Manufacturing device of three-dimentional object and manufacturing method of three-dimentional object

Abstract

To provide a manufacturing device of a three-dimensional object which enables reduction of the size of the entire device and costs, and to provide a manufacturing method of the three-dimensional object.SOLUTION: A manufacturing device 100 of a three-dimensional object according to the disclose includes: a primer ink discharge head 101 which discharges a primer ink; a first radiation device 121; a discharge head unit 110 including a first coloring ink discharge head 111 configured to discharge a first coloring ink, and a second coloring ink discharge head 112 configured to discharge a second coloring ink; a second radiation device 122; and a transport device 105 (105a, 105b, 105c) which transports a three-dimensional object 1 through the components in a written order.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an apparatus for manufacturing a three-dimensional object and a method for manufacturing a three-dimensional object. [Background technology]

[0002] There is a growing trend to conserve resources, and there is a demand to reduce single-use plastics. Labels on containers such as PET bottles are discarded after their intended use is completed, and plastic labels in particular are difficult to recycle, leading to a very high disposal rate. In order to achieve a label-less society, a technology has been proposed for directly printing on containers (see, for example, Patent Document 1). Patent Document 1 discloses a device that prints directly on the side of a container, and discloses a print head that operates according to the drop-on-demand principle as the print head.

[0003] Also disclosed is a printing device that prints ultraviolet-curable inks, including cyan ink (C), magenta ink (M), black ink (K), and yellow ink (Y) (see, for example, Patent Document 2). Patent Document 2 describes a printing device technology that uses a letterpress printing method, but in the printing device shown in Figure 1 of Patent Document 2, printing units for each ink and ultraviolet ray irradiation units that cure each ink are alternately arranged around a transport drum. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Pat. No. 1,123,592 [Patent Document 2] International Publication No. 2010 / 150780 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 discloses an apparatus having only one printer head. However, in order to meet the demand for high aesthetics, a printing apparatus having multiple printer heads corresponding to multiple color inks is required for direct printing on containers. In general, when printing multiple color inks, ultraviolet irradiation has been performed after each color printing, as in the printing apparatus disclosed in Patent Document 2, in order to suppress bleeding between the color inks and obtain a highly detailed design. However, when directly printing on the side of a container as in Patent Document 1, if ultraviolet irradiation is performed for all colors of color ink as in the apparatus of Patent Document 2, a total of eight or more apparatuses, including four or more inkjet heads (C, M, Y, K) and four or more UV lamps, must be arranged per printing surface, and a certain distance must be secured between the inkjet heads and the UV lamps to prevent stray light from the UV lamps, which causes problems such as the complexity of the printing apparatus, the enlargement of the size of the printing apparatus, and the increase in cost.

[0006] An object of the present disclosure is to provide a three-dimensional object manufacturing apparatus and a three-dimensional object manufacturing method that can reduce the size of the entire apparatus and reduce costs. [Means for solving the problem]

[0007] The present invention provides an apparatus for manufacturing a three-dimensional object, which forms a printed portion on the outer surface of a three-dimensional object, the printed portion having a primer layer and an ink layer provided on the primer layer, the primer layer comprising a cured product of a primer ink, which is an active energy ray curable inkjet ink, the ink layer comprising a color portion comprising a cured product of a color ink, which is an active energy ray curable inkjet ink containing a coloring material, the color ink comprising at least a first color ink and a second color ink of a different color than the first color ink, the apparatus for manufacturing a three-dimensional object comprising: a primer ink ejection head that ejects the primer ink; a first irradiation device; an ejection head unit including a first color ink ejection head that ejects the first color ink and a second color ink ejection head that ejects the second color ink; a second irradiation device; and a transport device that transports the three-dimensional object in this order.

[0008] The three-dimensional object manufacturing apparatus according to the present invention encompasses a configuration further including a third irradiation device disposed downstream of the transport device with respect to the second irradiation device.

[0009] In the apparatus for producing a three-dimensional object according to the present invention, the ink layer further includes a background printing section between the primer layer and the coloring section, and the background printing section includes a cured product of a background white ink, which is an active energy ray curable inkjet ink containing a white coloring material, and the apparatus for producing a three-dimensional object further includes a background printing section forming unit between the first irradiation device and the ejection head unit, and the background printing section forming unit preferably includes a background white ink ejection head for ejecting the background white ink, and a fourth irradiation device, in that order. By curing the background white ink prior to the ink of the coloring section, the color ink can be fixed more stably on the background printing section. As a result, a clearer image can be obtained.

[0010] In the three-dimensional object manufacturing apparatus according to the present invention, it is preferable that the transport distance of the transport device between the primer ink ejection head and the first irradiation device is longer than the transport distance of the transport device between the ejection head unit and the second irradiation device. The primer layer obtained by leveling the primer ink can be made flat, while the bleeding of the color inks can be suppressed, thereby obtaining a clearer image.

[0011] The method for manufacturing a three-dimensional object according to the present invention includes forming a printed portion having a primer layer and an ink layer provided on the primer layer on the outer surface of the three-dimensional object, the primer layer including a cured product of a primer ink, which is an active energy ray curable inkjet ink, the ink layer including a color portion including a cured product of a color ink, which is an active energy ray curable inkjet ink containing a coloring material, the color ink including at least a first color ink and a second color ink having a different color from the first color ink, and the method for manufacturing a three-dimensional object includes a color ink applying step including at least a first color ink applying step of applying the first color ink onto the cured product of the primer ink and a second color ink applying step of applying the second color ink onto the cured product of the primer ink, and a second irradiation step of irradiating with active energy rays a color ink group including the first color ink and the second color ink that have been applied onto the cured product of the primer ink in the color ink applying step.

[0012] The method for manufacturing a three-dimensional object according to the present invention includes an embodiment that further includes, prior to the color ink application step, a primer ink application step of applying the primer ink to the outer surface of the three-dimensional object, and a first irradiation step of irradiating the primer ink applied to the outer surface of the three-dimensional object with active energy rays.

[0013] The method for producing a three-dimensional object according to the present invention encompasses an embodiment further comprising a third irradiation step of further irradiating the color inks with active energy rays after the second irradiation step.

[0014] In the method for producing a three-dimensional object according to the present invention, the ink layer further includes a background printed portion between the primer layer and the cured product of the color ink, and the background printed portion includes a cured product of a background white ink, which is an active energy ray curable inkjet ink containing a white coloring material. The method for producing a three-dimensional object further includes a background printed portion forming step between the first irradiation step and the color ink applying step, and the background printed portion forming step preferably includes a background white ink applying step of applying the background white ink onto the primer layer, and a fourth irradiation step of irradiating the background white ink applied onto the primer layer with active energy rays. By curing the background white ink prior to the ink of the color portion, the color ink can be more stably fixed onto the background printed portion. As a result, a clearer image can be obtained.

[0015] In the method for manufacturing a three-dimensional object according to the present invention, the time from the end of the primer ink application step to the start of irradiation of the active energy rays in the first irradiation step is preferably longer than the time from the end of the color ink application step to the start of irradiation of the active energy rays in the second irradiation step. The primer layer obtained by leveling the primer ink can be made flat, while bleeding of the color inks is suppressed, thereby obtaining a clearer image. Effect of the Invention

[0016] According to the present disclosure, it is possible to provide a three-dimensional object manufacturing apparatus and a three-dimensional object manufacturing method that can reduce the size of the entire apparatus and reduce costs. [Brief description of the drawings]

[0017] [Figure 1] 1 is an image showing an example of a three-dimensional object. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing an example of a printing unit. [Diagram 3] FIG. 4 is a schematic cross-sectional view showing another example of a printing unit. [Figure 4] 1 is a schematic configuration diagram showing an example of a three-dimensional object manufacturing apparatus according to an embodiment of the present invention; [Diagram 5] FIG. 4 is a schematic configuration diagram showing another example of the three-dimensional object manufacturing apparatus according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] The embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these descriptions. Various modifications of the embodiments may be made as long as the effects of the present invention are achieved.

[0019] The three-dimensional object manufacturing apparatus of this embodiment is an apparatus for forming a printing section 20 having a primer layer 21 and an ink layer 22 provided on the primer layer 21, as shown in FIG. 2 or FIG. 3, on the outer surface of a three-dimensional object 1 as shown in FIG. 1, for example.

[0020] (3D object) FIG. 1 is an image showing an example of a three-dimensional object. In FIG. 1, the three-dimensional object 1 is shown as a plastic container having a container body 10 having a mouth portion 11 and a body portion 12 connected to the mouth portion 11 as an example, but the present invention is not limited to this. The material of the three-dimensional object 1 is not particularly limited, and is, for example, plastic, glass, quartz, or metal. The three-dimensional object 1 may be a beverage container. The beverage container is, for example, a plastic container, a metal can, or a glass bottle as shown in FIG. 1. Of these, it is preferable that the three-dimensional object 1 is a plastic container.

[0021] As an example of the material of the three-dimensional object 1, the type of plastic is not particularly limited, but examples thereof include polyethylene terephthalate resin (PET), polybutylene terephthalate resin, polyethylene naphthalate resin, polyethylene resin, polypropylene resin (PP), cycloolefin copolymer resin (COC, cyclic olefin copolymer), ionomer resin, poly-4-methylpentene-1 resin, polymethyl methacrylate resin, polystyrene resin, ethylene-vinyl alcohol copolymer resin, acrylonitrile resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyamide resin, polyamideimide resin, polyacetal resin, polycarbonate resin, polysulfone resin, or tetrafluoroethylene resin, acrylonitrile-styrene resin, and acrylonitrile-butadiene-styrene resin. Among these, PET is particularly preferred. When the three-dimensional object 1 is a plastic container, the capacity of the plastic container is not particularly limited, and is, for example, 100 ml to 3000 ml.

[0022] The method for molding the plastic container is not particularly limited, but may be, for example, a blow molding method. Specifically, first, a preform is manufactured by injection molding a thermoplastic resin, and then the preform is blow molded to manufacture a plastic container having a shape in which a mouth part 11 and a body part 12 are connected in order as shown in FIG.

[0023] The container body 10 has an internal space for accommodating contents. The contents are not particularly limited, but may be, for example, liquids such as beverages, alcoholic beverages, and seasonings, foods, medicines, or industrial products. The beverages may be, for example, white beverages such as milk, yogurt beverages, lactic acid bacteria beverages, milk beverages, and alcoholic beverages, colored and transparent beverages such as straight tea, lemon tea, green tea, fruit juice beverages, carbonated beverages, and beer, cloudy beverages such as milk tea and coffee, or transparent beverages such as sports drinks, water, carbonated water, and chuhai.

[0024] The mouth 11 is a filling port and a pouring port for the contents. A cap (not shown) is attached to the mouth 11 to seal the bottle. A neck support ring may be formed at the lower end of the mouth 11.

[0025] The body 12 is a portion connected to the lower end of the mouth 11, and may have, in order from the mouth 11 side, an upper body 12a whose diameter increases from the lower end of the mouth 11 downward, a cylindrical body main body 12b, and a lower body 12c that is connected to the body main body 12b and has a ground surface with approximately the same diameter as the body main body 12b. The upper body 12a is sometimes called a shoulder due to its shape. The body main body 12b is, for example, cylindrical or regular n-sided cylindrical (where n is an integer of 4 or more). The lower body 12c becomes the bottom of the container body 10.

[0026] The printed section 20 is provided on at least one part of the upper body 12a, the body main body 12b, and the lower body 12c. In FIG. 1, an example is shown in which an identification code section showing a one-dimensional code is provided on the body main body 12b as the printed section 20, but the present invention is not limited to this. When the body 12 has ribs, it is preferable to provide the identification code section in a portion that avoids the ribs. The printed section 20 may include a character string (not shown) or a design image section (not shown) in addition to the identification code section. The character string includes product information such as the product name, raw material name, content amount, expiration date, and manufacturer. The design image section includes, for example, a logo showing the product name or company name, or an image for enhancing design such as a color, a painting, a photograph, an illustration, or a pattern.

[0027] The region where the printed part 20 is provided may be only one or two or more. The printed part 20 is preferably provided in a light-transmitting part of the body 12. The light-transmitting form includes, for example, achromatic and colorless transparent having a visible light transmittance to the extent that the other side of the body 12 can be seen through, chromatic and colorless transparent having a visible light transmittance to the extent that the other side of the body 12 can be seen through, semi-transparent having a visible light transmittance to the extent that the characters on the other side of the body 12 can be read by the light transmitted through the body 12, or opaque having a visible light transmittance to the extent that the characters on the other side of the body 12 cannot be read by the light transmitted through the body 12 but the silhouette can be seen. The container in which at least a part of the body 12 is light-transmitting includes, but is not limited to, a general PET bottle in which the entire body 12 is colorless and transparent, and a foamed PET bottle in which at least a part of the body 12 is semi-transparent or opaque having a visible light transmittance.

[0028] 2 is a schematic cross-sectional view showing an example of the printed part 20. As shown in FIG. 2, the printed part 20 has a primer layer 21 and an ink layer 22 in this order from the outer surface side of the body part 12.

[0029] The primer layer 21 is a layer for ensuring adhesion between the outer surface of the three-dimensional object 1 and the ink of the printed portion 20. The primer layer 21 may or may not have alkali releasability. In the present embodiment, the primer layer 21 preferably has alkali releasability. For example, in a recycling system, containers such as PET bottles are crushed and pulverized, and then sorted into crushed containers having a high specific gravity and crushed lids having a low specific gravity by a specific gravity separation method. This sorting is performed, for example, by immersing the container in a treatment liquid (for example, an alkaline aqueous solution). The primer layer 21 having alkali releasability can be made into a container with excellent recyclability. In this specification, alkali releasability refers to a property in which the primer layer 21 peels off from the body portion 12 when immersed in an alkaline solution. The alkali releasability may be, for example, that the primer layer 21 dissolves in an alkali and peels off from the body portion 12, or that the primer layer 21 does not dissolve in an alkali and peels off at the interface between the body portion 12 and the primer layer 21 in the alkaline solution. In this embodiment, the primer layer 21 is preferably such that, for example, when a region of the three-dimensional object 1 including at least the printed portion 20 is immersed and stirred in a 1.5 mass % sodium hydroxide aqueous solution at 85° C. to 90° C. for 15 minutes, at least a portion of the printed portion 20 peels off from the outer surface of the three-dimensional object 1. The thickness of the primer layer is not particularly limited, but is preferably 6 to 26 μm, and more preferably 11 to 15 μm.

[0030] The primer layer 21 is a coating film of a primer ink, which is an active energy ray-curable inkjet ink, and contains a cured primer material, which is a cured product of the primer ink. The primer layer 21 may consist of only the cured primer material, or may contain additives such as a filler or a colorant, such as a pigment or dye, in addition to the cured primer material.

[0031] The active energy ray curable inkjet ink preferably contains, for example, a polymerizable monomer and a polymerizable surfactant. From the viewpoint of alkali peelability, the polymerizable monomer preferably contains at least a polyfunctional monomer. The polyfunctional monomer is not particularly limited as long as it is a monomer having two or more polymerizable groups. From the viewpoint of curability, the polyfunctional monomer is preferably a polyfunctional radical polymerizable monomer, more preferably a polyfunctional ethylenically unsaturated monomer, for example, 3-methyl-1,5-pentanediol di(meth)acrylate, triethylene glycol di(meth)acrylate, 1,10-decanediol di(meth)acrylate. The polymerizable monomer may further contain a monofunctional monomer in addition to the polyfunctional monomer. The monofunctional monomer is not particularly limited as long as it is a monomer having one polymerizable group. From the viewpoint of curability, the monofunctional monomer is preferably a monofunctional radical polymerizable monomer, more preferably a monofunctional ethylenically unsaturated monomer. Examples of the monofunctional ethylenically unsaturated monomer include monofunctional (meth)acrylate, monofunctional (meth)acrylamide, monofunctional aromatic vinyl compound, monofunctional vinyl ether and monofunctional N-vinyl compound, such as cyclic trimethylolpropane formal (meth)acrylate, 2-(meth)acryloyloxyethyl succinic acid, stearyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. Examples of the polymerizable surfactant include polymerizable silicone surfactant, polymerizable fluorine surfactant, and polymerizable acrylic surfactant. Commercially available polymerizable silicone surfactants include, for example, BYK-UV3500, 3505, 3530, 3570, 3575, and 3576 (manufactured by BYK), Tegorad 2100, 2200, 2250, 2300, 2500, 2600, 2700, 2800, 2010, and 2011 (manufactured by Evonik), EBECRYL 350 and 1360 (manufactured by Daicel-Allnex Corporation), and KP-410, 411, 412, 413, 414, 415, 416, 418, 420, 422, and 423 (manufactured by Shin-Etsu Silicones), and other silicone surfactants having a (meth)acryloyl group.Examples of the polymerizable fluorosurfactant include compounds having a perfluoroalkyl group and a polymerizable group. Examples of commercially available polymerizable fluorosurfactants include fluorosurfactants having a (meth)acryloyl group, such as Megafac RS-56, RS-72-K, RS-75, RS-76-E, RS-65-NS, RS-78, and RS-90 (manufactured by DIC Corporation). Examples of the polymerizable acrylic surfactant include compounds having a polymerizable group bonded to the side chain of a poly(meth)acrylic structure. Examples of commercially available polymerizable acrylic surfactant include CN821 (manufactured by Sartomer Corporation). The active energy ray curable inkjet ink may contain at least one type of polymerization initiator. The polymerization initiator is preferably a radical polymerization initiator that generates radicals, such as bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide or 1,3-di({α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]}oxy)-2,2-bis({α-[1-methylethylene)]}oxymethyl)propane.

[0032] The primer ink may be a clear ink that does not contain a coloring material, or a colored ink that contains a coloring material. The color of the coloring material may be any color, such as black, white, blue, red, green, yellow, orange, or the like, and is not particularly limited.

[0033] The ink layer 22 is formed on the primer layer 21 and is a layer showing letters, numbers, or symbols (hereinafter, letters, numbers, or symbols may be collectively referred to as letters, etc.), and / or design images such as illustrations or icons. The ink layer 22 may consist of only one layer, or may be two or more layers.

[0034] The colored portion 22A constitutes the characters and / or design images in the ink layer 22. For example, in FIG. 1, the colored portion 22A is a collection of bars and a group of numbers of a one-dimensional code printed in black. The colored portion 22A is a coating film of colored ink, which is an active energy ray curable inkjet ink containing a coloring material, and includes an ink cured product that is a cured product of the colored ink. The colored ink has the same basic structure as the active energy ray curable inkjet ink exemplified as the primer ink, and includes a coloring material. The coloring material is also called a coloring agent, and examples of the coloring material include dyes and pigments. From the viewpoint of durability such as heat resistance, light resistance, and water resistance, it is preferable that the coloring material is a pigment. As the pigment, either organic pigments or inorganic pigments that are usually commercially available can be used. Examples of the pigment include those described in "Dictionary of Pigments" edited by Seijiro Ito (published in 2000), "Industrial Organic Pigments" by W. Herbst and K. Hunger, and JP-A-2002-12607, JP-A-2002-188025, JP-A-2003-26978, and JP-A-2003-342503. The color of the coloring material may be any color, such as black, white, blue, red, green, yellow, orange, and is not particularly limited. The colored portion 22A may or may not have alkali peelability. In this embodiment, when the primer layer 21 has alkali peelability, it is more preferable that the colored portion 22A does not have alkali peelability. The colored portion 22A may be made of only the ink cured product, or may contain additives such as fillers or colorants such as pigments and dyes in addition to the ink cured product.

[0035] In this embodiment, the color ink has at least a first color ink having a first color as a coloring material, and a second color ink having a second color as a coloring material, which is different from the first color ink. The colors of the first color ink and the second color ink may be different from each other, and the colors are not particularly limited. For example, the first color ink is preferably any one selected from the group consisting of black ink, cyan ink, yellow ink, and magenta ink. The second color ink is preferably any one selected from the group consisting of black ink, cyan ink, yellow ink, and magenta ink and different from the first color ink. In addition to the first color ink and the second color ink, the color ink further has a third color ink and a fourth color ink, and the first color ink, the second color ink, the third color ink, and the fourth color ink are preferably yellow ink, magenta ink, cyan ink, and black ink, respectively. The printing unit 20 can be printed in full color, and a three-dimensional object with excellent cosmetic properties can be obtained. In this embodiment, the colors and the number of colors of the color inks are not limited to the above examples. The color inks may further include a color white ink.

[0036] FIG. 3 is a schematic cross-sectional view showing another example of the printed portion. In this embodiment, as shown in FIG. 3, the ink layer 22 may further have a background printed portion 22B between the primer layer 21 and the colored portion 22A. The background printed portion 22B is, for example, a rectangular white solid print in the printed portion 20 in FIG. 1. The background printed portion 22B includes a cured product of a background white ink, which is an active energy ray curable inkjet ink containing a white coloring material. The background white ink has the same basic configuration as the active energy ray curable inkjet ink exemplified as the primer ink, and includes a white coloring material. The white coloring material may be a white coloring material selected from the coloring materials exemplified as the coloring materials of the color inks, and is not particularly limited, but is, for example, titanium dioxide. The background printed portion 22B is preferably a solid print provided between the primer layer 21 and the information image portion 22A, and may be a single coat or two or more coats. The thickness of the background printed part 22B is not particularly limited, but is preferably 6 to 26 μm, and more preferably 11 to 15 μm. The background printed part 22B may or may not have alkali releasability. In this embodiment, when the primer layer 21 has alkali releasability, it is more preferable that the background printed part 22B does not have alkali releasability. The background printed part 22B may consist of only the cured product of the background white ink, or may contain additives such as a colorant such as a filler or a pigment or dye in addition to the cured product of the background white ink.

[0037] (3D object manufacturing equipment) 4 is a schematic diagram showing an example of a three-dimensional object manufacturing apparatus according to the present embodiment. The three-dimensional object manufacturing apparatus 100 includes a primer ink ejection head 101 for ejecting primer ink, a first irradiation device 121, an ejection head unit 110 including a first color ink ejection head 111 for ejecting a first color ink, and a second color ink ejection head 112 for ejecting a second color ink, a second irradiation device 122, and a transport device 105 (105a, 105b, 105c) for transporting the three-dimensional object 1 in this order.

[0038] The ejection head 101 for the primer ink is not particularly limited as long as it is an inkjet head used in an inkjet recording method. The inkjet recording method is not particularly limited as long as it is a method capable of recording an image, and known methods such as a continuous type or an on-demand type can be used. In this embodiment, the inkjet recording method is preferably an on-demand type. The on-demand type includes a piezo type and a thermal type, and in this embodiment, the piezo type is more preferable.

[0039] The first irradiation device 121 is a device that irradiates active energy rays to cure active energy ray-curable inkjet ink, and is a device that cures the primer ink attached to the outer surface of the three-dimensional object 1. The active energy rays are, for example, gamma rays, beta rays, electron beams, ultraviolet rays, and visible light. Of these, the active energy rays are preferably ultraviolet rays. The peak wavelength of the ultraviolet rays is not particularly limited, but is preferably 200 to 410 nm, and more preferably 250 to 400 nm. The light source for irradiating ultraviolet rays is not particularly limited, and is, for example, a lamp such as a mercury lamp or a metal halide lamp, a light-emitting diode such as an ultraviolet light-emitting diode (UV-LED), or a laser light source such as a gas laser, a solid-state laser, or an ultraviolet laser diode (UV-LD).

[0040] The first irradiation device 121 may be a provisional curing device for provisionally curing the primer ink, or a formal curing device for formally curing the primer ink. In this specification, "provisional curing" refers to polymerizing only a portion of the polymerizable monomer in the active energy ray-curable inkjet ink, and the irradiation of active energy rays for provisional curing is sometimes referred to as "pinning exposure." In addition, in this specification, "formal curing" refers to polymerizing substantially all of the polymerizable monomer in the active energy ray-curable inkjet ink, and the irradiation of active energy rays for formal curing is sometimes referred to as "formal exposure."

[0041] The ejection head unit 110 includes at least a first color ink ejection head 111 and a second color ink ejection head 112. As shown in Fig. 4, the ejection head unit 110 preferably further includes a third color ink ejection head 113 and a fourth color ink ejection head 114 in addition to the first color ink ejection head 111 and the second color ink ejection head 112. These color ink ejection heads 111, 112, 113, and 114 are preferably arranged along the transport path 106 of the transport device 105b. The color ink ejection heads 111, 112, 113, and 114 can be inkjet heads similar to the primer ink ejection head 101. The arrangement of the color ink ejection heads 111, 112, 113, and 114 in the ejection head unit 110 is not particularly limited, but for example, it is preferable to arrange, in order from the upstream side of the transport direction C of the transport device 105b, a black head that ejects black ink as the first color ink ejection head 111, a cyan head that ejects cyan ink as the second color ink ejection head 112, a magenta head that ejects magenta ink as the third color ink ejection head 113, and a yellow head that ejects yellow ink as the fourth color ink ejection head 114. The ejection droplet volume of each of the color ink ejection heads 111, 112, 113, and 114 is preferably 1 to 100 pL (picoliters), more preferably 3 to 80 pL, and even more preferably 3 to 50 pL.

[0042] The ejection head unit 110 may further include a color white ink ejection head (not shown) that ejects a color white ink. The order of the color white ink ejection head may be any order among the color ink ejection heads 111, 112, 113, and 114 included in the ejection head unit 110. For example, the color white ink ejection head may be disposed on the most upstream side of the transport direction C, i.e., between the first irradiation device 121 and the first color ink ejection head 111 in FIG. 4, between the first color ink ejection head 111 and the second color ink ejection head 112, between the second color ink ejection head 112 and the third color ink ejection head 113, between the third color ink ejection head 113 and the fourth color ink ejection head 114, or on the most downstream side of the transport direction C, i.e., between the fourth color ink ejection head 114 and the second irradiation device 122 in FIG. 4.

[0043] The second irradiation device 122 is a device that irradiates active energy rays to cure the active energy ray curable inkjet ink, and cures the color ink attached to the cured primer ink. The second irradiation device 122 is a temporary curing device for temporary curing the color ink. The second irradiation device 122 may also function as both a temporary curing device and a main curing device for the color ink by subjecting the color ink to pinning exposure and then main exposure. The second irradiation device 122 may be the same device as the first irradiation device 121.

[0044] The conveying device 105 (105a, 105b, 105c) is a device that moves the three-dimensional object 1 along the conveying path 106, and is, for example, a belt conveyor or a rotary table. In principle, the conveying device 105 (105a, 105b, 105c) preferably conveys the three-dimensional object 1 continuously at a constant speed while the manufacturing apparatus 100 is in operation, but may be temporarily stopped or may convey the three-dimensional object 1 intermittently, or may change the conveying speed, as necessary. The conveying device 105 (105a, 105b, 105c) includes a first conveying line 105a that conveys the three-dimensional object 1 before printing, a second conveying line 105b that conveys the three-dimensional object 1 to the printing area, and a third conveying line 105c that conveys the three-dimensional object 1 after printing. FIG. 4 shows an example of a rotary-type manufacturing device in which the first conveyor line 105a and the third conveyor line 105c are belt conveyors and the second conveyor line 105b is a rotary table, but the present invention is not limited thereto. For example, the first to third conveyor lines 105a, 105b, and 105c may all be belt conveyors in a linear manufacturing device. In addition, the conveyor 105 may be stopped, and the ejection head unit 110 may be moved to the stopped three-dimensional object 1 to perform printing. In FIG. 4 and FIG. 5, only one representative three-dimensional object 1 is illustrated, and the other three-dimensional objects 1 are omitted, and it is preferable that the conveyor 105 (105a, 105b, and 105c) conveys a plurality of three-dimensional objects 1. It is preferable that the plurality of three-dimensional objects 1 are arranged on the conveyor 105 (105a, 105b, and 105c) at a predetermined interval from each other. The three-dimensional objects 1 may be arranged in a single row on the conveying device 105 (105a, 105b, 105c) or in multiple rows (two or more rows). When the three-dimensional objects 1 are arranged in multiple rows, each component including the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122 may be arranged in multiple rows according to the row of the three-dimensional objects 1.In addition, each component including the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122 has been shown arranged radially outside the rotary table (transport device 105b) with respect to the transport path 106 of the three-dimensional object 1, but the present invention is not limited to this, and the components may be arranged radially inside the rotary table (transport device 105b) with respect to the transport path 106 of the three-dimensional object 1, or may be arranged on both the radially outside and radially inside sides of the rotary table (transport device 105b) with respect to the transport path 106 of the three-dimensional object 1.

[0045] The manufacturing apparatus 100 for the three-dimensional object 1 according to the present embodiment preferably further includes a rotation device (not shown) for the three-dimensional object 1. The rotation device for the three-dimensional object 1 is a device that rotates (spins) the three-dimensional object 1 around the central axis while moving the three-dimensional object 1 with the transport device 105. The rotation device for the three-dimensional object 1 is not particularly limited, but may be, for example, a turntable installed on the transport device 105, or a lifting and rotating device that lifts and rotates the three-dimensional object 1. When the rotation device for the three-dimensional object 1 is a turntable, the turntable rotates the three-dimensional object 1 around the central axis of the three-dimensional object 1 by rotating the turntable while the three-dimensional object 1 is placed on the turntable and moved along the transport path 106 by the transport device 105. When the rotation device for the three-dimensional object 1 is a lifting and rotating device, the lifting and rotating device lifts the three-dimensional object 1 from the transport surface of the transport device 105 and rotates the lifted three-dimensional object 1 around the central axis of the three-dimensional object 1. By providing the rotation device to the manufacturing apparatus 100, the three-dimensional object 1 can be rotated around its axis to perform printing on the entire circumference of the side surface of the three-dimensional object 1. In addition, by rotating the three-dimensional object 1 on the spot using a rotation device after the primer ink has been applied, time for leveling the primer ink can be secured.

[0046] The manufacturing apparatus 100 for the three-dimensional object 1 according to the present embodiment preferably further includes an alignment device (not shown) for the three-dimensional object 1. The alignment device for the three-dimensional object 1 is a device that orients the three-dimensional object 1 conveyed by the conveying device 105 in a predetermined direction. Orienting the three-dimensional object 1 in a predetermined direction means, for example, facing the surface on which the printing unit 20 (for example, shown in FIG. 1) is to be formed to each component including the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122. By providing the alignment device in the manufacturing apparatus 100, it is possible to suppress printing misalignment. In addition, the printing unit 20 can be provided at a predetermined location. The alignment device for the three-dimensional object 1 is not particularly limited, but is, for example, a clamping tool that clamps the three-dimensional object 1 and moves it to a predetermined position on the conveying surface of the conveying device 105, or an alignment rib that is provided on the conveying surface of the conveying device 105 and guides the three-dimensional object 1 to a predetermined position on the conveying surface.

[0047] It is preferable that the manufacturing apparatus 100 for the three-dimensional object 1 according to this embodiment further includes a holding device (not shown) for the three-dimensional object 1. The holding device for the three-dimensional object 1 is a device that holds the three-dimensional object 1 transported by the transport device 105. The holding device for the three-dimensional object 1 is not particularly limited, and may be, for example, a clamping arm that grips the three-dimensional object 1, or a holding guide that supports the three-dimensional object 1. By providing the manufacturing apparatus 100 with a holding device, printing misalignment can be suppressed. Also, the printing unit 20 can be provided at a predetermined location.

[0048] "The conveying device 105 (105a, 105b, 105c) conveying the three-dimensional object 1 in this order" means that the conveying device 105 conveys the three-dimensional object 1 so that the three-dimensional object 1 is processed in the order of at least the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122. In this embodiment, it is preferable that the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122 are arranged in this order from the upstream side along the conveying path 106. In this embodiment, other components may be arranged between the respective components of the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122.

[0049] In the conventional manufacturing apparatus for a three-dimensional object, when two or more kinds of color inks are used, in order to prevent the inks from bleeding, the ejection heads of the color inks and the irradiation devices for the color inks are arranged alternately, and the adhesion and pinning of each color ink are performed alternately. Therefore, when the number of colors of color inks increases, it is necessary to install a set of ejection heads and irradiation devices corresponding to the number of colors, which causes a problem of the manufacturing apparatus becoming larger. In the manufacturing apparatus 100 for a three-dimensional object according to this embodiment, two or more kinds of color inks are pinned together in one irradiation device to make it partially pinning-free, thereby reducing the number of irradiation devices and reducing the size of the manufacturing apparatus. In addition, by adopting a revolution printing method in which the three-dimensional object 1 is moved by the conveying device 105 while printing at high speed using an inkjet method, it is possible to obtain image quality that ensures the visibility of characters such as ingredient indications of products even if it is partially pinning-free.

[0050] The three-dimensional object manufacturing apparatus 100 according to this embodiment includes a configuration further including a third irradiation device 123 arranged downstream of the transport device 105 relative to the second irradiation device 122, as shown in FIG.

[0051] The third irradiation device 123 is a device that irradiates active energy rays to cure the active energy ray curable inkjet ink. The third irradiation device 123 is a main curing device for main curing of the color ink. The third irradiation device 123 may be the same device as the first irradiation device 121. The third irradiation device 123 is preferably disposed downstream of the second irradiation device 122 on the transport path 106.

[0052] 5 is a schematic diagram showing another example of the three-dimensional object manufacturing apparatus according to the present embodiment. In the three-dimensional object manufacturing apparatus 100 according to the present embodiment, the ink layer 22 further includes a background printing section 22B between the primer layer 21 and the coloring section 22A as shown in FIG. 3, and the background printing section 22B includes a cured product of a background white ink, which is an active energy ray curable inkjet ink containing a white coloring material, and the three-dimensional object manufacturing apparatus 100 further includes a background printing section forming unit 130 between the first irradiation device 121 and the ejection head unit 110 as shown in FIG. 5, and the background printing section forming unit 130 preferably includes a background white ink ejection head 131 for ejecting the background white ink and a fourth irradiation device 132 in this order.

[0053] The background printing unit 130 is preferably disposed between the first irradiation device 121 and the first color ink ejection head 111 .

[0054] The background white ink ejection head 131 can be an inkjet head similar to the primer ink ejection head 101 .

[0055] The fourth irradiation device 132 is a device that irradiates active energy rays to cure the active energy ray curable inkjet ink, and is a device for curing the background white ink. The fourth irradiation device 132 is preferably disposed downstream of the background white ink ejection head 131 on the transport path 106. The fourth irradiation device 132 may be a device similar to the first irradiation device 121. The fourth irradiation device 132 may be a temporary curing device for temporary curing the background white ink, or a permanent curing device for permanent curing the background white ink. By providing the fourth irradiation device 132 upstream of the transport path 6 of the ejection head unit 110, the background white ink can be cured prior to the ink of the colored portion, and the colored ink can be fixed more stably on the background printed portion. As a result, a clearer image can be obtained.

[0056] In the three-dimensional object manufacturing apparatus 100 according to the present embodiment, the transport distance of the three-dimensional object 1 of the transport device 105 between the primer ink ejection head 101 and the first irradiation device 121 is preferably longer than the transport distance of the three-dimensional object 1 of the transport device 105 between the ejection head unit 110 and the second irradiation device 122. The transport distance of the three-dimensional object 1 of the transport device 105 between the ejection head unit 110 and the second irradiation device 122 is the transport distance of the three-dimensional object 1 of the transport device 105 between the color ink ejection head (the fourth color ink ejection head 114 in FIG. 4) arranged at the most downstream of the transport path 106 of the ejection head unit 110 and the second irradiation device 122. Here, if the transport speed of the three-dimensional object 1 in the section between the primer ink ejection head 101 and the first irradiation device 121 is the same as the transport speed of the three-dimensional object 1 in the section between the ejection head unit 110 and the second irradiation device 122, the transport distance and the transport time are in a proportional relationship in both sections. For example, when the primer ink ejection head 101, the first irradiation device 121, the ejection head unit 110, and the second irradiation device 122 are all located along the rotary table as in the second conveying line 105b shown in FIG. 4, the conveying distance and the conveying time are in a proportional relationship in both sections. When the conveying distance and the conveying time are in a proportional relationship in both sections, the conveying distance of the three-dimensional object 1 of the conveying device 105 between the primer ink ejection head 101 and the first irradiation device 121 is made longer than the conveying distance of the three-dimensional object 1 of the conveying device 105 between the ejection head unit 110 and the second irradiation device 122, so that the conveying time in the section between the primer ink ejection head 101 and the first irradiation device 121 can be secured longer. As a result, the primer layer obtained by leveling the primer ink can be made flat, while suppressing the bleeding of the color ink, thereby obtaining a clearer image. By leveling the primer ink, the primer cured product can be made into a continuous film without pinholes through which the ink cured product can penetrate, and all of the ink cured product can be positioned on the primer cured product. As a result, there is no portion where the ink layer 22 is in direct contact with the outer surface of the three-dimensional object 1, and alkali peelability is ensured over the entire area, including the center portion, of the printed portion 20.The transport distance of the three-dimensional object 1 by the transport device 105 between the primer ink ejection head 101 and the first irradiation device 121 is preferably 2 to 10 times, more preferably 2.5 to 8 times, and even more preferably 3 to 5 times, the transport distance of the three-dimensional object 1 by the transport device 105 between the ejection head unit 110 and the second irradiation device 122.

[0057] In the three-dimensional object manufacturing apparatus 100 according to the present embodiment, the transport distance of the transport device 105 between the primer ink ejection head 101 and the first irradiation device 121 is more preferably longer than the transport distance of the three-dimensional object 1 between the color ink ejection head (the first color ink ejection head 111 in FIG. 4) arranged at the most upstream of the transport path 106 among the ejection head unit 110 and the second irradiation device 122. The transport distance of the three-dimensional object 1 between the primer ink ejection head 101 and the first irradiation device 121 is preferably 2 to 10 times, more preferably 2.5 to 8 times, and even more preferably 3 to 5 times, the transport distance of the three-dimensional object 1 between the color ink ejection head (the first color ink ejection head 111 in FIG. 4) arranged at the most upstream of the transport path 106 among the ejection head unit 110 and the second irradiation device 122. By setting the thickness within this range, the primer ink can be leveled while the color ink can be cured in a short time after landing, which prevents the ink dots from spreading, making it possible to print designs with greater detail.

[0058] (Manufacturing method for three-dimensional objects) The method for producing a three-dimensional object according to this embodiment is a method for forming a printed part 20 having a primer layer 21 and an ink layer 22 provided on the primer layer 21 on the outer surface of a three-dimensional object 1 as shown in Fig. 2 or 3. The method for producing a three-dimensional object according to this embodiment includes a color ink applying step including at least a first color ink applying step of applying a first color ink onto a cured product of a primer ink and a second color ink applying step of applying a second color ink onto the cured product of the primer ink, and a second irradiation step of irradiating a color ink group including the first color ink and the second color ink applied onto the cured product of the primer ink in the color ink applying step with active energy rays.

[0059] The method for manufacturing a three-dimensional object according to this embodiment includes a form further including, prior to the color ink application step, a primer ink application step of applying primer ink to the outer surface of the three-dimensional object 1, and a first irradiation step of irradiating the primer ink applied to the outer surface of the three-dimensional object 1 with active energy rays.

[0060] Next, each step will be described by taking as an example a case where the three-dimensional object manufacturing apparatus 100 shown in FIG. 4 or FIG. 5 is used, but the method for manufacturing a three-dimensional object according to this embodiment is not limited to this manufacturing apparatus.

[0061] The three-dimensional object 1 is transferred from the transport device 105a to the transport device 105b, transported to the printing area, and moved to the ink landing range of the primer ink ejection head 101. In the primer ink deposition step, primer ink is ejected from the primer ink ejection head 101. This causes the primer ink to adhere to the outer surface of the three-dimensional object 1. The amount of primer ink ejected from the primer ink ejection head 101 is not particularly limited, but is preferably 1 to 100 pL (picoliters), more preferably 3 to 80 pL, and even more preferably 3 to 50 pL.

[0062] The three-dimensional object 1 with the primer ink attached thereto is transported in the transport direction C and moves into the irradiation range of the active energy ray from the first irradiation device 121. In the first irradiation step, the active energy ray is irradiated from the first irradiation device 121. In the first irradiation step, the active energy ray from the first irradiation device 121 may be a pinning exposure or a main exposure. Of these, it is more preferable that in the first irradiation step, the active energy ray from the first irradiation device 121 is a pinning exposure.

[0063] Next, the three-dimensional object 1 moves to an ink landing range of the first color ink ejection head 111. The color ink applying step includes at least a first color ink applying step and a second color ink applying step. In addition to the first color ink applying step and the second color ink applying step, the color ink applying step may further include a third color ink applying step of applying a third color ink onto the cured product of the primer ink and a fourth color ink applying step of applying a fourth color ink onto the cured product of the primer ink.

[0064] In the first color ink application step, the first color ink is ejected from the first color ink ejection head 111. This causes the first color ink to be attached onto the cured primer of the three-dimensional object 1. The first color ink is, for example, a black ink.

[0065] The three-dimensional object 1 with the first color ink attached thereto is transported in the transport direction C and moves to the ink landing range of the second color ink ejection head 112. In the second color ink attachment process, the second color ink is ejected from the second color ink ejection head 112. This causes the second color ink to adhere to the cured primer of the three-dimensional object 1. The second color ink is, for example, a cyan ink.

[0066] The three-dimensional object 1 with the second color ink attached thereto is transported in the transport direction C, and moves sequentially to the ink landing range of the third color ink ejection head 113 and the ink landing range of the fourth color ink ejection head 114, and the third color ink and the fourth color ink are attached to the cured primer of the three-dimensional object 1 in the same manner as in the first color ink attachment process and the second color ink attachment process. The third color ink is, for example, a magenta ink, and the fourth color ink is, for example, a yellow ink. The amount of each color ink ejected from each color ink ejection head 111, 112, 113, and 114 is not particularly limited, but is preferably 1 to 100 pL (picoliters), more preferably 3 to 80 pL, and even more preferably 3 to 50 pL.

[0067] The color ink applying step may further include a color white ink applying step of applying a color white ink onto the cured product of the primer ink. The timing of performing the color white ink applying step may be, for example, after the first irradiation step and before the first color ink applying step, i.e., at the very beginning of the color ink applying step, between the first color ink applying step and the second color ink applying step, between the second color ink applying step and the third color ink applying step, between the third color ink applying step and the third color ink applying step, or just before the second irradiation step, i.e., at the very end of the color ink applying step. In the present invention, the timing of performing the color white ink applying step is not particularly limited.

[0068] The three-dimensional object 1 with the color inks attached thereto is transported in the transport direction C and moves into the irradiation range of the active energy rays from the second irradiation device 122. In the second irradiation step, active energy rays are irradiated from the second irradiation device 122. The second irradiation step is a step of collectively curing a group of color inks including at least the first color ink and the second color ink. In the second irradiation step, the active energy rays from the second irradiation device 122 are preferably pinning exposure. Furthermore, the second irradiation step may be a step of further curing the provisionally cured primer product provisionally cured in the first irradiation step in addition to provisionally curing the group of color inks.

[0069] In the three-dimensional object manufacturing apparatus 100 according to this embodiment, the printing speed in the color ink application step is preferably 80 to 600 bpm (bottles per minutes), and more preferably 100 to 300 bpm. Here, bpm (bottles per minutes) is an index indicating the number of three-dimensional objects 1 that can be printed per minute. For example, in the manufacturing apparatus 100 shown in FIG. 5, the above-mentioned printing speed can be achieved by adjusting the rotation speed of the rotary table, which is the second conveyor line 105b.

[0070] In the conventional manufacturing method of a three-dimensional object, when two or more kinds of color inks are used, the application step and the irradiation step are alternately performed for each color ink to prevent the inks from bleeding. Therefore, when the number of colors of color inks increases, it is necessary to perform an irradiation step corresponding to the number of colors, which increases the manufacturing process. In the manufacturing method of a three-dimensional object according to the present embodiment, the manufacturing method can be simplified by pinning two or more kinds of color inks together in one irradiation step to make it partially pinning-free. In addition, by adopting a revolution printing method in which the three-dimensional object 1 is printed at high speed by an inkjet method while moving, it is possible to obtain image quality that ensures the visibility of characters such as ingredient indications of products even if it is partially pinning-free.

[0071] The method for producing a three-dimensional object according to this embodiment includes an embodiment further including a third irradiation step of further irradiating the color ink group with active energy rays after the second irradiation step. After the second irradiation step, the three-dimensional object 1 is transported in the transport direction C and moves to an irradiation range of the active energy rays from the third irradiation device 123. In the third irradiation step, active energy rays are irradiated from the third irradiation device 123. In the third irradiation step, the active energy rays from the third irradiation device 123 are preferably main exposure.

[0072] In the method for manufacturing a three-dimensional object according to this embodiment, the ink layer 22 further has a background printed portion 22B between the primer layer 21 and the cured product of the color ink, as shown in FIG. 3, and the background printed portion 22B includes a cured product of a background white ink, which is an active energy ray-curable inkjet ink containing a white colorant. The method for manufacturing a three-dimensional object further has a background printed portion forming step between the first irradiation step and the color ink applying step, and it is preferable that the background printed portion forming step has a background white ink applying step of applying the background white ink onto the primer layer, and a fourth irradiation step of irradiating the background white ink applied onto the primer layer with active energy rays.

[0073] In the background white ink adhering step, after the first irradiation step, as shown in Fig. 5, the three-dimensional object 1 is transported in the transport direction C, and when it moves into the ink landing range of the background white ink ejection head 131, background white ink is ejected from the background white ink ejection head 131. As a result, the background white ink adheres onto the cured primer of the three-dimensional object 1.

[0074] The three-dimensional object 1 with the background white ink attached thereto is transported in the transport direction C and moves to the irradiation range of the active energy ray of the fourth irradiation device 132. In the fourth irradiation step, the active energy ray is irradiated from the fourth irradiation device 132. In the fourth irradiation step, the active energy ray from the fourth irradiation device 132 may be pinning exposure or main exposure. Of these, it is more preferable that in the fourth irradiation step, the active energy ray from the fourth irradiation device 132 is pinning exposure. By curing the background white ink prior to the ink of the colored portion, the colored ink can be fixed more stably on the background printed portion. As a result, a clearer image can be obtained.

[0075] In this embodiment, it is preferable to temporarily cure two or more types of color inks together and then fully cure them.

[0076] In each of the first, second, third and fourth irradiation steps, the reaction rate of the color ink after pinning exposure is lower than the reaction rate of the color ink after main exposure. The reaction rate of the color ink after pinning exposure is not particularly limited, but is preferably 10 to 80%, and more preferably 15 to 75%. By setting it in such a range, the image quality of the obtained image is improved. The reaction rate of the color ink after main exposure is not particularly limited, but is preferably more than 80% and 100% or less, and more preferably 85 to 100%. The reaction rate of the color ink is determined by the following method. A substrate is prepared that has been operated until the end of irradiation of the ink with active energy rays. A sample piece (hereinafter referred to as a post-irradiation sample piece) having a size of 20 mm x 50 mm is cut out from the region where the ink film of this substrate exists. The cut-out post-irradiation sample piece is immersed in 10 mL of THF (tetrahydrofuran) for 24 hours to obtain an eluate in which the ink is eluted. The amount of polymerizable monomer (hereinafter referred to as "amount of monomer X1 after irradiation") of the obtained eluate is determined by high performance liquid chromatography. Separately, the same operation as above is carried out except that the ink on the substrate is not irradiated with active energy rays, and the amount of polymerizable monomer (hereinafter referred to as "amount of monomer X1 before irradiation") is determined. Based on the amount of monomer X1 after irradiation and the amount of monomer X1 before irradiation, the reaction rate (%) of the ink is calculated by the following (Equation 1). (Equation 1) Ink reaction rate (%) = ((monomer amount before irradiation X1 - monomer amount after irradiation X1) / monomer amount before irradiation X1) x 100

[0077] The exposure dose of active energy rays for pinning exposure is 0.1 to 100 mJ / cm 2 is preferably 0.2 to 60 mJ / cm 2 It is more preferable that the amount of exposure to the active energy ray is within such a range. By setting the amount of exposure to the active energy ray within such a range, the color ink can be pinned. 2 is preferably 0.5 to 800 mJ / cm 2 It is more preferable that the amount of the color ink is within such a range.

[0078] In the method for manufacturing a three-dimensional object according to the present embodiment, the time from the end of the primer ink application process to the start of irradiation of active energy rays in the first irradiation process is preferably longer than the time from the end of the color ink application process to the start of irradiation of active energy rays in the second irradiation process. The time from the end of the color ink application process to the start of irradiation of active energy rays in the second irradiation process is the time from the time when the set total amount of color ink from the color ink ejection head (the fourth color ink ejection head 114 in FIG. 4) arranged at the most downstream of the conveying path 106 in the color ink application process has landed on the cured product of the primer ink to the time when irradiation of active energy rays is started in the second irradiation device 122. The primer layer obtained by leveling the primer ink is made flat, while the bleeding of the color ink is suppressed, and a clearer image can be obtained. By lengthening the time from the end of the primer ink application process to the start of irradiation of active energy rays in the first irradiation process, the primer ink can be leveled. The method for lengthening the time from the primer ink application step to the start of irradiation of active energy rays in the first irradiation step is not particularly limited, but includes, for example, a method of lengthening the transport distance of the three-dimensional object 1, and a method of rotating the three-dimensional object 1 on the spot after the primer ink is applied and holding it until the primer ink is leveled. The time from the time when the set total amount of primer ink has landed on the outer surface of the three-dimensional object 1 in the primer ink application step to the start of irradiation of active energy rays in the first irradiation step is preferably 2 to 10 times, more preferably 2.5 to 8 times, and even more preferably 3 to 5 times, the time from the end of the color ink application step to the start of irradiation of active energy rays in the second irradiation step.

[0079] The time from the time when the entire amount of the primer ink has landed on the outer surface of the three-dimensional object 1 in the primer ink application process to the time when the irradiation of the active energy rays in the first irradiation process starts is preferably 0.5 to 60 seconds, more preferably 1.0 to 10 seconds. By setting it in such a range, the primer ink can be sufficiently leveled. On the other hand, the time from the time when the entire amount of the color ink discharged from the color ink discharge head at the most downstream of the transport path 6 (for example, the fourth color ink discharge head 114 in FIG. 4) has landed on the primer cured product in the color ink application process to the time when the irradiation of the active energy rays in the second irradiation process starts is preferably 0.1 to 60 seconds, more preferably 0.3 to 1.0 seconds. By setting it in such a range, the bleeding between the color inks can be further suppressed.

[0080] In the method for manufacturing a three-dimensional object according to this embodiment, it is more preferable that the time from the end of the primer ink application step to the start of irradiation with active energy rays in the first irradiation step is longer than the time from the time when the set total amount of color inks discharged from the color ink discharge head (for example, the first color ink discharge head 111 in FIG. 4) at the most upstream of the transport path 6 in the color ink application step has landed on the cured primer product to the time when irradiation with active energy rays is started in the second irradiation step. The primer layer obtained by leveling the primer ink can be made flatter, while the bleeding of the color inks is further suppressed, thereby obtaining a clearer image.

[0081] In this embodiment, the time from the time when the set amount of color inks discharged from the color ink discharge head at the most upstream of the transport path 6 (for example, the first color ink discharge head 111 in FIG. 4) finishes landing on the cured primer product in the color ink application step to the time when the irradiation of active energy rays starts in the second irradiation step is preferably 0.2 to 60 seconds, and more preferably 0.4 to 1.0 seconds. By setting it in such a range, it is possible to further suppress bleeding between color inks. The time from the time when the set amount of primer inks finished landing on the outer surface of the three-dimensional object 1 in the primer ink application step to the time when the irradiation of active energy rays starts in the first irradiation step is preferably 2 to 10 times, more preferably 2.5 to 8 times, and even more preferably 3 to 5 times, the time from the time when the set amount of color inks discharged from the color ink discharge head at the most upstream of the transport path 6 finishes landing on the cured primer product in the color ink application step to the time when the irradiation of active energy rays starts in the second irradiation step.

[0082] In the manufacturing method of the three-dimensional object according to the present embodiment, the three-dimensional object 1 has a bottom surface and a side surface, and is transported with the bottom surface facing the transport device 105 with the side surface standing up, and the primer ink ejection head 101 and the color ink ejection heads 111, 112, 113, and 114 of the ejection head unit 110 preferably eject ink onto the side surface of the three-dimensional object 1. Here, when the three-dimensional object 1 is a container as shown in FIG. 1, for example, the container is transported with its central axis facing vertically. In this way, by transporting the three-dimensional object 1 in an upright state, the manufacturing device 100 can be made smaller. In addition, the printing portion 20 can be formed on the side surface of the three-dimensional object 1 more efficiently. [Explanation of symbols]

[0083] 1 three-dimensional object 10 Container body 11 Mouth 12 Torso 12a Upper torso 12b Body 12c lower torso 20 Printing Department 21 Primer layer 22 Ink layer 22A Colored section 22B Background printing section 100 Three-dimensional object manufacturing equipment 101 Primer ink ejection head 105 (105a, 105b, 105c) Conveyor device 106 Transport Route 110 Ejection head unit 111 First color ink ejection head 112 Second color ink ejection head 113 Third color ink ejection head 114 Fourth color ink ejection head 121 1st irradiation device 122 Second irradiation device 123 Third irradiation device 130 Background printing unit 131 Background white ink ejection head 132 4th irradiation device C. Conveying direction

Claims

1. 1. An apparatus for manufacturing a three-dimensional object, which forms a printed portion having a primer layer and an ink layer provided on an outer surface of a three-dimensional object, the primer layer includes a cured product of a primer ink that is an active energy ray-curable inkjet ink, the ink layer has a color portion, the color portion including a cured product of a color ink that is an active energy ray-curable ink-jet ink containing a color material; The color ink includes at least a first color ink and a second color ink having a different color from the first color ink, The three-dimensional object manufacturing apparatus comprises: a primer ink ejection head that ejects the primer ink; A first irradiation device; an ejection head unit including a first color ink ejection head that ejects the first color ink and a second color ink ejection head that ejects the second color ink; A second irradiation device; and a conveying device that conveys the three-dimensional object in this order.

2. The apparatus for manufacturing a three-dimensional object according to claim 1, further comprising a third irradiation device disposed downstream of the transport device with respect to the second irradiation device.

3. The ink layer further includes a background printing portion between the primer layer and the color portion, the background printed portion includes a cured product of a background white ink, which is an active energy ray-curable inkjet ink containing a white colorant, the three-dimensional object manufacturing apparatus further includes a background printing unit between the first irradiation device and the ejection head unit, The background printing unit includes: a background white ink ejection head that ejects the background white ink; A fourth irradiation device; 3. The apparatus for manufacturing a three-dimensional object according to claim 1, further comprising:

4. The three-dimensional object manufacturing apparatus according to claim 1 or 2, characterized in that a transport distance of the three-dimensional object of the transport device between the primer ink ejection head and the first irradiation device is longer than a transport distance of the three-dimensional object of the transport device between the ejection head unit and the second irradiation device.

5. A method for manufacturing a three-dimensional object, comprising forming a printed portion having a primer layer and an ink layer provided on the primer layer on an outer surface of the three-dimensional object, comprising: the primer layer includes a cured product of a primer ink that is an active energy ray-curable inkjet ink, the ink layer has a color portion, the color portion including a cured product of a color ink that is an active energy ray-curable ink-jet ink containing a color material; The color ink includes at least a first color ink and a second color ink having a different color from the first color ink, The method for producing the three-dimensional object includes the steps of: a color ink applying step including at least a first color ink applying step of applying the first color ink onto the cured product of the primer ink, and a second color ink applying step of applying the second color ink onto the cured product of the primer ink; a second irradiation step of irradiating with active energy rays a group of color inks including the first color ink and the second color ink adhered onto the cured product of the primer ink in the color ink adherence step; A method for manufacturing a three-dimensional object, comprising the steps of:

6. In the method for producing a three-dimensional object, before the color ink application step, a primer ink applying step of applying the primer ink to an outer surface of the three-dimensional object; a first irradiation step of irradiating the primer ink attached to the outer surface of the three-dimensional object with active energy rays; The method for manufacturing a three-dimensional object according to claim 5, further comprising:

7. The method for producing the three-dimensional object includes the steps of: After the second irradiation step, 6. The method for producing a three-dimensional object according to claim 5, further comprising a third irradiation step of further irradiating the color inks with active energy rays.

8. The ink layer further has a background printed portion between the primer layer and the cured product of the color ink, the background printed portion includes a cured product of a background white ink, which is an active energy ray-curable inkjet ink containing a white colorant, The method for manufacturing a three-dimensional object further includes a background printing portion forming step between the first irradiation step and the color ink applying step, The background printing portion forming step includes: a background white ink applying step of applying the background white ink onto the primer layer; a fourth irradiation step of irradiating the background white ink attached on the primer layer with active energy rays; The method for manufacturing a three-dimensional object according to claim 6, further comprising the steps of:

9. 7. The method for manufacturing a three-dimensional object according to claim 6, wherein a time from the end of the primer ink application step to the start of irradiation of the active energy rays in the first irradiation step is longer than a time from the end of the color ink application step to the start of irradiation of the active energy rays in the second irradiation step.

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