JP7464378B2 - Ink application control device and ink application method - Google Patents

Description

The present invention relates to an ink application control device and an ink application method.

A technique is known for forming a resist film for etching by inkjet printing (Patent Document 1). When forming a resist film by spin coating, a photolithography process is required. Inkjet printing does not require the photolithography process, so the number of processes can be reduced.

JP 2010-56266 A

When the liquid repellency of the surface of the substrate to which ink is to be applied increases, the phenomenon of ink droplets that land on the surface of the substrate being attracted to each other is likely to occur. When droplets are attracted to each other, even if the ink lands, the ink may move across the surface from the point of impact, resulting in areas where the ink is not applied. The object of the present invention is to provide an ink application control device and an ink application method that can suppress the occurrence of areas where ink is not applied.

According to one aspect of the present invention,
An ink application control device including a control unit that controls application of ink to a predetermined area of a substrate,
The control unit is
applying ink to an edge region along the edge of an application region to be ink-applied and to an inner region spaced apart from the edge region such that a film of ink covering the edge region does not come into contact with a film of ink covering the inner region;
An inking control device is provided that applies ink to the edge region and the inner region and then applies ink to a gap region between the edge region and the inner region.

According to another aspect of the invention,
An ink application control device including a control unit that controls application of ink to a predetermined area of a substrate,
a border region that extends along the edge of a coating region to be coated with ink and is defined over the entire periphery of the coating region , and a plurality of pixels that are to be landing positions of ink are aligned in the length direction of the edge, and two pixels are aligned in the width direction;
An ink application control device is provided in which, when the control unit lands ink on the pixels of the edge region, it lands ink on at least every other pixel in the length direction of the edge region, and then it lands ink on the pixels between the pixels where ink has landed, and for two pixels lined up in the width direction of the edge region, it lands ink on the inner pixel before the outer pixel.

According to yet another aspect of the present invention,
applying ink to an edge region along an edge of a coating region to be coated on a substrate surface and to an inner region spaced apart from the edge region such that a film of ink covering the edge region does not come into contact with a film of ink covering the inner region;
An ink application method is provided in which, after applying ink to the edge region and the inner region, ink is applied to a gap region between the edge region and the inner region.

According to yet another aspect of the present invention,
a substrate having a coating area on a surface of which ink is to be applied, the coating area extending along the edge of the coating area and defined around the entire periphery of the coating area , a plurality of pixels serving as target landing positions of ink are aligned in the length direction of the edge and two pixels are aligned in the width direction,
In the length direction of the edge region, ink is deposited on at least every other pixel;
Then, ink is deposited on the pixels between the pixels where ink has already been deposited,
With respect to two pixels aligned in the width direction of the edge region, an ink application method is provided in which ink is deposited on the inner pixel before the outer pixel.

By applying ink to the edge and inner regions and then applying ink to the gap regions, it is possible to prevent the occurrence of areas where ink is not applied.

FIG. 1A is a schematic front view of an ink application device equipped with an ink application control device according to an embodiment, and FIG. 1B is a diagram showing the positional relationship in a plan view of a movable table and an ink ejection unit. FIG. 2A is a plan view of a portion of a substrate at an intermediate stage of ink application, and FIG. 2B is a plan view of a portion of the substrate after ink application has been completed. 3A and 3B are plan views of a coating area coated with ink by the ink coating method according to the comparative example, showing an intermediate stage and the completed coating, respectively. FIG. 4A is a diagram showing a schematic diagram of image data that defines the shape and position of a coating region, and FIG. 4B is a diagram showing the positional relationship between pixels and ink droplets that have landed on a substrate. 5A and 5B are diagrams showing the corresponding relationships between the edge region, the inner region, and the gap region and the pixels, and showing the pixels on which ink has landed. FIG. 6A is a diagram showing a cell consisting of four pixels arranged in two rows and two columns, and FIGS. 6B to 6E are diagrams showing the pixels onto which ink is landed during the first to fourth scans, respectively. 7A to 7D are diagrams showing pixels on which ink is landed during the first to fourth scans when applying ink to the gap region, respectively. FIG. 8 is a diagram showing the planar shape of ink that has landed and hardened on pixels in the edge regions on the left and top sides of FIGS. 6B to 6E. FIG. 9A is a plan view showing an example of an arrangement of a plurality of coating regions, and FIG. 9B is an enlarged plan view showing gaps between the coating regions when the edges of the coating regions are wavy. 10A and 10B are diagrams showing pixels on which ink is landed in the first and second scans, respectively. 11A and 11B are diagrams showing pixels on which ink is landed during the third and fourth scans, respectively. FIG. 12A is a diagram showing cells containing pixels on which ink will land in the first to fourth scans, along with serial numbers; FIG. 12B is a diagram showing cells containing pixels on which ink will land in the fifth to eighth scans, along with serial numbers; and FIG. 12C and FIG. 12D are diagrams showing pixels on which ink will land in the first and second scans, respectively. 13A and 13B are diagrams showing pixels on which ink is landed during the third and fourth scans, respectively. 14A and 14B are diagrams showing pixels on which ink is landed during the fifth and sixth scans, respectively. 15A and 15B are diagrams showing pixels on which ink is landed during the seventh and eighth scans, respectively.

With reference to Figures 1A to 2B, an ink application control device according to one embodiment of the present invention will be described.

Figure 1A is a schematic front view of an ink application device equipped with an ink application control device according to this embodiment. A movable table 12 is supported on a base 10 by a movement mechanism 11. An xyz Cartesian coordinate system is defined in which the x-axis and y-axis are oriented horizontally and the z-axis is oriented vertically upward. The movement mechanism 11 is controlled by the ink application control device 50 to move the movable table 12 in two directions, the x-direction and the y-direction. As the movement mechanism 11, for example, an XY stage including an X-direction movement mechanism 11X and a Y-direction movement mechanism 11Y can be used. The X-direction movement mechanism 11X moves the Y-direction movement mechanism 11Y in the x-direction relative to the base 10, and the Y-direction movement mechanism 11Y moves the movable table 12 in the y-direction relative to the base 10.

The substrate 20 to be coated with ink is held on the upper surface (holding surface) of the movable table 12. The substrate 20 is fixed to the movable table 12 by, for example, a vacuum chuck. Above the movable table 12, an ink ejection unit 30 is supported by, for example, a gate-shaped support member 13 so that it can be raised and lowered relative to the base 10. The ink ejection unit 30 has multiple nozzle holes facing the substrate 20. Photocurable (e.g., ultraviolet curable) ink is ejected in the form of droplets from each nozzle hole toward the surface of the substrate 20. The ejection of the ink is controlled by an ink application control device 50.

In FIG. 1A, an example is shown in which the ink ejection unit 30 is stationary relative to the base 10 and the substrate 20 is moved, but the opposite may be true, in which the substrate 20 is stationary relative to the base 10 and the ink ejection unit 30 is moved. In this way, one of the substrate 20 and the ink ejection unit 30 may be moved relative to the other.

The ink application control device 50 includes a memory unit 51 and a control unit 52. The memory unit 51 stores image data that defines the shape of the application area to which ink is to be applied and the position within the surface of the substrate 20. The control unit 52 controls the movement mechanism 11 and the ink ejection unit 30 based on this image data to cause ink droplets to land at predetermined positions on the surface of the substrate 20. The control unit 52 applies ink within the application area by causing ink droplets to land at multiple positions within the application area. As a result, a film made of ink is formed on the surface of the substrate 20.

Figure 1B is a diagram showing the positional relationship between the movable table 12 and the ink ejection unit 30 in a plan view. The substrate 20 is held on the holding surface of the movable table 12. The ink ejection unit 30 is supported above the substrate 20. The ink ejection unit 30 includes an inkjet head 31 and a curing light source 33. A plurality of nozzle holes 32 are provided on the surface of the inkjet head 31 facing the substrate 20. The plurality of nozzle holes 32 are arranged at equal intervals in the x direction. This interval is a dimension corresponding to a resolution of, for example, 600 dpi. Note that the plurality of nozzle holes 32 do not need to be arranged on a single straight line parallel to the x direction, and may be arranged at positions regularly shifted in the y direction from a reference line parallel to the x direction.

The curing light sources 33 are arranged on both sides of the inkjet head 31 in the y direction, and function as curing devices that cure the ink attached to the substrate 20. The movement mechanism 11 is controlled by the ink application control device 50 to move the movable table 12 in the x and y directions. Furthermore, the ink application control device 50 controls the ejection of ink from each nozzle hole 32 of the inkjet head 31.

By discharging ink from the inkjet head 31 in droplet form while moving the substrate 20 in the y direction, the ink can be applied to the substrate 20 at a resolution of, for example, 600 dpi in the x direction. The ink attached to the substrate 20 is cured by light emitted from a curing light source 33 located downstream in the direction of movement of the substrate 20. The process of discharging ink from the inkjet head 31 in droplet form while moving the substrate 20 in the y direction is referred to as "scanning". By shifting the substrate 20 in the x direction by 1/2 the interval equivalent to 600 dpi and performing two scans, the ink can be landed on the substrate 20 at a resolution of 1200 dpi in the x direction.

By performing two scans, ink can be applied to an area with a width equivalent to the distance between the nozzle holes 32 at both ends in the x direction. If the dimensions of the substrate 20 are greater than the distance between the nozzle holes 32 at both ends, ink can be applied to the entire substrate 20 by shifting the substrate 20 in the x direction and performing multiple scans.

Next, the ink application method according to this embodiment will be described with reference to FIGS. 2A and 2B.
Fig. 2A is a plan view of a portion of a substrate 20 at an intermediate stage of ink application. A plurality of application areas 21 to be applied with ink are defined on the surface of the substrate 20. Fig. 2A shows one application area 21.

Within the application area 21, an edge area 22 along the edge of the application area 21 and an inner area 23 spaced apart from the edge area 22 are defined. The area inside the edge area 22 and outside the inner area 23, i.e., the area between the edge area 22 and the inner area 23, is referred to as the gap area 24. The edge area 22 is defined around the entire circumference of the application area 21.

First, the control unit 52 controls the moving mechanism 11 and the inkjet head 31 to apply ink to the edge region 22 and the inner region 23. In FIG. 2A, the area where ink is applied is hatched from top to bottom. At this time, the ink applied to the edge region 22 and the ink applied to the inner region 23 are prevented from contacting each other. In other words, the width of the gap region 24 is ensured so that the ink applied to the edge region 22 and the ink applied to the inner region 23 do not come into contact with each other. At this point, the ink applied to the edge region 22 and the inner region 23 is irradiated with light from the curing light source 33 (FIG. 1B) during scanning and cured.

Figure 2B is a plan view of a portion of the substrate 20 after ink application has been completed. After applying ink to the edge region 22 and inner region 23, the control unit 52 applies ink to the gap region 24. In Figure 2B, the region where ink has been applied in this process is hatched downward to the right. Through the process up to this point, ink has been applied and cured over the entire application region 21, forming an ink film.

Next, we will explain the excellent effects of the embodiment shown in Figures 1A to 2B while comparing it with the comparative example shown in Figures 3A and 3B.

Figures 3A and 3B are plan views of a coating area 21 coated with ink by an ink coating method according to a comparative example, at an intermediate stage and at the end of coating, respectively. In the comparative example, an edge area 22 and an inner area 23 are defined within the coating area 21, and no gap area 24 (Figures 2A and 2B) is provided between them. In other words, the edge area 22 and the inner area 23 are in contact. In the ink coating method according to the comparative example, as shown in Figure 3A, ink is first applied to the edge area 22. In Figure 3A, the area coated with ink is hatched with an upward sloping right edge. Then, as shown in Figure 3B, ink is applied to the inner area 23. In Figure 3B, the area coated with ink in this process is hatched with an downward sloping right edge.

Focusing on the area very close to the edge on the inner periphery of the edge region 22, when ink is applied to the inner region 23, a state may occur in which a film of hardened ink has already formed on the edge region 22 side, while no film has formed on the innermost part. If the surface of the substrate 20 is highly liquid repellent, the ink droplets that land on the surface of the substrate 20 are attracted to the hardened ink film of the edge region 22 during the period until they are hardened. This results in an uncoated region 25, where no ink has been applied, occurring slightly inside the edge region 22. Note that ink is applied to the edge region 22 before the ink is applied to the inner region 23 in order to increase the straightness of the outer periphery of the film formed by the ink.

2A and 2B, when ink is applied to the gap region 24, an ink film is formed on the outer periphery of the gap region 24 to cover the edge region 22, and an ink film is formed on the inner depth side to cover the inner region 23. This suppresses the phenomenon in which ink droplets that land in the gap region 24 are attracted only in one direction, either the outer periphery or the inner depth. This suppresses the occurrence of uncoated regions 25 (FIG. 3B). Uncoated regions 25 are likely to occur when the substrate 20 has liquid repellency such that the contact angle of the ink on the surface of the substrate 20 is 90° or more. Therefore, it is particularly preferable to apply this embodiment when applying ink using a substrate and ink that have liquid repellency such that the contact angle is 90° or more.

In addition, in this embodiment, ink is applied to both the edge region 22 and the inner region 23 in one scan, but since the inks applied to both regions do not come into contact with each other, the phenomenon of ink droplets landing on the edge region 22 being attracted to the inner depths of the applied region 21 does not occur. This makes it possible to suppress a decrease in the linearity of the outer periphery of the ink film applied to the applied region 21.

Next, a modification of the embodiment shown in FIGS. 1A to 2B will be described.
In the above embodiment, the control unit 52 moves the movable table 12 relative to the stationary inkjet head 31 and controls the ejection of ink from the inkjet head 31, thereby causing ink to land at a target position on the surface of the substrate 20. As another configuration, the inkjet head 31 may be moved instead of moving the movable table 12. Also, the movable table 12 may be moved in one direction, and the inkjet head 31 may be moved in a direction perpendicular to the moving direction of the movable table 12. Furthermore, the control unit 52 may control an ink application mechanism capable of applying ink by depositing droplets of ink at target positions on the surface of the substrate 20.

Next, an ink application control device and an ink application method according to another embodiment will be described with reference to Figures 4A to 9B. Below, a description of the configuration common to the embodiment shown in Figures 1A to 2B will be omitted.

Figure 4A is a schematic diagram of image data 40 that defines the shape and position of the coating area 21 (Figures 2A and 2B). The shape and position of the coating area 21 are defined by a plurality of pixels 41 arranged in a matrix. On the surface of the substrate 20 (Figures 2A and 2B), positions corresponding to the pixels 41 are the target landing positions of the ink droplets. For example, the column direction of the plurality of pixels 41 corresponds to the scanning direction (y direction in Figure 1B), and the row direction corresponds to the direction in which the nozzle holes 32 are arranged at equal intervals (x direction in Figure 1B).

Figure 4B is a diagram showing the positional relationship between the pixel 41 and the ink droplet 60 that has landed on the substrate 20 in a plan view. The ink droplet 60 that has landed on the substrate 20 is approximately circular in a plan view. If there is no deviation in the ink landing position, the center position of the ink droplet 60 coincides with the center position of the landing target pixel 41. In a plan view, one pixel 41 is contained in the ink droplet 60 that has landed on that pixel 41. The ink droplet 60 does not spread to the center position of the adjacent pixel 41. In other words, the diameter of the ink droplet 60 is less than twice the pixel pitch. Therefore, the ink that has landed on two adjacent pixels 41 contact each other to form a continuous film. The ink that has landed on two pixels 41 separated by one pixel 41 does not contact each other. As an example, the pixel pitch is 21.125 μm (corresponding to a pitch of 1200 dpi), and the diameter of the ink droplets 60 is 30 μm or more and 40 μm or less.

5A and 5B are diagrams showing the correspondence between the edge region 22, the inner region 23, and the gap region 24 and the multiple pixels 41, and the pixels 41 on which ink has landed. The multiple pixels 41 corresponding to the edge region 22 are lined up in the length direction of the edge region 22 (the circumferential direction of the application region 21). Two pixels 41 are lined up in the width direction of the edge region 22. That is, the edge region 22 is composed of two pixel rows in which multiple pixels 41 are lined up in the circumferential direction. As for the gap region 24, three pixels 41 are lined up in the width direction. That is, the interval between the edge region 22 and the inner region 23 corresponds to three pitches of the pixels 41. It can also be said that the width of the gap region 24 is wider than the diameter of the ink droplet that has landed on the substrate 20 and narrower than three times the diameter of the ink droplet.

In the ink application method according to this embodiment, as in the method according to the embodiment shown in Figures 2A and 2B, as shown in Figure 5A, ink is first deposited on pixels 41 in the edge region 22 and inner region 23. Ink is not deposited on pixels 41 in the gap region 24. In Figure 5A, the pixels 41 on which ink droplets have landed are hatched. Next, as shown in Figure 5B, ink is deposited on pixels 41 in the gap region 24. In Figure 5B, the pixels 41 on which ink droplets have landed in this process are hatched with relatively darker colors.

Next, an example of the order in which ink is deposited on multiple pixels 41 in the edge region 22 and the inner region 23 will be described with reference to Figures 6A to 6E.

Figure 6A is a diagram showing a cell 42 consisting of four pixels 41 arranged in two rows and two columns. The four pixels 41 included in one cell 42 are assigned serial numbers from 1 to 4. For example, the serial number 4 is assigned to the pixel 41 in the first row and first column (upper left), the serial number 3 is assigned to the pixel 41 in the first row and second column (upper right), the serial number 2 is assigned to the pixel 41 in the second row and first column (lower left), and the serial number 1 is assigned to the pixel 41 in the second row and second column (lower right). A cell 42 is formed by grouping four of the multiple pixels 41 in the coating area 21. At this time, the multiple cells 42 are grouped so that they are arranged in a matrix with no gaps. In Figures 6B to 6E, the boundaries of the cells 42 are indicated by solid lines, and the boundaries of the pixels 41 within the cells 42 are indicated by dashed lines.

In this embodiment, ink is deposited on pixels 41 with the same serial number in multiple cells 42 in one scan. A total of four scans are performed to deposit ink on all pixels 41 in the edge region 22 and inner region 23.

Figures 6B to 6E are diagrams showing pixels 41 on which ink will land during the first to fourth scans, respectively. Figures 6B to 6E show some pixels 41 located near the upper left corner of the coating area 21. In Figures 6B to 6E, pixels 41 on which ink will land during the current scan are marked with relatively dark hatching, and pixels 41 on which ink droplets have landed by the previous scan are marked with relatively light hatching.

In the first scan, as shown in FIG. 6B, ink is deposited on pixel 41 with serial number 1 in cell 42. In the second scan, as shown in FIG. 6C, ink is deposited on pixel 41 with serial number 2 in cell 42. In the third scan, as shown in FIG. 6D, ink is deposited on pixel 41 with serial number 3 in cell 42. In the fourth scan, as shown in FIG. 6E, ink is deposited on pixel 41 with serial number 4 in cell 42. By performing four scans, ink can be deposited on all pixels 41 in the edge region 22 and the inner region 23.

As shown in Figures 6B to 6E, in the length direction of the edge region 22, ink is deposited on every other pixel 41 in one scan. For two pixels 41 aligned in the width direction of the edge region 22, ink is deposited on the pixel 41 on the inner periphery before the pixel 41 on the outer periphery.

In the inner region 23, as shown in FIG. 6B, in the first scan, ink is deposited on pixels 41 in every other row and every other column. In the second scan, as shown in FIG. 6C, ink is deposited on pixels 41 in rows where ink has landed but where ink has not yet landed. In the third scan, as shown in FIG. 6D, ink is deposited on pixels 41 in rows where ink has not yet landed but where ink has not yet landed. In the fourth scan, as shown in FIG. 6E, ink is deposited on pixels 41 in rows where ink has not yet landed.

Next, an example of the order in which ink is landed on the pixels 41 in the gap region 24 will be described with reference to Figures 7A to 7D. A total of four scans are performed to land ink on all pixels 41 in the gap region 24.

Figures 7A to 7D are diagrams showing pixels 41 on which ink will land during the first to fourth scans when applying ink to the gap region 24, respectively. Figures 7A to 7D show some pixels 41 located near the upper left corner of the application region 21. In Figures 7A to 7D, pixels 41 on which ink will land during the current scan are marked with relatively dark hatching, and pixels 41 on which ink droplets have landed by the previous scan are marked with relatively light hatching.

In the first scan, as shown in FIG. 7A, ink is deposited on every other pixel 41 in the length direction at multiple pixels 41 located in the width direction center of the gap region 24. In the second scan, as shown in FIG. 7B, ink is deposited on the pixel 41 between the pixel 41 where ink has landed and the edge region 22, and on the pixel 41 between the pixel 41 where ink has landed and the inner region 23. In the third scan, as shown in FIG. 7C, ink is deposited on the pixel 41 located in the width direction center where ink has not landed. In the fourth scan, as shown in FIG. 7D, ink is deposited on the pixel 41 in the gap region 24 where ink has not landed.

As shown in Figures 7A to 7D, when focusing on three pixels 41 aligned in the width direction within the gap region 24, ink is first deposited on the central pixel 41, and then ink is deposited on the pixels 41 at both ends. The ink that lands on the central pixel 41 in the width direction does not come into contact with either the ink applied to the edge region 22 or the inner region 23. The ink that lands on the pixels 41 at both ends in the width direction comes into contact with both the ink that has already landed in the gap region 24 and the ink applied to the edge region 22, or both the ink that has already landed in the gap region 24 and the ink applied to the inner region 23.

Next, we will explain the excellent effects of this embodiment. First, we will explain the excellent effects when focusing on the application of ink to the gap area 24.

In this embodiment, when ink lands in the gap region 24, focusing on three pixels 41 aligned in the width direction, ink lands on the central pixel 41 before the pixels 41 on either end, as shown in Figures 7A and 7C. The ink that lands on the central pixel 41 does not come into contact with either the ink film in the edge region 22 or the inner region 23. Therefore, the ink that lands on the central pixel 41 is not drawn to either the edge region 22 or the inner region 23.

As shown in FIG. 7B, the ink that lands on the two end pixels 41 of the three pixels 41 aligned in the width direction comes into contact with both the ink that has already landed on the central pixel 41 and the ink that has been applied to either the edge region 22 or the inner region 23. Since the ink that has landed on the central pixel 41 has already hardened, even if it is connected to the ink film in the edge region 22 or the inner region 23 via the ink that has landed on the two end pixels 41, it is not attracted to the edge region 22 or the inner region 23. As shown in FIG. 7D, the ink that lands in the fourth scan comes into contact with the ink that has already landed on the four adjacent pixels 41 on all four sides, and is therefore not attracted in any one direction. In this way, the ink that has landed in the gap region 24 is not attracted in any one direction, and the occurrence of uncoated regions can be suppressed.

Next, referring to Figure 8, we will explain the excellent effects when focusing on the application of ink to the edge region 22.

Figure 8 is a diagram showing the planar shape of ink that has landed and hardened on pixels 41 in the edge regions 22 on the top and left sides of the application region 21 shown in Figures 6B to 6E. The regions covered with ink that has landed in the first to fourth scans are numbered 1 to 4, respectively.

Before the first scan, no ink has landed on any of the pixels 41, so the ink that has landed in the first scan (FIG. 6B) has a nearly circular planar shape. The ink that has landed in the second scan (FIG. 6C) comes into contact with the ink that has landed and hardened in the first scan before it is cured, and is attracted to it. For this reason, on the left side, the ink that has landed in the area indicated by the dashed line is attracted to the ink located inside the application area 21, causing the edge on the outer periphery to move slightly inward. On the top side, it is attracted to the ink on both sides that has landed in the first scan. As a result, the edges of the pixels 41 where the ink lands in the second scan are recessed, and the edges of the pixels 41 where the ink lands in the first scan are protruding, resulting in a wavy edge.

The ink that lands on the left side during the third scan (Figure 6D) is attracted to the ink on both sides that has landed and hardened during the first and second scans. The ink that lands on the top side during the third scan (Figure 6D) is attracted to the ink that has landed and hardened during the first and second scans, located inside the application area 21. In this way, the ink film in the edge area 22 formed by the third scan has a shape in which the edge on the outer periphery side is significantly wavy and the edge on the inner periphery side is slightly wavy. The convex portion of the edge on the outer periphery side of the edge area 22 has a larger area in a plan view than the concave portion.

In the fourth scan (Figure 6E), ink lands in the recesses of the wavy edge on the outer periphery of the ink film in the edge region 22 that has been formed by the third scan. This ink fills in the recesses, reducing the amplitude of the wavy edge on the outer periphery of the edge region 22. In other words, the straightness of the outer periphery edge is increased. In this way, in this embodiment, the straightness of the outer periphery edge of the ink film applied to the edge region 22 can be increased.

Next, referring to Figures 9A and 9B, we will explain the excellent effects of applying ink to multiple square or rectangular application areas 21 arranged in a matrix using the ink application method of this embodiment.

Figure 9A is a plan view showing an example of an arrangement of multiple coating areas 21. Multiple square or rectangular coating areas 21 are arranged in a matrix. Such an arrangement of coating areas 21 is used, for example, as an etching resist film when forming transparent electrodes of a touch panel. Transparent electrodes are formed by etching a transparent conductive film using a resist film made of ink applied to the coating areas 21 as an etching mask. To increase the resolution of the touch panel, it is desirable to narrow the spacing between the transparent electrodes. To narrow the spacing between the transparent electrodes, the spacing between the coating areas 21 must be narrowed.

Figure 9B is an example of a plan view showing an enlarged view of the gap between the coating areas 21 when the edges of the coating areas 21 are wavy. When the spacing between the coating areas 21 becomes narrower, there is an increased risk that the convex portions of the edges of adjacent coating areas 21 will come into contact with each other. If the ink applied to the two coating areas 21 becomes connected, the two transparent electrodes will be electrically short-circuited.

By using the ink application method according to this embodiment, the linearity of the edges of the application areas 21 can be increased, so that even if the distance between the application areas 21 is narrowed, the ink applied to the two application areas 21 is less likely to come into contact with each other. This has the excellent effect of making it less likely for short circuits to occur in the transparent electrodes.

Figures 6B to 6E explain the ink landing order for multiple pixels 41 in the edge region 22 located on the top and left sides of the application region 21. Next, with reference to Figures 10A to 11B, an example of the ink landing order for multiple pixels 41 in the edge region 22 located on the right side in addition to the top and left sides will be explained.

Figures 10A to 11B are diagrams showing pixels 41 on which ink will land in the first to fourth scans, respectively. The boundaries of cells 42 are shown with solid lines, and the boundaries of pixels 41 within cells 42 are shown with dashed lines. In the first to fourth scans, ink is landed on pixels 41 with serial numbers 1 to 4 in the edge region 22 and inner region 23, respectively. In Figures 10A to 11B, as in Figures 6B to 6E, pixels 41 on which ink will land in the current scan are marked with relatively dark hatching, and pixels 41 on which ink droplets have landed by the previous scan are marked with relatively light hatching.

When the number of pixels in the row direction in the coating area 21 is an even number, in the first scan, as shown in FIG. 10A, in the edge area 22 on the left side of the coating area 21, ink lands on the pixels 41 on the inner periphery of the edge area 22, but in the edge area 22 on the right side, ink lands on the pixels 41 on the outer periphery. In the edge area 22 on the left side, the ink landing order is the same as in the cases shown in FIG. 6B to FIG. 6E. In the edge area 22 on the right side, in the second scan, ink lands on the pixels 41 on the inner periphery as shown in FIG. 10B. In the third scan, ink lands on the pixels 41 on the outer periphery as shown in FIG. 11A. In the fourth scan, ink lands on the pixels 41 on the inner periphery as shown in FIG. 11B.

In this way, in the edge region 22 on the right side of the coating region 21, when focusing on two pixels 41 aligned in the width direction of the edge region 22, ink lands on the pixel 41 on the outer periphery before the pixel 41 on the inner periphery. For this reason, the effect of increasing the straightness of the edge as described with reference to FIG. 8 cannot be obtained. When the number of pixels in the row direction of the coating region 21 is an even number, the straightness of the edge of one of the edge regions 22 on the left and right sides can be increased, but the effect of increasing the straightness of the other edge region 22 is not sufficient. Similarly, when the number of pixels in the column direction of the coating region 21 is an even number, the straightness of the edge of one of the edge regions 22 on the upper and lower sides can be increased, but the effect of increasing the straightness of the other edge region 22 is not sufficient.

In this way, even if a sufficient effect of increasing the straightness can be obtained only on one of the left and right sides, or only on one of the top and bottom sides, it is possible to increase the straightness of one of the opposing edges of two application areas 21 adjacent to each other in the row or column direction in FIG. 9A. This provides the effect of suppressing contact between the inks applied to the two application areas 21.

Next, referring to Figures 12A to 15B, an ink application control device and an ink application method according to still another embodiment will be described. Hereinafter, a description of the configuration common to the embodiments shown in Figures 1A to 2B, 4A to 9B, and 10A to 11B will be omitted. In the embodiment shown in Figures 10A to 11B, when the number of pixels in the row direction of the application area 21 is an even number, an excellent effect of improving the straightness of the left side of the application area 21 is obtained, but a sufficient effect of improving the straightness of the right side is not obtained. In contrast, in the embodiment shown in Figures 12A to 15B, even if the number of pixels in the row direction of the application area 21 is an even number, a sufficient effect of improving the straightness of the left and right sides of the application area 21 is obtained. In this embodiment, ink is landed on all pixels 41 in the edge area 22 by performing a total of eight scans.

Figure 12A is a diagram showing cells 42 including pixels 41 on which ink is to be landed in the first to fourth scans, together with serial numbers. Figure 12B is a diagram showing cells 42 including pixels 41 on which ink is to be landed in the fifth to eighth scans, together with serial numbers. The serial numbers assigned to the pixels 41 of the cells 42 shown in Figure 12A are the same as those of the cells 42 shown in Figure 6A. In the cell 42 shown in Figure 12B, the pixels 41 at the bottom right, bottom left, top right, and top left are assigned serial numbers 5 to 8, respectively. In the i-th scan, ink is landed on the pixel with serial number i. In this embodiment, ink is landed on the pixels 41 on the inner periphery of the edge region 22 in the first to fourth scans, and ink is landed on the pixels 41 on the outer periphery of the edge region 22 in the fifth to eighth scans.

Figure 12C is a diagram showing pixels 41 on which ink is to land in the first scan. In the edge regions 22 on the top and left sides, pixel 41 with serial number 1 is located on the inner periphery, so ink is landed on pixel 41 with serial number 1. In the edge regions 22 on the right and bottom sides, pixel 41 with serial number 1 is located on the outer periphery, so ink is not landed on these pixels 41. Furthermore, ink is also landed on pixel 41 with serial number 1 in the inner region 23.

Figure 12D is a diagram showing pixels 41 on which ink will land in the second scan. In the edge regions 22 on the upper and right sides, pixel 41 with serial number 2 is located on the inner periphery, so ink is landed on pixel 41 with serial number 2. In the edge regions 22 on the left and lower sides, pixel 41 with serial number 2 is located on the outer periphery, so ink is not landed on these pixels 41. Furthermore, ink is also landed on pixel 41 with serial number 2 in the inner region 23.

Figure 13A is a diagram showing pixels 41 on which ink will land in the third scan. In the edge regions 22 on the left and bottom sides, pixel 41 with serial number 3 is located on the inner periphery, so ink is landed on pixel 41 with serial number 3. In the edge regions 22 on the top and right sides, pixel 41 with serial number 3 is located on the outer periphery, so ink is not landed on these pixels 41. Furthermore, ink is also landed on pixel 41 with serial number 3 in the inner region 23.

Figure 13B is a diagram showing pixels 41 on which ink lands in the fourth scan. In the edge regions 22 on the right and bottom sides, pixel 41 with serial number 4 is located on the inner periphery, so ink lands on pixel 41 with serial number 4. In the edge regions 22 on the top and left sides, pixel 41 with serial number 4 is located on the outer periphery, so ink does not lands on these pixels 41. Furthermore, ink is also landed on pixel 41 with serial number 4 in the inner region 23. By the first through fourth scans, ink lands on all pixels 41 on the inner periphery of the edge region 22 and all pixels 41 in the inner region 23.

Figure 14A is a diagram showing a pixel 41 on which ink is to land in the fifth scan. In the fifth scan, ink is to land on pixel 41 at the position of serial number 5 in cell 42 shown in Figure 12B. In the edge regions 22 on the right and bottom sides, pixel 41 with serial number 5 is located on the outer periphery, so ink is to land on pixel 41 with serial number 5. In the edge regions 22 on the top and left sides, pixel 41 with serial number 5 is located on the inner periphery, so ink is not to land on these pixels 41.

Figure 14B is a diagram showing pixels 41 on which ink will land in the sixth scan. In the edge regions 22 on the left and bottom sides, pixel 41 with serial number 6 is located on the outer periphery, so ink is landed on pixel 41 with serial number 6. In the edge regions 22 on the top and right sides, pixel 41 with serial number 6 is located on the inner periphery, so ink is not landed on these pixels 41.

Figure 15A is a diagram showing pixels 41 on which ink will land in the seventh scan. In the edge regions 22 on the top and right sides, pixel 41 with serial number 7 is located on the outer periphery, so ink is landed on pixel 41 with serial number 7. In the edge regions 22 on the left and bottom sides, pixel 41 with serial number 7 is located on the inner periphery, so ink is not landed on these pixels 41.

Figure 15B is a diagram showing pixels 41 on which ink will land in the eighth scan. In the upper and left edge regions 22, pixel 41 with serial number 8 is located on the outer periphery, so ink is landed on pixel 41 with serial number 8. In the right and bottom edge regions 22, pixel 41 with serial number 8 is located on the inner periphery, so ink is not landed on these pixels 41. By the fifth to eighth scans, ink lands on all pixels 41 on the outer periphery of the edge region 22.

Next, the excellent effects of the embodiment shown in FIGS. 12A to 15B will be described.
In this embodiment, when focusing on two pixels 41 lined up in the width direction of the edge region 22, ink lands on the inner pixel 41 before the outer pixel 41 throughout the entire edge region 22. For this reason, as described with reference to Fig. 8, it is possible to improve the straightness of the edge on the outer periphery side of the edge region 22. When multiple coating regions 21 are arranged in a matrix with gaps between them, as shown in Fig. 9A, it is possible to further narrow the gap between the coating regions 21.

Next, a modified example of the above embodiment will be described. In the above embodiment, the application area 21 (Figures 2A, 2B, etc.) is square or rectangular, but the shape of the application area 21 may be other than square or rectangular. For example, if part of the edge is parallel to the row or column direction of the pixel array, it is possible to apply the ink application method of the above embodiment to this edge.

The above-described embodiments are merely examples, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. Similar effects due to similar configurations in multiple embodiments will not be mentioned one after another. Furthermore, the present invention is not limited to the above-described embodiments. For example, it will be obvious to those skilled in the art that various modifications, improvements, combinations, etc. are possible.

REFERENCE SIGNS LIST 10 Base 11 Movement mechanism 11X x-direction movement mechanism 11Y y-direction movement mechanism 12 Movable table 13 Support member 20 Substrate 21 Coating area 22 Edge area 23 Inner area 24 Gap area 25 Uncoated area 30 Ink ejection unit 31 Inkjet head 32 Nozzle hole 33 Curing light source 40 Image data 41 Pixel 42 Cell 50 Ink coating control device 51 Memory unit 52 Control unit 60 Ink droplets landed on substrate

Claims (7)

An ink application control device including a control unit that controls application of ink to a predetermined area of a substrate,
The control unit is
applying ink to an edge region along the edge of an application region to be ink-applied and to an inner region spaced apart from the edge region such that a film of ink covering the edge region does not come into contact with a film of ink covering the inner region;
an ink application control device that applies ink to the edge region and the inner region, and then applies ink to a gap region between the edge region and the inner region; The ink application control device according to claim 1, wherein the control unit, when applying ink to the gap region, applies the ink so as not to come into contact with either the edge region or the inner region, and then applies the ink so as to come into contact with both the ink applied to the gap region and the ink applied to the edge region, and to come into contact with both the ink applied to the gap region and the ink applied to the inner region. a plurality of pixels that are the target landing positions of the ink in the edge region are aligned in the length direction of the edge region, and two pixels are aligned in the width direction of the edge region;
3. The ink application control device according to claim 1, wherein, when causing ink to land on pixels in the edge region, the control unit causes ink to land on at least every other pixel in the length direction of the edge region, and then causes ink to land on pixels between the pixels where ink has already landed, and causes ink to land on pixels on the inner side prior to pixels on the outer side in the width direction of the edge region. A plurality of pixels that are target landing positions of ink in the inner region are arranged in a matrix,
4. The ink application control device according to claim 1, wherein, when depositing ink on multiple pixels in the inner region, the control unit deposits ink in every other row and every other column, then deposits ink on pixels in the row where ink has been deposited but where ink has not yet been deposited, then deposits ink in every other column on multiple pixels in the row where ink has not yet been deposited, and then deposits ink on the pixels in the row where ink has not yet been deposited, thereby depositing ink on all pixels in the inner region. An ink application control device including a control unit that controls application of ink to a predetermined area of a substrate,
a border region that extends along the edge of a coating region to be coated with ink and is defined over the entire periphery of the coating region , and a plurality of pixels that are to be landing positions of ink are aligned in the length direction of the edge, and two pixels are aligned in the width direction;
The control unit is an ink application control device that, when landing ink on pixels in the edge region, causes ink to land on at least every other pixel in the length direction of the edge region, and then causes ink to land on pixels between the pixels where ink has already landed, and for two pixels lined up in the width direction of the edge region, causes ink to land on the inner pixel before the outer pixel. applying ink to an edge region along an edge of a coating region to be coated on a substrate surface and to an inner region spaced apart from the edge region such that a film of ink covering the edge region does not come into contact with a film of ink covering the inner region;
An ink application method comprising applying ink to the edge region and the inner region, and then applying ink to a gap region between the edge region and the inner region. a substrate having a coating area on a surface of which ink is to be applied, the coating area extending along the edge of the coating area and defined around the entire periphery of the coating area , a plurality of pixels serving as target landing positions of ink are aligned in the length direction of the edge, and two pixels are aligned in the width direction;
In the length direction of the edge region, ink is deposited on at least every other pixel;
Then, ink is deposited on the pixels between the pixels where ink has already been deposited,
The ink application method includes, for two pixels aligned in the width direction of the edge region, causing ink to land on the inner pixel before the outer pixel.

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