JP2016150310A - Deaeration device, coating applicator and deaeration method - Google Patents

Abstract

A degassing apparatus capable of efficiently removing dissolved gas in a high-viscosity liquid, a coating apparatus equipped with the degassing apparatus, and a degassing method are provided. A deaeration device 60 connects a first tank 81 as a supply source and a second tank 82 as a supply destination, and has a main pipe 61 having a horizontal portion 611 extending substantially horizontally, and upward from the horizontal portion 611. And a deaeration pipe 62 that extends. When removing the dissolved gas in the liquid L, first, the deaeration pipe 62 is filled with the liquid L. Next, a liquid flow toward the downstream side is formed in the main pipe 61 while reducing the pressure in the pipe. Bubbles generated in the liquid due to the reduced pressure are collected at the upper edge of the main pipe 61 by the flow of the liquid L in the main pipe 61. For this reason, the bubbles enter the deaeration pipe 62 from the horizontal portion 611 of the main pipe 61. Thereafter, the air bubbles accumulated in the deaeration pipe 62 are discharged. [Selection] Figure 4

Description

  The present invention relates to a deaeration device that removes dissolved gas in a liquid, a coating device that includes the deaeration device, and a deaeration method that removes dissolved gas in a liquid.

  Conventionally, glass substrates for liquid crystal display devices, semiconductor wafers, glass substrates for PDP, glass substrates for photomasks, substrates for color filters, substrates for recording disks, substrates for solar cells, substrates for electronic paper, etc. In the manufacturing process, a coating apparatus that applies a liquid such as a photoresist to the surface of a substrate is used. A conventional coating apparatus is described in Patent Document 1, for example. The coating apparatus of Patent Document 1 discharges a coating solution from a slit die having a slit-shaped discharge port to a substrate held by suction on a stage movable in a horizontal direction.

JP 2009-2441056 A

  In this type of coating apparatus, when dissolved gas exists in the liquid, so-called “bubble bubbles” are likely to occur in the slit die. When “bubble bubbles” occur, liquid cannot be applied uniformly from the discharge port, and the uniformity of the coating film may be reduced. For this reason, the deaeration process which removes dissolved gas from the liquid before application | coating conventionally is performed. In the conventional coating apparatus, the dissolved gas in the liquid is bubbled in advance by setting the inside of the container in which the liquid before coating is stored to a negative pressure. When the viscosity of the liquid is low, bubbles generated in the liquid can be easily lifted to the liquid surface and discharged out of the container.

  However, when a highly viscous liquid is used, it takes a very long time for the bubbles to rise to the liquid surface. In particular, fine bubbles tend to hardly float. For this reason, in the conventional method, there exists a problem that deaeration cannot be performed efficiently with respect to a highly viscous liquid. In recent years, in the manufacturing process of flexible devices and batteries, there is an increasing demand for apparatuses that apply a high-viscosity liquid to the surface to be processed. In connection with this, the technique which can remove dissolved gas from a highly viscous liquid efficiently is calculated | required.

  This invention is made | formed in view of such a situation, and provides the deaeration apparatus which can remove efficiently the dissolved gas in the liquid with a high viscosity, the coating device provided with the said deaeration apparatus, and the deaeration method For the purpose.

  In order to solve the above problems, a first invention of the present application is a deaeration device for removing dissolved gas in a liquid, which connects a first tank of a supply source and a second tank of a supply destination and extends substantially horizontally. A main pipe having a horizontal part; a deaeration pipe extending upward from the horizontal part; a plurality of valves provided in the main pipe and the deaeration pipe; and the second tank side in the main pipe A pressure reducing unit that generates an upward suction force and generates an upward suction force in the deaeration pipe; and a control unit that controls the plurality of valves and the pressure reduction unit. A) filling the deaeration pipe with liquid by controlling the section and the plurality of valves; and b) forming a liquid flow downstream in the main pipe after the step a). C) after the step b), the degassing Implementing a step of discharging the bubbles accumulated in the tube, the.

  2nd invention of this application is a deaeration apparatus of 1st invention, Comprising: These valves are 1st valves provided in the upstream rather than the connection part with the said deaeration piping on the path | route of the said main piping. A second valve provided on the downstream side of a connection portion with the deaeration pipe on the path of the main pipe, and a third valve provided on the path of the deaeration pipe, The control unit closes the second valve and opens the first valve and the third valve in the step a), and closes the third valve and closes the second valve in the step b). In the step c), the third valve is opened, and bubbles accumulated below the third valve of the deaeration pipe are discharged upward.

  3rd invention of this application is a deaeration apparatus of 2nd invention, Comprising: The said deaeration piping is a 1st vertical pipe extended upwards from the said horizontal part, and said 1st vertical pipe from the upper end of the said 1st vertical pipe A horizontal pipe extending laterally at an angle closer to the horizontal than the vertical pipe, and a second vertical pipe extending upward from the other end of the horizontal pipe, wherein the third valve is provided in the second vertical pipe. Is provided.

  4th invention of this application is a deaeration apparatus of 3rd invention, Comprising: The edge part by the side of the 2nd vertical pipe of the said horizontal pipe is the height equivalent to the edge part by the side of the 1st vertical pipe of the said horizontal pipe, Alternatively, the angle of the horizontal pipe with respect to the horizontal plane is 0 ° or more and 45 ° or less.

  5th invention of this application is a deaeration apparatus of 3rd invention or 4th invention, Comprising: The said 2nd vertical pipe has a volume more than the said horizontal pipe.

  6th invention of this application is a deaeration apparatus of any one invention from 2nd invention to 5th invention, Comprising: The said deaeration piping is the 1st deaeration piping extended toward the upper direction at least from the said horizontal part. And a second deaeration pipe extending upward from a position downstream of the first deaeration pipe of the horizontal portion, wherein the first valve is located on the path of the main pipe. The second valve is provided on the upstream side of the connection portion with the degassing pipe, and the third valve is provided on the downstream side of the connection portion with the second degassing pipe on the path of the main pipe. Is provided on each path of the first deaeration pipe and the second deaeration pipe.

  7th invention of this application is a deaeration apparatus of 6th invention, Comprising: The upper end part of the said 1st deaeration piping and the upper end part of the said 2nd deaeration piping are slanting piping extended toward diagonally upward. Connected to one discharge pipe.

  The eighth invention of the present application is the deaeration device according to any one of the second to seventh inventions, further comprising a fourth valve provided between the deaeration pipe and the pressure reducing part. From the step a) to the step c), the fourth valve is opened.

  A ninth invention of the present application is the deaeration device according to any one of the first to eighth inventions, further comprising a heater for heating the liquid in the main pipe.

  A tenth invention of the present application is the deaeration device according to any one of the first invention to the ninth invention, wherein the main pipe is located between the first tank and the second tank. A plurality of the horizontal portions connected in parallel with each other, and the deaeration pipe extends upward from each of the plurality of horizontal portions.

  An eleventh invention of the present application is a coating apparatus for applying a liquid to a surface to be processed, and includes a deaeration device according to any one of the first invention to the tenth invention, and a discharge port for discharging a fluid. A nozzle and a supply mechanism for supplying liquid from the second tank to the nozzle.

  A twelfth aspect of the present invention is the coating apparatus according to the eleventh aspect of the present invention, further comprising a stirring and deaeration mechanism that deaerates while stirring the liquid in the second tank.

  A thirteenth aspect of the present application is the coating apparatus according to the eleventh aspect or the twelfth aspect of the present invention, further comprising a foreign matter removing filter provided on the path of the main pipe.

  A fourteenth aspect of the present invention is a deaeration method for removing dissolved gas in a liquid while supplying the liquid from the first tank of the supply source to the second tank of the supply destination through the main pipe, and a) main A step of filling the deaeration pipe with liquid by generating an upward suction force in the deaeration pipe extending upward from the horizontal portion of the pipe; and b) after the step a), in the main pipe Generating a suction force toward the second tank side to form a liquid flow toward the downstream side in the main pipe, and c) bubbles accumulated in the deaeration pipe after the step b) And a step of discharging.

  According to the first to fourteenth inventions of the present application, bubbles generated in the liquid due to the reduced pressure are collected at the upper edge of the main pipe by the flow of the liquid in the main pipe. For this reason, in step b), the bubbles enter the deaeration pipe from the horizontal part of the main pipe. In step c), the air bubbles accumulated in the deaeration pipe are discharged. Thereby, even if it is a case where the viscosity of a liquid is high, the dissolved gas in a liquid can be removed.

  In particular, according to the second invention of the present application, in step b), bubbles accumulated below the third valve of the deaeration pipe are replaced with liquid above the bubbles in the deaeration pipe in step c). Is discharged to the upper side. Thereby, bubbles can be efficiently discharged from the deaeration pipe.

  In particular, according to the third invention of the present application, the air bubbles that have entered the first vertical pipe from the horizontal portion of the main pipe gather in the horizontal pipe and grow into large air bubbles. In step c), the large bubbles are discharged to the outside through the second vertical pipe. Thereby, the quantity of the liquid discharged | emitted with gas can be reduced. That is, only dissolved gas can be efficiently removed from the liquid.

  In particular, according to the fourth invention of the present application, it is possible to grow bubbles more effectively in the horizontal tube.

  In particular, according to the fifth invention of the present application, in step c), the bubbles in the horizontal pipe can be more reliably replaced with the liquid stored in the second pipe.

  In particular, according to the sixth invention of the present application, the gas that has not entered the first deaeration pipe can enter the downstream second deaeration pipe and be discharged to the outside. Thereby, the discharge efficiency of bubbles can be further increased.

  In particular, according to the seventh aspect of the present invention, air bubbles can be discharged more efficiently from the first degassing pipe and the second degassing pipe to the discharge pipe.

  In particular, according to the eighth invention of the present application, the dissolved gas in the liquid stored above the third valve is removed by decompression by opening the fourth valve also in step b). Thereby, the removal efficiency of dissolved gas can further be improved.

  In particular, according to the ninth invention of the present application, the viscosity of the liquid can be reduced. Further, the bubbles can be expanded to increase the efficiency of discharging the bubbles.

  In particular, according to the tenth aspect of the present invention, the amount of liquid supplied to the second tank per unit time can be increased.

  In particular, according to the twelfth aspect of the present invention, bubbles that could not be removed in the deaeration pipe can be removed by the stirring deaeration mechanism.

  In particular, according to the thirteenth aspect of the present invention, it is not necessary to provide a foreign matter removal filter in the supply mechanism between the second tank and the nozzle. Therefore, in the supply mechanism, the pressure loss due to the filter can be reduced.

It is a perspective view of a coating device. It is a perspective view of a slit nozzle. It is the figure which showed the flow path inside a slit nozzle. It is the figure which showed the structure of the supply piping system connected to a slit nozzle. It is the block diagram which showed the connection structure of the control part and each part of a supply piping system. It is the flowchart which showed the flow of the deaeration and supply operation | movement of to-be-coated material. It is the figure which showed notionally the movement of the bubble in deaeration piping. It is the figure which showed the structure of the supply piping system which concerns on a modification. It is the figure which showed the structure of the supply piping system which concerns on a modification. It is the figure which showed the structure of the supply piping system which concerns on a modification.

  Embodiments of the present invention will be described below with reference to the drawings. In the following, for convenience of explanation, the moving direction of the slit nozzle 20 in the coating apparatus 1 is referred to as “front-rear direction”, and the horizontal direction orthogonal to the front-rear direction is referred to as “left-right direction”.

<1. About the configuration of the coating device>
FIG. 1 is a perspective view of a coating apparatus 1 according to an embodiment of the present invention. The coating apparatus 1 is an apparatus that applies a material to be coated, which is a high-viscosity liquid, to the upper surface of a glass carrier substrate 9 in a manufacturing process of a flexible device. As the material to be coated, for example, a molten resin such as polyimide, which is a fluid with high viscosity, is used. The viscosity of the material to be coated is, for example, about several thousand to 10,000 cP. The material to be applied applied to the upper surface of the substrate 9 is then solidified into a thin film. Moreover, a pattern such as an electrode is formed on the surface of the thin film, and a flexible device is formed by peeling the thin film from the substrate 9.

  As shown in FIG. 1, the coating apparatus 1 according to the present embodiment includes a stage 10, a slit nozzle 20, a nozzle holding unit 30, a travel mechanism 40, and a control unit 50.

  The stage 10 is a substantially rectangular parallelepiped holding table on which the substrate 9 is placed and held. The stage 10 is formed of, for example, an integral stone material. The upper surface of the stage 10 is a flat substrate holding surface 11. The substrate holding surface 11 is provided with a number of vacuum suction holes (not shown). When the substrate 9 is placed on the substrate holding surface 11, the lower surface of the substrate 9 is attracted to the substrate holding surface 11 by the suction force of the vacuum suction holes. Thereby, the substrate 9 is fixed in a horizontal posture on the stage 10. A plurality of lift pins are provided inside the stage 10. When unloading the substrate 9 from the stage 10, a plurality of lift pins protrude on the substrate holding surface 11. As a result, the substrate 9 is pulled away from the substrate holding surface 11.

  The slit nozzle 20 is a nozzle that discharges a material to be coated. The slit nozzle 20 has a nozzle body 21 that is long in the left-right direction. A slit-shaped discharge port 23 extending in the left-right direction is provided at the lower end of the nozzle body 21. The discharge port 23 is directed to the upper surface of the substrate 9 placed on the stage 10. When the material to be coated is supplied into the nozzle body 21 from a supply mechanism 70 (see FIG. 4) described later, the material to be coated is directed from the discharge port 23 of the slit nozzle 20 toward the upper surface of the substrate 9 to be processed. Discharged.

  The nozzle holding unit 30 is a mechanism for holding the slit nozzle 20 above the substrate holding surface 11. The nozzle holding part 30 includes a bridging part 31 extending in the left-right direction and a pair of columnar support parts 32 that support both ends of the bridging part 31. The slit nozzle 20 is attached to the lower surface of the bridging portion 31. Each support portion 32 includes an elevating mechanism 33 that adjusts the height of the end portion of the bridging portion 31. When the left / right lifting mechanism 33 is operated, the height and posture of the slit nozzle 20 are adjusted together with the bridging portion 31.

  The traveling mechanism 40 is a mechanism for moving the slit nozzle 20 in the front-rear direction. The travel mechanism 40 includes a pair of travel rails 41 and a pair of linear motors 42. The pair of running rails 41 extend in the front-rear direction near the left and right sides of the stage 10. The traveling rail 41 guides the lower end portion of each support portion 32 in the front-rear direction while supporting the pair of support portions 32. That is, the pair of running rails 41 function as a linear guide that regulates the moving direction of the pair of support portions 32 in the front-rear direction.

  The linear motor 42 includes a stator 421 fixed to the stage 10 and a mover 422 fixed to the support portion 32. The stator 421 extends in the front-rear direction along the left and right side edges of the stage 10. When the coating apparatus 1 is in operation, a magnetic attractive force or a magnetic repulsive force is generated between the stator 421 and the mover 422. Thereby, the movable element 422, the nozzle holding part 30, and the slit nozzle 20 move in the front-rear direction as a unit.

  The controller 50 is a means for controlling the operation of each unit in the coating apparatus 1. As conceptually shown in FIG. 1, the control unit 50 is configured by a computer having an arithmetic processing unit 51 such as a CPU, a memory 52 such as a RAM, and a storage unit 53 such as a hard disk drive. The control unit 50 is electrically connected to each part in the coating apparatus 1 such as the lift pin, the lifting mechanism 33, and the linear motor 42 described above. The control unit 50 is also electrically connected to valves and pumps provided in a deaeration device 60 and a supply mechanism 70 described later. The control unit 50 temporarily reads the computer program and data stored in the storage unit 53 into the memory 52, and the calculation processing unit 51 performs calculation processing based on the computer program and data, whereby the coating apparatus 1 is processed. The operation of each part is controlled. Thereby, the coating process with respect to the board | substrate 9 advances.

<2. Structure of slit nozzle>
Next, a more detailed structure of the slit nozzle 20 will be described. FIG. 2 is a perspective view of the slit nozzle 20. FIG. 3 is a view showing the flow path 210 inside the slit nozzle 20.

  As shown in FIG. 2, the nozzle body 21 of the slit nozzle 20 includes a pair of nozzle members 211 and 212 and a pair of side plates 213 and 214. As a material of the nozzle members 211 and 212 and the side plates 213 and 214, for example, a metal such as aluminum is used. When the pair of nozzle members 211 and 212 are fixed to each other and the pair of side plates 213 and 214 are attached to the left and right ends thereof, the nozzle body 21 having the flow path 210 therein is formed.

  The nozzle body 21 is provided with a pair of supply ports 22 and one slit-like discharge port 23. The pair of supply ports 22 are provided in the pair of side plates 213 and 214, respectively. One discharge port 23 opens in a slit shape between the lower end portion of the front nozzle member 211 and the lower end portion of the rear nozzle member 212. When the coating apparatus 1 is in operation, the material to be coated is supplied from the pair of supply ports 22 to the flow path 210 in the nozzle body 21. Then, the material to be coated in the flow path 210 is discharged from the discharge port 23 toward the lower side of the nozzle body 21.

  Further, as shown in FIG. 2, the nozzle body 21 of the present embodiment has one discharge port 24. The discharge port 24 is provided on the upper surface of the nozzle body 21. Bubbles that could not be removed by the deaeration device 60 described later are discharged from the discharge port 24 to the outside of the slit nozzle 20 together with the rinse liquid when the slit nozzle 20 is cleaned.

<3. About the configuration of the supply piping system>
Then, the structure of the supply piping system which supplies a to-be-coated material to the slit nozzle 20 is demonstrated. FIG. 4 is a diagram showing the configuration of the supply piping system connected to the slit nozzle 20. As shown in FIG. 4, the supply piping system of this embodiment includes a deaeration device 60 and a supply mechanism 70.

  The deaeration device 60 is provided on the upstream side of the piping system from the supply mechanism 70. The deaeration device 60 removes dissolved gas in the material to be coated L while supplying the material to be coated L from the first tank 81 as the supply source to the second tank 82 as the supply destination. As shown in FIG. 4, the deaeration device 60 of this embodiment includes a main pipe 61, a deaeration pipe 62, a drain tank 63, and a decompression unit 64.

  The main pipe 61 is a pipe that connects the first tank 81 and the second tank 82. The first tank 81 stores an unused material L to be applied or a material L to be applied that has been regenerated after being used once. The material L to be coated stored in the first tank 81 is supplied to the second tank 82 through the main pipe 61. Further, as shown in FIG. 4, the main pipe 61 has a horizontal portion 611 extending in a substantially horizontal direction (a direction substantially perpendicular to the direction of gravity).

  The horizontal portion 611 of the main pipe 61 is provided with a foreign substance removal filter 83, a first valve 91, and a second valve 92. When foreign material is contained in the material L to be applied supplied from the first tank 81, the foreign material is removed by the foreign material removal filter 83. The first valve 91 and the second valve 92 are electromagnetic valves that perform an opening / closing operation based on an electric signal from the control unit 50. The first valve 91 is provided at a position on the upstream side (first tank 81 side) with respect to the connection portion with the deaeration pipe 62 on the path of the main pipe 61. The second valve 92 is provided at a position on the downstream side (second tank 82 side) with respect to the connection portion with the deaeration pipe 62 on the path of the main pipe 61.

  The deaeration pipe 62 is a pipe for collecting bubbles contained in the material L to be applied flowing through the main pipe 61. As shown in FIG. 4, the deaeration pipe 62 of the present embodiment has a first vertical pipe 621, a horizontal pipe 622, a second vertical pipe 623, and a discharge pipe 624. The first vertical pipe 621 extends upward from the horizontal portion 611 of the main pipe 61. The horizontal pipe 622 extends horizontally from the upper end of the first vertical pipe 621. The second vertical tube 621 extends further upward from the other end of the horizontal tube 622. The discharge pipe 624 connects the upper end portion of the second vertical pipe 623 and the drain tank 63.

  The deaeration pipe 62 is provided with a third valve 93, a fourth valve 94, a first sensor 84, and a second sensor 85. The third valve 93 and the fourth valve 94 are electromagnetic valves that perform an opening / closing operation based on an electric signal from the control unit 50. The third valve 93 is inserted on the path of the second vertical pipe 621. The fourth valve 94 is inserted on the path of the discharge pipe 624. The first sensor 84 is provided at a position above the third valve 93 on the path of the second vertical pipe 623. The first sensor 84 detects the presence / absence of the material to be coated L at the position of the second vertical tube 623 and transmits an electric signal indicating the detection result to the control unit 50. The second sensor 85 is provided in the vicinity of the horizontal tube 622. The second sensor 85 detects whether or not bubbles are accumulated in the horizontal tube 622 in a deaeration process described later, and transmits an electric signal indicating the detection result to the control unit 50. For the first sensor 84 and the second sensor 85, for example, optical sensors are used.

  The drain tank 63 is provided in order to prevent the coating material L sucked into the deaeration pipe 62 from flowing into the vacuum pump 640 described later. Even if the material to be coated L excessively flows into the deaeration pipe 62, the material to be coated L is collected in the drain tank 63 and does not flow into the vacuum pump 640 side. The material L to be applied collected in the drain tank 63 is discharged from the lower part of the drain tank 63 and is discarded or regenerated.

  The decompression unit 64 includes a vacuum pump 640, a first suction pipe 641, and a second suction pipe 642. Both ends of the first suction pipe 641 are connected to the vacuum pump 640 and the drain tank 63, respectively. Both ends of the second suction pipe 642 are connected to the vacuum pump 640 and the second tank 82, respectively. Therefore, when the vacuum pump 640 is operated, the air in the first suction pipe 641 and the drain tank 63 is sucked to the vacuum pump 640 side, and the air in the second suction pipe 642 and the second tank 82 is also Suction to the vacuum pump 640 side. Thereby, the inside of the main piping 61 and the deaeration piping 62 is depressurized and becomes negative pressure. Further, a suction force toward the second tank 82 side is generated in the main pipe 61, and a suction force toward the drain tank 63 side is generated in the deaeration pipe 62.

  Further, as shown in FIG. 4, in this embodiment, a stirrer 86 is provided in the second tank 82. The stirrer 86 is rotated by power obtained from a motor (not shown). Thereby, the material L to be coated stored in the second tank 82 is agitated. When the coating material L stored in the second tank 82 contains bubbles that could not be collected by the deaeration pipe 62 described above, the bubbles are removed when the stirrer 86 is operated. It is possible to float on the liquid level of L.

  The supply mechanism 70 is a mechanism for supplying the material to be coated L from the second tank 82 to the slit nozzle 20. The supply mechanism 70 includes a liquid supply pipe 71 and a liquid supply pump 72. The upstream end of the liquid feeding pipe 71 is connected to the bottom of the second tank 82. The downstream end of the liquid feeding pipe 71 branches in two directions and is connected to the two supply ports 22 of the slit nozzle 20 respectively. When the liquid feed pump 72 is operated, the coating material L stored in the second tank 82 is supplied to the slit nozzle 20 through the liquid feed pipe 71 at a pressure generated by the liquid feed pump 72. Then, the material to be coated L is discharged from the discharge port 23 of the slit nozzle 20 onto the upper surface of the substrate 9.

  FIG. 5 is a block diagram showing a connection configuration between the control unit 50 and each part of the supply piping system. As shown in FIG. 5, the controller 50 includes the first valve 91, the second valve 92, the third valve 93, the fourth valve 94, the first sensor 84, the second sensor 85, the agitator 86, and the vacuum pump described above. 640 and the liquid feed pump 72 are electrically connected to each other. The control unit 50 controls the operation of these units based on a preset computer program or an external instruction. Thereby, each operation | movement of deaeration and supply of the to-be-coated material L advances.

<4. Degassing and supplying operation of coated material>
Next, an operation when supplying the material L to be applied stored in the first tank to the slit nozzle 20 while degassing in the coating apparatus 1 will be described. FIG. 6 is a flowchart showing the flow of the operation. FIG. 7 is a diagram conceptually showing the movement of bubbles in the deaeration pipe 62.

  As shown in FIG. 6, the coating apparatus 1 first closes the second valve 92 and opens the first valve 91, the third valve 93, and the fourth valve 94. Then, the operation of the vacuum pump 640 is started. Then, an upward suction force is generated in the deaeration pipe 62 due to the pressure of the vacuum pump 640. Therefore, the material to be coated L supplied from the first tank 81 flows into the deaeration pipe 62 through the main pipe 61. As a result, the portion upstream of the second valve 92 of the main pipe 61 and the portion of the deaeration pipe 62 at least below the third valve 93 are filled with the material to be coated L (step S1).

  When the material to be coated L reaches the detection position of the first sensor 84, the first sensor 84 transmits a detection signal indicating that the material to be coated L has been detected to the control unit 50. When receiving the detection signal, the controller 50 closes the third valve 93 and opens the second valve 92. Then, a suction force toward the second tank 82 is generated in the main pipe 61 by the pressure transmitted from the vacuum pump 640 through the second suction pipe 642 and the second tank 82. Accordingly, a flow of the material to be coated L is formed in the main pipe 61 from the first tank 81 toward the second tank 82 (step S2).

  At this time, the inside of the main pipe 61 and the deaeration pipe 62 is in a state (negative pressure state) where the pressure is lower than the atmospheric pressure due to the suction force of the vacuum pump 640. For this reason, the dissolved gas in the coating material L that has flowed out of the first tank 81 is generated in the coating material L as bubbles. Further, since the material to be coated L is flowing inside the main pipe 61, the flow of the bubbles is promoted by the flow. Therefore, as indicated by a broken line B1 in FIG. 7, bubbles in the material to be coated L gather at the upper edge of the main pipe 61. Then, the air bubbles gathered at the upper edge of the main pipe 61 efficiently enter the first vertical pipe 621 from the main pipe 61 as indicated by a broken line arrow A1 in FIG. In this way, even if the viscosity of the material to be coated L is high, the bubbles in the material to be coated L can efficiently enter the deaeration pipe 62. Therefore, it is possible to significantly reduce the time required for removing bubbles, compared with the case where only the stirrer 86 in the second tank 82 is used.

  The bubbles that have entered the first vertical tube 621 then rise to the height of the horizontal tube 622. Then, as indicated by a broken line B2 in FIG. 7, bubbles are accumulated along the lower surface of the upper edge portion of the horizontal tube 622. Further, at the position of the broken line B2, the plurality of bubbles gather together and grow into a large bubble.

  When the bubble grows and a predetermined area in the horizontal tube 622 is occupied by the bubble, the second sensor 85 detects the bubble and transmits a detection signal to the control unit 50. When receiving the detection signal, the control unit 50 closes the first valve 91 and the second valve 92 and opens the third valve 93. If it does so, the to-be-coated material L stored in the 2nd vertical pipe 623 will move to the horizontal pipe 622 side like the broken-line arrow A2 in FIG. 7 with the dead weight. Thereby, the air bubbles in the horizontal tube 622 move to the second vertical tube 623 side as indicated by a broken line arrow A3. That is, the material L to be coated in the second vertical tube 623 and the bubbles in the horizontal tube 622 are replaced. As a result, the bubbles in the horizontal tube 622 are discharged above the liquid surface of the material L to be coated in the second vertical tube 623 (step S3). The gas constituting the bubbles is then discharged from the vacuum pump 640 to the outside through the discharge pipe 624, the drain tank 63, and the first suction pipe 641.

  Thus, in this embodiment, bubbles are grown in the horizontal tube 622 of the deaeration pipe 62, and large bubbles after the growth are discharged. If it does in this way, the quantity of to-be-coated material L discharged | emitted with gas can be reduced. Therefore, only the dissolved gas can be efficiently removed from the material to be coated L.

  Moreover, in said step S3, the bubble grown in the horizontal tube 622 is discharged | emitted upwards by substituting the to-be-coated material L in the 2nd vertical tube 623. FIG. If it does in this way, a bubble can be efficiently levitated to the liquid level of the material L to be coated. In addition, it is preferable that the 2nd vertical pipe 623 has the volume more than the horizontal pipe 622. Then, in step S <b> 3, the bubbles in the horizontal tube 622 can be more reliably replaced with the material to be coated L in the second vertical tube 623.

  In the present embodiment, the fourth valve 94 is opened from step S1 to step S3. That is, the fourth valve 94 is opened even in step S2 in which the third valve 93 is closed. For this reason, in step S2, bubbles are generated from the material to be coated L stored above the third valve 93 in the second vertical pipe 623, and the bubbles rise to the liquid level, thereby forming the bubbles. Gas is removed. Thereby, the removal efficiency of dissolved gas can further be improved.

  In addition, when bubbles are not sufficiently removed only by the deaeration pipe 62, the stirrer 86 in the second tank 82 may be rotated by a command from the control unit 50. Then, bubbles remaining in the material to be coated L can float to the liquid surface in the second tank 82. At the same time, if the vacuum pump 640 is operated, the gas constituting the bubbles can be discharged from the vacuum pump 640 to the outside through the second tank 82 and the second suction pipe 642. That is, in the present embodiment, the stirrer 86 and the vacuum pump 640 constitute a stirring and deaeration mechanism that deaerates the material L to be coated in the second tank 82 while stirring. Thus, if a stirring deaeration mechanism is used in combination, the bubble removal rate can be further increased.

  Thereafter, the control unit 50 operates the liquid feed pump 72. When it does so, the to-be-coated material L stored in the 2nd tank 82 will be supplied to the slit nozzle 20 through the liquid feeding piping 71 (step S4). Then, the material to be coated L supplied to the slit nozzle 20 is discharged from the discharge port 23 of the slit nozzle 20 onto the upper surface of the substrate 9.

  In the present embodiment, the foreign matter removal filter 83 is provided in the main pipe 61 that connects the first tank 81 and the second tank 82. And the foreign material removal filter was excluded from the liquid feeding piping 71 which connected the 2nd tank 82 and the slit nozzle 20. FIG. By so doing, pressure loss due to the foreign matter removal filter is eliminated when the material to be coated L is supplied in step S4. Therefore, the material L to be coated can be supplied to the slit nozzle 20 with a smaller pressure.

<5. Modification>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

  FIG. 8 is a diagram illustrating a configuration of a supply piping system according to a modification. In the example of FIG. 8, a first deaeration pipe 62 </ b> A and a second deaeration pipe 62 </ b> B are provided in the deaeration device 60. Both the first deaeration pipe 62A and the second deaeration pipe 62B extend upward from the horizontal portion 611. Further, the lower end portion of the second degassing pipe 62B is located on the downstream side of the main pipe 61 with respect to the lower end portion of the first degassing pipe 62A. The first valve 91 is provided on the upstream side of the connection portion with the first deaeration pipe 62 </ b> A on the main pipe 61. The second valve 92 is provided on the downstream side of the connection portion with the second deaeration pipe 62 </ b> B on the path of the main pipe 61. The third valve 93 is provided on each path of the first deaeration pipe 62A and the second deaeration pipe 62B.

  Thus, if the two degassing pipes 62A and 62B are provided, the gas that has not entered the first degassing pipe 62A enters the second degassing pipe 62B on the downstream side and is discharged to the outside. be able to. Therefore, the bubble discharge efficiency can be further increased.

  In particular, in the example of FIG. 8, the upper end portion of the first degassing pipe 62A and the upper end portion of the second degassing pipe 62B are connected to one discharge pipe 624 by an inclined pipe 625 extending obliquely upward. Has been. By so doing, it is possible to smoothly discharge bubbles from the first degassing pipe 62A and the second degassing pipe 62B to the discharge pipe 624 without resisting gravity. In particular, when the process equivalent to step S2 described above is performed, the bubbles in the material to be coated L stored above the closed third valve 93 can be easily lifted upward.

  In addition, in order to further improve the discharge efficiency of bubbles, the number of the deaeration pipes 62 may be three or more.

  FIG. 9 is a diagram illustrating a configuration of a supply piping system according to another modification. In the example of FIG. 9, a heater 87 is provided in a part of the main pipe. The heater 87 is electrically connected to the control unit 50. When the heater 87 is operated by a command from the control unit 50, the material to be coated L in the main pipe 61 is heated. Thereby, the viscosity of the to-be-coated material L can be reduced. Further, bubbles in the material to be coated L expand. For this reason, the bubbles are more likely to enter the deaeration pipe 62, and the bubbles are more likely to rise in the deaeration pipe 62. Thereby, the bubble discharge efficiency can be further increased.

  FIG. 10 is a diagram illustrating a configuration of a supply piping system according to another modification. In the example of FIG. 10, the main pipe 61 has two horizontal portions 611. The two horizontal portions 611 are connected in parallel between the first tank 81 and the second tank 82. A deaeration pipe 62 extends upward from each horizontal part 611. In this way, the coating material L can be supplied to the second tank 82 simultaneously or alternately by the two horizontal portions 611. Therefore, the supply amount of liquid to the second tank 82 per unit time can be increased.

  In the above embodiment, the horizontal tube 622 is disposed horizontally. However, the posture of the horizontal tube 622 is not necessarily horizontal. The horizontal tube 622 may be a tube that extends laterally from the upper end of the first vertical tube 621 at an angle closer to the horizontal than the first vertical tube 621. However, the end of the horizontal tube 622 on the second vertical tube 623 side is preferably the same height as or higher than the end of the horizontal tube 622 on the first vertical tube 621 side. In order to grow bubbles more effectively in the horizontal tube 622, the angle of the horizontal tube 622 with respect to the horizontal plane is preferably 0 ° or more and 45 ° or less.

  In the above embodiment, the first vertical pipe 621, the horizontal pipe 622, and the second vertical pipe 623 are all pipes having the same diameter. However, the inner diameters of the first vertical tube 621, the horizontal tube 622, and the second vertical tube 623 are not necessarily the same. For example, in order to increase the amount of the material to be coated L stored above the third valve 93 in step S2, the inner diameter of the second vertical tube 623 is set to be larger than the inner diameters of the first vertical tube 621 and the horizontal tube 622. You can make it bigger.

  In the apparatus of the above embodiment, the material to be coated L is transported only by the pressures of the vacuum pump 640 and the liquid feed pump 72. However, in parallel with the driving of these pumps, a pressurized gas may be introduced into the first tank 81 and the second tank 82 to promote the flow of the material to be coated L.

  Moreover, although said coating device 1 was used for the process which manufactures the base material itself of a flexible device, the coating device of this invention forms a protective film on the surface of the base material after device formation. It may be used in a process. Moreover, the coating device of this invention may be used for the process of apply | coating the adhesive agent at the time of bonding a board | substrate and a board | substrate. Moreover, the coating apparatus of this invention may be used for the manufacturing process of liquid crystal display devices other than a flexible device, or a semiconductor substrate. Moreover, the coating device of this invention may be used for the manufacturing process of batteries, such as a lithium ion secondary battery and a fuel cell. That is, the coating apparatus of the present invention is particularly suitable for a process for coating a material with high viscosity.

  Further, the details of the deaeration device and the coating device may be different from the configurations shown in the drawings of the present application. Moreover, you may combine suitably each element which appeared in said embodiment and modification in the range which does not produce inconsistency.

DESCRIPTION OF SYMBOLS 1 Coating device 9 Substrate 10 Stage 11 Substrate holding surface 20 Slit nozzle 21 Nozzle body 22 Supply port 23 Discharge port 24 Discharge port 30 Nozzle holding part 31 Bridging part 32 Support part 33 Lifting mechanism 40 Traveling mechanism 41 Traveling rail 42 Linear motor 50 Control Portion 60 Deaerator 61 Main piping 62, 62A, 62B Deaeration piping 63 Drain tank 64 Depressurization unit 70 Supply mechanism 71 Liquid supply piping 72 Liquid supply pump 81 First tank 82 Second tank 83 Foreign matter removal filter 84 First sensor 85 Second sensor 86 Stirrer 87 Heater 91 First valve 92 Second valve 93 Third valve 94 Fourth valve 611 Horizontal portion 621 First vertical pipe 622 Horizontal pipe 623 Second vertical pipe 624 Discharge pipe 625 Inclined pipe 640 Vacuum pump 641 First suction pipe 642 Second suction pipe L Material to be coated

Claims (14)

A degassing device for removing dissolved gas in a liquid,
A main pipe having a horizontal portion extending substantially horizontally, connecting the first tank of the supply source and the second tank of the supply destination;
A deaeration pipe extending upward from the horizontal part;
A plurality of valves provided in the main pipe and the deaeration pipe;
A decompression unit that generates a suction force toward the second tank in the main pipe, and generates a suction force upward in the deaeration pipe;
A control unit for controlling the plurality of valves and the pressure reducing unit;
With
The control unit controls the pressure reducing unit and the plurality of valves,
a) filling the deaeration pipe with liquid;
b) after the step a), forming a liquid flow toward the downstream side in the main pipe;
c) a step of discharging bubbles accumulated in the deaeration pipe after the step b);
Realizing deaeration device. The deaerator according to claim 1,
The plurality of valves are:
A first valve provided on the upstream side of the connection with the deaeration pipe on the path of the main pipe;
A second valve provided on the downstream side of the connection with the deaeration pipe on the path of the main pipe;
A third valve provided on the path of the deaeration pipe;
Including
The controller is
In step a), closing the second valve and opening the first valve and the third valve;
In step b), closing the third valve and opening the second valve;
In the step c), the deaeration device discharges the bubbles accumulated below the third valve of the deaeration pipe upward by opening the third valve. The deaeration device according to claim 2,
The deaeration pipe is
A first vertical pipe extending upward from the horizontal portion;
A horizontal tube extending laterally from the upper end of the first vertical tube at an angle closer to the horizontal than the first vertical tube;
A second vertical pipe extending upward from the other end of the horizontal pipe;
Including
A deaeration device in which the second valve is provided in the second vertical pipe. The deaeration device according to claim 3,
The end of the horizontal tube on the second vertical tube side is equal to or higher than the end of the horizontal tube on the first vertical tube side,
The deaeration device in which an angle of the horizontal tube with respect to a horizontal plane is 0 ° or more and 45 ° or less. A deaeration device according to claim 3 or claim 4, wherein
The second vertical pipe is a deaeration device having a volume larger than that of the horizontal pipe. A deaeration device according to any one of claims 2 to 5,
The deaeration pipe is at least
A first deaeration pipe extending upward from the horizontal part;
A second deaeration pipe extending upward from a position downstream of the first deaeration pipe of the horizontal portion;
Including
The first valve is provided on an upstream side of a connection portion with the first deaeration pipe on the path of the main pipe,
The second valve is provided on the downstream side of the connection portion with the second deaeration pipe on the path of the main pipe,
The third valve is a deaeration device provided on each path of the first deaeration pipe and the second deaeration pipe. The deaeration device according to claim 6,
A deaeration device in which an upper end portion of the first deaeration pipe and an upper end portion of the second deaeration pipe are connected to one discharge pipe by an inclined pipe extending obliquely upward. A deaeration device according to any one of claims 2 to 7,
A fourth valve provided between the deaeration pipe and the pressure reducing unit;
A deaeration device in which the fourth valve is opened from step a) to step c). A deaeration device according to any one of claims 1 to 8,
A deaeration device further comprising a heater for heating the liquid in the main pipe. A deaeration device according to any one of claims 1 to 9,
The main pipe includes a plurality of the horizontal portions connected in parallel between the first tank and the second tank,
The deaeration device in which the deaeration pipe extends upward from each of the plurality of horizontal parts. An application device for applying a liquid to a surface to be processed,
A deaeration device according to any one of claims 1 to 10,
A nozzle having a discharge port for discharging a fluid;
A supply mechanism for supplying liquid from the second tank to the nozzle;
A coating apparatus comprising: It is a coating device of Claim 11, Comprising:
A coating apparatus further comprising an agitation deaeration mechanism for deaeration while stirring the liquid in the second tank. The coating apparatus according to claim 11 or 12,
A coating apparatus further comprising a foreign matter removal filter provided on a path of the main pipe. A degassing method for removing dissolved gas in the liquid while supplying the liquid from the first tank of the supply source to the second tank of the supply destination via the main pipe,
a) filling the deaeration pipe with a liquid by generating an upward suction force in the deaeration pipe extending upward from the horizontal portion of the main pipe;
b) After the step a), by generating a suction force toward the second tank in the main pipe, forming a liquid flow toward the downstream side in the main pipe;
c) a step of discharging bubbles accumulated in the deaeration pipe after the step b);
A degassing method.

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