JP2010271345A - Apparatus and method for discharging droplet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and method for discharging droplets, capable of obtaining a required display image by improving the deposition accuracy of ink discharged from a droplet discharge head to prevent the color mixture or color unevenness of pixel and has superior efficiency of production. <P>SOLUTION: The apparatus has a droplet discharge head 9, a work stage 6 mounting a substrate on which a functional liquid discharged from a plurality of nozzles is deposited and a control means 8 for controlling the relative movement of each droplet discharge head 9 and the substrate and the discharge action of each droplet discharge head 9. The control means 8 controls the relative movement of each droplet discharge head 9 to the substrate in the main scanning direction while being carried out repeatedly several times, and further carries out at least one of control for adjusting the driving frequency of a plurality of driving elements in every discharge heads 9 and control for adjusting the relative movement of the work stage 6 and the droplet discharge head 9 so that the number of discharges of the functional liquid discharged to an opening of a partition provided in the substrate from each nozzle of respective droplet discharge head 9 exhibits a proper value. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a droplet discharge device and a droplet discharge method.

  2. Description of the Related Art In recent years, electro-optical devices such as liquid crystal devices and organic EL (Electro-Luminescent) devices have been used for display units of electronic devices such as mobile phones and portable computers. These electro-optical devices generally perform full color display. For example, full color display by a liquid crystal device is displayed by passing light modulated by a liquid crystal layer through a color filter. Such a color filter is formed by ejecting ink on the surface of a substrate in a dot shape by a film forming technique using a droplet discharge method.

  By the way, in the film forming technique using the droplet discharge method, the ink discharge amounts of the plurality of nozzles vary slightly. When drawing with variations in the ink discharge amount, the landing position of the ink on the color filter substrate is shifted, landing on a different color pixel next to it and causing color mixing, or a desired pixel May not be landed and color unevenness may occur. Such pixel color mixture and coloring unevenness are easily visible, and the image quality of the image displayed through the color filter may be degraded.

  A technique for solving such a problem has been examined. For example, in Patent Document 1, among a plurality of droplet discharge heads, nozzles positioned at the extreme ends of adjacent droplet discharge heads are mutually connected. The interval and the sub-scanning pitch of the droplet discharge head are set to an integral multiple of the nozzle arrangement pitch. Further, the droplet discharge head is linearly scanned in the main scanning direction at a constant speed so that the number of ink discharged to the opening of the partition provided on the substrate becomes a predetermined amount. Then, the droplet discharge head is scanned a plurality of times, so that the ink is ejected over the opening of the partition wall a plurality of times. As a result, the landing accuracy of the ink discharged from the droplet discharge head is improved, thereby preventing pixel color mixing and coloring unevenness.

JP 2003-84215 A

In the technique of Patent Document 1, it is considered that the landing accuracy of ink ejected from the droplet ejection head can be improved, and color mixing and coloring unevenness of pixels can be prevented. There is also.
In Patent Document 1, ink is ejected in a plurality of times on the opening of the partition wall at a constant relative speed between the droplet ejection head and the substrate. For example, the ink discharge number (predetermined appropriate value) for one opening is 120 dots, and the maximum ink discharge number per scan is 50 dots. Then, the number of ink ejections per scan (the number of unit ink ejections) is 40 dots, and a predetermined appropriate value (120 dots) is obtained by scanning 3 times as a whole. That is, the unit ink discharge number (40 dots) is obtained by dividing a predetermined appropriate value (120 dots) by a predetermined number of discharges (three times) and averaging within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head is increased, and it takes a long time to scan.

  The present invention has been made in view of such circumstances, and improves the landing accuracy of ink ejected from a droplet ejection head, thereby preventing pixel color mixing and coloring unevenness and obtaining a desired display image. It is an object of the present invention to provide a droplet discharge device and a droplet discharge method that are capable of performing the above-described process and that have excellent production efficiency.

  In order to solve the above problems, a droplet discharge apparatus according to the present invention includes a plurality of nozzles that discharge a functional liquid and a plurality of drive elements that are provided corresponding to the plurality of nozzles. A work stage on which a substrate for landing the functional liquid discharged from the plurality of nozzles is placed, relative movement between each droplet discharge head and the substrate, and discharge operation of each droplet discharge head. Control means for controlling, and the control means performs the relative movement by repeating each droplet discharge head a plurality of times in the main scanning direction intersecting the arrangement direction of the plurality of nozzles with respect to the substrate. When the number of scans at which the number of functional liquid ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate becomes a predetermined appropriate value is N times , (N-1) scans Control for adjusting the driving frequency of the plurality of driving elements for each droplet discharge head, and control for adjusting the relative speed between the work stage on which the substrate is placed and the droplet discharge head, Control for discharging at a first discharge number adjusted by at least one control, and control for adjusting drive frequencies of the plurality of drive elements for each droplet discharge head in one of the N scans And a drive frequency at which at least one control of adjusting the relative speed between the work stage on which the substrate is placed and the droplet discharge head is employed in the (N-1) scans, In this case, the control is performed such that the discharge is performed at a second discharge number different from the first discharge number by making it different from at least one of the relative speeds.

  According to this configuration, since the relative movement between each droplet discharge head and the substrate and the discharge operation of each droplet discharge head are controlled by the control means, the landing accuracy of the ink discharged from the droplet discharge head is improved. Can be made. Further, in the droplet discharge device of the present invention, when the number of scans at which the discharge number of the ink (functional liquid) discharged to the opening becomes a predetermined appropriate value by the control unit is N, (N−1) ) Times of scanning, at least a control for adjusting the driving frequency of a plurality of driving elements for each droplet discharge head and a control for adjusting the relative speed between the work stage on which the substrate is placed and the droplet discharge head are at least Control is performed to discharge at the first discharge number adjusted by one control. Further, in one of the N scans, the second discharge, which is different from the first discharge number, is made different from at least one of the drive frequency and the relative speed adopted in the (N-1) scans. Control is performed to discharge in numbers. As a result, the number of ink ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate is adjusted to a predetermined appropriate value. Therefore, unlike in Patent Document 1, the droplet discharge head is not scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate. That is, the number of unit ink discharges can be set to an arbitrary value without averaging the predetermined appropriate value divided by the predetermined number of discharges within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head can be reduced and the scan time can be eliminated. Therefore, it is possible to improve the landing accuracy of ink ejected from the droplet ejection head, to prevent color mixture and uneven coloring of pixels, and to obtain a desired display image, and to further improve production efficiency. Become.

  Further, in the droplet discharge device, the control unit discharges the nozzles of the droplet discharge heads from the nozzles to the openings at the timing of one of the N scans. Control for relatively increasing the drive frequency of the plurality of drive elements in each droplet discharge head so that the number of functional liquid discharges becomes the predetermined appropriate value, and the work on which the substrate is placed At least one of control for reducing the relative speed between the stage and the droplet discharge head may be performed.

  According to this configuration, the control means controls the relative increase in the driving frequency of the plurality of driving elements for each droplet discharge head at a predetermined scanning timing during a plurality of times of scanning, and the substrate is placed. At least one control of reducing the relative speed between the work stage and the droplet discharge head is performed. As a result, the number of ink ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate is adjusted to a predetermined appropriate value. For example, the predetermined appropriate value is 120 dots, and the maximum ink discharge number (first discharge number) is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to be a predetermined appropriate value (120 dots). On the other hand, in the droplet discharge device of the present invention, the control for relatively increasing the drive frequency of the plurality of drive elements for each droplet discharge head at a predetermined scanning timing during a plurality of scans, and the droplet At least one control of reducing the relative speed between the ejection head and the substrate is performed. For this reason, the number of ink ejections (first ejection number) in the first scan is 50 dots, the number of ink ejections (second ejection number) in the second scan is 70 dots, and the entire scanning is performed twice. It can be controlled to be a predetermined appropriate value (120 dots). Therefore, it is possible to reduce the number of scans of the droplet discharge head, reduce the scan time, and improve the production efficiency.

  Further, in the droplet discharge device, the control unit discharges the nozzles of the droplet discharge heads from the nozzles to the openings at the timing of one of the N scans. Control may be performed to increase the relative speed between the work stage on which the substrate is placed and the droplet discharge head so that the number of functional liquid discharges becomes the predetermined appropriate value.

  According to this configuration, the control unit performs control to increase the relative speed between the work stage on which the substrate is placed and the droplet discharge head at a predetermined scanning timing during scanning a plurality of times. As a result, the number of ink ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate is adjusted to a predetermined appropriate value. For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to be a predetermined appropriate value (120 dots). In contrast, in the droplet discharge device of the present invention, the relative speed between the droplet discharge head and the substrate is increased at a predetermined scanning timing during a plurality of scans. For this reason, the number of ink discharges in the first scan is 50 dots, the number of ink discharges in the second scan is 50 dots, the number of ink discharges in the third scan is 20 dots, and the total number of scans is three. It can be controlled to be a predetermined appropriate value (120 dots). Thus, the scanning speed of the droplet discharge head can be increased so that the number of ink discharges (20 dots) in the third scan is reduced. Therefore, the scanning time of the droplet discharge head is not required, and the production efficiency can be improved.

  The droplet discharge method of the present invention is a droplet discharge method using a droplet discharge head having a plurality of nozzles for discharging a functional liquid and a plurality of drive elements provided corresponding to the plurality of nozzles. Each of the droplet discharge heads is controlled to repeatedly move relative to the substrate a plurality of times in the main scanning direction intersecting the arrangement direction of the plurality of nozzles with respect to the substrate. If the number of scans at which the number of ejections of the functional liquid ejected from the openings to the partition walls provided on the substrate reaches a predetermined appropriate value is N, the number of scans is (N-1) times. At least one of control for adjusting the drive frequency of the plurality of drive elements for each droplet discharge head and control for adjusting the relative speed between the work stage on which the substrate is placed and the droplet discharge head Adjusted by the first A first control step for controlling ejection by the number of ejections, control for adjusting drive frequencies of the plurality of drive elements for each droplet ejection head in one of the N scans, The control of adjusting the relative speed between the mounted work stage and the droplet discharge head, and at least one of the control, the drive frequency adopted in the (N-1) scans, and the relative speed And a second control step of controlling discharge at a second discharge number different from the first discharge number by making it different from at least one.

  According to this manufacturing method, when the number of scans at which the number of ink (functional liquid) ejected to the opening reaches a predetermined appropriate value is N times, the first control step performs (N-1) times. At least a control for adjusting the driving frequency of a plurality of driving elements for each droplet discharge head and a control for adjusting the relative speed between the work stage on which the substrate is placed and the droplet discharge head. Control is performed to discharge at the first discharge number adjusted by one control. Then, one of the N scans is performed by the second control step, and at least one of the drive frequency and the relative speed adopted in the (N-1) scans is made different. Control is performed to discharge at a second discharge number different from the one discharge number. As a result, the number of ink ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate is adjusted to a predetermined appropriate value. Therefore, unlike in Patent Document 1, the droplet discharge head is not scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate. That is, the number of unit ink discharges can be set to an arbitrary value without averaging the predetermined appropriate value divided by the predetermined number of discharges within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head can be reduced and the scan time can be eliminated. Therefore, it is possible to improve the landing accuracy of ink ejected from the droplet ejection head, to prevent color mixture and uneven coloring of pixels, and to obtain a desired display image, and to further improve production efficiency. Become.

  In the droplet discharge method, in the second control step, each droplet discharge head is configured so that the number of the functional liquid discharged to the opening becomes the predetermined appropriate value. At least one of control for relatively increasing the drive frequency of the plurality of drive elements and control for decreasing the relative speed between the work stage on which the substrate is placed and the droplet discharge head. You may go.

  According to this manufacturing method, in the second control step, the control for relatively increasing the drive frequency of the plurality of drive elements for each droplet discharge head and the relative relationship between the work stage on which the substrate is placed and the droplet discharge head are performed. At least one of control for reducing the speed is performed. As a result, the number of ink ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate is adjusted to a predetermined appropriate value. For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to a predetermined appropriate value (120 dots). In contrast, in the droplet discharge method of the present invention, the control for relatively increasing the drive frequency of the plurality of drive elements for each droplet discharge head at a predetermined scanning timing during a plurality of scans, and the droplet At least one of control for reducing the relative speed between the discharge head and the substrate is performed. For this reason, the number of ink ejections in the first scan is 50 dots, the number of ink ejections in the second scan is 70 dots, and the entire value is set to a predetermined appropriate value (120 dots) by performing the scan twice. Can be controlled. Therefore, it is possible to reduce the number of scans of the droplet discharge head, reduce the scan time, and improve the production efficiency.

  Further, in the droplet discharge method, in the second control step, the substrate is placed so that the discharge number of the functional liquid discharged to the opening is the predetermined appropriate value. Control for increasing the relative speed between the work stage and the droplet discharge head may be performed.

  According to this manufacturing method, control for increasing the relative speed between the work stage on which the substrate is placed and the droplet discharge head is performed in the second control step. As a result, the number of ink ejected from each nozzle of each droplet ejection head to the opening of the partition wall provided on the substrate is adjusted to a predetermined appropriate value. For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to a predetermined appropriate value (120 dots). In contrast, in the droplet discharge method of the present invention, control is performed to increase the relative speed between the droplet discharge head and the substrate at a predetermined scanning timing during a plurality of scans. For this reason, the number of ink discharges in the first scan is 50 dots, the number of ink discharges in the second scan is 50 dots, the number of ink discharges in the third scan is 20 dots, and the total number of scans is three. It can be controlled to be a predetermined appropriate value (120 dots). Thus, the scanning speed of the droplet discharge head can be increased so that the number of ink discharges (20 dots) in the third scan is reduced. Therefore, it is possible to reduce the scanning time of the droplet discharge head and improve the production efficiency.

It is a schematic diagram which shows schematic structure of the droplet discharge apparatus which concerns on this invention. It is a schematic diagram which shows schematic structure of a droplet discharge head. It is explanatory drawing of the method of forming a color filter on a color filter board | substrate. It is a figure which shows the process controlled to discharge a predetermined amount of ink with respect to an opening part. It is a figure of the state controlled so that ink was discharged densely with respect to the main scanning direction. It is a figure of the state controlled so that ink was discharged sparsely with respect to the main scanning direction.

  Embodiments of the present invention will be described below with reference to the drawings. This embodiment shows one aspect of the present invention, and does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. Moreover, in the following drawings, in order to make each structure easy to understand, an actual structure and a scale, a number, and the like in each structure are different.

  In the following description, the XYZ rectangular coordinate system shown in FIG. 1 is set, and each member will be described with reference to this XYZ rectangular coordinate system. In the XYZ orthogonal coordinate system, the X axis and the Y axis are set in a direction parallel to the work stage 6, and the Z axis is set in a direction orthogonal to the work stage 6. In the XYZ coordinate system in FIG. 1, the XY plane is actually set to a plane parallel to the horizontal plane, and the Z axis is set to the vertically upward direction.

(Droplet discharge device)
FIG. 1 is a schematic diagram showing a schematic configuration of a droplet discharge device 1 according to the present invention. The droplet discharge device 1 is a device that forms a color filter layer by discharging droplets of a color filter material (functional liquid) onto a predetermined region of a color filter substrate (substrate) P by, for example, an inkjet method.

  The droplet discharge device 1 includes a base 2 on which the color filter substrate P is placed, a transport device 3 that transports the color filter substrate P on the base 2 in the X direction in FIG. 1, and droplets that discharge ink. A discharge head 9, a carriage 4 including a plurality of droplet discharge heads 9, a feed device 5 that moves the carriage 4 in the Y direction, a work stage 6 that constitutes the transfer device 3, and a droplet discharge head 9 And a control device 8 (control means) for controlling the relative movement and controlling the ejection operation of each droplet ejection head 9. The transport device 3 and the feeding device 5 constitute a moving device that relatively moves the substrate P and the carriage 4 in the X direction and the Y direction, respectively.

  The transfer device 3 includes a work stage 6 and a stage moving device 7 provided on the base 2. The work stage 6 is provided so as to be movable in the X direction on the base 2 by a stage moving device 7, and a color filter substrate P transported from an upstream transport device (not shown) is vacuum-sucked, for example. It is held on the XY plane by a mechanism. The stage moving device 7 includes a bearing mechanism such as a ball screw or a linear guide. The stage moving device 7 moves the work stage 6 in the X direction based on a stage position control signal indicating the X coordinate of the work stage 6 input from the control device 8. It is comprised so that it may move to.

  The carriage 4 is a rectangular plate that is movably attached to the feeding device 5, and holds a plurality of droplet discharge heads 9 arranged on the bottom surface side along the Y direction. The plurality of liquid droplet ejection heads 9 are provided with a plurality of nozzles N as will be described later, and eject ink droplets based on drawing data and drive control signals input from the control device 8. is there. These droplet discharge heads 9 are provided corresponding to the color filter materials R (red), G (green), and B (blue). As shown, a tube (piping) 10 is connected via a carriage 4.

  The droplet discharge head 9R corresponding to R (red) is connected to a first tank 11R filled and stored with ink for R (red) via the tube 10, thereby the droplet discharge head. 9R is supplied with R (red) ink from the first tank 11R. Similarly, a second tank 11G filled with ink for G (green) is connected to the droplet discharge head 9G corresponding to G (green), and B is connected to the droplet discharge head 9B corresponding to B (blue). A third tank 11B filled with (blue) ink is connected. With this configuration, G (green) ink is supplied from the second tank 11G to the droplet discharge head 9G, and the third tank 11B to B (B ( Blue) ink is supplied.

  FIG. 2 is a diagram showing a schematic configuration of a droplet discharge head 9 having a piezoelectric element PZ constituting the droplet discharge apparatus 1 of the present invention. 2A is a plan view of a droplet discharge head 9 that discharges droplets of, for example, a color filter forming material, as viewed from the side where droplets are discharged onto the color filter substrate P, and FIG. FIG. 2C is a partial cross-sectional view of one nozzle of the droplet discharge head 9.

As shown in FIG. 2A, the droplet discharge head 9 includes a plurality of (for example, 180) nozzles N _{1 to} N ₁₈₀ arranged in the Y-axis direction. A nozzle row NA is formed by the nozzles N _{1 to} N ₁₈₀ . Although FIG. 2A shows one row of nozzles, the number of nozzles and the number of nozzle rows provided in the droplet discharge head 9 can be arbitrarily changed, and one row of nozzles arranged in the Y-axis direction. A plurality of rows may be provided in the X-axis direction.

As shown in FIG. 2B, the droplet discharge head 9 is provided with a diaphragm 20 provided with a material supply hole 20a connected to a tube 10 for supplying a material, and nozzles N _{1 to} N ₁₈₀ . A nozzle plate 21, a liquid reservoir 22 provided between the vibration plate 20 and the nozzle plate 21, a plurality of partition walls 23, and a plurality of storage chambers 24 are provided. On the vibration plate 20, piezoelectric elements PZ _{1 to} PZ ₁₈₀ are arranged corresponding to the nozzles N1 to N180. The drive elements PZ _{1 to} PZ ₁₈₀ are, for example, piezo elements.

The liquid reservoir 22 is filled with a liquid color filter material supplied through the material supply hole 20a. The storage chamber 24 is formed so as to be surrounded by the vibration plate 20, the nozzle plate 21, and a pair of partition walls 23. The storage chamber 24 is provided in a one-to-one correspondence with each of the nozzles N _{1 to} N ₁₈₀ . Further, the color filter material is introduced into each storage chamber 24 from the liquid reservoir 22 through a supply port 24 a provided between the pair of partition walls 23.

  As shown in FIG. 2C, the piezoelectric element PZ has a piezoelectric material 25 sandwiched between a pair of electrodes 26. The piezoelectric element PZ is configured such that the piezoelectric material 25 contracts when a drive signal is applied to the pair of electrodes 26. The diaphragm 20 in which such a piezoelectric element PZ is disposed is bent integrally with the piezoelectric element PZ and simultaneously outward (opposite the storage chamber 24) when a drive signal is applied to the pair of electrodes 26. As a result, the volume of the storage chamber 24 is increased.

  When the volume of the storage chamber 24 increases, the color filter material corresponding to the increased volume in the storage chamber 24 flows from the liquid reservoir 22 through the supply port 24a. Further, when the application of the drive signal to the piezoelectric element PZ is stopped from such a state, both the piezoelectric element PZ and the diaphragm 20 return to the original shape, and the storage chamber 24 also returns to the original volume. As a result, the pressure of the color filter material in the storage chamber 24 increases, and droplets L of the color filter material are discharged from the nozzle N toward the color filter substrate P.

  The feed device 5 for moving the carriage 4 has, for example, a bridge structure straddling the base 2 and includes a bearing mechanism such as a ball screw or a linear guide in the Y direction and the Z direction orthogonal to the XY plane. is there. Based on such a configuration, the feeding device 5 moves the carriage 4 in the Y direction based on the carriage position control signal indicating the Y coordinate and Z coordinate of the carriage 4 input from the control device 8, and It is also designed to move in the direction.

  The control device 8 outputs a stage position control signal to the stage moving device 7, outputs a carriage position control signal to the feeding device 5, and further draws drawing data and data on a drive circuit board (not shown) of the droplet discharge head 9. A drive control signal is output. Thus, the control device 8 performs the positioning operation of the color filter substrate P by the movement of the work stage 6 and the positioning operation of the droplet discharge head 9 by the movement of the carriage 4 in order to move the color filter substrate P and the carriage 4 relative to each other. By performing synchronous control and causing the droplet discharge head 9 to perform a droplet discharge operation, ink droplets are arranged at a predetermined position on the color filter substrate P at a predetermined timing. In this way, the relative movement between each droplet discharge head 9 and the color filter substrate P and the discharge operation of each droplet discharge head 9 are controlled by the control device 8, so that the ink discharged from the droplet discharge head 9 is The landing accuracy can be improved.

  In the present embodiment, when the number of scans at which the number of ink ejected to the opening 31 of the partition wall 30 shown in FIG. 4 by the control device 8 is a predetermined appropriate value is N, (N−1) In each scan, control for adjusting the drive frequency of the plurality of drive elements PZ for each droplet discharge head 9 and the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 are adjusted. And control to discharge at the first discharge number (maximum discharge number) adjusted by at least one of the control to perform the control. Further, in one of the N scans, the second discharge, which is different from the first discharge number, is made different from at least one of the drive frequency and the relative speed adopted in the (N-1) scans. Control is performed to discharge in numbers. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 provided in the color filter substrate P is adjusted to a predetermined appropriate value described later. Therefore, unlike in Patent Document 1, the droplet discharge head is not scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate. That is, the number of unit ink discharges can be set to an arbitrary value without averaging the predetermined appropriate value divided by the predetermined number of discharges within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head 9 can be reduced and the scan time can be eliminated.

  FIG. 3 is an explanatory diagram of a method for forming a color filter layer (color filter) CF on the color filter substrate P using a plurality of droplet discharge heads 9. FIG. 3A is a schematic plan view of a color filter substrate P that is an ink discharge target. FIG. 3B is a partially enlarged plan view of the color filter substrate P. In the drawing, for convenience, one droplet discharge head 9 of the plurality of droplet discharge heads 9 is illustrated.

  In FIG. 3A, a plurality of panel areas CA are set on the surface of a large-area color filter substrate P formed of glass, plastic or the like. Each panel area CA is separated (cut) from each other and provided as an individual color filter substrate. In each panel area CA, as shown in FIG. 3B, a plurality of pixels PX (predetermined areas) arranged in a dot shape are provided. The pixels PX are arranged in a matrix in each panel area CA, and a color filter layer (colored layer) CF is formed for each pixel PX.

  3B is the main scanning direction, and the direction perpendicular to the main scanning direction (the horizontal direction in the drawing) is the sub-scanning direction. It is arranged on the color filter substrate P. The color filter substrate P includes a coloring material from the plurality of nozzles N of each droplet discharge head 9 while moving (scanning) the color filter substrate P relative to each droplet discharge head 9 in the main scanning direction and the sub-scanning direction. Ink (color filter material) is ejected, and a color filter layer CF is formed on each pixel PX on the color filter substrate P.

  Each droplet discharge head 9 is scanned a plurality of times for one panel area CA. For example, after each droplet discharge head 9 is scanned in the main scanning direction, each droplet discharge head 9 is moved (scanned) in the sub-scanning direction, and scanning is performed again in the main scanning direction. After moving (sub-scanning) from the left end to the right end of one panel area CA, it returns to the left end of the panel area CA again, and scans in the main scanning direction at a position slightly different from the position where the ejection has already been performed. Then, by performing such scanning a plurality of times, the color filter layer CF having a desired film thickness is formed on all the pixels PX in the panel area CA.

  In FIG. 3B, each droplet discharge head 9 is inclined with respect to the sub-scanning direction in order to match the pitch of the nozzles N of each droplet discharge head 9 with the pitch of the pixels PX. . If the pitch of the nozzles N and the pitch of the pixels PX are set so as to satisfy a predetermined correspondence relationship, it is not necessary to tilt the droplet discharge head 9 obliquely.

  The color filter layer CF is formed by arranging R, G, and B colors in an appropriate arrangement form such as a so-called stripe arrangement, delta arrangement, mosaic arrangement, or the like. Therefore, in the ink ejection process shown in FIG. 3B, a plurality of droplet ejection heads 9 for ejecting R, G, and B color filter materials are prepared in advance for the three colors R, G, and B. . Then, an array of three color filter layers CF of R, G, and B is formed on one color filter substrate P by sequentially using the plurality of droplet discharge heads 9.

  When such a color filter layer CF is used as an optical element for full-color display, the color filter layers CF of three colors R, G, and B are used as one unit, and R, G, and B in one unit are used. Full color display is performed by selectively transmitting light through any one or a combination thereof. At this time, the partition walls 30 formed of a resin material having no light shielding function function as a black matrix.

  By the way, generally in a droplet discharge head, the ink discharge amount of a plurality of nozzles varies slightly. When drawing with variations in the ink discharge amount, the landing position of the ink on the color filter substrate is shifted, landing on a different color pixel next to it and causing color mixing, or a desired pixel May not be landed and color unevenness may occur. Such pixel color mixture and coloring unevenness are easily visible and cause a reduction in image quality of an image displayed through the color filter.

  In order to solve such a problem, for example, in Patent Document 1, ink is ejected in a plurality of times by overlapping the opening of the partition wall provided on the substrate at a constant relative speed between the droplet ejection head and the substrate. ing. For example, the ink discharge number (predetermined appropriate value) for one opening is 120 dots, and the maximum ink discharge number per scan is 50 dots. Then, the number of ink ejections per scan (the number of unit ink ejections) is 40 dots, and a predetermined appropriate value (120 dots) is obtained by scanning 3 times as a whole. That is, the unit ink discharge number (40 dots) is obtained by dividing a predetermined appropriate value (120 dots) by a predetermined number of discharges (three times) and averaging within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head is increased, and it takes a long time to scan.

  Therefore, in the droplet discharge method of the present invention, the opening 31 of the partition wall 30 provided on the color filter substrate P placed on the work stage 6 from each nozzle N of each droplet discharge head 9 (see FIG. 4). (N-1) scans are performed so that a predetermined amount of ink is ejected with respect to the ink, and control for adjusting the drive frequency of the plurality of drive elements PZ in each droplet discharge head 9 is performed. There is provided a first control step for performing control for discharging at a first discharge number adjusted by at least one of the control for adjusting the relative speed with the droplet discharge head 9. Also, one of the N scans is performed so that the number of ink ejected to the opening 31 of the partition wall 30 is a predetermined appropriate value, and in the (N−1) scans. A second control step is provided in which at least one of the employed drive frequency and the relative speed is made different so as to control ejection at a second ejection number different from the first ejection number. Hereinafter, an example of the droplet discharge method of the present invention will be described.

(Droplet ejection method)
4 to 6 are schematic views showing a droplet discharge method according to the present invention. FIG. 4 shows a first control process for performing control so that a predetermined amount of ink is ejected to the opening 31 of the partition wall 30 provided on the color filter substrate P. 5 and 6 show a second control process in which control is performed so that the number of ink ejected to the opening 31 of the partition wall 30 becomes a predetermined appropriate value. One of these drawings is a state in which control is performed to reduce the relative speed between the work stage 6 and the droplet discharge head 9, that is, control is performed so that ink is discharged densely in the main scanning direction. It shows the state that was done. FIG. 6 on the other side shows a state in which the relative speed between the work stage 6 and the droplet discharge head 9 is increased, and a state in which the ink is controlled to be discharged sparsely in the main scanning direction. Show.

  As shown in FIGS. 4 to 6, in the partition wall 30 provided on the color filter substrate P, a plurality of openings 31 are formed in a matrix at positions corresponding to the pixels PX. The interval between the inks ejected into the plurality of openings 31 (the distance between the centers of adjacent inks) is a constant interval corresponding to the pitch PN of the plurality of nozzles N of the droplet ejection head 9. Yes.

  First, as shown in FIG. 4, relative movement between the work stage 6 and the droplet discharge head 9 is controlled in a plurality of openings 31 to discharge a predetermined amount of ink. Specifically, the color filter substrate P is moved from the plurality of nozzles N of each droplet discharge head 9 while being moved (scanned) relative to each droplet discharge head 9 in the main scanning direction and the sub-scanning direction. A fixed amount of ink is ejected. For example, the ink discharge number (predetermined appropriate value) for one opening 31 is 120 dots, and the maximum ink discharge number per scan is 50 dots. In the first control step (first scan), the predetermined number of ink ejections (first ejection number) ejected to the openings 31 is 50 dots, which is the same as the maximum ink ejection number.

  Then, as shown in FIG. 5, the control device 8 performs control to reduce the relative speed between the work stage 6 and the droplet discharge head 9, and ink is discharged so that a predetermined appropriate value (120 dots) is obtained. Is done. Specifically, the control device 8 ejects ink densely in the main scanning direction so that the number of ink ejected to the opening 31 is a predetermined appropriate value (120 dots). . In the second control step (second scan), the number of ink ejected to the opening 31 (second ejection number) is a predetermined amount of ink ejected in the first scan (120 dots) from the predetermined appropriate value (120 dots). 50 dots) is subtracted from the ink discharge number, which is 70 dots.

  In this manner, the relative speed between the droplet discharge head 9 and the color filter substrate P is reduced at the second scanning, that is, the last scanning timing (final scanning) during a plurality of times of scanning, and the ink is moved in the main scanning direction. Are discharged densely. For this reason, for example, the number of ink ejections in the first scanning (first ejection number) is 50 dots, the number of ink ejections in the second scanning (second ejection number) is 70 dots, and the scanning is performed twice as a whole. Can be controlled to a predetermined appropriate value (120 dots). Therefore, the number of scans of the droplet discharge head 9 can be reduced and the scan time can be eliminated.

  According to the droplet discharge device 1 of the present embodiment, the relative movement between each droplet discharge head 9 and the color filter substrate P and the discharge operation of each droplet discharge head 9 are controlled by the control device 8. The landing accuracy of the ink ejected from the droplet ejection head 9 can be improved. Further, in the liquid droplet ejection apparatus 1 of the present invention, when the number of scans at which the ejection number of the ink ejected to the opening 31 becomes a predetermined appropriate value by the control device 8 is N, (N−1) In each scan, control for adjusting the drive frequency of the plurality of drive elements PZ for each droplet discharge head 9 and the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 are adjusted. And control to discharge at the first discharge number adjusted by at least one of the control to perform the control. Further, in one of the N scans, the second discharge, which is different from the first discharge number, is made different from at least one of the drive frequency and the relative speed adopted in the (N-1) scans. Control is performed to discharge in numbers. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 of the partition wall 30 provided on the color filter substrate P is adjusted to be a predetermined appropriate value. . Therefore, unlike in Patent Document 1, the droplet discharge head 9 is not scanned a plurality of times at a constant relative speed between the droplet discharge head 9 and the color filter substrate P. That is, the number of unit ink discharges can be set to an arbitrary value without averaging the predetermined appropriate value divided by the predetermined number of discharges within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head 9 can be reduced and the scan time can be eliminated. Therefore, it is possible to improve the landing accuracy of the ink ejected from the droplet ejection head 9, to prevent pixel color mixing and coloring unevenness, and to obtain a desired display image, and to further improve the production efficiency. It becomes.

  According to this configuration, the control device 8 can control to reduce the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 at a predetermined scanning timing during a plurality of times of scanning. Done. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 of the partition wall 30 provided on the color filter substrate P is adjusted to be a predetermined appropriate value. . For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to a predetermined appropriate value (120 dots). In contrast, in the droplet discharge device 1 of the present invention, the relative speed between the droplet discharge head 9 and the color filter substrate P is reduced at a predetermined scanning timing during a plurality of scans. For this reason, for example, the number of ink ejections in the first scan is 50 dots, the number of ink ejections in the second scan is 70 dots, and the overall value is set to a predetermined appropriate value (120 dots) by performing the scan twice. Can be controlled. Therefore, it is possible to reduce the number of scans of the droplet discharge head 9 and reduce the scan time, thereby improving the production efficiency.

  In the droplet discharge device 1 according to the present embodiment, the control device 8 causes the work stage 6 and the droplet discharge head 9 on which the color filter substrate P is placed at a predetermined scanning timing during scanning a plurality of times. Although the control to reduce the relative speed is performed, it is not limited to this. For example, the control device 8 may perform control to relatively increase the driving frequency of the plurality of driving elements PZ for each droplet discharge head 9 at a predetermined scanning timing during scanning a plurality of times. That is, the control device 8 controls to reduce the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 at a predetermined scanning timing during a plurality of scans, and droplet discharge. It is sufficient that at least one of the control for relatively increasing the drive frequency of the plurality of drive elements PZ for each head 9 is performed.

  According to the droplet discharge method of the present embodiment, (N-1) scans are performed in the first control step, and the control for adjusting the drive frequency of the plurality of drive elements PZ in each droplet discharge head 9 is performed. Then, control is performed to discharge at the first discharge number adjusted by at least one of the control for adjusting the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9. Then, one of the N scans is performed by the second control step, and at least one of the drive frequency and the relative speed adopted in the (N-1) scans is made different. Control is performed to discharge at a second discharge number different from the one discharge number. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 of the partition wall 30 provided on the color filter substrate P is adjusted to be a predetermined appropriate value. . Therefore, unlike in Patent Document 1, the droplet discharge head is not scanned a plurality of times at a constant relative speed between the droplet discharge head 9 and the color filter substrate P. That is, the number of unit ink discharges can be set to an arbitrary value without averaging the predetermined appropriate value divided by the predetermined number of discharges within the range of the maximum ink discharge number. For this reason, the number of scans of the droplet discharge head 9 can be reduced and the scan time can be eliminated. Therefore, it is possible to improve the landing accuracy of the ink ejected from the droplet ejection head 9, to prevent pixel color mixing and coloring unevenness, and to obtain a desired display image, and to further improve the production efficiency. It becomes.

  Further, according to this manufacturing method, control is performed to reduce the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 in the second control step. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 of the partition wall 30 provided on the color filter substrate P is adjusted to be a predetermined appropriate value. . For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to a predetermined appropriate value (120 dots). In contrast, in the droplet discharge method of the present invention, control is performed to reduce the relative speed between the droplet discharge head 9 and the color filter substrate P at a predetermined scanning timing during a plurality of scans. For this reason, the number of ink ejections in the first scan is 50 dots, the number of ink ejections in the second scan is 70 dots, and the entire value is set to a predetermined appropriate value (120 dots) by performing the scan twice. Can be controlled. Therefore, it is possible to reduce the number of scans of the droplet discharge head 9 and reduce the scan time, thereby improving the production efficiency.

  In the droplet discharge method, the control for reducing the relative speed between the droplet discharge head 9 and the color filter substrate P is performed in the final scan in the second control step, but the present invention is not limited to this. For example, it may be performed at a predetermined scanning timing during a plurality of times of scanning in the first control step. That is, it is only necessary to perform control to reduce the relative speed between the droplet discharge head 9 and the color filter substrate P so that the number of ink discharged to the opening 31 becomes a predetermined appropriate value.

  In the droplet discharge method, the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 is determined at a predetermined scanning timing during a plurality of scans in the second control step. However, the present invention is not limited to this. For example, control for relatively increasing the drive frequency of the plurality of drive elements PZ in each droplet discharge head 9 may be performed. That is, in the second control step, the control is performed to reduce the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 at a predetermined scanning timing during a plurality of times of scanning. It is only necessary to perform at least one control of relatively increasing the drive frequency of the plurality of drive elements PZ for each ejection head 9.

  On the other hand, as shown in FIG. 6, the control device 8 performs control to increase the relative speed between the work stage 6 and the droplet discharge head 9, and ink is discharged so as to have a predetermined appropriate value (120 dots). May be. Specifically, the control device 8 ejects ink sparsely in the main scanning direction so that the number of ink ejected to the opening 31 is a predetermined appropriate value (120 dots).

  Specifically, in the second control step, a total of two scans, the second scan and the third scan, are performed. The number of ink ejected to the opening 31 in the second scan is 50 dots, the same as the predetermined number of ink ejects (50 dots) in the first scan. The number of ink ejections (second ejection number) ejected to the opening 31 in the third scanning is the predetermined number of ink ejections (50 dots) in the first scanning from the predetermined appropriate value (120 dots). The total number of ink ejections (100 dots) obtained by subtracting the predetermined number of ink ejections (50 dots) in the second scan is 20 dots.

  In this manner, the relative speed between the droplet discharge head 9 and the color filter substrate P is increased in the third scan, that is, the final scan. For this reason, for example, the number of ink ejections in the first scan (first ejection number) is 50 dots, the number of ink ejections in the second scanning (first ejection number) is 50 dots, and the number of ink ejections in the third scanning (first number). (2 ejection number) is set to 20 dots, and it can be controlled to be a predetermined appropriate value (120 dots) by scanning three times as a whole. At this time, the scanning speed of the droplet discharge head 9 can be increased so that the number of ink discharges (20 dots) is reduced in the third scan. Therefore, the scanning time of the droplet discharge head 9 can be eliminated.

  According to this configuration, the control device 8 performs control to increase the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 at a predetermined scanning timing during a plurality of times of scanning. Done. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 of the partition wall 30 provided on the color filter substrate P is adjusted to be a predetermined appropriate value. . For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to a predetermined appropriate value (120 dots). On the other hand, in the droplet discharge device 1 of the present invention, control is performed to increase the relative speed between the color filter of the droplet discharge head 9 and the substrate P at a predetermined scanning timing during a plurality of scans. For this reason, the number of ink discharges in the first scan is 50 dots, the number of ink discharges in the second scan is 50 dots, the number of ink discharges in the third scan is 20 dots, and the total number of scans is three. It can be controlled to be a predetermined appropriate value (120 dots). Thus, the scanning speed of the droplet discharge head 9 can be increased so that the number of ink discharges (20 dots) in the third scan is reduced. Accordingly, the scanning time of the droplet discharge head 9 is not required, and the production efficiency can be improved.

  According to this manufacturing method, control for increasing the relative speed between the work stage 6 on which the color filter substrate P is placed and the droplet discharge head 9 is performed in the second control step. As a result, the number of ink ejected from each nozzle N of each droplet ejection head 9 to the opening 31 of the partition wall 30 provided on the color filter substrate P is adjusted to be a predetermined appropriate value. . For example, the predetermined appropriate value is 120 dots, and the maximum ink ejection number is 50 dots. In the prior art example, the droplet discharge head is scanned a plurality of times at a constant relative speed between the droplet discharge head and the substrate, the number of unit ink discharges is 40 dots, and the scan is performed three times as a whole. Is controlled to a predetermined appropriate value (120 dots). In contrast, in the droplet discharge method of the present invention, control is performed to increase the relative speed between the droplet discharge head 9 and the color filter substrate P at a predetermined scanning timing during a plurality of scans. For this reason, the number of ink discharges in the first scan is 50 dots, the number of ink discharges in the second scan is 50 dots, the number of ink discharges in the third scan is 20 dots, and the total number of scans is three. It can be controlled to be a predetermined appropriate value (120 dots). Thus, the scanning speed of the droplet discharge head 9 can be increased so that the number of ink discharges (20 dots) in the third scan is reduced. Accordingly, the scanning time of the droplet discharge head 9 is not required, and the production efficiency can be improved.

  In the droplet discharge method, the control for increasing the relative speed between the droplet discharge head 9 and the color filter substrate P is performed in the final scan in the second control step, but the present invention is not limited to this. For example, it may be performed at a predetermined scanning timing during a plurality of times of scanning in the first control step. That is, it is only necessary to perform control to increase the relative speed between the droplet discharge head 9 and the color filter substrate P so that the number of ink discharged to the opening 31 becomes a predetermined appropriate value.

DESCRIPTION OF SYMBOLS 1 ... Droplet discharge device, 6 ... Work stage, 8 ... Control apparatus (control means), 9, 9R, 9G, 9B ... Droplet discharge head, 30 ... Partition, 31 ... Opening, N ... Nozzle, P ... Color Filter substrate (substrate), PZ ... Drive element

Claims (6)

A droplet discharge head having a plurality of nozzles for discharging a functional liquid, and a plurality of drive elements provided corresponding to the plurality of nozzles;
A work stage on which a substrate for landing the functional liquid discharged from the plurality of nozzles is placed;
Control means for controlling the relative movement between each droplet discharge head and the substrate and the discharge operation of each droplet discharge head;
The control means performs control to repeatedly move the droplet discharge heads relative to the substrate a plurality of times in a main scanning direction intersecting the arrangement direction of the plurality of nozzles. When the number of scans at which the discharge number of the functional liquid discharged from the nozzles to the opening of the partition wall provided on the substrate is a predetermined appropriate value is N times,
In (N-1) times of scanning, control for adjusting the driving frequency of the plurality of driving elements for each of the droplet discharge heads, and the relative relationship between the work stage on which the substrate is placed and the droplet discharge heads Control to adjust the speed and control to discharge at a first discharge number adjusted by at least one of the controls,
In one of the N scans, control for adjusting the drive frequency of the plurality of drive elements for each droplet discharge head, the work stage on which the substrate is placed, the droplet discharge head, By controlling at least one of the control for adjusting the relative speed of at least one of the drive frequency employed in the (N-1) scans and at least one of the relative speed, the first ejection number A droplet discharge device that performs discharge control with a different second discharge number.   The control means is configured so that the number of functional liquid ejected from the nozzles of the droplet ejection heads to the opening at the timing of one of the N scans is the predetermined appropriate value. A control for relatively increasing the drive frequency of the plurality of drive elements for each of the droplet discharge heads, and a relative relationship between the work stage on which the substrate is placed and the droplet discharge head. The droplet discharge device according to claim 1, wherein at least one of control for reducing the speed is performed.   The control means is configured so that the number of functional liquid ejected from the nozzles of the droplet ejection heads to the opening at the timing of one of the N scans is the predetermined appropriate value. 2. The droplet discharge apparatus according to claim 1, wherein control is performed to increase a relative speed between the work stage on which the substrate is placed and the droplet discharge head so as to be a value. A droplet discharge method using a droplet discharge head having a plurality of nozzles for discharging a functional liquid and a plurality of drive elements provided corresponding to the plurality of nozzles,
The droplet discharge head is controlled to repeatedly move relative to the substrate a plurality of times in the main scanning direction intersecting the arrangement direction of the plurality of nozzles, and the substrate of each droplet discharge head is moved from the nozzle to the substrate. When the number of scans at which the ejection number of the functional liquid ejected to the opening of the partition wall provided in is a predetermined appropriate value is N times,
Control for adjusting the driving frequency of the plurality of driving elements for each of the droplet discharge heads in (N-1) scans, and the relative relationship between the work stage on which the substrate is placed and the droplet discharge head A first control step of performing control to discharge at a first number of discharges adjusted by at least one of the control to adjust the speed;
Control for adjusting the drive frequency of the plurality of drive elements for each of the droplet discharge heads in one of the N scans, the work stage on which the substrate is placed, the droplet discharge head, By controlling at least one of the control for adjusting the relative speed of at least one of the drive frequency employed in the (N-1) scans and at least one of the relative speed, the first ejection number A second control step for controlling discharge at a different second discharge number;
A droplet discharge method comprising:   In the second control step, the drive frequency of the plurality of drive elements for each of the droplet discharge heads is set so that the number of the functional liquid discharged to the opening becomes the predetermined appropriate value. 5. The control according to claim 4, wherein at least one of control for relatively increasing and control for decreasing a relative speed between the work stage on which the substrate is placed and the droplet discharge head is performed. The droplet discharge method described.   In the second control step, the work stage on which the substrate is placed, the droplet discharge head, and the like so that the discharge number of the functional liquid discharged to the opening becomes the predetermined appropriate value. The droplet discharge method according to claim 4, wherein control is performed to increase the relative speed of the droplets.

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