JP5786415B2 - Drawing method and drawing apparatus - Google Patents

Description

  The present invention relates to a drawing method and a drawing apparatus.

  A drawing method using an ultraviolet curable ink (referred to as UV ink) that is excellent in light resistance and water resistance and can be used for an outdoor poster or the like has attracted attention. When UV ink is printed by the inkjet method, the landing diameter of the ink is important in order to obtain a desired image resolution. In order to appropriately control the landing diameter, there are a method of performing a liquid repellent treatment on the surface of the substrate to be drawn, a method of forming a base layer having a uniform film thickness, and the like. As a method for forming the undercoat layer, a wet undercoat layer is formed on the surface of the substrate to be drawn, and while the undercoat layer is wet, drawing is further performed with wet ink droplets. There has been proposed a drawing method for drying and curing (see, for example, Patent Document 1).

Special Table 2002-530229

  In such a drawing method according to Patent Document 1, since the drawing ink is ejected when the underlayer is in a wet state, there are irregularities at the interface with the drawing ink of the underlayer, and as a result, the surface of the drawing layer is present. However, there is a problem that unevenness appears and a uniform drawing layer cannot be formed, and drawing quality such as desired image resolution is deteriorated.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

Application Example 1 A drawing method according to this application example includes a step of discharging a base layer ink to a substrate to be drawn to form a base layer, a step of curing the base layer, and a step of curing the base layer And a step of discharging drawing ink on the surface and drawing.
Here, the base layer ink forms a background color such as clear ink, black ink, and white ink, and the drawing ink is color ink that forms characters, images, and the like.

  According to this application example, the drawing ink is ejected after the underlayer is cured. The foundation layer is leveled into a uniform layer without irregularities in the process from ejection of the foundation layer ink to curing. Accordingly, since the drawing ink is landed on a uniform surface having no irregularities, the diameter of the drawing layer can be reduced, and high image resolution with drawing quality can be realized.

  Application Example 2 In the drawing method according to the application example, the step of curing the base layer is performed while the ink discharge position moves from the discharge end position of the base layer ink to the discharge start position of the drawing ink. Are preferred.

  In this way, since the underlying layer is cured before the drawing ink is ejected, high image resolution with drawing quality can be realized. In addition, by performing the curing process while the ink ejection position moves from the base layer ink ejection end position to the drawing ink ejection start position, efficient rendering can be performed without time loss for the curing process. There is an effect that can be.

  Application Example 3 In the drawing method according to the application example, it is preferable that the drawing ink is discharged and the discharged region is cured in the course of the step of discharging the drawing ink.

  In some cases, the drawing ink is ejected by reciprocating the ink ejection position. In such a case, for example, the region where the drawing ink is ejected in the forward path is cured during the return path, and the region where the drawing ink is ejected during the return path is cured during the forward path, thereby performing the ejection. The drawn ink can be cured to improve the drawing quality and achieve high image resolution.

  Application Example 4 In the drawing method according to the application example described above, it is preferable that the step of curing the base layer starts after a predetermined time has elapsed since the discharge of the base layer ink.

  For example, if the curing process is started 1 second after the formation of the underlayer, the substrate is cured when the underlayer is made uniform, so that a uniform underlayer without unevenness can be formed.

  Application Example 5 A drawing apparatus according to this application example includes a base layer inkjet head that discharges base layer ink, a drawing inkjet head that discharges drawing ink, and a curing unit that cures at least the base layer ink. A carriage unit, a driving unit that moves the carriage unit, and / or a driving unit that moves the substrate to be drawn, the underlayer inkjet head, the drawing inkjet head, and the curing unit. Are arranged in a direction perpendicular to the feeding direction of the drawing base material or in the feeding direction of the drawing base material.

Here, the base layer ink forms a background color such as a clear ink, a black ink, and a white ink, and the drawing ink is a color ink that forms characters, images, and the like.
According to this application example, since the underlayer ink jet head, the drawing ink jet head, and the curing unit are arranged in the carriage unit, the underlayer ink ejection / curing / drawing ink ejection is controlled in an arbitrary order and timing. can do. Thus, drawing ink can be discharged at an appropriate timing after the base layer is cured. Therefore, the underlying layer is leveled in a uniform layer without unevenness in the process from ejection to curing, and the drawing ink is landed on a uniform surface without unevenness. High quality image resolution can be achieved.

Further, if the underlayer inkjet head, the drawing inkjet head, and the curing means are arranged in a direction orthogonal to the feeding direction of the drawing base material, the carriage unit is set to the drawing base material feeding direction. It is possible to cope with serial scanning that can move in the orthogonal direction and move in the feeding direction.
Further, if the base layer ink jet head, the drawing ink jet head, and the curing means are arranged in the feeding direction of the drawing base material, the position of the carriage unit is fixed and the drawing base material is moved. It is possible to cope with lateral scanning.

  Application Example 6 In the drawing apparatus according to the application example described above, it is preferable that at least the base layer ink is an ultraviolet curable ink, and the curing unit is an ultraviolet lamp.

  Ultraviolet curable ink (hereinafter abbreviated as UV ink) does not contain volatile organic compounds, and is effective as an undercoat layer for color drawing on transparent sheets, etc., because the ink is instantly cured by ultraviolet irradiation. It is. If, for example, an LED (Light Emitting Diode) (however, a wavelength in the ultraviolet region) is used as the ultraviolet lamp, it can be reduced in size and weight, can be easily attached to the carriage unit, and power consumption can be reduced.

1A and 1B show an example of a drawing apparatus according to Embodiment 1, in which FIG. 1A is a plan view, and FIG. It is a plane explanatory view showing typically the main process of the drawing method concerning Embodiment 1, (a) is a clear printing process, and (b) is a clear layer hardening process. FIG. 5 is an explanatory diagram schematically showing the arrangement of color heads, clear heads, and LEDs of a drawing apparatus according to Example 1 of Embodiment 2. FIG. 3 is an explanatory plan view schematically showing main steps of the drawing method according to Embodiment 1, wherein (a) is a clear ink discharge step, (b) is a clear layer curing step, and (c) is a color ink discharge step. FIG. 6 is an explanatory diagram schematically showing the arrangement of color heads, clear heads, and LEDs of a drawing apparatus according to Embodiment 2. FIG. 9 is a plan explanatory view schematically showing main steps of a drawing method according to Example 2, wherein (a) is a clear ink discharge step, (b) is a clear layer curing step, and (c) is a forward color ink discharge step. , (D) is a return color ink ejection process, and (e) is a second forward color ink ejection process.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The drawing apparatus described below is for drawing a desired image or the like by discharging drawing ink after forming a base layer on a drawing substrate. In the following description, the feed direction of the substrate to be drawn (hereinafter referred to as a workpiece W) is the X-axis direction, the direction orthogonal to the X-axis direction is the Y-axis direction, the X-axis direction, and the Y-axis direction Is defined as the Z-axis direction. First, the configuration of the drawing apparatus will be described.
(Embodiment 1)
(Drawing device)

  1A and 1B show an example of a drawing apparatus according to Embodiment 1, wherein FIG. 1A is a plan view and FIG. 1B is a front view. In the present embodiment, an explanation will be given by exemplifying a method of removing material in a so-called roll-to-roll format. The drawing device 1 is disposed on a machine base 2, a feeding device 3 that feeds out a long workpiece W wound in a roll shape, a winding device 4 that winds up a printed workpiece W, and the machine base 2. The workpiece stage 5 that sucks and sets the supplied workpiece W, the X-axis table 7 that extends in the X-axis direction and intermittently feeds the workpiece W in the X-axis direction via the workpiece stage 5, and the X-axis table 7 has a Y-axis table 8 spanned in the Y-axis direction so as to straddle 7, and a plurality of inkjet heads 50 that discharge ink and print on the workpiece W, and are movably mounted on the Y-axis table 8. The carriage unit 9 is provided, and a work holding means 60 is provided on the downstream side in the X-axis direction of the work stage 5 and clamps and fixes the work W.

  In the present embodiment, in order to perform the printing of the underlayer and the color drawing, corresponding inkjet heads are provided side by side in the Y-axis direction. The underlayer is, for example, a clear layer, a background color such as black or white, and the underlayer described below exemplifies a case where a clear layer is printed. Therefore, the inkjet head 50 is a clear inkjet head 51 (hereinafter referred to as the clear head 51: see FIG. 2) as a base layer inkjet head, and a color inkjet head 52 (hereinafter referred to as a color head 52) as a drawing inkjet head. 2).

  Further, the drawing apparatus 1 includes a maintenance device 11 including a suction unit that forcibly discharges ink from the clear head 51 and the color head 52 and a wiping unit that wipes the nozzle surface, and a control device 13 that performs overall control of the drawing apparatus 1. It is equipped with. The maintenance device 11 is disposed in a maintenance area that is deviated in the Y-axis direction from the printing area where the X-axis table 7 and the Y-axis table 8 intersect, and maintenance of the clear head 51 and the color head 52 facing the maintenance area is performed. I do.

  In the drawing apparatus 1, after the work W fed by the feeding apparatus 3 is attracted by the work stage 5, the work W is intermittently fed (sub-scanned) in the X-axis direction via the work stage 5 by the X-axis table 7. Then, printing is performed by ejecting ink from the clear head 51 and the color head 52 while reciprocating (main scanning) the carriage unit 9 with respect to the print area of the work W held by suction.

  The feeding device 3 is disposed on the upstream side in the feed direction (X-axis direction) of the workpiece W from the machine base 2. The feeding device 3 includes a feeding reel 21 that winds the workpiece W in a roll shape, a feeding motor 22 that feeds and rotates the feeding reel 21, and a bent workpiece W bent in a “V” shape in the Z-axis direction. A feeding-side buffer mechanism 23 that applies a light back tension to the workpiece W.

  Further, as shown in FIG. 1B, the feeding-side buffer mechanism 23 includes a feeding-side dancer roller 23a that can move in the Z-axis direction so as to always apply a back tension to the workpiece W, and a feeding-side dancer roller 23a. It has a feeding side guide roller 23b provided on each of the upstream side and the downstream side, and a pair of upper and lower feeding side sensors 23c for detecting the position of the feeding side dancer roller 23a in the Z-axis direction. The feeding side guide roller 23b on the upstream side of the paper feed is a nip roller.

  The length of the workpiece W held in the feeding-side buffer mechanism 23 is set to be longer than the moving distance of the workpiece stage 5. In the present embodiment, in order to maintain the length of the workpiece W, the feeding motor 22 is driven by the detection of the upper limit side feeding sensor 23c, and the feeding motor 22 is stopped by the detection of the lower limit side feeding sensor 23c. It is like that. With such a structure, a necessary amount of workpieces W can be fed out. Further, when the drawing operation is repeated a plurality of times, the work W is wound around the supply reel 21 again.

  The winding device 4 is disposed downstream of the machine base 2 in the feed direction of the workpiece W (X-axis direction). The winding device 4 uses a winding motor 25 for winding the workpiece W in a roll shape, a winding motor 25 for winding and rotating the winding reel 24, and “V” the wound workpiece W in the Z-axis direction. And a winding-side buffer mechanism 26 for bending the workpiece W and applying a light forward tension to the workpiece W.

  As shown in FIG. 1B, the winding-side buffer mechanism 26 includes a winding-side dancer roller 26a that can move in the Z-axis direction so as to always apply a forward tension to the workpiece W, and a winding-side dancer roller 26a. A winding side guide roller 26b provided on each of the upstream side and the downstream side, and a pair of upper and lower winding side sensors 26c for detecting the position of the winding side dancer roller 26a in the Z-axis direction. The feeding-side guide roller 23b on the downstream side of the workpiece W is a nip roller.

  The take-up side buffer mechanism 26 drives the take-up motor 25 by the detection of the lower-end side take-up sensor 26c so that the workpiece W having a predetermined length can be maintained in the same manner as the feed-out side buffer mechanism 23. The take-up motor 25 is stopped by detection of the take-up side sensor 26c. According to such a structure, it is possible to take up a necessary amount of the work W without being affected by the roll diameter of the take-up reel 24. As a result, the work W sent downstream can be absorbed by the take-up buffer mechanism 26, so that the discharged material can be discharged without taking up the sent work W around the take-up reel 24. Can do. Further, the work W can be wound around the take-up reel 24 without applying extra tension to the work W on the work stage 5.

  The work stage 5 has a plurality of holes (not shown) on the surface, a stage main body 27 that sucks the work W sent from the feeding device 3, and an upstream of the work W of the stage main body 27 in the conveyance (X-axis) direction. A feed roller 28 attached to the end portion and a feed roller 29 attached to the downstream end portion of the stage main body 27 in the conveyance (X-axis) direction of the workpiece W are provided. Although not described in detail, the plurality of holes formed in the stage main body 27 communicate with a vacuum suction facility and a compressed air supply facility that are not shown.

  The work stage 5 is intermittently fed in the X-axis direction (from the upstream side to the downstream side) by the X-axis table 7 while the work W is attracted by the stage body 27. In this embodiment, since drawing may be repeated a plurality of times in the drawing area, when the downstream end position (discharge end position) at which drawing for the drawing area ends is reached, the X-axis table 7 causes the upstream end position (discharge start position). Move back to).

  The feeding roller 28 and the feeding roller 29 are each constituted by a nip roller that freely rotates, and are arranged side by side in the X-axis direction. The feed roller 28 and the feed roller 29 are each of a lowered position where the upper part is substantially flush with the upper surface of the stage body 27, and a raised position slightly elevated (several millimeters) from the lowered position. It can be moved up and down. The lifting mechanism of the feeding roller 28 and the feeding roller 29 is preferably composed of a cylinder (either air pressure or hydraulic pressure), a motor, a rack and pinion, and the like.

  The workpiece W is transferred to the upper surface of the stage main body 27 while being sandwiched between the feeding roller 28 and the feeding roller 29. By moving the feeding roller 28 and the sending roller 29 to the lowered position, the work W (recording area) can be sucked and held on the upper surface of the stage main body 27, and the sucking and holding is canceled (vacuum suction is stopped). Then, the compressed air is supplied between the workpiece W and the stage main body 27, and the workpiece W is lifted slightly by moving to the raised position. This makes it possible to remove or supply material from the upper surface of the stage main body 27 without applying excessive tension to the workpiece W. In addition, since the recording area is separated (floated) from the work stage 5, it is possible to remove the material without causing scratches such as scratches on the work W.

  The feeding roller 28 and the feeding roller 29 arranged at the lowered position are arranged in the X-axis direction and at substantially the same surface position as the upper surface of the stage main body 27. For this reason, the flatness of the workpiece W can be maintained not only in the region held by suction on the stage main body 27 but also from the position sandwiched between the feeding rollers 28 to the position sandwiched between the feeding rollers 29. That is, a wide drawing area can be secured. Moreover, when raising / lowering the feeding roller 28 and the sending roller 29, after raising / lowering one of the feeding roller 28 or the sending roller 29, it is preferable to start raising / lowering the other with a delay. As a result, when moving to the lowered position, the work W can be brought into close contact with the stage main body 27 so as to push out air between the work W and the stage main body 27, thereby ensuring good suction holding. it can.

  The X-axis table 7 is disposed on the machine base 2 and has a pair of X-axis guide rails 31 extending in the X-axis direction, and a motor drive that supports the work stage 5 slidably along the X-axis guide rails 31. X-axis slider 32. The X-axis table 7 stops when the carriage unit 9 (the clear head 51 and the color head 52) moves forward (or backward), and moves the workpiece W by the print width by X until the next backward movement (or forward movement). Send to the downstream side in the axial direction. In other words, after the X-axis table 7 performs print scanning of the carriage unit 9, the X-axis table 7 intermittently feeds (feed feed) the work stage 5 (work W) by a distance corresponding to the printed width. The drive system is preferably composed of a linear motor, a motor, a ball screw mechanism, and the like.

  The Y-axis table 8 includes a pair of Y-axis guide rails 34 laid across the machine base 2 in the Y-axis direction, a bridge plate 35 in which the carriage unit 9 is suspended, and the bridge plate 35 in the Y-axis direction. And a motor-driven Y-axis slider 36 that is slidably supported. The Y-axis table 8 reciprocates the ink-jet head 50 in the Y-axis direction during printing via the carriage unit 9 and causes the ink-jet head 50 to face the maintenance device 11. The drive system is preferably composed of a linear motor, a motor and a ball screw mechanism, a mechanism using a belt and a pulley, and the like.

  The carriage unit 9 includes a carriage body 43 that is suspended from the bridge plate 35, and a head unit 44 that is suspended from the carriage body 43 and includes a plurality of clear heads 51 and color heads 52. The carriage body 43 incorporates a mechanism (not shown) that rotates the head unit 44 by θ degrees. The head unit 44 is configured by mounting a plurality of clear heads 51 and a color head 52 on a head plate (not shown), and ultraviolet irradiation lamps as curing means are provided at both ends in the Y-axis direction of the head plate. Is arranged. In this embodiment, a pair of LED lamps 71 and 72 (see FIG. 2) are mounted as ultraviolet irradiation lamps. That is, the LED lamps 71 and 72 are disposed on both sides of the inkjet head 50 in the Y-axis direction. The LED lamps 71 and 72 are made up of an assembly of a plurality of light source elements. The LED lamps 71 and 72 irradiate light having a wavelength in the ultraviolet region.

A large number of ejection nozzles (not shown) are opened in each of the clear head 51 and the color head 52, and a piezoelectric element corresponding to each ejection nozzle is configured in the head body, and a voltage is applied to the piezoelectric element. Then, a clear ink droplet or a color ink droplet is ejected from the ejection nozzle.
(Drawing method)

Next, a drawing method using the drawing apparatus of the first embodiment will be described.
FIG. 2 is an explanatory plan view schematically showing main steps of the drawing method according to the first embodiment. Here, the case of serial scanning will be described as an example. The clear head 51 and the color head 52 are arranged in parallel in the Y-axis direction, and LED lamps 71 and 72 (shown simply as LEDs in the figure) are arranged on both sides of the clear head 51 and the color head 52 in the Y-axis direction. These are interlocked with the movement of the carriage unit 9. That is, it reciprocates in the Y axis direction. Further, the workpiece W moves in the X-axis direction.

  FIG. 2A shows a clear layer forming step, and FIG. 2B shows a clear layer curing step. First, as shown in FIG. 2A, the clear ink is discharged while moving the clear head 51 in the Y-axis direction in conjunction with the movement of the carriage unit 9 from the print start position (discharge start position: START). The color head 52 does not discharge, and the LED lamps 71 and 72 are in an OFF (no light irradiation) state. When the work W reaches the print end position (discharge end position: END), the clear ink discharge from the clear head 51 is stopped. In this way, the clear layer is printed.

  Subsequently, as shown in FIG. 2B, the clear layer is cured. Here, the ink discharge by the clear head 51 and the color head 52 is stopped, and the work W is moved from the print end position (discharge end position: END) to the print start position (discharge start position: START). The LED lamps 71 and 72 are turned on (ON) while reciprocating in the Y-axis direction in conjunction with the movement, and the clear layer is cured. The light irradiation timing from the LED lamps 71 and 72 is more preferably, for example, 1 second after a predetermined time has elapsed since the end of clear ink ejection. At this time, as long as the irradiation area of the LED lamps 71 and 72 can irradiate the entire width direction of the workpiece W, both of them may be lit or one of them may be turned off.

  When the work W reaches the print start position (discharge start position: START), the color ink discharge is started. This will be described with reference to FIG. Color ink is discharged from the printing start position (discharge start position: START) while moving the color head 52 in the Y-axis direction in conjunction with the movement of the carriage unit 9, and drawing is started. At this time, the clear head 51 and the LED lamps 71 and 72 are turned OFF, and the work W is moved to the print end position (discharge end position: END).

  Note that when discharging color ink, the LED lamp 71 or the LED lamp 72 may be turned on (ON) so as to cure the discharged color ink layer, or when reciprocating in the X-axis direction for drawing. The LED lamp 71 or the LED lamp 72 may be alternately turned on (ON) so as to cure the drawn color ink layer.

  Further, the carriage unit 9 may be moved in the Y-axis direction and also moved in the X-axis direction. In such a case, the position of the workpiece W is fixed. The carriage unit 9 can be controlled in combination with moving the workpiece W in the X-axis direction and moving the workpiece W in the X-axis direction.

  According to the first embodiment described above, the color ink for drawing is ejected after the clear layer that is the base layer is cured. The clear layer is leveled into a uniform layer without irregularities in the process from ejection to curing. Therefore, since the color ink can be landed on the surface of the uniform underlayer without unevenness, the landing diameter of the color ink can be reduced, and high image resolution with drawing quality can be realized.

  Also, since the clear layer is cured before the color ink is ejected, it is possible to realize high image resolution with drawing quality. Further, by performing the curing process while the ink ejection position moves from the clear ink ejection end position to the color ink ejection start position, efficient drawing can be performed without time loss for performing the curing process. There is an effect that can be done.

S4
In addition, the step of curing the clear layer is cured when the surface of the clear layer is made uniform if the curing step is started after a predetermined time, for example, 1 second from the discharge of the clear ink. It is possible to form a uniform clear layer having no mist.

The clear ink is ultraviolet curable ink (UV ink), and the curing means uses LED lamps 71 and 72 as ultraviolet lamps. The UV ink does not contain a volatile organic compound, and the ink is instantly cured by irradiation with ultraviolet rays. Therefore, the UV ink is effective as a base layer for color drawing on a transparent sheet or the like. The LED lamp can be reduced in size and weight, can be easily attached to the carriage unit 9, and can reduce power consumption.
(Embodiment 2)

  Next, Embodiment 2 will be described. The drawing apparatus according to the first embodiment is a serial scanning method, whereas the second embodiment is characterized by a lateral scanning method. Since the overall configuration of the drawing apparatus is the same as that of the first embodiment (see FIG. 1) except for the arrangement configuration of the color head, the clear head, and the LED, the differences will be mainly described. A case where there is one LED will be described as Example 1, and a case where there are two LEDs will be described as Example 2.

  FIG. 3 is an explanatory diagram schematically illustrating the arrangement of the color head, the clear head, and the LED of the drawing apparatus according to the first embodiment. As shown in FIG. 3, the color head 52, the LED lamp 71 (shown as LED 71), and the clear head 51 are arranged in the X-axis direction and attached to the carriage unit 9. A discharge nozzle (not shown) provided in each of the color head 52 and the clear head 51 is formed across the width of the workpiece W. The workpiece W can reciprocate on the workpiece stage 5 in the X-axis direction.

Next, a drawing method using such a drawing apparatus will be described.
FIG. 4 is an explanatory plan view schematically illustrating main steps of the drawing method according to the first embodiment. (A) is a clear ink discharge step, (b) is a clear layer curing step, and (c) is a color ink discharge step (drawing step). In addition, the arrow in a figure represents the moving direction of the workpiece | work W. FIG.

  First, as shown in FIG. 4A, a clear ink is ejected to form a clear layer as a base layer. At this time, the ink of the color head 52 is not discharged (OFF), the LED lamp 71 is turned off (OFF), and the clear ink is discharged from the clear head 51. When the work W reaches the print end position (discharge end position: END) from the print start position (discharge start position: START), the clear ink discharge from the clear head 51 is stopped.

  Subsequently, as shown in FIG. 4B, the clear layer is cured. At this time, ink is not ejected by the clear head 51 and the color head 52 (both are OFF), the LED lamp 71 is turned on (ON), and the work W is moved from the print end position (discharge end position: END) to the print start position ( When returning to the discharge start position (START), the LED lamp 71 is turned off (OFF).

  In the step of curing the clear layer, it is preferable to start the curing step after a predetermined time, for example, 1 second from the end of the discharge of the clear ink, as in the first embodiment.

  Subsequently, as shown in FIG. 4C, color ink is discharged and drawing is performed. At this time, ink discharge by the clear head 51 is not performed (OFF), the LED lamp 71 is turned off (OFF), and the work W moves from the print start position (discharge start position: START) to the print end position (discharge end position: END). ) Color ink is ejected until reaching ().

Further, when discharging color ink, the LED lamp 71 may be turned on (ON) so as to cure the drawn color ink layer (drawing layer), and when drawing is performed by reciprocating the drawing process in the X-axis direction. Alternatively, the LED lamp 71 may be turned on (ON) so as to cure the drawn color ink layer.
Alternatively, the position of the workpiece W may be fixed and the carriage unit 9 may be reciprocated in the Y axis direction.

  Therefore, according to the drawing apparatus and the drawing method of Example 1, the same effects as those of Embodiment 1 can be obtained.

Next, Example 2 will be described. The second embodiment is characterized in that two LED lamps are provided. The overall configuration of the drawing apparatus is the same as that of the above-described first embodiment (see FIG. 1), and a description thereof will be omitted.
FIG. 5 is an explanatory diagram schematically illustrating the arrangement of the color head, the clear head, and the LED of the drawing apparatus according to the second embodiment. As shown in FIG. 5, in the second embodiment, the LED lamp 71, the color head 52, the LED lamp 72, and the clear head 51 are arranged in the X-axis direction and attached to the carriage unit 9. A discharge nozzle (not shown) provided in each of the color head 52 and the clear head 51 is formed across the width of the workpiece W. The workpiece W can reciprocate on the workpiece stage 5 in the X-axis direction.

Next, a drawing method using such a drawing apparatus will be described.
FIG. 6 is an explanatory plan view schematically illustrating main steps of the drawing method according to the second embodiment. (A) is a clear ink ejection process, (b) is a clear layer curing process, (c) is a color ink ejection process in the forward path (first time), (d) is a color ink ejection process in the backward path, and (e) is 2 This represents the color ink discharge process in the forward path. In addition, the arrow in a figure represents the movement method of the workpiece | work W. FIG.

  First, as shown in FIG. 6A, clear ink is ejected to form a clear layer as a base layer. At this time, the ink of the color head 52 is not discharged (OFF), the LED lamps 71 and 72 are turned off (OFF), and the clear ink is discharged from the clear head 51. When the work W reaches the print end position (discharge end position: END) from the print start position (discharge start position: START), the clear ink discharge from the clear head 51 is stopped.

  Subsequently, as shown in FIG. 6B, the clear layer is cured. At this time, ink is not ejected by the clear head 51 and the color head 52 (both are OFF), the LED lamp 71 is turned on (ON), and the work W is moved from the print end position (discharge end position: END) to the print start position ( When returning to the discharge start position (START), the LED lamp 71 is turned off (OFF). If it is desired to further strengthen the clear layer, the LED lamp 72 is turned on together with the LED lamp 71.

  Also in Example 2, the step of curing the clear layer is preferably started after a predetermined time, for example, 1 second from the discharge of the clear ink, as in Embodiment 1 described above.

  Subsequently, as shown in FIG. 6C, color ink is ejected to perform drawing. At this time, ink discharge by the clear head 51 is not performed (OFF), the LED lamp 72 is turned off (OFF), and the work W is moved from the print start position (discharge start position: START) to the print end position (discharge end position: END). The color ink is discharged until () is reached. The LED lamp 71 is turned on (ON) to cure the color layer (drawing layer) after discharging the color ink. If it is desired to further harden the clear layer before discharging the color ink, the LED lamp 72 is turned on (ON).

  Drawing by color ink ejection may be performed by reciprocating the work W several times, and the drawing method in that case will be described. The drawing process shown in FIG. 6C will be described as the first forward path, and FIG. 6D will be described as the return path. In the case of the return path, the work W is moved from the print end position (discharge end position: END) to the position to be drawn, and color ink is discharged to start drawing.

  At this time, ink discharge by the clear head 51 is not performed (OFF), the LED lamp 71 is lit (ON), and the work W is changed from the drawing start position (discharge start position) in the return path to the drawing end position (discharge end position) in the return path. The color ink is discharged until () is reached. The LED lamp 72 is turned off (OFF). Note that the LED lamp 72 is turned on (ON) when it is desired to further harden the drawing layer after discharging the color ink.

Again, color ink is ejected in the forward path for drawing (second forward path). As shown in FIG. 6E, the work W is moved from the drawing end position in the step shown in FIG. 6D to the drawing position, the color ink is discharged, and drawing is started. At this time, ink discharge by the clear head 51 is not performed (OFF), the LED lamp 72 is turned off (OFF), and the work W is moved from the third drawing start position (discharge start position) to the third drawing end position (discharge). Color ink is ejected and drawn until the end position :) is reached. The LED lamp 71 is turned on (ON), and the drawing layer after the color ink is discharged is cured. Note that the LED lamp 72 is turned on (ON) when it is necessary to further cure the drawing layer after discharging the color ink in the return path (see FIG. 6D).
Furthermore, when drawing is performed by repeatedly discharging color ink, the drawing may be repeated such as drawing the second recovery path and drawing the third forward path.

  Therefore, according to the drawing apparatus and the drawing method of the second embodiment, the same effects as those of the first embodiment can be obtained.

  Further, when drawing by discharging the color ink is performed a plurality of times by reciprocating the workpiece W, for example, the drawing layer after the color ink is discharged on the forward path is cured during the return path, and the drawing ink is returned on the return path. Curing of the drawing layer from which the ink is discharged is performed again during the forward path, whereby the discharged drawing ink is cured, drawing quality is improved, and high image resolution can be realized.

  W: Work as a drawing substrate, 5: Work stage, 51: Clear head, 52: Color head, 71, 72: LED lamp.

Claims (5)

A step of discharging a base layer ink to a drawing base material from a discharge start position on the drawing base material to a discharge end position , and forming a base layer;
Curing the underlayer;
Discharging drawing ink on the surface of the cured base layer and drawing,
Only including,
Performing the step of curing the underlayer while the ink discharge position moves from the discharge end position to the discharge start position;
A drawing method characterized by. During the process of discharging the drawing ink,
Discharging the drawing ink and curing the discharged region;
The drawing method according to claim 1 , wherein: The step of curing the underlayer starts after a predetermined time has elapsed since the ejection of the underlayer ink.
The drawing method according to claim 1 , wherein the drawing method is characterized in that: A base layer inkjet head for discharging the base layer ink;
A drawing inkjet head for discharging drawing ink;
A carriage unit provided with a curing means for curing at least the underlayer ink;
Driving means for moving the substrate to be drawn;
With
The underlayer inkjet head, the drawing inkjet head, and the curing means are arranged in a direction orthogonal to the feeding direction of the drawing base material ,
The base layer inkjet head discharges the base layer ink while the substrate to be drawn is moved from the discharge start position to the discharge end position with respect to the carriage unit by the driving unit,
The curing unit cures the base layer ink while the substrate to be drawn is moved from the discharge end position to the discharge start position with respect to the carriage unit by the driving unit,
The drawing ink jet head discharges the drawing ink while the drawing substrate is moved from the discharge start position to the discharge end position with respect to the carriage unit by the driving unit.
A drawing apparatus characterized by that. At least the base layer ink is an ultraviolet curable ink,
The curing means is an ultraviolet lamp;
The drawing apparatus according to claim 4 .

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