JP2011161824A - Inkjet printer and printing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To print a color image on a recording medium and also to print a linear pattern on a surface of the color image through one process. <P>SOLUTION: A head unit 3 on which an inkjet head 6 to eject ultraviolet curing type ink to a medium is mounted, and ultraviolet irradiation devices 4 arranged in front and at the rear of the head unit 3 in a scanning direction S and radiating ultraviolet rays to the medium are mounted on a carriage 2 moving back and forth in the scanning direction S. Color ink is ejected from a first ejection area A1 of the inkjet head 6 and clear ink is ejected from a second ejection area A2 thereof. The color image is formed with the color ink ejected from the first ejection area A1, and a concentric-circle pattern is formed on the surface of the color image with the clear ink ejected from the second ejection area A2. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an inkjet printer and a printing method for discharging ultraviolet curable ink.

  Conventionally, as described in Patent Document 1, it has been considered to form a metal-like appearance by screen printing a concentric pattern on a recording medium.

JP 2005-1111685 A

  However, in the technique described in Patent Document 1, when a color image is printed on a recording medium and a concentric pattern is printed on the surface of the color image, the color image is once printed on the recording medium. After completion, there is a problem that it is necessary to print a concentric pattern on the recording medium after the recording medium is returned to its original state.

  Accordingly, an object of the present invention is to provide an ink jet printer and a printing method capable of printing a color image on a recording medium and printing a linear pattern on the surface of the color image in one step.

  An inkjet printer according to the present invention includes a carriage that is movable in a scanning direction, an ink ejection unit that is mounted on the carriage and ejects ultraviolet curable ink onto a recording medium, and is mounted on the carriage and in the scanning direction of the ink ejection unit. An ultraviolet irradiation unit disposed on at least one of the front side and the rear side to irradiate the recording medium with ultraviolet rays; and a control unit that performs carriage movement control, ink ejection control of the ink ejection unit, and ultraviolet irradiation control of the ultraviolet irradiation unit. An ink jet printer in which the recording medium moves relative to the ink discharge means in a feed direction orthogonal to the scanning direction, and the control means is a first discharge area disposed on the front side in the feed direction of the ink discharge means To discharge the first UV curable ink and feed the ink discharge means The second ultraviolet curable ink is ejected from the second ejection area disposed on the rear side of the first ejection area from the second ejection area on the surface of the image formed by the color ultraviolet curable ink ejected from the first ejection area. A linear pattern is formed by the discharged transparent ultraviolet curable ink.

  According to the ink jet printer of the present invention, the first ultraviolet curable ink is ejected from the first ejection region disposed on the front side in the feed direction, and the second ejection region is disposed on the rear side in the feed direction. In order to discharge the ultraviolet curable ink, an image of the first ultraviolet curable ink can be formed on the surface of the recording medium in one step in which the recording medium and the ink discharging means are relatively moved in the feed direction. In addition, a linear pattern of the second ultraviolet curable ink can be formed on the surface of the image.

  In this case, the first ultraviolet curable ink is preferably a colored ultraviolet curable ink, and the second ultraviolet curable ink is preferably a light transmissive ultraviolet curable ink. As described above, by ejecting the UV curable ink having translucency from the second ejection region, the visibility of the color image formed by the color UV curable ink ejected from the first ejection region is greatly hindered. The decorativeness can be given to the color image without any problem.

  The ink discharge means may discharge 5% by volume or less of colored ultraviolet curable ink with respect to the ultraviolet curable ink discharged from the second discharge region from a region in front of the second discharge region in the scanning direction. good. As a result, the color ink of 5% by volume or less is mixed with the clear ink in one scan, so that a linear pattern can be colored and higher decorativeness can be given.

  The linear pattern preferably has a line thickness of 0.09 to 0.71 mm, a line height of 10 μm or more, and a line interval of 0.5 to 0.9 mm. Thus, by setting the pattern parameters, it is possible to obtain a metal-like appearance.

  Further, the linear pattern is preferably concentric. Thus, by making the pattern concentric, it is possible to achieve an appearance in which the reflected light appears to rotate.

  A printing method according to the present invention includes a carriage that is movable in the scanning direction, an ink ejection unit that is mounted on the carriage and ejects ultraviolet curable ink onto a recording medium, and is mounted on the carriage and in the scanning direction of the ink ejection unit. An ultraviolet irradiation unit disposed on at least one of the front side and the rear side to irradiate the recording medium with ultraviolet rays; and a control unit that performs carriage movement control, ink ejection control of the ink ejection unit, and ultraviolet irradiation control of the ultraviolet irradiation unit. A printing method of an ink jet printer in which a recording medium moves relative to an ink ejection unit in a feed direction orthogonal to the scanning direction, from a first ejection region disposed on the front side in the feed direction of the ink ejection unit The first ultraviolet curable ink is ejected and the rear side in the feed direction of the ink ejection means The second ultraviolet curable ink is ejected from the second ejection area, and the transparent surface ejected from the second ejection area is formed on the surface of the image formed by the color ultraviolet curable ink ejected from the first ejection area. A linear pattern is formed by ultraviolet curable ink.

  According to the printing method of the present invention, the first ultraviolet curable ink is ejected from the first ejection region disposed on the front side in the feed direction, and the second ejection region is disposed on the rear side in the feed direction. In order to discharge the ultraviolet curable ink, an image of the first ultraviolet curable ink can be formed on the surface of the recording medium in one step in which the recording medium and the ink discharging means are relatively moved in the feed direction. In addition, a linear pattern of the second ultraviolet curable ink can be formed on the surface of the image.

  In this case, the line thickness is 0.09 to 0.71 mm, the line height is 10 μm or more, and the line interval is 0.5 to 0.9 mm by the transparent ultraviolet curable ink discharged from the second discharge region. It is preferable to form a linear pattern. Thus, by setting the pattern parameters, it is possible to obtain a metal-like appearance.

  According to the present invention, a color image can be printed on a recording medium in one step, and a linear pattern can be printed on the surface of the color image.

1 is a schematic diagram illustrating an inkjet printer according to an embodiment. It is a figure which shows the operation example for demonstrating printing operation. It is a figure which shows another linear pattern. It is a figure which shows the operation example for demonstrating another printing operation. It is a figure which shows the parameter of an Example. It is a figure which shows the observation result of an Example.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an inkjet printer and a printing method according to the invention will be described in detail with reference to the drawings. The ink jet printer according to the embodiment forms an image on a medium by discharging the ultraviolet curable ink as droplets and irradiating the ultraviolet curable ink landed on the medium with ultraviolet rays to cure. In the drawings, the same or corresponding parts are denoted by the same reference numerals.

  FIG. 1 is a schematic view showing an ink jet printer according to this embodiment. As shown in FIG. 1, an ink jet printer 1 according to this embodiment includes a carriage 2 that can reciprocate in a scanning direction S, a head unit 3 that is mounted on the carriage 2 and on which a plurality of ink jet heads 6 are mounted, and a carriage. 2, an ultraviolet irradiation device 4 a disposed in front of the scanning direction S of the head unit 3, an ultraviolet irradiation device 4 b mounted on the carriage 2 and disposed behind the scanning direction S of the head unit 3, and the inkjet printer 1. And a control unit 8 that performs printing control. The ink jet printer 1 transports the medium in the feed direction F perpendicular to the scanning direction S by the path width, and moves the carriage 2 in the scanning direction S to eject ultraviolet curable ink from the ink jet head 6. At the same time, an image is formed on the medium by performing scanning by irradiating ultraviolet rays from the ultraviolet irradiation device 4a and the ultraviolet irradiation device 4b.

  The carriage 2 is held so as to be capable of reciprocating in the scanning direction S above a platen (not shown) through which the medium is conveyed. The carriage 2 is movably held by, for example, a guide rail (not shown) extending in the scanning direction S, and reciprocates in the scanning direction S along the guide rail by driving a drive mechanism (not shown) such as a drive motor. It can be moved.

  The head unit 3 is an ink ejection device in which a plurality of inkjet heads 6 (6a to 6f) that eject ultraviolet curable ink are incorporated. Since the head unit 3 is mounted on the carriage 2, it is possible to discharge ultraviolet curable ink from each inkjet head 6 when moving in the scanning direction S accompanying the movement of the carriage 2. The inkjet head 6a to the inkjet head 6f are provided along the scanning direction S. In the scanning direction S, the inkjet head 6a, the inkjet head 6b, the inkjet head 6c, the inkjet head 6d, and the inkjet are arranged from the front to the rear. The head 6e and the inkjet head 6f are arranged in this order.

  Each inkjet head 6 is formed with a plurality of nozzles (not shown) that discharge ultraviolet curable ink as droplets. The plurality of nozzles form a nozzle row arranged to extend in the feed direction F. Then, colored ultraviolet curable ink (hereinafter also referred to as “color ink”) is ejected from the inkjet heads 6a to 6d arranged on the front side in the scanning direction S, and the inkjet head arranged on the rear side in the scanning direction S. 6c and the inkjet head 6d discharge ultraviolet curable ink having translucency (hereinafter also referred to as “clear ink”). More specifically, black (K) color ink is ejected from the nozzle row of the inkjet head 6a. Yellow (Y) color ink is ejected from the nozzle row of the inkjet head 6b. Cyan (C) color ink is ejected from the nozzle row of the inkjet head 6c. Magenta (M) color ink is ejected from the nozzle row of the inkjet head 6d. Also, clear ink (CL) is ejected from each nozzle row of the inkjet head 6e and the inkjet head 6f.

  Of the nozzle arrays formed in the inkjet head 6a to inkjet head 6d that eject the color ink, the color ink is ejected only from the nozzle array of the first ejection area A1 arranged in the rear half in the feed direction F, and the feed Color ink is not ejected from the nozzle rows arranged in the front half in the direction F. On the other hand, the clear ink is ejected only from the nozzle row of the second ejection area A2 arranged in the front half in the feed direction F among the nozzle rows formed in the inkjet head 6e and the inkjet head 6f that eject the clear ink, and feed Clear ink is not ejected from the nozzle rows arranged in the rear half in the direction F. For this reason, for the medium conveyed in the feed direction F, first, the color ink ejected from the first ejection area A1 of the inkjet head 6a to the inkjet head 6d is applied to the surface of the media. Then, the clear ink ejected from the second ejection area A2 of the inkjet head 6e and the inkjet head 6f is applied to the surface (upper layer) of the color ink.

  Although each inkjet head 6 has been described as ejecting only one type of ink, a plurality of nozzle rows may be formed in the scanning direction S, and the type of ink ejected may be changed for each nozzle row.

  Since the ultraviolet irradiation device 4a and the ultraviolet irradiation device 4b are configured identically, the ultraviolet irradiation device 4a and the ultraviolet irradiation device 4b will be collectively described as the ultraviolet irradiation device 4 below.

  The ultraviolet irradiation device 4 irradiates the ultraviolet curable ink applied to the medium with ultraviolet rays to cure the ultraviolet curable ink. The ultraviolet irradiation device 4 includes an ultraviolet light emitting diode (hereinafter referred to as “UVLED”) as a main component, and emits ultraviolet light when the UVLED is turned on, and stops emitting ultraviolet light when the UVLED is turned off. In the ultraviolet irradiation device 4, the UVLED is directed in the direction of a platen (not shown) through which the medium is conveyed. When the UVLED is turned on, the medium conveyed to the platen is irradiated with ultraviolet light, and the UVLED is turned off. This stops the irradiation of the medium with ultraviolet rays. Since the ultraviolet irradiation device 4 is mounted on the carriage 2, it can emit ultraviolet rays when moving in the scanning direction S accompanying the movement of the carriage 2.

  The control unit 8 performs printing control of the ink jet printer 1, and is configured mainly by a computer including a CPU, a ROM, and a RAM, for example. And each control of the control part 8 mentioned later is implement | achieved by reading predetermined computer software on CPU or RAM, and making it operate | move under control of CPU.

  The control unit 8 performs drive control of the carriage 2 and moves the carriage 2 in the scanning direction S. Further, the control unit 8 performs ink ejection control of the inkjet head 6 and also performs ultraviolet irradiation control of the ultraviolet irradiation device 4 while moving the carriage 2. Further, the control unit 8 performs conveyance control for conveying the medium in the feed direction F at a predetermined pitch.

  Ink ejection control is performed by ejecting color ink from the first ejection area A1 of the inkjet head 6a to inkjet head 6d to form a color image on the surface of the medium, and clearing from the second ejection area A2 of the inkjet head 6e and inkjet head 6f. Ink is ejected to form a linear pattern on the surface of the color image. This linear pattern is a concentric pattern, and its parameters are as follows. The line thickness is in the range of 0.09 to 0.71 mm, the line height is 10 μm or more, and the line pitch (interval between lines) is 0.5 to 0.9 mm. Note that the height of the line can be adjusted by the discharge amount of clear ink, the illuminance of ultraviolet rays, and the like, and is preferably in the range of 10 to 100 μm.

  In the ultraviolet irradiation control, the ultraviolet irradiation device 4 is turned on when printing is started, and the ultraviolet irradiation device 4 is turned off when all printing is completed. For this reason, the lighting state of the ultraviolet irradiation device 4 is maintained while the carriage 2 is moving. Note that the ultraviolet irradiation device 4 may be turned on only when the carriage 2 moves on the medium or the printed image, and the ultraviolet irradiation device 4 may be turned off when the carriage 2 is not on the medium or the printed image.

  In the inkjet printer 1 configured as described above, the color ink and the clear ink are ejected from the first ejection area A1 and the second ejection area A2 of the inkjet head 6 as the carriage 2 moves, and the ultraviolet irradiation device 4 Ultraviolet rays are emitted, and the media is sequentially conveyed in the feed direction F by the path width, whereby an image is formed on the media. Therefore, color ink is applied to the surface of the medium to form a color image, and clear ink is applied to the surface of the color image to form a concentric pattern of the above parameters.

  Next, the printing operation of the inkjet printer 1 will be described with reference to FIG. FIG. 2 is a diagram illustrating an operation example for explaining the printing operation. In the present embodiment, a printing operation when printing in two passes will be described. That is, the width (pass width) obtained by dividing the nozzle row of the inkjet head 6 by 2 that is the number of passes is defined as a single transport amount of the medium, and the same print area is printed twice (the number of passes). A printing operation will be described. Therefore, FIG. 2A shows an operation example of the first pass, FIG. 2B shows an operation example of the second pass, and FIG. 2C shows an operation example of the third pass. ing. In FIG. 2, the first area B1 of the medium M is a front area in the feed direction F, and the second area B2 of the medium M is a rear area in the feed direction F. The lengths in the feed direction F of the first area B1 and the second area B2 are the lengths in the feed direction F of the first ejection area A1 and the second ejection area A2 of the inkjet head 6 mounted on the head unit 3. It is the same.

  When the medium is conveyed in the feed direction F, the first area B1 first reaches the scanning line of the first ejection area A1, and then the second area B2 reaches the scanning line of the first ejection area A1. And the first area B1 reaches the scanning line of the second ejection area A2.

  Therefore, first, the medium M is transported in the feed direction F until the first area B1 reaches the scanning line of the first ejection area A1. Then, with the ultraviolet irradiation device 4 turned on, scanning is performed by moving the carriage 2 in the scanning direction S, and the color ink is ejected from the first ejection region A1. Then, as shown in FIG. 2A, the color ink ejected from the first ejection area A1 is applied to the first area B1 of the medium M and irradiated with ultraviolet rays, thereby forming a color image. The

  Next, the medium M is conveyed until the second area B2 reaches the scanning line of the first ejection area A1 and the first area B1 reaches the scanning line of the second ejection area A2. Then, with the ultraviolet irradiation device 4 turned on, scanning is performed by moving the carriage 2 in the scanning direction S, and color ink is ejected from the first ejection area A1 and clear ink is ejected from the second ejection area A2. . Then, as shown in FIG. 2B, the color ink ejected from the first ejection area A1 is applied to the second area B2 of the medium M and irradiated with ultraviolet rays, thereby forming a color image. The first area B1 of the medium M is coated with the clear ink ejected from the second ejection area A2 and irradiated with ultraviolet rays, whereby a concentric pattern is formed on the surface of the color image.

  Next, the medium M is conveyed until the second area B2 reaches the scanning line of the second ejection area A2. Then, with the ultraviolet irradiation device 4 turned on, scanning is performed by moving the carriage 2 in the scanning direction S, and the clear ink is ejected from the second ejection area A2. Then, as shown in FIG. 2C, the second area B2 of the medium M is coated with the clear ink ejected from the second ejection area A2 and irradiated with ultraviolet rays, so that the surface of the color image is applied. A concentric pattern is formed.

  As a result, a color image with color ink is formed on the lower layer of the medium M, and a concentric pattern of clear ink is formed on the surface (upper layer) of the color image.

  As described above, according to the inkjet printer 1 according to the present embodiment, the color ink is ejected from the first ejection area A1, and the clear ink is ejected from the second ejection area A2. In one step of relative movement, a color image with color ink can be formed on the surface of the medium, and a concentric pattern with clear ink can be formed on the surface of the color image.

  Since the color ink has translucency, the color image can be decorated without significantly impairing the visibility of the color image.

  In addition, the pattern formed with the clear ink is concentric, and the thickness, height, and pitch of the lines are set as the above parameters, so that a metal-like appearance in which the reflected light appears to rotate can be obtained.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, in the above-described embodiment, the clear ink is ejected from the second ejection region A2 to form a concentric pattern. However, the pattern may be any shape as long as it is a linear pattern. For example, as shown in FIG. 3A, a concentric pattern whose center is located outside the medium may be used, and as shown in FIG. 3B, a pattern in which a plurality of concentric circles are combined. Alternatively, it may be a linear pattern as shown in FIG. 3C, or may be a pattern in which straight lines having different inclinations are combined or overlapped as shown in FIG. .

  Moreover, in the said embodiment, the inkjet head 6a-inkjet head 6b was arrange | positioned in the same position in the feed direction F, and the 1st discharge area | region and the 2nd discharge area | region were formed by discharging ink only from a part of inkjet head. However, for example, the inkjet head 6a to the inkjet head 6f may be shifted in the feed direction F, and the inkjet head 6e and the inkjet head 6f may be disposed forward in the feed direction F of the inkjet head 6a to the inkjet head 6d.

  In the above-described embodiment, the UV LED is used as the ultraviolet irradiation device. However, any device such as a metal halide lamp may be used as long as the ultraviolet curable ink can be irradiated with ultraviolet rays.

  Further, in the above-described embodiment, it has been described that printing is performed in two passes, but the number of passes is not limited. Here, a case where printing is performed in 12 passes will be described with reference to FIG. FIG. 4 is a diagram illustrating an example of an operation for explaining another printing operation. FIG. 4A shows the first pass, FIG. 4B shows the sixth pass, and FIG. 4C shows the seventh pass. 4D shows the 12th pass, FIG. 4E shows the 13th pass, and FIG. 4F shows the 18th pass. As shown in FIG. 4, when printing in 12 passes, the width (pass width) obtained by dividing the nozzle row of the inkjet head 6 by 12 that is the number of passes is defined as a single transport amount of media, and the same print area is set. Print with 12 scans. Then, as shown in FIG. 4B, when the sixth pass is scanned, a color image is formed in the first region B1 of the medium M, as in FIG. As shown in FIG. 4D, when the 12th pass is scanned, a color image is formed in the second area B2 of the medium M, as in FIG. In the first region B1, a concentric pattern is formed on the surface of the color image. As shown in FIG. 4F, when the 18th pass is scanned, a concentric pattern is formed on the surface of the color image in the second area B2 of the medium M, as in FIG. Is formed.

  In the above embodiment, the ultraviolet curable ink is ejected only from the first ejection area A1 and the second ejection area A2 of the inkjet head 6. However, for example, the nozzle arrays of the inkjet head 6a to the inkjet head 6d Of these, 5% by volume or less of color ink may be ejected from the area disposed in the front half in the feed direction F with respect to the clear ink ejected from the second ejection area A2. As a result, the color ink of 5% by volume or less is mixed with the clear ink in one scan, so that a linear pattern can be colored and higher decorativeness can be given.

  Next, an embodiment of the present invention will be described.

  In this example, a plurality of samples are formed using the inkjet head 1 according to the above-described embodiment, and whether or not each sample has a metal appearance in which a concentric pattern appears to rotate when the medium is moved. Was observed.

  More specifically, by discharging color ink from the first discharge area A1 and discharging clear ink from the second discharge area A2, a color image is formed on the medium, and concentric circles are formed on the surface of the color image. A pattern was formed. Note that the clear ink was only transparent ultraviolet curable ink, and MIMAKI ENGINEERING product number: LH-100 Clear was used. The parameters of the concentric pattern are as follows. The thickness (line width) of the line was set to four types: 0.25 pt (0.09 mm), 0.5 pt (0.18 mm), 1 pt (0.35 mm), and 2 pt (0.71 mm). The number of lines was 8 types per 10 cm: 5, 10, 20, 50, 100, 150, 200, 300. The line height was 10 μm.

FIG. 5 shows the pitch of the lines formed by the above parameters (interval between the lines), and FIG. 5 shows the observation results. In FIG. 5, ◯ indicates that a metal-like appearance in which the concentric pattern appears to rotate is confirmed, and ○ ⁻ indicates that the concentric pattern appears to rotate although it is not sufficient. It shows that a metal-like appearance can be confirmed, and x indicates that a metal-like appearance in which a concentric pattern appears to rotate cannot be confirmed.

  As shown in FIG. 6, as a result of observation, the line height is 10 μm, the line thickness (line width) is 0.5 pt (0.09 mm) to 2 pt (0.71 mm), and the line pitch However, when it is 0.5 to 1.9 mm, a metal-like appearance in which a concentric pattern appears to rotate is confirmed, and among them, 0.5 pt (0.09 mm) to 1 pt (0.35 mm), When the line pitch was 0.5 to 0.9 mm, the above-mentioned appearance was further confirmed.

DESCRIPTION OF SYMBOLS 1 ... Inkjet printer, 2 ... Carriage, 3 ... Head unit, 4 ... Ultraviolet irradiation apparatus, 4a ... Ultraviolet irradiation apparatus, 4b ... Ultraviolet irradiation apparatus, 6 (6a-6f) ... Inkjet head, 8 ... Control part, F ... Feed Direction, S ... scanning direction, A1 ... first ejection area, A2 ... second ejection area, B1 ... first area, B2 ... second area, M ... media.

Claims (7)

A carriage movable in the scanning direction;
An ink ejection unit that is mounted on the carriage and ejects ultraviolet curable ink onto a recording medium;
Ultraviolet irradiation means mounted on the carriage and arranged at least one of the front and rear in the scanning direction of the ink ejection means to irradiate the recording medium with ultraviolet rays;
Control means for performing movement control of the carriage, ink discharge control of the ink discharge means, and ultraviolet irradiation control of the ultraviolet irradiation means;
With
An inkjet printer in which the recording medium moves relative to the ink ejection means in a feed direction orthogonal to the scanning direction;
The control means includes
From the first ejection region disposed on the front side in the feed direction of the ink ejection means, the first ultraviolet curable ink is ejected,
A second ultraviolet curable ink is ejected from a second ejection region disposed on the rear side in the feed direction of the ink ejection means;
A linear pattern is formed on the surface of an image formed by the color ultraviolet curable ink ejected from the first ejection area by the transparent ultraviolet curable ink ejected from the second ejection area. Inkjet printer. The first ultraviolet curable ink is a colored ultraviolet curable ink,
The inkjet printer according to claim 1, wherein the second ultraviolet curable ink is an ultraviolet curable ink having translucency.   The ink ejection means ejects 5% by volume or less of an ultraviolet curable ink with respect to the ultraviolet curable ink ejected from the second ejection area from a region in front of the second ejection area in the scanning direction. The inkjet printer according to claim 2. The linear pattern is
The thickness of the line is 0.09 to 0.71 mm,
The height of the line is 10 μm or more,
The line spacing is 0.5-0.9mm,
The inkjet printer according to claim 1, wherein the inkjet printer is a printer.   The inkjet printer according to claim 4, wherein the linear pattern is concentric. A carriage that is movable in the scanning direction; ink ejection means that is mounted on the carriage and that ejects ultraviolet curable ink onto a recording medium; and that is mounted on the carriage and forward and rearward in the scanning direction of the ink ejection means. An ultraviolet irradiating unit disposed on at least one to irradiate the recording medium with ultraviolet rays; and a control unit that performs movement control of the carriage, ink ejection control of the ink ejection unit, and ultraviolet irradiation control of the ultraviolet irradiation unit. A printing method of an ink jet printer in which the recording medium moves relative to the ink ejection means in a feed direction orthogonal to the scanning direction,
From the first ejection region disposed on the front side in the feed direction of the ink ejection means, the first ultraviolet curable ink is ejected,
A second ultraviolet curable ink is ejected from a second ejection region disposed on the rear side in the feed direction of the ink ejection means;
A linear pattern is formed on the surface of an image formed by the color ultraviolet curable ink ejected from the first ejection area by the transparent ultraviolet curable ink ejected from the second ejection area. Printing method. By the transparent ultraviolet curable ink discharged from the second discharge region,
The thickness of the line is 0.09 to 0.71 mm,
The height of the line is 10 μm or more,
The line spacing is 0.5-0.9mm,
The printing method according to claim 6, wherein a linear pattern is formed.