JP2013043136A - Coating liquid coating device and coating liquid coating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating liquid coating device and a coating liquid coating method which can accurately control a coating amount of coating liquid by adjusting a flow rate of the coating liquid in a short time.SOLUTION: Before coating with the coating liquid, a preparation process of preparing and storing beforehand a relational expression indicating a relationship between a width of a coating track and a flow rate of the coating liquid discharged from each nozzle is practiced. With respect to each practice of coating or with respect to each fixed period, a coating track measurement process of measuring the width of the coating track formed by continuously discharging the coating liquid to a test coating region is practiced. During coating of a glass substrate with the coating liquid, the opening of each flow control valve 74 is adjusted by utilizing the flow rate value of the coating liquid measured by each branch pipe flowmeter 75, the width of the coating liquid measured in the coating track measurement process and the relational expression stored beforehand, so as to make the coating amount of the coating liquid appropriate.

Description

  The present invention is a coating that applies a coating solution to a substrate such as a glass substrate for an organic EL display device, a glass substrate for a liquid crystal display device, a glass substrate for a PDP, a substrate for a solar cell, a substrate for electronic paper, or a mask substrate for a semiconductor manufacturing apparatus. The present invention relates to a liquid coating apparatus and a coating liquid coating method.

  For example, when manufacturing an active matrix driving type organic EL display device using a polymer organic EL (Electro Luminescence) material, a TFT (Thin Film Transistor) circuit is formed on a glass substrate, and an ITO (anode) is used as an anode. Indium Tin Oxide) electrode forming step, partition wall forming step, flowable material coating step including hole transport material, hole transport layer forming step by heat treatment, flowable material including organic EL material coating step, An organic EL layer forming step by heat treatment, a cathode forming step, and a sealing step by forming an insulating film are sequentially performed.

  When manufacturing such an organic EL display device, the coating liquid is continuously applied as a coating liquid coating apparatus that coats a coating liquid such as a fluid material containing a hole transport material or a fluid material containing an organic EL material on a substrate. 2. Description of the Related Art There is known an apparatus that applies a coating liquid in a stripe shape to a coating region on a substrate by moving a plurality of nozzles to be ejected relative to the substrate in a main scanning direction and a sub scanning direction.

  By the way, in such a coating liquid coating apparatus, when there is unevenness in the coating amount of the coating liquid, display unevenness of the display device and the like are caused accordingly. Need to control.

  For this reason, in Patent Document 1, a supply unit that supplies the coating liquid, a plurality of nozzles that discharge the coating liquid, and a plurality of coating liquids that are supplied from the processing liquid supply unit via the main pipe are connected to the nozzles. A branch part that divides into the branch pipe, a reference flow meter that measures the flow rate of the coating liquid that flows through the main pipe, and a flow rate of the coating liquid that flows through the branch pipes. In a coating liquid coating apparatus comprising a plurality of branch pipe flowmeters to be measured and a plurality of flow rate control valves for adjusting the flow rate of a coating liquid that is arranged in each branch pipe and flows through each branch pipe, an actual discharge flow rate and a reference A relational expression indicating the relationship between the flow rate measurement value of the flow meter and a relational expression indicating the relationship between the flow rate measurement value of the reference flow meter and the flow rate measurement value of the branch flow meter are obtained, and the flow rate is calculated using these relational expressions. Disclosed is a coating liquid coating apparatus that controls a control valve. That. In the coating liquid coating apparatus described in Patent Document 1, the flow rate of the coating liquid can be accurately controlled by calibrating the flow rate of the coating liquid.

JP 2009-45574 A

  The coating liquid coating apparatus described in Patent Document 1 described above is excellent in that the flow rate of the coating liquid discharged from each nozzle can be easily calibrated. However, as the number of nozzles increases in recent years, it takes time to adjust the flow rate. The problem that it takes is occurring. That is, with the recent increase in size of the substrate, the number of nozzles mounted on the coating liquid coating apparatus is increasing. In the coating liquid coating apparatus described in Patent Document 1, time required for calibration is required in proportion to the number of nozzles, so that the time required for calibration work becomes extremely long as the number of nozzles increases, The problem of reducing productivity arises. On the other hand, when flow control is performed using a flow meter and a flow control valve, there arises a problem that accurate flow control cannot be performed if the flow rate fluctuates due to changes over time and the calibration frequency decreases.

  The present invention has been made in order to solve the above-described problem, and a coating liquid coating apparatus and a coating liquid coating method capable of accurately controlling the coating amount of the coating liquid by adjusting the flow rate of the coating liquid in a short time. The purpose is to provide.

  According to the first aspect of the present invention, there is provided a coating liquid reservoir that stores a coating liquid, a plurality of nozzles that discharge the coating liquid, and a coating liquid that is supplied from the coating liquid reservoir through a main pipe. A branch portion for branching to a plurality of branch pipes connected to the plurality of branch pipes, a plurality of branch pipe flowmeters each arranged on the branch pipe for measuring the flow rate of a coating liquid flowing through the branch pipes, and each branch pipe arranged on the branch pipes. A plurality of flow rate control valves for adjusting the flow rate of the coating liquid flowing through the branch pipe, wherein the coating liquid is continuously discharged from the plurality of nozzles to the test coating region. Storage means for storing a relational expression indicating the relationship between the width or cross-sectional shape of the formed application locus and the flow rate of the application liquid discharged from the nozzle, and the application liquid continuously from the nozzle to the test application area. Formed by discharging An application locus measuring means for measuring the width or cross-sectional shape of the applied locus, a relational expression stored in the storage means when applying the application liquid to the substrate, a flow rate value of the application liquid measured by the branch flowmeter, And a control unit that controls the opening degree of the flow rate control valve based on the width or cross-sectional shape of the application locus measured by the application locus measurement means.

  According to a second aspect of the present invention, in the first aspect of the invention, the application trajectory measuring unit calculates a width of the application trajectory from a camera that images the application trajectory and an application trajectory imaged by the camera. An image processing unit for measurement.

  According to a third aspect of the present invention, in the second aspect of the present invention, the camera shoots a plurality of application trajectories ejected from a plurality of nozzles collectively.

  According to a fourth aspect of the present invention, there is provided a coating liquid storage section for storing a coating liquid, a plurality of nozzles for discharging the coating liquid, and a coating liquid supplied from the coating liquid storage section via a main pipe. A branch portion for branching to a plurality of branch pipes connected to the plurality of branch pipes, a plurality of branch pipe flowmeters each arranged on the branch pipe for measuring the flow rate of a coating liquid flowing through the branch pipes, and each branch pipe arranged on the branch pipes. A coating liquid coating method in a coating liquid coating apparatus for coating the substrate with a coating liquid, the flow rate of the coating liquid flowing through the branch pipe being adjusted, and the coating liquid is continuously supplied from the plurality of nozzles. From the measured value of the flow rate of the coating liquid with the branch flow meter at that time and the weight of the coating liquid discharged from the nozzle, the measured value of the flow rate of the coating liquid with the branch flow meter and the First, showing the relationship with the actual flow rate The width or cross-sectional shape of the application locus formed by continuously discharging the application liquid from the plurality of nozzles to the test application area, and the flow rate of the application liquid by the branch flow meter at that time From the measured value, a second relational expression representing the relationship between the width or cross-sectional shape of the coating trajectory and the measured value of the flow rate of the coating liquid by the branch flowmeter is obtained, and from the first relational expression and the second relational expression, A preparatory step for obtaining a third relational expression indicating the relationship between the width or cross-sectional shape of the coating locus and the flow rate of the coating solution, and before applying the coating solution to the substrate, the coating solution is applied from the nozzle to the test coating region. An application trajectory measuring step for measuring the width or cross-sectional shape of the application trajectory formed in the test application region, and the preparation step when applying the application liquid to the substrate Seeking Based on the third relational expression, the width or cross-sectional shape of the application locus measured in the application locus measurement process, and the measured value of the flow rate of the application liquid by the branch flow meter, the opening degree of each flow control valve is determined. And a coating process to be controlled.

  According to the first and fourth aspects of the invention, it is possible to accurately control the coating amount of the coating liquid by adjusting the flow rate of the coating liquid in a short time.

  According to the second aspect of the present invention, it is possible to easily and accurately recognize the flow rate of the coating liquid by measuring the width of the coating locus using a camera.

  According to the third aspect of the present invention, it becomes possible to collectively recognize the flow rate of the coating liquid from the plurality of nozzles, and it is possible to shorten the time required for adjusting the flow rate of the coating liquid. Further, the flow rate of the coating liquid applied from each branch pipe can be accurately controlled.

1 is a plan view of a coating liquid coating apparatus according to the present invention. It is a front view of the coating liquid coating apparatus which concerns on this invention. 4 is a cross-sectional view of the vicinity of a slider 31 in the head moving mechanism 21. FIG. FIG. 4 is a cross-sectional view seen from the side surface of the test application stage unit 16. FIG. 4 is a cross-sectional view seen from the front of the test application stage unit 16. It is a block diagram which shows the main control systems of the coating liquid coating apparatus which concerns on this invention. 3 is a schematic diagram showing a configuration of a coating liquid supply unit 24 and a connection relationship between the coating liquid supply unit 24 and a plurality of nozzles 23 in the coating head 20. FIG. It is a schematic diagram which shows the image of the application | coating locus | trajectory image | photographed with CCD camera 90. FIG. It is a graph which shows the relationship between the command signal to the flow control valve 74, and the width | variety of an application | coating locus | trajectory.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a plan view of a coating liquid coating apparatus according to the present invention, and FIG. 2 is a front view thereof.

  This coating solution coating apparatus is for coating a coating solution on a rectangular glass substrate 100. More specifically, the coating liquid coating apparatus includes a volatile solvent (in this embodiment, an aromatic organic solvent) on a glass substrate 100 for an active matrix driving type organic EL (Electro Luminescence) display device, And it is for apply | coating the coating liquid containing the organic electroluminescent material as a luminescent material.

  The coating liquid coating apparatus includes a substrate moving mechanism 11 for moving the glass substrate 100. As shown in FIG. 2, the substrate moving mechanism 11 includes a substrate holding unit 10 that holds the glass substrate 100 from its back surface. The substrate holding unit 10 is supported by a base 13 that moves along a pair of rails 12 and a turntable 14 disposed on the base 13. For this reason, this board | substrate holding | maintenance part 10 can move in parallel with the surface of the glass substrate 100 in the Y direction shown in FIG. This Y direction is a direction orthogonal to the main scanning direction (X direction in FIG. 1) which is the reciprocating direction of the coating head 20. Hereinafter, this Y direction is also referred to as “sub-scanning direction”. The substrate holding unit 10 is rotatable about an axis that faces in the vertical direction (Z direction in FIG. 1).

  The substrate holding unit 10 includes a heater for heating the glass substrate 100 from below. On the surface of the glass substrate 100, a plurality of application regions each extending in the X direction are arranged and formed in the Y direction at a pitch of, for example, 100 to 150 μm. This application region is formed by, for example, partition walls arranged in the X direction.

  In addition, the coating liquid coating apparatus includes a pair of left and right imaging units 15 for shooting and detecting an alignment mark (not shown) formed on the glass substrate 100 and shooting a coating locus by the coating head 20. Each of the pair of imaging units 15 is provided with a CCD camera 90 described later. In addition, the coating liquid coating apparatus includes a pair of left and right test coating stage units 16 used for test coating of the coating locus. In this coating liquid coating apparatus, the pitch of nozzles 23 to be described later is adjusted using the coating locus applied to the test coating stage 16 on a trial basis, and the feed control of the coating head 20 is adjusted as necessary. The structure to be adopted is adopted. In addition, in this coating liquid coating apparatus, a configuration is adopted in which the flow rate of the coating liquid is adjusted using a coating locus that has been experimentally applied to the test coating stage unit 16.

  The coating head 20 that discharges the coating liquid toward the surface of the glass substrate 100 held by the substrate holding unit 10 is moved in the main scanning direction (parallel to the surface of the glass substrate 100) along the guide unit 22 by the head moving mechanism 21. It is reciprocated in the X direction in FIG. In the coating head 20, a plurality of nozzles 23 for continuously discharging the same type of coating liquid are disposed at equal intervals in the sub-scanning direction. In FIG. 1 and FIG. 2, only five nozzles 23 are illustrated for convenience of illustration, but the number of nozzles 23 is further increased.

  The coating head 20 is connected to a coating liquid supply unit 24 and an air supply source 25 via a supply pipe group 26 that includes an air supply pipe and a plurality of branch pipes described later. On both sides of the substrate holding unit 10 with respect to the reciprocating movement direction (X direction) of the coating head 20, two liquid receiving portions 17 and 18 that receive the coating liquid from the nozzles 23 in the coating head 20 are disposed. Further, a nozzle pitch adjusting mechanism 19 for adjusting the pitch of the plurality of nozzles 23 in the sub-scanning direction is arranged on the side of one liquid receiving unit 18 in the reciprocating movement direction (X direction) of the coating head 20. It is installed.

  FIG. 3 is a sectional view of the vicinity of the slider 31 in the head moving mechanism 21.

  A slider 31 is slidably disposed on the guide member 22 in the head moving mechanism 21 shown in FIG. A through hole 32 through which the guide member 22 passes is formed in the slider 31. As shown in FIG. 1, air (gas) having a constant pressure is supplied to the slider 31 from an air supply source 25 through an air supply pipe included in the supply pipe group 26. For this reason, as shown in FIG. 3, air is jetted between the inner peripheral surface of the through hole 32 and the outer peripheral surface of the guide portion 22. In FIG. 3, the air ejection direction is indicated by an arrow denoted by reference numeral A <b> 1. Thereby, the slider 31 is supported so as to be movable in the main scanning direction while being engaged with the guide portion 22 in a non-contact state.

  Referring to FIG. 1, a pair of pulleys 33 that are rotatable around an axis that faces the Z-axis direction are disposed near both ends of the guide portion 22. An endless synchronous belt 34 is wound around the pair of pulleys 33. One end of the slider 31 is fixed to the synchronization belt 34. On the other hand, the application head 20 described above is fixed to the other end of the slider 31. Therefore, the application head 20 can be reciprocated in the (−X) direction or the (+ X) direction by rotating the synchronous belt 34 clockwise or counterclockwise by driving a motor (not shown). At this time, since the slider 31 can be supported in a non-contact state with respect to the guide portion 22 by the action of the gas described above, the reciprocating movement of the coating head 20 can be made fast and smooth. .

  In this coating liquid coating apparatus, the head moving mechanism 21 becomes a main scanning direction moving mechanism that moves the coating head 20 in the main scanning direction, and the substrate moving mechanism 11 moves in the sub scanning direction. It becomes a scanning direction moving mechanism. In this coating liquid coating apparatus, each time the movement of the coating head 20 in the main scanning direction is completed, the coating liquid is applied to the coating area on the surface of the glass substrate 100 by moving the glass substrate 100 in the sub scanning direction. The application of is performed. During main scanning of the coating head 20, acceleration or deceleration is completed in the vicinity of the liquid receiving portions 17 and 18, and the coating head 20 is, for example, at a constant speed of about 3 to 5 m per second above the glass substrate 100. Move with.

  Further, in this coating liquid coating apparatus, the pitch of nozzles 23 to be described later is adjusted using the coating trajectory applied to the test coating stage unit 16 on a trial basis, and the feed control of the coating head 20 is performed as necessary. The structure which adjusts is adopted. In addition, in this coating liquid coating apparatus, a configuration is adopted in which the flow rate of the coating liquid is adjusted using a coating locus that has been experimentally applied to the test coating stage unit 16.

  FIG. 4 shows a side view of one of the pair of left and right test application stage units 16 used for test application of the application trajectory for adjusting the pitch of the nozzles 23 or adjusting the flow rate of the application liquid. FIG. 5 is a cross-sectional view as seen from the front. In FIG. 4, the resin tape 41 is partially omitted.

  The test application stage unit 16 is configured to apply a coating liquid on the resin tape 41 on a trial basis by the application head 20 to form an application locus, and the imaging unit 15 takes an image of the application locus. As shown in FIGS. 4 and 5, the test application stage unit 16 includes a slider 42 slidably attached to the rail 12 of the substrate moving mechanism 11 and a housing 43 fixed on the slider 42.

  In the housing 43, a winding roller 44 for supplying a new resin tape 41, a winding roller 45 for winding the resin tape 41 coated with a coating liquid, and the winding roller 44 and the winding roller 45 are provided. In the meantime, a tape holding part 46 for holding the resin tape 41 on which the test application is performed is arranged. As shown in FIG. 4, the take-up roller 45 is connected to a worm gear 51 that rotates by driving of a motor 52. For this reason, the resin tape 41 is unwound from the unwinding roller 44 by the drive of the motor 52, and is wound around the winding roller 45.

  As shown in FIG. 4, the amount of the resin tape 41 taken up by the take-up roller 45 is detected by a sensor 48. Further, the end of the resin tape 41 unwound from the unwinding roller 44 is detected by a sensor 47.

  A coating liquid is applied to the resin tape 41 held by the tape holding unit 46 in the test coating stage unit 16 by the coating head 20 to form a coating locus. This application locus is photographed by a CCD camera 90 in the imaging unit 15 described later. The used resin tape 41 is taken up by a take-up roller 45 and collected. The resin tape 41 corresponds to the test application area according to the present invention.

  In the coating liquid coating apparatus having the above-described configuration, when the application of the coating liquid to the glass substrate 100 is started, the glass substrate 100 is first held by the substrate holding unit 10. And the alignment mark formed in the glass substrate 100 by the imaging part 15 is detected, the substrate holding | maintenance part 10 moves and rotates based on the detection result, and the glass substrate 100 is in the application | coating start position shown as a continuous line in FIG. Be placed. In this state, discharge of the coating liquid is started from the plurality of nozzles 23 in the coating head 20 and the coating head 20 is moved in the main scanning direction by the head moving mechanism 21.

  Then, the coating liquid is continuously discharged from each of the plurality of nozzles 23 toward the surface of the glass substrate 100 at a constant flow rate, and the coating head 20 continuously moves at a constant speed in the main scanning direction. Then, the coating liquid is applied in stripes to a plurality of linear regions in the coating region of the glass substrate 100.

  In this manner, the coating head 20 moves to the standby position facing the liquid receiving unit 18 indicated by a two-dot chain line in FIGS. 1 and 2, thereby forming a stripe pattern by the coating liquid. When the coating head 20 moves to the standby position, the substrate moving mechanism 11 is driven, and the glass substrate 100 moves in the sub-scanning direction together with the substrate holding unit 10. At this time, in the coating head 20, the coating liquid is continuously discharged from the plurality of nozzles 23 toward the liquid receiving unit 18.

  The above operation is continued until the necessary application operation is completed. Then, when the glass substrate 100 moves to the application end position, the discharge of the application liquid from the plurality of nozzles 23 is stopped, and the application operation of the application liquid to the glass substrate 100 by the application liquid application apparatus ends. The glass substrate 100 that has been coated is transported to another coating solution coating apparatus or the like, and two coating liquids other than the coating solution coated by the coating solution coating apparatus are applied. And after a predetermined application | coating process is performed with respect to the glass substrate 100, it combines with another component and an organic electroluminescent display apparatus is manufactured.

  FIG. 6 is a block diagram showing a main control system of the coating liquid coating apparatus according to the present invention.

  The coating liquid coating apparatus includes a control unit 60 that controls the entire apparatus. The control unit 60 is connected to the substrate moving mechanism 11, the turntable 14, the head moving mechanism 21, and the nozzle pitch adjusting mechanism 19 described above. The control unit 60 is connected to the flow rate control valve 70, the reference flow meter 72, the flow rate control valve 74, the branch flow meter 75, the open / close valve 76, the open / close valve 81, and the calibration unit 82 in the coating liquid supply unit 24. . The control unit 60 is connected to the above-described CCD camera 90 via the image processing unit 35. The image processing unit 35 measures the width of the application locus from the image of the application locus taken by the CCD camera 90. Further, although not shown, the control unit 60 includes a storage unit configured by a RAM, a ROM, and the like for executing various operations described later, and a calculation unit configured by a CPU. The control unit 60 may be configured by software using a general personal computer, or may be configured by hardware using a printed circuit board or the like.

  Next, the configuration of the coating liquid supply unit 24 will be described. FIG. 7 is a schematic diagram illustrating the configuration of the coating liquid supply unit 24 and the connection relationship between the coating liquid supply unit 24 and the plurality of nozzles 23 in the coating head 20.

  The coating liquid supply section 24 in the coating liquid coating apparatus according to the present invention includes a flow control valve 70, a coating liquid storage section 71, a reference flow meter 72, a manifold 73 as a branch section, and a plurality of flow control valves 74a. 74b, 74c,... 74n, a plurality of branch flow meters 75a, 75b, 75c,... 75n, a plurality of on-off valves 76a, 76b, 76c,. 82. Each of the open / close valves 76a, 76b, 76c,... 76n is connected to a plurality of nozzles 23a, 23b, 23c,.

  In this specification, if necessary, a plurality of flow control valves 74a, 74b, 74c,... 74n are collectively referred to as a flow control valve 74 and a plurality of branch flow meters 75a, 75b, 75c,. 75n is a generic name for the branch pipe flow meter 75, a plurality of on-off valves 76a, 76b, 76c... 76n is a generic name for the on-off valve 76, and a plurality of nozzles 23a, 23b, 23c. 23.

  Further, in this specification, a pipe line before branching from the coating liquid reservoir 71 to the manifold 73 via the flow rate control valve 70 and the reference flow meter 72 is referred to as a main pipe. In this specification, each flow control valve 74a, 74b, 74c,... 74n, each branch flow meter 75a, 75b, 75c,... 75n, each open / close valve 76a, 76b, 76c,. The branched pipe line that reaches each nozzle 23a, 23b, 23c... 23n through 76n is called a branch pipe. In this coating solution coating apparatus, there are a plurality of branch pipes corresponding to a to n.

  The coating liquid storage unit 71 has a configuration in which a flexible bag-like container storing the coating liquid is housed in an airtight chamber, and the flow rate control valve 70 controls the coating liquid by supplying pressurized air into the airtight chamber. In addition, it has a configuration in which it is pumped toward the reference flow meter 72, the manifold 73, and the like. The reference flowmeter 72 has a configuration for measuring the flow rate of the coating liquid discharged from the coating liquid storage unit 71 and flowing into the manifold 73. The reference flow meter 72 is a thermal flow meter that measures the flow rate of the coating liquid using a heater and a temperature sensor provided in the flow path of the coating liquid.

  Each flow control valve 74 receives a command from the control unit 60 shown in FIG. 6 and adjusts the flow rate of the coating liquid flowing through each branch pipe. Each branch flow meter 75 measures the flow rate of the coating liquid flowing through each branch pipe. As the branch flow meter 75, a thermal flow meter that measures the flow rate of the coating liquid using a heater and a temperature sensor is used as in the case of the reference flow meter 72. The measurement value of the flow rate by the branch flow meter 75 is transmitted to the control unit 60 shown in FIG. The flow control valve 74 and the branch pipe flow meter 75 constitute a mass flow controller. Further, each open / close valve 76 receives a command from the control unit 60 shown in FIG. 6 and opens or closes the flow path of each branch pipe. Similarly, the open / close valve 81 receives a command from the control unit 60 shown in FIG. 6 and opens or closes the flow path from the manifold 73 to the calibration unit 82.

  The calibration unit 82 includes a container in which the coating solution is stored and an electronic balance that measures the weight of the container in which the coating solution is stored. By measuring the amount of change in the weight of the container in which the coating liquid is stored with this electronic balance, the mass of the coating liquid flowing into the container can be measured, and thereby the discharge amount of the coating liquid can be specified. Become.

  Next, the operation of the coating liquid coating apparatus having the above configuration will be described. When applying the coating liquid with this coating liquid coating apparatus, a preparatory step for creating and storing in advance a relational expression indicating the relationship between the width of the coating locus and the flow rate of the coating liquid discharged from each nozzle 23 is performed. Run. Then, every time the application is performed or every certain period, an application locus measuring step for measuring the width of the application locus formed by continuously discharging the application liquid onto the resin tape 41 as the test application area. Execute. At the time of applying the coating liquid to the glass substrate 100, each flow rate value of the coating liquid measured by each branch flow meter 75, the width of the coating liquid measured in the coating trajectory measuring step, and the relational expressions stored in advance are used. By adjusting the opening degree of the flow control valve 74, the application amount of the application liquid is made appropriate.

  First, the preparation process will be described. In the preparation process, first, the reference flow meter 72 is calibrated. First, the opening / closing valve 81 is opened. At this time, pressurized air having a predetermined pressure is supplied to the coating liquid reservoir 71, and the coating liquid can be fed toward the manifold 73 via the flow control valve 70 and the reference flow meter 72. Yes. Moreover, the open / close valve 76 in each branch pipe is closed in advance. As a result, the coating liquid is pumped from the coating liquid storage section 71 toward the calibration section 82 via the flow rate control valve 70, the reference flow meter 72, the manifold 73, and the opening / closing valve 81, and is stored in the container by the calibration section 82. The Then, the flow value indicated by the reference flow meter 72 when the coating liquid is discharged into the container is acquired. Further, the weight of the coating liquid discharged into the container of the calibration unit 82 is measured by an electronic balance.

  Then, based on the weight of the coating liquid flowing per unit time measured using the electronic balance and the specific gravity of the coating liquid, the control unit 60 shown in FIG. Calculate the flow rate. Then, the actual flow rate is compared with the flow rate value indicated by the reference flow meter 72. Thereafter, the reference flow meter 72 is adjusted so that the flow rate value indicated by the reference flow meter 72 matches the actual flow rate value. Thereby, the flow value indicated by the reference flow meter 72 can be matched with the actual flow value of the coating liquid.

  Next, after one branch pipe is selected from the plurality of branch pipes, the flow rate value indicated by the reference flow meter 72 when the coating liquid is supplied only to the one branch pipe and the branch pipe to which the coating liquid is supplied. A relational expression indicating a relationship between the flow rate value indicated by the branch flow meter 75 is obtained. At this time, since the calibration of the reference flow meter 72 has been completed, the relational expression indicating the relationship between the flow value indicated by the branch flow meter 75 of the branch pipe and the flow value indicated by the reference flow meter 72 is expressed by the branch pipe of the branch pipe. This is equivalent to the first relational expression showing the relationship between the flow rate value indicated by the flow meter 75 and the actual flow rate of the coating liquid. When obtaining this first relational expression, measurement is performed at several points by changing the flow rate value of the coating liquid. In addition, this 1st relational expression is calculated | required for every branch pipe.

  Next, the coating solution is continuously discharged from each nozzle 23 onto the resin tape 41 in the test coating stage unit 16 as a test coating region. Then, the application locus formed on the resin tape 41 is photographed by the CCD camera 90. Thereafter, the width of the application locus is measured by the image processing unit 35.

  FIG. 8 is a schematic diagram showing an image of a coating locus photographed by the CCD camera 90. FIG. 8 shows a case where the coating locus discharged from the four nozzles 23 is photographed by the CCD camera 90 and the widths thereof are D1, D2, D3, and D4.

  The widths of these application trajectories and the corresponding branch flowmeters 75 when the application liquid is continuously discharged from the corresponding nozzles 23 to the resin tape 41 in the test application stage unit 16 to form application trajectories. Based on the measured value of the flow rate, a second relational expression representing the relationship between the width of the application trajectory and the measured value of the flow rate of the coating liquid by the branch flow meter 75 is obtained. When obtaining this second relational expression, measurement is performed at several points by changing the flow rate of the coating liquid. This second relational expression is also obtained for each branch pipe.

  Thereafter, the preparatory process is completed by obtaining a third relational expression indicating a relation between the width of the coating locus and the flow rate of the coating liquid based on the first relational expression and the second relational expression.

  FIG. 9 is a graph showing the relationship between the command signal to the flow control valve 74 and the width of the application locus.

  In this figure, the horizontal axis represents the command value (no unit) to the flow control valve 74, and the vertical axis represents the width (mm) of the application locus. The command value of the flow control valve 74 is proportional to the flow rate of the coating liquid. As shown in this graph, it can be understood that the flow rate of the coating liquid and the width of the coating locus are in a substantially proportional state.

  When the coating liquid is applied to the glass substrate 100, the application trajectory formed by continuously discharging the coating liquid to the resin tape 41 every time the application is performed or every certain period of time. An application trajectory measuring step for measuring the width is executed.

  In this case, the coating liquid is continuously discharged from the nozzles 23 to the resin tape 41 in the test coating stage unit 16 as in the preparation step described above. Then, the application locus formed on the resin tape 41 is photographed by the CCD camera 90. Thereafter, the width of the application locus is measured by the image processing unit 35. Thereby, the relationship between the width of the coating locus at that time and the measured value of the flow rate of the coating liquid by the branch pipe flowmeter 75 can be specified for each branch pipe. This corresponds to the calibration operation of the branch flow meter 75 at this time.

  The application locus measured by the CCD camera 90 at this time may be used for pitch adjustment of the plurality of nozzles 23 by the nozzle pitch adjustment mechanism 19.

  At the time of applying the coating liquid to the actual glass substrate 100, the flow rate value of the coating liquid measured by each branch flow meter 75, the width of the coating liquid measured in the coating locus measuring step, and the third relational expression stored in advance are obtained. The opening degree of each flow control valve 74 is adjusted using this.

  That is, the relationship between the width of the application trajectory and the flow rate of the application liquid is specified by the third relational expression, and the width of the application trajectory at that time and the flow rate of the application liquid by the branch flow meter 75 are determined by the application trajectory measurement step. Since the relationship between the measured values is specified, the relationship between the flow rate of the coating liquid at that time and the measured value of the flow rate of the coating liquid by the branch flow meter 75 can be obtained based on these pieces of information. Then, by correcting the opening degree of each flow rate control valve 74 based on this information, the flow rate of the coating liquid can be adjusted to an appropriate value.

  In the above-described embodiment, the discharge amount of the coating liquid is obtained based on the width of the application locus measured by the CCD camera 90. However, the discharge amount of the application liquid is obtained based on the cross-sectional shape of the application locus. May be. In this case, the cross-sectional shape of the application trajectory is measured by measuring the application trajectory with a white interferometer, or by measuring the application trajectory after the coating liquid has been dried by contact with a probe. The discharge amount of the coating liquid can be measured more accurately. However, when the thickness of the coating solution in the coating locus is constant regardless of the width, the discharge amount of the coating solution can be determined more easily by measuring the width of the coating solution.

DESCRIPTION OF SYMBOLS 10 Substrate holding part 11 Substrate moving mechanism 12 Rail 13 Base 14 Rotating table 15 Imaging part 16 Test application stage part 17 Liquid receiving part 18 Liquid receiving part 19 Nozzle pitch adjusting mechanism 20 Coating head 21 Head moving mechanism 22 Guide part 23 Nozzle 24 Coating liquid supply unit 25 Air supply source 31 Slider 32 Through-hole 33 Pulley 34 Synchronous belt 35 Image processing unit 42 Slider 43 Housing 41 Resin tape 44 Unwinding roller 45 Take-up roller 70 Flow control valve 71 Coating liquid storage unit 72 Reference flow meter 73 Manifold 74 Flow control valve 75 Branch flow meter 76 Open / close valve 81 Open / close valve 82 Calibration unit 60 Control unit 90 CCD camera 100 Glass substrate

Claims (4)

A coating liquid storage section that stores the coating liquid, a plurality of nozzles that discharge the coating liquid, and a coating liquid that is supplied from the coating liquid storage section via the main pipe is divided into a plurality of branch pipes connected to the nozzle Branching portions, a plurality of branch flow meters each measuring the flow rate of the coating liquid that flows through the branch pipes, and the flow rate of the coating liquid that flows through the branch pipes. A plurality of flow rate control valves to be adjusted, and a coating liquid coating apparatus comprising:
Relational expression showing the relationship between the width or cross-sectional shape of the application locus formed by continuously discharging the application liquid from the plurality of nozzles to the test application area, and the flow rate of the application liquid discharged from the nozzle Storage means for storing
Application trajectory measuring means for measuring the width or cross-sectional shape of the application trajectory formed by continuously discharging the application liquid from the nozzle to the test application area;
Based on the relational expression stored in the storage unit, the flow rate value of the coating solution measured by the branch pipe flowmeter, and the width or cross-sectional shape of the coating track measured by the coating track measuring unit when the coating solution is applied to the substrate. A control unit for controlling the opening of the flow control valve;
A coating liquid coating apparatus comprising: The coating liquid coating apparatus according to claim 1,
The application trajectory measuring unit includes a camera that captures the application trajectory, and an image processing unit that measures a width of the application trajectory from an image of the application trajectory captured by the camera. The coating liquid coating apparatus according to claim 2,
The camera is a coating liquid coating apparatus that photographs a plurality of coating tracks discharged from a plurality of nozzles at once. A coating liquid storage section that stores the coating liquid, a plurality of nozzles that discharge the coating liquid, and a coating liquid that is supplied from the coating liquid storage section via the main pipe is divided into a plurality of branch pipes connected to the nozzle Branching portions, a plurality of branch flow meters each measuring the flow rate of the coating liquid that flows through the branch pipes, and the flow rate of the coating liquid that flows through the branch pipes. A coating liquid coating method in a coating liquid coating apparatus that includes a plurality of flow rate control valves to adjust and coats a coating liquid on a substrate,
The application liquid is continuously discharged from the plurality of nozzles, and the application value by the branch flowmeter is measured from the measured value of the flow rate of the application liquid by the branch flowmeter at that time and the weight of the application liquid discharged from the nozzle. Obtain the first relational expression showing the relationship between the measured value of the flow rate of the liquid and the actual flow rate of the coating liquid,
From the width or cross-sectional shape of the coating locus formed by continuously discharging the coating solution from the plurality of nozzles to the test coating region, and the measured value of the flow rate of the coating solution by the branch flow meter at that time The second relational expression representing the relationship between the width or cross-sectional shape of the coating locus and the measured value of the flow rate of the coating solution by the branch flow meter is obtained,
From the first relational expression and the second relational expression, a preparation step for obtaining a third relational expression indicating the relation between the width or cross-sectional shape of the coating locus and the flow rate of the coating liquid;
Prior to applying the coating liquid to the substrate, the coating liquid is continuously discharged from the nozzle to the test application area to form an application locus, and the width or cross-sectional shape of the application locus formed in the test application area An application trajectory measurement process for measuring
When applying the coating solution to the substrate, the third relational expression obtained in the preparation step, the width or cross-sectional shape of the coating locus measured in the coating locus measurement step, and the flow rate of the coating solution measured by the branch flow meter And an application process for controlling the opening degree of each flow control valve based on the value,
A coating liquid coating method comprising:

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