TW201636115A - Coating apparatus and coating method - Google Patents

Abstract

To conduct a condensation-free mixture of two kinds of liquids that easily condense during mixture and to smear the mixed liquid onto a substrate to form a film. A coating device 1 includes a pipe 7a that supplies a coating liquid a; a pipe 7b that supplies a coating liquid b; a mixing device 4 that mixes the coating liquid a from the pipe 7a and the coating liquid b from the pipe 7b; a filtering device 5 that filters the mixed coating liquid c produced by the mixing device 4; and a connecting pipe 3 that has slits, through which the mixed and filtered coating liquid c is sprayed. The coating liquid c is sprayed through the slits onto a substrate W to form a film on the substrate.

Description

Coating device and coating method

The present invention relates to a coating apparatus for applying a coating liquid from a slit formed in a ferrule to apply a coating liquid to a substrate, and more particularly to a coating liquid for mixing and coating two types of coating liquid. Coating device.

A display device including a liquid crystal panel, an organic EL (electroluminescence) panel, and a touch panel used in combination with the above is formed with a plurality of thin films on a substrate on which a display function is formed in a manufacturing process. One of the main means for forming these thin films is a photolithography method in which a coating liquid containing a film forming component is applied onto a substrate such as a glass substrate or a film, and dried, exposed, and developed. As a coating apparatus for coating a coating liquid for forming a film, there is known a coating apparatus called a slit nozzle coater, which is provided with a ferrule for forming a slit for ejecting a coating liquid ( Refer to, for example, Patent Document 1). The coating apparatus includes a tank, a storage coating liquid, and a pump for supplying the coating liquid in the tank to the slit of the ferrule.

The slit of the ferrule is formed to be elongated along the width direction of the substrate, and for example, the coating liquid can be ejected from the slit by horizontally moving the ferrule with respect to the substrate placed on the stage. A film (coating film) of the coating liquid is formed on the surface of the substrate.

Although it is possible to form various thin films by using the coating device, when a certain conductive film is in contact with air at room temperature, a solidified/dried liquid is immediately generated, and a countermeasure against liquid supply piping is required, and for example, a countermeasure against air leakage is required.

However, in the case where the coating liquid for forming a conductive film is a two-liquid mixing type, solidification may start immediately after mixing. In this case, the countermeasure for improving the airtightness of the piping is completely meaningless, and a new countermeasure is required, that is, a countermeasure for mixing the two liquids immediately before the application is required.

However, the behavior of mixing the two liquids just prior to coating requires that the agitating portion be placed near the ferrule having the slit. This means that the two liquids are sufficiently mixed and the mixing time is reduced, and there is a possibility that the mixing and mixing are insufficient. On the other hand, in the case of using a stirring tank which can ensure sufficient mixing time, even if the stirring tank is provided in the vicinity of the ferrule, for example, since the stirring time becomes long, the possibility of starting solidification becomes high.

Therefore, it is desirable to provide a coating apparatus having a stirring device corresponding to a two-liquid mixing type coating liquid, and even if the stirring portion is provided in the sleeve The stirring and mixing of the two liquids can also be sufficiently performed.

[Previous Technical Literature]

[Patent Literature]

Patent Document 1: Japanese Laid-Open Patent Publication No. 2000-157906.

An object of the present invention is to provide a coating apparatus which is capable of stable solidification without causing solidification even in the case of using a two-liquid mixing type coating liquid, particularly in the case of using a coating liquid which rapidly solidifies after mixing.

In the coating apparatus of the present invention, the coating liquid supplied from the coating liquid supply means is applied to the surface of the sheet-like substrate by a sleeve having a slit-like discharge port, and a film is formed on the substrate; the coating apparatus is provided with a mixing device for mixing and stirring a coating liquid composed of two kinds of different liquids supplied by the coating liquid supply means; a filtering device for filtering the mixed coating liquid supplied from the mixing device; and a coating liquid supply pump; The mixed coating liquid filtered through the filtering device is supplied to the ferrule.

According to the coating apparatus of the present invention, even if a coating liquid composed of two kinds of different liquids is mixed and stirred before coating, the coating is applied. The mixture can be mixed and stirred immediately before coating, and then supplied to the pump through a filtration device and a coating liquid, and the substrate is coated by a sleeve having a slit. Further, the coating liquid supply device of the present invention is characterized in that it includes a liquid supply means and an individual storage device and a pipe for two different types of liquids, and the two types of different liquid pipes are individually joined to the mixing device. And feeding the two different kinds of liquids at the same time to the aforementioned mixing device.

According to this configuration, it is not necessary to mix two kinds of different liquids beforehand, and it is possible to simultaneously supply liquid to the mixing device.

Further, the mixing device of the present invention is characterized in that it is provided with a screw having at least one thread direction different and having an outer shape and a pitch equal to each other; each screw system has a cylindrical outer tube portion and is external to the screw The partial cross-section of the diameter is arranged; in the intersecting portion, the liquid is supplied to the filtering device while mixing and stirring the two different types of liquid.

By providing the mixing device as described above, it is possible to efficiently feed the coating liquid composed of two kinds of different liquids while mixing and stirring.

Further, a mixing apparatus according to another embodiment of the present invention is characterized in that it is provided with a screw having at least one different thread direction and an outer shape and a pitch: each screw is rotatably driven in a different rotation direction, and is mixed while being mixed. The above two types of different liquids are stirred while being supplied to the aforementioned filtering device.

By rotating the screw of the mixing device as described above, even when the viscosity of the two kinds of different liquids to be mixed is high, the liquid can be efficiently supplied to the next device while mixing and stirring the liquid.

Further, the coating method of the present invention mixes and agitates two kinds of different liquids supplied from different storage devices via different supply paths by a mixing device having a stirring mechanism therein, and is filtered by the filtering device and mixed through the mixing device. After the mixed coating liquid formed by stirring, the liquid is supplied to the coating device by a liquid supply pump, and the mixed coating liquid is applied to the sheet-like substrate by a sleeve having a slit in the coating device.

According to the coating method of the present invention, even in the case of coating a mixed coating liquid formed by mixing and stirring two kinds of different liquids, mixing and stirring of the above two kinds of different liquids can be efficiently performed, and by filtering Further, the apparatus further filters the formed mixed coating liquid and supplies it to a coating device, and applies it to a sheet-like substrate via a sleeve of the coating device, thereby removing bubbles or foreign matter which may be formed during mixing, thereby enabling high quality. The coating film is formed on the sheet-like substrate.

According to the coating apparatus and the coating method of the present invention, even when a mixed coating liquid formed by mixing and stirring two kinds of different liquids is applied to a substrate, two kinds of different liquids can be effectively mixed and stirred, and It can remove bubbles or foreign matter that may form during mixing and stirring, so A high quality coating film can be formed on the substrate.

1‧‧‧ Coating device

2‧‧‧Workbench

3‧‧‧ Sockets

4‧‧‧Mixed device

5‧‧‧Filter device

6‧‧‧Control device

7, 7a, 7b, 7c‧‧‧ piping

8‧‧‧ pump

9a, 9b‧‧‧ slots

41, 47‧‧‧ Screw Department

41a, 41b, 47a, 47b‧‧‧ screw

42‧‧‧Liquid entrance block

43a, 43b‧‧‧ liquid inlet

44‧‧‧Outer tube

45‧‧‧Liquid Export Department

46‧‧‧Liquid exports

48‧‧‧ drive shaft

49‧‧‧ Cover

81‧‧‧ cylinder

82‧‧‧Piston

83‧‧‧ rolling diaphragm

84‧‧‧Upper casing

84a‧‧Inhalation

84b‧‧‧Spray outlet

85‧‧‧Decompression exhaust

a, b, c‧‧‧ coating liquid

W‧‧‧Substrate

X, Y, Z‧‧ Direction

Fig. 1 is a schematic view showing an embodiment of a coating apparatus of the present invention.

Fig. 2 is a schematic cross-sectional view for explaining the structure of the mixing device in the present invention.

Fig. 3 is a schematic cross-sectional view for explaining the structure of a mixing device in another embodiment of the present invention.

Fig. 4 is a schematic cross-sectional view showing a coating liquid supply pump used in the coating device of the present invention.

Fig. 5 is a schematic structural view showing an application example of the coating apparatus of the present invention.

Hereinafter, embodiments of the present invention will be described based on the drawings.

Fig. 1 is a schematic view showing an embodiment of a coating apparatus of the present invention. The coating apparatus 1 includes a table 2 on which a sheet-shaped substrate W such as glass is placed, and a sheet-like substrate W is fixed by vacuum suction or the like; the sleeve tube 3 is formed with a slit therein; and a driving device The ferrule 3 is horizontally moved (X-direction movement) and vertical movement (Z-direction movement) independently and freely with respect to the substrate W on the table 2. Further, the coating device 1 further includes a liquid supply means as a liquid supply means, and the liquid supply means is constituted by a member for accommodating the coating liquid a and a groove 9a for The tank 9b for storing the coating liquid b; the piping 7a and the piping 7b (including the grooves 9a and 9b to the mixing device 4) are supplied with two different coating liquids a and supplied from the grooves 9a and 9b, respectively. The liquid b; the mixing device 4 performs mixing and stirring of the coating liquid a and the coating liquid b to form a mixed coating liquid c; and the piping 7c (which is a pipe 7c until the ferrule 3) is supplied from the mixing device 4 The coating liquid c is mixed; the filtration device 5 filters the mixed coating liquid c supplied from the mixing device 4; and the pump 8 supplies the mixed coating liquid c filtered by the filtration device 5 to the ferrule 3. Moreover, the piping 7 is a general term of the piping 7a to the piping 7c.

In the present embodiment, the liquid supply means from the tank 9a and the groove 9b to the mixing device 4 is not limited. Therefore, it can be pressurized and pressure-fed to the groove 9a and the groove 9b, and a pump (not shown) can be provided and the liquid can be supplied via the pump. In addition, unless otherwise required, in the description of the examples, the two types of coating liquid a and the coating liquid b are mixed in a ratio of one to one.

The coating device 1 supplies the mixed coating liquid c formed by the mixing device 4 and filtered by the filtering device 5 to the ferrule 3 by the pump 8, and the ferrule 3 is vertically lowered by the driving device and is at the front end portion and the sheet shape. After the parallel gap between the substrates W is a predetermined value, the mixed coating liquid c is ejected from the slits while moving the ferrule 3 horizontally, thereby being fixed to the substrate W on the table 2 by an adsorption mechanism (not shown). A film (coating film) composed of the mixed coating liquid c is formed on the surface. Therefore, the moving direction of the ferrule 3 becomes the coating direction (X direction).

Further, the coating device 1 includes a control device 6 for controlling the operation of each member of the coating device 1, and the control device 6 performs the movement of the ferrule 3, the driving of the pump 8, the detailed control of the coating operation, and the coating. The loading/unloading of the substrate W of the apparatus 1 is controlled by an operation.

Fig. 2 is a schematic cross-sectional view showing a mixing device in the coating device of the present invention. The mixing device 4 is composed of a screw portion 41, a liquid inlet block 42, a liquid inlet 43a and a liquid inlet 43b, a liquid outlet portion 45, and a liquid outlet 46, to which the pipes 7a and the pipes 7b are respectively connected. Further, the inside of the screw portion 41 is composed of a screw 41a having a different thread direction, a screw 41b, and an outer tubular portion 44. In the present embodiment, although the outer diameters of the screw 41a and the screw 41b are set to be equal, the diameters of the two components of the mixed coating liquid c may be set to different diameters. Further, the screw pitch of the screw 41a and the screw 41b can be arbitrarily set in accordance with the characteristics of the coating liquid a and the coating liquid b to be mixed. For example, in the case of a liquid which is poorly mixed and agitated, it is only necessary to perform a correspondence in which the screw pitch is set to be small or the like.

The mounting interval between the screw 41a and the screw 41b is set to a value smaller than the total value of the respective screws. Further, the screw portion 41 has a structure in which there is no portion overlapping the screw 41a and the screw 41b, and there is no wall between the two screws. Thereby, the two types of coating liquid a and the coating liquid b are supplied while being rotated and stirred along the screw, and since there is no wall between the screws, It is easy to mix the liquid to be supplied while rotating. In the present embodiment, the outer tubular portion 44 is formed into a shape in which two cylinders are connected, but the ease of mixing may be considered, and other shapes may be used. For example, a circular shape may be set. In this case, since the contact area of the mixed two liquids is increased, it is easier to mix. Further, although the screw 41a and the screw 41b of the present embodiment have a shape in which the overlapping portion is cut off during the installation, the arrangement of the screw in the axial direction may be shifted, and the screw profile may be formed as a non-cutting portion. Round shape.

Here, the superiority of using two screws in the mixing device will be described in detail. In general, an example of a stirring device using a screw is a mixing nozzle for a resin injection molding injection molding machine. Here, an important difference between the mixing nozzle of the injection molding machine and the mixing device of the present invention is that a solid such as a powder or a bead is introduced into the mixing nozzle, and is supplied to the mixing device of the present invention. Two different types of liquids. On the other hand, from the functional side, the mixing nozzle is heated and melted by the internal resin material and is ejected to the mold, whereas the mixing device of the present invention mixes and agitates only two kinds of different liquids. The material of the mixing nozzle is one type and it is only required to be uniformly melted during transportation. In contrast, the mixing device of the present invention needs to appropriately mix and stir both types of liquid.

Here, the mixing nozzle of the injection molding machine has substantially only one screw, and the configuration has the aforementioned object, that is, has a sufficient melting of the resin material. The function of the solution. However, in the case where two liquids are supplied by one screw, there is a high possibility that the initial mixed state is maintained and the liquid is supplied in a state where mixing and stirring are insufficient. To prevent this problem, both types of liquids need to be thoroughly mixed and stirred. The screw arrangement of the mixing device of the present invention does not require a structure for separating two types of liquids which are fed by the rotation of the screw, and therefore can be continuously mixed and stirred by centrifugal force diffusion.

Next, the function of the mixing device 4 will be described. The liquid inlet block 42 of the mixing device 4 is provided with a liquid inlet 43a and a liquid inlet 43b, and is respectively coupled via a pipe to a tank 9a for storing the coating liquid a and a tank 9b for storing the coating liquid b. Thereby, the coating liquid a and the coating liquid b are prevented from being mixed with each other before being mixed by the mixing device 4. Then, the coating liquid a and the coating liquid b are conveyed to the screw portion 41, and are fed by the screw 41a and the screw 41b, and are mixed and stirred to form a mixed coating liquid c. Finally, the mixed coating liquid c is sent to the liquid outlet portion 45, and is supplied from the liquid outlet 46 to the filtration device 5 via the pipe 7c.

Here, in the embodiment, although the liquid inlet 43a and the liquid inlet 43b are inclined with respect to the screw axis, they may be arranged in parallel. Further, in the embodiment, although the liquid outlet 46 is formed in a shape different in size from the inlet and the outlet, the inlet and the outlet may have a parallel shape. Further, the cross section of the liquid outlet 46 may be, for example, an ellipse, an ellipse, a rectangle, or the like, as long as it is a shape that does not cause uneven discharge, and can be used in combination with the characteristics of the coating liquid. use.

Fig. 3 is a schematic cross-sectional view showing another embodiment of the mixing device of the present invention. The mixing device 4 of the present embodiment is composed of a screw portion 47, a liquid inlet block 42, and a liquid inlet 43a and a liquid inlet 43b, a liquid outlet portion 45, and a liquid outlet 46 to which the pipes 7a and the pipes 7b are respectively connected. Further, the inside of the screw portion 47 is composed of a circular screw 47a having a different thread direction, a circular screw 47b, a drive shaft 48, and a cover 49. The screw 47a and the screw 47b of the present embodiment are rotatably coupled to a driving device (not shown). Further, in the present embodiment, although the outer diameters of the screw 47a and the screw 47b are set to be equal, the diameters of the two components of the mixed coating liquid c may be set to different diameters. Further, the screw pitch of the screw 47a and the screw 47b can be arbitrarily set in accordance with the characteristics of the mixed liquid. For example, in the case of a liquid which is poorly mixed and agitated, it is only necessary to perform a correspondence in which the screw pitch is set to be small or the like.

Since the screw 47a and the screw 47b of the present embodiment are coupled to a driving device (not shown), the screw 47a and the screw 47b are rotated in the present embodiment, whereby the mixing device 4 can have a liquid feeding driving force. Thereby, it is possible to correspond to a wide range of liquids as compared with the case of relying on the liquid supply force other than the mixing device 4. In other words, in the case of using a high-viscosity liquid, not only the liquid can be more efficiently mixed and stirred by the conveying force of the screw 47a and the screw 47b, but also the liquid supply can be performed more reliably. Further, in the case of using a liquid having high coagulation property, in order to rapidly supply liquid to the ferrule, it is also possible to increase the feed rate by setting the number of rotation of the screw.

The mounting interval between the screw 47a and the screw 47b is set to a value larger than the total value of the respective screws. This is because the screw is required to interfere with each other in order to prevent the screw 47a and the screw 47b from rotating in the present embodiment. Of course, in the case of a configuration that does not interfere, for example, in the case where the screw 47a and the screw 47b are formed at the same pitch and the arrangement is shifted by a half pitch, the mounting interval may be set to be larger than the radius of each screw. The value is still small.

As in the example of Fig. 2, in the embodiment, the liquid inlet 43a and the liquid inlet 43b may be either inclined or arranged in parallel with respect to the screw axis. Further, in the embodiment, although the liquid inlet 43a and the liquid inlet 43b are provided on the center side of the mixing device 4, they may be disposed outside the screw 47a and the screw 47b. However, regardless of the configuration, it is necessary to make a configuration that does not interfere with the drive shaft 48, the liquid inlet 43a and the liquid inlet 43b, and the liquid outlet 46. Further, although the liquid outlet 46 has a shape in which the inlet and the outlet are different in size as in the embodiment of Fig. 2, the inlet and the outlet may have a parallel shape. Further, the cross section of the liquid outlet 46 may be, for example, an ellipse, an ellipse, a rectangle, or the like, as long as it is a shape that does not cause uneven discharge, and can be used in combination with the characteristics of the coating liquid. use.

As shown in FIG. 1, the mixed coating liquid c formed in the mixing device 4 is sent to the filtration device 5 via the pipe 7c. The interior of the filter device 5 is not The filter member and the housing are shown. The purpose of the filter member of the filtering device 5 is to remove bubbles which may be generated by the liquid mixing and agitation process in the mixing device 4 and to generate solid foreign matter. In the case where two different types of coating liquid a and coating liquid b are mixed and stirred by the mixing device shown in FIG. 2 or FIG. 3, the liquid is caused by the local pressure unevenness caused by the mixing and stirring of the screw. The gas component contained in the gas becomes easy to separate and generates bubbles. Alternatively, the solid component of the liquid is likely to locally adhere/stack due to contact with the screw, and becomes a solid foreign matter when peeled off. The filter of the filtering device 5 can remove these bubbles or generate solid foreign matter which adversely affect the coating quality. Here, the structure and material of the filter member can be determined depending on the type of liquid to be mixed and the like. Further, the filter device 5 is provided with a deaeration mechanism (not shown), and the air bubbles captured by the filter member can be exhausted to the outside of the filter device 5 by the deaeration mechanism.

Next, the mixed coating liquid c is supplied to the pump 8 shown in Fig. 1 . In the case of application to the sheet-like substrate shown in Fig. 1, the pump 8 is preferably a syringe pump having a piston configuration as shown in the embodiment of the schematic cross-sectional view of Fig. 4 or a tube type as in other examples. A pump in the form of a fixed amount is circulated as a tubephragm pump (not shown). In the embodiment of Fig. 4, the pump 8 is composed of a cylinder 81, a piston 82, a rolling diaphragm 83 sealed to the piston 82 and sealing the piston 82 from the cylinder 81, and an upper casing. The casing 84 is configured, and the upper casing 84 is provided with a suction port 84a and a discharge port 84b. Further, a driving side of the piston in the cylinder 81 is provided to prevent wrinkles of the rolling diaphragm 83, and the like. The deformed decompression vent 85 is used to constantly apply tension to the rolling diaphragm 83 by vacuum suction.

Next, the function of the pump 8 will be described. Simultaneously with the step of providing the substrate W in the coating device 1, the piston 82 of the pump 8 is moved to a first position (not shown) that is separated from the upper casing 84 by a driving device (not shown), and the mixed coating liquid c is mixed. Attraction. At this time, the rolling diaphragm 83 is additionally moved to the piston 82. Next, when the coating is started, the piston 82 is moved to a second position (not shown) close to the upper casing 84, and a predetermined amount required for coating the substrate W is ejected. After the application is completed, the substrate W is carried out to the outside of the coating device 1 by a transport device (not shown). Repeat the above steps when the next substrate is loaded.

The mixed coating liquid c discharged from the pump 8 is sent to the ferrule 3 of the coating device 1, and is discharged to the substrate W through the slit of the ferrule 3 to form a coating film. In the above-described series of steps, the liquid supply system of the coating liquid can be controlled by a valve (not shown) which is appropriately disposed in the piping. For example, a valve is provided in front of and behind the pump 8, which prevents improper flow or inflow of the coating liquid. The form of the valve is preferably appropriately selected in accordance with the type of the coating liquid or the like. Furthermore, the above-described series of steps are controlled by the control device 6.

Although the coating apparatus of the present invention has been described based on the above embodiments, the present invention can also be applied to coating apparatuses other than the above embodiments. For example, although the coating device 1 is configured such that the ferrule 3 scans the substrate W placed on the fixed table 2, the ferrule 3 may be in a fixed position. The workbench is in a movable form. Furthermore, the substrate need not be fixed to the table, and the present invention can also be applied to a floating coating table in which the substrate floating mechanism is disposed on the table 2 and the same floating mechanism is disposed before and after the table.

Further, the present invention can be applied to a coating system using a continuous substrate as shown in the schematic configuration diagram of Fig. 5, in addition to a sheet-like substrate. In the coating system of Fig. 5, when the pump 8 is in the form of the cyclic discharge shown in Fig. 4, it is not possible to continuously eject, which is less preferable. Therefore, the pump 8 needs to be constructed as a pump that can be continuously ejected, or as a pump in the mixing device 4 as shown in FIG. However, in the case of intermittently conveying the substrate, the circulation discharge pump shown in Fig. 4 can also be used. In the mixing device 4, a pump or a dedicated pump may be used in combination, and may be appropriately selected depending on the type of the coating liquid. For example, in the case where the viscosity of the mixed coating liquid is high, it is preferable to provide a dedicated pump. Further, the form of the continuous discharge pump is preferably appropriately selected in accordance with the coating liquid.

As described above, with the coating apparatus of the present invention, even when two kinds of different liquids are mixed and applied to various substrates W, the coating can be applied without causing coagulation of the mixed solution.

1‧‧‧ Coating device

2‧‧‧Workbench

3‧‧‧ Sockets

4‧‧‧Mixed device

5‧‧‧Filter device

6‧‧‧Control device

7, 7a, 7b, 7c‧‧‧ piping

8‧‧‧ pump

9a, 9b‧‧‧ slots

a, b‧‧‧ coating liquid

W‧‧‧Substrate

X, Y, Z‧‧ Direction

Claims (5)

A coating apparatus which applies a coating liquid supplied from a coating liquid supply means to a surface of a sheet-like substrate by a sleeve having a slit-like discharge port to form a film on the substrate; the coating apparatus is provided with: The mixing device mixes and agitates a coating liquid composed of two kinds of different liquids supplied from the coating liquid supply means; the filtering device filters the mixed coating liquid supplied from the mixing device; and the coating liquid supply pump The mixed coating liquid filtered through the aforementioned filtering device is supplied to the aforementioned ferrule. The coating apparatus according to claim 1, wherein the coating liquid supply means includes a liquid supply means and an individual storage means and a pipe for the two different types of liquids, and the two types of liquids of the different types are individually selected. The ground is joined to the aforementioned mixing device, and the two different types of liquids described above are simultaneously supplied to the mixing device. The coating device according to claim 1 or 2, wherein the mixing device is provided with at least one screw having a different thread direction and an outer shape and a pitch; each screw has a cylindrical outer tubular portion and is external to the screw The partial cross-section of the diameter is arranged; in the intersecting portion, the liquid is supplied to the filtering device while mixing and stirring the two different types of liquid. The coating device according to claim 1 or 2, wherein the mixing device is provided with at least one thread having a different thread direction and an outer shape and a pitch The screw is rotatably driven in different rotation directions, and is supplied to the filtering device while mixing and stirring the two kinds of different liquids. A coating method is a method in which two kinds of different liquids supplied from different storage devices through different supply paths are mixed and stirred by a mixing device having a stirring mechanism therein, and are filtered and filtered by a filtering device to be mixed and stirred by the mixing device. After the mixed coating liquid is supplied to the coating device by a liquid supply pump, the mixed coating liquid is applied to the sheet-like substrate by a slit tube having a slit in the coating device.