JP2013137139A - Drying device and heat treatment system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drying device in which an increase in a concentration of an organic solvent in hot air to be supplied to a chamber is suppressed, and which is excellent in the efficiency of energy consumption, and to provide a heat treatment system including the drying device.SOLUTION: A drying part 40 for housing a base material coated with a coating agent including an organic solvent includes a lower hot air spouting part 51 and a lower exhaust box 55. A hot air supply part 53 supplies hot air into the chamber of the drying part 40 from the lower hot air spouting part 51. The hot air spouted to the base material from the lower hot air spouting part 51 is recovered by the lower exhaust box 55, and discharged as exhaust gas including the organic solvent through an exhaust tube 92 to an exhaust part 93. At this time, heat is exchanged between high-temperature exhaust gas and gas taken in from both ends of an outer tube 85, and the temperature of the gas flowing through a space 99 is increased. The temperature-increased gas is supplied from a circulation tube 86 to the hot air supply part 53 and heated, and spouted into the chamber of the drying part 40 from the lower hot air spouting part 51.

Description

  The present invention relates to a drying apparatus that performs a drying process on a substrate coated with a coating agent containing an organic solvent, and a heat treatment system incorporating the drying apparatus.

  In the manufacturing process of an electrode of a chemical battery such as a lithium ion battery or a magnetic recording medium, a substrate coated with a coating agent containing an organic solvent is dried. Drying of the coating agent containing the organic solvent proceeds as the organic solvent evaporates. Although the evaporated organic solvent is discharged as exhaust gas, the organic solvent is generally flammable, and it is necessary to keep the concentration of the organic solvent in the exhaust gas below the minimum explosion limit concentration.

  For this reason, in Patent Document 1, a plurality of drying chambers are arranged in series along the traveling direction of a belt-like support (web) coated with a coating agent containing an organic solvent. It is disclosed that exhaust gas is joined to a joining duct and then exhausted by an exhaust blower. Since the exhaust gas from the high solvent concentration drying chamber is diluted with the exhaust gas from the low solvent concentration drying chamber, the concentration of the organic solvent in the exhaust blower can be kept below the minimum explosion limit concentration.

  Further, in Patent Document 1, a plurality of exhaust ducts having suction ports are provided at different positions in each drying chamber, and an exhaust duct having suction ports is provided in an area where the solvent concentration is low, and exhaust gas is supplied to a circulation blower of an air supply system. It is disclosed to be used as a duct for circulation. As a result, only the exhaust gas having a low concentration of the organic solvent is circulated to the supply system, so that the concentration of the organic solvent in the circulation blower can be kept below the minimum explosion limit concentration.

JP 2003-202188 A

  However, in the drying apparatus disclosed in Patent Document 1, exhaust gas containing an organic solvent is circulated to the air supply system even though the concentration is low, so that if any trouble occurs during operation, the drying apparatus is dried. There is a risk that the concentration of the organic solvent in the gas supplied to the chamber will rapidly increase and cause an explosion.

  In addition, since fresh air is mixed with the exhaust gas circulated from the drying chamber in order to keep the concentration of the organic solvent in the air supply system low, fresh air is supplied when hot air is supplied in the drying chamber. It is necessary to perform additional heating in order to prevent temperature drop due to air. As a result, the problem of increased energy consumption has also occurred.

  The present invention has been made in view of the above problems, and a drying apparatus excellent in energy consumption efficiency while suppressing an increase in the concentration of an organic solvent in hot air supplied to a chamber, and a heat treatment incorporating the drying apparatus The purpose is to provide a system.

  In order to solve the above-mentioned problems, a first aspect of the present invention provides a drying apparatus for drying a base material coated with a coating agent containing an organic solvent, a chamber for storing the base material, and hot air in the chamber. Hot air supply means for supplying air, an exhaust pipe that is connected to the chamber and exhausts the atmosphere in the chamber, and an outside air intake port, and covers the exhaust pipe so as to separate the space from the outer wall of the exhaust pipe An outer pipe, a circulation pipe that communicates and connects the hot air supply means with a space formed between an outer wall of the exhaust pipe and an inner wall of the outer pipe, and is provided in the middle of the path of the circulation pipe. Blowing means for blowing gas toward the hot air supply means, and organic solvent detection means for detecting the concentration of organic solvent in the gas flowing in the circulation pipe provided in the path of the circulation pipe. And

  According to a second aspect of the present invention, in the drying apparatus according to the first aspect of the present invention, outside air intake ports are formed at both ends of the outer tube.

  The invention of claim 3 is the drying apparatus according to claim 2, wherein the intake port formed at each of both ends of the outer tube is smaller in diameter than the central portion of the outer tube. Features.

  The invention according to claim 4 is the drying apparatus according to any one of claims 1 to 3, wherein the turbulent flow forming member is configured to turbulently flow the air flowing through the space inside the outer tube. Is arranged in the space.

  Further, the invention of claim 5 provides a warning when the organic solvent concentration detected by the organic solvent detection means exceeds the first set value in the drying apparatus according to any one of claims 1 to 4. And a control means for stopping the drying device when a second set value larger than the first set value is exceeded.

  The invention of claim 6 is the drying apparatus according to any one of claims 1 to 5, wherein the outer tube includes a metal tube and a heat insulating material coated on an outer wall of the metal tube. Features.

  According to a seventh aspect of the present invention, in the drying apparatus according to any one of the first to sixth aspects, a heat insulating material is provided on the outer wall of the circulation pipe.

  The invention of claim 8 is characterized in that in the drying apparatus according to any one of claims 1 to 7, a filter is provided in the course of the circulation pipe.

  According to a ninth aspect of the present invention, in the drying apparatus according to any one of the first to eighth aspects, the exhaust pipe is formed of an aluminum alloy or stainless steel.

  Further, the invention of claim 10 is a heat treatment system, wherein a coating processing unit that coats a coating agent on a substrate to form a coating film, and a preheating unit that preheats the coating film And a drying device according to any one of claims 1 to 9, and a cooling unit that cools the substrate after the drying process.

  According to the first to tenth aspects of the present invention, the outer pipe that covers the exhaust pipe is provided so as to separate the space from the outer wall of the exhaust pipe that exhausts the atmosphere in the chamber, and the space and the hot air supply means are connected in communication. Since the circulation pipe is provided, heat exchange is performed between the exhaust gas flowing through the exhaust pipe and the gas taken into the outer pipe, and the heated gas is supplied to the hot air supply unit. Energy consumption can be suppressed and excellent energy consumption efficiency can be obtained. Also, the exhaust gas and the gas newly taken into the outer pipe are completely separated from each other by the exhaust pipe, and the organic solvent is prevented from being mixed into the gas, and the organic solvent in the hot air supplied to the chamber The increase in the concentration of can be suppressed.

  In particular, according to the invention of claim 2, since the outside air intake ports are formed at both ends of the outer pipe, the contact area between the taken-in low temperature outside air and the exhaust pipe is increased, and the efficiency of heat exchange is improved. To do.

  In particular, according to the invention of claim 3, since the diameter of the intake port formed at each of both ends of the outer tube is smaller than the inner diameter of the central portion of the outer tube, the gas taken in near both ends of the outer tube It becomes a turbulent flow, and the heat exchange efficiency with the outer wall surface of the exhaust pipe can be further increased.

  In particular, according to the fourth aspect of the present invention, the turbulent flow forming member that turbulently flows the air flowing in the space inside the outer pipe is disposed in the space, so that the gas flowing in the space becomes turbulent. Thus, the efficiency of heat exchange with the outer wall surface of the exhaust pipe can be further increased.

  In particular, according to the invention of claim 5, when the concentration of the organic solvent detected by the organic solvent detecting means exceeds the first set value, a warning is issued and the second larger than the first set value is issued. Since the control means for stopping the drying device when the set value is exceeded is further provided, it is possible to reliably prevent an explosion or fire caused by leakage of the organic solvent from the exhaust pipe.

  In particular, according to the invention of claim 6, since the outer tube includes the metal tube and the heat insulating material coated on the outer wall of the metal tube, the temperature reduction of the gas in the outer tube is prevented and the energy consumption efficiency is excellent. Can be.

  In particular, according to the invention of claim 7, since the heat insulating material is provided on the outer wall of the circulation pipe, it is possible to prevent the temperature of the gas from being lowered in the circulation pipe and to improve the energy consumption efficiency.

  In particular, according to the invention of claim 8, since the filter is provided in the course of the circulation pipe, the gas flowing through the circulation pipe can be cleaned, and contamination of the substrate can be reduced.

  In particular, according to the invention of claim 9, since the exhaust pipe is formed of aluminum alloy or stainless steel, high heat exchange efficiency can be maintained.

It is a figure which shows the whole heat processing system structure incorporating the drying apparatus which concerns on this invention. It is a figure which shows schematic structure of a preheating part and a drying part. It is a figure which shows the structure of a preheating part. It is a figure which shows the structure of a drying part. It is a figure which shows the structure of an annealing part. It is a figure which shows the structure of a cooling unit. It is a figure which shows schematic structure of a waste heat recovery system. It is sectional drawing which cut | disconnected the exhaust pipe and the outer pipe | tube in the longitudinal direction. It is the figure which looked at the exhaust pipe and the outer pipe from the AA cross section of FIG. It is sectional drawing which cut | disconnected the circulation pipe in the longitudinal direction.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing an overall configuration of a heat treatment system 1 incorporating a drying apparatus according to the present invention. In addition, in FIG. 1 and subsequent figures, in order to clarify the directional relationship, an XYZ orthogonal coordinate system in which the Z-axis direction is a vertical direction and the XY plane is a horizontal plane is appropriately attached. Further, in FIG. 1 and the subsequent drawings, the dimensions and numbers of the respective parts are exaggerated or simplified as necessary for easy understanding.

  In this heat treatment system 1, an active material coating agent as an electrode material is applied onto a metal foil as a base material to form a coating film, and the coating film is dried to obtain a lithium ion secondary material. This is an apparatus for manufacturing an electrode for a secondary battery. The heat treatment system 1 includes a coating processing unit 10, a preheating unit 20, a drying unit 40, an annealing unit 60, a cooling unit 70, and a transport mechanism 80. The heat treatment system 1 also includes a pump unit 15 that feeds a coating solution of electrode material to the coating processing unit 10, and an electrical box 9 that houses a control unit 90, a power source, and the like.

  The base material 5 is a metal foil that functions as a current collector of a lithium ion secondary battery. When the positive electrode of the lithium ion secondary battery is manufactured by the heat treatment system 1, for example, an aluminum foil (Al) can be used as the base material 5. Moreover, when manufacturing a negative electrode with the heat processing system 1, copper foil (Cu) can be used as the base material 5, for example. The base material 5 is a long sheet-like (strip-shaped) metal foil, and the width and thickness thereof are not particularly limited. For example, the width may be 600 mm to 700 mm and the thickness may be 10 μm to 20 μm. .

  The long base material 5 is fed from the unwinding roller 81 and wound by the winding roller 82, so that the coating processing unit 10, the preheating unit 20, the drying unit 40, the annealing unit 60, and the cooling unit 70 are sequentially arranged. Be transported. The transport mechanism 80 includes the unwinding roller 81, the winding roller 82, and a plurality of auxiliary rollers 83a to 83e. In addition, about the number and arrangement | positioning of auxiliary roller 83a-83e, it is not limited to the example of FIG. 1, It can increase / decrease suitably as needed.

The coating processing unit 10 includes a coating nozzle 11 and a backup roller 12. An active material coating agent, which is an electrode material, is applied from the coating nozzle 11 to the surface of the substrate 5 that is traveling while being supported by the backup roller 12. When the positive electrode is manufactured by the heat treatment system 1, as a positive electrode material from the coating nozzle 11, for example, lithium cobaltate (LiCoO ₂ ) as a positive electrode active material, carbon (C) as a conductive auxiliary agent, and a binder. A mixed liquid of a certain polyvinylidene fluoride (PVDF) and an organic solvent N-methyl-2-pyrrolidone (NMP) is applied to the substrate 5. Instead of lithium cobaltate, lithium nickelate (LiNiO ₂ ), lithium manganate (LiMn ₂ O ₄ ), lithium iron phosphate (LiFePO ₄ ), or the like can be used as the positive electrode active material, but it is not limited thereto. It is not something.

On the other hand, when the negative electrode is produced by the heat treatment system 1, as a negative electrode material from the coating nozzle 11, for example, a mixed liquid of graphite (graphite) as a negative electrode active material, PVDF as a binder, and NMP as an organic solvent. Is applied to the substrate 5. Instead of graphite, hard carbon, lithium titanate (Li ₄ Ti ₅ O ₁₂ ), silicon alloy, tin alloy, or the like can be used as the negative electrode active material. In both the positive electrode material and the negative electrode material, styrene-butadiene rubber (SBR) or the like can be used as a binder instead of PVDF. These coating materials for the positive electrode material and the negative electrode material are slurries in which solids (fine particles) are dispersed, the viscosity of which is 1 Pa · s (pascal second) or more, and generally has thixotropic properties. Further, both the positive electrode material and the negative electrode material coating agent applied to the substrate 5 contain NMP as an organic solvent.

  As the coating nozzle 11, a slit nozzle provided with slit-like discharge ports along the width direction of the substrate 5 can be used. The coating nozzle 11 applies the coating material of the electrode material fed from the pump unit 15 to the traveling base material 5 by discharging it from the discharge port, and applies a coating film of the electrode material on the surface of the base material 5. Form. The thickness of the coating film of the electrode material formed on the surface of the substrate 5 in the coating treatment unit 10 is several hundred microns, which is 10 times or more the thickness of the substrate 5. Even when such a relatively thick coating film is formed, since the electrode material is a high-viscosity slurry having a viscosity of 1 Pa · s (Pascal second) or more, liquid dripping or the like does not occur immediately. The base material 5 on which the coating film of the electrode material is formed in the coating processing unit 10 is transported in order by the transport mechanism 80 to the preheating unit 20, the drying unit 40, the annealing unit 60, and the cooling unit 70 to dry the coating film. Processing is performed.

  The heat treatment system 1 of the present embodiment is provided with three zones for heating the electrode material coating film formed on the substrate 5. The preheating part 20 which is a 1st heating zone in order from the upstream raises the temperature of the coating film formed on the base material 5, and preheats for a fixed time. Moreover, the drying part 40 which is a 2nd heating zone is a process part which performs the main drying process (constant rate drying), and heats the coating film preheated in the preheating part 20, and evaporates an organic solvent. Furthermore, the annealing unit 60 heats the coating film to a higher temperature, removes the organic solvent still remaining on the coating film (decrease drying), and performs the coating film by a drying process in the drying unit 40. Eliminates strain and residual stress generated inside.

  FIG. 2 is a diagram showing a schematic configuration of the preheating unit 20 and the drying unit 40. FIG. 3 is a diagram showing the configuration of the preheating unit 20. The preheating unit 20 includes a ventilation box 25 and a hot air ejection unit 31 inside a chamber 21 having openings at both ends. The preheating unit 20 includes a hot air supply unit 27 that supplies hot air to the ventilation box 25 and a hot air supply unit 33 that supplies hot air to the hot air ejection unit 31.

  The chamber 21 is provided so as to surround the transport path PL along which the base material 5 is transported by the transport mechanism 80. Openings for allowing the base material 5 to pass through are formed at both ends of the chamber 21. Inside the chamber 21, a plurality of hot-air ejection portions 31 (six in this embodiment) are provided along the transport direction (X direction) of the base material 5 below the transport path PL. Further, inside the chamber 21, a plurality of ventilation boxes 25 (three in the present embodiment) are provided along the conveyance direction of the base material 5 above the conveyance path PL. Although the length (furnace length) of the chamber 21 of the preheating part 20 is not specifically limited, In this embodiment, it is about 1000 mm.

  Each hot-air ejection part 31 is provided with a plurality of ejection holes (not shown) facing upward. The hot air ejection part 31 is connected to the hot air supply part 33 through a pipe 32. The hot air supply unit 33 includes a heater and a blower, and supplies heated air to the hot air jet unit 31 as hot air. The plurality of hot air ejection units 31 eject the hot air supplied from the hot air supply unit 33 from the ejection holes toward the upper conveyance path PL.

  Each ventilation box 25 is a hollow box, and the hollow portion is a ventilation portion 23 through which gas can pass. The ventilation box 25 is formed of a metal material (for example, stainless steel) having excellent heat resistance. In this embodiment, the three ventilation boxes 25 are connected in series along the conveyance direction of the base material 5. That is, the most upstream (leftmost in FIGS. 2 and 3) ventilation box 25 and the central ventilation box 25 are connected by the connecting pipe 28 along the conveyance direction of the base material 5. The most downstream ventilation box 25 is connected by a connecting pipe 28. For this reason, the ventilation portions 23 of the three ventilation boxes 25 are connected to each other via the connecting pipe 28.

  Further, the most upstream ventilation box 25 is connected to the hot air supply unit 27 through a blower pipe 29. A flow rate adjusting valve 26 is inserted in the middle of the route of the blower pipe 29. The hot air supply unit 27 includes a heater and a blower, and sends the air heated by the heater to the blow pipe 29 as hot air by the blower. The hot air sent out to the ventilation pipe 29 flows into the ventilation part 23 of the most upstream ventilation box 25, then passes through the first connecting pipe 28 and flows into the ventilation part 23 of the central ventilation box 25, and further 2 It passes through the second connecting pipe 28 and flows into the ventilation portion 23 of the most downstream ventilation box 25 (see FIG. 3). The hot air supply unit 27 causes the hot air to flow through the ventilation portions 23 of the ventilation boxes 25 so that the ventilation boxes 25 are heated. The flow rate of hot air flowing through each ventilation box 25 is defined by a flow rate adjustment valve 26. The hot air flowing into the ventilation portion 23 of the most downstream ventilation box 25 is sent to the air guide pipe 35 and supplied to the upper hot air ejection portion 45 of the drying unit 40.

  Ceramic plates 24 that emit infrared rays when heated are provided on the lower surfaces of the three ventilation boxes 25. The ceramic plate 24 may be formed by performing ceramic spraying on the entire lower surface of the ventilation box 25. As a ceramic material constituting the ceramic plate 24, an alumina, titania, zirconia, or the like that emits infrared rays when heated, or a mixture thereof can be used. The ceramic plate 24 made of such a ceramic material emits far-infrared rays having a relatively long wavelength when heated and heated. In addition, since the gas injection hole etc. are not provided in the lower surface of the ventilation box 25 and the ceramic plate 24, the hot air which flowed into the ventilation part 23 is not injected from the lower surface of the ventilation box 25. FIG.

  The base material 5 on which the coating film of the electrode material is formed in the coating processing unit 10 is transported to the preheating unit 20 along the transport path PL by the transport mechanism 80. When the base material 5 passes through the preheating part 20 from the (−X) side to the (+ X) side in FIGS. 2 and 3, the coating film formed on the base material 5 is from the hot air ejection part 31. Are heated by hot air jets and infrared radiation from the ceramic plate 24. That is, when the hot air blowing unit 31 to which hot air is supplied from the hot air supply unit 33 blows hot air from below the base material 5, the base material 5 is directly heated, and heat conduction from the base material 5 The coating film of electrode material is heated. In addition, the hot air supplied from the hot air supply unit 27 flows into the ventilation portions 23 of the three ventilation boxes 25, so that the ceramic plates 24 provided on the lower surfaces of the ventilation boxes 25 are heated. Infrared rays are emitted toward the coating film formed on the substrate 5. The coating film of the electrode material is also heated by receiving infrared radiation from the ceramic plate 24 (that is, by thermal radiation).

  By being heated from above and below by such hot air jetting from the hot air jetting part 31 and infrared radiation from the ceramic plate 24, the coating film of the electrode material formed on the substrate 5 is preheated. In the present embodiment, hot air is not blown directly from above the substrate 5 on which the slurry-like coating film is formed immediately after coating, but is heated by infrared radiation. For this reason, the coating film is not dried rapidly, and the problem that only the surface layer of the coating film is dried and the inside is not sufficiently dried can be prevented. Moreover, the crack of the coating film resulting from rapid drying can also be prevented. Furthermore, since the infrared ray radiated from the heated ceramic plate 24 is an infrared ray having a relatively long wavelength, even a thick coating film can be uniformly heated not only from the surface layer but also from the inside. As a result, it can prevent more reliably that only the surface layer of a coating film is dried.

  Although the temperature of the hot air blown from the lower side of the base material 5 by the hot air blowing portion 31 depends on the material of the coating film, it is about 50 ° C. to 300 ° C. On the other hand, the temperature of the hot air supplied from the hot air supply unit 27 to the ventilation portion 23 of the most upstream ventilation box 25 is at least higher than the temperature of the hot air blown from the hot air ejection unit 31 to the base material 5. This is because the hot air discharged from the ventilation box 25 is reused in the drying unit 40. Moreover, the heating efficiency of the coating film by infrared radiation increases when high-temperature hot air is supplied from the ventilation box 25.

  Moreover, while the hot air blowing part 31 blows hot air upward from below the base material 5, the coating film is indirectly heated, and a force that rises upward on the base material 5 acts by the wind pressure of the hot air. As a result, the base material 5 is not bent between the auxiliary roller 83a and the auxiliary roller 83b without providing a roller specific to the preheating unit 20, and (+ X) from the (−X) side along the transport path PL. ) Is transported toward the side. That is, the hot air ejection part 31 mainly plays the role of heating the coating film formed on the base material 5 by blowing hot air, but the transport mechanism 80 is configured to float and transport the base material 5. Will also play an auxiliary role.

  In addition, the number of ventilation boxes 25 and hot-air ejection portions 31 provided in the preheating unit 20 is not limited to the example of the above-described embodiment, and may be appropriate according to the length of the preheating unit 20 and the like. . The order of ventilation in the three ventilation boxes 25 of the preheating unit 20 is not limited to the above example (from the upstream side to the downstream side in the conveyance direction of the base material 5), and can be changed as appropriate. . For example, conversely to the above example, hot air is vented in order from the downstream ventilation box 25 in the conveyance direction of the base material 5 toward the upstream ventilation box 25 (from the right side to the left side in FIGS. 2 and 3). May be. Furthermore, instead of sequentially passing hot air in series through the three ventilation boxes 25, hot air may be individually supplied in parallel. Specifically, the three airflow ducts 25 are connected to each of the three ventilation boxes 25, and the hot air individually supplied to the three ventilation boxes 25 passes through the airflow ducts 35 and is dried by the drying unit 40. Is supplied to the upper hot air blowing portion 45.

  Next, FIG. 4 is a diagram illustrating a configuration of the drying unit 40. The drying unit 40 includes an upper hot air ejection unit 45, a lower hot air ejection unit 51, an upper exhaust box 56, and a lower exhaust box 55 inside a chamber 41 having openings at both ends. Further, the drying unit 40 includes a hot air supply unit 53 (FIG. 2) that supplies hot air to the lower hot air ejection unit 51, an exhaust unit 58 (FIG. 4) that applies a negative pressure to the upper exhaust box 56, and a lower exhaust box 55. An exhaust part 93 (FIG. 4) is provided for applying a negative pressure to the air.

  The chamber 41 is provided so as to surround a transport path PL along which the base material 5 is transported by the transport mechanism 80. At both ends of the chamber 41, a carry-in port 41a into which the base material 5 is carried in and a carry-out port 41b through which it is carried out are formed. Inside the chamber 41, on the upper side of the transport path PL, a plurality of upper hot air ejection portions 45 (five in the present embodiment) and a plurality of upper exhaust boxes 56 (six in the present embodiment) are transport path PL ( (Along the X direction). On the other hand, on the inner side of the chamber 41, a plurality of lower hot-air ejection portions 51 (five in this embodiment) and a plurality of lower exhaust boxes 55 (six in this embodiment) are provided below the transport path PL. Similarly, they are alternately arranged along the transport path PL. The length of the chamber 41 of the drying unit 40 is not particularly limited, but is about 3000 mm in this embodiment. In addition, the sizes of the carry-in port 41a and the carry-out port 41b are not particularly limited, but in the present embodiment, an interval of about 5 mm can be secured above and below the conveyance path PL (that is, the size in the vertical direction). Is about 10 mm).

  Each of the five lower hot air ejection portions 51 provided on the lower side of the transport path PL includes a plurality of ejection holes (not shown) facing upward, similar to the hot air ejection portion 31 of the preheating portion 20. Yes. The lower hot air ejection part 51 is connected in communication with a hot air supply part 53 via a pipe 52 (FIG. 2). That is, while the base end side of the piping 52 is connected to the hot air supply part 53, the front end side is branched into five, and each is connected to the lower hot air ejection part 51. A flow rate adjustment valve 54 is inserted in each of the five branched pipes 52 (FIG. 4). The hot air supply unit 53 includes a heater and a blower, and supplies the heated air as hot air to the lower hot air ejection unit 51. The flow rate of the hot air supplied to each of the five lower hot air ejection portions 51 is individually adjusted by the corresponding flow rate adjustment valve 54. The five lower hot air ejection parts 51 eject the hot air supplied from the hot air supply part 53 from the ejection holes toward the upper conveyance path PL.

  In the drying unit 40, an upper hot air blowing unit 45 that blows hot air directly onto the coating film on the substrate 5 is provided on the upper side of the transport path PL. Each of the five upper hot air ejection portions 45 includes a rectifying plate 43 and an ejection head 46. The current plate 43 is a plate-like member provided so as to be parallel to the transport path PL. The current plate 43 may be substantially parallel to the transport path PL. The rectifying plate 43 is provided with slit-like ejection holes extending along the width direction of the substrate 5.

  The ejection head 46 is connected to the air guide tube 35 and ejects hot air supplied from the air guide tube 35 from the ejection holes of the rectifying plate 43 toward the base material 5 in the transport path PL. As shown in FIG. 2, the proximal end side of the air guide pipe 35 is connected to the most downstream ventilation box 25 along the conveyance direction of the base material 5, and the distal end side is branched into five parts. It is connected in communication with the ejection head 46 of the upper hot air ejection part 45. A flow rate adjusting valve 36 is inserted in each of the five air guide pipes 35 (FIG. 4). As a result, the hot air sent from the hot air supply unit 27 to the ventilation pipe 29 passes through the ventilation portions 23 of the three ventilation boxes 25 and is then guided to the five upper hot air ejection portions 45 by the air guide pipe 35. . At this time, the flow rate of the hot air guided to each of the five upper hot air ejection portions 45 is individually adjusted by the corresponding flow rate adjustment valve 36. The hot air guided to the upper hot air jet part 45 by the air guide pipe 35 passes through the internal space of the jet head 46 and is jetted from the jet hole of the rectifying plate 43 toward the coating film on the substrate 5. .

  In addition, as shown in FIG. 4, the five upper hot air ejection portions 45 and the five lower hot air ejection portions 51 are arranged to face each other across the transport path PL. That is, the lower hot-air ejection portions 51 are provided in one-to-one correspondence with the five upper hot-air ejection portions 45, and the lower hot-air ejection portions 51 are directly below the ejection head 46 of each upper hot-air ejection portion 45. Be placed. Accordingly, hot air is blown from the lower hot air blowing portion 51 and the upper hot air blowing portion 45 to the same position on the upper and lower surfaces of the base material 5.

  A ceramic plate 42 that emits infrared rays when heated is provided on the lower surface of the rectifying plate 43 of each upper hot-air ejection part 45. The ceramic plate 42 is the same as the ceramic plate 24 provided on the lower surface of the ventilation box 25. That is, as the ceramic material constituting the ceramic plate 42, an alumina-based, titania-based, zirconia-based, or the like that emits infrared rays when heated, or a mixture thereof can be used. The ceramic plate 42 is formed by performing ceramic spraying on the lower surface of the rectifying plate 43 using these materials.

  In addition, six upper exhaust boxes 56 are provided for the five upper hot air ejection parts 45, and the upper hot air ejection part 45 is provided between the upper exhaust boxes 56 arranged adjacent to each other. Each upper exhaust box 56 includes a suction port extending along the width direction of the substrate 5 at the lower end. Each upper exhaust box 56 is connected to an exhaust part 58 through an exhaust pipe 57. In other words, the proximal end side of the exhaust pipe 57 is connected to the exhaust part 58, and the distal end side is branched into six, and each is connected to the upper exhaust box 56. A flow rate adjusting valve 91 is inserted in each of the six branched exhaust pipes 57. The exhaust unit 58 includes a suction blower and applies a negative pressure to the upper exhaust box 56 via the exhaust pipe 57. As a result, the upper exhaust box 56 sucks the atmosphere around the suction port at the lower end and discharges it to the exhaust pipe 57. The exhaust flow rate of the gas sucked by each of the six upper exhaust boxes 56 is individually adjusted by the corresponding flow rate adjusting valve 91.

  Similarly, six lower exhaust boxes 55 are provided for the five lower hot air ejection portions 51 below the transport path PL, and the lower exhaust boxes 55 disposed adjacent to each other are disposed below. A side hot air ejection part 51 is provided. Each lower exhaust box 55 includes a suction port extending along the width direction of the base material 5 at the upper end. The lower exhaust box 55 is connected to the exhaust part 93 through an exhaust pipe 92. That is, the proximal end side of the exhaust pipe 92 is connected to the exhaust part 93, and the distal end side is branched into six parts, and each is connected to the lower exhaust box 55. A flow rate adjusting valve 94 is inserted in each of the six branched exhaust pipes 92. The exhaust unit 93 includes a suction blower, and applies a negative pressure to the lower exhaust box 55 via the exhaust pipe 92. As a result, the lower exhaust box 55 sucks the atmosphere around the suction port at the upper end and discharges it to the exhaust pipe 92. The exhaust flow rate of the gas sucked by each of the six lower exhaust boxes 55 is individually adjusted by the corresponding flow rate adjusting valve 94. Further, in the present embodiment, the periphery of the exhaust pipe 92 is covered by the outer pipe 85, which will be described later.

  As shown in FIG. 4, six upper exhaust boxes 56 and six lower exhaust boxes 55 are arranged to face each other across the transport path PL. That is, the lower exhaust box 55 is provided in a one-to-one correspondence with the six upper exhaust boxes 56, and the lower exhaust box 55 is disposed directly below each of the six upper exhaust boxes 56. . Thereby, gas suction by the upper exhaust box 56 and the lower exhaust box 55 is performed from the same position on the upper and lower surfaces of the base material 5.

  The substrate 5 on which the electrode material coating film has been preheated by the preheating unit 20 is conveyed by the conveyance mechanism 80 from the carry-in port 41a of the drying unit 40 toward the carry-out port 41b along the conveyance path PL. When the base material 5 passes through the drying unit 40 from the (−X) side to the (+ X) side in FIGS. 2 and 4, the coating film warmed by the preheating unit 20 is the upper hot air ejection unit 45 and the lower side. It is heated by hot air jetting from the side hot air jetting part 51. That is, the lower hot air blowing part 51 to which hot air is supplied from the hot air supply part 53 blows hot air from below the base material 5, thereby directly heating the base material 5, and heat from the base material 5. The coating film of the electrode material is heated by conduction. The hot air blown to the lower surface of the base material 5 from the lower hot air ejection part 51 is collected by the lower exhaust box 55 provided on both sides of the lower hot air ejection part 51. Also, the hot air guided from the ventilation box 25 of the preheating unit 20 through the air guide pipe 35 is blown from above the base material 5 from the upper hot air blowing unit 45, whereby the coating film is directly heated by the hot air.

  As shown in FIG. 4, the hot air blown from the ejection head 46 of the upper hot air ejection section 45 to the upper surface of the base material 5 is based on the space between the rectifying plate 43 and the base material 5 provided in parallel with the transport path PL. It flows along the conveyance direction (X direction) of the material 5 and is collected in the upper exhaust box 56 provided on both sides of the upper hot air ejection part 45. Since hot air flows between the rectifying plate 43 and the base material 5, the coating film formed on the base material 5 is kept in contact with hot air with low humidity, and the coating film is efficiently dried by heating. Can do. Moreover, the temperature fall of a hot air can be suppressed to the minimum. Furthermore, when hot air flows between the rectifying plate 43 and the base material 5, the ceramic plate 42 provided on the lower surface of the rectifying plate 43 is also heated. As a result, infrared rays are emitted from the heated ceramic plate 42 toward the coating film formed on the substrate 5, and the coating film is also heated.

  The coating film of the electrode material formed on the base material 5 is heated from above and below by the hot air jets from the upper hot air jet part 45 and the lower hot air jet part 51 and the infrared radiation from the ceramic plate 42. As a result, the organic solvent (NMP in this embodiment) evaporates from the coating film and the drying process proceeds. In the drying unit 40, hot air is blown directly onto the coating film, but since hot air is already blown on the preheated coating film in the preheating unit 20, cracks caused by rapid drying of the coating film There is no risk of malfunction. Rather, by directly spraying hot air on the coating film preheated by the preheating unit 20 by the drying unit 40, evaporation of the organic solvent can be promoted and the coating film can be efficiently dried.

  In addition, the five lower hot air jetting parts 51 blow hot air from below the base material 5 upward, thereby indirectly heating the coating film, and the force that rises upward on the base material 5 by the wind pressure of the hot air Works. As a result, as in the preheating unit 20, the base member 5 does not bend between the auxiliary roller 83b and the auxiliary roller 83c without providing a roller specific to the drying unit 40, and along the conveyance path PL. Then, it is transported from the (−X) side to the (+ X) side. That is, the lower hot-air ejection part 51 also plays an auxiliary role of the transport mechanism 80 that floats and transports the base material 5.

  Further, since the five upper hot air ejection portions 45 and the five lower hot air ejection portions 51 are arranged to face each other across the transport path PL, the lower hot air ejection portion 51 and the lower surface of the base material 5 are disposed. The hot air is blown from the upper hot air blowing portion 45 to the opposite surface side (upper surface side) of the position where the hot air is blown. Similarly, since the six upper exhaust boxes 56 and the six lower exhaust boxes 55 are arranged to face each other across the transport path PL, the base material 5 on which gas suction by the lower exhaust box 55 is performed. Gas suction by the upper exhaust box 56 is also performed on the opposite side of the lower surface position. For this reason, hot air is blown from the upper and lower sides to the same position on the upper and lower surfaces of the base material 5 and gas suction is performed, so that the base material 5 can be prevented from being waved and stably transported. it can.

  By the way, in this embodiment, the hot air which passed the three ventilation boxes 25 in the preheating part 20 is guide | induced to the upper hot-air ejection part 45 of the drying part 40 with the air guide pipe 35. FIG. The upper hot air ejection part 45 blows hot air discharged from the ventilation part 23 of the ventilation box 25 onto the substrate 5. That is, the hot air is reused by directly blowing the hot air used to heat the ceramic plate 24 in the preheating unit 20 to emit infrared rays on the coating film of the substrate 5 in the drying unit 40. It is. For this reason, the increase in the hot air consumption as the total in the preheating part 20 and the drying part 40 can be suppressed.

  In the process of flowing through the air guide pipe 35 after passing through the three ventilation boxes 25, a temperature drop of hot air is inevitable. For this reason, the temperature of the hot air supplied from the hot air supply unit 27 to the ventilation unit 23 of the most upstream ventilation box 25 is set higher than the temperature of the hot air blown by the hot air ejection unit 31 to the base material 5. Specifically, the temperature of the hot air that is guided to the air guide pipe 35 and is blown from the upper hot air blowing portion 45 to the base material 5 is approximately the same as the temperature of the hot air that is blown from the lower hot air blowing portion 51 to the base material 5. The hot air supply part 27 should just supply the hot air of such temperature. In addition, the temperature of the hot air which the lower hot-air ejection part 51 blows on the base material 5 is about 50 ° C. to 300 ° C. which is the same as the temperature of the hot air which the hot-air ejection part 31 blows on the base material 5 (depending on the material of the coating film) To do).

  Next, FIG. 5 is a diagram showing a configuration of the annealing unit 60. The annealing unit 60 includes a lower hot air jet unit 61, an upper hot air jet unit 65, an upper exhaust box 66, and a lower exhaust box 69 inside a chamber 64 having openings formed at both ends. The annealing unit 60 includes a hot air supply unit 63 that supplies hot air to the lower hot air ejection unit 61 and a hot air supply unit 68 that supplies hot air to the upper hot air ejection unit 65.

  The chamber 64 is provided so as to surround the transport path PL through which the base material 5 is transported by the transport mechanism 80. Openings for allowing the substrate 5 to pass through are formed at both ends of the chamber 64. Inside the chamber 64, a plurality of lower hot air ejection portions 61 (three in the present embodiment) and a plurality of lower exhaust boxes 69 (four in the present embodiment) are based on the lower side of the transfer path PL. They are provided alternately along the conveying direction (X direction) of the material 5. Further, inside the chamber 64, a plurality of upper hot air ejection portions 65 (three in the present embodiment) and a plurality of upper exhaust boxes 66 (four in the present embodiment) are on the upper side of the transport path PL. 5 are alternately provided along the conveyance direction. The length of the chamber 64 of the annealing unit 60 is not particularly limited, but is about 2000 mm in this embodiment.

  Each of the three lower hot air ejection portions 61 provided on the lower side of the conveyance path PL has a plurality of ejection holes (not shown) facing upward, like the lower hot air ejection portion 51 of the drying unit 40. I have. The lower hot air ejection part 61 is connected in communication with a hot air supply part 63 via a pipe 62. The hot air supply unit 63 includes a heater and a blower, and supplies the heated air to the lower hot air jet unit 61 as hot air. The plurality of lower hot air ejection sections 61 eject the hot air fed from the hot air supply section 63 from the ejection holes toward the upper conveyance path PL.

  Each of the three upper hot air ejection parts 65 provided on the upper side of the transport path PL is the same as the upper hot air ejection part 45 of the drying unit 40. That is, each upper hot air ejection part 65 is configured by connecting an ejection head to a rectifying plate parallel to the transport path PL. Moreover, the ceramic plate which radiates | emits infrared rays by being heated is provided in the lower surface of the baffle plate of each upper side hot-air ejection part 65. As shown in FIG. However, in the annealing unit 60, the upper hot air ejection unit 65 is connected to the hot air supply unit 68 through a pipe 67. The hot air supply unit 68 includes a heater and a blower, and supplies the heated air as hot air to the upper hot air ejection unit 65. The plurality of upper hot air ejection sections 65 eject hot air supplied from the hot air supply section 68 toward the lower conveyance path PL.

  An upper exhaust box 66 is provided between upper hot-air ejection portions 65 arranged adjacent to each other along the conveyance direction (X direction) of the base material 5. Further, the upper exhaust box 66 is also provided at both ends of the arrangement of the upper hot air ejection portions 65. That is, four upper exhaust boxes 66 are provided for the three upper hot air ejection portions 65, and the upper exhaust boxes 66 are disposed at positions closest to the opening at both ends of the chamber 64. Each upper exhaust box 66 is the same as the upper exhaust box 56 of the drying unit 40 and is connected in communication with an exhaust unit (not shown).

  On the other hand, a lower exhaust box 69 is provided between the lower hot air ejection portions 61 arranged adjacent to each other along the transport direction of the base material 5. The lower exhaust box 69 is also provided at both ends of the array of the lower hot air ejection portions 61. That is, four lower exhaust boxes 69 are provided for the three lower hot air ejection portions 61, and the lower exhaust boxes 69 are disposed at positions closest to the opening at both ends of the chamber 64. Each lower exhaust box 69 is connected in communication with an exhaust unit (not shown).

  Similarly to the drying unit 40, the three upper hot air ejection units 65 and the three lower hot air ejection units 61 are arranged to face each other across the transport path PL, and the four upper exhaust boxes. 66 and four lower exhaust boxes 69 are arranged opposite to each other across the transport path PL. Accordingly, hot air is blown from the top and bottom at the same position on the upper and lower surfaces of the base material 5 and gas suction is performed, so that the transport of the base material 5 in the annealing unit 60 can be stabilized.

  The substrate 5 on which the electrode material coating film has been dried by the drying unit 40 is transported from the drying unit 40 toward the annealing unit 60 along the transport path PL by the transport mechanism 80. When the substrate 5 passes through the annealing part 60, the coating film is further heated by hot air jets from the upper hot air jet part 65 and the lower hot air jet part 61. That is, the base material 5 is directly heated by the lower hot air blowing part 61 to which the hot air is supplied from the hot air supply part 63 from below the base material 5, and the heat from the base material 5 is heated. The coating film of the electrode material is heated by conduction. The hot air blown to the lower surface of the base material 5 from the lower hot air jet part 61 is collected by the lower exhaust box 69 provided on both sides of the lower hot air jet part 61. Further, the upper hot air blowing section 65 to which hot air is supplied from the hot air supply section 68 blows hot air from above the base material 5, whereby the coating film is directly heated by the hot air. The temperature of the hot air blown to the base material 5 by the upper hot air blowing portion 65 and the lower hot air blowing portion 61 is higher than the temperature of the hot air blown by the upper hot air blowing portion 45 and the lower hot air blowing portion 51 of the drying unit 40.

  The hot air blown to the upper surface of the base material 5 from the upper hot air jet part 65 flows along the X direction between the current plate and the base material 5, and enters the exhaust box 66 provided on both sides of the upper hot air jet part 65. To be recovered. Since hot air flows between the current plate and the base material 5, the coating film formed on the base material 5 is kept in contact with the hot air with low humidity, and the coating film can be efficiently dried by heating. it can. Further, when hot air flows between the rectifying plate and the substrate 5, the ceramic plate provided on the lower surface of the rectifying plate is also heated. As a result, infrared rays are emitted from the heated ceramic plate and applied. The film is heated.

  The coating film of the electrode material formed on the base material 5 is heated from above and below by such hot air jets from the upper hot air jet part 65 and the lower hot air jet part 61 and further infrared radiation from the ceramic plate. As a result, the coating film is heated to a higher temperature than during the drying process, and the distortion and residual stress generated in the coating film by the drying process in the drying unit 40 are removed. Further, the organic solvent slightly remaining in the coating film is also completely evaporated. Even in the annealing unit 60, hot air is directly blown onto the coating film, but since hot air is blown onto the already dried coating film, there is no possibility of causing problems such as cracks due to rapid drying.

  Moreover, when the lower hot air ejection part 61 blows hot air upward from the lower side of the base material 5, a force that rises upward on the base material 5 acts by the wind pressure of the hot air. As a result, as in the preheating unit 20 and the drying unit 40, the lower hot air ejection unit 61 also plays an auxiliary role of the transport mechanism 80 for floatingly transporting the base material 5.

  Next, FIG. 6 is a diagram illustrating a configuration of the cooling unit 70. The cooling unit 70 cools the base material 5 after the drying process. The cooling unit 70 includes a lower cold air ejection unit 71, an upper cold air ejection unit 75, and an exhaust box 76 inside a chamber 74 having openings formed at both ends. The cooling unit 70 includes a cold air supply unit 73 that supplies normal temperature dry air to the lower cold air ejection unit 71 and a cold air supply unit 78 that supplies dry air to the upper cold air ejection unit 75.

  The chamber 74 is provided so as to surround the transport path PL through which the base material 5 is transported by the transport mechanism 80. Openings for allowing the substrate 5 to pass through are formed at both ends of the chamber 74. Inside the chamber 74, a plurality of lower cold air ejection portions 71 (three in the present embodiment) are provided below the conveyance path PL along the conveyance direction (X direction) of the base material 5. Further, inside the chamber 74, a plurality of upper cold air ejection portions 75 (three in the present embodiment) and a plurality of exhaust boxes 76 (four in the present embodiment) are disposed on the upper side of the conveyance path PL. Are alternately provided along the transport direction. The length of the chamber 74 of the cooling unit 70 is not particularly limited, but is about 1000 mm in this embodiment.

  Each of the three lower cold air ejection portions 71 provided on the lower side of the transport path PL is provided with a plurality of ejection holes, not shown, facing upward. The lower cold air ejection part 71 is connected in communication with a cold air supply part 73 via a pipe 72. The cold air supply unit 73 includes a blower and a dehumidifier, and supplies normal temperature dry air to the lower cold air ejection unit 71. The plurality of lower cold air ejection units 71 eject the dry air supplied from the cold air supply unit 73 from the ejection holes toward the upper conveyance path PL.

  On the other hand, the configuration of each of the three upper cold air ejection portions 75 provided on the upper side of the transport path PL is substantially the same as the configuration of the upper hot air ejection portion 45 of the drying unit 40. That is, each upper cold air ejection part 75 is configured by connecting an ejection head to a current plate parallel to the transport path PL. However, the ceramic plate is not provided in the upper cold air ejection part 75 of the cooling part 70. Further, in the cooling unit 70, an upper side cold air ejection unit 75 is connected to a cold air supply unit 78 through a pipe 77. The cold air supply unit 78 includes a blower and a dehumidifier, and supplies normal temperature dry air to the upper cold air ejection unit 75. The plurality of upper cold air ejection units 75 eject the dry air supplied from the cold air supply unit 78 toward the lower conveyance path PL.

  Moreover, the upper side cold wind ejection part 75 and the lower side cold wind ejection part 71 are arranged to face each other across the transport path PL. Thereby, a wind pressure will act on the same position of the upper and lower surfaces of the base material 5 from the upper and lower sides, and conveyance of the base material 5 in the cooling unit 70 can be stabilized.

  An exhaust box 76 is provided between the upper cold air ejection portions 75 arranged adjacent to each other along the conveyance direction (X direction) of the base material 5. Further, the exhaust boxes 76 are also provided at both ends of the array of the upper cold air ejection portions 75. That is, four exhaust boxes 76 are provided for the three upper cold air ejection portions 75. Each exhaust box 76 is the same as the exhaust box 56 of the drying unit 40.

  The substrate 5 that has been subjected to the heat treatment of the coating film of the electrode material from the preheating unit 20 to the annealing unit 60 is conveyed by the conveyance mechanism 80 from the annealing unit 60 toward the cooling unit 70 along the conveyance path PL. When the substrate 5 passes through the cooling unit 70, the high-temperature coating film is cooled by the dry air ejection from the upper side cold air ejection part 75 and the lower side cold air ejection part 71. That is, when the cold air blowing unit 71 to which the normal temperature dry air is supplied from the cold air supply unit 73 blows the dry air from below the base material 5, the base material 5 is directly cooled, and the base film 5 is removed from the coating film. The coating film is cooled by heat conduction in the material 5. Further, the upper cold air blowing section 75 to which the normal temperature dry air is supplied from the cold air supply section 78 blows the dry air from above the substrate 5, thereby directly cooling the coating film.

  The dry air blown to the upper surface of the base material 5 from the upper cold air ejection part 75 flows along the X direction between the current plate and the base material 5, and enters the exhaust box 76 provided on both sides of the upper cold air ejection part 75. Collected. Since dry air flows between the current plate and the base material 5, the coating film formed on the base material 5 is kept in contact with the dry air at room temperature, and the coating film can be efficiently cooled.

  The coating film of the electrode material formed on the substrate 5 by the dry air ejection from the upper side cold air ejection part 75 and the lower side cold air ejection part 71 is cooled from above and below, so that the coating after the drying process is performed. The temperature of the membrane drops rapidly. The flow rate of the dry air ejected from the upper cold air ejection part 75 and the lower cold air ejection part 71 may be a cooling rate that does not cause distortion in the coating film. In the cooling unit 70, it is not always necessary to cool the substrate 5 to room temperature, and it is sufficient to cool the substrate 5 to such an extent that the winding roller 82 can be wound.

  Further, when the lower cold air ejection part 71 blows dry air upward from below the base material 5, a force that rises upward on the base material 5 due to the wind pressure of the dry air acts. As a result, as in the preheating unit 20 to the annealing unit 60, the lower cold air ejection unit 71 also serves as an auxiliary function of the transport mechanism 80 for floatingly transporting the base material 5. The substrate 5 that has been subjected to the cooling process is wound up by a winding roller 82. After the formation of the coating film of the electrode material on one surface of the base material 5 is finished, the base material 5 is reversed and applied again from the unwinding roller 81 to the coating processing unit 10, the preheating unit 20, the drying unit 40, and the annealing unit. 60 and the cooling unit 70 may be conveyed in this order to form an electrode material coating film on the opposite surface.

  Next, waste heat recovery using the outer pipe 85 provided so as to cover the exhaust pipe 92 of the drying unit 40 will be described. FIG. 7 is a diagram showing a schematic configuration of the waste heat recovery system. As described above, the chamber 41 of the drying unit 40 that houses the base material 5 coated with the coating agent containing NMP, which is an organic solvent, is provided with the lower hot air ejection unit 51 and the lower exhaust box 55. Yes. The lower hot air ejection part 51 is connected in communication with a hot air supply part 53 via a pipe 52. The hot air supply unit 53 supplies hot air from the lower hot air ejection unit 51 into the chamber 41. The hot air blown to the lower surface of the base material 5 from the lower hot air ejection part 51 is collected by the lower exhaust box 55 provided on both sides of the lower hot air ejection part 51. Then, the hot air collected in the lower exhaust box 55 passes through an exhaust pipe 92 connected to the lower exhaust box 55 (that is, connected to the internal space of the chamber 41) and is exhausted as exhaust gas. It is discharged to 93.

  The exhaust gas flowing through the exhaust pipe 92 is exhausted from the atmosphere in the chamber 41, and has a high temperature and contains an organic solvent evaporated from the coating film of the substrate 5. From the viewpoint of energy saving, it is preferable to recover the heat of the high-temperature exhaust gas and reuse it. However, if the exhaust gas is circulated and used as a supply gas as it is, the organic solvent is also circulated. There is a possibility that the concentration of the organic solvent becomes higher than the limit value.

  For this reason, in the present embodiment, an outer pipe 85 is provided around the exhaust pipe 92. FIG. 8 is a cross-sectional view of the exhaust pipe 92 and the outer pipe 85 cut in the longitudinal direction. FIG. 9 is a view of the exhaust pipe 92 and the outer pipe 85 as seen from the AA cross section of FIG. The outer pipe 85 is a substantially cylindrical hollow tubular member that covers the exhaust pipe 92 so as to separate the space 99 from the outer wall of the cylindrical exhaust pipe 92. Both ends in the longitudinal direction of the outer tube 85 are opened, and the openings at both ends serve as outside air intake ports 85a and 85b. As shown in FIG. 8, the diameters of the intake ports 85 a and 85 b formed at both ends of the outer tube 85 are smaller than the inner diameter of the central portion of the outer tube 85.

  In addition, as shown in FIG. 9, a plurality of spacers 98 are sandwiched between the inner wall surface of the outer tube 85 and the outer wall surface of the exhaust pipe 92. The spacer 98 is a member for maintaining a constant distance between the inner wall surface of the outer pipe 85 and the outer wall surface of the exhaust pipe 92. The shape of the spacer 98 can be, for example, a cylindrical shape, but is not limited thereto, and may be another shape such as a quadrangular prism shape. In the present embodiment, the four spacers 98 are provided along the circumferential direction of the outer tube 85, but the present invention is not limited to this, and an arbitrary number can be used. Furthermore, spacers 98 may be provided at a plurality of locations along the longitudinal direction of the outer tube 85.

  The outer tube 85 includes a metal tube 852 and a heat insulating material 851. The heat insulating material 851 is covered on the outer wall of the metal tube 852. The reason why the inside of the outer tube 85 is the metal tube 852 is that the case where the atmosphere of the organic solvent leaks from the exhaust tube 92 is taken into consideration. The metal tube 852 may be formed of a metal having excellent heat resistance, such as stainless steel, but is not limited thereto, and may be formed of other metal materials such as an aluminum alloy. As the heat insulating material 851, for example, glass wool, silicon foam rubber or the like can be used.

  The exhaust pipe 92 is preferably formed of a metal material, such as an aluminum alloy, which has excellent heat resistance and resistance to organic solvents and has high thermal conductivity. The material of the exhaust pipe 92 is not limited to aluminum alloy, but may be formed of other metal materials such as stainless steel.

  Returning to FIG. 7, the space 99 formed between the outer wall of the exhaust pipe 92 and the inner wall of the outer pipe 85 and the hot air supply unit 53 are connected in communication by a circulation pipe 86. A blower 87 and a filter 88 are inserted in the middle of the path of the circulation pipe 86. An organic solvent detection sensor 89 is provided in the middle of the circulation pipe 86. The blower 87 blows gas along the flow path of the circulation pipe 86 from the space 99 between the exhaust pipe 92 and the outer pipe 85 toward the hot air supply unit 53. The filter 88 removes particles and the like from the gas flowing through the circulation pipe 86.

  The organic solvent detection sensor 89 detects the concentration of the organic solvent in the gas flowing through the circulation pipe 86. The detection result is transmitted from the organic solvent detection sensor 89 to the control unit 90. The control unit 90 controls the mechanism of each unit provided in the heat treatment system 1, and the hardware configuration is the same as that of a general computer. That is, the control unit 90 stores a CPU that performs various arithmetic processes, a ROM that is a read-only memory that stores basic programs, a RAM that is a readable and writable memory that stores various information, control software, data, and the like. It is configured with a magnetic disk. The processing in the heat treatment system 1 proceeds by the CPU of the control unit 90 executing a predetermined processing program.

  FIG. 10 is a cross-sectional view of the circulation pipe 86 cut in the longitudinal direction. The circulation pipe 86 may be formed of the same metal material as the metal pipe 852 of the outer pipe 85. A heat insulating material 861 is provided on the outer wall of the circulation pipe 86. As the heat insulating material 861 of the circulation pipe 86, for example, glass wool, silicon foam rubber or the like can be used.

  When the atmosphere in the chamber 41 is exhausted through the exhaust pipe 92, the blower 87 is operated to send gas from the space 99 between the exhaust pipe 92 and the outer pipe 85 toward the hot air supply unit 53. By operating the blower 87, negative pressure acts on the intake ports 85a and 85b at both ends of the outer tube 85, and external air is taken into the space 99 from the intake ports 85a and 85b. In the space 99 inside the outer pipe 85, heat exchange is performed between the hot exhaust gas flowing through the exhaust pipe 92 and the gas taken into the space 99 via the exhaust pipe 92. As a result, the temperature of the exhaust gas flowing through the exhaust pipe 92 decreases, and the temperature of the gas flowing through the space 99 increases.

  In the present embodiment, since the exhaust pipe 92 is formed of an aluminum alloy or stainless steel excellent in heat conduction, heat exchange between the exhaust gas flowing through the exhaust pipe 92 and the gas taken into the outer pipe 85 is performed. Can increase the efficiency. Further, since the diameters of the outside air intake ports 85a and 85b are smaller than the inner diameter of the central portion of the outer tube 85, the gas taken in near the both ends of the outer tube 85 becomes a turbulent flow. The heat exchange efficiency can be further increased. Furthermore, a spacer 98 provided to keep a constant distance between the inner wall surface of the outer pipe 85 and the outer wall surface of the exhaust pipe 92 is disposed in the space 99 inside the outer pipe 85, and the airflow flowing in the space 99 It also functions as a turbulent flow forming member that disturbs the flow to make turbulent flow. Thereby, the gas flowing through the space 99 also becomes a turbulent flow in the region inside the both ends of the outer pipe 85, and the heat exchange efficiency with the outer wall surface of the exhaust pipe 92 can be increased.

  The gas that has been taken in from the intake ports 85a and 85b and heated in the process of flowing through the space 99 inside the outer tube 85 through heat exchange with the exhaust gas flows into the circulation tube 86 and is sent out to the hot air supply unit 53 by the blower 87. It is. Since the outer tube 85 is configured by covering the outer wall of the metal tube 852 with a heat insulating material 851, heat dissipation from the gas heated by heat exchange is minimized, and the temperature of the gas in the space 99 is decreased. Can be prevented. Further, since the diameters of the outside air intake ports 85 a and 85 b are narrowed to be smaller than the inner diameter of the central portion of the outer tube 85, it is possible to suppress the gas heated in the space 99 from flowing out of the outer tube 85. Can do. Furthermore, since the heat insulating material 861 is also provided on the outer wall of the circulation pipe 86, it is possible to prevent the temperature of the gas that has been raised in the process of flowing through the outer pipe 85 from decreasing in the circulation pipe 86.

  The gas sent out to the circulation pipe 86 passes through the filter 88, thereby removing particles and the like and increasing the cleanliness. The concentration of the organic solvent in the gas flowing through the circulation pipe 86 is detected by the organic solvent detection sensor 89 and transmitted to the control unit 90.

  The gas fed from the circulation pipe 86 to the hot air supply unit 53 is reheated to a predetermined temperature by the heater of the hot air supply unit 53, passes through the pipe 52, and enters the chamber 41 from the lower hot air ejection unit 51 of the drying unit 40. Supplied. The hot air ejected from the lower hot air ejection part 51 is collected by the lower exhaust box 55 and discharged to the exhaust pipe 92, and the same heat exchange as described above is repeated.

  If it does in this way, the thermal energy of the high temperature exhaust gas discharged | emitted from the chamber 41 will be collect | recovered, the gas newly taken in from the intake ports 85a and 85b of the outer pipe | tube 85 will be heated, and the temperature-raised gas will be supplied with hot air Since it is used as hot air supplied to the unit 53 and supplied to the chamber 41, heating by the heater of the hot air supply unit 53 can be reduced compared to raising the temperature of the ambient air to hot air, and energy consumption Can be suppressed. As a result, the energy consumption efficiency in the drying unit 40 and the heat treatment system 1 incorporating the drying unit 40 can be made excellent.

  The outer pipe 85 is provided so as to separate the outer wall of the exhaust pipe 92 and the space 99, and the atmosphere is completely separated from the space 99 and the internal flow path of the exhaust pipe 92 by the pipe wall of the exhaust pipe 92. Therefore, the exhaust gas flowing inside the exhaust pipe 92 and the outside air taken into the outer pipe 85 are not mixed with each other, and the vapor of the organic solvent is generated in the gas fed from the circulation pipe 86 to the hot air supply unit 53. Mixing is prevented. As a result, an increase in the concentration of the organic solvent in the hot air supplied from the hot air supply unit 53 to the chamber 41 can be suppressed.

  If exhaust gas containing an organic solvent discharged from the chamber 41 due to deterioration of the exhaust pipe 92 or the like is mixed into the space 99 inside the outer pipe 85, it goes from the circulation pipe 86 to the hot air supply unit 53. The concentration of the organic solvent in the gas increases. The concentration of the organic solvent in the gas flowing through the circulation pipe 86 is sequentially detected by the organic solvent detection sensor 89 and transmitted to the control unit 90. When the concentration of the organic solvent detected by the organic solvent detection sensor 89 exceeds a preset warning threshold value (first set value), the control unit 90 issues a warning. For example, under the control of the control unit 90, a warning sound is emitted, a warning light is turned on, a warning message is displayed on the monitor, and the like.

  When the organic solvent concentration detected by the organic solvent detection sensor 89 exceeds a preset stop threshold (second set value), the control unit 90 stops the drying unit 40 or the entire heat treatment system 1. These warning threshold value and stop threshold value are stored in the storage unit of the control unit 90 in advance. The stop threshold is larger than the warning threshold. For example, if the organic solvent is NMP, the stop threshold can be 0.6 vol% and the warning threshold can be 0.25 vol%.

  Thus, by monitoring the organic solvent concentration in the gas flowing through the circulation pipe 86 by the organic solvent detection sensor 89, it is possible to suppress an increase in the concentration of the organic solvent in the hot air supplied to the chamber 41. Even if the organic solvent vapor leaks from the exhaust pipe 92 into the space 99, the organic solvent concentration in the gas flowing through the circulation pipe 86 is measured by the organic solvent detection sensor 89, and the measured value increases. At times, warnings and equipment stoppages are taken step by step, so explosions and fires can be reliably prevented.

  While the embodiments of the present invention have been described above, the present invention can be modified in various ways other than those described above without departing from the spirit of the present invention. For example, in the above-described embodiment, heat exchange is performed using the high-temperature exhaust gas discharged from the lower exhaust box 55 of the drying unit 40, but the other parts in the preheating unit 20, the drying unit 40, and the annealing unit 60 are used. Waste heat recovery may be performed from the exhaust gas discharged from the exhaust box in the same manner as in the above embodiment. However, since the hot air that has passed through the ventilation box 25 in the preheating unit 20 is supplied to the upper hot air jetting unit 45 of the drying unit 40, the heat recovered from the exhaust gas discharged from the upper exhaust box 56 of the drying unit 40. The gas heated by the above may be supplied to the hot air supply unit 27 of the preheating unit 20.

  In the above embodiment, the intake ports 85a and 85b are provided at both ends of the outer tube 85. However, one end of the outer tube 85 is closed and only the other end is opened to form an external air intake port. May be. However, the efficiency of heat exchange in the outer pipe 85 is governed by the temperature difference between the temperature of the exhaust gas flowing inside the exhaust pipe 92 and the temperature of the gas in the space 99 in contact with the outer wall of the exhaust pipe 92, and the temperature difference is large. The efficiency of heat exchange increases. From this point of view, as in the above-described embodiment, when the intake ports 85a and 85b are provided at both ends of the outer tube 85, the region in which the temperature difference between the outside air and the exhaust gas increases is increased, so the efficiency of heat exchange is increased. Becomes higher.

  In the above embodiment, the spacer 98 for keeping the space between the inner wall surface of the outer pipe 85 and the outer wall surface of the exhaust pipe 92 has a role of disturbing the airflow flowing through the space 99 and making it turbulent. However, instead of or in combination with this, a dedicated turbulent flow forming member may be provided in the space 99. As such a turbulent flow forming member, for example, a protrusion may be provided on the inner wall surface of the outer tube 85.

  Further, the shape of the outer tube 85 is not limited to a straight tube shape, and may be set along the shape of the exhaust tube 92. For example, when the exhaust pipe 92 is bent and disposed, the shape of the outer pipe 85 may be bent accordingly. Further, when a plurality of exhaust pipes 92 are provided corresponding to the plurality of lower exhaust boxes 55 as in this embodiment, an outer pipe 85 may be provided for each exhaust pipe 92. good. Further, in the case where a plurality of exhaust pipes 92 are provided, a box-shaped member that covers the entirety of them may be provided instead of the outer pipe 85.

  In the above embodiment, the hot air used to heat the ceramic plate 24 in the preheating unit 20 is supplied to the upper hot air ejection unit 45 of the drying unit 40 and reused. Similarly to 60, a dedicated hot air supply unit may be provided in the upper hot air ejection unit 45, and hot air may be supplied from there to the upper hot air ejection unit 45. In this case, the gas heated by the heat recovered from the exhaust gas discharged from the upper exhaust box 56 of the drying unit 40 is supplied to the dedicated hot air supply unit to the upper hot air ejection unit 45.

  Further, the number of the upper hot air ejection part 45, the upper exhaust box 56, the lower hot air ejection part 51, and the lower exhaust box 55 provided in the drying part 40 is not limited to the example of the above embodiment, and the drying part 40 Depending on the length, etc., it may be appropriate. Similarly, the number of wind blowing parts provided in the annealing part 60 and the cooling part 70 is not limited to the example of the above embodiment, and may be appropriate.

  Further, in the heat treatment system 1 of the above-described embodiment, three zones (the preheating unit 20, the drying unit 40, and the annealing unit 60) for heating the coating film of the electrode material formed on the substrate 5 are provided. However, the annealing part 60 is not necessarily an essential element from the viewpoint of the drying treatment of the coating film. For example, if the material of the coating film is such that almost no distortion or the like occurs during the drying process, the drying apparatus that performs the drying process of the coating film only needs to include the preheating unit 20 and the drying unit 40.

  Further, the coating film to be subjected to the drying treatment using the technology according to the present invention is not limited to the electrode material film of the lithium ion secondary battery, and for example, a solar cell material (electrode material, sealing material) Or an insulating film or a protective film made of an electronic material. The technique according to the present invention can be suitably applied to dry a coating film in which a material having a relatively high viscosity is thickly applied. Therefore, the technique according to the present invention may be used to dry the coating film of the pigment or the adhesive.

DESCRIPTION OF SYMBOLS 1 Heat processing system 5 Base material 10 Coating process part 11 Coating nozzle 20 Preheating part 21,41,64,74 Chamber 23 Ventilation part 24,42 Ceramic plate 25 Ventilation box 27,33,53,63,68 Hot-air supply part 35 Air guide pipe 40 Drying section 43 Current plate 45, 65 Upper hot air ejection section 46 Ejection head 51, 61 Lower hot air ejection section 55, 69 Lower exhaust box 56, 66 Upper exhaust box 57, 92 Exhaust pipe 58, 93 Exhaust section 60 Annealing part 70 Cooling part 80 Conveying mechanism 83a to 83e Auxiliary roller 85 Outer pipe 85a, 85b Intake port 86 Circulating pipe 87 Blower 88 Filter 89 Organic solvent detection sensor 90 Control part 98 Spacer 99 Space 851, 861 Heat insulating material 852 Metal pipe PL Transport route

Claims (10)

A drying device that performs a drying process on a substrate coated with a coating agent containing an organic solvent,
A chamber containing a substrate;
Hot air supply means for supplying hot air into the chamber;
An exhaust pipe connected to the chamber and exhausting the atmosphere in the chamber;
An outer pipe that includes an outside air intake port and covers the exhaust pipe so as to separate the outer wall of the exhaust pipe and a space;
A circulation pipe that communicates and connects a space formed between an outer wall of the exhaust pipe and an inner wall of the outer pipe and the hot air supply means;
Blower means provided in the course of the circulation pipe, and blows gas from the space toward the hot air supply means;
An organic solvent detecting means provided in the course of the circulation pipe for detecting the concentration of the organic solvent in the gas flowing through the circulation pipe;
A drying apparatus comprising: The drying apparatus according to claim 1, wherein
A drying device, wherein an outside air intake port is formed at each of both ends of the outer tube. The drying apparatus according to claim 2, wherein
The drying apparatus characterized in that a diameter of the intake port formed at each of both ends of the outer tube is smaller than an inner diameter of a central portion of the outer tube. In the drying apparatus in any one of Claims 1-3,
A drying apparatus, wherein a turbulent flow forming member that disturbs an airflow flowing through the space inside the outer pipe to form a turbulent flow is disposed in the space. The drying apparatus according to any one of claims 1 to 4,
When the organic solvent concentration detected by the organic solvent detecting means exceeds the first set value, a warning is issued, and when the second set value larger than the first set value is exceeded, the drying apparatus is stopped. A drying apparatus, further comprising a control means. In the drying apparatus in any one of Claims 1-5,
The outer tube includes a metal tube and a heat insulating material coated on an outer wall of the metal tube. The drying apparatus according to any one of claims 1 to 6,
A drying apparatus, wherein a heat insulating material is provided on an outer wall of the circulation pipe. The drying apparatus according to any one of claims 1 to 7,
A drying apparatus comprising a filter in the middle of the circulation pipe. The drying apparatus according to any one of claims 1 to 8,
The drying apparatus is characterized in that the exhaust pipe is formed of aluminum alloy or stainless steel. A coating processing unit that forms a coating film by applying a coating agent on a substrate;
A preheating part for preheating the coating film;
A drying apparatus according to any one of claims 1 to 9,
A cooling unit for cooling the substrate after the drying treatment;
A heat treatment system comprising:

Images