JP2012213951A - Droplet ejection apparatus and droplet ejection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably determine a state of ink ejection of a nozzle.SOLUTION: An ejection head is made movable to a scanning direction (scanning direction: Y direction) that is a straight one direction in a horizontal plane, and ejection pitches to the ejection part for inspection is regulated to be more broader than the ejection pitch to the recording medium in a scanning direction. For instance, when the ejection pitch to the recording medium is assumed the pitch that corresponds to 360 dpi in the x direction, and the pitch that corresponds to 360 dpi in the Y direction, the ejection pitch to the ejection part for inspection is assumed the pitch that corresponds to 360 dpi in the x direction, and the pitch that corresponds to 720 dpi in the Y direction.

Description

  The present invention relates to a droplet ejecting apparatus and a droplet ejecting method.

  The droplet ejecting apparatus includes an ejecting head in which nozzles for ejecting ink are formed. By relatively moving the ejecting head and the ejected object, the ink is ejected and arranged in a wide range of the ejected object.

In such a droplet ejecting apparatus, for example, as shown in Patent Document 1 and Patent Document 2, an inspection unit for inspecting an ink ejecting state of a nozzle is installed.
The droplet ejecting device is configured to recover the ink ejecting state of the nozzle by performing cleaning or the like on the nozzle when the inspection unit detects that the ink ejecting state of the nozzle is abnormal. Yes.

JP 2006-76067 A JP 2009-255086 A

Incidentally, in the inspection unit, ink is ejected to the inspection ejection unit, and the landed ink is imaged. The ink ejection state is performed based on the captured image data.
However, recent liquid droplet ejecting apparatuses have increased in resolution, and ink is ejected at a narrow pitch. For this reason, the inks that have landed on the inspection ejection unit may be brought into contact with each other to be integrated, and in such a case, when there is an abnormality in the ink ejection state, the nozzle that causes this abnormality It becomes difficult to specify.
In particular, when an ultraviolet curable ink is used as the ink, the ink easily wets and spreads until the ink is irradiated with ultraviolet rays. It is difficult to specify the nozzle that is present.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a droplet discharge device and a droplet discharge method that can reliably determine the ink ejection state of a nozzle.

  As means for solving the above problems, the present invention adopts the following configuration.

  According to a first aspect of the present invention, there is provided an ejection head having a nozzle that ejects ink onto an ejection target, and an inspection unit that receives the ink outside the ejection target and inspects the ink ejection state of the nozzle. The droplet ejecting apparatus adopts a configuration in which control is performed to make the ejection pitch of the ink with respect to the inspection unit wider than the ejection pitch of the ink with respect to the ejection target.

According to the present invention employing such a configuration, the ink ejection pitch with respect to the inspection unit is wider than the ink ejection pitch with respect to the ejection target.
For this reason, it is possible to prevent the ink ejected to the inspection unit from coming into contact with the adjacent ink after landing, and when there is an abnormality in the ink ejection state, the nozzle causing the abnormality can be easily identified. can do.
Therefore, according to the present invention, it is possible to reliably determine the ink ejection state of the nozzle.

  According to a second aspect, in the first aspect, the ejection head is movable in a scanning direction that is a linear direction on a horizontal plane, and the ejection pitch of the ink in the scanning direction with respect to the inspection unit is A configuration is adopted in which control is performed to make the ejection pitch wider than the ejection pitch of the ink to the ejected object.

  According to the present invention employing such a configuration, even when the ejection pitch in the scan direction is widened in the inspection unit, a plurality of nozzle rows exist, and a plurality of nozzles are adjacent to each other in the scan direction, It is possible to reliably determine the ink ejection state.

  According to a third invention, in the first or second invention, the jet head is movable in a scan direction which is a linear direction on a horizontal plane, and the jet in a direction orthogonal to the scan direction with respect to the inspection unit. A configuration is adopted in which control is performed to make the pitch wider than the ejection pitch of the ink with respect to the ejected object.

  According to the present invention employing such a configuration, in the ejection head, even when the nozzles are arranged at a narrow pitch in the direction orthogonal to the scan direction, it is possible to reliably determine the ink ejection state of each nozzle. Is possible.

  According to a fourth aspect of the present invention, in any one of the first to third aspects of the present invention, a configuration is adopted in which control is performed to make the landing diameter of the ink on the inspection portion larger than the landing diameter of the ink on the ejected object.

  According to the present invention employing such a configuration, since the landing diameter of the ink in the inspection unit increases, it is possible to increase the threshold when extracting data indicating the ink landing area from the imaging data, and the inspection unit It is possible to suppress erroneous detection of foreign matters such as dust adhering to the ink as ink.

  According to a fifth aspect of the present invention, in the fourth aspect of the present invention, a configuration is adopted in which control is performed to increase the landing diameter by ejecting ink a plurality of times at the same position of the inspection section.

  According to the present invention employing such a configuration, it is possible to easily adjust the landing diameter according to the number of ink ejections.

  A sixth invention is an ultraviolet curable ink in which the ink is cured by ultraviolet irradiation in the fifth invention, and when the ink is ejected a plurality of times to the same position of the inspection unit, On the other hand, a configuration is adopted in which control of irradiating ultraviolet rays is performed.

According to the present invention employing such a configuration, when the ink is ejected a plurality of times to the same position of the inspection unit, the subsequent ink is ejected in a state where the previously ejected ink is already cured.
Since the surface of the cured ink exhibits liquid repellency, the ink ejected later is raised, and the height of the ink can be increased.
For this reason, according to the present invention, the appearance of the ink after curing can be made darker in the inspection section, and it becomes easy to extract data indicating the ink landing area from the imaging data at the time of density detection.

  A seventh invention is the ultraviolet curable ink according to the fifth invention, wherein the ink is cured by ultraviolet irradiation, and the ink is irradiated with ultraviolet rays after being ejected a plurality of times at the same position of the inspection section. A configuration is adopted in which control is performed.

According to the present invention employing such a configuration, when the ink is ejected a plurality of times to the same position of the inspection unit, the subsequent ink is ejected in a state where the previously ejected ink is not cured.
Therefore, according to the present invention, it is possible to easily increase the ink landing diameter in the inspection unit, and when detecting the presence or absence of ink based on the size of the landing diameter, data indicating the ink landing area from the imaging data Can be easily extracted.

  An eighth invention is the ultraviolet curable ink in which the ink is cured by ultraviolet irradiation in any one of the first to seventh inventions, and the moving speed of the ejection head when ejecting the ink to the inspection unit A configuration is adopted in which control is performed so as to be slower than the moving speed of the ejection head when ejecting the ink onto the ejected object.

  According to the present invention employing such a configuration, since the moving speed of the ejection head when ejecting ink to the inspection unit is slowed, the time until the ink is irradiated with ultraviolet rays becomes longer, and the ink is removed. Can spread widely. For this reason, it is possible to easily increase the ink landing diameter in the inspection unit, and when detecting the presence / absence of ink based on the size of the landing diameter, it is easy to extract data indicating the ink landing area from the imaging data It becomes.

  A ninth invention is the ultraviolet curable ink in which the ink is cured by ultraviolet irradiation in any one of the first to seventh inventions, and the moving speed of the ejection head when ejecting the ink to the inspection unit A configuration is adopted in which control is performed to make the speed higher than the moving speed of the ejection head when ejecting the ink onto the ejected object.

According to the present invention employing such a configuration, since the moving speed of the ejection head when ejecting ink to the inspection unit is increased, the time until the ink is irradiated with ultraviolet rays can be shortened. The ink can be cured quickly.
For this reason, according to the present invention, the appearance of the ink after curing can be made darker in the inspection section, and it becomes easy to extract data indicating the ink landing area from the imaging data at the time of density detection.

  In a tenth aspect of the invention, the ink is ejected from the nozzles formed in the ejection head to the ejected object, and the ink is applied to the inspection portion provided outside the ejected object. Is a droplet ejection method for inspecting the ink ejection state of the nozzles, and adopts a configuration in which the ejection pitch of the ink with respect to the inspection unit is made wider than the ejection pitch of the ink with respect to the ejection target To do.

According to the present invention employing such a configuration, the ink ejection pitch with respect to the inspection unit is wider than the ink ejection pitch with respect to the ejection target.
For this reason, it is possible to prevent the ink ejected to the inspection unit from coming into contact with the adjacent ink after landing, and when there is an abnormality in the ink ejection state, the nozzle causing the abnormality can be easily identified. can do.
Therefore, according to the present invention, it is possible to reliably determine the ink ejection state of the nozzle.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram illustrating a schematic configuration of a droplet ejecting apparatus according to an embodiment of the present invention, where (a) is a plan view of the droplet ejecting apparatus and (b) is a side view of the droplet ejecting apparatus. (A)-(c) is a figure which shows schematic structure of an ejection head. It is a top view which shows the ejection surface (lower surface) of an ejection head. It is a bottom view which shows schematic structure of a head unit. It is a schematic diagram containing the test | inspection part 6 with which the droplet ejecting apparatus in 1st Embodiment of this invention is provided. It is a schematic diagram for demonstrating the injection pitch in the droplet injection apparatus in one Embodiment of this invention. It is a schematic diagram for demonstrating the injection pitch in the droplet injection apparatus in one Embodiment of this invention. It is a schematic diagram which shows a mode that several ink is ejected with respect to the test | inspection part in the droplet ejecting apparatus in one Embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a droplet ejecting apparatus and a droplet ejecting method according to the present invention will be described with reference to the drawings. In the following drawings, the scale of each member is appropriately changed in order to make each member a recognizable size.

1A and 1B are schematic views showing a schematic configuration of a first embodiment of a droplet ejecting apparatus according to the present invention, wherein FIG. 1A is a plan view of the droplet ejecting apparatus, and FIG. FIG. 3 is a side view of the droplet ejecting apparatus. FIGS. 1A and 1B show a case where the droplet ejecting apparatus of the present invention is applied to a printing apparatus that performs printing on a continuous long recording medium 10 (an ejected object). ing. In FIGS. 1A and 1B, reference numeral 1 denotes a droplet ejecting apparatus. The droplet ejecting apparatus 1 includes an ejecting head 20 that ejects droplets of ultraviolet curable ink as ink, and an ejecting head 20. An irradiation device 80 (see FIG. 4) for irradiating the ejected ultraviolet curable ink S (see FIG. 6 and the like) with ultraviolet rays is provided.
The droplet ejecting apparatus 1 according to the present embodiment includes a head mechanism unit 2 having an ejecting head 20, a supply / discharge mechanism unit 3, an ink supply unit (not shown), a maintenance unit 5, and an inspection unit 6. , And a control unit 60.

  The ejection head 20 is an inkjet ejection head, and includes an ink containing an ultraviolet curable component, that is, an ultraviolet curable ink S as droplets, and a recording portion of a continuous long band-shaped recording medium 10. It is sprayed toward the surface. Here, as the recording medium 10, a medium capable of recording with the ultraviolet curable ink S is used in this embodiment, and specifically, polyethylene terephthalate (PET), polyethylene (PE), polycarbonate (PC), and polypropylene are used. A flexible film such as (PP) is used.

  The supply / discharge mechanism 3 supplies the recording medium 10 to a recording position by the ejection head 20 and discharges the recording medium 10 from the recording position. The ink supply unit supplies ink stored in a storage tank (not shown) to the ejection head 20. The maintenance unit 5 performs maintenance of the ejection head 20. In this embodiment, the maintenance unit 5 recovers the nozzle ejection state by cleaning the ejection head 20.

The supply / discharge mechanism unit 3 includes a supply reel 31, a take-up reel 32, a suction unit 33, an idler roller 37, an idler roller 38, and a Y-axis scanning mechanism 42.
The Y-axis scanning mechanism 42 includes two sets of Y-axis guide rails 42a and Y-axis sliders 42b. The suction unit 33 includes a suction table 33a, a table base 43, a table lifting mechanism 44, a supply roller 34, a driven roller 34a, a medium feeding roller 36, and a driven roller 36a. Each reel and each roller are rotatable around a rotation axis, and the respective rotation axes are substantially parallel to each other.
The direction in which the recording medium 10 is fed is a direction substantially orthogonal to the rotation axes of the reels and rollers that are substantially parallel to each other. A direction parallel to the axial direction of the rotation axis of each reel and each roller is expressed as an X-axis direction, and a feeding direction of the recording medium 10 is expressed as a Y-axis direction.

  One Y-axis guide rail 42a of the Y-axis scanning mechanism 42 is disposed on each side in the X-axis direction with the suction table 33a interposed therebetween, and extends in the Y-axis direction. The Y-axis slider 42b is provided on the bottom surface of the table base 43 and is disposed on the Y-axis guide rail 42a in that state. The Y-axis slider 42b is moved on the Y-axis guide rail 42a by a Y-axis drive motor (not shown). It is configured to slide in the extending direction.

  The suction table 33 a of the suction unit 33 is fixed to a table lifting mechanism 44 fixed on the table base 43. The suction table 33a is configured to hold the recording medium 10 on the upper surface thereof, and therefore, the upper surface is a surface on the side that holds the recording medium 10, that is, a holding surface. Under such a configuration, the ultraviolet curable ink S is ejected from the ejection head 20 in a state where the recording medium 10 is held on the holding surface, and droplets of the ink land on the recording medium 10. It is like that.

  The suction table 33a is provided with a suction recess (not shown) consisting of a suction hole or suction groove connected to a negative pressure source (not shown), and the suction recess opens on the holding surface. . As a result, the recording medium 10 is held and fixed on the holding surface by being sucked and sucked by the suction recess connected to the negative pressure source in a state where the predetermined portion is positioned on the holding surface. It has become.

  The table raising / lowering mechanism 44 raises and lowers the suction table 33a in the Z-axis direction. The holding position (suction surface) of the suction table 33a becomes a predetermined position in the Z-axis direction, and the table base from the suction position. It is moved up and down between the retreat positions close to 43 and is held and fixed at each position. The position of the holding surface of the suction table 33a when in the suction position substantially coincides with the positions of the upper ends of the outer periphery of the supply roller 34 and the outer periphery of the medium feed roller 36, which will be described later.

  On both sides of the suction table 33a in the Y-axis direction, a supply roller 34 and a driven roller 34a, and a medium feeding roller 36 and a driven roller 36a are disposed. The supply roller 34 and the driven roller 34a, and the medium feeding roller 36 and the driven roller 36a are fixed to the table base 43 via a support member (not shown), and in that state, the suction table 33a is sandwiched on both sides thereof. It is arranged. The supply roller 34 and the driven roller 34a are disposed on the upstream side of the suction table 33a, that is, on the supply reel 31 side, and the medium feed roller 36 and the driven roller 36a are on the downstream side of the suction table 33a, that is, the take-up reel 32. It is arranged on the side.

  The table base 43 can be moved in the Y-axis direction by the Y-axis scanning mechanism 42 and can be held at an arbitrary position in the Y-axis direction. The suction table 33a, the supply roller 34 and the driven roller 34a, the medium feeding roller 36 and the driven roller 36a arranged on the table base 43 are also movable in the Y-axis direction by the Y-axis scanning mechanism 42. And it can hold | maintain in the arbitrary positions in a Y-axis direction.

  The supply reel 31, the idler roller 37, the suction unit 33, the idler roller 38, and the take-up reel 32 included in the supply / discharge mechanism unit 3 are arranged in this order in the Y-axis direction, which is the supply direction of the recording medium 10. The supply reel 31 side is the upstream side in the supply direction of the recording medium 10, and the take-up reel 32 side is the downstream side.

  In the suction unit 33, the supply roller 34 and the driven roller 34a, the suction table 33a, the medium feeding roller 36, and the driven roller 36a are arranged in this order in the Y-axis direction. Therefore, in the supply / discharge mechanism 3, the supply reel 31, the idler roller 37, the supply roller 34 and the driven roller 34a, the suction table 33a, the medium feeding roller 36 and the driven roller 36a, the idler roller 38, and the winding roller The reels 32 are arranged in this order in the Y-axis direction.

  A belt-shaped recording medium 10 is wound around the supply reel 31, and the recording medium 10 is fed out by rotating the supply reel 31 by a supply motor (not shown). The outer periphery of the driven roller 34a is disposed in contact with the outer periphery of the supply roller 34 and is pressed against the supply roller 34 by an urging device (not shown). The supply roller 34 is rotated by a supply motor (not shown), and the driven roller 34 a that is in direct or indirect contact with the supply roller 34 is rotated by the rotation of the supply roller 34. It has become. Under such a configuration, the recording medium 10 sandwiched between the supply roller 34 and the driven roller 34 a is fed by the rotation of the supply roller 34.

  The idler roller 37 has a rotating shaft that can swing in the Z-axis direction and is biased to one of the swing directions (downward in the present embodiment). The idler roller 37 is brought into contact with the portion of the recording medium 10 between the supply reel 31, the supply roller 34, and the driven roller 34a by the urging force. Under such a configuration, the recording medium 10 is urged by the idler roller 37, so that it is between the supply reel 31 and the idler roller 37, and between the idler roller 37, the supply roller 34, and the driven roller 34a. The part of is stretched without slack.

  Therefore, the state when the recording medium 10 is supplied and sandwiched between the supply roller 34 and the driven roller 34a is easily maintained substantially flat. Note that the amount of slack in the portion between the supply reel 31, the supply roller 34, and the driven roller 34a varies depending on the difference between the supply speed of the recording medium 10 in the supply roller 34 and the feeding speed of the recording medium 10 in the supply reel 31. To do. However, by changing the position of the idler roller 37 following the fluctuation of the slack amount, the tensioned state is maintained without slack. Similarly, the fluctuation of the slack amount of the recording medium 10 between the supply reel 31, the supply roller 34, and the driven roller 34a due to the movement of the suction unit 33 is also maintained in a tensioned state without any slack. It has become.

  The outer periphery of the driven roller 36a is disposed in contact with the outer periphery of the supply roller 36, and is pressed against the medium feeding roller 36 by an urging device (not shown). The medium feed roller 36 is rotated by a medium feed motor (not shown), and a driven roller 36a that directly or indirectly contacts the medium feed roller 36 is driven by the rotation of the medium feed roller 36. To rotate. Under such a configuration, the recording medium 10 sandwiched between the medium feeding roller 36 and the driven roller 36 a is fed by the rotation of the medium feeding roller 36.

  Here, the feed amount by the medium feed roller 36 is set to be larger than the feed amount by the supply roller 34. Further, a torque control mechanism (not shown) is incorporated in the power transmission mechanism from the medium feed motor to the medium feed roller 36. Under such a configuration, the recording medium 10 that is fed faster than the supply roller 34 by the medium feed roller 36 has a torque controlled by the torque control mechanism at a portion between the supply roller 34 and the medium feed roller 36. It is designed to be tensioned according to the tension.

  The holding surface of the suction table 33a faces the stretched portion. That is, a portion of the recording medium 10 located on the holding surface of the suction table 33a is stretched with a tension according to the torque controlled by the torque control mechanism. Here, the position of the holding surface of the suction table 33 a located at the above-described suction position substantially coincides with the position of the surface formed by the outer peripheral upper end of the medium feeding roller 36 and the outer peripheral upper end of the supply roller 34. Therefore, the holding surface of the suction table 33a located at the suction position is in contact with and holds the recording medium 10 stretched between the supply roller 34 and the medium feed roller 36.

  The suction table 33a is configured to hold the recording medium 10 on its holding surface. The holding surface is a flat surface. Therefore, the surface to be held in the recording medium 10, that is, the surface opposite to the surface to be recorded is held flat by the holding surface. Although not shown, the holding surface is provided with a suction concave portion including a suction hole or a suction groove. The suction surface is used to suck the holding surface of the recording medium 10, and the suction table 33a. It is adsorbed and held on the holding surface. That is, a negative pressure source (not shown) such as a suction pump is connected to the suction concave portion via a pipe or the like, so that the suction concave portion sucks the recording medium 10 located on the opening. ing.

The take-up reel 32 is rotated by a take-up motor (not shown), so that the recording medium 10 fed from the medium feed roller 36 is taken up by the take-up reel 32. It has become.
The idler roller 38 has a rotating shaft that can swing in the Z-axis direction and is biased in one of the swing directions. The idler roller 38 is brought into contact with the portion of the recording medium 10 between the medium feeding roller 36 and the driven roller 36 a and the take-up reel 31 by the urging force. Under such a configuration, the recording medium 10 is urged by the idler roller 38, so that the medium feeding roller 36, the driven roller 36 a and the take-up reel 31, and the idler roller 38 and the take-up reel 32. The part between is stretched without slack.

  Therefore, the recording medium 10 is easily maintained in a substantially flat state when being wound on the take-up reel 32. The amount of slack in the portion between the medium feed roller 36 and the take-up reel 32 depends on the difference between the feed speed of the recording medium 10 at the medium feed roller 36 and the take-up speed of the recording medium 10 at the take-up reel 32. fluctuate. However, by changing the position of the idler roller 38 following the fluctuation of the slack amount, the tensioned state is maintained without slack. Similarly, the fluctuation of the slack amount of the recording medium 10 between the medium feeding roller 36 and the take-up reel 32 due to the movement of the suction unit 33 is also maintained in a tensioned state without slack. ing.

  Under such a state, the recording medium 10 is sent from the supply reel 31 to the take-up reel 32, and recorded (printed) on a portion held on the holding surface of the suction table (medium holding portion) 33a in the middle. Has been made.

The head mechanism unit 2 includes a head carriage 22 and an X-axis scanning mechanism 11.
The X-axis scanning mechanism 11 includes two sets of an X-axis guide rail 11a, an X-axis slider 11b, and a support base 11d, and four guide rail support columns 11c. The support base 11d is disposed on each side of the suction table 33a in the X-axis direction with the suction table 33a interposed therebetween, and is located between the pair of Y-axis guide rails 42a and 42a. It is arranged. A maintenance unit 5 is disposed between one Y-axis guide rail 42a and the support base 11d.

  On each of the two support bases 11d and 11d, two guide rail support pillars 11c are erected on each end in the Y-axis direction, one in total. One of the two X-axis guide rails 11a is bridged between the guide rail support pillars 11c erected at the end of the support base 11d on the supply reel 31 side, and above the suction table 33a. It is arranged in a state extending in the X-axis direction. The other of the pair of X-axis guide rails 11a is bridged between the guide rail support columns 11c erected at the end of the support base 11d on the take-up reel 32 side, and the suction table 33a It is arranged in a state extending upward in the X-axis direction.

  The X-axis slider 11b is disposed on the X-axis guide rail 11a, and is configured to slide on the X-axis guide rail 11a in the extending direction by an X-axis drive motor (not shown). Is. Both ends of the bridge plate 27 of the head carriage 22 are fixed to the X-axis slider 11b supported on each of the two X-axis guide rails 11a. The bridge plate 27 having both ends fixed to the X-axis slider 11b is suspended between the two X-axis guide rails 11a while being supported by the X-axis slider 11b. Based on such a configuration, the bridge plate 27 is slid in the extending direction on the X-axis guide rail 11a by the X-axis drive motor, and at an arbitrary position in the X-axis direction. It is supposed to be retained.

  The head carriage 22 includes a bridge plate 27, a sub-carriage 28, and a head unit 21. The sub-carriage 28 is provided at substantially the center of the lower surface of the bridge plate 27, and the head unit 21 is fixed to the lower surface side of the sub-carriage 28. An ejection head 20 is provided on the lower surface side of the head unit 21, and a nozzle substrate 25 on which nozzles 24 are formed is disposed on the bottom side of the ejection head 20 as shown in FIG. . Under such a configuration, the ejection head 20 is positioned on the holding surface of the suction table 33a. At this time, the nozzle substrate 25 is opposed to the holding surface.

Here, the suction unit 33 can be moved in the Y-axis direction by the Y-axis scanning mechanism 42, and thus the holding surface of the suction table 33a can be moved in the Y-axis direction. That is, it is possible to scan the portion of the recording medium 10 held by suction on the holding surface of the suction table 33a in the Y-axis direction.
On the other hand, the ejection head 20 of the head unit 21 fixed to the sub-carriage 28 is scanned in the X-axis direction when the bridge plate 27 provided with the sub-carriage 28 is moved in the X-axis direction by the X-axis scanning mechanism 11. It is supposed to be made.
In the present embodiment, the inspection unit 6 is installed on the −X direction side of the suction table 33a. In the X-axis scanning mechanism 11, the length of the X-axis guide rail 11a is set so that the ejection head 20 can reach an inspection ejection unit 61 of the inspection unit 6 described later.

  Under such a configuration, the X-axis scanning mechanism 11 causes the ejection head 20 of the head unit 21 to scan in the X-axis direction, and the Y-axis scanning mechanism 42 suctions and holds the suction head 33 on the holding surface of the suction table 33a. Can be scanned in the Y-axis direction. That is, the nozzle 24 of the ejection head 20 can be made to face almost the entire surface of the recording medium 10 held by the holding surface of the suction table 33a.

  Therefore, the recording target portion of the recording medium 10 sucked and held on the holding surface of the suction table 33a is moved to the ejection position in the Y axis direction and stopped, and synchronized with the movement of the head unit 21 in the X axis direction. By ejecting the ultraviolet curable ink S as droplets from the ejection head 20, the droplets (dots) of the ultraviolet curable ink S can be arranged at desired positions on the recording medium 10. Therefore, main scanning for moving the head unit 21 in the X-axis direction and sub-scanning (line feed) for moving the recording medium 10 sucked and held on the holding surface of the suction table 33a in the Y-axis direction are controlled as described later. By controlling by the unit 60, the ejection head 20 of the head unit 21 is opposed to an arbitrary position on the recording medium 10 held on the holding surface of the suction table 33a, and in this state, the ultraviolet curable ink S is used as a droplet. Can be injected. As a result, a desired image can be formed (recorded) on the recording medium 10. That is, in the present embodiment, the ultraviolet curable ink S is ejected onto the recording medium 10 while the ejecting head 20 is repeatedly reciprocated in the main scanning direction (X direction), and the ejecting head 20 is further moved one way (forward movement). Each time the recording medium 10 is moved backward, the recording medium 10 is turned in the sub-scanning direction, thereby forming a desired image on the recording medium 10.

  Next, the ejection head 20 will be described with reference to FIGS. 2 (a) to 2 (c) and FIG. 2A to 2C are diagrams illustrating a schematic configuration of the ejection head 20, FIG. 2A is an external perspective view illustrating a schematic configuration of the ejection head 20, and FIG. 2B is an internal structure of the ejection head 20. FIG. 4C is a main part perspective view illustrating the nozzle part of the ejection head 20. FIG. 3 is a plan view showing an ejection surface (lower surface) of the ejection head 20, and is a diagram for explaining a schematic configuration of the nozzle row. 2A and 3, the X axis, the Y axis, and the Z axis indicate the state in which the ejection head 20 is incorporated in the droplet ejection apparatus 1. Are coincident with the X axis, the Y axis, and the (Z axis).

  As shown in FIG. 2A, the ejection head 20 is formed with a nozzle substrate 25, and a large number of nozzles 24 are linearly arranged on the nozzle substrate 25 along the Y-axis direction. A plurality of nozzle rows 70 are formed in the X-axis direction. In the present embodiment, eight nozzle rows 70 are formed as shown in FIG. In the present embodiment, these nozzle rows 70 are an image forming ink having a color material, that is, a first nozzle row 71 in which nozzles for ejecting color ink are arranged, and an undercoat or overcoat ink, that is, a color. And a second nozzle row 72 in which nozzles for ejecting clear ink, white ink, or the like without material are arranged.

  Specifically, in order from the left side in FIG. 3, as the first nozzle row 71, a first nozzle row 71C that ejects C (cyan) as color ink, and a first nozzle that ejects M (magenta). The rows 71M, the first nozzle row 71Y that ejects Y (yellow), and the first nozzle row 71K that ejects black (K) are arranged one by one. Furthermore, as the second nozzle row 72, two second nozzle rows 72CR for ejecting clear ink for undercoat and two second nozzle rows 72W for ejecting white ink for overcoat are arranged. Yes. That is, in the present embodiment, the number of the second nozzle rows 72CR and 72W is larger than the number of the first nozzle rows 71C, 71M, 71Y, and 71K that eject the color ink.

  Here, in FIG. 3, odd-numbered nozzle rows from the left side, that is, the first first nozzle row 71C, the third first nozzle row 71Y, the fifth second nozzle row 72CR, and the seventh first nozzle row 71CR. In the second nozzle row 72W, the positions of the corresponding nozzles 24 in the Y-axis direction are the same between the nozzle rows, and the intervals between the nozzles 24 along the Y-axis direction are all the same. Accordingly, the nozzles 24 in each nozzle row are arranged at an equal pitch. Similarly, in FIG. 3, the even-numbered nozzle rows from the left side, that is, the second first nozzle row 71M, the fourth first nozzle row 71K, the sixth second nozzle row 72CR, and the eighth eighth nozzle row. In the second nozzle row 72W, the positions of the corresponding nozzles 24 in the Y-axis direction are the same between the nozzle rows, and the intervals between the nozzles 24 along the Y-axis direction are all formed and arranged the same. Accordingly, the nozzles 24 in each nozzle row are arranged at an equal pitch.

However, two nozzle rows adjacent in the X-axis direction, for example, between the first nozzle row 71C and the first nozzle row 71M, between the first nozzle row 71Y and the first nozzle row 71K, Between the second nozzle rows 72CR and between the two second nozzle rows 72W, the positions of the nozzles 24 are staggered with a half-pitch shift in the Y-axis direction.
Note that each of the nozzle rows 71 and 72 is formed by arranging 180 nozzles 24 in this embodiment.
Then, the ultraviolet curable ink S is ejected as droplets from the nozzle 24 and landed on the surface of the opposing recording medium 10, so that the ejection head 20 is placed at a desired position on the recording medium 10. S can be arranged.

  As shown in FIGS. 2B and 2C, the ejection head 20 is obtained by laminating a pressure chamber plate 51 on a nozzle substrate 25 and further laminating a diaphragm 52 on the pressure chamber plate 51. The pressure chamber plate 51 is formed with a liquid pool 55 that is always filled with the ultraviolet curable ink S supplied to the ejection head 20. The liquid pool 55 includes the vibration plate 52, the nozzle substrate 25, and a wall ( (Not shown). The ultraviolet curable ink S is supplied to the liquid pool 55 via the liquid supply hole 53 of the vibration plate 52. The pressure chamber plate 51 is formed with a pressure chamber 58 partitioned by a plurality of head partition walls 57.

  The pressure chambers 58 are provided corresponding to the respective nozzles 24, and the number of the pressure chambers 58 and the number of the nozzles 24 are the same. A functional liquid is supplied to the pressure chamber 58 from a liquid pool 55 through a supply port 56 positioned between the two head partition walls 57. A set of the pressure chamber 58, the nozzle 24, and the supply port 56 of the head partition wall 57 is arranged in a line along the liquid pool 55, and the nozzles 24 arranged in a line form a nozzle line 24A. Although not shown in FIG. 2B, another nozzle row 24 </ b> A is formed on the side of the nozzle row 24 </ b> A including the nozzles 24.

  As shown in FIG. 2C, piezoelectric elements 59 are arranged on the diaphragm 52 corresponding to the respective pressure chambers 58, that is, corresponding to the individual nozzles 24. The piezoelectric element 59 has a piezoelectric layer sandwiched between a lower electrode and an upper electrode. When a driving waveform (driving voltage) is applied between the electrodes, the ultraviolet curable ink S is ejected from the corresponding nozzle 24. It is supposed to let you. Here, the piezoelectric element 59 is controlled by the control unit 60 shown in FIGS. 1 (a) and 1 (b).

Next, a schematic configuration of the head unit 21 provided in the head mechanism unit 2 will be described with reference to FIG. FIG. 4 is a bottom view showing a schematic configuration of the head unit 21. Note that the X axis and Y axis shown in FIG. 4 coincide with the X axis and Y axis shown in FIG.
As shown in FIG. 4, the head unit 21 has a unit plate 23 attached to the lower surface of the sub-carriage 28, and nine ejection heads 20 mounted on the lower surface side of the unit plate 23. Irradiation devices 80 for irradiating ultraviolet rays are respectively disposed on both sides of the ejection head 20 in the X-axis direction. In FIG. 4, nine ejection heads 20 are arranged. However, the number of ejection heads 20 is not limited to this, and for example, 15 may be arranged.

  The ejection head 20 is fixed to the unit plate 23 by a holding member (not shown) with the nozzle substrate 25 facing downward. The nine ejection heads 20 are divided in the Y-axis direction to form three head groups 20A each including three ejection heads 20 each. The nozzle row 24A of each ejection head 20 is arranged along the Y-axis direction with the head unit 21 attached to the droplet ejection device 1.

  The three ejection heads 20 constituting one head set 20A are arranged so that the ejection heads 20 of the other ejection head 20 are in the Y axis direction with respect to the nozzles 24 of the ejection heads 20 adjacent to each other. The nozzles 24 at the end are arranged with a shift of one nozzle pitch. In the three jet heads 20 included in the head set 20A under such a configuration, all the nozzles 24 are arranged at an equal pitch in the Y-axis direction when the positions of all the nozzles 24 in the X-axis direction are the same. become. In other words, at the same position in the X-axis direction, the droplets ejected from the nozzles 24 constituting the respective nozzle rows 24A of the respective ejection heads 20 are arranged in a straight line at equal intervals in the Y-axis direction by design. To land.

  Further, in the three head sets 20A included in the head unit 21, all the nozzles 24 are arranged at an equal pitch in the Y-axis direction when the positions of all the nozzles 24 in the X-axis direction are the same. In other words, at the same position in the X-axis direction, the droplets ejected from the nozzles 24 constituting the respective nozzle rows 24A of the respective ejection heads 20 are arranged in a straight line at equal intervals in the Y-axis direction by design. It has come to land. Therefore, the 18 nozzle rows 24A included in the nine ejection heads 20 in the three head sets 20A included in the head unit 21 can be handled as one nozzle row.

  The irradiation device 80 includes an ultraviolet light source (not shown), and is fixed to the sub-carriage 28 or the unit plate 23 with the ultraviolet light source facing downward. As described above, the irradiation device 80 is disposed on each side of the ejection head 20 in the X-axis direction. As a result, immediately after the ultraviolet curable ink S is ejected from the ejection head 20 toward the recording medium 10. In addition, the ultraviolet curable ink S landed on the recording medium 10 can be irradiated with ultraviolet rays. That is, the ejection head 20 ejects the ultraviolet curable ink S while being scanned (main scanning) in the X-axis direction. Therefore, when the unit plate 23 is scanned in the X-axis direction, it irradiates the recording medium 10 by irradiating the recording medium 10 with ultraviolet rays from the irradiation device 80 located on the rear side with respect to the scanning direction. The ultraviolet curable ink S can be irradiated with ultraviolet rays.

  Here, as the ultraviolet light source, a metal halide lamp, a xenon lamp, a carbon arc lamp, a chemical lamp, a low-pressure mercury lamp, a high-pressure mercury lamp, or the like can be used. An LED that emits light in the ultraviolet band can also be used.

  The ultraviolet curable ink S that is cured by ultraviolet rays irradiated from such an ultraviolet light source is prepared by adding an auxiliary agent such as an antifoaming agent or a polymerization inhibitor to a mixture of a vehicle, a photopolymerization initiator and a pigment. Can be mentioned. The vehicle is prepared by adjusting the viscosity of an oligomer, monomer or the like having photopolymerization curability with a reactive diluent. Therefore, the solvent is not volatilized for the purpose of curing the ink.

  As the vehicle, monofunctional or polyfunctional polymerizable compounds can be used. More specifically, oligomers (prepolymers) such as polyester acrylate, epoxy acrylate, and urethane acrylate can be exemplified, and these materials can also be used as a reactive diluent for adjusting the viscosity as an ink.

  As the photopolymerization initiator, benzophenone series, benzoin series, acetophenone series, and thioxanthone series are widely used. More specifically, 4-benzoyl-N, N, N-trimethyl benzene methanenannium chloride, 2-hydroxy 3- (4-benzoyl-phenoxy) -N, N, N-trimethyl 1-propylene, -N, N-dimethyl N- [2- (1-oxo-2-propenyloxy) ethyl] A quaternary ammonium salt type water-soluble organic substance such as benzene methanol bromide can be used. This type of photopolymerization initiator has different ultraviolet absorption characteristics, reaction initiation efficiency, yellowing, and the like depending on its composition, so that it is properly used depending on the color of the ink.

  As the polymerization inhibitor, any compound that has radical scavenging ability and inhibits radical polymerization can be used. However, in consideration of jetting suitability in the ink jet recording apparatus, at least one compound selected from hydroquinones, catechols, hindered amines, phenols, phenothiazines, and condensed aromatic ring quinones is preferable.

  Examples of hydroquinones include hydroquinone, hydroquinone monomethyl ether, 1-o-2,3,5-trimethylhydroquinone, 2-tert-butylhydroquinone and the like. Examples of catechols include catechol, 4-methylcatechol, 4-tert-butylcatechol and the like. Examples of hindered amines include compounds having a tetramethylpiperidinyl group.

  Examples of phenols include phenol, butylhydroxytoluene, butylhydroxyanisole, pyrogallol, gallic acid, gallic acid alkyl ester, and the like. Examples of phenothiazines include phenothiazine. Examples of the condensed aromatic ring quinones include naphthoquinone and the like.

  Furthermore, the polymerization inhibitor may be carbon black or inorganic / organic fine particles having a polymerization-inhibiting functional group introduced on the surface. Examples of the polymerization-preventing functional group include a hydroxyphenyl group, a dihydroxyphenyl group, a tetramethylpiperidinyl group, and a condensed aromatic ring.

  Examples of the ultraviolet curable ink S include color inks containing color materials (color components) such as pigments and dyes, and clear inks for undercoat and overcoat. In addition, a white ink and a black ink that are used for overcoating, although containing a color material, can also be used.

Next, the inspection unit 6 will be described with reference to FIG. FIG. 5 is a schematic view including the inspection unit 6 and is a side view seen from the + Y direction of FIG.
The inspecting unit 6 inspects the ink ejection state of the nozzles 24, and specifically, detects mainly missing dots that occur when ink is not ejected from the nozzles 24.
As shown in FIG. 5, the inspection unit 6 includes an inspection ejection unit 61 and an inspection scanner 62 (imaging unit).

The inspection ejection unit 61 is for ejecting ink from the nozzles 24 of the ejection head 20 for inspection, and is disposed on the −X direction side of the suction table 33a.
The inspection ejection unit 61 includes, for example, a flexible film whose surface is an ink ejection area, a winding device that winds up the area of the flexible film on which the ink is ejected, and an area of the flexible film on which the ink is not ejected. And a delivery device for delivering the product.
In this flexible film, the width of the exposed area (area where ink can be ejected) is set to about several times the width of the ejection head 20, and the length of the exposed area is set to be about the same as the head unit 21.
In other words, the inspection ejection unit 61 can linearly arrange the ink ejected from each of the ejection heads 20 arranged shifted in the Y direction for each nozzle row 24A, and further includes the inspection ejection unit 61. By displacing in the X direction, the operation of ejecting ink from all the nozzles 24 can be repeated a plurality of times.
In addition, as a flexible film, the flexible film which consists of polyethylene terephthalate (PET), polyethylene (PE), polycarbonate (PC) etc. can be used, for example.

Further, as shown in FIG. 5, the inspection ejection unit 61 is movable in the horizontal direction by a slide device 63 that is movable in the X direction.
In the present embodiment, the slide device 63 is configured to be able to move the inspection ejection unit 61 from a position below the ejection head 20 to a position below the inspection scanner 62.

The inspection scanner 62 is further spaced apart from the suction table 33a in the −X direction than the inspection ejection unit 61, and is fixedly disposed in an external region of the movable range of the ejection head 20 (head unit 21). Yes.
Then, the inspection scanner 62 images the ink ejected to the inspection ejecting unit 61 in the external region of the movable range of the ejection head 20.

As described above, in the liquid droplet ejecting apparatus 1 according to the present embodiment, the inspection ejection unit 61 can be moved horizontally, and the inspection scanner 62 is fixed.
Then, ink is ejected from the ejection head 20 to the inspection ejection unit 61 disposed below the ejection head 20, and then the ejected ink is imaged by moving the ejection head 20 to the inspection scanner 62. .

  Returning to FIG. 1, the control unit 60 controls the entire operation of the liquid droplet ejecting apparatus 1 of the present embodiment. For example, the control unit 60 controls the X-axis scanning mechanism 11 to perform main scanning in the X-axis direction, and controls the Y-axis scanning mechanism 42 to perform sub-scanning in the Y-axis direction. ing. Further, in addition to the scanning control by the control of the X-axis scanning mechanism 11 and the Y-axis scanning mechanism 42, the ejection control from the nozzles 24 (nozzle row 70) at the time of each scanning is performed. That is, it also has a function as an injection control unit that controls the injection corresponding to each scan.

In the droplet ejecting apparatus 1 according to the present embodiment, the control unit 60 performs control so that the ejection pitch of the ink for the inspection ejection unit 61 of the inspection unit 6 is wider than the ejection pitch for the recording medium 10.
More specifically, in the present embodiment, the ejection head 20 (head unit 21) is movable in a scanning direction (scanning direction: Y direction) that is a linear direction on a horizontal plane, and an inspection ejection unit The ejection pitch for 61 is adjusted so as to be wider than the ejection pitch for the recording medium 10 in the scanning direction.
For example, as shown in FIG. 6A, when the ejection pitch for the recording medium 10 is a pitch corresponding to 360 dpi in the X direction and a pitch corresponding to 720 dpi in the Y direction, As shown in FIG. 6B, the injection pitch for 61 is a pitch corresponding to 360 dpi in the X direction and a pitch corresponding to 360 dpi in the Y direction. The injection pitch for the inspection injection unit 61 may not be a pitch corresponding to 360 dpi, but may be a pitch corresponding to 180 dpi.

In order to eject ink onto the recording medium 10 by the droplet ejecting apparatus 1 having such a configuration and print a desired image, first, the control unit 60 causes the X-axis drive motor and the Y-axis in the X-axis scanning mechanism 11 to be printed. The Y-axis drive motor in the scanning mechanism 42 is driven to sequentially change the relative position between the ejection head 20 and the recording medium 10 on the suction table 33a. In parallel with such scanning control, a drive waveform (drive voltage) is applied to the piezoelectric element 59 of the ejection head 20 to drive it, and the ultraviolet curable ink S is ejected from each nozzle row 70 of the ejection head 20. Inject toward 10 and land.
Similarly, when detecting the ink ejection state of the nozzles 24, the ultraviolet curable ink S is ejected and landed toward the inspection unit 6 (inspection ejection unit 61). Then, the control unit 60 moves the inspection ejection unit 61 by the slide device 63 so that the ink that has landed on the inspection ejection unit 61 is imaged by the inspection scanner 62, and the ink ejection state is determined based on the imaging data. to decide.

In the droplet ejecting apparatus 1 (droplet ejecting method) according to the present embodiment, the ejection pitch of the ultraviolet curable ink S with respect to the inspection unit 6 is set to be greater than the ejection pitch of the ultraviolet curable ink S with respect to the recording medium 10. It is also wide.
For this reason, the spray pitch of the ultraviolet curable ink S to the inspection unit 6 is wider than the spray pitch of the ultraviolet curable ink S to the recording medium 10.
For this reason, it can suppress that the ultraviolet curable ink S sprayed to the test | inspection part 6 contacts with the adjacent ultraviolet curable ink S after landing, and when abnormality exists in an ink ejection state, the cause of abnormality The nozzle which becomes can be specified easily.
Therefore, according to the liquid droplet ejecting apparatus 1 of the present embodiment, it is possible to reliably determine the ink ejecting state of the nozzle.

Further, in the liquid droplet ejecting apparatus 1 of the present embodiment, the ejecting head 20 is movable in a scanning direction that is a linear direction on a horizontal plane, and the ejecting pitch in the scanning direction with respect to the inspection unit 6 is set with respect to the recording medium 10. It is wider than the spray pitch of the ultraviolet curable ink S.
For this reason, even when the ejection pitch in the scanning direction is widened in the inspection unit 6, there are a plurality of nozzle rows 70, and the plurality of nozzles 24 are adjacent to each other in the scanning direction, the ink ejection state of each nozzle 24 is ensured. It becomes possible to judge.

Furthermore, in the liquid droplet ejecting apparatus 1 of the present embodiment, the ejecting pitch in the direction perpendicular to the scanning direction with respect to the inspection unit 6 (sub-scanning direction: X direction) is set to be larger than the ejecting pitch of the ultraviolet curable ink S with respect to the recording medium 10. It is preferable to make it wide.
Specifically, as shown in FIG. 7, the nozzle 24 forming one nozzle row 70 can eject the ultraviolet curable ink S one by one, thereby widening the ejection pitch in the X direction. Then, after the inspection ejection unit 61 and the ejection head 20 are relatively moved in the X direction, the ultraviolet curable ink S is ejected from the nozzles 24 that did not eject the ultraviolet curable ink S in the previous ejection. Also in this case, since the ultraviolet curable ink S is ejected from the nozzle 24 by skipping one, the ejection pitch in the X direction can be widened.
Thus, by widening the ejection pitch in the X direction in the inspection unit 6, even when the nozzles 24 are arranged at a narrow pitch in the X direction, the ink ejection state of each nozzle 24 can be reliably determined. Is possible.

Further, in the droplet ejecting apparatus 1 of the present embodiment, it is preferable to control so that the landing diameter of the ultraviolet curable ink S on the inspection unit 6 is larger than the landing diameter of the ultraviolet curable ink S on the recording medium 10. .
In this way, by increasing the landing diameter of the ultraviolet curable ink S in the inspection unit 6, the threshold value for extracting data indicating the landing area of the ultraviolet curable ink S from the imaging data acquired by the inspection scanner 62 is set. It is possible to increase the size, and it is possible to suppress erroneous detection of foreign matters such as dust adhering to the inspection unit 6 as the ultraviolet curable ink S.

Increasing the landing diameter of the ultraviolet curable ink S can be realized by increasing the amount of injection at one time. Also, for example, as shown in FIG. 8, the inspection unit 6 (inspection injection unit 61). ) Can be realized by spraying the ultraviolet curable ink S a plurality of times at the same position.
In order to increase the injection amount once, it is necessary to change the drive voltage in accordance with the injection amount. However, in the case where the ultraviolet curable ink S is injected a plurality of times at the same position of the inspection unit 6, the ultraviolet curable type is used. The landing diameter can be easily adjusted by the number of ejections of the ink S.
For example, in the liquid droplet ejecting apparatus 1 of the present embodiment, since the ejecting head 20 reciprocates in the scanning direction, the ultraviolet curable ink S is ejected by each of the forward movement of the ejecting head 20 and the backward movement of the ejecting head 20. By doing so, the ultraviolet curable ink S can be easily ejected to the same location.

Note that when the ultraviolet curable ink S is ejected a plurality of times to the same position of the inspection unit 6, for example, it is conceivable to irradiate ultraviolet rays every time the ultraviolet curable ink S is ejected at one ejection location.
In such a case, the subsequent ink is ejected in a state where the ultraviolet curable ink S ejected earlier is already cured.
Since the surface of the cured ultraviolet curable ink S exhibits liquid repellency, the ultraviolet curable ink S ejected later rises, and the height of the ultraviolet curable ink S can be increased.
Therefore, the appearance of the cured ultraviolet curable ink S can be made darker in the inspection unit 6, and it is easy to extract data indicating the landing area of the ultraviolet curable ink S from the imaging data at the time of density detection. Become.

Further, when the presence or absence of the ultraviolet curable ink S is detected by density detection, the moving speed of the ejection head 20 when the ultraviolet curable ink S is ejected to the inspection unit 6 is determined, and the ultraviolet curable ink S is applied to the recording medium 10. A configuration is adopted in which control is performed to make the speed higher than the moving speed of the ejection head 20 when ejecting the gas.
As a result, the moving speed of the ejection head 20 when ejecting the ultraviolet curable ink S to the inspection unit 6 is increased, and therefore the time until the ultraviolet curable ink S is irradiated with ultraviolet rays can be shortened. The ultraviolet curable ink S can be quickly cured. Therefore, the appearance of the cured ultraviolet curable ink S can be made darker in the inspection unit 6, and it is easy to extract data indicating the landing area of the ultraviolet curable ink S from the imaging data at the time of density detection. Become.

Further, when the ultraviolet curable ink S is ejected a plurality of times to the same position of the inspection unit 6, for example, after the ultraviolet curable ink S is ejected a plurality of times to the same position of the inspection unit 6, It is also possible to irradiate with ultraviolet rays.
In such a case, the subsequent ink is ejected in a state where the previously ejected ink is not cured.
For this reason, it is possible to easily increase the landing diameter of the ultraviolet curable ink S in the inspection unit 6, and when detecting the presence or absence of the ultraviolet curable ink S based on the size of the landing diameter, the ultraviolet curable ink is detected from the imaging data. It becomes easy to extract data indicating the landing area of S.

When the presence or absence of the ultraviolet curable ink S is detected based on the size of the landing diameter, the moving speed of the ejection head 20 when the ultraviolet curable ink S is ejected to the inspection unit 6 is determined by the ultraviolet curing on the recording medium 10. It is preferable to make it slower than the moving speed of the ejection head 20 when ejecting the mold ink S.
As a result, the moving speed of the ejection head 20 when ejecting the ultraviolet curable ink S onto the inspection unit 6 is slowed down, so that the time until the ultraviolet curable ink S is irradiated with ultraviolet light becomes longer and the ultraviolet curable ink is cured. The mold ink S can be widely spread and wetted. For this reason, it is possible to easily increase the landing diameter of the ultraviolet curable ink S in the inspection unit 6, and when detecting the presence or absence of the ultraviolet curable ink S based on the size of the landing diameter, the ultraviolet curable ink is detected from the imaging data. It becomes easy to extract data indicating the landing area of S.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the said embodiment. Various shapes, combinations, and the like of the constituent members shown in the above-described embodiments are examples, and various modifications can be made based on design requirements and the like without departing from the spirit of the present invention.

  For example, in the above embodiment, the liquid droplet ejecting apparatus of the present invention is applied to a printing apparatus that performs printing on a continuous long recording medium. However, the present invention is not limited thereto, The object to be ejected is not long but can be a rectangular substrate. Moreover, as such a board | substrate, a glass substrate can also be made into object besides resin mentioned above.

  In the above embodiment, the irradiation device 80 is applied to a serial type printing device that is fixed to the sub-carriage 28 or the unit plate 23 and scans the head unit 21 in the X-axis direction by the X-axis scanning mechanism 11. The invention is not limited to this, and a head carriage in which the length of the head carriage 22 is equal to or longer than the length in the width direction of the printing area of the recording medium 10, a so-called line head, may be employed. Further, an apparatus configuration is adopted in which the length of the head carriage 22 is equal to or less than the length in the width direction of the print area of the recording medium 10 and the head carriage 22 is fixed and the recording medium 10 is scanned in the X-axis direction. Also good. Further, an irradiation device having a length equal to or greater than the length in the width direction of the printing area of the recording medium 10, a so-called line irradiation device may be employed.

  In the above embodiment, the case where the present invention is applied to a droplet ejecting apparatus mainly for industrial use has been described. However, the present invention can also be applied to a printer for consumer use.

  DESCRIPTION OF SYMBOLS 1 ... Droplet injection apparatus, 10 ... Recording medium (jetting object), 6 ... Inspection part, 61 ... Inspection injection part, 62 ... Inspection scanner, 20 ... Injection head, 21 ... Head Unit, 24 ... Nozzle, 60 ... Control, S ... UV curable ink (ink)

Claims (10)

A droplet ejecting apparatus comprising: an ejecting head having a nozzle that ejects ink to an ejected object; and an inspection unit that receives the ink outside the ejected object and inspects an ink ejecting state of the nozzle. And
A droplet ejecting apparatus that performs control to make the ejection pitch of the ink to the inspection unit wider than the ejection pitch of the ink to the ejection target. The ejection head is movable in a scanning direction which is a linear direction in a horizontal plane;
2. The droplet ejecting apparatus according to claim 1, wherein control is performed so that the ejection pitch in the scanning direction with respect to the inspection unit is wider than the ejection pitch of the ink with respect to the ejection target. The ejection head is movable in a scanning direction which is a linear direction in a horizontal plane;
3. The droplet according to claim 1, wherein control is performed to make the ejection pitch of the ink in a direction orthogonal to the scanning direction with respect to the inspection unit wider than the ejection pitch of the ink with respect to the ejection target. Injection device.   The droplet ejecting apparatus according to claim 1, wherein control is performed to make the ink landing diameter of the inspection portion larger than the ink landing diameter of the ejected object.   The droplet ejecting apparatus according to claim 4, wherein control is performed to increase the landing diameter by ejecting ink a plurality of times to the same position of the inspection unit. The ink is an ultraviolet curable ink that is cured by ultraviolet irradiation,
The liquid droplet ejecting apparatus according to claim 5, wherein when the ink is ejected a plurality of times to the same position of the inspection unit, control is performed to irradiate the ink with ultraviolet rays each time the ink is ejected. The ink is an ultraviolet curable ink that is cured by ultraviolet irradiation,
The droplet ejecting apparatus according to claim 5, wherein after the ink is ejected a plurality of times at the same position of the inspection unit, the ink is controlled to be irradiated with ultraviolet rays. The ink is an ultraviolet curable ink that is cured by ultraviolet irradiation,
The control is performed so that the moving speed of the ejecting head when ejecting the ink to the inspection unit is slower than the moving speed of the ejecting head when ejecting the ink onto the ejected object. Item 8. The droplet ejection device according to any one of Items 1 to 7. The ink is an ultraviolet curable ink that is cured by ultraviolet irradiation,
The control is performed so that the movement speed of the ejection head when ejecting the ink to the inspection unit is faster than the movement speed of the ejection head when ejecting the ink onto the ejection target. Item 8. The droplet ejection device according to any one of Items 1 to 7. The nozzles eject ink onto the ejected object from nozzles formed on the ejecting head with respect to the ejected object, and eject the ink onto an inspection unit provided outside the ejected object. A droplet ejection method for inspecting the ink ejection state of
A droplet ejecting method, wherein the ink ejecting pitch with respect to the inspection unit is wider than the ink ejecting pitch with respect to the ejected object.

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