to form a color image, Including a colorless liquid applying step of applying a colorless liquid containing water to a predetermined area including at least a part of the bleeding mark area around the image forming area, A printing method characterized by adjusting a region to which the colorless liquid is applied according to the timing of applying the colorless liquid. **Claim 8** The printing method according to claim 7, wherein the amount of the colorless liquid applied in the colorless liquid application step is reduced in a region where the amount of the white ink applied in the white ink application step is small. **Claim 9** The printing method according to claim 7, comprising a heat treatment step of performing heat treatment after forming an image.

Images