KR100966214B1 - Coating apparatus - Google Patents

Abstract

Provided is a coating apparatus which can start discharging the coating liquid quickly and satisfactorily from a nozzle without increasing the consumption of the coating liquid, and also does not cause a problem of solvent shock.

The coating device 1 first discharges only the main solvent from the nozzle 31, and then gradually increases the ratio of the organic EL liquid, gradually decreases the ratio of the main solvent, and finally removes from the nozzle 31. Only organic EL liquid is discharged. For this reason, the foreign substance and the bubble which remain in the inside of the nozzle 31 can be discharged to the exterior of the nozzle 31 with a main solvent, and then the organic EL liquid can be discharged. Moreover, since it substitutes gradually with an organic EL liquid from a main solvent, the problem of a solvent shock does not arise either. In addition, since the discharge of the organic EL liquid can be started without repeating the cleaning of the nozzle 31 and the discharge of the organic EL liquid, the discharge of the organic EL liquid can be promptly started without increasing the consumption amount of the organic EL liquid. Can be.

Description

Coating device {COATING APPARATUS}

The present invention is applied to apply a coating liquid to the surface of various substrates 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 semiconductor wafer, and a glass / ceramic substrate for a magnetic / optical disk. Relates to a device.

In the manufacturing process of a board | substrate, the coating apparatus which apply | coats various coating liquids to the upper surface of a board | substrate is used. For example, in the manufacturing process of an organic electroluminescence display, the application | coating device which apply | coats an organic electroluminescent liquid on the upper surface of the glass substrate for organic electroluminescence display is used. The conventional coating apparatus is equipped with the nozzle for discharging coating liquid toward the upper surface of a board | substrate, and the moving mechanism for moving a nozzle and a board | substrate relatively, as disclosed, for example in patent document 1, 2 . The coating device applies the chemical liquid to the upper surface of the substrate by discharging the coating liquid from the pores formed in the nozzle in the form of a liquid column, and relatively moving the nozzle and the substrate while continuing to discharge the coating liquid.

[Patent Document 1] Japanese Patent Laid-Open No. 2006-192435

[Patent Document 2] Japanese Patent No. 376263

In the above coating apparatus, when foreign matter, bubbles, etc. remain in the inside of a nozzle or a discharge hole at the time of starting discharge of a coating liquid from a nozzle, the coating liquid may not be discharged satisfactorily from a nozzle. In particular, in the case of discharging a highly viscous coating liquid such as an organic EL liquid from a fine discharge hole, foreign matter or bubbles inside the nozzle are likely to cause "blocking" of the coating liquid, and also by the surface tension of the coating liquid. Since the coating liquid tended to diffuse around, it was difficult to form a satisfactory liquid column of the coating liquid under the nozzle.

In addition, when the discharge of the coating liquid from the nozzle is urgently started, so-called "solvent shock", in which the shape of the liquid column of the coating liquid collapses under the nozzle, tends to occur, and in particular, the diameter of the discharge hole. When using the nozzle which is 70 micrometers or less, it was very difficult to form a favorable liquid column below the nozzle.

Conventionally, when starting to discharge coating liquid from a nozzle, washing | cleaning of a nozzle and discharge of the coating liquid from a nozzle are repeated, and the state which favorable discharge of coating liquid from a nozzle was realized by this. However, in such a method, it takes a long time until the coating liquid is discharged satisfactorily, and the consumption amount of the coating liquid was also increased.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a coating apparatus which can start discharging the coating liquid from the nozzle quickly and satisfactorily without increasing the consumption amount of the coating liquid, and also does not cause a problem of solvent shock. It aims to do it.

In order to solve the said subject, invention of Claim 1 is a coating apparatus which apply | coats the coating liquid containing a to-be-coated substance and a predetermined organic solvent to the surface of a board | substrate, Comprising: It discharges the said coating liquid toward the surface of a board | substrate. A nozzle, a pipe portion connected to the nozzle, a coating liquid supply means for supplying the coating liquid to the piping portion, solvent supply means for supplying the organic solvent to the piping portion, the coating liquid supply means, and the A control means for controlling the solvent supply means, wherein the control means is a solvent supply operation for supplying the organic solvent from the solvent supply means in a state in which the supply of the coating liquid from the coating liquid supply means is stopped. And gradually reducing the supply amount of the organic solvent from the solvent supply means after the solvent supply operation, and the coating liquid supply means. And a substituting operation for gradually increasing the supply amount of the coating liquid from the above, and a coating liquid supplying operation for supplying the coating liquid from the coating liquid supplying means after the substitution operation.

In the invention according to claim 2, in the coating device according to claim 1, the control means includes, in the substitution operation, a supply amount of the organic solvent from the solvent supply means and the coating liquid from the coating liquid supply means. The supply of the organic solvent from the organic solvent supply means is stopped when the supply amount of is substantially the same.

The invention according to claim 3 is the coating device according to claim 2, wherein the coating liquid supplying means has a coating liquid piping and a mass flow controller for coating liquid provided on the coating liquid piping, and the solvent supplying means is used for a solvent. It has a piping and the solvent mass flow controller provided on the said solvent piping, The said control means performs the said substitution operation by controlling the said mass flow controller for coating liquid and the said mass flow controller for solvents.

The invention according to claim 4 is the coating device according to claim 3, wherein the coating liquid includes an organic EL material as the coating material.

The invention according to claim 5 is the coating device according to claim 4, wherein the nozzle discharges the coating liquid through a discharge hole having a diameter of 70 μm or less.

The invention according to claim 6 is a coating apparatus for applying a coating liquid containing a substance to be coated and a predetermined organic solvent to a surface of a substrate, comprising: a nozzle for discharging the coating liquid toward a surface of a substrate, and connected to the nozzle; To control the supplied piping portion, coating liquid supply means for supplying the coating liquid to the piping portion, solvent supply means for supplying the organic solvent to the piping portion, and control of the coating liquid supply means and the solvent supply means. And a control means, after the mixed liquid supply operation of supplying a small amount of the coating liquid from the coating liquid supply means, the supply of the organic solvent from the solvent supply means, and the mixed liquid supply operation, The supply amount of the organic solvent from the solvent supply means is gradually lowered while the supply amount of the organic solvent from the solvent supply means is supplied. And the substitution of motion gradually increases, characterized in that to the post-replacement operations, the execution of the coating liquid supply operation performed by the supply of the coating liquid from the coating liquid supplying means.

According to the invention of Claims 1 to 5, the coating device is a solvent supply operation for supplying an organic solvent from the solvent supply means in a state in which the supply of the coating liquid from the coating liquid supply means is stopped, and after the solvent supply operation, A coating operation which gradually reduces the supply amount of the organic solvent from the solvent supply means and gradually increases the supply amount of the coating liquid from the coating liquid supply means, and the coating which supplies the coating liquid from the coating liquid supply means after the substitution operation. Perform the liquid supply operation. For this reason, the foreign matter and air bubbles which remain in the inside of a nozzle can be discharged | emitted with the solvent to the exterior of a nozzle, and then a coating liquid can be discharged from a nozzle. In addition, since the liquid discharged from the nozzle is gradually replaced from the organic solvent to the coating liquid, the occurrence of so-called "solvent shock" in which the shape of the discharge liquid column collapses due to a sudden change in the concentration or viscosity of the liquid discharged from the nozzle. It can prevent. Therefore, discharge of a coating liquid can be started favorably from a nozzle. Moreover, since it is possible to start discharging the coating liquid without repeating the nozzle cleaning and discharging the coating liquid, the discharging of the coating liquid can be promptly started without increasing the consumption amount of the coating liquid.

In particular, according to the invention as set forth in claim 2, the coating device is organic solvent supplied when the supplying amount of the organic solvent from the solvent supplying means and the supplying amount of the coating liquid from the coating liquid supplying means are substantially the same in the substitution operation. The supply of the organic solvent from the means is stopped. For this reason, it can prevent that a coating liquid enters the solvent supply means side.

In particular, according to invention of Claim 3, the supply amount of the coating liquid from a coating liquid supply means and the supply amount of the solvent from a solvent supply means are controlled using a mass flow controller. For this reason, the supply amount of a coating liquid and a solvent can be controlled easily and correctly.

In particular, according to the invention described in claim 4, the highly viscous coating liquid containing the organic EL material can be appropriately discharged from the nozzle.

In particular, according to the invention described in claim 5, the nozzle discharges the coating liquid through a discharge hole having a diameter of 70 μm or less. In a nozzle having such a small diameter discharge hole, it is particularly difficult to form the discharge liquid column of the coating liquid satisfactorily. According to the present invention, the discharge liquid column can be formed satisfactorily.

Moreover, according to invention of Claim 6, a coating device is a solvent after the mixed liquid supply operation which supplies a small amount of coating liquid from a coating liquid supply means, the supply of the organic solvent from a solvent supply means, and a mixed liquid supply operation, Substitution operation which gradually reduces the supply amount of the organic solvent from the supply means and gradually increases the supply amount of the coating liquid from the coating liquid supply means, and the coating liquid which supplies the coating liquid from the coating liquid supply means after the substitution operation. Perform the feed operation. For this reason, the foreign matter or bubble which stays inside a nozzle can be discharged | emitted with the solvent to the exterior of a nozzle, and then a coating liquid can be discharged from a nozzle. In addition, since the liquid discharged from the nozzle is gradually replaced from the organic solvent to the coating liquid, the occurrence of so-called "solvent shock" in which the shape of the discharge liquid column collapses due to a sudden change in the concentration or viscosity of the liquid discharged from the nozzle. It can prevent. Therefore, discharge of a coating liquid can be started favorably from a nozzle. Moreover, since it is possible to start discharging the coating liquid without repeating the nozzle cleaning and discharging the coating liquid, the discharging of the coating liquid can be promptly started without increasing the consumption amount of the coating liquid.

EMBODIMENT OF THE INVENTION Hereinafter, preferred embodiment of this invention is described, referring drawings.

<1. Composition of Coating Device>

FIG. 1: is a top view which shows the structure of the coating device 1 which concerns on one Embodiment of this invention. 2 is a longitudinal cross-sectional view which cut | disconnected the coating device 1 with the II-I line of FIG. In each of these drawings, a common XYZ rectangular coordinate system is attached in order to clarify the positional relationship and the operation direction of each part in the apparatus.

In the process of manufacturing an organic electroluminescence display, the coating device 1 shown to FIG. 1 and FIG. 2 has an organic electroluminescent material (on the upper surface of the rectangular glass substrate (henceforth simply called a "substrate") 9 It is an apparatus for apply | coating the organic EL liquid which mixed the coating material) and a predetermined solvent. As shown in FIG. 1 and FIG. 2, the coating device 1 mainly includes the stage 10, the stage moving mechanism 20, the nozzle unit 30, the nozzle moving mechanism 40, and the atmospheric pod. 50, a recovery tray 60, and a control unit 70 are provided.

The stage 10 has a flat shape and is a holding part for holding and holding the substrate 9 in a horizontal posture on its upper surface. A plurality of suction holes (not shown) are formed in the upper surface of the stage 10. For this reason, when placing the board | substrate 9 on the stage 10, the board | substrate 9 is hold | maintained on the upper surface of the stage 10 by the suction pressure of a suction hole. On the upper surface of the substrate 9 placed on the stage 10, a plurality of parallel grooves 9a are formed in advance at the position where the organic EL liquid is applied. The substrate 9 is placed on the stage 10 so that these grooves 9a face the main scanning direction (X-axis direction).

Moreover, the mask plates 11 and 12 which cover the side part of the -X side and the + X side of the board | substrate 9 are arrange | positioned above the stage 10. As shown in FIG. The mask plates 11 and 12 prevent the organic EL liquid discharged from the nozzle unit 30, which will be described later, from being applied to the side portions of the + X side and the -X side of the substrate 9, and induce the organic EL liquid to the main scanning direction. It serves to define the application range of EL liquid. The mask plates 11 and 12 are fixedly attached to the stage 10 via predetermined connection members (not shown).

The stage moving mechanism 20 is a mechanism for moving the stage 10 in the sub scanning direction (Y-axis direction). The stage movement mechanism 20 is comprised by the mechanism which combined the motor and the ball screw, for example, or the mechanism which used the linear motor. When the stage movement mechanism 20 is operated with the substrate 9 placed on the stage 10, the stage 10, the mask plates 11, 12 and the substrate 9 are integrally scanned in the sub-scanning direction. Go to.

The nozzle unit 30 is a discharge unit for discharging the organic EL liquid toward the upper surface of the substrate 9 held on the stage 10. The nozzle unit 30 has three nozzles 31 for discharging the organic EL liquid for red, green, and blue. As shown in FIG. 1, the three nozzles 31 are arranged at predetermined intervals (for example, several mm pitch) in the main scanning direction, and are arranged so as to shift the position in the sub scanning direction little by little. The difference in position in the sub-scan direction of each nozzle 31 corresponds to the pitch width of the groove 9a formed on the upper surface of the substrate 9 to be processed. For this reason, the nozzle part 30 can discharge organic EL liquid simultaneously to three adjacent groove | channels 9a on the board | substrate 9 by simultaneously discharging organic EL liquid from three nozzles 31. As shown in FIG. have.

Thus, this coating device 1 can apply | coat an organic EL liquid three columns on the board | substrate 9 using three nozzles 31. As shown in FIG. For this reason, an organic EL liquid can be apply | coated to the upper surface of the board | substrate 9 efficiently. In addition, by making the positions of the main scanning direction and the sub scanning direction of the three nozzles 31 different from each other, the organic EL liquid can be applied at narrow intervals without extremely minimizing each nozzle 31 itself.

FIG. 3: is a figure which shows the structure of one of the three nozzles 31 contained in the nozzle part 30, and the liquid feeding system 80 connected to the said nozzle 31. As shown in FIG. As shown in FIG. 3, the nozzle 31 has the nozzle body 31a and the discharge hole 31b which is minute (for example, the hole diameter is 10 micrometers or more and 70 micrometers or less) formed in the lower end part of the nozzle body 31a. Have Moreover, the liquid feeding path (not shown) connected to the discharge hole 31b and the main piping 81 mentioned later is formed in the nozzle 31. As shown in FIG.

One main pipe 81 is connected to the nozzle 31. The main pipe 81 is connected to the organic EL liquid supply pipe 83 and the main solvent supply pipe 84 through the T-shaped mixing portion 82. The organic EL liquid supply source 85 which supplies the organic EL liquid which mixed the organic EL material and the solvent in the predetermined ratio is connected to the edge part of the upstream side of the organic EL liquid supply piping 83. Moreover, the mass flow controller 83a and the on-off valve 83b are interposed in the middle of the path | route of the organic EL liquid supply piping 83. FIG. On the other hand, the main solvent supply source 86 for supplying the main solvent which is one of the solvent components of the organic EL liquid is connected to the upstream end of the main solvent supply pipe 84. Moreover, the mass flow controller 84a and the on-off valve 84b are interposed in the middle of the path | route of the main solvent supply piping 84. FIG. As the main solvent supplied from the main solvent source 86, for example, mesitylene, anisole and the like having high volatility at room temperature can be used.

In such a liquid feeding system 80, when the opening / closing valve 83b is opened, the organic EL liquid supply source 85 is transferred from the organic EL liquid supply source 85 to the main pipe 81 through the organic EL liquid supply pipe 83 and the mixing unit 82. EL liquid is supplied. In addition, when the mass flow controller 83a is controlled while opening / closing the valve 83b, the supply amount per unit time of the organic EL liquid supplied from the organic EL liquid supply source 85 to the main pipe 81 is controlled.

On the other hand, in the liquid feeding system 80, when the on-off valve 84b is opened, the main solvent supply source 86 from the main solvent supply source 86 to the main pipe 81 through the main solvent supply pipe 84 and the mixing unit 82, Main solvent is supplied. Moreover, when the mass flow controller 84a is controlled while opening and closing the valve 84b, the supply amount per unit time of the main solvent supplied from the main solvent supply source 86 to the main piping 81 will be controlled.

That is, the liquid feeding system 80 of this embodiment has a supply system for supplying an organic EL liquid to the main piping 81, and a supply system for supplying a main solvent to the main piping 81, and it opens and closes the valve 83b. And 84b), the organic EL liquid and the main solvent can be selectively or simultaneously supplied from these supply systems to the main pipe 81. Moreover, the liquid feeding system 80 of this embodiment controls the mass flow controllers 83a and 84a with the opening / closing valves 83b and 84b open together, and adjusts the ratio of organic EL liquid and main solvent, These mixed liquids can be supplied to the main piping 81.

The organic EL liquid, the main solvent, or a mixed liquid thereof supplied to the main pipe 81 is introduced into the liquid supply passage inside the nozzle 31 from the main pipe 81, and the discharge hole 31b at the lower end of the nozzle 31 is provided. Is discharged downward from the bottom. When the discharge of the organic EL liquid is started by the discharge start operation described later, the organic EL liquid discharged from the discharge hole 31b of the nozzle 31 forms the liquid column L under the nozzle 31. In addition, although one nozzle 31 and the liquid feeding system 80 were demonstrated in FIG. 3, the same liquid feeding system 80 is connected also to the other nozzle 31 contained in the nozzle part 30. As shown in FIG.

Returning to FIG. 1 and FIG. 2, the description of the coating device 1 is continued.

The nozzle movement mechanism 40 is a mechanism for moving the nozzle part 30 in the main scanning direction. As shown in FIG. 1, the nozzle movement mechanism 40 has the support part 41 for supporting the nozzle part 30, and the moving part 42 for moving the support part 41 to a main scanning direction. The moving part 42 is comprised by the mechanism which combined the motor and the ball screw, for example, or the mechanism which used the linear motor. The nozzle moving mechanism 40 is located between an upper position of the standby pod 50 and an arbitrary position between the upper position of the recovery tray 60 disposed on the + X side of the stage 10. Can be moved in the main scanning direction.

The atmospheric pod 50 is a site | part for waiting the nozzle part 30 in the side of the -X side of the stage 10. As shown in FIG. On the atmospheric pod 50, three opening parts 51 for accommodating the lower end part of each nozzle 31 of the nozzle part 30 are formed. When waiting for the nozzle part 30, the nozzle part 30 is placed in the upper position of the atmospheric pod 50, the atmospheric pod 50 is raised, etc., and the lower end part of each nozzle 31 is opened in each opening part ( 51). Inside the atmospheric pod 50, a recovery mechanism for recovering the organic EL liquid, the main solvent, or a mixed liquid thereof discharged from each nozzle 31 at the time of waiting is provided.

The recovery tray 60 is a container for recovering the organic EL liquid discharged from the nozzle unit 30 on the side of the + X side and the -X side of the stage 10. The recovery tray 60 is below the movement path of the nozzle unit 30 on the -X side of the stage 10 (between the stage 10 and the standby pod 50) and the + X side of the stage 10. It is arrange | positioned at the position to become. Moreover, the collection tray 60 is arrange | positioned so that it may partially overlap with said mask plates 11 and 12 with respect to the main scanning direction. For this reason, the organic EL liquid discharged | emitted from the nozzle part 30 by the side of the stage 10 is collect | recovered continuously by the mask plates 11 and 12 and the collection tray 60. As shown in FIG.

The control part 70 is a processing part for operation control of each part in the coating device 1. 4 is a block diagram showing a connection configuration between the control unit 70 and the respective portions in the coating device 1. As shown in FIG. 4, the control unit 70 includes the stage movement mechanism 20, the nozzle movement mechanism 40, the atmospheric pod 50, the mass flow controllers 83a and 84a, and the opening / closing valve 83b. And 84b), and control their operation. The control part 70 is comprised by the computer which has a CPU and a memory, for example, and performs operation control of each said part by operating a computer according to the program installed in the computer, and operation input from a user.

<2. Operation of Coating Device>

<2-1. Operation at the start of discharge>

Next, the operation | movement at the time of starting discharge of organic EL liquid in the said coating apparatus 1 is demonstrated, referring the flowchart of FIG. 5 and the graph of FIG. In the graph of Fig. 6, the broken line indicates the flow rate of the organic EL liquid supplied from the organic EL liquid supply source 85 to the main pipe 81 through the organic EL liquid piping 83, The line shows the flow rate of the main solvent supplied from the main solvent supply source 86 to the main piping 81 through the main solvent supply piping 84. In addition, the operation | movement demonstrated below makes each nozzle 31 of the nozzle part 30 open | release the each opening part of the atmospheric pod 50, when starting discharge of organic EL liquid, such as after starting of the coating apparatus 1, etc. The operation is performed for each nozzle 31 in the state accommodated in 51). In the following discharge start operations, the mass flow controllers 83a and 84a and the on-off valves 83b and 84b operate according to the instructions from the control unit 70 described above.

When discharging the organic EL liquid in the coating device 1, first, the on-off valve 84b is opened in a state where the on-off valve 83b is closed. As a result, the main solvent is supplied from the main solvent supply source 86 to the nozzle 31 through the main solvent supply pipe 84, the mixing unit 82, and the main pipe 81, and the nozzle 31 is discharged. The main solvent is discharged downward from the hole 31b (Fig. 5: Step S1, Fig. 6: Times t1 to t2). At this time, the mass flow controller 84a is previously set to a predetermined opening degree, and the main solvent of the flow rate Fa according to the opening degree is supplied.

Since the main solvent supplied from the main solvent supply source 86 does not contain an organic EL material, it is low in viscosity as a liquid. For this reason, the main solvent is discharged smoothly from the discharge hole 31b of the nozzle 31, and forms the liquid column L below the nozzle 31. FIG. In addition, by the discharge of the main solvent, foreign substances or bubbles remaining in the discharge hole 31b or the liquid supply path inside the nozzle 31 are discharged to the outside of the nozzle 31 together with the main solvent, thereby becoming discharge resistance. These substances are excluded.

Next, the coating device 1 opens and closes the valve 83b in a state where the set flow rate of the mass flow controller 83a is minimized. Then, while gradually lowering the set flow rate of the mass flow controller 84a and gradually increasing the set flow rate of the mass flow controller 83a, the ratio of the organic EL liquid in the mixed liquid supplied to the main pipe 81 is gradually increased. . That is, while the amount of the main solvent supplied from the main solvent source 86 gradually decreases, the amount of the organic EL liquid supplied from the organic EL liquid supply source 85 gradually increases (Fig. 5: Step S2, Fig. 6: Time t2-t3). As a result, the concentration of the organic EL material in the mixed liquid discharged from the nozzle 31 gradually increases, and the viscosity of the mixed liquid also gradually increases.

In step S2 of the present embodiment, the amount of decrease in the flow rate of the main solvent supplied from the main solvent supply source 86 and the amount of increase in the flow rate of the organic EL liquid supplied from the organic EL liquid supply source 85 are always the same. The mass flow controllers 83a and 84a are controlled so that the total flow rate is always maintained at Fa. For this reason, the flow rate of the main solvent supplied from the main solvent supply source 86, and the flow rate of the organic EL liquid supplied from the organic EL liquid supply source 85 become Fa / 2 at time t3. In this way, by maintaining the total flow rate of the main solvent and the organic EL liquid supplied to the main pipe 81 at a constant value Fa, the hydraulic pressure of the liquid in the main pipe 81 is kept uniform. Therefore, the organic EL material does not locally clump and precipitate in the liquid in the main pipe 81.

In addition, at the time t2-t3 of FIG. 6, although the supply amount of a main solvent and the supply amount of an organic EL liquid are changed continuously (that is, although the set flow volume of the mass flow controllers 83a and 84a is continuously changed), The supply amount of the main solvent and the supply amount of the organic EL liquid may be changed in stages, respectively.

At time t3, when the flow rate of the main solvent supplied from the main solvent supply source 86 and the flow rate of the organic EL liquid supplied from the organic EL liquid supply source 85 become Fa / 2, the coating device 1 opens and closes. The valve 84b is closed to stop the supply of the main solvent, and the set flow rate of the mass flow controller 83a is increased to Fa at once (Fig. 5: Step S3, Fig. 6: Time t3). As a result, only the organic EL liquid of the flow rate Fa supplied from the organic EL liquid supply source 85 enters the state flowing in the main pipe 81.

In step S3 of the present embodiment, when the flow rate of the main solvent supplied from the main solvent supply source 86 and the flow rate of the organic EL solution supplied from the organic EL liquid supply source 85 are substantially the same, In addition to stopping the supply, the flow rate of the organic EL liquid is increased at once. This is because when the hydraulic pressure on the main solvent side becomes smaller than the hydraulic pressure on the organic EL liquid side in a state where both the shutoff valves 83b and 84b are opened, the organic EL liquid supplied from the organic EL liquid piping 83 is the main solvent piping 84. This is to prevent entry of such an organic EL liquid because it may enter into the inside).

In addition, in step S3 of this embodiment, stopping supply of a main solvent and increasing the flow volume of organic electroluminescent liquid to Fa maintains the oil_pressure | hydraulic of the liquid supplied to the main piping 81 uniformly, and organic electroluminescent material This is to prevent the precipitation.

Thereafter, the coating device 1 gently decreases the set flow rate of the mass flow controller 83a from Fa to the final target value Fb (FIG. 5: step S4, FIG. 6: time t4 to t5). For example, suppose that a time of about 5 minutes is spent in step S2 (t2 to t3). In this step S4 (t4 to t5), the flow rate of the organic EL liquid is spent for about 10 minutes that is doubled. Lowers. By decreasing the flow rate of the organic EL liquid in this manner, it is possible to prevent sudden fluctuations in the hydraulic pressure in the main pipe 81.

By the above operation, the organic EL liquid is discharged while forming the liquid column L having a good shape from the discharge hole 31b of the nozzle 31.

Thus, the coating device 1 of this embodiment first discharges only the main solvent from the nozzle 31, and after that, gradually increases the ratio of the organic EL liquid and gradually decreases the ratio of the main solvent, Finally, only the organic EL liquid is discharged from the nozzle 31. For this reason, the foreign substance and the bubble which remain in the inside of the nozzle 31 can be discharged to the exterior of the nozzle 31 with a main solvent, and then the organic EL liquid can be discharged. Therefore, the discharge of the organic EL liquid can be started satisfactorily from the nozzle 31. In addition, since the discharge of the organic EL liquid can be started without repeating the cleaning of the nozzle 31 and the discharge of the organic EL liquid, the discharge of the organic EL liquid can be promptly started without increasing the consumption amount of the organic EL liquid. Can be.

In particular, the coating apparatus 1 of this embodiment does not change and connect the piping connected to the nozzle 31, and supplies and discharges the main solvent to the nozzle 31 by opening / closing the opening-closing valves 83b and 84b. The supply of EL liquid is switched. For this reason, it is possible to prevent new foreign matter or bubbles from mixing inside the nozzle 31.

Moreover, the coating device 1 of this embodiment gradually lowers the supply amount of the main solvent from the main solvent supply source 86, and gradually increases the supply amount of the organic EL liquid from the organic EL liquid supply source 85, thereby providing a nozzle. The liquid discharged from (31) is gradually replaced with the organic EL liquid from the main solvent. For this reason, generation | occurrence | production of what is called a "solvent shock" in which the shape of the discharge liquid column L collapses by the sudden change of the density | concentration of a liquid discharged from a nozzle, can be prevented. Moreover, since the density | concentration of organic electroluminescent material is changed gently, even if an organic electroluminescent material is comprised by a low molecular weight compound, the problem of gelatinization of the organic electroluminescent liquid by a sudden change of a density | concentration does not arise.

<2-2. Coating Process Operation>

Next, the operation | movement at the time of apply | coating an organic EL liquid to the upper surface of the board | substrate 9 in said coating apparatus 1 is demonstrated, referring the flowchart of FIG. In addition, at the time when the application | coating process demonstrated below is started, the discharge start operation | movement of the organic EL liquid demonstrated in said 2-1. Is already completed, and each of the nozzle part 30 in the atmospheric pod 50 is carried out. Organic EL liquid is favorably discharged from the nozzle 31 in a liquid columnar shape.

When performing the application | coating process of the board | substrate 9 in this coating device 1, the board | substrate 9 is first placed on the upper surface of the stage 10 (step S5). The substrate 9 is placed on the stage 10 so that the plurality of grooves 9a formed on the upper surface thereof face the main scanning direction. Moreover, the stage movement mechanism 20 moves the stage 10 so that the 3 groove | channel 9a of the most + Y side on the board | substrate 9 may be located under the scanning area of the nozzle part 30, and the board | substrate ( 9) Adjust the position.

Next, the coating device 1 detaches the atmospheric pod 50 from the nozzle 31 by lowering the atmospheric pod 50 or the like, and further operates the nozzle moving mechanism 40 to operate the nozzle portion ( Move 30) to the + X side. The nozzle unit 30 moves to the + X side while discharging the organic EL liquid from each nozzle 31, and applies the organic EL liquid onto the three grooves 9a on the most + Y side on the substrate 9. In addition, a part of the organic EL liquid discharged during the movement of the nozzle unit 30 falls to the upper surfaces of the recovery tray 60 and the mask plates 11 and 12 and is recovered.

When the nozzle part 30 moves to the upper part of the mask board 12 of the + X side, the coating device 1 next applies the width | variety of three nozzles 31 by operating the stage movement mechanism 20. FIG. The stage 10 is moved to the + Y side by minutes (that is, by three rows of the grooves 9a). Then, the nozzle part 30 is moved to the -X side while discharging the organic EL liquid from the nozzle 31. As a result, the organic EL is applied onto the next three grooves 9a on the substrate 9.

In this way, the coating device 1 repeats the application of the organic EL liquid in the main scanning direction by a predetermined number of times while shifting the substrate 9 in the sub-scanning direction by the coating width of the nozzle portion 30, and thereby the substrate 9. The organic EL liquid is applied onto all the grooves 9a on the () (step S6).

When the organic EL liquid is applied to all the grooves 9a on the substrate 9, the coating device 1 further operates the nozzle moving mechanism 40, and the nozzle unit 30 is moved to the upper position of the atmospheric pod 50. Move it. When the nozzle part 30 moves to the upper position of the atmospheric pod 50, the applicator 1 raises the atmospheric pod 50, etc., and the lower end part of each nozzle 31 of the atmospheric pod 50 is carried out. It is accommodated in each opening 51. Subsequently, the substrate 9 after the coating treatment is carried out from the stage 10 (step S7), and the coating treatment of the organic EL liquid on the one substrate 9 is completed.

<3. Modifications>

As mentioned above, although one Embodiment of this invention was described, this invention is not limited to said example. For example, in the above example, although three nozzles 31 were mounted in the nozzle part 30 of the coating device 1, the number of nozzles mounted in the nozzle part 30 may be one or two. 4 or more may be sufficient. Moreover, although the said coating apparatus 1 was equipped with the three nozzle 31 in order to discharge the organic EL liquid for red, green, and blue, the coating apparatus of this invention is a some nozzle ( 31 may be used to discharge the monochromatic organic EL liquid.

In the above example, although the mass flow controllers 83a and 84a were used to adjust the supply amounts of the organic EL liquid and the main solvent, the supply amounts of the organic EL liquid and the main solvent were adjusted using other flow rate adjusting mechanisms. You may also For example, as a replacement for the mass flow controllers 83a and 84a, a flow control valve without a flow sensor may be used.

In addition, in step S2 of the discharge start operation, although the flow rate of the main solvent was decreased linearly (with a constant rate of change), the flow rate of the organic EL liquid was increased linearly (with a constant rate of change). And the change in flow rate of the organic EL liquid may not be such a linear change (change in constant change rate). For example, as shown in Fig. 8, the flow rate of the main solvent is lowered so that the rate of change gradually decreases (so that the absolute value of the rate of change gradually increases), and the flow rate of the organic EL liquid is increased so that the rate of change gradually increases. do. In this way, a sudden change in concentration can be prevented at time t2 at which the supply of the organic EL liquid is started.

In addition, in step S1 of the above discharge start operation, the supply of the main solvent is started while the supply of the organic EL liquid is stopped, but a small amount of the organic EL liquid may be supplied from the beginning. That is, first, the mixed liquid containing a small amount of organic EL liquid and a large amount of main solvent is discharged from the nozzle 31, and then the ratio of the organic EL liquid is gradually increased, and the ratio of the main solvent is gradually lowered, Finally, only the organic EL liquid may be discharged from the nozzle 31.

Moreover, although the said coating apparatus 1 apply | coated the organic EL liquid containing the organic electroluminescent material as a to-be-coated material to the upper surface of the board | substrate 9, the coating apparatus of this invention is an antireflection film material and a photoresist. The coating liquid containing other to-be-coated material, such as a material, may be apply | coated to the upper surface of the board | substrate 9. Moreover, the coating apparatus of this invention may apply | coat the coating liquid which mixed the aqueous to-be-coated material and aqueous solvent to the upper surface of the board | substrate 9. Moreover, although the said coating device 1 made the glass substrate 9 for organic electroluminescent display objects into a process object, the coating device of this invention is a glass substrate for liquid crystal display devices, the glass substrate for PDPs, a semiconductor wafer, Another substrate, such as a glass / ceramic substrate for magnetic / optical disks, may be used as the processing target.

1 is a top view of a coating device according to an embodiment of the present invention.

FIG. 2 is a longitudinal cross-sectional view of the coating device taken along the line II-I of FIG. 1. FIG.

3 is a diagram illustrating a configuration of a nozzle and a liquid feeding system.

4 is a block diagram showing a connection configuration of each part and a control unit in the coating apparatus.

Fig. 5 is a flowchart showing the flow of the operation when starting to discharge the organic EL liquid.

6 is a graph showing variations in the supply amounts of the organic EL liquid and the main solvent.

Fig. 7 is a flowchart showing the flow of operation when applying the organic EL liquid on the upper surface of the substrate.

8 is a graph showing variations in the supply amounts of the organic EL liquid and the main solvent according to the modification.

[Description of the code]

1: coating device 9: substrate

20: stage moving mechanism 30: nozzle unit

31 nozzle 31b discharge hole

40: nozzle moving mechanism 50: atmospheric pod

51 opening 60: recovery tray

70 control unit 80 liquid feed meter

81: main pipe 82: mixing

83: organic EL liquid supply piping 83a: mass flow controller

83b: on-off valve 84: main solvent supply piping

84a: mass flow controller 84b: on-off valve

85: organic EL liquid supply source 86: main solvent supply source

L: Liquid wine

Claims (7)

In the coating apparatus which apply | coats the coating liquid containing a to-be-coated material and a predetermined organic solvent to the surface of a board | substrate, A nozzle for discharging the coating liquid in a liquid column toward the surface of the substrate through a discharge hole having a diameter of 70 μm or less , A pipe portion connected to the nozzle, Coating liquid supplying means for supplying the coating liquid to the pipe portion; Solvent supply means for supplying the organic solvent to the pipe portion; Control means for controlling the coating liquid supply means and the solvent supply means, The control means, A solvent supply operation for supplying the organic solvent from the solvent supply means in a state in which supply of the coating liquid from the coating liquid supply means is stopped; After the solvent supply operation, the supply amount of the coating liquid from the coating liquid supply means is gradually reduced while the supply amount of the organic solvent from the solvent supply means is maintained while maintaining the shape of the liquid column formed below the nozzle. A substitution operation that gradually increases Coating liquid supply operation | movement which supplies the said coating liquid from the said coating liquid supply means after the said substitution operation. Kigo when running, The control means, in the substitution operation, makes the amount of decrease of the supply amount of the organic solvent from the solvent supply means equal to the amount of increase of the supply amount of the coating liquid from the coating liquid supply means, and the organic solvent and the An application apparatus, characterized in that the total flow rate of the coating liquid is kept constant . In the coating apparatus which apply | coats the coating liquid containing a to-be-coated material and a predetermined organic solvent to the surface of a board | substrate, A nozzle for discharging the coating liquid in a liquid column toward the surface of the substrate through a discharge hole having a diameter of 70 μm or less, A pipe portion connected to the nozzle, Coating liquid supplying means for supplying the coating liquid to the pipe portion; Solvent supply means for supplying the organic solvent to the pipe portion; Control means for controlling the coating liquid supply means and the solvent supply means, The control means, A solvent supply operation for supplying the organic solvent from the solvent supply means in a state in which supply of the coating liquid from the coating liquid supply means is stopped; After the solvent supply operation, the supply amount of the coating liquid from the coating liquid supply means is gradually reduced while gradually lowering the supply amount of the organic solvent from the solvent supply means and preventing the occurrence of solvent shock. The substitution operation to increase, Coating liquid supply operation | movement which supplies the said coating liquid from the said coating liquid supply means after the said substitution operation. Run it, The control means, in the substitution operation, equalizes the decrease amount of the supply amount of the organic solvent from the solvent supply means with the increase amount of the supply amount of the coating liquid from the coating liquid supply means, and the organic solvent and the coating. An application device characterized in that the total flow rate of the liquid is kept constant . The method according to claim 1 or 2, The control means, In the substitution operation, the supply of the organic solvent from the organic solvent supply means when the supply amount of the organic solvent from the solvent supply means is substantially equal to the supply amount of the coating liquid from the coating liquid supply means. An application device, characterized in that for stopping the. The method according to claim 3, The said coating liquid supply means has a coating liquid mass flow controller provided on the coating liquid piping and the said coating liquid piping, The said solvent supply means has a solvent piping and the solvent mass flow controller provided on the said solvent piping, The said control means performs the said substitution operation | movement by controlling the said mass flow controller for coating liquids and the said mass flow controller for solvents, The coating apparatus characterized by the above-mentioned. The method according to claim 4 , The said coating liquid contains an organic EL material as said to-be-coated substance, The coating apparatus characterized by the above-mentioned. In the coating apparatus which apply | coats the coating liquid containing a to-be-coated material and a predetermined organic solvent to the surface of a board | substrate, A nozzle for discharging the coating liquid in a liquid column toward the surface of the substrate through a discharge hole having a diameter of 70 μm or less , A pipe portion connected to the nozzle, Coating liquid supplying means for supplying the coating liquid to the pipe portion; Solvent supply means for supplying the organic solvent to the pipe portion; Control means for controlling the coating liquid supply means and the solvent supply means, The control means, A mixed liquid supply operation for supplying a small amount of the coating liquid from the coating liquid supplying means and supplying the organic solvent from the solvent supplying means; After the mixed liquid supply operation, the supply amount of the coating liquid from the coating liquid supply means is gradually reduced while the supply amount of the organic solvent from the solvent supply means is maintained while maintaining the shape of the liquid column formed below the nozzle. A substitution operation that gradually increases Coating liquid supply operation | movement which supplies the said coating liquid from the said coating liquid supply means after the said substitution operation. And running, The control means, in the substitution operation, equalizes the decrease amount of the supply amount of the organic solvent from the solvent supply means with the increase amount of the supply amount of the coating liquid from the coating liquid supply means, and the organic solvent and the coating. An application apparatus, characterized in that the total flow rate of the liquid is kept constant . In the coating apparatus which apply | coats the coating liquid containing a to-be-coated material and a predetermined organic solvent to the surface of a board | substrate, A nozzle for discharging the coating liquid in a liquid column toward the surface of the substrate through a discharge hole having a diameter of 70 μm or less, A pipe portion connected to the nozzle, Coating liquid supplying means for supplying the coating liquid to the pipe portion; Solvent supply means for supplying the organic solvent to the pipe portion; Control means for controlling the coating liquid supply means and the solvent supply means, The control means, A mixed liquid supply operation for supplying a small amount of the coating liquid from the coating liquid supplying means and supplying the organic solvent from the solvent supplying means; After the mixed liquid supply operation, the supply amount of the coating liquid from the coating liquid supply means is gradually decreased while gradually lowering the supply amount of the organic solvent from the solvent supply means and preventing the occurrence of solvent shock. The substitution operation to increase, Coating liquid supply operation | movement which supplies the said coating liquid from the said coating liquid supply means after the said substitution operation. Run it, The control means, in the substitution operation, equalizes the decrease amount of the supply amount of the organic solvent from the solvent supply means with the increase amount of the supply amount of the coating liquid from the coating liquid supply means, and the organic solvent and the coating. An application device characterized in that the total flow rate of the liquid is kept constant .

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