JP6426491B2 - Coating apparatus and coating method - Google Patents

Description

  According to the present invention, even in the pressure supply method, it is possible to prevent the coating liquid discharged from the nozzle from being raised first when coating processing is started, and it is possible to suppress the coating processing, and the coating processing is started. The present invention relates to a coating apparatus and a coating method which can be applied to an object to be coated with an appropriate coating thickness from a point of time and which has a simple configuration and easy control of coating thickness adjustment.

  The coating liquid stored in the inside of the tank is supplied to the nozzle moved relative to the object to be coated such as a substrate by the pressure supply method of supplying by extrusion by pressure, whereby the coating liquid from the nozzle Patent documents 1 and 2 are known as a coating device which was made to carry out the application processing of a coating subject by making it eject.

  The "slit type coating apparatus" of Patent Document 1 has an object of providing a slit type coating apparatus which obtains a uniform coating film by controlling the discharge amount of the chemical solution at the start and end of the coating without increasing the equipment cost. And a mechanism having a normally-closed single-acting chemical valve for performing ON / OFF of the application chemical solution supply, and driving (control) opening / closing of the chemical solution valve valve. Slit coater comprising a mechanism having an electro-pneumatic regulator capable of freely changing the air pressure for the control by an electrical signal from the controller, and a mechanism having a controller for transmitting the electrical signal to the regulator It is supposed to be. In Patent Document 1, the chemical solution is pressurized to the pressurized tank by the precision regulator and supplied to the position immediately before the valve of the chemical solution valve, and the valve of the chemical solution valve is opened by the air pressure of the electropneumatic regulator set. The chemical solution is supplied to the slit nozzle.

  The "substrate processing apparatus and liquid transfer apparatus" of Patent Document 2 has an object to provide an apparatus for transferring the processing liquid with high accuracy without generating particles, and the resist liquid (processing liquid (processing liquid) A resist pump and a driving mechanism are provided in a liquid feeding mechanism for feeding liquid. Further, the resist pump is provided with a small diameter first bellows, a large diameter second bellows, a joint member of the first bellows and the second bellows, and a tube serving as a flow path of the resist solution. When the drive mechanism moves the bonding member downward, the internal volume of the tube is reduced, and the resist solution in the tube is sent to the slit nozzle. Further, when the drive mechanism moves the bonding member downward, the internal volume of the tube is increased, and the resist solution is sucked by the resist pump. In Patent Document 2, a substrate processing apparatus includes a replenishment device, a buffer tank, and a sensor as a supply mechanism for supplying a resist solution, and the buffer tank mixes the resist solution by temporarily storing the resist solution. The control system controls the buffer tank so that the resist solution is sent to the slit nozzle by the atmospheric pressure.

JP 2002-254008 A Unexamined-Japanese-Patent No. 2004-281640

  FIG. 5 shows the basic configuration of the pressure supply system. A coating liquid replenishment system d having a coating liquid replenishment on / off valve c is connected to the tank a of the airtight structure to replenish the coating liquid b, and for introducing a pressurizing gas such as air to the tank a And a gas introduction system f having a gas introduction on-off valve e is connected. While the gas introduced into the tank a is pressurized so that the inside of the tank a is maintained at a predetermined constant pressure value, the pressurization pushes the coating liquid b out of the tank a.

  A coating liquid supply system i having an on-off valve h is provided between the tank a and the nozzle g in order to supply and discharge the coating liquid b pushed out of the tank a to the nozzle g. The nozzle g and the object to be coated j are moved relative to each other, whereby the object to be coated j is coated with the coating liquid b discharged from the nozzle g.

  At the time of applying the coating object j, the coating solution b for at least one coating process is replenished and stored in the tank a in advance from the coating solution replenishment system d. The gas introduced into the inside of the tank a by opening the on-off valve e for gas introduction pushes the coating liquid b from the tank a to the coating liquid supply system i by its pressurizing action.

  Specifically, gas is continuously introduced into the inside of the tank a according to the decrease of the coating liquid b inside the tank a due to the extrusion of the coating liquid b, whereby the inside of the tank a is maintained at a predetermined constant pressure value. The pressing action of pushing out the coating solution b is maintained.

  The coating solution b pushed out from the tank a pressurized to a constant pressure value is supplied to the nozzle g through the open on-off valve h, and the coating solution b supplied to the nozzle g is an object to be coated from the nozzle g Discharge is always performed at a constant discharge pressure toward j, and pressure fluctuation does not occur during discharge. Thus, the object to be coated j has the advantage of being coated with a constant coating thickness.

  When the coating process is started, generally, the coating solution b is substantially filled from the inside of the tank a to the inside of the nozzle g, and the on-off valve h of the coating solution supply system i is closed to block the flow of the coating solution b. ing. At this time, a gas is introduced into the tank a in order to supply the coating liquid b in response to the start of the coating process, and the inside of the tank a is pressurized to a predetermined constant pressure value by this gas. Therefore, the coating solution b is already pushed out from the tank a to the on-off valve h.

  For this reason, when the on-off valve h is opened, although the inside of the tank a has a substantially predetermined constant pressure value, the coating liquid b is directed toward the nozzle g by the instantaneous opening of the on-off valve h which was in the closed state. It flows at once, and as shown by the graph in FIG. 5, regardless of the constant pressure state inside the tank a, the nozzle g is discharged with a larger discharge amount.

  As a result, when the coating process is started, for example, at the coating start end k to which the coating solution b discharged from the nozzle g is first applied, the coating solution b is raised as shown by the m portion in the figure. was there.

  The present invention has been made in view of the above-mentioned conventional problems, and even in the pressure supply method, the coating liquid to be discharged from the nozzle at the beginning of the coating process is raised and applied when the coating process is started. The coating can be applied to the object to be coated with an appropriate coating thickness from the start of the coating treatment, and the coating is simple and easy to control for coating thickness adjustment. It aims at providing an apparatus and a coating method.

The coating apparatus according to the present invention is connected to a coating liquid supply source for extruding and supplying the coating liquid stored in the tank to the coating liquid supply system by pressurization with a constant pressure value, and the coating liquid supply system. The coating liquid is moved relative to the object to be coated while discharging the coating liquid supplied, and is provided in the nozzle for coating the coating object and the coating liquid supply system, and the coating liquid is raised at least at the coating start end A syringe pump in which the amount of the coating liquid having a compressible and absorbable volume is filled, and the coating liquid supply system disposed between the syringe pump and the nozzle; a syringe pump for filling off valve which is closed only when supplying a coating liquid from the coating liquid supply source to the pump, to the coating liquid supply system, provided disposed between the syringe pump and the coating liquid supply source and a opening and closing valve, the opening and closing Before the start of coating, in which the coating liquid is filled up with the inside of the syringe pump, and the on-off valve is closed to shut off the flow of the coating liquid being pushed out from the tank; At the start of processing, the syringe pump filling on-off valve is opened, and the coating liquid is supplied to the nozzle and discharged by the driven syringe pump to perform coating in the initial stage; coating by stopping the driving of the syringe pump When the on-off valve is opened simultaneously with the stop of the liquid supply and the coating liquid flows from the tank to the nozzle all at once, the flow of the coating liquid is caused by the volume of the syringe pump and the compression elasticity of the coating liquid itself. It is characterized in that it is buffered to suppress a change in pressure transmitted from the tank to the nozzle through the coating liquid supply system .

In the coating method according to the present invention, the on-off valve is opened in a state where the on-off valve for filling the syringe pump is closed using the application apparatus, and the application liquid supply source via the application liquid supply system The coating liquid is supplied to the syringe pump, and the coating liquid is filled between the on-off valve and the nozzle, and the inside of the syringe pump is filled with the coating liquid. In order to shut off the flow, the on-off valve is closed, and at the start of the coating process, the on-off valve for filling the syringe pump is opened, and the coating liquid is supplied to the nozzle and discharged by the driven syringe pump. When the coating liquid flows from the tank to the nozzle all at once, the on-off valve is opened simultaneously with the stopping of the coating liquid supply due to the driving stop of the syringe pump. The compressive elastic capacity and coating solution itself Njiponpu, and buffered water撃的flow of the coating liquid, it suppresses changes in pressure to be propagated from the tank to the nozzle through the coating liquid supply system It features.

In the coating apparatus and the coating method according to the present invention, even in the pressure supply method, it is possible to suppress the coating liquid, which is first discharged from the nozzle when the coating processing is started, from being raised and coated. While being able to apply | coat to a coating target object with a suitable coating film thickness from the start time of a coating process, the structure is simple and control for coating film thickness adjustment can also be facilitated. In detail, only in the initial stage of the coating process where it is necessary to suppress the excessive discharge of the coating liquid accompanying the opening of the on-off valve, there is no jump out of the coating liquid played by the syringe pump using the syringe pump (in tank pressurization) Taking advantage of the fact that the coating liquid does not swell at the coating start end, immediately after that, the advantage of the extrusion of the coating liquid from the tank, ie, securing a stable discharge rate (in the case of a syringe pump, fear of discharge fluctuation due to chattering) Switching to the coating process that takes advantage of the advantages of (1), and excessive flow of coating liquid at this switched moment can be prevented by the buffer function of the syringe pump, so that the coating liquid swells at the start of the coating process. It is possible to continuously prevent the prevention and the subsequent uniformization of the coating thickness. The syringe pump is simply provided in the coating liquid supply system, the configuration is extremely simple, and the control for adjusting the thickness of the coating film is also simple and simple by simultaneously stopping the syringe pump and opening the on-off valve. , Can be implemented easily.

It is a schematic block diagram which shows 1st Embodiment of the coating device which concerns on this invention, and the coating method. It is a schematic block diagram which shows 2nd Embodiment of the coating device which concerns on this invention, and the coating method. It is a schematic block diagram which shows 3rd Embodiment of the coating device which concerns on this invention, and the coating method. It is a schematic block diagram which shows 4th Embodiment of the coating device which concerns on this invention, and the coating method. It is a schematic block diagram of the conventional coating device.

  Hereinafter, preferred embodiments of a coating apparatus and a coating method according to the present invention will be described in detail with reference to the attached drawings. FIG. 1 shows a schematic configuration of the coating apparatus and the coating method according to the first embodiment.

  The coating apparatus 1 according to the first embodiment includes a coating liquid supply source 2. The coating liquid supply source 2 is connected to the tank 3 having an airtight structure for storing the coating liquid b, the tank 3 and the coating liquid replenishment system 4 for replenishing the coating liquid b to the tank 3 and the tank 3. A gas introduction system 5 for introducing a gas such as air into the tank 3 and a pressure gauge 6 indicating the pressure in the tank 3 are provided to pressurize the inside to a predetermined constant pressure value.

  The coating liquid replenishment system 4 is provided with a coating liquid replenishment on-off valve 7 that replenishes the tank 3 with the coating liquid b by being opened and is closed by stopping the replenishment of the coating liquid b. The coating liquid b for at least one coating process is replenished and stored in the tank 3 in advance before the start of the coating process.

  The gas introduction system 5 is provided with a gas introduction on-off valve 8 for introducing a pressurizing gas into the tank 3 by being opened and closing the gas introduction system 5. The gas introduced into the inside of the tank 3 is pressurized so that the inside of the tank 3 is maintained at a predetermined constant pressure value, and by this pressurization, the coating liquid b stored in the inside of the tank 3 is pushed out from the tank 3 And supply to a coating liquid supply system 9 described later.

  Specifically, the gas is continuously introduced into the tank 3 according to the decrease of the coating solution b inside the tank 3 due to the extrusion of the coating solution b, whereby the inside of the tank 3 is maintained at a predetermined constant pressure value. The pressure action of pushing out the coating liquid b is maintained while being raised. The constant pressure value inside the tank 3 can be confirmed by the pressure gauge 6.

  One end of a coating liquid supply system 9 is connected to the tank 3 of the coating liquid supply source 2, and the coating liquid b pushed out from the tank 3 is supplied and circulated. The other end of the coating liquid supply system 9 discharges the coating liquid b supplied through the coating supply system 9, and the nozzle 12 applies the coating object 11 such as a substrate placed on the base 10. Connected

  When the nozzle 12 is discharging the coating liquid b, one of the nozzle 12 and the base 10 is moved relative to the other or both by the moving mechanism (not shown). The object to be coated 11 is coated with the coating liquid b discharged from the nozzle 12. The coating process is generally started from the coating start end 11a which is one end in the lengthwise direction of the coating object 11, and is performed toward the coating end (not shown) which is the other end in the lengthwise direction of the coating object 11. .

  The coating liquid supply system 9 provided between the nozzle 12 and the tank 3 is provided with an on-off valve 13a. The on-off valve 13a is opened to supply the coating liquid b from the tank 3 (coating liquid supply source 2) to the nozzle 12, and is closed to stop the supply of the coating liquid b to the nozzle 12. Therefore, the on-off valve 13a is operated to open when the coating process is started, and the open state is maintained during the coating process. In addition, the closing operation is performed when the coating process is not performed, such as when the coating process is completed, and the closed state is maintained.

  The opening and closing of the on-off valve 13a may be manual or may be automatically controlled.

  The coating liquid supply system 9 is provided with a buffer tank 15. The coating liquid supply system 9 is composed of two systems of a tank side system line 9a connected to the tank 3 and a nozzle side system line 9b connected to the nozzle 12. The ends of these lines 9a and 9b are buffer The buffer tank 15 is interposed in the coating liquid supply system 9 by being inserted into the tank 15. In the present embodiment, the on-off valve 13a of the coating liquid supply system 9 is provided in the tank side system passage 9a.

  The inside of the buffer tank 15 is filled with the coating solution b. The filling of the coating liquid b into the buffer tank 15 may be carried out in advance by opening the on-off valve 13 a and feeding it from the tank 3.

  When the coating process is started, the coating liquid b is usually filled from the inside of the tank 3 to the inside of the nozzle 12, and the on-off valve 13a is closed to block the flow of the coating liquid b. At this time, a gas is introduced into the tank 3 in order to supply the coating liquid b in response to the start of the coating process, and the inside of the tank 3 is pressurized to a predetermined constant pressure value by this gas. Accordingly, the coating solution b is already pushed out of the tank 3 toward the on-off valve 13a.

  When the on-off valve 13a is opened, the inside of the tank 3 has a substantially predetermined constant pressure value, but when the on-off valve 13a in the closed state is opened instantly, the constant pressure state of the inside of the tank 3 In the coating liquid supply system 9, a change in pressure transmitted to the nozzle 12 occurs.

  The buffer tank 15 suppresses this pressure change that occurs when the on-off valve 13a is opened. The coating liquid b is not completely incompressible fluid and has compression elasticity, so that the coating liquid b flowing from the tank side passage 9a into the buffer tank 15 has a large volume of buffer by opening the on-off valve 13a. By the tank 15, a water hammer phenomenon flowing at once is buffered by the compression elasticity of the coating liquid b itself inside the buffer tank 15. Thereby, when the on-off valve 13a is opened, a change in pressure transmitted toward the nozzle 12 through the coating liquid supply system 9 is suppressed.

  The operation of the coating apparatus 1 according to the first embodiment will be described. At the preparation stage before starting the coating process, the coating solution b is replenished and stored in the tank 3 from the coating solution replenishment system 4, and then a gas for pressurization is introduced from the gas introduction system 5 into the tank 3. The inside of the tank 3 is pressurized to a predetermined constant pressure value.

  At this time, the on-off valve 13a of the coating liquid supply system 9 is closed to block the flow of the coating liquid b, and the coating liquid b is pushed out from the tank 3 toward the on-off valve 13a. At this time, between the on-off valve 13 a and the nozzle 12, the coating liquid b is filled, and the inside of the buffer tank 15 is also filled.

  When the application process is started from the application start end 11 a of the application object 11 placed on the base 10, the on-off valve 13 a of the application liquid supply system 9 is opened. When the on-off valve 13a is opened, although the inside of the tank 3 has a substantially predetermined constant pressure value, the coating liquid b is allowed to flow toward the nozzle 12 at once by opening the on-off valve 13a which has been closed. Do.

  The coating solution b circulated from the on-off valve 13a position flows into the buffer tank 15 located closer to the nozzle 12 than the on-off valve 13a. The buffer tank 15 can buffer the water-like flow of the coating liquid b by the large volume and the compression elasticity of the coating liquid b itself as described above, and the coating liquid supply system 9 is directed to the nozzle 12 It is possible to suppress the change in the pressure that propagates. Therefore, the volume of the coating solution b stored in the buffer tank 15 needs to be at least a volume capable of absorbing the amount of swelling of the coating solution b at the coating start end 11 a by compression elasticity.

  The buffer tank 15 suppresses the pressure change caused by the opening of the on-off valve 13a, and the coating liquid b corresponding to the flow rate of the coating liquid flowing into the buffer tank 15 from the tank side system passage 9a flows from the buffer tank 15 to the nozzle side. It is supplied to the nozzle 12 via the line 9 b. Therefore, as shown in the graph in FIG. 1, the discharge amount of the coating liquid b discharged from the nozzle 12 is approximately equal to the start of the coating process without rapidly rising even when the on-off valve 13 a is opened. Discharge is performed at a discharge amount corresponding to a predetermined constant pressure value applied inside the tank 3.

  Thereby, when the on-off valve 13a is opened to start the coating process, it is possible to suppress that the coating liquid b discharged from the nozzle 12 is raised and applied first. Therefore, the coating solution b can be discharged from the nozzle 12 in a substantially constant amount from the start of the coating process to the subsequent continuous coating process, and the coating object 11 can be coated with an appropriate coating thickness. it can.

  The coating apparatus 1 according to the first embodiment is simply provided with the buffer tank 15 in the coating liquid supply system 9, and the configuration is extremely simple, and no special control for the thickness adjustment of the coating film is necessary, which is easy. It can be implemented.

  The schematic structure of the coating device and the coating method which concern on 2nd Embodiment is shown by FIG. In the coating device 16 of the second embodiment, the buffer tank 17 is configured of a variable volume type. The buffer tank 17 is provided with a shaft 18 whose push amount into the buffer tank 17 can be adjusted in order to change its volume. The capacity of the buffer tank 17 can be reduced by increasing the amount of pushing of the shaft 18 into the buffer tank 17, and the capacity can be increased by decreasing the amount of pushing.

  Unlike the first embodiment, by providing the variable-capacity buffer tank 17, the responsiveness of the flow of the coating liquid b when the on-off valve 13a is opened is adjusted, that is, when the coating process is started The amount of discharge of the coating solution b discharged first can be increased or decreased, and adjustment can be easily performed so that the buildup of the coating solution b at the coating start end 11 a disappears. Even in such a second embodiment, the same function and effect as those of the first embodiment can be obtained.

  FIG. 3 shows a schematic configuration of a coating apparatus and a coating method according to the third embodiment. Basically, in the coating device 19 of the third embodiment, in place of the buffer tanks 15 and 17, a syringe pump 20 having a function of discharging the coating liquid b by itself is used. The syringe pump 20 is located between the on-off valve 13a provided in the tank side system line 9a and the on-off valve 13b for filling the syringe pump provided in the nozzle side system line 9b. , And is provided in the coating liquid supply system 9.

  Thereby, the syringe pump 20 is arrange | positioned between the on-off valve 13a and the syringe pump filling on-off valve 13b. The syringe pump 20 drives the piston rod 20a with the motor 20b to supply the coating liquid b accumulated between the piston 20c and the cylinder 20d in a full state, to the outside of the syringe pump 20, which is the coating liquid supply in this embodiment. It is designed to be pushed into line 9. As well known, the syringe pump 20 has a function of adjusting the amount of extrusion of the liquid or gas such as the coating liquid b with high accuracy, and a situation where the coating liquid b is raised at the coating start end 11a at the start of discharge. There is an advantage that does not occur.

  The filling of the coating solution b into the syringe pump 20 may be carried out in advance by opening the on-off valve 13a and closing the on-off valve 13b for filling the syringe pump from the tank 3. The syringe pump filling on-off valve 13b is kept open except when the coating solution b is fed. As in the case of the buffer tank 15 of the first and second embodiments, the amount of the coating solution b stored in the syringe pump 20 is at least an amount by which the coating solution b bulges at the coating start end 11 a by compression elasticity. It needs an amount that can be absorbed.

  A large volume of syringe pump 20 buffers the water hammer phenomenon flowing at once by the compression elasticity of the coating liquid b itself inside the syringe pump 20. Thereby, when the on-off valve 13a is opened in a state in which the on-off valve 13b for filling the syringe pump is opened, a change in pressure transmitted toward the nozzle 12 through the coating liquid supply system 9 is suppressed.

  The extrusion of the coating solution b by the syringe pump 20 is performed in a state where the on-off valve 13a is closed. On the other hand, the on-off valve 13a is opened in a state where the coating liquid b is stored so as to be filled between the piston 20c and the cylinder 20d.

  Specifically, when the coating process is started, the syringe pump 20 supplies the coating solution b to the nozzle 12 in a state in which the on-off valve 13a is closed (the on-off valve 13b for filling the syringe pump is open). On the other hand, unlike the first and second embodiments which are opened when the coating process is started, the on-off valve 13a is opened accordingly in response to the stop of the supply of the coating liquid b by the syringe pump 20.

  The coating method by the coating device of 3rd Embodiment is demonstrated. The preparation steps before starting the coating process are the same as in the first and second embodiments. The on-off valve 13a of the coating liquid supply system 9 is closed and the flow of the coating liquid b is shut off, and the coating liquid b is pushed out from the tank 3 toward the on-off valve 13a. At this time, the coating liquid b is filled and the inside of the syringe pump 20 is also filled with the coating liquid b between the on-off valve 13 a and the nozzle 12.

  When the coating process is started, the coating solution b is supplied to the nozzle 12 by the syringe pump 20 driven by the motor 20b in a state where the on-off valve 13a is closed (syringe pump filling on-off valve 13b is opened). The coating liquid b is discharged from the nozzle 12 to perform application in the initial stage. Immediately after that, when the supply of the coating liquid b to the nozzle 12 by the syringe pump 20 is stopped by stopping the motor 20b in order to continue the coating process, the coating liquid supply system 9 accordingly. The on-off valve 13a is opened.

  When the on-off valve 13a is opened, although the inside of the tank 3 has a substantially predetermined constant pressure value, the coating liquid b is allowed to flow toward the nozzle 12 at once by opening the on-off valve 13a which has been closed. However, as in the first and second embodiments, as described above, the syringe pump 20 buffers the water hammering flow of the coating liquid b by its large volume and the compressive elasticity of the coating liquid b itself. It is possible to suppress the change in pressure propagating from the tank 3 to the nozzle 12 via the coating liquid supply system 9.

  Thereby, as shown in the graph in FIG. 3, the discharge amount of the coating liquid b discharged from the nozzle 12 does not rise sharply even by opening the on-off valve 13a, and the application in the initial stage by the syringe pump 20 Subsequently, the discharge amount corresponding to the predetermined constant pressure value applied to the inside of the tank 3 is discharged.

  Thus, when the coating process is started, the coating liquid b first discharged from the nozzle 12 is raised and applied by opening the syringe pump 20 capable of controlling the discharge amount with high accuracy and the on-off valve 13a following it. Can be suppressed. Therefore, the coating solution b can be discharged from the nozzle 12 in a substantially constant amount from the start of the coating process to the subsequent continuous coating process, and the coating object 11 can be coated with an appropriate coating thickness. it can.

  In addition, since fine chattering occurs due to the friction between the piston 20c and the cylinder 20d when the syringe pump 20 is driven by the motor 20b, there is a risk that the coating film thickness may be minute in the coating process using only the syringe pump 20 .

  The syringe pump 20 can be said to be a variable displacement buffer tank 17, and adjusts the responsiveness of the flow of the coating liquid b when the on-off valve 13a is opened, that is, from the nozzle 12 first when starting the coating process. It can adjust by increasing or decreasing the discharge amount of the coating liquid b discharged.

  In the third embodiment, the syringe pump 20 is used only for the initial stage of the coating process where it is necessary to suppress the excessive discharge of the coating solution b accompanying the opening of the on-off valve 13a. Taking advantage of the fact that there is no jump out (there is jump out in tank pressurization), ie taking advantage of the fact that the coating solution b does not swell at the coating start end 11a, immediately thereafter, the advantage by the extrusion of the coating solution b from the tank 3, ie stable discharge rate Switching to the coating process that takes advantage of the advantage of ensuring the possibility of discharge fluctuation due to chattering in the syringe pump 20, and the excessive flow of the coating liquid b at this switched moment as a buffer tank of the syringe pump 20. Of the coating solution b at the start of the coating process and the thickness of the coating film after that. It can be ensured continuously and Ichika a series.

  Even in such a third embodiment, the same function and effect as those of the first and second embodiments can be obtained.

  The coating apparatus 19 according to the third embodiment only has the syringe pump 20 provided in the coating liquid supply system 9, and the configuration is extremely simple, and control for coating film thickness adjustment is also performed by stopping the syringe pump 20. The opening and closing of the on-off valve 13a can be performed simply and simultaneously and easily.

  FIG. 4 shows a schematic configuration of a coating apparatus and a coating method according to the fourth embodiment. The coating device 21 of the fourth embodiment is basically added to the configuration of the first embodiment, and an additional coating liquid supply system 22 having a syringe pump 20 is arranged in parallel with the coating liquid supply system 9 to form a tank 3. And the nozzle 12 is provided.

  The syringe pump 20 is connected between the tank side system passage 22a of the additional coating liquid supply system 22 and the nozzle side system passage 22b in substantially the same manner as described above, at the ends of the two system passages 22a and 22b. An additional coating liquid supply system 22 is provided. As in the third embodiment, the on / off valve 13 b and the added on / off valve 13 c are provided in the two system paths 22 a and 22 b so as to sandwich the syringe pump 20. Thus, the syringe pump 20 is disposed between the tank 3 and the nozzle 12. The syringe pump 20 is configured to push the coating solution b accumulated between the piston 20 c and the cylinder 20 d in a full state to the additional coating solution supply system 22. The on-off valves 13b and 13c are operated similarly to the on-off valves 13b and 13a of the third embodiment. That is, the on-off valve 13 b is closed only when the coating liquid b is fed to the syringe pump 20.

  The syringe pump 20 is provided in the additional coating liquid supply system 22 in the fourth embodiment and is not provided in the coating liquid supply system 9 having the on-off valve 13a, so that the pressure generated when the on-off valve 13a is opened It is not necessary to provide the function of suppressing the change, and therefore, unlike the case of the third embodiment, it is formed with a small volume. Similar to the first and second embodiments, the pressure change suppressing action is achieved by the buffer tank 15 (which may be a variable displacement buffer tank 17).

  When the coating process is started, the additional coating liquid supply is performed with the on / off valve 13 c closed and the on / off valve 13 a of the coating liquid supply system 9 closed to prevent backflow to the tank 3 when the coating process is started. The coating solution b is supplied to the nozzle 12 through the system 22. On the other hand, unlike the first and second embodiments which are opened when the coating process is started, the on-off valve 13a is opened in response to the supply stop of the coating solution b by the syringe pump 20, whereby the coating solution from the tank 3 The coating solution b is supplied to the nozzle 12 through the supply system 9.

  The coating method by the coating device 21 of the fourth embodiment will be described. The preparation steps before starting the coating process are the same as in the first to third embodiments. The on-off valve 13a of the coating liquid supply system 9 is closed and the flow of the coating liquid b is shut off, and the coating liquid b is pushed out from the tank 3 toward the on-off valve 13a.

  At this time, in the coating liquid supply system 9, the coating liquid b is filled between the on-off valve 13a and the nozzle 12, and the additional coating liquid supply system 22 extends from the tank 3 to the nozzle 12 as well. And the inside of the syringe pump 20 is also filled with the coating liquid b. In order to prevent backflow to the tank 3, the on-off valve 13c is closed.

  When the coating process is started, the coating liquid b is supplied to the nozzle 12 via the additional coating liquid supply system 22 by the syringe pump 20 driven by the motor 20 b in a state where the on-off valve 13a is closed. The coating solution b is discharged to perform application in the initial stage. Immediately after that, when the supply of the coating liquid b to the nozzle 12 by the syringe pump 20 is stopped by stopping the motor 20b in order to continue the coating process, the coating liquid supply system 9 accordingly. The on-off valve 13a is opened.

  When the on-off valve 13 a is opened, the coating liquid b is supplied from the tank 3 to the nozzle 12 through the coating liquid supply system 9. When the coating solution b flows through the coating solution supply system 9, as in the first and second embodiments, as described above, the buffer tank 15 has the large volume and the compression elasticity of the coating solution b itself. It is possible to buffer the water-like flow of the liquid b, and it is possible to suppress a change in pressure propagating from the tank 3 through the coating liquid supply system 9 toward the nozzle 12.

  Thereby, as shown in the graph in FIG. 4, the discharge amount of the coating liquid b discharged from the nozzle 12 does not rise sharply even when the on-off valve 13 a is opened, and the application at the initial stage by the syringe pump 20 Subsequently, the discharge amount corresponding to the predetermined constant pressure value applied to the inside of the tank 3 is discharged.

  As described above, when the coating process is started by the syringe pump 20 capable of controlling the discharge amount with high accuracy and the pressure buffering action of the buffer tank 15 for the subsequent opening of the on-off valve 13a, the nozzle is first discharged from the nozzle 12 It is possible to prevent the coating solution b from being raised and applied. Therefore, the coating solution b can be discharged from the nozzle 12 in a substantially constant amount from the start of the coating process to the subsequent continuous coating process, and the coating object 11 can be coated with an appropriate coating thickness. it can.

  Even in the fourth embodiment, of course, only at the initial stage of the coating process where it is necessary to suppress the excessive discharge of the coating solution b accompanying the opening of the on-off valve 13a, the syringe pump 20 is used and Switching to a coating process with a stable discharge amount by the extrusion of the coating solution b, and buffering excessive discharge of the coating solution b immediately after the switching by the buffer tank 15, preventing the coating solution b from rising at the start of the coating process and , And subsequent uniformization of the coating film thickness can be ensured. Even in such a fourth embodiment, the same operation and effect as those of the first to third embodiments can be obtained.

  The coating apparatus 21 according to the fourth embodiment is only provided with an additional coating liquid supply system 22 including the syringe pump 20 in the configuration of the first embodiment, and the configuration is extremely high, such as the capacity of the syringe pump 20 can be reduced. As it is simple, as in the third embodiment, it can be easily implemented with a simple control of stopping the syringe pump 20 and opening the on-off valve 13a simultaneously.

  It goes without saying that the buffer tank 15 may be of the variable displacement type described in the second embodiment, whereby the thickness of the coating film can be adjusted more freely.

1,16,19,21 Coating apparatus 2 Coating liquid supply source 3 Tank 4 Coating liquid replenishment system 5 Gas introduction system 6 Pressure gauge 7 On-off valve for coating liquid replenishment 8 On-off valve for gas introduction 9 Coating liquid supply system 9a Tank side system Route 9b Nozzle side system route 10 Base 11 Application target 11a Application start end 12 nozzle 13a, 13b, 13c Open / close valve 15 Buffer tank 17 Variable displacement buffer tank 18 Shaft 20 Syringe pump 20a Piston rod 20b Motor 20c Piston 20d Cylinder 22 added Coating solution supply system 22a Tank side system route 22b Nozzle side system route a Tank b Coating solution c Coating solution on-off valve d Coating solution replenishment system e Gas introducing on-off valve f Gas introducing system g Nozzle h on-off valve i Coating solution Supply system j Application object k Application start end m Coating liquid buildup

Claims (2)

A coating liquid supply source that extrudes and supplies the coating liquid stored in the tank to the coating liquid supply system by pressurization with a constant pressure value ;
A nozzle that is connected to the coating liquid supply system and discharges the supplied coating liquid while being moved relative to the coating object to apply the coating object;
A syringe pump provided in the coating liquid supply system and filled with the coating liquid having a volume capable of being absorbed by the compression elasticity of the coating liquid at least at an amount at which the coating liquid rises at the coating start end ;
A syringe pump filling on / off valve disposed in the coating solution supply system between the syringe pump and the nozzle and closed only when the coating solution is supplied from the coating solution supply source to the syringe pump;
The coating liquid supply system includes an open / close valve disposed between the syringe pump and the coating liquid supply source ,
The opening and closing valve is closed in order to block the flow of the coating liquid which is being pushed out from the tank before the start of application where the coating liquid is filled in the interval from the on-off valve to the nozzle and inside the syringe pump. At the start of the coating process, the on-off valve for filling the syringe pump is opened and the coating liquid is supplied to the nozzle and discharged by the syringe pump which is driven to perform coating in the initial stage; driving the syringe pump When the coating valve flows from the tank to the nozzle all at once simultaneously with the stop of the coating liquid supply due to the stop, the volume of the syringe pump and the compression elasticity of the coating liquid itself make the coating liquid water hammer The coating apparatus is characterized in that the flow is buffered to suppress a change in pressure transmitted from the tank to the nozzle through the coating liquid supply system . Using the coating device according to claim 1,
In a state where the syringe pump filling on-off valve is closed, the on-off valve is opened, and the coating liquid is supplied from the coating liquid supply source to the syringe pump through the coating liquid supply system,
The opening and closing valve is closed to shut off the flow of the coating liquid which is being pushed out from the tank before the start of the application in which the coating liquid is filled between the on-off valve and the nozzle and the inside of the syringe pump. And
At the start of the coating process, the on-off valve for filling the syringe pump is opened, and the coating liquid is supplied to the nozzle and discharged by the driven syringe pump to perform coating in the initial stage.
Thereafter, when the coating liquid flows from the tank to the nozzle all at once when the coating liquid supply is stopped by stopping the driving of the syringe pump and the coating liquid flows from the tank to the nozzle all at once, by the compression elasticity of the coating liquid itself A coating method characterized by buffering a water-like flow of a coating liquid and suppressing a change in pressure transmitted from the tank to the nozzle via the coating liquid supply system .

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