CN110899051B

CN110899051B - Feeding device, coating device and feeding method

Info

Publication number: CN110899051B
Application number: CN201910525682.0A
Authority: CN
Inventors: 芳川典生; 水野博喜; 瀬川邦彦; 伊藤隆介; 后藤顺一
Original assignee: Screen Holdings Co Ltd
Current assignee: Screen Holdings Co Ltd
Priority date: 2018-09-14
Filing date: 2019-06-18
Publication date: 2022-02-11
Anticipated expiration: 2039-06-18
Also published as: JP6808696B2; TWI741316B; TW202010576A; CN110899051A; JP2020044465A

Abstract

The invention provides a supply device capable of efficiently removing dissolved gas in a liquid with high viscosity, a coating device comprising the supply device, and a supply method. The supply device (30) is a supply device for supplying a high-viscosity treatment liquid to a supply target (22). The supply device (30) includes a liquid supply pipe (32) that connects a tank (31) for storing the processing liquid and the supply port (320) in a flow path, and a main pump (33), a degassing unit (34), an auxiliary pump (35), and a filter (36) that are inserted in the liquid supply pipe in this order from the downstream side. The auxiliary pump (35) pressurizes the processing liquid toward the degassing unit on the upstream side of the degassing unit (34). The degassing unit has a plurality of hollow fiber membranes housed inside the casing, and a decompression mechanism for decompressing the space outside the hollow fiber membranes. This enables the dissolved gas in the treatment liquid having a high viscosity to be efficiently removed, and the apparatus to be downsized.

Description

Feeding device, coating device and feeding method

Technical Field

The present invention relates to a supply device that supplies a high-viscosity liquid to a supply target, an application device including the supply device, and a supply method of supplying a high-viscosity liquid.

Background

In a manufacturing process of a glass substrate for a liquid crystal Display device, a semiconductor substrate, a glass substrate for a Plasma Display Panel (PDP), a glass substrate for a photomask (photo mask), a substrate for a color filter (color filter), a substrate for a recording disk (disk), a substrate for a solar cell, a substrate for a precision electronic device such as a substrate for electronic paper (paper), a rectangular glass substrate, a flexible (flexible) substrate for a thin film liquid crystal, a substrate for an organic Electroluminescence (EL) (hereinafter, simply referred to as "substrate"), a coating apparatus for coating a liquid such as a photoresist (photoresist) on a surface of a substrate has been used. A conventional coating apparatus is described in, for example, patent document 1. The coating apparatus of patent document 1 ejects a coating liquid from a slit die (slit die) having a slit-shaped ejection port onto a substrate held by suction by a stage (stage) that is movable in a horizontal direction.

[ Prior art documents ]

[ patent document ]

[ patent document 1] Japanese patent laid-open No. 2017-23990

Disclosure of Invention

[ problems to be solved by the invention ]

In such a coating apparatus, if a dissolved gas is present in the liquid, so-called "bubbling" is likely to occur in the slit nozzle. If "bubbling" occurs, the liquid may not be uniformly applied from the ejection port, and the uniformity of the coating film may be reduced. Therefore, a degassing treatment for removing dissolved gas from the liquid before coating has been conventionally performed. In a conventional coating apparatus, a tank for degassing, in which a liquid before coating is stored, is set to a negative pressure, thereby bubbling a dissolved gas in the liquid. When the liquid has a low viscosity, bubbles generated in the liquid can be easily floated up to the liquid surface and discharged to the outside of the container.

However, when a high-viscosity liquid is used, it takes a very long time for bubbles to float up to the liquid surface. In particular, the finer the bubbles, the more difficult the bubbles float. Therefore, when the liquid consumption rate is high, such as when the coating process is continuously performed, the number of degassing grooves must be increased. As a result, the size of the entire apparatus becomes large. In recent years, in the production process of flexible elements or batteries, there has been an increasing demand for apparatuses for applying a high-viscosity liquid to a surface to be treated. Accordingly, there is a demand for a technique capable of efficiently removing dissolved gas from a high-viscosity liquid without increasing the size of the apparatus.

The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a supply device capable of efficiently removing dissolved gas in a liquid having a high viscosity, an application device including the supply device, and a supply method.

[ means for solving problems ]

In order to solve the problem, a first invention of the present application is a supply device for supplying a high-viscosity treatment liquid to a supply target, the supply device including: a tank for storing the treatment solution; a supply port that supplies the processing liquid to the supply target; a liquid feeding pipe connecting the tank and the supply port via a flow path; a main pump (main pump) interposed in the liquid supply pipe and configured to supply the processing liquid from the tank to the supply port; a degassing unit interposed in the liquid supply pipe on an upstream side of the main pump; an auxiliary pump (assist pump) inserted in the liquid feed pipe upstream of the degassing unit and configured to pressurize the treatment liquid toward the degassing unit; and a filter interposed in the liquid feeding pipe on an upstream side of the degassing unit, the degassing unit including: a cylindrical case (casting); a plurality of hollow fiber membranes housed inside the housing; and a decompression mechanism configured to decompress the space inside the housing and outside the hollow fiber membrane.

A second invention of the present application is the supply device according to the first invention, wherein the auxiliary pump includes: a fluid reservoir capable of increasing or decreasing the internal volume; and a collapsible tube that constitutes a flow path and is disposed inside the fluid reservoir chamber, wherein when the volume of the fluid reservoir chamber is reduced, the pressure applied to the outer peripheral surface of the tube is increased, and the volume of the tube is reduced, thereby discharging the processing liquid from the tube.

A third invention of the present application is the feeding apparatus according to the second invention, wherein the auxiliary pump is a Coaxial tube pump (CT).

A fourth aspect of the present invention is the supply apparatus according to any one of the first to third aspects, wherein the processing liquid is varnish containing a polyimide precursor, and the supply target is a nozzle that ejects the varnish.

A fifth aspect of the present invention is a coating apparatus that coats a surface to be treated with a liquid, the coating apparatus including: the supply device according to any one of the first to fourth inventions; and a nozzle which is the supply target of the supply device and has an ejection port for ejecting the processing liquid.

A sixth invention of the present application is the coating apparatus according to the fifth invention, further comprising: and a frame body having a stage on an upper surface thereof, the stage being configured to mount a substrate to be processed, the nozzle being movably disposed above the stage, the main pump and the degassing unit being housed in the frame body.

A seventh invention of the present application is a supply method for supplying a high-viscosity treatment liquid to a supply target, the supply method including the steps of: a) pressurizing and supplying the treatment liquid from a tank storing the treatment liquid toward a degassing unit by an auxiliary pump; b) in the degassing unit, the treatment liquid passes through the plurality of hollow fiber membranes whose outside spaces are depressurized, thereby removing dissolved gas in the treatment liquid; and c) delivering the treatment liquid through the degassing unit by a main pump.

[ Effect of the invention ]

According to the first to seventh aspects of the present invention, the dissolved gas in the treatment liquid having a high viscosity can be efficiently removed, and the apparatus can be downsized.

In particular, according to the second and third aspects of the present invention, the phenomenon that particles (particles) are generated in the auxiliary pump and mixed into the treatment liquid can be suppressed.

In particular, according to the sixth invention of the present application, the degassing unit is disposed in the immediate vicinity of the nozzle, so that the processing liquid subjected to the degassing treatment can be supplied to the nozzle before the gas is again absorbed.

Drawings

Fig. 1 is a schematic view of a coating apparatus.

Fig. 2 is a perspective view of the coating portion.

FIG. 3 is a sectional view showing the structure of the degassing unit.

Fig. 4 is a sectional view showing the structure of the assist pump.

Fig. 5 is a sectional view showing the structure of the assist pump.

Fig. 6 is a sectional view showing another example of the structure of the assist pump.

Fig. 7 is a flowchart showing the flow of each step performed on the treatment liquid in the coating apparatus.

[ description of symbols ]

1: coating device

9: substrate (carrier substrate)

10: control unit

11: arithmetic processing unit

12: memory device

13: storage unit

20: coating section

21: frame body

22: slit nozzle

23: nozzle holding part

24: traveling mechanism

30: supply part

31: supply tank

32: liquid delivery pipe

33: main pump

34: degassing unit

35. 35A: auxiliary pump

36: filter

41: shell body

42: hollow fiber membrane

43: pressure reducing mechanism

50: frame body

51: lower check valve

52: upper check valve

53. 53A: pipe

54: fluid retaining part

55A: drive shaft

61A: functional part

62A: shaft arrangement part

63A: connecting part

210: carrying platform

221: nozzle body

223: discharge port

231: bridge part

232: supporting part

233: lifting mechanism

241: walking rail

242: linear motor

242 a: stator

242 b: mover

311: supply pipe

320: supply port

411. 501, 501A: inlet port

412. 502, 502A: outflow opening

413: exhaust port

431: pressure reducing pipe

432: pressure reducing pump

500: flow path

540. 540A: fluid reservoir

541: small diameter corrugated pipe

542: large-diameter corrugated pipe

543: center of corrugated pipe

544: moving mechanism

S101 to S105: step (ii) of

Detailed Description

Embodiments of the present invention will be described below with reference to the drawings.

< 1. Structure relating to coating apparatus >

Fig. 1 is a schematic view of a coating apparatus 1 according to an embodiment of the present invention. The coating apparatus 1 is an apparatus for coating a treatment liquid (coating material) as a high viscosity liquid on an upper surface of a carrier substrate 9 made of glass (hereinafter referred to as "substrate 9") in a manufacturing process of a flexible device. The treatment liquid coated on the upper surface of the substrate 9 is then cured into a thin film. Then, a pattern (pattern) of electrodes and the like is formed on the surface of the thin film, and the thin film is peeled from the substrate 9, thereby forming a flexible element.

For the treatment liquid, for example, a molten resin containing a polyimide precursor as a fluid having a high viscosity is used. The viscosity of the treatment liquid is, for example, about thousands cP to ten thousand cP. Hereinafter, the "high viscosity" means thousands cP or more.

As shown in fig. 1, the coating apparatus 1 includes a coating section 20, a supply section 30 for supplying a treatment liquid to the coating section 20, and a control section 10.

The coating section 20 is configured to coat the substrate 9 with the treatment liquid supplied from the supply section 30. Fig. 2 is a perspective view of the coating portion 20. Hereinafter, for convenience of explanation, the moving direction of the slit nozzle 22 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".

As shown in fig. 2, the coating section 20 of the present embodiment includes a frame 21, a slit nozzle 22, a nozzle holding section 23, and a traveling mechanism 24.

The housing 21 has a stage 210 on which the substrate 9 is placed and held. A part of the supply unit 30 is housed in the housing 21. The top surface of the stage 210 is flat and has a plurality of vacuum suction holes (not shown). When the substrate 9 is placed on the stage 210, the lower surface of the substrate 9 is attracted to the upper surface of the stage 210 by the suction force of the vacuum suction holes. Thereby, the substrate 9 is fixed to the stage 210 in a horizontal posture. Further, inside the stage 210, a plurality of lift pins (lift pins) are provided. When the substrate 9 is carried out from the stage 210, the plurality of lift pins protrude onto the stage 210. Thereby, the substrate 9 is separated from the upper surface of the stage 210.

The slit nozzle 22 is a nozzle for discharging the treatment liquid. The slit nozzle 22 has a nozzle body (nozzle body)221 that is long in the left-right direction. A slit-shaped discharge port 223 extending in the left-right direction is provided at the lower end portion of the nozzle main body 221. The ejection port 223 faces the upper surface of the substrate 9 mounted on the stage 210. When the processing liquid is supplied from the supply portion 30 into the nozzle main body 221, the processing liquid is discharged from the discharge port 223 of the slit nozzle 22 toward the upper surface of the substrate 9 to be processed.

The nozzle holding portion 23 is a mechanism for holding the slit nozzle 22 above the stage 210. The nozzle holding portion 23 includes: a bridge 231 extending in the left-right direction; and a pair of columnar supports 232 supporting both ends of the bridge 231. The slit nozzle 22 is attached to the lower surface of the bridge 231. Each support portion 232 includes an elevating mechanism 233 for adjusting the height of the end portion of the bridge 231. When the left and right elevating mechanisms 233 are operated, the height and posture of the slit nozzle 22 are adjusted together with the bridge 231.

The traveling mechanism 24 is a mechanism for moving the slit nozzle 22 in the front-rear direction. The traveling mechanism 24 has a pair of traveling rails (rails) 241 and a pair of linear motors (linear motors) 242. The pair of traveling rails 241 extend in the front-rear direction on the left and right side portions of the stage 210. The traveling rail 241 guides the lower end of each support 232 in the front-rear direction while supporting the pair of supports 232. That is, the pair of running rails 241 function as linear guides (linear guides) that regulate the moving direction of the pair of supporting portions 232 in the front-rear direction.

The linear motor 242 includes a stator 242a fixed to the stage 210 and a mover 242b fixed to the support portion 232. The stators 242a extend in the front-rear direction along the left and right side edges of the stage 210. During operation of the coating portion 20, a magnetic attraction force or a magnetic repulsion force is generated between the stator 242a and the mover 242 b. Thereby, the mover 242b, the nozzle holding portion 23, and the slit nozzle 22 move in the front-rear direction as a unit.

The supply unit 30 includes a supply tank 31, a liquid supply pipe 32, a main pump 33, a degassing unit 34, an auxiliary pump 35, and a filter 36. The supply section 30 is a supply device for supplying a high-viscosity treatment liquid to the slit nozzle 22 of the coating section 20 as a supply target.

The supply tank 31 is a tank for storing the processing liquid before supply. The supply unit 30 of the present embodiment has six supply grooves 31.

The liquid feed pipe 32 is a pipe for supplying the processing liquid from the supply tank 31 to the slit nozzle 22. One end (upstream end) of the liquid feeding pipe 32 is connected to a supply pipe 311 extending from each supply tank 31. The other end (downstream end) of the liquid feeding pipe 32 serves as a supply port 320 for supplying the processing liquid to the slit nozzle 22 to be supplied. That is, the other end of the liquid feeding pipe 32 is connected to the slit nozzle 22.

The main pump 33 is inserted into the liquid supply pipe 32. The main pump 33 feeds the processing liquid from the supply tank 31 toward the supply port 320. For the main pump 33, for example, a line pump such as a Coaxial line (CT) pump or a constant discharge line (PT) pump is used.

The degassing unit 34 is inserted in the liquid feeding pipe 32 on the upstream side of the main pump 33 and on the downstream side of the assist pump 35. Fig. 3 is a sectional view showing the structure of the degassing unit 34. The degassing unit 34 is a so-called hollow fiber membrane degassing module. As shown in fig. 3, the degassing unit 34 includes a cylindrical case 41, a plurality of hollow fiber membranes 42, and a pressure reducing mechanism 43.

The casing 41 has an inlet 411, an outlet 412, and two exhaust ports 413. The inlet 411 is provided at one end of the casing 41 and is connected to a portion of the liquid feeding pipe 32 upstream of the degassing unit 34. The outlet 412 is provided at the other end of the casing 41, and is connected to a portion of the liquid feeding pipe 32 downstream of the degassing unit 34. The exhaust port 413 is provided on a side portion of the casing 41 and connected to the decompression mechanism 43.

The hollow fiber membrane 42 is a thin cylindrical membrane. One ends of all the hollow fiber membranes 42 are connected to the inflow port 411 through flow paths. The other ends of all the hollow fiber membranes 42 are connected to the outlet 412. Thus, when the flow of the treatment liquid occurs in the liquid feeding pipe 32, the treatment liquid is supplied to the hollow fiber membranes 42 from the inlet 411 and is discharged from the outlet 412.

The hollow fiber membranes 42 are used for degassing treatment, and are formed of gas permeable membranes that do not allow liquid to pass therethrough and allow gas to pass therethrough. The hollow fiber membranes 42 used in the degassing unit 34 of the present embodiment have an inner diameter of 0.5mm to 3 mm. The number of hollow fiber membranes 42 used in the degassing unit 34 of the present embodiment is about 100 to 1000. The inner diameter and the number of the hollow fiber membranes 42 used in the degassing unit 34 are appropriately changed depending on the type and flow rate of the treatment liquid.

The decompression mechanism 43 includes a decompression pipe 431 and a decompression pump 432. One end of the pressure reducing pipe 431 is branched into two and connected to the exhaust port 413 of the housing 41. The other end of the decompression pipe 431 is connected to a decompression pump 432. When the decompression pump 432 is driven, gas is sucked from the space in the housing 41 through the decompression pipe 431 and the two exhaust ports 413. This reduces the air pressure in the space inside the housing 41. That is, the air pressure in the outer space of the hollow fiber membranes 42 decreases. In the example of fig. 3, two exhaust ports 413 are provided, but one exhaust port 413 may be provided, or three or more exhaust ports 413 may be provided.

As described above, by setting the external space of the hollow fiber membranes 42 to a pressure lower than the internal space of the hollow fiber membranes 42, it is possible to discharge bubbles in the liquid passing through the internal space of the hollow fiber membranes 42 or gas dissolved in the liquid to the external space of the hollow fiber membranes 42. This allows degassing of the liquid in the hollow fiber membranes 42.

The auxiliary pump 35 is inserted into the liquid feeding pipe 32 on the upstream side of the degassing unit 34 and on the downstream side of the filter 36. The auxiliary pump 35 pressurizes and supplies the processing liquid toward the degassing unit 34. The auxiliary pump 35 of the present embodiment is a type of a line pump called a Coaxial tube pump (CT) pump. Fig. 4 and 5 are sectional views showing the structure of the auxiliary pump 35. As shown in fig. 4 and 5, the auxiliary pump 35 includes a housing 50, a lower check valve (check valve)51, an upper check valve 52, a tube 53, and a fluid holding portion 54.

The frame 50 has an inlet 501 at its lower end and an outlet 502 at its upper end. The liquid feeding pipe 32 is connected to the inlet 501 at a portion upstream of the auxiliary pump 35. The liquid delivery pipe 32 is connected to the outlet 502 at a downstream side of the auxiliary pump 35. The lower check valve 51, the inner space of the pipe 53, and the upper check valve 52 are connected to flow paths in this order from the inlet 501 to the outlet 502, thereby constituting a flow path 500. Both the lower check valve 51 and the upper check valve 52 are check valves that allow only fluid flowing from below to above to pass therethrough.

The tube 53 is a shrinkable tubular member disposed inside the fluid holding portion 54. As described above, the tube 53 constitutes a part of the flow path 500.

The fluid holding portion 54 is a cylindrical member disposed outside the tube 53. The internal space of the fluid holding portion 54 constitutes a fluid reservoir 540. That is, the tube 53 is disposed inside the fluid storage chamber 540. The space outside the tube 53 of the fluid reservoir 540 is filled with an indirect fluid. The inner space of the tube 53 is not communicated with the outer space of the tube 53. Therefore, the treatment liquid flowing through the flow channel 500 does not mix with the indirect fluid filled in the fluid reservoir 540. The indirect fluid may be liquid or gas.

The fluid holding portion 54 includes a small-diameter bellows (bellows)541, a large-diameter bellows 542, a bellows center (bellows center)543, and a moving mechanism 544. The small-diameter corrugated tube 541 and the large-diameter corrugated tube 542 are each a bellows-shaped tubular member disposed in the vertical direction. The bellows center 543 is a ring-shaped member. The moving mechanism 544 is a mechanism for moving the position of the bellows center 543 in the vertical direction. The small-diameter corrugated tube 541 has a tube diameter smaller than that of the large-diameter corrugated tube 542. One end of the small-diameter corrugated tube 541 is fixed to the frame 50. The other end of the small-diameter bellows 541 and one end of the large-diameter bellows 542 are fixed to the bellows center 543. The other end of the large-diameter bellows 542 is fixed to the frame 50.

As shown in fig. 4, when the bellows center 543 is moved upward by the movement mechanism 544, the small-diameter bellows 541 becomes shorter in the vertical direction, and the large-diameter bellows 542 becomes longer in the vertical direction. This increases the volume of the fluid storage chamber 540, and decreases the pressure in the fluid storage chamber 540. As a result, the pressure in the pipe 53 also decreases, and the processing liquid is sucked into the pipe 53 from the upstream side of the liquid feeding pipe 32 through the inlet 501 and the lower check valve 51.

On the other hand, as shown in fig. 5, when the bellows center 543 is moved downward by the movement mechanism 544, the small-diameter bellows 541 becomes long in the vertical direction, and the large-diameter bellows 542 becomes short in the vertical direction. This reduces the volume of the fluid reservoir 540, and increases the pressure in the fluid reservoir 540. As a result, the pressure from the indirect fluid is applied to the outer peripheral surface of the pipe 53, and the processing liquid in the pipe 53 is discharged to the downstream side of the liquid supply pipe 32 through the upper check valve 52 and the outlet 502.

As described above, by moving the position of bellows center 543, the internal volume of fluid reservoir 540 may be increased or decreased. As a result, the treatment liquid can be sucked and discharged from the auxiliary pump 35.

As the auxiliary pump 35, as described above, it is preferable to use a so-called line pump of a type that sends liquid by applying the pressure of the fluid to the outer peripheral surface of the shrinkable tube. As described above, by pushing the pipe filled with the treatment liquid from the outside to discharge the treatment liquid, it is possible to suppress the occurrence of particles in the auxiliary pump 35 and the mixing of particles into the treatment liquid.

Fig. 6 is a sectional view showing another example of the structure of the auxiliary pump 35A. The exemplary auxiliary pump 35A of fig. 6 is one type of tubing pump known as a metered discharge Parallel Tubing (PT) pump.

In the auxiliary pump 35A of the example of fig. 6, the fluid reservoir 540A includes: a functional part 61A in which a tube 53A is disposed; a shaft arrangement portion 62A in which the drive shaft 55A is arranged; and a connecting portion 63A that connects the functional portion 61A and the shaft disposing portion 62A via a flow path. The drive shaft 55A can protrude into the shaft arrangement portion 62A. The side surface of the drive shaft 55A may have a bellows-like bellows.

As shown by the arrow in fig. 6, when the drive shaft 55A protrudes into the shaft arrangement portion 62A, the pressure of the indirect fluid in the shaft arrangement portion 62A increases. Thereby, the pressure of the indirect fluid also increases in the functional portion 61A, and the pressure from the indirect fluid is applied to the outer peripheral surface of the pipe 53A. As a result, the treatment liquid is discharged from the pipe 53A through the outflow port 502A.

Conversely, when the protruding drive shaft 55A returns to the original position, the pressure of the indirect fluid in the shaft arrangement portion 62A decreases. Thereby, the pressure of the indirect fluid also drops in the functional portion 61A, and the pressure in the pipe 53A also drops. As a result, the treatment liquid is sucked into the pipe 53A through the inflow port 501A.

Even if the auxiliary pump 35A of the example of fig. 6 is a line pump other than the CT pump, it is possible to suppress the particles from being generated in the auxiliary pump 35A and mixed into the treatment liquid.

The filter 36 is inserted into the liquid feeding pipe on the upstream side of the degassing unit 34 and the auxiliary pump 35. The filter 36 removes foreign matters contained in the treatment liquid flowing through the liquid feeding pipe 32.

The controller 10 is a member for controlling the operation of each part in the coating apparatus 1. As conceptually shown in fig. 1, the control Unit 10 includes a computer (computer) having an arithmetic Processing Unit 11 such as a Central Processing Unit (CPU), a Memory 12 such as a Random Access Memory (RAM), and a storage Unit 13 such as a hard disk drive (hard disk drive). The control unit 10 is electrically connected to each part in the coating unit 20 such as the lift pins and the traveling mechanism 24. The control unit 10 is also electrically connected to the valve provided in the supply unit 30, the main pump 33, the assist pump 35, the decompression pump 432, and the moving mechanism 544. The control unit 10 temporarily reads out a computer program (computer program) or data (data) stored in the storage unit 13 into the memory 12, and the operation of each unit in the coating apparatus 1 is controlled by performing an operation process by the operation processing unit 11 based on the computer program and the data. Thereby, the coating process of the substrate 9 is advanced.

The supply unit 30 of the coating apparatus 1 includes a degassing unit 34 and an auxiliary pump 35 as means for degassing the treatment liquid. In the degassing unit 34 having a plurality of hollow fiber membranes 42, the inner diameter of the hollow fiber membranes 42 is very small compared to the inner diameter of the liquid feeding pipe 32, and therefore the flow path resistance in the degassing unit 34 is larger than the flow path resistance in the liquid feeding pipe 32. Therefore, an auxiliary pump 35 for supplying the processing liquid to the degassing unit 34 is disposed immediately upstream of the degassing unit 34, independently of the main pump 33 for adjusting the discharge speed of the slit nozzle 22. This enables the treatment liquid to be smoothly supplied to each hollow fiber membrane 42 of the degassing unit 34.

As described above, in the degassing tank which is a conventional degassing mechanism, it takes time to degas. Therefore, when the consumption rate of the treatment liquid is high, the number of degassing tanks increases, and the entire apparatus becomes large. In contrast, in the supply section 30, deaeration can be performed by a small deaeration unit 34. In the degassing unit 34 using the hollow fiber membrane 42, the degassing treatment can be sufficiently performed even in the case where the treatment liquid passes at a relatively large flow rate. That is, the supply unit 30 can efficiently remove dissolved gas in a treatment liquid having a high viscosity, and can reduce the size of the apparatus.

In the present embodiment, as conceptually shown in fig. 1, the degassing unit 34 and the main pump 33 of the supply unit 30 are housed inside the housing 21 of the coating unit 20. Depending on the material forming the liquid delivery pipe 32, the liquid delivery pipe 32 may slightly transmit gas. As described above, the degassing unit 34 is disposed in the immediate vicinity of the slit nozzle 22, and thus the processing liquid subjected to the degassing process can be supplied to the slit nozzle 22 immediately before the gas is absorbed again.

< 2 > relating to respective processes in a coating apparatus

Next, each step in the coating apparatus 1 will be explained. Fig. 7 is a flowchart showing the flow of each step performed on the treatment liquid in the coating apparatus 1.

As shown in fig. 7, in the coating apparatus 1, when a flow from the supply tank 31 to the slit nozzle 22 is generated in the liquid feeding pipe 32 by the main pump 33 and the auxiliary pump 35, the processing liquid supplied from the supply tank 31 to the liquid feeding pipe 32 first removes foreign matters in the filter 36 (step S101).

Then, the processing liquid having passed through the filter 36 is supplied to the auxiliary pump 35. Next, the processing liquid is pressurized toward the degassing unit 34 by the auxiliary pump 35 and supplied to the downstream side of the liquid feeding pipe 32 (step S102). This allows the processing liquid to be smoothly supplied to the degassing unit 34 having a relatively large flow path resistance.

The treatment liquid supplied from the auxiliary pump 35 is supplied to the degassing unit 34 immediately after being discharged from the auxiliary pump 35. In the degassing unit 34, the treatment liquid passes through the inside of the plurality of hollow fiber membranes 42 whose outside space is depressurized. Thereby, the dissolved gas in the processing liquid is removed (step S103).

Next, the processing liquid from which the dissolved gas has been removed in the degassing unit 34 is sent by the main pump 33 and supplied to the slit nozzle 22 (step S104). The main pump 33 supplies the processing liquid necessary for the coating process in the slit nozzle 22 in an amount necessary for the coating process. The processing liquid supplied to the slit nozzle 22 is ejected and applied to the upper surface of the substrate 9 (step S105). As described above, the processing liquid in the supply tank 31 is degassed and then applied to the substrate 9.

< 3. modification example >

Although the embodiment of the present invention has been described above, the present invention is not limited to the embodiment.

In the above embodiment, the supply unit 30 as a supply device for supplying the high viscosity processing liquid is used together with the coating unit 20 having the slit nozzle 22 as a supply target, and the coating device 1 is configured as a whole. However, the present invention is not limited thereto. The supply device of the present invention may be a supply target other than a coating portion for coating the treatment liquid.

Further, the coating apparatus 1 is a process (process) for manufacturing the substrate itself of the flexible element, but the coating apparatus of the present invention may be applied to a process for forming a protective film on the surface of the substrate after the element is formed. The coating apparatus of the present invention can also be used for a process of coating an adhesive agent when bonding a substrate to a substrate. The coating apparatus of the present invention can be used in a process for manufacturing a liquid crystal display device or a semiconductor substrate other than a flexible element. The coating apparatus of the present invention can also be used in a process for manufacturing a battery such as a lithium ion (lithium ion) secondary battery or a fuel cell. That is, the coating apparatus of the present invention is particularly suitable for a process of coating a high-viscosity material.

Further, the details of the supply device and the coating device may be different from the structures shown in the respective drawings of the present application. Further, the respective elements appearing in the embodiment or the modification may be appropriately combined within a range not to contradict each other.

Claims

1. A supply device for supplying a processing liquid having a viscosity of thousands cP or more to a supply target, comprising:

a tank for storing the treatment solution;

a supply port that supplies the processing liquid to the supply target;

a liquid feeding pipe connecting the tank and the supply port via a flow path;

a main pump inserted in the liquid supply pipe and configured to supply the treatment liquid from the tank to the supply port;

a degassing unit interposed in the liquid supply pipe on an upstream side of the main pump;

an auxiliary pump interposed in the liquid supply pipe on an upstream side of the degassing unit, for pressurizing the processing liquid toward the degassing unit; and

a filter interposed between the degassing unit and the auxiliary pump on the upstream side of the liquid feeding pipe,

the degassing unit comprises:

a cylindrical housing;

a plurality of hollow fiber membranes housed inside the housing; and

and a decompression mechanism configured to decompress the space inside the housing and outside the hollow fiber membrane.

2. The supply device according to claim 1,

the auxiliary pump includes:

a fluid reservoir capable of increasing or decreasing the internal volume; and

a collapsible tube constituting a flow path and disposed inside the fluid storage chamber,

when the volume of the fluid reservoir chamber is reduced, the pressure applied to the outer circumferential surface of the pipe is increased, and the volume in the pipe is reduced, thereby discharging the processing liquid from the pipe.

3. The supply device according to claim 2,

the auxiliary pump is a coaxial pipeline pump.

4. The supply device according to any one of claims 1 to 3,

the treatment liquid is a varnish containing a polyimide precursor,

the supply target is a nozzle that ejects the varnish.

5. A coating apparatus that coats a surface to be treated with a liquid, the coating apparatus comprising:

the supply device of any one of claims 1 to 4; and

and a nozzle which is the supply target of the supply device and has an ejection port for ejecting the treatment liquid.

6. The coating apparatus of claim 5, further comprising:

a frame body having a stage on an upper surface thereof, the stage being configured to carry a substrate to be processed,

the nozzle is movably disposed on an upper portion of the stage,

the main pump and the degassing unit are housed in the housing.

7. A supply method for supplying a processing liquid having a viscosity of thousands cP or more to a supply target, the supply method comprising:

a) pressurizing and supplying the treatment liquid toward a degassing unit by an auxiliary pump after the treatment liquid supplied from a tank storing the treatment liquid is filtered through a filter;

b) in the degassing unit, the treatment liquid passes through the plurality of hollow fiber membranes whose outside spaces are depressurized, thereby removing dissolved gas in the treatment liquid; and

c) the treatment liquid passed through the degassing unit is delivered by a main pump.