JP7663005B2 - Ink jetting device - Google Patents

Description

The present invention relates to an ink jet device.

When printing on the surface of a medium with irregularities, if the surface shape of the medium can be grasped in advance, the ink can be deposited in the correct position, resulting in distortion-free printing. The surface shape of the medium can be grasped using equipment such as a laser measuring device, but devices equipped with such equipment have a complex structure and increase manufacturing costs.

Therefore, a device has been proposed that ejects test ink onto a medium in advance and determines the surface shape of the medium based on the deviation in the landing position of the test ink (see Patent Document 1 below). With such a device, ink (color ink) can be landed in an appropriate position taking into account the surface shape of a medium that has the same surface shape as the medium onto which the test ink was ejected.

JP 2010-89286 A

Since the test ink sprayed onto the medium may affect the color produced by the color ink, the medium with the test ink adhering to it is discarded. However, discarding the medium increases the manufacturing costs of the remaining medium, which is a major problem, especially for media that are produced in small quantities and in a wide variety of varieties.

In view of these circumstances, the present invention aims to provide an ink ejection device that can grasp the surface shape of a medium by ejecting test ink onto the medium, and that eliminates the need to discard the medium to which the test ink has been applied.

An ink jetting device according to one aspect of the present invention includes an ejection head that ejects ink onto a medium, an imaging device including an imaging element that images the ink attached to the medium, and a control device, and the control device executes a test ink ejection process that ejects test ink from the ejection head onto the medium, an attachment pattern acquisition process that acquires an attachment pattern of the test ink attached to the medium based on imaging data including the test ink captured by the imaging device, a surface shape estimation process that estimates the surface shape of the medium based on the acquired attachment pattern, a color ink ejection data correction process that corrects color ink ejection data previously acquired according to the estimated surface shape of the medium, and a color ink ejection process that ejects color ink from the ejection head onto the medium based on the corrected color ink ejection data, and the test ink is transparent ink, ink of the same color as the medium, or ink of the same color as the base.

According to this configuration, the surface shape of the medium can be grasped by ejecting the test ink onto the medium. Furthermore, in this configuration, the test ink is a transparent ink, an ink of the same color as the medium, or an ink of the same color as the base. In this case, when color ink is ejected after the test ink is ejected, there is almost no difference in color development due to the color ink between the areas where the test ink is attached and the areas where it is not attached. Therefore, by using the above-mentioned test ink, the medium with the test ink attached can be used as is, and there is no need to discard it.

The above configuration makes it possible to provide an ink ejection device that can grasp the surface shape of a medium by ejecting test ink onto the medium, and that does not require the medium to which the test ink has been applied to be discarded.

FIG. 1 is a schematic diagram showing the overall configuration of an ink ejection device. FIG. 2 is a block diagram showing the configuration of a control system of the ink ejection device. FIG. 3 is a flow diagram of the ink ejection program. FIG. 4 is a diagram comparing the deposition pattern with the reference pattern.

(Overall composition)
An ink jetting device 100 according to an embodiment of the present invention will be described below. First, the overall configuration of the ink jetting device 100 will be described. The ink jetting device 100 according to this embodiment is a UV printer that irradiates ultraviolet light to ink attached to a medium 101 to cure it. However, the ink jetting device 100 is not limited to being a UV printer.

Figure 1 is a schematic diagram showing the overall configuration of an ink ejection device 100. The medium 101, which is the object to be printed in this embodiment, is an object having a three-dimensional shape with unevenness on its surface, and has a certain degree of surface roughness. In Figure 1, the semicircle on the surface of the medium 101 indicates test ink, which will be described later. The ink ejection device 100 according to this embodiment comprises an ejection head 10, an irradiation device 20, and an imaging device 30. Below, these components will be described in order.

<Injection head>
The ejection head 10 is a device that ejects ink onto the medium 101. The ejection head 10 is mounted on a carriage 40, and ejects ink while moving together with the carriage 40. The carriage 40 is moved by a carriage drive device 41 (see FIG. 2) in the left-right direction of the paper surface of FIG. 1 (scanning direction) and in a direction perpendicular to the paper surface (sub-scanning direction). However, the carriage 40 does not move in a direction perpendicular to the paper surface, and instead, a table on which the medium 101 is placed may move in a direction perpendicular to the paper surface.

The ejection head 10 ejects ink in a direction perpendicular to the surface of the medium 101 (downward in the plane of the paper in FIG. 1). Furthermore, the carriage 40 moves in a direction along the surface of the medium 101 (to the right in the plane of the paper in FIG. 1). Therefore, when viewed from the medium 101, the ink is ejected from a direction inclined to the direction perpendicular to the surface of the medium 101. As a result, if the surface of the medium 101 is uneven, and ink is ejected in the same way as if the surface were flat (in other words, if the surface was smooth), there is a risk that images or the like will appear distorted on the medium 101.

Base ink, color ink, and coating ink are ejected from the ejection head 10 of this embodiment. All of these inks are photocurable inks that are cured by light (ultraviolet light in this embodiment).

The base ink is an ink that is sprayed onto the medium 101 before the color ink is sprayed, forming a base on the surface of the medium 101. The base ink includes a primer ink and a white ink. The primer ink is transparent and can improve the adhesion between the color ink and the medium 101. The white ink is white and can improve the color development of the color ink.

Color ink is ink used to express pictures and the like on the medium 101. For example, color ink includes black ink, cyan ink, magenta ink, and yellow ink. Various colors are expressed by combining these inks. However, the inks included in the color ink are not limited to these.

The coating ink is an ink that is sprayed after the color inks to form a coating layer. The coating ink is transparent. By adjusting the surface roughness of the coating layer, a matte or glossy finish can be achieved.

<Irradiation device>
The irradiation device 20 is a device that irradiates light onto the surface of the medium 101. The irradiation device 20 is mounted on the carriage 40. The light irradiated from the irradiation device 20 includes visible light for imaging and ultraviolet light for curing ink. Note that the irradiation device 20 may be divided into a part that irradiates visible light and a part that irradiates ultraviolet light.

When the ink ejected onto the medium 101 is in droplet form, the ink forms a hemisphere on the medium 101 immediately after ejection, and gradually spreads over the medium 101 as time passes. Therefore, by adjusting the time from when the ink is ejected until it hardens (or is temporarily hardened) (hereinafter referred to as the "hardening time"), it is possible to set the shape of the hardened ink (the height of the ink). Adjusting the hardening time will be described later.

The illumination device 20 also illuminates the surface of the medium 101 from an oblique direction. Specifically, when the point on the medium 101 imaged by the imaging device 30 is taken as a reference, the illumination angle α of the light illuminated by the illumination device 20 with respect to the surface of the medium 101 (actually with respect to the direction of movement of the imaging device 30) is 0 to 15 degrees. This type of illumination method is called dark field illumination, and by shining light on the surface of the medium 101 from a direction close to horizontal, the reflected light from the surface is unlikely to reach in a direction perpendicular to the surface, and the light that hits the ink attached to the surface of the medium 101 scatters (diffuses) the light in all directions regardless of the original direction of the light, creating a clear contrast.

<Imaging device>
The imaging device 30 is a device that captures an image of ink attached to the medium 101. The imaging device 30 is mounted on a carriage 40. The imaging device 30 of this embodiment captures an image from a direction perpendicular to the surface of the medium 101 (actually, perpendicular to the moving direction of the imaging device 30). As described above, in this embodiment, the irradiation device 20 irradiates light onto the surface of the medium 101 so that the irradiation angle α is 0 to 15 degrees. In this way, since the dark field illumination method is used in this embodiment, even if the ink is a color that is difficult to see, such as transparent or white, it is possible to recognize the ink from the imaging data of the imaging device 30.

The imaging device 30 of this embodiment also uses a CCD (charge-coupled device) sensor to capture images. A CCD sensor is a sensor formed by combining a CCD, a lens, and a mirror. A CCD sensor has a deeper depth of field than a CIS sensor that is often used in general scanners. Therefore, the imaging device 30 of this embodiment can clearly capture images of ink that has hardened while retaining a three-dimensional shape, for example, ink that has hardened while remaining almost hemispherical and maintaining a certain height or more without spreading after being ejected.

(Control system configuration)
Next, the configuration of the control system of the ink ejecting device 100 will be described. Fig. 2 is a block diagram of the control system of the ink ejecting device 100. As shown in Fig. 2, the ink ejecting device 100 according to this embodiment includes a control device 50. The control device 50 includes a processor, a volatile memory, a non-volatile memory, an I/O interface, and the like. The non-volatile memory of the control device 50 stores various programs including an ink ejecting program described below, and various data, and the processor performs arithmetic processing using the volatile memory based on the various programs.

The control device 50 is electrically connected to the imaging device 30. This allows the control device 50 to obtain imaging data of the surface of the medium 101 containing the adhered ink from the imaging device 30.

Furthermore, the control device 50 is electrically connected to the ejection head 10, the irradiation device 20, and the carriage drive device 41 that drives the carriage 40. The control device 50 can control the type of ink ejected from the ejection head 10, the ejection timing, the ejection speed, the amount of ink ejected per unit time, and the size of the ink ejected (one drop) by sending a control signal to the ejection head 10 (more precisely, the actuator of the ejection head 10). The control device 50 can also control the intensity of the light irradiated from the irradiation device 20 and the irradiation timing (on/off) by sending a control signal to the irradiation device 20. Furthermore, the control device 50 can control the moving speed and moving direction of the carriage 40 by sending a control signal to the carriage drive device 41. Note that the ink deposition position on the medium 101 can be adjusted not only by controlling the ejection timing and ejection speed of the ink, but also by controlling the speed of the carriage 40.

(Ink jetting program)
Next, an ink ejection program executed by the control device 50 will be described. The ink ejection program ejects a test ink to grasp the surface shape of the medium 101, and then ejects the base ink, color ink, and coating ink in that order. Fig. 3 is a flow diagram of the ink ejection program.

<Test ink ejection process>
3, when the ink ejection program is started, the control device 50 first executes a test ink ejection process (step S1). The test ink ejection process is a process in which test ink is ejected from the ejection head 10 onto the medium 101. Here, a base ink, particularly a transparent primer ink, is used as the test ink.

In the test ink ejection process, test ink is ejected based on predetermined test ink ejection data. The test ink ejection data is data that, for example, when test ink is ejected based on the data onto a medium with a flat surface, an evenly spaced dot pattern appears on the surface of the medium. For example, if the carriage 40 is moved at a constant speed and test ink is ejected from the ejection head 10 at a constant cycle, an evenly spaced dot pattern will appear on the medium with a flat surface. Even if test ink is ejected based on such test ink ejection data, if the surface of the medium is uneven, the test ink will not necessarily appear at equal intervals on the surface of the medium.

The test ink ejection process is not limited to ejecting the test ink so as to produce a dot pattern, and may be ejected so as to produce, for example, a grid-like line pattern. When ejecting the test ink so as to produce a dot pattern, for example, one large droplet (approximately 10 picoliters) of test ink can represent one dot, and the distance between adjacent dots can be approximately 1 mm.

<Light irradiation treatment>
Next, the control device 50 executes a light irradiation process (step S2). The light irradiation process is a process in which light is irradiated from the irradiation device 20. As described above, the base ink, which is the test ink, is a photocurable ink that is cured by light. The shape of the cured test ink can be set by adjusting the curing time (the time from when the test ink is ejected until when it is cured).

The above-mentioned curing time can be adjusted by changing the time between the ejection of the test ink and the irradiation of light. For example, by moving the carriage 40 while ejecting test ink from the ejection head 10 with the irradiation device 20 turned off, and then moving the carriage 40 along the same route after a predetermined time with the irradiation device 20 turned on, the time between the ejection of the test ink and the irradiation of light can be adjusted. The curing time can also be adjusted by changing the intensity of the light emitted from the irradiation device 20.

In this embodiment, the curing time is adjusted according to the surface roughness of the medium 101. Specifically, when the surface roughness of the medium 101 is higher than the reference roughness (i.e., when the surface of the medium 101 is relatively rough), the curing time is adjusted to be longer than a predetermined reference curing time. If the curing time is long, the test ink cures in a spread state, so that the area where the test ink is applied becomes flat and smooth, and the boundary between the area where the test ink is applied and the other areas (areas with rough surfaces) becomes more noticeable. As a result, the test ink becomes easier to recognize.

On the other hand, when the surface roughness of the medium 101 is lower than the reference roughness (i.e., when the surface of the medium 101 is relatively smooth), the curing time is adjusted to be shorter than the above-mentioned reference curing time. If the curing time is short, the test ink will cure in a raised state, making the boundary between the area where the test ink is applied and the other areas (areas with smooth surfaces) more noticeable. As a result, the test ink becomes easier to recognize.

The surface roughness of the medium 101 may be input by an operator via an input device not shown. Alternatively, a measuring device for measuring the surface roughness may be provided in the ink ejection device 100, and the control device 50 may obtain the surface roughness of the medium 101 based on a measurement signal transmitted from the measuring device. The light irradiation process (step S2) may be performed in parallel with the test ink ejection process (step S1).

<Deposition pattern acquisition process>
Next, the control device 50 executes an adhesion pattern acquisition process (step S3). The adhesion pattern acquisition process is a process for acquiring a pattern of the test ink adhered to the medium 101 (hereinafter referred to as an "adhesion pattern") based on imaging data including the test ink captured by the imaging device 30.

As described above, in this embodiment, the imaging device 30 captures images using a CCD sensor, and the illumination device 20 performs a dark field illumination method in which the illumination device captures images while irradiating the surface of the medium 101 with light from a direction that forms an angle of 0 to 15 degrees. Therefore, even test inks of colors that are difficult to recognize can be reliably recognized, and the adhesion pattern can be obtained with high accuracy.

<Surface Shape Estimation Processing>
Next, the control device 50 executes a surface shape estimation process (step S4). The surface shape estimation process is a process for estimating the surface shape of the medium 101 based on the adhesion pattern acquired in step S3. Specifically, by ejecting test ink based on the test ink ejection data, a test ink pattern (hereinafter referred to as a "reference pattern") that appears on the surface of the medium 101, which has a flat surface, is compared with the adhesion pattern, and the surface shape of the medium 101 is estimated from the deviation between the two.

Figure 4 is a diagram comparing the deposition pattern with the reference pattern. Figure 4 (a) shows the deposition pattern in a cross-sectional view, (b) shows the deposition pattern in a plan view, and (c) shows the reference pattern in a plan view. The deposition pattern in (b) corresponds to the deposition pattern in (a). The semicircles in Figure 4 (a) indicate dots of test ink, and the dashed lines indicate the ejection direction of the test ink. The circles in Figure 4 (b) and (c) indicate dots of test ink. Note that the right side of the paper in Figure 4 is the movement direction of the carriage 40 when ejecting the test ink.

As shown in FIG. 4, in parts of the medium 101 where the surface rises toward the direction of movement of the carriage 40, the spacing between the test ink dots in the deposition pattern is narrower than that of the reference pattern. Therefore, in parts of the deposition pattern where the spacing between the test ink dots is narrower than that of the reference pattern, it can be assumed that the surface is inclined so that it rises toward the direction of movement of the carriage 40. Conversely, in parts of the deposition pattern where the spacing between the test ink dots is wider than that of the reference pattern, it can be assumed that the surface is inclined so that it falls toward the direction of movement of the carriage 40.

<Base ink ejection data correction process>
Next, the control device 50 executes a process of correcting the ejection data for the base ink (step S5). The ejection data for the base ink is data that the control device 50 has previously acquired, and the base ink is ejected based on this data.

For example, when base ink is ejected based on the base ink ejection data before correction (i.e., when the control device 50 acquires the base ink ejection data), if the surface of the medium 101 is flat, a base with a constant thickness is formed. On the other hand, if the surface of the medium 101 is uneven, there is a risk that a base with an inconsistent thickness will be formed. The base ink ejection data correction process is a process that corrects such base ink ejection data.

In the base ink ejection data correction process of this embodiment, a two-stage correction is performed. First, as the first stage of correction, the base ink ejection data is corrected based on the surface shape of the medium 101 estimated in step S4. Specifically, the control device 50 corrects the base ink ejection data according to the surface shape of the medium 101 so that the thickness of the base is constant across the entire surface of the medium 101. In this case, for example, the correction is made so that the amount of base ink ejected is reduced in parts of the medium 101 that are inclined to be higher toward the traveling direction of the carriage 40. Also, for example, the correction is made so that the amount of base ink ejected is increased in parts of the medium 101 that are inclined to be lower toward the traveling direction of the carriage 40.

Then, as the second stage of correction, the base ink ejection data is corrected based on the adhesion pattern of the test ink obtained in step S3. Specifically, the base ink ejection data is corrected so that the base ink does not adhere to positions on the medium 101 where the test ink is adhered. More specifically, the control device 50 generates mask data based on the adhesion pattern obtained in step S3, and corrects the base ink ejection data by multiplying the base ink ejection data by the mask data.

In addition, not only may the base ink not be applied to the positions on the medium 101 where the test ink is applied, but the amount of base ink ejected may also be reduced. Also, the amount of base ink ejected may be reduced around the positions on the medium 101 where the test ink is applied. In this case, the above mask data is generated in accordance with these processes.

<Base ink jetting treatment>
Next, the control device 50 executes a base ink ejection process (step S6). The base ink ejection process is a process in which the ejection head 10 ejects base ink onto the medium 101 based on the base ink ejection data corrected in step S5. After the base ink is ejected, the base ink attached to the medium 101 is irradiated with light to harden the base ink. As a result, a base with a uniform thickness is formed on the surface of the medium 101.

<Color ink ejection data correction process>
Next, the control device 50 executes a color ink ejection data correction process (step S7). The color ink ejection data is data that the control device 50 has previously acquired, and the color inks are ejected based on this data.

For example, when color ink is ejected based on color ink ejection data before correction (i.e., when the control device 50 acquires the color ink ejection data), if the surface of the medium 101 is flat, an undistorted image will appear on the surface of the medium 101. On the other hand, if the surface of the medium 101 is uneven, a distorted image may appear on the surface of the medium 101. The color ink ejection data correction process is a process that corrects such color ink ejection data.

In the color ink ejection data correction process of this embodiment, the color ink ejection data is corrected based on the surface shape of the medium 101 estimated in step S4. Specifically, the control device 50 corrects the color ink ejection data so that images and the like appearing on the surface of the medium 101 are not distorted. In this case, for example, the color ink ejection data is corrected so that the ejection intervals of the color ink are increased in a portion of the medium 101 that is inclined so as to rise toward the traveling direction of the carriage 40. Also, for example, the color ink ejection data is corrected so that the ejection intervals of the color ink are narrowed in a portion of the medium 101 that is inclined so as to fall toward the traveling direction of the carriage 40.

<Color ink ejection process>
Next, the control device 50 executes a color ink ejection process (step S8). The color ink ejection process is a process in which color ink is ejected from the ejection head 10 onto the medium 101 based on the color ink ejection data corrected in step S7. This allows an image without distortion to appear on the surface of the medium 101. After the color ink is ejected, light is irradiated onto the color ink attached to the medium 101 to harden the color ink.

As mentioned above, in this embodiment, a transparent base ink is used as the test ink, so there is almost no difference in color development between the areas where the test ink is attached and the areas where it is not attached. Therefore, the medium 101 with the test ink attached can be used as is, and there is no need to discard it.

<Coating ink jet data correction process>
Next, the control device 50 executes a coating ink ejection data correction process (step S9). The coating ink ejection data is data previously acquired by the control device 50, and the coating ink is ejected based on this data.

For example, when coating ink is ejected based on the coating ink ejection data before correction (i.e., when the control device 50 acquires the coating ink ejection data), a coating layer of constant thickness is formed if the surface of the medium 101 is flat. On the other hand, if the surface of the medium 101 is uneven, a coating layer of non-constant thickness may be formed. The coating ink ejection data correction process is a process for correcting such coating ink ejection data.

In the coating ink ejection data correction process of this embodiment, the coating ink ejection data is corrected based on the surface shape of the medium 101 estimated in step S4. Specifically, the coating ink ejection data is corrected according to the surface shape of the medium 101 so that the thickness of the coating layer is constant across the entire surface of the medium 101. In this case, for example, the coating ink ejection data is corrected so that the amount of coating ink ejected is reduced in parts of the medium 101 that are inclined so that they are higher in the direction of travel of the carriage 40. Also, for example, the coating ink ejection data is corrected so that the amount of coating ink ejected is increased in parts of the medium 101 that are inclined so that they are lower in the direction of travel of the carriage 40.

<Coating ink jetting process>
Next, the control device 50 executes a coating ink ejection process (step S10). The coating ink ejection process is a process in which coating ink is ejected from the ejection head 10 onto the medium 101 based on the coating ink ejection data corrected in step S9. After the coating ink is ejected, the coating ink attached to the medium 101 is irradiated with light to harden the coating ink. This forms a coating layer with a uniform thickness on the surface of the color ink on the medium 101. This ends the ink ejection program.

(Modification)
The ink jetting device 100 according to the present embodiment has been described above, but the ink jetting device 100 is not limited to the above-described configuration. For example, in the present embodiment, a transparent primer ink is used as the test ink, but a transparent coating ink may be used. Also, a transparent ink other than the primer ink and the coating ink may be used. However, when a primer ink or a coating ink is used, there is no need to prepare a separate test ink, and therefore the ink jetting device 100 can be prevented from becoming complicated.

As mentioned above, the base ink includes white ink. When using white ink as the base ink, white ink may be used as the test ink. In this case, there is almost no difference in color development due to color ink between the areas where the test ink is attached and the areas where it is not attached. Furthermore, ink of the same color as the medium 101 may be used as the test ink. In this case, the same effect can be obtained.

In addition, when coating ink is used as the test ink, the second stage correction in the above-mentioned base ink ejection data correction process (step S5), i.e., the correction based on the adhesion pattern of the test ink, can be omitted. Instead of this, two stages of correction may be performed in the coating ink ejection data correction process (step S9). Specifically, in the coating ink ejection data correction process, based on the adhesion pattern of the test ink obtained in step S3, a correction may be made so that the coating ink becomes thinner at the positions where the test ink is adhered to the medium 101. More specifically, the control device 50 may generate mask data based on the adhesion pattern obtained in step S3, and correct the coating ink ejection data by multiplying the mask data by the coating ink ejection data. By performing this process, the surface of the coating layer can be formed smoothly.

The test ink may also contain a component that fluoresces under ultraviolet light. In this case, the irradiation device 20 irradiates the test ink with ultraviolet light, causing the test ink to emit light, making it easier to recognize the test ink in the imaging data from the imaging device 30.

In addition, in this embodiment, the curing time is adjusted according to the surface roughness of the medium 101, but the size of the droplets of the ejected test ink may also be adjusted according to the surface roughness of the medium 101. For example, when the surface roughness of the medium 101 is higher than the reference roughness, the droplet size may be larger than when the surface roughness is lower than the reference roughness. Larger droplets of test ink tend to spread more easily, and smaller droplets tend not to spread as easily. Therefore, by performing the above process, the boundary between the area where the test ink is applied and the other areas tends to stand out. As a result, the test ink becomes easier to recognize.

10 Ejection head 20 Irradiation device 30 Imaging device 40 Carriage 41 Carriage driving device 50 Control device 100 Ink ejection device 101 Medium

Claims (8)

an ejection head that ejects ink onto a medium;
an imaging device that images the ink adhered to the medium;
A control device,
The control device includes:
a test ink ejection process for ejecting a test ink from the ejection head onto the medium;
an adhesion pattern acquisition process for acquiring an adhesion pattern of the test ink adhered to the medium based on imaging data including the test ink captured by the imaging device;
a surface shape estimation process for estimating a surface shape of the medium based on the obtained adhesion pattern;
a color ink ejection data correction process for correcting the color ink ejection data acquired in advance in accordance with the estimated surface shape of the medium;
a color ink ejection process for ejecting color ink from the ejection head onto the medium based on the corrected color ink ejection data;
The test ink is a base ink that forms a base before the color ink is jetted,
The control device includes:
When forming the base,
A base ink ejection data correction process for correcting the base ink ejection data acquired in advance according to the estimated surface shape of the medium;
a base ink ejection process for ejecting the base ink from the ejection head onto the medium based on the corrected base ink ejection data;
The control device, in the base ink ejection data correction process, further corrects the base ink ejection data so that the base ink is not ejected from the ejection head at positions on the medium where the test ink is attached. The ink ejection device according to claim 1 , wherein the control device, in the base ink ejection data correction process, generates mask data based on the acquired adhesion pattern, and corrects the base ink ejection data by multiplying the base ink ejection data by the mask data . an ejection head that ejects ink onto a medium;
an imaging device that images the ink adhered to the medium;
A control device,
The control device includes:
a test ink ejection process for ejecting a test ink from the ejection head onto the medium;
an adhesion pattern acquisition process for acquiring an adhesion pattern of the test ink adhered to the medium based on imaging data including the test ink captured by the imaging device;
a surface shape estimation process for estimating a surface shape of the medium based on the obtained adhesion pattern;
a color ink ejection data correction process for correcting the color ink ejection data acquired in advance in accordance with the estimated surface shape of the medium;
a color ink ejection process for ejecting color ink from the ejection head onto the medium based on the corrected color ink ejection data;
The test ink is a coating ink that forms a coating layer after the color ink is sprayed,
The control device includes:
When forming the coating layer,
a coating ink ejection data correction process for correcting previously acquired coating ink ejection data in accordance with the estimated surface shape of the medium;
a coating ink ejection process for ejecting the coating ink from the ejection head onto the medium based on the corrected coating ink ejection data;
The control device, in the coating ink ejection data correction process, further corrects the coating ink ejection data so that the coating layer is thinner at positions on the medium where the test ink is applied than at positions where the test ink is not applied . The ink ejection device according to claim 3 , wherein the control device, in the coating ink ejection data correction process, generates mask data based on the acquired adhesion pattern, and corrects the coating ink ejection data by multiplying the coating ink ejection data by the mask data . an ejection head that ejects ink onto a medium;
an imaging device that images the ink adhered to the medium;
A control device,
The control device includes:
a test ink ejection process for ejecting a test ink from the ejection head onto the medium;
an adhesion pattern acquisition process for acquiring an adhesion pattern of the test ink adhered to the medium based on imaging data including the test ink captured by the imaging device;
a surface shape estimation process for estimating a surface shape of the medium based on the obtained adhesion pattern;
a color ink ejection data correction process for correcting the color ink ejection data acquired in advance in accordance with the estimated surface shape of the medium;
a color ink ejection process for ejecting color ink from the ejection head onto the medium based on the corrected color ink ejection data;
the test ink is a transparent ink, an ink of the same color as the medium, or an ink of the same color as the base;
an illumination device that illuminates a surface of the medium with light from a direction that forms an angle of 0 to 15 degrees with respect to a moving direction of the imaging device;
The imaging device captures an image of the test ink adhered to the medium and irradiated by the irradiation device in a direction perpendicular to a moving direction of the imaging device. the test ink is a photocurable ink that is cured by light irradiated from the irradiation device,
The control device includes:
When the surface roughness of the medium is higher than a reference roughness, the irradiation device irradiates the test ink with light so that the time from when the test ink is ejected until when the test ink is cured is shorter than a reference curing time;
The ink ejection device according to claim 5, further comprising a light irradiation process for irradiating light from the irradiation device so that the time from ejection of the test ink to curing is longer than the reference curing time when the surface roughness of the medium is lower than the reference roughness . The ink jet device according to claim 5 or 6 , wherein the imaging device performs imaging using a CCD sensor. Further comprising an irradiation device for irradiating ultraviolet light,
5. An ink jetting apparatus according to claim 1 , wherein the test ink contains a component that fluoresces under ultraviolet light.

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