JP2012106148A - Droplet coating device and droplet coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the case that a worker performs maintenance work for returning improper nozzles to proper states even if there are the improper nozzles in a coating head, and to suppress the lowering of an operating ratio.SOLUTION: This droplet coating device relatively scan-moves a coating head in which a plurality of the nozzles are aligned in a prescribed direction and a base board having a coating region in a direction which intersects with the aligning direction of the nozzles, and coats the droplets of a coating liquid on the coating region by discharging the droplets from the nozzles which oppose the coating region at the scan-movement. The droplet coating device includes a detection part which detects discharge states of the droplets from the nozzles, a movement drive part which relatively moves the coating head and the base board in the alignment direction of the nozzles, and a control part 25 which controls the detection part and the movement drive part. The control part 25 determines whether or not the discharge state of the droplet from each nozzle is proper on the basis of the detection result of the detection part 23, and when there are the improper nozzles, controls the movement drive part 10 so that the improper nozzles are positioned out of the coating region.

Description

  The present invention relates to a droplet coating apparatus and a droplet coating method for discharging droplets from a nozzle of a coating head and coating a coating target.

  The droplet applying device is used for manufacturing a display device such as a liquid crystal display device or an organic EL (Electro Luminescence) display device or a semiconductor device, for example, when forming a color filter, or a substrate such as a glass substrate or a semiconductor wafer. It is used when forming a functional thin film such as an alignment film or a resist.

  This droplet coating apparatus includes a coating head that discharges a coating liquid such as ink from a plurality of nozzles toward a coating target such as a substrate. The droplet coating device forms a predetermined thin film by ejecting the coating liquid as droplets from the nozzle while relatively moving the coating head and the coating target, and applying the droplets to the coating area of the coating target. ing.

  In such a droplet coating apparatus, there are cases where a nozzle (hereinafter referred to as “inappropriate nozzle”) having an inappropriate droplet discharge state occurs due to various causes. For example, non-ejection of droplets from the nozzle caused by air bubbles mixed in the coating liquid, or liquid from the nozzle caused by foreign matter entering the nozzle when the nozzle surface of the coating head is wiped and clogging the nozzle For example, non-ejection of droplets.

  When an improper nozzle is generated, the amount of coating solution applied to each coating region varies, resulting in variations in the thickness of the thin film formed by the applied coating solution, resulting in a decrease in the yield of the finished product. .

  Therefore, when an improper nozzle is generated, for example, when non-ejection of a droplet from the nozzle due to air bubbles being mixed in the coating liquid, as described in Patent Document 1 below, Maintenance work is performed to remove bubbles from the nozzle, and the discharge state of droplets from the nozzle is returned to an appropriate state.

JP 2003-275659 A

  However, in order to perform a maintenance operation for returning the droplet discharge state from the improper nozzle to an appropriate state when an improper nozzle occurs, it is necessary to interrupt the droplet application operation by the droplet applying apparatus. . For this reason, every time an inappropriate nozzle is generated, a maintenance operation for returning the droplet discharge state from the inappropriate nozzle to an appropriate state causes a problem that the operating rate of the droplet applying apparatus is remarkably lowered.

  The present invention has been made in view of the above, and its purpose is to reduce the chance of performing maintenance work for returning the improper nozzle to an appropriate state even when an improper nozzle is generated in the coating head, and the operation rate It is an object to provide a droplet coating apparatus and a droplet coating method that can suppress a decrease in the above.

A first feature according to the embodiment of the present invention is that an arrangement direction of the nozzles includes a coating head in which a plurality of nozzles for discharging droplets of a coating liquid are arranged in a predetermined direction and a substrate having a coating region. In the liquid droplet applying apparatus for applying a liquid droplet of the coating liquid to the coating area by discharging the liquid droplets from the nozzle facing the coating area during the scanning movement. A detection unit that detects a discharge state of droplets from the nozzles, a movement drive unit that relatively moves the coating head and the substrate in the arrangement direction of the nozzles, and the movement based on a detection result of the detection unit A control unit that controls the drive unit, and the control unit determines whether or not the discharge state of the droplet from each nozzle is appropriate based on the detection result of the detection unit, and the discharge state of the droplet is not appropriate Judged that there is an inappropriate nozzle The time was the time of the scanning movement for applying the droplets to the coating region, is to control the movement driving portion such that the non-proper nozzle is located off from said coating region.

  A second feature of the embodiment of the present invention is that an arrangement direction of the nozzles includes a coating head in which a plurality of nozzles for discharging droplets of a coating liquid are arranged in a predetermined direction and a substrate having a coating region. In the liquid droplet coating method, the liquid droplets are ejected from the nozzles facing the coating area during the scanning movement, and the droplets of the coating liquid are coated on the coating area. Detecting the discharge state of the liquid droplets discharged from the nozzles, determining whether the discharge state of the liquid droplets discharged from the individual nozzles is appropriate, and the discharge state of the liquid droplets are not appropriate. When there is an improper nozzle, the application head and the substrate are placed so that the improper nozzle is positioned away from the application region during the scanning movement for applying droplets to the application region. Nozzle arrangement direction A step of relatively moving, is to comprise a.

  According to the present invention, even when an improper nozzle having an inappropriate droplet discharge state occurs, the chance of performing maintenance work for returning the improper nozzle to an appropriate state can be reduced. It is possible to prevent a decrease in operating rate.

It is a front view which shows the solution coating apparatus which concerns on the 1st Embodiment of this invention. It is a top view which shows a solution coating device. It is a side view which shows a solution coating device. It is sectional drawing which shows a coating head. It is a block diagram which shows the function of a control part. It is a schematic diagram explaining the movement of the coating head when an improper nozzle is generated. It is a flowchart explaining the process of setting the position of a nozzle. It is a block diagram explaining the function of the control part in the solution coating apparatus which concerns on the 2nd Embodiment of this invention. It is a mimetic diagram explaining processing when an improper nozzle occurs. It is a flowchart explaining the process of setting the position of a nozzle. It is a block diagram explaining the function of the control part in the droplet application apparatus which concerns on the 3rd Embodiment of this invention. It is a mimetic diagram explaining processing when an improper nozzle occurs. It is a flowchart explaining the process of setting the position of a nozzle.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 to 3, the droplet applying apparatus 1 according to the first embodiment of the present invention has a base 2 arranged in a horizontal state, and the width direction of the upper surface of the base 2 (arrow Y) A pair of guide members 3 provided along the longitudinal direction (arrow X direction) of the upper surface of the base 2 are fixed to both sides of the direction. A mounting table 4 is supported on the upper surfaces of both guide members 3 by slidably engaging receiving members 5 provided on both sides of the lower surface in the width direction (arrow Y direction).

  The guide member 3 is provided with a stator (not shown), the receiving member 5 is provided with a mover (not shown), and the mounting table 4 is attached to the guide member 3 by these stator and mover. A linear motor (not shown) is configured to move in the direction of arrow X along.

  On the mounting table 4, a substrate 6 that is an object to be coated, for example, a glass substrate 6 used in a liquid crystal display device is mounted. The substrate 6 is sucked and held on the mounting table 4 by means such as vacuum suction or electrostatic suction. Therefore, the substrate 6 placed on the placement table 4 is scanned and moved in the direction of the arrow X along the guide member 3 together with the placement table 4.

  A gate-shaped support body 7 straddling a pair of guide members 3 is erected in the middle part of the base 2 in the longitudinal direction. A pair of mounting plates 8 are fixed to be opposed to each other on the support 7, and between these mounting plates 8, there are a ball screw 9 and a drive motor 10 that is a moving drive unit that rotationally drives the ball screw 9. Is provided. The ball screw 9 is arranged with an axial center in a direction (arrow Y direction) that is parallel to the upper surface of the placement table 4 and intersects the moving direction of the placement table 4 (arrow X direction) at a right angle. .

  A frame 11 is held on the ball screw 9. The frame 11 is held by the ball screw 9 by screwing the ball screw 9 into a pair of holding pieces 11 a fixed to the upper side of the frame 11. The frame 11 moves along the axial direction (arrow Y direction) of the ball screw 9 as the ball screw 9 rotates.

  In the frame of the frame 11, a plurality of coating heads 12 are disposed along the arrow Y direction to eject a coating liquid (polyimide solution) that forms a functional thin film, for example, an alignment film, in the form of droplets by an ink jet method. Has been. In this embodiment, three coating heads 12 are arranged in a staggered manner.

  As shown in FIG. 4, the coating head 12 includes a head body 13. The head main body 13 is formed in a cylindrical shape, and the lower surface side opening portion is closed by a flexible plate 14. The flexible plate 14 is covered with a nozzle plate 15, and a plurality of liquid chambers 16 are formed between the nozzle plate 15 and the flexible plate 14.

  Each liquid chamber 16 communicates with a main pipe line 17 formed in the nozzle plate 15 via a branch pipe (not shown), and a coating liquid is supplied from the main pipe line 17 to the liquid chamber 16 via the branch pipe line. The The main pipeline 17 has one end connected to the liquid supply hole 18 and the other end connected to the recovery hole 19. The liquid supply hole 18 is connected to a supply tank (not shown) that stores the supplied coating liquid, and the recovery hole 19 is connected to a recovery tank (not shown) that stores the recovered coating liquid. That is, each coating head 12 can not only supply the coating liquid to the liquid chamber 16 and discharge it from the nozzle 20 but also collect the coating liquid in the liquid chamber 16 from the recovery hole 19.

  In the nozzle plate 15, a plurality of nozzles 20 are drilled along a direction (arrow Y direction) perpendicular to the transport direction (arrow X direction) of the substrate 6. On the upper surface of the flexible plate 14, a plurality of piezoelectric elements 21 that face the respective nozzles 20 are provided.

A driving voltage is applied to each piezoelectric element 21 by a piezoelectric element driving unit 22 provided in the head body 13. When this drive voltage is applied, the piezoelectric element 21 expands and contracts, the flexible plate 14 partially deforms, and the coating liquid in the liquid chamber 16 is liquidated from the nozzle 20 positioned facing the expanded piezoelectric element 21. It is ejected as dots in the form of dots. The liquid droplets ejected from the nozzle 20 are applied to the application region on the upper surface of the substrate 6 on the mounting table 4 that scans and moves in the direction of arrow X below the application head 12. Therefore, a coating pattern in which droplets are arranged in a dot shape is formed on the upper surface of the substrate 6. This application pattern adheres to each other as a single film by flowing and spreading the dot-like droplets.

  As shown in FIG. 5, the droplet applying apparatus 1 detects the discharge state of droplets discharged from each nozzle 20 of each coating head 12 (discharge presence / absence, discharge amount, discharge direction, discharge position, etc.). A camera 23 as a detection unit, an image processing unit 24 that processes a captured image that is a detection result by the camera 23, and the suitability of the discharge state of droplets from each nozzle 20 are determined based on the image-processed information. When it is determined that there is an improper nozzle whose function and droplet discharge state are not appropriate, the drive motor is arranged so that the improper nozzle is positioned away from the application region during the scanning movement for applying the droplet to the application region. 10 and a control unit 25 having a function of controlling 10 or the like. A total of three cameras 23 are provided, one for each coating head 12.

  A guide member 26 provided along the vertical direction (arrow Z direction) is fixed to the outer surface of the frame body 11, and a receiving member 27 is engaged with the guide member 26 so as to be slidable in the vertical direction. The camera 23 is fixed to 27. The receiving member 27 is driven by a driving unit (not shown) and can move in the vertical direction (arrow Z direction) along the guide member 26 together with the camera 23.

  When the coating liquid is applied onto the substrate 6 by each coating head 12, each camera 23 is moved to the position on the upper end side of the guide member 26 (the position indicated by the solid line in FIG. 1) and moved in the direction of the arrow X. The mounting table 4 is prevented from interfering with the camera 23.

  When detecting the discharge state of the droplets discharged from the nozzles 20 of the coating heads 12, first, the mounting table 4 is moved to the position indicated by the two-dot chain line in FIG. A liquid tank 29 attached to one end side in the X direction via an attachment member 28 is positioned below the coating head 12. Further, each camera 23 is moved to a detection work position on the lower end side of the guide member 26 (a position indicated by a two-dot chain line in FIG. 1), and the liquid droplets discharged from the nozzle 20 toward the liquid tank 29 are imaged by the camera 23. Try to be within the field of view. In this state, by ejecting droplets from the nozzle 20 toward the liquid tank 29, the droplets ejected from each nozzle 20 can be imaged by the camera 23. Here, it is assumed that the camera 23 has an imaging field of view that can take in droplets simultaneously discharged from all the nozzles 20 of the coating head 12. In addition, the imaging of the droplet by the camera 23 is performed by capturing a single droplet in flight by the stroboscopic imaging in accordance with the ejection timing of the droplet.

  The control unit 25 is a microcomputer including a CPU, a ROM, a RAM, and the like. As shown in FIG. 5, the ejection state suitability determination unit 30, the improper nozzle position determination unit 31, and the improper nozzle corresponding position determination unit. 32, an inappropriate nozzle correspondence number determination unit 33, a zero determination unit 34, an interruption signal output unit 35, a coating head movement position calculation unit 36, and a movement signal output unit 37.

The discharge state suitability determination unit 30 determines whether or not the discharge state of the droplets from the individual nozzles 20 is appropriate based on the information subjected to image processing by the image processing unit 24. For example, when a droplet is not ejected from the nozzle 20, when the ejection amount of the droplet ejected from the nozzle 20 is smaller than a reference amount, when the ejection direction of the droplet from the nozzle 20 is inclined, etc. It is determined that the droplet discharge state from the nozzle 20 is not appropriate. In other words, the ejection state suitability determination unit 30 determines whether or not a droplet (non-ejection) is not ejected depending on whether or not there are as many droplet images as the number of nozzles 20 included in the coating head 12 in the processed image by the image processing unit 24. Nozzle) 20 can be determined. In addition, it is possible to approximately calculate the amount of droplets ejected from each nozzle 20 based on the area and size of each droplet image in the processed image. further,
It is possible to determine whether or not the ejection direction of the droplets from the nozzle 20 is inclined depending on whether or not the interval between the droplet images in the processed image matches the arrangement interval of the nozzles 20.

  The improper nozzle position determination unit 31 determines the position of the nozzle (improper nozzle) 20 that has been determined that the droplet discharge state is not appropriate. For example, the improper nozzle 20 determines the number of the nozzle 20 from one end side of the coating head 12. The position of the improper nozzle 20 can be obtained based on the interval between the droplet images in the processed image. For example, when there is a non-ejecting nozzle (inappropriate nozzle) 20, the interval between the droplets is twice the arrangement interval of the nozzles 20 at the location corresponding to the improper nozzle 20. It can be determined that it exists.

  The improper nozzle corresponding position determination unit 32 determines whether or not the improper nozzle 20 determined by the improper nozzle position determination unit 31 is a nozzle corresponding to the application region.

  The improper nozzle correspondence number determination unit 33 determines the number of nozzles (inappropriate nozzles) 20 in which the ejection state of droplets corresponding to the application region of the substrate 6 is not appropriate when the application head 12 is moved. To do. For example, with reference to FIG. 6, the inappropriate nozzle correspondence number determination unit 33 performs the following determination. First, the coating head 12 is moved, that is, the positional relationship between the coating head 12 and the substrate 6 is set such that the leftmost nozzle 20 in the nozzle 20 row of the left coating head 12 is aligned in the arrow Y direction on the substrate 6. In the region “S”, the rightmost nozzle 20 in the row of nozzles 20 of the right coating head 12 from the state facing the left end of the left coating region “S” (state A) is the right coating region “S” on the substrate 6. The nozzle 20 is virtually shifted by an arrangement interval (pitch) until it reaches a state facing the right end portion (state B), and the number of improper nozzles 20a corresponding to the application region in each positional relationship is determined. Next, the minimum value is determined among the determined number of inappropriate nozzles 20a. In the case of FIG. 6, the number of improper nozzles 20a is “0” in the positional relationship shifted by 1 pitch from the state A and the positional relationship shifted by 2 pitches, and “1” in the other positional relationships. The “nozzle 20 corresponding to the application region” refers to the nozzle 20 that is positioned to face the application region of the substrate 6 in the vertical direction when the substrate 6 is scanned and passed below the application head 12. Means.

  The zero determination unit 34 determines whether or not the number of inappropriate nozzles 20 corresponding to the application region determined by the inappropriate nozzle correspondence number determining unit 33 is “0”.

  The interruption signal output unit 35 outputs an interruption signal for interrupting the subsequent operation for moving the coating head 12 when the determination result by the zero determination unit 34 is not “0”. In response to the output of the interruption signal, for example, a maintenance operation is performed to recover the improper nozzle (for example, as described in Patent Document 1, the coating liquid is pumped to the coating head and discharged from the nozzle to remove bubbles from the nozzle. Maintenance work) is performed. Alternatively, it is informed that there is an improper nozzle and prompts the user to recover the improper nozzle.

  The application head movement position calculation unit 36 calculates the movement position of the application head 12 at which the number of inappropriate nozzles corresponding to the application region is minimized according to the determination result of the inappropriate nozzle correspondence number determination unit 33.

  The movement signal output unit 37 outputs a movement signal based on the calculation result in the coating head movement position calculation unit 36 to the drive motor 10 to move the coating head 12 in the arrow Y direction.

Note that when applying the coating liquid to the substrate 6 after moving the coating head 12, droplets are ejected from which nozzle 20 of the coating head 12 and droplets are not ejected from which nozzle 20. Correct the discharge information. The ejection information is stored in the control unit 25 together with information on the driving voltage applied to the piezoelectric element 21 and the droplet ejection interval.

  The movement of the coating head 12 when the inappropriate nozzle 20a is generated will be described with reference to FIG.

  FIG. 6A shows a state where one improper nozzle 20 a is present in the coating head 12, and the improper nozzle 20 a corresponds to the coating region “S” of the substrate 6. In this case, in the positional relationship between the coating head 12 and the substrate 6 in the arrow Y direction, the smallest number (in this case, “0”) corresponding to the coating region “S” corresponds to the inappropriate nozzle. It is determined by the number determination unit 33. When the determination result is “0”, the application head movement position calculation unit 36 calculates the movement position of the application head 12 where the number of inappropriate nozzles corresponding to the application region “S” is “0”. In this example, in the initial state (the state shown in FIG. 6A), the positional relationship between the coating head 12 and the substrate 6 is such that the nozzle 20 located at the center of the central coating head 12 is located on the substrate 6. It is adjusted by the drive motor 10 so as to substantially coincide with the center position in the width direction (Y direction). In FIG. 6, the number of improper nozzles 20a is “0” depending on the positional relationship between the coating head 12 and the substrate 6 that is shifted by 1 pitch from the state A and the positional relationship that is shifted by 2 pitches. . Therefore, the coating head movement position calculation unit 36 obtains the movement position of the coating head 12 where the number of inappropriate nozzles is “0” as a position shifted by 3 pitches or 4 pitches in the right direction in the arrow Y direction from the initial state. be able to. When a plurality of movement positions are calculated, the application head movement position calculation unit 36 selects any one of the movement positions. For example, the application head movement position calculation unit 36 selects the movement position with the shortest movement distance from the initial state.

  When the calculation in the coating head movement position calculation unit 36 is performed, a movement signal based on the calculation result is output from the movement signal output unit 37 to the drive motor 10. The drive motor 10 rotates the ball screw 9, and the rotation of the ball screw 9 causes the coating head 12 to move by a predetermined dimension “L” in the direction of the arrow Y. As shown in FIG. The coating area “S” deviates. In this example, the predetermined dimension “L” is three times the arrangement interval (pitch) of the nozzles 20.

  A process for setting the position of the nozzle 20 will be described with reference to the flowchart of FIG. First, the liquid tank 29 is positioned below the coating head 12 indicated by the two-dot chain line in FIG. 1, and the camera 23 is positioned at the detection work position indicated by the two-dot chain line. Thereafter, droplets are ejected from each nozzle 20, the droplets are imaged by the camera 23 (step S1), and the captured image of the droplets captured by the camera 23 is subjected to image processing (step S2).

  Based on information obtained by image processing, whether or not the discharge state of the droplets from each nozzle 20 is appropriate (whether or not there is an inappropriate nozzle 20) is determined by the discharge state appropriateness determination unit 30. (Step S3). When the discharge state of the droplets from all the nozzles 20 is proper (when there is no improper nozzle 20) (NO in step S3), the coating head 12 is moved (the position of the nozzle 20 is newly set). ) Since there is no need, the process of setting the position of the nozzle 20 is completed.

  If there is an improper nozzle 20 (YES in step S3), the position of the improper nozzle 20 is determined by the improper nozzle position determination unit 31 (step S4).

When the position of the improper nozzle 20 is determined, whether or not the improper nozzle 20 is a nozzle corresponding to the application region is determined by the improper nozzle corresponding position determining unit 32 (step S5). If the improper nozzle 20 does not correspond to the application region (NO in step S5), that is, if the improper nozzle 20 is a nozzle 20 that is not used for applying the coating liquid to the application region of the substrate 6 this time, Since there is no hindrance to application, there is no need to move the application head 12 as in the case where NO is determined in step S3, and thus the processing for setting the position of the nozzle 20 ends.

  On the other hand, when it is determined that the improper nozzle 20 corresponds to the application region (YES in step S5), the number of improper nozzles 20 corresponding to the application region is minimized when the application head 12 is moved. The nozzle correspondence number determination unit 33 determines (step S6), and the zero determination unit 34 determines whether the minimum number is “0” (step S7).

  When the determination result in the zero determination unit 34 is not “0” (NO in step S6), an interruption signal that interrupts the subsequent operation of moving the coating head 12 is output from the interruption signal output unit 35 (step S8). The process for setting the nozzle position ends.

  When the zero determination unit 34 determines that the number of inappropriate nozzles 20 corresponding to the application region is “0” (YES in step S7), the inappropriate nozzle 20 is not allowed to correspond to the application region. The movement position of the application head 12 (the movement position of the application head 12 at which the number of inappropriate nozzles corresponding to the application area is “0”) is calculated by the application head movement position calculator 36 (step S9). For example, as shown in FIG. 6A, when it is determined that one nozzle corresponding to the application region “S” of the substrate 6 is the inappropriate nozzle 20 a, the inappropriate nozzle 20 a is applied to the substrate 6. The moving position of the coating head 12 (the position shown in FIG. 6B) so as not to correspond to the region “S” is calculated.

  After the movement position is calculated, a movement signal for moving the coating head 12 along the arrow Y direction toward the calculated movement position is output from the movement signal output unit 37 to the drive motor 10 (step S10). The drive motor 10 is driven based on the movement signal thus obtained (step S11), and the processing for setting the position of the nozzle 20 is completed by the movement of the coating head 12.

  After the movement of the coating head 12 is completed, the coating liquid is applied to the coating region of the substrate 6 by the moved coating head 12. In this coating operation, the substrate 6 is moved in the direction of arrow X by moving the mounting table 4 on which the substrate 6 is mounted from the position indicated by the two-dot chain line in FIG. This is performed by discharging droplets at a discharge amount (a set driving voltage is applied to the piezoelectric element 21) set from the nozzle 20 facing the application region and a discharge interval in accordance with the timing at which the application region passes. The droplets applied to the application region spread out and adhere to each other to be integrated, and an application film is formed on the application region of the substrate 6.

  If the zero determination unit 34 determines that the number of inappropriate nozzles 20a is not “0” (NO in step S7), the application liquid is not applied to the application region of the substrate 6 and is inappropriate. A maintenance operation is performed to recover the nozzle 20a. After the maintenance operation, steps S1 to S11 described above are executed.

  Therefore, according to this embodiment, when the improper nozzle 20 is generated, when the application can be executed without causing the improper nozzle 20a to correspond to the application region of the substrate 6, the droplet application operation is interrupted. The droplet application operation can be continued without performing the maintenance operation of the improper nozzle 20, and the opportunity to perform the maintenance operation can be reduced. As a result, the operating rate of the droplet applying apparatus 1 can be increased.

Further, since the application head 12 is moved by controlling the drive motor 10 so as to move the improper nozzle 20a to a position not corresponding to the application region of the substrate 6, the number of scanning movements required for applying the droplets to the application region is set. It is possible to perform application of droplets without increasing the number. Therefore, even if the inappropriate nozzle 20a occurs, without reducing the productivity,
Application can be performed.

In this embodiment, the case where the camera 23 is used as the detection unit for detecting the discharge state of the droplets discharged from each nozzle 20 has been described as an example. However, the detection unit is other than the camera 23. May be used. For example, a receiving member that receives droplets ejected from the nozzle and a sensor that detects information (amount and size) of the droplets attached to the receiving member may be used.
(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIGS. Note that in this embodiment and other embodiments described below, the same components as those described in the first embodiment are denoted by the same reference numerals, and redundant descriptions are omitted.

  The appearance configuration of the droplet coating apparatus according to the second embodiment is the same as that of the droplet coating apparatus 1 according to the first embodiment, and the second embodiment is different from the first embodiment in that This is the configuration of the control unit 25A.

  The control unit 25A is a microcomputer including a CPU, a ROM, a RAM, and the like. As shown in FIG. 8, the discharge state suitability determination unit 30 and the improper nozzle position determination unit 31 described in the first embodiment. A non-appropriate nozzle corresponding position determination unit 32, an improper nozzle corresponding number determination unit 33, a zero determination unit 34, a coating head movement position calculation unit 36, and a movement signal output unit 37, and an interruption signal output unit Instead of 35, a droplet discharge stopping unit 38 and a droplet discharge amount increasing unit 39 are provided.

  The application head moving position calculation unit 36 has the smallest number of improper nozzles corresponding to the application region (in the case of “0” or other than “0”) according to the determination result in the inappropriate nozzle correspondence number determination unit 33. The movement position of the coating head 12 is calculated.

  The droplet discharge stop unit 38 is a droplet from the improper nozzle 20 that corresponds to the coating region when the coating head 12 is moved to the movement position obtained by the calculation of the coating head movement position calculation unit 36. Set to stop discharging. In this case, in accordance with the movement position of the application head 12, in addition to the nozzles 20 not corresponding to the application region, the control unit 25A stores the droplets from the improper nozzle 20 corresponding to the application region. The discharged discharge information is corrected.

  The droplet discharge amount increasing unit 39 is positioned adjacent to the improper nozzle 20 where the droplet discharge is stopped by the droplet discharge stop unit 38, and the droplet discharge amount from the appropriate nozzle 20 corresponding to the application region. Set to increase. In this case, the voltage applied to the piezoelectric element 21 is applied only to the piezoelectric element 21 of the appropriate nozzle 20 located next to the inappropriate nozzle 20 corresponding to the application region, compared to the piezoelectric elements 21 of the other appropriate nozzles 20. The information regarding the drive voltage of the piezoelectric element 21 stored in the control unit 25A is corrected so that the voltage is increased by a predetermined amount.

  The movement of the coating head 12 and the discharge state of droplets from the nozzle 20 when a plurality of inappropriate nozzles 20a and 20b are generated will be described with reference to FIG.

  FIG. 9A shows a state where two improper nozzles 20 a and 20 b correspond to the application region “S” of the substrate 6. In this case, as described above, it is determined whether or not the application head 12 can be positioned so that only the appropriate nozzles 20 excluding the inappropriate nozzles 20a and 20b correspond to the application region “S”. In the case where it is impossible, it is determined whether or not any one of the inappropriate nozzles 20a can be arranged so as not to correspond to the application region “S”.

FIG. 9B shows that the number of improper nozzles corresponding to the application region “S” is the smallest (in this case 1).
The movement position of the application head 12 is calculated, and the application head 12 is moved to the movement position. The coating head 12 moves the dimension “L” in the direction of the arrow Y, and one inappropriate nozzle 20a is out of the coating area “S”, and only the other inappropriate nozzle 20b corresponds to the coating area “S”.

  9C, after the coating head 12 is moved to the movement position shown in FIG. 9B, the substrate 6 is transported in the direction of the arrow X and the coating liquid is discharged to the coating region “S”. The situation is shown. In this case, the ejection of droplets from the improper nozzle 20b corresponding to the application region “S” is stopped, and the ejection amount of droplets from the appropriate nozzle 20 located on both sides of the improper nozzle 20b is 50%. Has been increased.

  By stopping the discharge of droplets from the improper nozzle 20b and increasing the discharge amount of droplets from the appropriate nozzle 20 located on both sides by 50%, the amount of droplets applied in the application region is reduced. The target amount can be maintained, and the thickness of the film formed by adhering droplets applied in the application region can be the same as the film thickness of the other application regions.

  Accordingly, two (plural) inappropriate nozzles 20a and 20b are generated in the coating head 12, and even if the coating head 12 is moved, one (some) inappropriate nozzles 20b correspond to the coating region. On the other hand, when the application can be executed without causing the other (remaining) improper nozzle 20a to correspond to the application region of the substrate 6, the maintenance operation of the improper nozzles 20a and 20b for interrupting the droplet application operation is not performed. The droplet application operation can be continued, and the opportunity for performing the maintenance operation can be reduced. As a result, the operating rate of the droplet applying apparatus 1 can be increased.

  The process for setting the position of the nozzle 20 will be described with reference to the flowchart of FIG. The processing from step S1 to step S7 and from step S9 to step S11 is performed in the same manner as in the first embodiment shown in FIG.

  In step S1, an image of a droplet discharged from each nozzle 20 is captured by the camera 23. In step S2, a captured image of the droplet captured by the camera 23 is subjected to image processing. In step S3, a droplet from each nozzle 20 is processed. It is determined whether or not the discharge state is appropriate, and if there is an inappropriate nozzle 20 whose discharge state is inappropriate, the position of the inappropriate nozzle 20 is determined in step 4 and the position of the inappropriate nozzle 20 is determined. Then, it is determined in step S5 whether or not the inappropriate nozzle 20 is a nozzle corresponding to the application region.

  In step S6, the number of improper nozzles 20 corresponding to the application region in each positional relationship in which the positional relationship between the coating head 12 and the substrate 6 is virtually shifted by the arrangement interval (pitch) of the nozzles 20 in the arrow Y direction. Determine. In the example of FIG. 9, when the number of improper nozzles 20 corresponding to the application region is “0”, there is no “1” or “2”.

When the determination result in the zero determination unit 34 is not “0” (NO in step S7), the movement position of the coating head 12 at which the number of improper nozzles 20 corresponding to the coating area is minimized is the coating head movement position calculation. Calculated by the unit 36 (step S12). In the example of FIG. 9, the minimum value of the number of inappropriate nozzles 20 corresponding to the application region is “1”. That is, from the state (initial state) shown in FIG. 9A, the coating head 12 is moved to the right in the arrow Y direction, and the nozzle 20 is disposed at intervals of 1 to 6 pitches in the interval of the nozzles 20 to correspond to the coating region. , 20b is “1”. More specifically, the improper nozzle 20b does not correspond to the application area while the improper nozzle 20b corresponds to the application area while moving from the initial state to the right in the arrow Y direction by 1 to 3 pitches, but the improper nozzle 20a does not correspond to the application area. While the non-appropriate nozzle 20a corresponds to the application area during the 6-pitch movement, the improper nozzle 20b does not correspond to the application area, and the improper nozzle 20 corresponds to the application area.
The number of a and 20b is “1”.

  At this time, the application head movement position calculation unit 36 needs to select the movement position of the application head 12 from the movement positions of 1 to 6 pitches. This selection is performed as in the first embodiment. What is necessary is just to select what the movement distance of the coating head 12 becomes the shortest.

  After the movement position of the coating head 12 is calculated, when the coating head 12 moves to the movement position, the droplet discharge stop unit stops the discharge of the droplet from the improper nozzle 20 corresponding to the coating region. 38 is set (step S13). Further, the droplet discharge amount increasing unit 39 is set so as to increase the droplet discharge amount from the appropriate nozzle 20 corresponding to the application region and located next to the inappropriate nozzle 20 where the droplet discharge is stopped. (Step S14).

  After the processing of step S12 to step S14 is performed, a movement signal for moving the coating head 12 to the movement position calculated in step S12 is output to the drive motor 10 (step S10), and based on the output movement signal. The drive motor 10 is driven (step S11), and the process of setting the position of the nozzle 20 is completed by the movement of the coating head 12 according to the drive.

The number of improper nozzles 20 determined to correspond to the application area in step S5 described above is compared with the minimum value of the number of improper nozzles 20 corresponding to the application area calculated in step S12. If the latter number (minimum value) does not become smaller than the former number, the subsequent processing such as the application of droplets to the application region of the substrate 6 is interrupted, and the maintenance work for the improper nozzle is executed. Anyway.
(Third embodiment)
A third embodiment of the present invention will be described with reference to FIGS.

  The appearance configuration of the droplet coating apparatus of the third embodiment is the same as that of the droplet coating apparatus 1 of the first embodiment, and the third embodiment is different from the first embodiment in that It is the structure of the control part 25B.

  The control unit 25B is a microcomputer including a CPU, a ROM, a RAM, and the like, and as illustrated in FIG. 11, the ejection state suitability determination unit 30 and the inappropriate nozzle position determination unit 31 described in the first embodiment. A non-appropriate nozzle corresponding position determination unit 32, an improper nozzle corresponding number determination unit 33, a zero determination unit 34, a coating head movement position calculation unit 36, and a movement signal output unit 37, and an interruption signal output unit Instead of 35, a first application condition setting unit 40 and a second application condition setting unit 41 are provided.

  In the present embodiment, after the application head 12 is moved to the moving position where the number of improper nozzles 20 corresponding to the application region is minimized, there is still an improper nozzle 20 corresponding to the application region. That is, when the minimum value of the number of improper nozzles 20 by the improper nozzle correspondence number determination unit 33 is “1” or more, the liquid droplets are applied to the application region between the first application and the second application. Do this in two steps.

  When the improper nozzle 20 corresponds to the application area after moving the application head 12 to the moving position, the first application condition setting unit 40 stops the ejection of droplets from the improper nozzle 20 corresponding to the application area. At the same time, the application conditions for the first application are set so that the droplets are ejected from the appropriate nozzle 20 corresponding to the application region.

FIG. 12A shows the application region “S” of the substrate 6 on which the first application is performed according to the setting of the first application condition setting unit 40. In the first application, since the droplets are not discharged from the inappropriate nozzle 20b corresponding to the application region “S”, the linear region “W” in which the droplets are not applied to a part of the application region “S”. "Occurs.

  The second application condition setting unit 41 performs the first application so that the proper nozzle 20 corresponds to the linear region where the droplet is not applied corresponding to the improper nozzle 20 at the first application. The application conditions for the second application are set so that the application head 12 is moved and the droplets are ejected only from the appropriate nozzles 20 corresponding to the linear regions where the droplets were not applied during the first application.

  FIG. 12B shows the application region “S” of the substrate 6 where the second application is performed according to the setting of the second application condition setting unit 41. In the second application, the application head 12 is moved so that the appropriate nozzle 20 corresponds to the linear region generated during the first application. In this case, the coating head 12 is moved by one pitch of the nozzle 20 in the Y direction from the state shown in FIG. After moving the coating head 12, droplets are discharged only from the appropriate nozzle 20 corresponding to the linear area “W” where the droplets were not applied in the first application. By performing the first application and the second application, the droplets are uniformly applied to the entire droplet application region “S”.

  A process for setting the position of the nozzle 20 will be described with reference to the flowchart of FIG. The processing from step S1 to step S7 and from step S9 to step S11 is performed in the same manner as in the first embodiment shown in FIG.

  When the determination result in the zero determination unit 34 is not “0” (NO in step S7), the movement position of the coating head 12 at which the number of improper nozzles 20 corresponding to the coating area is minimized is the coating head movement position calculation. Calculated by the unit 36 (step S12).

  Then, as conditions for performing the first application of the droplets at the moving position, the ejection of the droplets from the improper nozzle 20 corresponding to the application region is stopped, and from the appropriate nozzle 20 corresponding to the application region. Discharging the droplet is set by the first application condition setting unit 40 (step S15).

  Furthermore, as a condition for performing the second application, as shown in FIG. 12, the appropriate nozzle 20 corresponds to a linear region where no droplets were applied corresponding to the inappropriate nozzle 20 at the first application. The second application condition setting unit 41 sets the movement of the coating head 12 so that the droplet is discharged only from the appropriate nozzle 20 corresponding to the linear region (step S16).

  After the processing of step S15 to step S16 is performed, a movement signal for moving the coating head 12 to the movement position calculated in step S12 is output to the drive motor 10 (step S10), and based on the output movement signal. The drive motor 10 is driven (step S11), and the coating head 12 scans and moves according to the drive, thereby completing the process of setting the position of the nozzle 20.

  After the coating head 12 is moved to the moving position by driving the drive motor 10 in step S10, the substrate 6 is transported in one direction, so that the coating conditions shown in FIG. As shown in a), droplet application is performed. Thereafter, the substrate 6 is scanned and moved in the reverse direction, whereby droplets are applied according to the application conditions set by the second application condition setting unit 41 as shown in FIG.

In the above embodiment, the case where the coating head 12 and the substrate 6 are scanned and moved relative to each other in the direction intersecting the arrangement direction of the nozzles 20 has been described as an example. However, the present invention is not limited to this, and even if the coating head 12 is scanned and moved, both the substrate 6 and the coating head 12 are scanned and moved (for example, both are simultaneously scanned in the opposite direction). May be.

  In addition, as a case where the coating head 12 and the substrate 6 are relatively moved in the arrangement direction of the nozzles 20, the coating head 12 is moved and the improper nozzle 20 is positioned at a position not corresponding to the coating region. However, the present invention is not limited to this, and a moving device for moving the mounting table 4 in the arrow Y direction may be added to move the mounting table 4, that is, the substrate 6 in the arrow Y direction.

1 droplet application device 6 substrate (application object)
10 Drive motor (movement drive unit)
12 Coating head 20 Nozzle 23 Camera (detection unit)
25 control unit 25A control unit 25B control unit

Claims (8)

This scanning is performed by relatively moving a coating head provided with a plurality of nozzles for discharging coating liquid droplets arranged in a predetermined direction and a substrate having a coating region in a direction intersecting the nozzle arrangement direction. In a droplet coating apparatus that applies droplets of a coating liquid to the coating region by ejecting droplets from the nozzle facing the coating region during movement,
A detection unit for detecting a discharge state of droplets from the nozzle;
A movement drive unit that relatively moves the coating head and the substrate in the arrangement direction of the nozzles;
A control unit for controlling the movement drive unit based on the detection result of the detection unit,
The controller is
Based on the detection result of the detection unit, the suitability of the discharge state of the droplets from each nozzle is determined, and when it is determined that there is an improper nozzle whose droplet discharge state is not appropriate, the liquid is applied to the application region. A droplet coating apparatus that controls the movement driving unit so that the improper nozzle is positioned out of the coating region during the scanning movement for coating a droplet.   2. The liquid according to claim 1, wherein when it is determined that the improper nozzle cannot be removed from the application region, the control unit interrupts execution of droplet application to the application region of the substrate. Drop application device.   When the control unit determines that the inappropriate nozzle cannot be removed from the application region, the controller stops discharging droplets from the inappropriate nozzle facing the application region during the scanning movement, and The droplet coating apparatus according to claim 1, wherein the droplet discharge amount from the nozzle in which the droplet discharge state adjacent to the appropriate nozzle is appropriate is increased.   When it is determined that the improper nozzle cannot be removed from the application area, the control unit stops the ejection of droplets from the improper nozzle facing the application area during the scanning movement. The application of droplets to the application area is performed, and then the movement drive unit is controlled so that the nozzle having an appropriate discharge state is positioned at the position of the inappropriate nozzle, and the application is performed using the appropriate nozzle. 2. The droplet coating apparatus according to claim 1, wherein the droplet coating is performed on the region. This scanning is performed by relatively moving a coating head provided with a plurality of nozzles for discharging coating liquid droplets arranged in a predetermined direction and a substrate having a coating region in a direction intersecting the nozzle arrangement direction. In a droplet application method of applying a droplet of a coating liquid to the application region by discharging a droplet from the nozzle facing the application region during movement,
Detecting a discharge state of a droplet discharged from each of the nozzles;
Determining whether or not the discharge state of the droplets discharged from the individual nozzles is appropriate;
When there is an improper nozzle in which the droplet discharge state is not appropriate, the improper nozzle is positioned away from the application region during the scanning movement for applying the droplet to the application region. Relatively moving the coating head and the substrate in the nozzle arrangement direction;
A droplet coating method comprising: Determining whether the improper nozzle can be removed from the application area;
When the improper nozzle cannot be removed from the application area, interrupting the execution of droplet application to the application area of the substrate;
The droplet coating method according to claim 5, further comprising: Determining whether the improper nozzle can be removed from the application area;
When the improper nozzle cannot be removed from the application area, the ejection of droplets from the improper nozzle facing the application area is stopped during the scanning movement, and the liquid droplet adjacent to the improper nozzle is stopped. Increasing the discharge amount of liquid droplets from the nozzle having an appropriate discharge state;
6. The droplet coating method according to claim 5, further comprising: Determining whether the improper nozzle can be removed from the application area;
When the improper nozzle cannot be removed from the application area, the liquid droplets are applied to the application area in a state where ejection of the liquid droplets from the improper nozzle facing the application area is stopped during the scanning movement. A step of performing the application of
A step of applying droplets to the application region using the appropriate nozzle after relatively moving the application head and the substrate so that a nozzle having an appropriate discharge state is positioned at the position of the inappropriate nozzle. When,
The droplet coating method according to claim 5, further comprising: