printer

Abstract

Ensure the brightness of the color inks. [Solution] The printer 10 includes a color nozzle row 34A for ejecting color ink, a metallic nozzle row 34Bb for ejecting metallic ink, a light irradiation device 35 for irradiating light onto the material to be printed 5, and a control device 60. The control device 60 includes a metallic printing unit 63 that ejects metallic ink onto the material to be printed 5 to form a metallic layer L12, a color printing unit 64 that ejects color ink onto the metallic layer L12 to form a color printing layer L13, a pinning control unit 65 that irradiates the color printing layer L13 with light from the light irradiation device 35 at a pinning peak illuminance L21 to perform pinning, and a curing control unit 66 that, after pinning to the color printing layer L13, irradiates the color printing layer L13 with light at a curing peak illuminance L22 that is higher than the pinning peak illuminance L21 to perform curing.

Description

Technical Field

[0001] The present invention relates to a printer.

Background Art

[0002] For example, Patent Document 1 discloses an image forming apparatus. The image forming apparatus includes a metallic ink ejection head that ejects metallic ink onto a medium, a color ink ejection head that ejects color ink onto the medium, and an irradiation unit that irradiates light onto the metallic ink on the medium.

[0003] When printing on a medium, first, the metallic ink ejection head ejects metallic ink onto a first region of the medium. The irradiation unit irradiates light onto the metallic ink in the first region. The color ink ejection head ejects color ink onto the first region irradiated with light.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the case of printing in which color ink is ejected onto metallic ink as described above, the luminance of the color ink may not be sufficiently obtained.

[0006] The present invention has been made in view of this point, and an object thereof is to provide a printer capable of ensuring the luminance of color ink.

Means for Solving the Problems

[0007] The printer according to the present invention includes a support base for supporting a printing medium, an ink head for ejecting ink toward the printing medium supported on the support base, a light irradiation device for irradiating light on the printing medium supported on the support base, and a control device. The ink head includes a color nozzle row having color nozzles for ejecting color ink and a metallic nozzle row having metallic nozzles for ejecting metallic ink. The control device includes a metallic printing unit, a color printing unit, a pinning control unit, and a curing control unit. The metallic printing unit ejects the metallic ink onto the printing medium supported on the support base to form a metallic layer. The color printing unit ejects the color ink onto the metallic layer formed on the printing medium to form a color printing layer. The pinning control unit irradiates light from the light irradiation device at a pinning peak illuminance toward the color printing layer to perform pinning on the color printing layer. The curing control unit, after the pinning on the color printing layer by the pinning control unit, irradiates light from the light irradiation device at a curing peak illuminance higher than the pinning peak illuminance toward the color printing layer to perform curing on the color printing layer.

[0008] According to the above printer, even when a color printing layer is formed on a metallic layer, pinning is performed on the color printing layer to semi-cure the color printing layer. Then, curing is performed on the color printing layer on which pinning has been performed to completely cure the color printing layer. Thus, by performing pinning on the color printing layer, the luminance of the color ink can be ensured.

Advantages of the Invention

[0009] According to the present invention, it is possible to provide a printer capable of ensuring the luminance of color ink.

Brief Description of the Drawings

[0010] [Figure 1]This is a perspective view showing a printer according to an embodiment. [Figure 2] This is a front view showing a printer according to an embodiment. [Figure 3] This is a block diagram of the printer according to the embodiment. [Figure 4] This is a schematic diagram showing the configuration of the bottom surface of the ink head and light irradiation device. [Figure 5] This is a schematic cross-sectional view showing a substrate with a primer layer, a metallic layer, and a color printing layer formed on it. [Figure 6] This is a flowchart showing the printing procedure. [Figure 7] This is a schematic plan view showing the state of the light irradiation device when curing the primer layer. [Figure 8] This is a schematic plan view showing the state of the light irradiation device when performing pinning and curing on a metallic layer. [Figure 9] This is a schematic plan view showing the state of the light irradiation device when performing pinning and curing on a color printed layer. [Modes for carrying out the invention]

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Naturally, the embodiment described herein is not intended to particularly limit the present invention. Furthermore, the same reference numerals are used for members and parts that perform the same function, and redundant explanations are omitted or simplified as appropriate.

[0012] Figure 1 is a perspective view showing the printer 10 according to this embodiment. Figure 2 is a front view showing the printer 10 according to this embodiment. Figure 3 is a block diagram of the printer 10 according to this embodiment. In the following description, when a user views the printer 10 from the front, the direction away from the printer 10 is considered the front, and the direction towards the printer 10 is considered the rear. Left, right, up, and down refer to the left, right, up, and down directions when the user views the printer 10 from the front. The symbols F, Rr, L, R, U, and D in the drawings refer to the front, rear, left, right, up, and down directions, respectively. The symbol Y in the drawings indicates the main scanning direction. Here, the main scanning direction Y is the left-right direction. The symbol X indicates the sub-scanning direction. The sub-scanning direction X intersects (is perpendicular in this case) the main scanning direction Y in a plan view. The sub-scanning direction X is, for example, the front-back direction. The symbol Z indicates the height direction, or in other words, the up-down direction. However, these directions are merely defined for the sake of explanation and do not in any way limit the installation configuration of the printer 10, nor do they limit the present invention in any way.

[0013] As shown in Figure 2, the printer 10 ejects ink onto the substrate 5 to perform printing. The substrate 5 is, for example, recording paper. However, the substrate 5 is not limited to recording paper. For example, the substrate 5 may include relatively thick materials such as sheets made from resin materials such as PVC or polyester, metal plates, glass plates, or wooden boards. The substrate 5 may also be a three-dimensional object such as a smartphone case.

[0014] Printer 10 is an inkjet printer, a so-called inkjet printer. Printer 10 is a so-called flatbed type printer, and is configured such that when the support base 25 (see Figure 2), described later, moves in the sub-scanning direction X, the material to be printed 5 (see Figure 2) also moves in the sub-scanning direction X. However, printer 10 may also be a so-called roll-to-roll type printer, in which only the material to be printed 5 is moved in the sub-scanning direction X while the roll-shaped material to be printed 5 is unfolded.

[0015] As shown in Figure 1, the printer 10 comprises a printer body 11 and a cover 12. The printer body 11 is, for example, rectangular and case-shaped. However, the shape of the printer body 11 is not particularly limited. The printer body 11 has an internal space. Printing takes place in this internal space. As shown in Figure 2, an opening 15 is formed at the front of the printer body 11.

[0016] The cover 12 is supported by the printer body 11 so that the opening 15 can be opened and closed. The cover 12 is configured to rotate around its rear end as an axis. As shown in Figure 1, windows 16 are provided on the front and top of the cover 12. The windows 16 are made of a transparent or translucent material, such as an acrylic plate. The user can see the internal space of the printer body 11 through the windows 16.

[0017] In this embodiment, as shown in Figure 1, the printer 10 is equipped with an operation panel 20. The operation panel 20 is provided on the printer body 11. Specifically, the operation panel 20 is provided on the upper right part of the printer body 11, but the position of the operation panel 20 relative to the printer body 11 is not particularly limited. The operation panel 20 has a display screen 21 that displays information about the status and mode of the printer 10, and operation keys 22. The user can display various information about the status and mode of the printer 10 on the display screen 21 by operating, for example, the operation keys 22. In this embodiment, the operation keys 22 are composed of physical buttons, but they may also be implemented by a touch panel provided on the display screen 21.

[0018] Next, the internal configuration of the printer 10 according to this embodiment will be described. As shown in Figure 2, the printer 10 is equipped with a support base 25. The support base 25 supports the object to be printed 5. Here, the object to be printed 5 is placed on the upper surface of the support base 25. Printing is performed on the support base 25. For example, ink is ejected onto the object to be printed 5 supported by the support base 25. Here, the upper surface of the support base 25 is a flat surface that extends in the main scanning direction Y and the sub-scanning direction X, and functions as a support surface for supporting the object to be printed 5.

[0019] As shown in Figure 2, the printer 10 comprises a guide rail 28, a carriage 30, an ink head 32, and a light irradiation device 35. The guide rail 28 is located in the internal space of the printer body 11 and is fixed to the printer body 11. The guide rail 28 is positioned above the support base 25. The guide rail 28 extends in the main scanning direction Y. The carriage 30 is slidably mounted on the guide rail 28. The carriage 30 is configured to be movable along the guide rail 28 in the main scanning direction Y.

[0020] The ink head 32 is positioned above the support base 25. Here, the ink head 32 is positioned above the workpiece 5 supported by the support base 25. The ink head 32 ejects ink. Here, the ink head 32 ejects ink downward toward the workpiece 5 supported by the support base 25. The ink head 32 is mounted on the carriage 30. Here, the ink head 32 is mounted on the carriage 30 with its bottom surface exposed downwards and is supported by the carriage 30.

[0021] The number of ink heads 32 is not particularly limited. In this embodiment, there are two ink heads 32. Here, the ink heads 32 include a first ink head 32A and a second ink head 32B. The first ink head 32A and the second ink head 32B are arranged side by side in the main scanning direction Y. The first ink head 32A is located to the right of the second ink head 32B. However, the first ink head 32A may be located to the left of the second ink head 32B.

[0022] Figure 4 is a schematic diagram showing the configuration of the bottom surface of the ink head 32 and the light irradiation device 35. In this embodiment, as shown in Figure 4, the first ink head 32A and the second ink head 32B are arranged offset in the sub-scanning direction X, a so-called staggered arrangement. The positions of the first ink head 32A and the second ink head 32B are different in the sub-scanning direction X. Here, the first ink head 32A is positioned further back than the second ink head 32B. The positions of the first ink head 32A and the second ink head 32B do not overlap in the sub-scanning direction X, and the front end of the first ink head 32A is positioned further back than the rear end of the second ink head 32B. However, the positions of the first ink head 32A and the second ink head 32B in the sub-scanning direction X may partially overlap. Furthermore, the first ink head 32A and the second ink head 32B are not limited to a staggered arrangement, and their positions in the sub-scanning direction X may be aligned. In other words, the positions of the front end sub-scanning direction X in the first ink head 32A and the second ink head 32B may be the same, or the positions of the rear end sub-scanning direction X may be the same.

[0023] In this embodiment, the first ink head 32A ejects color ink. The color ink is used to print an image onto the substrate 5 during printing. In this embodiment, as shown in Figure 4, the first ink head 32A has a plurality of color nozzles 33A for ejecting color ink and a nozzle surface 35A on which the plurality of color nozzles 33A are formed. The nozzle surface 35A constitutes the bottom surface of the first ink head 32A. The plurality of color nozzles 33A are arranged in a line in the sub-scanning direction X. Here, a row of multiple color nozzles 33A arranged in the sub-scanning direction X is called a color nozzle row 34A. The number of color nozzle rows 34A is not particularly limited, but here there are four. The four color nozzle rows 34A are arranged in a line in the main scanning direction Y.

[0024] The color ink ejected by the first ink head 32A is color ink excluding at least metallic ink and primer ink. Here, the color ink is process color ink. The first ink head 32A ejects cyan ink, magenta ink, yellow ink, and black ink as process color ink. In this embodiment, the color nozzle 33A has a color nozzle 33Aa that ejects cyan ink, a color nozzle 33Ab that ejects magenta ink, a color nozzle 33Ac that ejects yellow ink, and a color nozzle 33Ad that ejects black ink. Each of the color nozzles 33Aa, 33Ab, 33Ac, and 33Ad is arranged in a plurality in the sub-scanning direction X. The color nozzle row 34A includes a cyan ink color nozzle row 34Aa composed of multiple color nozzles 33Aa, a magenta ink color nozzle row 34Ab composed of multiple color nozzles 33Ab, a yellow ink color nozzle row 34Ac composed of multiple color nozzles 33Ac, and a black ink color nozzle row 34Ad composed of multiple color nozzles 33Ad. The number of each color nozzle row 34Aa, 34Ab, 34Ac, and 34Ad is one, but there may be multiple.

[0025] The second ink head 32B ejects primer ink and metallic ink. Primer ink is an ink used as a base coat, and in this case, it is a primer ink for metallic ink used when printing over metallic ink. Metallic ink is an ink that contains metal powder such as aluminum.

[0026] As shown in Figure 4, the second ink head 32B has a plurality of primer nozzles 33Ba for ejecting primer ink, a plurality of metallic nozzles 33Bb for ejecting metallic ink, and a nozzle surface 35B on which the plurality of primer nozzles 33Ba and the plurality of metallic nozzles 33Bb are formed. The nozzle surface 35B constitutes the bottom surface of the second ink head 32B. The plurality of primer nozzles 33Ba are arranged in a line in the sub-scanning direction X. Here, a row of plurality of primer nozzles 33Ba arranged in the sub-scanning direction X is called a primer nozzle row 34Ba. The number of primer nozzle rows 34Ba is not particularly limited, but here there are two. Similarly, the plurality of metallic nozzles 33Bb are arranged in a line in the sub-scanning direction X. A row of plurality of metallic nozzles 33Bb arranged in the sub-scanning direction X is called a metallic nozzle row 34Bb. The number of metallic nozzle rows 34Bb is not particularly limited, but here there are two. In this embodiment, two primer nozzle rows 34Ba and two metallic nozzle rows 34Bb are arranged side by side in the main scanning direction Y.

[0027] In this embodiment, the ink ejected from the ink head 32 (here, color ink, primer ink, and metallic ink) is a photocurable ink whose drying is accelerated when exposed to light. The light irradiated onto the ink is, for example, ultraviolet light. Here, the ink ejected from the ink head 32 is an ultraviolet-curable ink whose curing is accelerated when exposed to ultraviolet light.

[0028] In this embodiment, the ink ejected from the ink head 32 is contained in an ink cartridge 45 shown in Figure 2. The ink cartridge 45 has a color cartridge 45A containing color ink, a primer cartridge 45Ba containing primer ink, and a metallic cartridge 45Bb containing metallic ink. The color cartridge 45A has a cartridge 45Aa containing cyan ink, a cartridge 45Ab containing magenta ink, a cartridge 45Ac containing yellow ink, and a cartridge 45Ad containing black ink. For example, a storage section 46 is provided on the front left side of the printer body 11. The ink cartridge 45 is housed in the storage section 46. The ink cartridge 45 is connected to one of the color nozzles 33A, primer nozzle 33Ba, or metallic nozzle 33Bb, which eject ink of the corresponding color, via an ink tube (not shown). The ink contained in the ink cartridge 45 is supplied to the ink head 32 through the ink tube.

[0029] The light irradiation device 35 is a device that irradiates light. In this embodiment, the light irradiation device 35 is a device that irradiates light onto the ink ejected from the ink head 32. More specifically, the light irradiation device 35 is configured to irradiate light onto the ink ejected onto the workpiece 5 supported by the support base 25. In this embodiment, as described above, the ink ejected from the ink head 32 is an ultraviolet-curable ink whose hardening is accelerated when irradiated with ultraviolet light, for example. Therefore, the light irradiation device 35 can be an ultraviolet irradiation device that irradiates ultraviolet light onto the ink ejected from the ink head 32.

[0030] As shown in Figure 2, the light irradiation device 35 is mounted on the carriage 30 and is configured to move in the main scanning direction Y together with the carriage 30 and the ink head 32. In this embodiment, there is one light irradiation device 35. The light irradiation device 35 is mounted on the left side of the carriage 30. However, the light irradiation device 35 may be mounted on the right side of the carriage 30. Also, there may be two or more light irradiation devices 35. One light irradiation device 35 may be mounted on both the left and right sides of the carriage 30.

[0031] As shown in Figure 4, the light irradiation device 35 has an irradiation body 36 and a plurality of light sources 37. The irradiation body 36 is, for example, a rectangular parallelepiped and hollow. In this embodiment, the light irradiation device 35 is sized such that a part of it overlaps with the position of the first ink head 32A in the sub-scanning direction X, and another part of it overlaps with the position of the second ink head 32B in the sub-scanning direction X. Therefore, the irradiation body 36 extends in the sub-scanning direction X such that a part of it overlaps with the position of the first ink head 32A in the sub-scanning direction X, and another part of it overlaps with the position of the second ink head 32B in the sub-scanning direction X. Here, the irradiation body 36 protrudes rearward from the first ink head 32A and forward from the second ink head 32B. That is, the front end of the irradiation body 36 is located in front of the front end of the second ink head 32B. The rear end of the irradiation body 36 is located rearward from the rear end of the first ink head 32A.

[0032] In this embodiment, the irradiation body 36 is divided into multiple irradiation regions in the sub-scanning direction X. The multiple irradiation regions are regions obtained by dividing the irradiation body 36 at equal intervals, but they do not have to be regions divided at equal intervals. Here, the irradiation body 36 has as irradiation regions a first irradiation region AR11, a second irradiation region AR12, a third irradiation region AR13, and a fourth irradiation region AR14. The first to fourth irradiation regions AR14 are arranged side by side in the sub-scanning direction X. The first irradiation region AR11 is the region located on the front side of the irradiation body 36. The second irradiation region AR12 is located behind the first irradiation region AR11 and is continuous with the first irradiation region AR11. The third irradiation region AR13 is located behind the second irradiation region AR12 and is continuous with the second irradiation region AR12. The fourth irradiation region AR14 is located behind the third irradiation region AR13 and is continuous with the third irradiation region AR13. Here, the irradiation regions are arranged in the order of the first irradiation region AR11, the second irradiation region AR12, the third irradiation region AR13, and the fourth irradiation region AR14, from front to back in the sub-scanning direction X. The lengths of the first irradiation region AR11 to the fourth irradiation region AR14 are the same in the sub-scanning direction X, but at least some of the lengths of the sub-scanning direction X may differ.

[0033] In this embodiment, the first irradiation area AR11 and the second irradiation area AR12 of the irradiation body 36 overlap with the position of the second ink head 32B in the sub-scanning direction X, or protrude forward of the second ink head 32B. The first irradiation area AR11 and the second irradiation area AR12 are located forward of the first ink head 32A. Specifically, the front part of the first irradiation area AR11 is located forward of the second ink head 32B. The rear part of the first irradiation area AR11 overlaps with the position of the second ink head 32B in the sub-scanning direction X. The second irradiation area AR12 overlaps with the position of the second ink head 32B in the sub-scanning direction X. The third irradiation area AR13 and the fourth irradiation area AR14 of the irradiation body 36 overlap with the position of the first ink head 32A in the sub-scanning direction X, or protrude rearward of the first ink head 32A. The third irradiation area AR13 and the fourth irradiation area AR14 are located rearward of the second ink head 32B. More specifically, the third irradiation area AR13 overlaps with the position of the first ink head 32A in the sub-scanning direction X. The front part of the fourth irradiation area AR14 overlaps with the position of the first ink head 32A in the sub-scanning direction X. The rear part of the fourth irradiation area AR14 is located behind the first ink head 32A.

[0034] As shown in Figure 4, an irradiation port 38 is formed on the bottom surface of the irradiation body 36. The irradiation port 38 opens downwards. The shape of the irradiation port 38 is rectangular, but is not particularly limited. The irradiation port 38 is formed in the irradiation body 36 so as to extend across the first irradiation region AR11 to the fourth irradiation region AR14. The length of the irradiation port 38 in the sub-scanning direction X in each irradiation region AR11 to AR14 may be the same, or at least a part of it may be different.

[0035] The light source 37 emits light (in this case, ultraviolet light). In this embodiment, multiple light sources 37 are arranged inside the irradiation body 36. The multiple light sources 37 are arranged along the sub-scanning direction X. The multiple light sources 37 are arranged at equal intervals, but the distances between the light sources 37 may differ. Here, the positions of the multiple light sources 37 in the main scanning direction Y are the same, but may differ. At least one light source 37 is arranged in each irradiation area AR11 to AR14 of the irradiation body 36. The number of light sources 37 arranged in each irradiation area AR11 to AR14 is not particularly limited and may be the same or different. In this embodiment, for the sake of explanation, three light sources 37 are arranged in each irradiation area AR11 to AR14, but in reality, many more light sources 37 may be arranged in each irradiation area AR11 to AR14.

[0036] The light source 37 can be switched on and off. In this embodiment, multiple light sources 37 can be switched on and off independently. The type of light source 37 is not particularly limited. Here, the light source 37 is a light-emitting diode (in other words, an LED). Because the light source 37 can be switched on and off independently, the light irradiation device 35 can turn the light (in other words, the light source 37) on or off independently for each irradiation area AR11 to AR14. In addition, in this embodiment, the light source 37 is configured to allow adjustment of its illuminance (in other words, peak illuminance).

[0037] As shown in Figure 2, the printer 10 includes a first moving mechanism 51 that moves the carriage 30, ink head 32, and light irradiation device 35 relative to the support base 25 (more specifically, the workpiece 5 supported on the support base 25) in the main scanning direction Y, and a second moving mechanism 52 that moves the workpiece 5 supported on the support base 25 relative to the carriage 30, ink head 32, and light irradiation device 35 in the sub-scanning direction X. Although a detailed explanation of the configuration is omitted, the printer 10 also includes a lifting mechanism 53 that raises and lowers the support base 25.

[0038] The first moving mechanism 51 moves the carriage 30, ink head 32, and light irradiation device 35 in the main scanning direction Y. The configuration of the first moving mechanism 51 is not particularly limited. The first moving mechanism 51, although not shown in the figures, includes, for example, left and right pulleys, a belt, and a scan motor. The left pulley is provided around the left end of the guide rail 28, and the right pulley is provided around the right end of the guide rail 28. The belt is, for example, an endless belt, which is wrapped around the left and right pulleys. The carriage 30 is attached and fixed to the belt. The scan motor is connected to one of the left and right pulleys. When the scan motor is driven, the pulley rotates, and the belt travels between the left and right pulleys. As a result, the ink head 32 and light irradiation device 35 move along the guide rail 28 in the main scanning direction Y, together with the carriage 30.

[0039] The second moving mechanism 52 moves the support base 25 in the sub-scanning direction X, thereby moving the workpiece 5 supported on the support base 25 in the sub-scanning direction X. The configuration of the second moving mechanism 52 is not particularly limited. Here, although not shown in the figures, the second moving mechanism 52 includes a support base carriage that supports the support base 25, and a pair of left and right slide rails that slidably support the support base carriage and extend in the sub-scanning direction X. Although not shown in the figures, the second moving mechanism 52 further includes a pair of front and rear slide pulleys provided in front of and behind the slide rails, and a slide belt wrapped around the pair of front and rear slide pulleys. The support base carriage is fixed to this slide belt. A feed motor is connected to one of the front and rear slide pulleys. Here, when the feed motor is driven and the slide belt moves, the support base 25 moves in the sub-scanning direction X together with the support base carriage. As a result, the workpiece 5 supported on the support base 25 also moves in the sub-scanning direction X.

[0040] As shown in Figure 2, the printer 10 is equipped with a control device 60. The control device 60 is a device that performs control related to printing. The configuration of the control device 60 is not particularly limited. The control device 60 is, for example, a microcomputer. The hardware configuration of the microcomputer is not particularly limited. The control device 60 includes, for example, an interface (I / F) for receiving print data from an external device such as a host computer, a central processing unit (CPU) that executes instructions for the control program, a ROM (Read Only Memory) that stores the program executed by the CPU, a RAM (Random Access Memory) used as a working area for expanding the program, and a memory that stores the program and various data. The control device 60 is located inside the printer body 11. However, the control device 60 may be implemented as a computer or the like installed outside the printer body 11. In this case, the control device 60 is preferably connected to the control board (not shown) of the printer 10 via wired or wireless communication.

[0041] In this embodiment, as shown in Figure 3, the control device 60 is communicatively connected to the operation panel 20 (specifically the display screen 21 and operation keys 22), the ink head 32 (specifically the first ink head 32A and the second ink head 32B), the light irradiation device 35 (specifically the light source 37), the first moving mechanism 51, the second moving mechanism 52, and the lifting mechanism 53. The control device 60 controls the operation panel 20, the ink head 32, the light irradiation device 35, the first moving mechanism 51, the second moving mechanism 52, and the lifting mechanism 53.

[0042] The configuration of the printer 10 according to this embodiment has been described above. In this embodiment, as shown in Figure 4, overprinting can be performed on the substrate 5 using color ink ejected by the first ink head 32A, primer ink ejected by the second ink head 32B, and metallic ink. Figure 5 is a schematic cross-sectional view showing the state in which a primer layer L11, a metallic layer L12, and a color printing layer L13 have been formed on the substrate 5. In this embodiment, as shown in Figure 5, the primer layer L11, metallic layer L12, and color printing layer L13 are sequentially formed on the substrate 5 by printing with the printer 10. The primer layer L11 is formed directly on the substrate 5. The metallic layer L12 is formed directly on the primer layer L11. The color printing layer L13 is formed directly on the metallic layer L12.

[0043] The primer layer L11 is a layer formed by primer ink ejected from the primer nozzle 33Ba (see Figure 4), which constitutes the primer nozzle row 34Ba of the second ink head 32B. The primer ink is ejected from the primer nozzle 33Ba toward the substrate 5, forming the primer layer L11 on the substrate 5. The metallic layer L12 is a layer formed by metallic ink ejected from the metallic nozzle 33Bb (see Figure 4), which constitutes the metallic nozzle row 34Bb of the second ink head 32B. The metallic ink is ejected from the metallic nozzle 33Bb toward the primer layer L11 on the substrate 5, forming the metallic layer L12 on the primer layer L11. The color printing layer L13 is a layer formed by color ink (in this case, process color ink) ejected from the first ink head 32A in Figure 4. Color ink is ejected from the color nozzle 33A of the first ink head 32A toward the metallic layer L12 of the substrate 5, thereby forming a color printing layer L13 on top of the metallic layer L12.

[0044] In this embodiment, the metallic layer L12 and the color printing layer L13 are formed by printing based on predetermined print data (not shown). Print data refers to raster data or bitmap data obtained by processing a print image to be printed on the substrate 5 with a RIP (Raster Image Processor). The print data is stored in advance, for example, in the storage unit 61 (see Figure 3) of the control device 60, which will be described later. This print data indicates the positions where the metallic layer L12 will be formed and the positions where the color printing layer L13 will be formed. The print data also indicates which color ink (here, color ink and metallic ink) will be ejected at which positions. Therefore, based on this print data, the control device 60 of the printer 10 ejects metallic ink at the positions on the substrate 5 corresponding to the positions where the metallic layer L12 will be formed, thereby forming the metallic layer L12 on the substrate 5. Then, based on the print data, it ejects color ink (e.g., process color ink) at the positions on the substrate 5 corresponding to the positions where the color printing layer L13 will be formed, thereby forming the color printing layer L13 on the substrate 5.

[0045] By the way, when ink is ejected onto the substrate 5 to form layers such as the primer layer L11, metallic layer L12, and color printing layer L13, the layers may be partially cured or fully cured. Here, partially cured or fully cured layers refer to the partially cured or fully cured ink that forms the layers. Here, the operation controlled by the printer 10 when partially curing a layer is called pinning. The operation controlled by the printer 10 when fully curing a layer is called curing. This pinning and curing is performed by irradiating the layers formed by the ejection of ink onto the substrate 5 with light from the light irradiation device 35.

[0046] In this embodiment, the operation to be performed, either pinning or curing, is determined according to the illuminance (here, peak illuminance) of the light emitted from the light irradiation device 35. Here, the peak illuminance of the light emitted from the light irradiation device 35 when pinning is being performed is called the pinning peak illuminance L21 (see Figure 8). On the other hand, the peak illuminance of the light emitted from the light irradiation device 35 when curing is being performed is called the curing peak illuminance L22 (see Figure 8). Here, the curing peak illuminance L22 is higher than the pinning peak illuminance L21.

[0047] However, as shown in Figure 5, when a metallic layer L12 and a color printing layer L13 are laminated and printed on the substrate 5 in that order, the brightness of the color ink forming the color printing layer L13 (hereinafter also referred to as the brightness of the color printing layer L13 or the brightness of the color ink) was sometimes not sufficiently obtained.

[0048] Therefore, the inventors of the present invention investigated various reasons why the brightness of the color ink forming the color printing layer L13 could not be obtained sufficiently. For example, conventionally, when a color printing layer L13 was formed on the metallic layer L12 of the substrate 5, curing was immediately performed on the color printing layer L13 to immediately and completely harden the color ink forming the color printing layer L13. As a result of various investigations, the inventors of the present invention found that by forming the color printing layer L13 on the metallic layer L12 and immediately curing the color ink on the color printing layer L13 to completely harden the color ink, it was not possible to obtain sufficient brightness of the color printing layer L13. Furthermore, the applicants of the present invention found that when a color printing layer L13 is formed on the metallic layer L12, the brightness of the color printing layer L13 can be sufficiently ensured by first performing pinning on the color printing layer L13 and then performing curing after the pinning. Furthermore, the inventors of the present invention have found that when performing pinning on the color printing layer L13, the brightness of the color printing layer L13 can be further ensured by adjusting the peak illuminance of the light irradiated from the light irradiation device 35 (in other words, the integrated light amount on the color printing layer L13), adjusting the amount of color ink forming the color printing layer L13, and adjusting the surface tension of the color ink.

[0049] Next, we will describe the printing procedure for ensuring the brightness of the color printing layer L13 when printing with the printer 10 according to this embodiment. Here, we will first describe the outline of the printing procedure.

[0050] FIG. 6 is a flowchart showing a printing procedure. In the present embodiment, as shown in FIG. 6, after forming a primer layer L11 on the printed object 5 with primer ink in step S101, curing is performed on the primer layer L11 in step S102. Pinning is not performed on the primer layer L11. Next, after forming a metallic layer L12 on the primer layer L11 of the printed object 5 with metallic ink in step S103, pinning in step S104 is performed, and curing in step S105 is performed after pinning. Then, after forming a color printing layer L13 on the metallic layer L12 of the printed object 5 with color ink in step S106, pinning in step S107 is performed, and curing in step S108 is performed after pinning.

[0051] In the present embodiment, the ink amount of the color ink forming the color printing layer L13 is 2.6 g / m 2 ~12.8 g / m 2 Here, the ink amount is set according to the color of the color ink forming the color printing layer L13. In the present embodiment, the color printing layer L13 is formed by cyan ink, magenta ink, yellow ink, and black ink included in the process color ink ejected from the first ink head 32A. The ink amount of the cyan ink forming the color printing layer L13 is 2.6 g / m 2 ~12.8 g / m 2 Here, the ink amount of the magenta ink forming the color printing layer L13 is 2.6 g / m 2 ~12.8 g / m 2 Here, the ink amount of the yellow ink forming the color printing layer L13 is 2.6 g / m 2 ~5.1 g / m 2 Here, the ink amount of the black ink forming the color printing layer L13 is 2.6 g / m 2 ~5.1 g / m 2 Here.

[0052] In this embodiment, the surface tension of the color ink forming the color printing layer L13 is 22 mN / m to 31 mN / m, preferably 22 mN / m to 25 mN / m.

[0053] As described above, after a color printing layer L13 is formed on the metallic layer L12 formed on the substrate 5 using color ink, pinning and curing are performed sequentially on the color printing layer L13. Here, the pinning peak illuminance L21 of the light irradiation device 35 (in other words, the light source 37) during pinning of the color printing layer L13 is 0.025 W / cm². 2 Larger. The integrated light intensity from the light irradiation device 35 to the color printing layer L13 during pinning is 40 mJ / cm². 2 ~200 mJ / cm 2 Furthermore, the curing peak illuminance L22 of the light irradiation device 35 (in other words, the light source 37) during curing of the color printing layer L13 is 1.0 W / cm². 2 ~2.5W / cm 2 The cumulative amount of light from the light irradiation device 35 to the color printing layer L13 during curing is 1000 mJ / cm². 2 ~2500 mJ / cm 2 That is the case.

[0054] In this embodiment, the amount of primer ink used to form the primer layer L11 is 17 g / m². 2 ~25g / m 2 The amount of primer ink forming the primer layer L11 is greater than the amount of color ink forming the color printing layer L13. The surface tension of the primer ink forming the primer layer L11 is 20 mN / m to 35 mN / m. The surface tension of the primer ink may be greater than or less than the surface tension of the color ink. Here, as described above, after the primer layer L11 is formed on the substrate 5, curing is performed on the primer layer L11. The curing peak illuminance L22 of the light irradiation device 35 during curing of the primer layer L11 is 1.0 W / cm². 2 ~2.5W / cm2 The curing peak illuminance L22 in the primer layer L11 and the color printing layer L13 are approximately the same. However, the curing peak illuminance L22 of the primer layer L11 may be higher or lower than that of the color printing layer L13. The integrated light amount from the light irradiation device 35 to the primer layer L11 during curing is 700 mJ / cm². 2 ~2,750 mJ / cm² 2 The cumulative light intensity during curing is approximately the same for both the primer layer L11 and the color printing layer L13. However, the cumulative light intensity during curing for the primer layer L11 may be higher or lower than that for the color printing layer L13.

[0055] In this embodiment, the amount of metallic ink used to form the metallic layer L12 is 9.5 g / m². 2 ~11.0g / m 2 The metallic ink forming the metallic layer L12 is used in smaller quantities than the primer ink forming the primer layer L11. The surface tension of the metallic ink forming the metallic layer L12 is 20 mN / m to 35 mN / m. The surface tension of the metallic ink may be greater than or less than the surface tension of the color ink and primer ink. Here, as described above, after the metallic layer L12 is formed on the primer layer L11 formed on the substrate 5, pinning and curing are performed sequentially on the metallic layer L12. Here, the pinning peak illuminance L21 of the light irradiation device 35 during pinning of the metallic layer L12 is 0.100 W / cm². 2 ~0.125W / cm 2 The pinning peak illuminance L21 in the metallic layer L12 is higher than the pinning peak illuminance L21 in the color printing layer L13. The integrated light amount from the light irradiation device 35 to the metallic layer L12 during pinning is 70 mJ / cm². 2 ~250 mJ / cm 2In the metallic layer L12, the integrated light intensity during pinning may be greater than or less than the integrated light intensity during pinning of the color printing layer L13. Furthermore, the curing peak illuminance L22 of the light irradiation device 35 during curing of the metallic layer L12 is 1.0 W / cm². 2 ~2.5W / cm 2 The curing peak illuminance L22 in the metallic layer L12 may be higher or lower than the curing peak illuminance L22 in the primer layer L11 and the color printing layer L13. The integrated light amount from the light irradiation device 35 to the metallic layer L12 during curing of the metallic layer L12 is 1,000 mJ / cm². 2 ~2,500 mJ / cm² 2 In the metallic layer L12, the accumulated light during curing may be greater than or less than the accumulated light during curing of the primer layer L11 and the color printing layer L13.

[0056] In this embodiment, the pinning peak illuminance L21 when performing pinning on the metallic layer L12 (hereinafter also referred to as the pinning peak illuminance L21 of the metallic layer L12) is different from the pinning peak illuminance L21 when performing pinning on the color printing layer L13 (hereinafter also referred to as the pinning peak illuminance L21 of the color printing layer L13). Here, the pinning peak illuminance L21 of the metallic layer L12 may be higher or lower than the pinning peak illuminance L21 of the color printing layer L13. Note that "different peak illuminances" here means that the difference in peak illuminances is 0.05 W / cm². 2 The above refers to the situation described above. For example, when the ratio of the peak illuminance of a ping with a lower peak illuminance to that of a ping with a higher peak illuminance is between 20% and 50%, it is said that the "peak illuminances are different."

[0057] Furthermore, in this embodiment, the curing peak illuminance L22 when curing is performed on the primer layer L11 (hereinafter also referred to as the curing peak illuminance L22 of the primer layer L11) is different from the curing peak illuminance L22 when curing is performed on the metallic layer L12 (hereinafter also referred to as the curing peak illuminance L22 of the metallic layer L12) and the curing peak illuminance L22 when curing is performed on the color printing layer L13 (hereinafter also referred to as the curing peak illuminance L22 of the color printing layer L13). Here, the curing peak illuminance L22 of the color printing layer L13 may be higher or lower than the curing peak illuminance L22 of the metallic layer L12. The curing peak illuminance L22 of the color printing layer L13 may be higher or lower than the curing peak illuminance L22 of the primer layer L11. Furthermore, the curing peak illuminance L22 of the metallic layer L12 may be higher or lower than the curing peak illuminance L22 of the primer layer L11.

[0058] Next, the control procedure for printing on the material to be printed 5 will be explained in accordance with the flowchart in Figure 6. In this embodiment, as shown in Figure 3, the control device 60 of the printer 10 includes a storage unit 61, a primer printing unit 62, a metallic printing unit 63, a color printing unit 64, a pinning control unit 65, and a curing control unit 66. Each of the units 61 to 66 of the control device 60 may be implemented by one or more processors or by circuits.

[0059] First, in step S101 of Figure 6, the primer printing unit 62 of Figure 3 forms a primer layer L11 (see Figure 5) on the workpiece 5 supported on the support base 25. Figure 7 is a schematic plan view showing the state of the light irradiation device 35 when curing is performed on the primer layer L11. Note that in Figures 7 to 9, the irradiation areas AR11 to AR14 that are turned off in the light irradiation device 35 are indicated by an "x". As shown in Figure 7, the primer printing unit 62 ejects primer ink onto the workpiece 5 from the primer nozzle 33Ba of the primer nozzle row 34Ba of the second ink head 32B. In this embodiment, the primer layer L11 is formed on the workpiece 5 while moving the workpiece 5 supported on the support base 25 to the front side in the sub-scanning direction X. Here, the primer printing unit 62 controls the first moving mechanism 51 (see Figure 3) to move the carriage 30 in the main scanning direction Y. When the carriage 30 is moving, for example, from left to right in the main scanning direction Y, the primer printing unit 62 can form a primer layer L11 directly on the workpiece 5 by ejecting primer ink from the primer nozzle 33Ba. After moving the carriage 30 in the main scanning direction Y in this manner, the primer printing unit 62 controls the second moving mechanism 52 (see Figure 3) to move the workpiece 5, supported by the support base 25, forward in the sub-scanning direction X by a predetermined distance. Subsequently, while moving the carriage 30 in the main scanning direction Y, the primer printing unit 62 can form the next primer layer L11 on the workpiece 5 by ejecting primer ink from the primer nozzle 33Ba. In this way, by repeatedly ejecting primer ink while the carriage 30 is moving in the main scanning direction Y and moving the workpiece 5 forward in the sub-scanning direction X, a primer layer L11 can be formed on the workpiece 5 as shown in Figure 5.

[0060] Next, in step S102 of Figure 6, the curing control unit 66 of Figure 3 performs curing on the primer layer L11 formed on the workpiece 5 by the primer printing unit 62. Here, pinning is not performed on the primer layer L11; only curing is performed. In this embodiment, the curing control unit 66 performs curing on the portion of the primer layer L11 located directly below the light irradiation device 35 when the carriage 30 is moving in the main scanning direction Y by the primer printing unit 62. Here, as shown in Figure 7, when the curing control unit 66 performs curing on the primer layer L11, it lights up the first irradiation area AR11 and the second irradiation area AR12 of the light irradiation device 35 (more specifically, it lights up the light sources 37 located in the first irradiation area AR11 and the second irradiation area AR12). At this time, the peak illuminance of light in the first irradiation area AR11 and the second irradiation area AR12 is the curing peak illuminance L22 of the primer layer L11. During the formation of the primer layer L11, the third irradiation area AR13 and the fourth irradiation area AR14 of the light irradiation device 35 are turned off. Here, as the carriage 30 moves from left to right in the main scanning direction Y, immediately after the primer ink is ejected onto the substrate 5 and the primer layer L11 is formed on the substrate 5, the primer layer L11 is irradiated with light from the first irradiation area AR11 and the second irradiation area AR12 of the light irradiation device 35. Therefore, the portion of the primer layer L11 that has been irradiated with light by curing is completely cured. In this manner, curing is performed on the primer layer L11 formed on the substrate 5.

[0061] Next, in step S103 of Figure 6, the metallic printing unit 63 in Figure 3 is the workpiece 5 supported on the support base 25, and a metallic layer L12 (see Figure 5) is formed on the primer layer L11 formed on the workpiece 5. Figure 8 is a schematic plan view showing the state of the light irradiation device 35 when pinning and curing are performed on the metallic layer L12. Here, as shown in Figure 8, the metallic printing unit 63 ejects metallic ink onto the primer layer L11 from the metallic nozzles 33Bb of the metallic nozzle row 34Bb of the second ink head 32B. Here, when the primer layer L11 is formed on the workpiece 5, the primer layer L11 formed on the workpiece 5 is located in front of the carriage 30 in the sub-scanning direction X. Therefore, when forming the metallic layer L12, the workpiece 5 supported on the support base 25 is moved to the rear side in the sub-scanning direction X while the metallic layer L12 is formed on the primer layer L11 of the workpiece 5. The metallic printing unit 63 controls the first moving mechanism 51 to move the carriage 30 in the main scanning direction Y. Then, when the carriage 30 is moving, for example, from left to right in the main scanning direction Y, the metallic printing unit 63 can form a metallic layer L12 directly on the primer layer L11 by ejecting metallic ink from the metallic nozzle 33Bb. After moving the carriage 30 in the main scanning direction Y in this way, the metallic printing unit 63 controls the second moving mechanism 52 to move the workpiece 5 supported on the support base 25 to the rear side in the sub-scanning direction X by a predetermined distance. Subsequently, while moving the carriage 30 in the main scanning direction Y, the metallic printing unit 63 can form the next metallic layer L12 on the primer layer L11 of the workpiece 5 by ejecting metallic ink from the metallic nozzle 33Bb. In this way, by repeatedly ejecting metallic ink while the carriage 30 moves in the main scanning direction Y and moving the substrate 5 backward in the sub-scanning direction X, a metallic layer L12 can be formed on the primer layer L11 formed on the substrate 5, as shown in Figure 5.

[0062] Next, in step S104 of Figure 6, the pinning control unit 65 of Figure 3 performs pinning on the metallic layer L12 formed on the workpiece 5 by the metallic printing unit 63. The pinning control unit 65 performs pinning on the portion of the metallic layer L12 located directly below the light irradiation device 35 when the carriage 30 is moving in the main scanning direction Y by the metallic printing unit 63. Here, as shown in Figure 8, when the pinning control unit 65 performs pinning on the metallic layer L12, it lights up the first irradiation area AR11 and the second irradiation area AR12 of the light irradiation device 35 (more specifically, it lights up the light sources 37 located in the first irradiation area AR11 and the second irradiation area AR12). The peak illuminance of light in the first irradiation area AR11 and the second irradiation area AR12 at this time is the pinning peak illuminance L21 of the metallic layer L12. As a result, when the carriage 30 is moving from left to right in the main scanning direction Y, metallic ink is ejected onto the substrate 5 and immediately after the metallic layer L12 is formed on the primer layer L11 of the substrate 5, light from the first irradiation area AR11 and the second irradiation area AR12 of the light irradiation device 35 is irradiated onto the metallic layer L12. Therefore, the portion of the metallic layer L12 that is irradiated with light by pinning becomes semi-cured. In this manner, pinning is performed on the metallic layer L12 formed on the primer layer L11 of the substrate 5.

[0063] Next, in step S105 of Figure 6, the curing control unit 66 in Figure 3 performs curing on the portion of the metallic layer L12 that has been pinned by the pinning control unit 65. Here, the curing control unit 66 performs curing on the portion of the metallic layer L12 located directly below the light irradiation device 35 when the carriage 30 moves in the main scanning direction Y by the metallic printing unit 63, and the workpiece 5 supported on the support base 25 moves to the rear in the sub-scanning direction X. Here, as shown in Figure 8, when the curing control unit 66 performs curing on the metallic layer L12, it lights up the fourth irradiation area AR14 of the light irradiation device 35 (specifically, it lights up the light source 37 located in the fourth irradiation area AR14). The peak illuminance of light in the fourth irradiation area AR14 at this time is the curing peak illuminance L22 of the metallic layer L12. Note that the third irradiation area AR13 of the light irradiation device 35 is turned off when the metallic layer L12 is formed. Here, the substrate 5 moves relative to the carriage 30 in the main scanning direction Y and the sub-scanning direction X, and light is irradiated from the fourth irradiation area AR14 to the metallic layer L12 that has moved directly below the fourth irradiation area AR14, from which pinning has been performed. As a result, the portion of the metallic layer L12 that has been irradiated with light by curing is completely cured. In this way, curing is performed on the metallic layer L12 formed on the primer layer L11 of the substrate 5.

[0064] Next, in step S106 of Figure 6, the color printing unit 64 in Figure 3 is the workpiece 5 supported on the support base 25, and a color printing layer L13 (see Figure 5) is formed on the metallic layer L12 formed on the workpiece 5. Figure 9 is a schematic plan view showing the state of the light irradiation device 35 when pinning and curing are performed on the color printing layer L13. Here, as shown in Figure 9, the color printing unit 64 ejects color ink from the color nozzles 33A of the color nozzle row 34A of the first ink head 32A onto the metallic layer L12. Here, when the metallic layer L12 is formed on the workpiece 5, the metallic layer L12 formed on the workpiece 5 is located behind the carriage 30 in the sub-scanning direction X. Therefore, when forming the color printing layer L13, the workpiece 5 supported on the support base 25 is moved forward in the sub-scanning direction X while the color printing layer L13 is formed on the metallic layer L12 of the workpiece 5. Here, the color printing unit 64 controls the first moving mechanism 51 to move the carriage 30 in the main scanning direction Y. Then, when the carriage 30 is moving, for example, from left to right in the main scanning direction Y, the color printing unit 64 can form a color printing layer L13 directly on the metallic layer L12 by ejecting color ink from the color nozzle 33A. After moving the carriage 30 in the main scanning direction Y in this way, the color printing unit 64 controls the second moving mechanism 52 to move the workpiece 5 supported on the support base 25 forward in the sub-scanning direction X by a predetermined distance. Subsequently, while moving the carriage 30 in the main scanning direction Y, the color printing unit 64 can form the next color printing layer L13 on the metallic layer L12 of the workpiece 5 by ejecting color ink from the color nozzle 33A. In this way, by repeatedly ejecting color ink while the carriage 30 moves in the main scanning direction Y and moving the substrate 5 forward in the sub-scanning direction X, a color printing layer L13 can be formed on the metallic layer L12 formed on the substrate 5, as shown in Figure 5. Note that a portion of the color printing layer L13 may not be formed on the metallic layer L12, but directly on the primer layer L11.Furthermore, a portion of the metallic layer L12 may not have the color printing layer L13 formed on it and may be exposed to the upper surface.

[0065] Next, in step S107 of Figure 6, the pinning control unit 65 of Figure 3 performs pinning on the color printing layer L13 formed on the workpiece 5 by the color printing unit 64. The pinning control unit 65 performs pinning on the portion of the color printing layer L13 located directly below the light irradiation device 35 when the carriage 30 is moving in the main scanning direction Y by the color printing unit 64. Here, as shown in Figure 9, when the pinning control unit 65 performs pinning on the color printing layer L13, it lights up the third irradiation area AR13 and the fourth irradiation area AR14 of the light irradiation device 35 (more specifically, it lights up the light sources 37 located in the third irradiation area AR13 and the fourth irradiation area AR14). At this time, the peak illuminance of light in the third irradiation area AR13 and the fourth irradiation area AR14 is the pinning peak illuminance L21 of the color printing layer L13. As a result, when the carriage 30 moves from left to right in the main scanning direction Y, the color ink is ejected onto the substrate 5, and immediately after the color printing layer L13 is formed on the metallic layer L12 of the substrate 5, light from the third irradiation area AR13 and the fourth irradiation area AR14 of the light irradiation device 35 is irradiated onto the color printing layer L13. Therefore, the portion of the color printing layer L13 that is irradiated with light by pinning becomes semi-cured. In this manner, pinning is performed on the color printing layer L13 formed on the metallic layer L12 of the substrate 5.

[0066] Next, in step S108 of Figure 6, the curing control unit 66 of Figure 3 performs curing on the portion of the color printing layer L13 that has been pinned by the pinning control unit 65. Here, the curing control unit 66 performs curing on the portion of the color printing layer L13 located directly below the light irradiation device 35 when the carriage 30 is moving in the main scanning direction Y by the color printing unit 64, and the workpiece 5 supported on the support base 25 is moving forward in the sub-scanning direction X. Here, as shown in Figure 9, when the curing control unit 66 performs curing on the color printing layer L13, it lights up the first irradiation area AR11 of the light irradiation device 35 (more specifically, it lights up the light source 37 located in the first irradiation area AR11). The peak illuminance of the light in the first irradiation area AR11 at this time is the curing peak illuminance L22 of the color printing layer L13. Note that the second irradiation area AR12 of the light irradiation device 35 is turned off when the color printing layer L13 is formed. Here, the substrate 5 moves relative to the carriage 30 in the main scanning direction Y and the sub-scanning direction X, and light is irradiated from the first irradiation area AR11 to the color printing layer L13 that has moved directly below the first irradiation area AR11, from which pinning has been performed. As a result, the portion of the color printing layer L13 that has been irradiated with light by curing is completely cured. In this way, curing is performed on the color printing layer L13 formed on the metallic layer L12 of the substrate 5.

[0067] The following describes examples relating to the present invention, but it is not intended to limit the examples to those shown.

[0068] Here, first, printing was performed on the substrates for Examples 1 to 5 using printer 10. For the substrates for Examples 1 to 5, a primer layer was formed on top of the substrate, a metallic layer was formed on top of the primer layer, and a color printing layer was formed on top of the metallic layer. In Examples 1 to 5, the printing conditions for forming the primer layer and the metallic layer were the same. Here, in Examples 1 to 5, the primer layer was formed by ejecting primer ink onto the substrate. After that, curing was performed on the primer layer. The curing peak illuminance of the primer layer at this time was 1.0 W / cm². 2 Next, in Examples 1 to 5, a metallic layer was formed on the primer layer by ejecting metallic ink onto the primer layer. Subsequently, pinning and curing were performed on the metallic layer using the same procedure as, for example, steps S104 and S105 in Figure 6. At this time, the pinning peak illuminance of the metallic layer was 0.1 W / cm². 2 The curing peak illuminance of the metallic layer is 1.0 W / cm². 2 That is the case.

[0069] In Examples 1 through 5, some of the printing conditions for forming the color printing layer differ. The printing conditions for Examples 1 through 5 are shown in Table 1 below.

[0070] [Table 1]

[0071] In Examples 1 to 5, a color print layer was formed on top of the metallic layer by ejecting color ink onto the metallic layer. Here, as shown in Table 1, cyan ink, magenta ink, yellow ink, and black ink were used as color inks. In Examples 1 to 5, in order to measure the 60° gloss of each color ink as described later, the color print layer was formed by ejecting cyan ink, magenta ink, yellow ink, and black ink to separate areas. The amount of cyan ink, magenta ink, yellow ink, and black ink, as well as the surface tension of the color inks in Examples 1 to 5, are shown in Table 1.

[0072] In Examples 1 to 4, pinning and curing were performed sequentially on the color printing layer. The pinning peak illuminance of the color printing layer differed in Examples 1 to 4, as shown in Table 1. In Example 5, only curing was performed on the color printing layer without pinning. The curing peak illuminance of the color printing layer was the same in Examples 1 to 5, at 1.0 W / cm². 2 (See Table 1).

[0073] For the printed materials of Examples 1 to 5, printed as described above, the 60° gloss of cyan, magenta, yellow, and black inks was measured using a gloss meter with model number PG-IIM manufactured by Nippon Denshoku Industries, Ltd. The results are shown in Table 2 below. In addition, the color development of the color inks in the color printing layer, as well as the wrinkles and bleeding of the printed material, were visually judged for the printed materials of Examples 1 to 5. The results are shown in Table 2 below. When the experimenter visually checked the color development of the color inks, if the result was judged to be good, the result was marked with ○, and when the result was judged to be poor, the result was marked with ×. When the experimenter visually checked the printed material and determined that there were no wrinkles or bleeding, the result was marked with "None". On the other hand, when the experimenter visually checked the printed material and determined that there were wrinkles or bleeding, the result was marked with "Yes".

[0074] [Table 2]

[0075] As shown in Tables 1 and 2 above, when curing was performed immediately and fully cured without pinning the color printing layer, as in Example 5, the 60° gloss was low and the brightness of the color ink was not obtained. On the other hand, when curing was performed after pinning the color printing layer, as in Examples 1 to 4, the 60° gloss was increased and the brightness of the color ink was obtained. Also, as in Example 1, when the pinning peak illuminance when performing pinning on the color printing layer was 0.025 W / cm² 2 The following results showed wrinkles and smudges in the printed material. However, as in Examples 2 to 4, when performing pinning on the color printed layer, the pinning peak illuminance was set to 0.025 W / cm². 2 When the setting was increased, the result was that there were no wrinkles or smudges in the printed material. For example, when the pinning peak illuminance was low (e.g., 0.025 W / cm²). 2 In the following cases, the color ink may not cure sufficiently, causing the ink to move to align with the dots, resulting in bleeding of the printed material. Furthermore, if the color ink is not sufficiently cured during pinning and curing is performed with a large amount of ink, only the surface of the color ink will cure, leaving the inside of the coating uncured. This creates a volume difference and causes curing shrinkage. As a result, wrinkles may occur in the printed material.

[0076] As described above, in this embodiment, as shown in Figure 2, the printer 10 includes a support base 25 for supporting the workpiece 5, an ink head 32 for ejecting ink toward the workpiece 5 supported on the support base 25, a light irradiation device 35 for irradiating light onto the workpiece 5 supported on the support base 25, and a control device 60. As shown in Figure 4, the ink head 32 includes a color nozzle row 34A having color nozzles 33A for ejecting color ink, and a metallic nozzle row 34Bb having metallic nozzles 33Bb for ejecting metallic ink. As shown in Figure 3, the control device 60 includes a metallic printing unit 63, a color printing unit 64, a pinning control unit 65, and a curing control unit 66. The metallic printing unit 63 ejects metallic ink onto the workpiece 5 supported on the support base 25 to form a metallic layer L12, as shown in step S103 of Figure 6. As shown in step S106 of Figure 6, the color printing unit 64 ejects color ink onto the metallic layer L12 formed on the substrate 5 to form a color printing layer L13. As shown in step S107 of Figure 6, the pinning control unit 65 irradiates the color printing layer L13 with light from the light irradiation device 35 at a pinning peak illuminance L21 (see Figure 9) to perform pinning on the color printing layer L13. As shown in step S108 of Figure 6, after pinning to the color printing layer L13 by the pinning control unit 65, the curing control unit 66 irradiates the color printing layer L13 with light from the light irradiation device 35 at a curing peak illuminance L22 (see Figure 9) which is higher than the pinning peak illuminance L21 to perform curing on the color printing layer L13.

[0077] Thus, as shown in Figure 5, even when a color printing layer L13 is formed on top of a metallic layer L12, pinning is performed on the color printing layer L13 to partially cure it. Then, curing is performed on the pinned color printing layer L13 to fully cure it. In this way, by performing pinning on the color printing layer L13, the brightness of the color ink can be ensured.

[0078] In this embodiment, the pinning control unit 65 ensures that the pinning peak illuminance L21 is 0.025 W / cm² when performing pinning on the color printing layer L13. 2 To increase the brightness, pinning is performed on the color printing layer L13. For example, if the pinning peak illuminance L21 of the color printing layer L13 is too high, the color ink will harden before it can spread, making it difficult to obtain sufficient brightness for the color ink. Also, if the pinning peak illuminance L21 of the color printing layer L13 is too low, wrinkles or bleeding may easily occur on the substrate 5. In this embodiment, by setting the pinning peak illuminance L21 of the color printing layer L13 within the above range, it is possible to ensure the brightness of the color ink while making it difficult for wrinkles and bleeding to occur on the substrate 5.

[0079] In this embodiment, the curing control unit 66 performs curing on the color printing layer L13 when the curing peak illuminance L22 is 1.0 W / cm². 2 ~2.5W / cm 2 To achieve this, curing is performed on the color printing layer L13. This ensures that the color printing layer L13 is completely cured.

[0080] In this embodiment, the pinning control unit 65 determines that the integrated light amount on the color printing layer L13 when performing pinning on the color printing layer L13 is 40 mJ / cm². 2 ~200 mJ / cm 2 To achieve this, pinning is performed on the color printing layer L13. The curing control unit 66 performs curing on the color printing layer L13 when the integrated light amount on the color printing layer L13 is 1000 mJ / cm². 2 ~2500 mJ / cm 2 Curing is performed on the color printing layer L13 to achieve the above result. By adjusting the illuminance of the light irradiation device 35 during pinning and curing so that the cumulative light amount is as described above, it is possible to ensure the brightness of the color ink while suppressing the occurrence of wrinkles and bleeding of the printed material 5.

[0081] In this embodiment, the color printing unit 64 ejects color ink such that the surface tension of the color ink ejected onto the color printing layer L13 is 22 mN / m to 31 mN / m, thereby forming the color printing layer L13. By setting the surface tension of the color ink within this range, the color ink is less likely to spread, thus ensuring the brightness of the color ink.

[0082] In this embodiment, the color ink includes process color ink. The process color ink comprises cyan ink, magenta ink, yellow ink, and black ink. The color printing section 64 has a cyan ink content of 2.6 g / m². 2 ~12.8g / m 2 The magenta ink has an ink content of 2.6 g / m². 2 ~12.8g / m 2 The ink volume of the yellow ink is 2.6 g / m². 2 ~5.1g / m 2 , and the ink volume of the black ink is 2.6 g / m². 2 ~5.1g / m 2 The color inks are ejected in such a manner to form the color printing layer L13. For example, if the amount of color ink is too large, the metallic layer L12 will be more obscured by the color printing layer L13, making it difficult to express the texture of the metallic layer L12 and increasing the likelihood of wrinkles forming on the printed material 5. On the other hand, if the amount of color ink is too small, it will be difficult to obtain the desired color. Therefore, by setting the amounts of cyan ink, magenta ink, yellow ink, and black ink within the above range, it is possible to ensure the color development of the color inks, maintain the texture of the metallic layer L12, and reduce the likelihood of wrinkles forming on the printed material 5.

[0083] In this embodiment, the pinning control unit 65 irradiates the metallic layer L12 with light from the light irradiation device 35, as shown in step S104 of Figure 6, to perform pinning on the metallic layer L12. After the pinning of the metallic layer L12 by the pinning control unit 65, the curing control unit 66 irradiates the metallic layer L12 with light from the light irradiation device 35, as shown in step S105 of Figure 6, to perform curing on the metallic layer L12. After the curing of the metallic layer L12 by the curing control unit 66, the color printing unit 64 ejects color ink onto the metallic layer L12, as shown in step S106 of Figure 6, to form the color printing layer L13. In this way, by sequentially performing pinning and curing on the metallic layer L12, it is possible to form the color printing layer L13 on the metallic layer L12 while ensuring the brightness of the metallic ink and completely curing the metallic layer.

[0084] In this embodiment, the pinning peak illuminance L21 when performing pinning on the metallic layer L12 is different from the pinning peak illuminance L21 when performing pinning on the color printing layer L13. This allows the pinning peak illuminance L21 to be adjusted according to the characteristics of the metallic ink and the color ink. Therefore, optimal pinning can be performed on the metallic layer L12 and the color printing layer L13.

[0085] In this embodiment, as shown in Figure 4, the ink head 32 is equipped with a primer nozzle row 34Ba having primer nozzles 33Ba for dispensing primer ink. The control device 60 includes a primer printing unit 62 (see Figure 3) that dispenses primer ink onto the workpiece 5 supported on the support base 25 to form a primer layer L11, as shown in step S101 of Figure 6. The curing control unit 66 performs curing on the primer layer L11 by irradiating it with light from the light irradiation device 35, as shown in step S102 of Figure 6. The metallic printing unit 63 dispenses metallic ink onto the primer layer L11 after curing by the curing control unit 66, as shown in step S103 of Figure 6, to form a metallic layer L12. As a result, the metallic layer L12 is formed on top of the fully cured primer layer L11, ensuring the texture of the metallic layer L12. [Explanation of Symbols]

[0086] 5 Printing material 10 Printers 25 Support stand 32 Inkheads 33A Color Nozzle 33Ba Primer Nozzle 33Bb Metallic Nozzle 34A Color Nozzle Row 34Ba primer nozzle row 34Bb Metallic Nozzle Row 35 Light irradiation device 60 Control device 62 Primer printing section 63 Metallic Printing Section 64 Color Printing Section 65 Pinning Control Unit 66 Curing Control Unit L11 Primer layer L12 Metallic Layer L13 Color Printing Layer L21 Pinning Peak Illuminance L22 Curing Peak Illuminance

Claims

1. A support stand for supporting the printed material, An ink head that ejects ink toward the print to be supported on the support base, A light irradiation device that irradiates light onto the printed material supported on the support base, Control device and Equipped with, The aforementioned ink head is A row of color nozzles having color nozzles that eject color ink, A metallic nozzle array having metallic nozzles that eject metallic ink, Equipped with, The control device is A metallic printing unit that dispenses the metallic ink onto the substrate supported by the support base to form a metallic layer, A color printing unit that ejects the color ink onto the metallic layer formed on the substrate to form a color printing layer, A pinning control unit that irradiates the color printing layer with light from the light irradiation device at the pinning peak illuminance to perform pinning on the color printing layer, After pinning the color printing layer by the pinning control unit, the curing control unit irradiates the color printing layer with light from the light irradiation device at a curing peak illuminance higher than the pinning peak illuminance to perform curing on the color printing layer. A printer equipped with [a specific feature / ability].

2. The pinning control unit determines that the pinning peak illuminance when performing pinning on the color printing layer is 0.025 W / cm². ２ The printer according to claim 1, wherein pinning is performed on the color printing layer to make it larger.

3. The curing control unit performs curing on the color printing layer when the curing peak illuminance is 1.0 W / cm². ２ ~2.5 W / cm ２ The printer according to claim 2, wherein curing is performed on the color printing layer to achieve the above.

4. The pinning control unit performs pinning on the color printing layer, and the integrated light amount on the color printing layer is 40 mJ / cm². ２ ~200 mJ / cm ２ To that end, perform pinning on the color printing layer, The curing control unit, when curing the color printing layer, determines that the integrated light amount on the color printing layer is 1000 mJ / cm². ２ ~2500mJ / cm ２ The printer according to claim 1, wherein curing is performed on the color printing layer to achieve the above.

5. The printer according to claim 1, wherein the color printing unit forms the color printing layer by ejecting the color ink such that the surface tension of the color ink ejected onto the color printing layer is 22 mN / m to 31 mN / m.

6. The aforementioned color inks include process color inks. The aforementioned process color ink is Cyan ink and, Magenta ink and, Yellow ink and, Black ink and, It has, The color printing unit discharges the color ink so that the ink amount of cyan ink is 2.6 g / m ２ to 12.8 g / m ２ , the ink amount of magenta ink is 2.6 g / m ２ to 12.8 g / m ２ , the ink amount of yellow ink is 2.6 g / m ２ to 5.1 g / m ２ , and the ink amount of black ink is 2.6 g / m ２ to 5.1 g / m ２ to form the color printing layer, and the printer according to claim 1.

7. The pinning control unit irradiates the metallic layer with light from the light irradiation device to perform pinning on the metallic layer. The curing control unit, after the pinning of the metallic layer by the pinning control unit, irradiates the metallic layer with light from the light irradiation device to perform curing on the metallic layer. The printer according to claim 1, wherein the color printing unit, after curing the metallic layer by the curing control unit, ejects the color ink onto the metallic layer to form the color printing layer.

8. The printer according to claim 7, wherein the pinning peak illuminance when performing pinning on the metallic layer is different from the pinning peak illuminance when performing pinning on the color printing layer.

9. The ink head comprises a row of primer nozzles having primer nozzles for ejecting primer ink, The control device includes a primer printing unit that dispenses the primer ink onto the workpiece supported on the support base to form a primer layer. The curing control unit irradiates the primer layer with light from the light irradiation device to perform curing on the primer layer. The printer according to claim 1, wherein the metallic printing unit, after curing the primer layer by the curing control unit, ejects the metallic ink onto the primer layer to form the metallic layer.

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