JP2014035086A - Drying furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drying furnace capable of suppressing outflow of atmospheric gas to the outside more efficiently.SOLUTION: An internal gas outflow preventing part 80 is provided in a carrying-in path 19 for transporting a sheet 50 from the outside to an opening 17 of a drying furnace body part 14. The internal gas outflow preventing part 80 is disposed above the sheet and has first to third compartment spaces 76 to 78 as inclined spaces of which upper parts are inclining away from the drying furnace body part 14, and supplies a fluid of a temperature lower than the atmospheric gas in the opening 17 to the carrying-in path 19 as an inflow wind. The inflow wind flows through the carry-in path 19 in the direction of inflow to the drying furnace body part 14, and is supplied such that it flows along the upper surface of the sheet 50 toward below the internal gas outflow preventing part 80. Thus the atmospheric gas flowing out to carrying-in path 19 from the opening 17 along the upper surface of the sheet 50 is prevented from flowing out to the outside more efficiently.

Description

  The present invention relates to a drying furnace.

  Conventionally, as a heating device for heating an object to be heated, a heating apparatus including a heating main body part for heating the object to be heated and a conveyance path for conveying the object to be heated to or from the heating main body part is known. (For example, Patent Document 1). In this heating apparatus, an outside air inflow prevention portion that is inclined in a direction away from the heating main body portion and has a cavity formed therein is provided in the conveyance path. By providing this outside air inflow prevention part, it is said that the gas in the heating main body part having a temperature higher than that of the outside air can flow promptly along the partition walls of the outside air inflow prevention part and the inflow of outside air can be suppressed. It is also said that there is an effect of suppressing the outflow of gas to the outside air.

  Conventionally, a drying furnace is known in which a sheet such as a film on which a coating film to be dried is formed is continuously conveyed and dried (for example, Patent Document 2). In this drying furnace, a coating film containing ceramic powder, metal powder, an organic binder, and an organic solvent is formed on the surface of the base film, and this is continuously conveyed to the drying furnace for drying. In addition, by performing both infrared irradiation with an infrared heater and cooling air blowing to the coating film, the thermal expansion and subsequent contraction of the base film due to drying are suppressed, and deformation due to the stress of the coating film is suppressed. Yes.

JP 2008-128544 A Japanese Patent No. 4956696

  By the way, in a drying furnace like patent document 2, since a sheet | seat is continuously conveyed in a furnace, the entrance and exit of this sheet | seat cannot be blocked completely. For this reason, there has been a problem that the atmospheric gas containing the organic solvent volatilized from the coating film by drying flows out of the furnace from the entrance / exit along the upper surface of the sheet, thereby deteriorating the environment outside the furnace. In addition, there is a demand for suppressing the outflow of atmospheric gas to the outside of the furnace because there are many cases where it is not preferable to flow the gas generated from the coating film by drying to the outside of the furnace. Here, it is also conceivable to provide the outside air inflow prevention portion described in Patent Document 1 at the entrance and the like of the drying furnace to suppress the outflow of the atmospheric gas. However, the main purpose of the outside air inflow prevention part described in Patent Document 1 is to prevent outside air from flowing in, and the effect of suppressing the outflow of atmospheric gas to the outside is not sufficient.

  The present invention has been made to solve such a problem, and has as its main object to provide a drying furnace that can further suppress the outflow of atmospheric gas to the outside.

The drying furnace of the present invention is
A drying furnace that continuously transports a sheet on which a film to be dried is formed on the upper surface and performs drying,
A drying body for drying the membrane;
A conveyance path for carrying the sheet from the outside into the opening of the drying main body or carrying it out from the opening;
An inside air outflow prevention unit provided with an opening in the conveyance path, located above the sheet, and having an inclined space inclined in a direction in which an upper part is away from the drying main body unit;
Inflow air supply means for supplying a fluid having a temperature lower than the atmospheric gas in the opening to the transport path as inflow air;
With
The inflow air supply means supplies the inflow air so as to flow through the conveyance path in a direction of flowing into the drying furnace main body, and to flow under the inside air outflow prevention unit along the upper surface of the sheet.
Is.

  In the drying furnace according to the present invention, the inside air outflow prevention unit is provided in the conveyance path for carrying the sheet from the outside into the opening of the drying main body or carrying it out from the opening. The inside air outflow prevention portion is located above the seat and has an inclined space inclined in a direction in which the upper portion is away from the drying main body portion. Then, a fluid having a temperature lower than that of the atmospheric gas in the opening is supplied to the transport path as an inflow air. The inflow air is supplied so as to flow through the conveyance path in the direction of flowing into the drying furnace main body, and to flow below the inside air outflow prevention unit along the upper surface of the sheet. In this way, when there is an atmospheric gas flowing out from the opening along the upper surface of the sheet to the conveyance path, a cooler inflow air is submerged below the atmospheric gas below the inside air outflow prevention unit. As a result, the inflow air pushes up the atmospheric gas to the inside air outflow prevention portion so as to strip off the atmospheric gas from the upper surface of the sheet. Thereby, it can suppress that atmospheric gas passes a conveyance path. That is, the outflow of atmospheric gas to the outside can be further suppressed. In this case, an exhaust unit that exhausts the fluid in the inclined space of the internal air outflow prevention unit may be provided. In this way, the atmospheric gas in the internal air outflow prevention unit can be exhausted, so that the outflow of the atmospheric gas to the outside can be further suppressed. Further, the film may include ceramic powder or metal powder, an organic binder, and an organic solvent or water. The sheet may be a PET film. The atmosphere gas is not particularly limited, and examples thereof include air and an inert gas (such as nitrogen).

  In the drying furnace of the present invention, the inflow air supply means may supply the inflow air so as to pass below the inside air outflow prevention portion. In this way, the force of the inflowing air stripping off the atmospheric gas and pushing it up toward the inside air outflow prevention portion becomes stronger, so that the outflow of the atmospheric gas to the outside can be further suppressed.

  The drying furnace of the present invention includes an infrared heater provided in the drying main body, and the inflow air supply means passes under the inside air outflow prevention portion and reaches the drying main body from the opening. Alternatively, the inflow air may be supplied to cool the upper surface of the sheet. If it carries out like this, while drying a film | membrane with the infrared rays from an infrared heater, a film | membrane and a sheet | seat can be cooled with an inflow wind, and high temperature can be suppressed. Thereby, the thermal expansion at the time of drying of a sheet | seat and subsequent contraction can be suppressed, and it can suppress that a film | membrane deform | transforms with stress. Thus, the inflow air can serve both as a role of further suppressing the outflow of the atmospheric gas to the outside and a role of cooling the film. Note that the infrared heater may dry the film using electromagnetic waves having a peak wavelength in the near infrared region (for example, a region having a wavelength of 0.7 to 3.5 μm). Near-infrared rays can efficiently cut hydrogen bonds in molecules such as water and solvents in the object to be heated, so that the object to be dried can be efficiently dried. Moreover, when a sheet | seat consists of PET films, since a PET film is hardly heated with the infrared rays whose wavelength is 3.5 micrometers or less, a film | membrane can be dried, without heating a PET film. As such an infrared heater, for example, the outer circumference of the filament is concentrically covered by a plurality of tubes functioning as a filter that absorbs infrared rays having a wavelength exceeding 3.5 μm, and the surface temperature of the infrared heater is between these tubes. In this case, a cooling fluid flow path that suppresses the increase in the temperature (see Japanese Patent No. 4790092) may be used.

  In this case, the internal air supply means for supplying the internal air along the upper surface of the sheet from one of the carry-in side or the carry-out side of the sheet to the other in the drying main body portion to cool the upper surface of the sheet The inflowing air supply means may supply the inflowing air into the drying main body in a direction opposite to the internal airflow. By doing so, the film or sheet can be cooled by the internal wind, and deformation of the film can be further suppressed. And since inflow air is supplied in the direction opposite to internal wind, compared with the case where direction is the same, the outflow of atmospheric gas to the exterior by internal wind can be suppressed more, for example. In addition, you may supply internal air, for example, normal temperature or cold air of 50 degrees C or less.

  In this case, the internal air supply means supplies the internal air from the carry-out side of the sheet toward the carry-in side, and the internal air outflow prevention unit carries the sheet from the outside into the drying main body unit. And the inflow air supply means flows in the carry-in path in a direction to flow into the drying furnace main body, and passes under the inside air outflow prevention portion along the upper surface of the sheet to enter the inside of the drying main body. It is good also as what supplies the said inflow wind so that it may reach | attain. By so doing, the internal wind is supplied in the direction opposite to the sheet conveyance direction, so that the relative speed of the internal wind with respect to the sheet increases and the cooling effect on the upper surface of the sheet is enhanced.

  In the drying furnace of the present invention, the inflow air supply means flows in the conveyance path so as to be inclined toward the upper surface of the sheet with respect to the conveyance direction of the sheet, and then along the upper surface of the sheet. The inflow air may be supplied so as to flow downward of the inside air outflow prevention unit. If it carries out like this, inflow will have the flow which goes to the down from the upper side in the outside rather than the inside air outflow prevention part in a conveyance path. Therefore, the conveyance path can be blocked by the inflow air, and the outflow of the atmospheric gas to the outside can be further suppressed.

  In this case, a partition structure having a plurality of partition spaces inclined in a direction in which the upper part is away from the drying main body along the sheet conveying direction is provided, and the inflow air supply means is provided in the drying main body. In contrast, the passage has an inclined path that is inclined in a direction away from the upper portion, and the inflow air flows through the inclined path toward the upper surface of the sheet while being inclined in the conveying path with respect to the conveying direction of the sheet. In the partition structure, one or more of the plurality of partition spaces on the drying main body side is the inclined space of the inside air outflow prevention unit, and the plurality of partition spaces are opposite to the drying main body unit. One or more of the sides may be the inclined path of the inflow air supply means. If it carries out like this, the inclination space of an inside air outflow prevention part and the inclination path | route of an inflow wind supply means can be put together into one division structure. Therefore, the drying furnace provided with the inside air outflow prevention part and the inflow air supply means can be manufactured more easily.

  In the drying furnace of the present invention, the inflow air supply means flows horizontally along the upper surface of the sheet from the end opposite to the drying main body portion in the conveyance path so as to go to the drying main body portion. The inflow air may be supplied.

1 is a longitudinal sectional view of a drying furnace 10. FIG. 2 is a longitudinal sectional view of an infrared heater 30. FIG. It is AA sectional drawing of FIG. It is a longitudinal cross-sectional view of the drying furnace 110 of the modification. It is a longitudinal cross-sectional view of the drying furnace 210 of the modification.

  Next, a preferred embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of the drying furnace 10. The drying furnace 10 performs drying of the coating film 52 applied on the sheet 50 using infrared rays and cold air. The drying main body 14, the carry-in path 19, the internal air supply device 20, and internal air intake air. The apparatus 25, the infrared heater 30, and the controller 60 are provided. Further, the drying furnace 10 includes a partition structure 70, an inside air outflow prevention unit 80, an exhaust device 81, and an inflow air supply device 90. The drying furnace 10 includes a roll 54 provided on the left side of the carry-in path 19 and a roll 56 provided on the right side of the drying main body 14. The drying furnace 10 is configured as a so-called roll-to-roll type drying furnace in which a sheet 50 having a coating film 52 to be dried formed thereon is continuously transported by rolls 54 and 56 and dried. .

  The drying main body 14 is a heat insulating structure formed in a substantially rectangular parallelepiped shape, and has openings 17 and 18 on the front end face 15 and the rear end face 16, respectively. The opening 17 is an opening when the sheet 50 is carried into the drying main body 14 from the outside via the carry-in path 19. The drying main body 14 has a length from the front end face 15 to the rear end face 16 of, for example, 1 m to 6 m.

  The carry-in path 19 is a conveyance path for carrying the sheet 50 from the outside into the opening 17 of the drying main body 14 and is configured as a pipe line. The sheet 50 coated with the coating film 52 on one side is loaded from the loading port 19a on the opposite side of the drying main body 14 in the loading path 19 with the surface coated with the coating film 52 facing up. Subsequently, the sheet 50 passes through the carry-in path 19, reaches the opening 17, and is carried into the drying main body 14 from the opening 17. Then, the sheet 50 proceeds in the horizontal direction inside the drying main body 14 and is carried out from the opening 18.

The internal air supply device 20 is a device that cools the coating film 52 that passes through the inside of the drying main body portion 14 by blowing internal air that is cold air. The internal wind supply device 20 includes an air supply fan 21, a pipe structure 22, and an air supply nozzle 23. The air supply fan 21 is attached to the pipe structure 22 and supplies the internal wind to the inside of the pipe structure 22. The internal wind is, for example, room temperature or air of 50 ° C. or lower. The air supply fan 21 can adjust the air volume of the generated internal wind. Air volume of cold air is not particularly limited and can be adjusted in the range of, for example, 5Nm ³ / h~100Nm ³ / h. The pipe structure 22 serves as an internal wind passage from the air supply fan 21. The pipe structure 22 forms a passage from the air supply fan 21 through the ceiling of the drying main body 14 to the inside of the drying main body 14. The air supply nozzle 23 serves as a supply port for internal air from the air supply fan 21. The air supply nozzle 23 is provided at an end of the drying main body 14 on the opening 18 side which is the carry-out side of the sheet 50 and opens toward the opening 17 side which is the carry-in side. Thereby, the internal wind supply device 20 supplies the internal wind from the carry-out side of the sheet 50 toward the carry-in side (to the left in FIG. 1). The internal wind flows along the upper surface of the sheet 50 and cools the upper surface of the sheet 50, as indicated by the filled arrows in the drying main body 14 in FIG.

  The internal wind intake device 25 is a device that discharges the atmospheric gas in the drying main body 14. The internal wind intake device 25 includes an exhaust fan 26, a pipe structure 27, and an exhaust nozzle 28. The exhaust nozzle 28 serves as an exhaust port for internal wind from the internal wind supply device 20. The exhaust nozzle 28 is provided at an end of the drying main body 14 on the opening 17 side that is the carry-in side of the sheet 50, and opens toward the opening 18 that is the carry-out side. The exhaust nozzle 28 is attached to the pipe structure 27, and sucks atmospheric gas (mainly internal air after drying the sheet 50) in the drying main body 14 and guides it into the pipe structure 27. The pipe structure 27 serves as a flow path for the atmospheric gas from the exhaust nozzle 28 to the exhaust fan 26. The pipe structure 27 forms a passage from the exhaust nozzle 28 through the ceiling of the drying main body 14 to the exhaust fan 26 outside the drying main body 14. The exhaust fan 26 is attached to the pipe structure 27 and exhausts the atmospheric gas inside the pipe structure 27. The exhaust fan 26 is connected to an exhaust pipe (not shown), for example, and after performing an appropriate process such as removing a component such as a volatilized organic solvent contained in the atmospheric gas in the drying main body 14. The atmosphere gas is exhausted outside the drying furnace 10. Further, the exhaust fan 26 may circulate the atmospheric gas in the pipe structure 27 as the intake air of the air supply fan 21 without exhausting it outside the drying furnace 10.

  The infrared heater 30 is a device that irradiates infrared rays and dries the coating film 52 that passes through the drying furnace 10, and a plurality of infrared heaters 30 are attached near the ceiling of the drying main body 14. FIG. 2 is a longitudinal sectional view of the infrared heater 30, and FIG. 3 is a sectional view taken along the line AA of FIG. As shown in FIGS. 2 and 3, the infrared heater 30 includes a heater body 38 formed so that the inner tube 36 surrounds the filament 32, an outer tube 40 formed so as to surround the heater body 38, and an outer tube 40. A bottomed cylindrical cap 42 that is airtightly fitted to both ends of the tube 40, a flow path 48 that is formed between the heater body 38 and the outer tube 40, and through which the cooling fluid can flow, and a surface temperature of the outer tube 40. And a temperature sensor 37 for detection. The filament 32 is supplied with electric power from the electric power supply source 62 and is electrically heated to, for example, 700 to 1500 ° C., and emits infrared rays having a peak at a wavelength of 3.5 μm or less (for example, around 3 μm). The electric wiring 34 connected to the filament 32 is drawn out to the outside airtightly through a wiring drawing portion 44 provided in the cap 42, and is connected to the power supply source 62. The inner tube 36 is made of quartz glass, borosilicate crown glass, or the like, and functions as a filter that passes infrared rays having a wavelength of 3.5 μm or less and absorbs infrared rays having a wavelength exceeding 3.5 μm. The heater body 38 is supported at both ends by holders 49 disposed inside the cap 42. As with the inner tube 36, the outer tube 40 is made of quartz glass, borosilicate crown glass, or the like, and passes through infrared rays having a wavelength of 3.5 μm or less and absorbs infrared rays having a wavelength exceeding 3.5 μm. Function. Each cap 42 has a fluid inlet / outlet 46. In the channel 48, the cooling fluid supplied from the cooling fluid supply source 64 flows from one fluid inlet / outlet 46 to the other fluid inlet / outlet 46. The cooling fluid flowing through the flow path 48 is, for example, air or an inert gas, and cools the tubes 36 and 40 by contacting the inner tube 36 and the outer tube 40 and taking heat away. In the infrared heater 30, when infrared rays having a peak at a wavelength of 3.5 μm or less are radiated from the filament 32, infrared rays having a wavelength of 3.5 μm or less pass through the inner tube 36 and the outer tube 40 and pass through the conveyance path. The coating film 52 of the passing sheet 50 is irradiated. Infrared light having this wavelength is said to be excellent in the ability to break the hydrogen bond of the solvent contained in the coating film 52 of the sheet 50, and can efficiently evaporate the solvent. On the other hand, the inner tube 36 and the outer tube 40 absorb infrared rays having a wavelength exceeding 3.5 μm, but are cooled by the cooling fluid flowing through the flow path 48, and therefore, have a temperature below the ignition point of the solvent evaporating from the coating film 52 ( For example, it can be maintained at 200 ° C. or lower.

  As shown in FIG. 1, the partition structure 70 has an outer wall 72 and an inner wall 74. The outer wall 72 constitutes a surface on the drying main body 14 side, a surface on the carry-in port 19a side, and an upper surface of the partition structure 70. Of the outer wall 72, the surface on the drying main body 14 side and the surface on the carry-in entrance 19 a are inclined in a direction in which the upper portion is away from the drying main body 14. A plurality (three in FIG. 1) of inner walls 74 are arranged along the conveyance direction of the sheet 50, and all of them are inclined in a direction in which the upper part is away from the drying main body 14. The partition structure 70 has first to fourth partition spaces 76 to 79 in which a space in the outer wall 72 is partitioned by three inner walls 74. The first to fourth partition spaces 76 to 79 are arranged along the conveyance direction of the sheet 50, and the first partition space 76, the second partition space 77, the third partition space 78, the first partition space 76 from the side close to the drying main body 14. A four-compartment space 79 is provided. Each of the first to fourth partition spaces 76 to 79 is a space that is inclined in a direction in which the upper part is away from the drying main body portion 14, and is inclined by the same angle θ. The inclination angle θ may be greater than 0 ° and less than 90 °. Although not particularly limited, for example, the angle θ may be 30 to 60 °. As for the 1st-4th division space 76-79, the upper direction and the downward direction are respectively open. Below the first to fourth partition spaces 76 to 79 are opened in the carry-in path 19. Further, the pipe structures 83 are opened above the first to third partition spaces 76 to 78. An upper portion of the fourth partition space 79 opens into the pipe structure 92.

  The inside air outflow prevention unit 80 is provided so as to be opened in the conveyance path 19, is located above the sheet 50, and has an inclined space that is inclined in a direction in which the upper part is away from the drying main body unit 14. In the present embodiment, the inclined space of the inside air outflow prevention unit 80 is configured by first to third partition spaces 76 to 78. That is, among the first to fourth partition spaces 76 to 79 of the partition structure 70, three on the drying main body 14 side are inclined spaces of the inside air outflow prevention unit 80.

  The exhaust device 81 is a device that exhausts the atmospheric gas in the inside air outflow prevention unit 80. The exhaust device 81 includes an exhaust fan 82 and a pipe structure 83. The pipe structure 83 is branched into three from the exhaust fan 82 toward the first to third partition spaces 76 to 78. The pipe structure 83 is attached to the upper opening of the inside air outflow prevention unit 80, that is, the upper opening of the first to third partition spaces 76 to 78, and the exhaust fan 82 and the first to third partition spaces 76 to 78 are connected. It becomes the flow path of the atmospheric gas between. The exhaust fan 82 is the same as the exhaust fan 26, and discharges the atmospheric gas in the inside air outflow prevention unit 80 through the pipe structure 83.

The inflow air supply device 90 is a device that supplies a fluid having a temperature lower than the atmospheric gas in the opening 17 to the transport path 19 as inflow air. The inflow air supply device 90 includes an air supply fan 91, a pipe structure 92, and a fourth partition space 79 as an inclined path that is inclined in a direction in which the upper part is away from the drying main body. That is, one of the first to fourth partition spaces 76 to 79 of the partition structure 70 on the side opposite to the drying main body 14 is an inclined path of the inflow air supply device 90. The air supply fan 91 is attached to the pipe structure 92 and supplies the inflow air into the pipe structure 92. The inflow air may be at a temperature lower than the atmospheric gas in the opening 17 when the sheet 50 is dried, for example, air at normal temperature. The supply fan 91 is capable of adjusting the amount of inflow air to be generated. Flow rate of inlet airflow is not particularly limited and can be adjusted in the range of, for example, 5Nm ³ / h~100Nm ³ / h. The pipe structure 92 forms a passage of inflow air from the air supply fan 91 to the upper opening of the fourth partition space 79. As described above, the fourth partitioned space 79, which is the inclined path of the inflow air supply device 90, is inclined in a direction in which the upper part is away from the drying main body 14, and the inclination angle is an angle θ. The inflow air from the air supply fan 91 passes through the fourth partition space 79, and is supplied toward the upper surface of the sheet 50 while being inclined with respect to the conveyance direction of the sheet 50 in the conveyance path 19. Thereafter, the inflow air flows along the upper surface of the seat 50 to below the inside air outflow prevention unit 70. The inflow air passes below the inside air outflow prevention unit 80 and reaches the drying main body 14 from the opening 17 to cool the upper surface of the sheet 50 in the drying main body 14. In FIG. 1, the flow of the incoming air is indicated by white arrows. As shown in the figure, the direction of the incoming air is opposite to the direction of the internal air.

  The controller 60 is configured as a microprocessor centered on a CPU. The controller 60 outputs control signals to the air supply fan 21 of the internal air supply device 20 and the air supply fan 91 of the inflow air supply device 90 to individually control the air volume of the internal air and the inflow air. The controller 60 outputs control signals to the exhaust fan 26 of the internal wind intake device 25 and the exhaust fan 82 of the exhaust device 81 to individually control the exhaust amount. The controller 60 inputs the temperature of the outer pipe 40 detected by the temperature sensor 37 which is a thermocouple, and the on-off valve 66 and the flow rate adjustment provided in the middle of the pipe connecting the cooling fluid supply source 64 and the fluid inlet / outlet 46. A control signal is output to the valve 68 to individually control the flow rate of the cooling fluid flowing through the flow path 48 of the infrared heater 30. Furthermore, the controller 60 outputs a control signal for adjusting the magnitude of the power supplied from the power supply source 62 to the filament 32 to the power supply source 62 to individually control the filament temperature of the infrared heater 30. Further, the controller 60 can adjust the passage time of the coating film 52 in the drying main body 14 by controlling the rotation speed of the rolls 54 and 56.

  Although the sheet | seat 50 is not specifically limited, For example, it is a film-form thing excellent in intensity | strength, such as PET film. The thickness of the sheet 50 is not particularly limited, but is 10 to 100 μm. The coating film 52 is applied to the upper surface of the sheet 50, and is used as a thin film for MLCC (multilayer ceramic capacitor) after drying. The coating film 52 contains, for example, ceramic powder or metal powder, an organic binder, and an organic solvent.

  Next, how the coating film 52 is dried using the thus configured drying furnace 10 will be described. First, the controller 60 rotates the rolls 54 and 56 to start conveying the sheet 50. Then, the sheet 50 is unwound from the roll 54 disposed at the left end of the drying furnace 10. Also, the coating film 52 is applied to the upper surface of the sheet 50 by a coater (not shown) immediately before being fed into the carry-in path 19 from the carry-in port 19a. Then, the sheet 50 is carried into the carry-in path 19, passes under the partition structure 70 in the carry-in path 19, and is carried into the drying main body 14 from the opening 17. Further, the controller 60 controls the internal wind supply device 20, the internal wind intake device 25, the infrared heater 30, the exhaust device 81, and the inflow air supply device 90. Thereby, while the sheet 50 passes through the drying main body portion 14, the coating film 52 formed on the upper surface of the sheet 50 is dried by being irradiated with infrared rays from the infrared heater 30. At the same time, the cooling is performed by the internal wind from the internal wind supply device 20 or the inflow air from the inflow air supply device 90. The controller 60 controls the flow rate of the internal wind and the inflow air so that the temperature of the seat 50 becomes a predetermined value (for example, 60 °, 50 °, 45 °, etc.) or less. This flow rate may be determined in advance. Alternatively, for example, the flow rate may be adjusted so that the temperature of the sheet 50 is kept below a predetermined value based on the temperature detected by a temperature sensor provided on the sheet 50 or in the drying main body 14. In this way, the coating film 52 is dried to form a thin film while the sheet 50 is kept at a predetermined value or less, and is transported from the opening 18. The unloaded thin film (coating film 52) is taken up together with the sheet 50 on a roll 56 installed at the right end of the drying main body 14. Thereafter, the thin film is peeled off from the sheet 50, cut into a predetermined shape and laminated, and an MLCC is manufactured.

  Here, the flow of the atmospheric gas and the flow of the inflow air in the drying main body 14 during drying will be described. In FIG. 1, the flow of the atmospheric gas in the drying main body 14 including the internal wind is indicated by solid arrows, and the flow of the inflow air is indicated by white arrows. The internal wind supplied from the air supply nozzle 23 of the internal wind supply device 20 flows along the upper surface of the sheet 50 from the carry-out side of the sheet 50 toward the carry-in side, as indicated by the solid arrows in FIG. Then, the upper surface of the sheet 50 is cooled. The internal wind and the flow of atmospheric gas accompanying it are basically sucked by the exhaust nozzle 28 and exhausted through the exhaust fan 26. However, part of the atmospheric gas in the drying main body 14 may reach the carry-in path 19 from the opening 17 and flow out toward the carry-out port 19a. However, in the present embodiment, the inflow air from the air supply fan 91 is inclined from the opening below the fourth partition space 79 in the conveyance path 19 toward the lower right direction in FIG. Flows toward the top. Then, the air flows along the upper surface of the seat 50 to below the inside air outflow prevention portion 80 (between the inside air outflow prevention portion 80 and the seat 50). Here, the inflow air is normal temperature, and is lower than the atmospheric gas in the opening 17 affected by the temperature of the coating film 52. Therefore, the inflow air enters under the atmospheric gas from the drying main body 14 below the inside air outflow prevention unit 80. As a result, the inflow air pushes up the atmospheric gas to the internal air outflow prevention unit 80 so as to peel off the atmospheric gas from the upper surface of the sheet 50. Thereby, the atmospheric gas from the drying main body 14 flows not into the carry-in port 19a but into the first to third partition spaces 76 to 78 of the inside air outflow prevention unit 80. Moreover, since the first to third partition spaces 76 to 78 of the inside air outflow prevention unit 80 are inclined in a direction in which the upper part is away from the drying main body unit, the direction in which the atmospheric gas flows after being pushed up by the inflow air ( The upper left direction in FIG. 1 and the inclinations of the first to third partitioned spaces 76 to 78 coincide with each other. Therefore, it is easy to guide the atmospheric gas into the inside air outflow prevention unit 80. Then, the atmospheric gas in the inside air outflow prevention unit 80 is quickly exhausted by the exhaust fan 82. As described above, in the drying furnace 10 of the present embodiment, the atmospheric gas in the drying main body portion 14 is prevented from flowing out from the carry-out port 19a by the inside air outflow prevention portion 80 and the inflow air.

  According to the drying furnace 10 of the present embodiment described above, the inside air outflow prevention unit 80 is provided in the carry-in path 19 through which the sheet 50 is carried into the opening 17 of the drying main body unit 14 from the outside. The inside air outflow prevention portion 80 is located above the seat 50 and has first to third partition spaces 76 to 78 as inclined spaces inclined in a direction in which the upper portion is away from the drying main body portion 14. Then, a fluid having a temperature lower than the atmospheric gas in the opening 17 is supplied to the carry-in path 19 as an inflow air. The inflow air is supplied so as to flow in the carry-in path 19 in the direction of flowing into the drying furnace main body 14 and to flow below the inside air outflow prevention unit 80 along the upper surface of the sheet 50. By doing so, it is possible to further suppress the atmospheric gas flowing out from the opening 17 along the upper surface of the sheet 50 to the carry-in path 19 from flowing out. In addition, the organic solvent is contained in the coating film 52, and the organic solvent volatilized by drying is also contained in the atmospheric gas in the dry main body part. Therefore, it is highly significant to suppress the atmospheric gas containing such an organic solvent from flowing out of the drying furnace 10.

  The inflow air supply device 90 supplies the inflow air so as to pass below the inside air outflow prevention unit 80. Therefore, the force by which the inflow air strips off the atmospheric gas and pushes it up toward the inside air outflow prevention unit 80 becomes stronger.

  Furthermore, an infrared heater 30 provided in the drying main body portion 14 is provided, and the inflow air supply device 90 passes under the inside air outflow prevention portion 80 and reaches the inside of the drying main body portion 14 from the opening 17. To cool the upper surface of the sheet 50. Therefore, while the coating film 52 is dried by infrared rays from the infrared heater 30, the coating film 52 and the sheet 50 can be cooled with the inflow air to suppress the increase in temperature. Thereby, the thermal expansion at the time of drying of the sheet | seat 50 and subsequent shrinkage | contraction can be suppressed, and it can suppress that the coating film 52 deform | transforms with stress. Further, the inflow air can serve both as a role of further suppressing the outflow of the atmospheric gas to the outside and a role of cooling the coating film 52.

  Furthermore, the internal air supply device 20 supplies internal air along the upper surface of the sheet 50 from the carry-out side of the sheet 50 to the carry-in side of the drying main body 14 to cool the upper surface of the sheet 50. The inflow air supply device 90 supplies the inflow air into the drying main body 14 in the direction opposite to the internal air. By carrying out like this, the coating film 52 and the sheet | seat 50 can be cooled also by internal wind, and the deformation | transformation of the coating film 52 can be suppressed. And since inflow air is supplied in the direction opposite to internal wind, compared with the case where direction is the same, the outflow of atmospheric gas to the exterior by internal wind can be suppressed more, for example. Further, since the internal wind is supplied in the direction opposite to the conveyance direction of the sheet 50, the relative speed of the internal wind with respect to the sheet 50 is increased, and the cooling effect on the upper surface of the sheet 50 is enhanced. When the internal wind is supplied from the carry-out side, when the internal wind reaches the carry-in side, the temperature of the internal wind rises and the cooling effect tends to be low. However, since the inflow air is supplied from the side opposite to the internal air in the drying main body 14, such a portion having a low cooling effect can be efficiently cooled by the inflow air. In this way, by supplying the internal air and the inflow air in opposite directions, it is possible to suppress a part of the sheet 50 in the drying main body 14 from becoming high temperature, and it is easy to keep the temperature of the sheet 50 low.

  Further, the inflow air supply device 90 flows in the carry-in path 19 so as to be inclined toward the upper surface of the sheet 50 with respect to the conveyance direction of the sheet 50, and then, along the upper surface of the sheet 50, the inside air outflow prevention unit 80. Inflow air is supplied to flow downward. Therefore, the inflow air has a flow from the top to the bottom on the side of the carry-out outlet 19a with respect to the inside air outflow prevention portion 80 in the carry-in path 19. Thereby, the conveyance path 19 can be blocked by the inflow air, and the outflow of the atmospheric gas to the outside can be further suppressed.

  Moreover, the drying furnace 10 includes a partition structure 70 having first to fourth partition spaces 76 to 79 that are inclined in a direction in which the upper part is away from the drying main body 14 along the transport direction of the sheet 50. . In the partition structure 70, one or more of the plurality of partition spaces on the side of the drying main body 14 is an inclined space of the inside air outflow prevention unit 80, and one or more of the plurality of partition spaces on the side opposite to the drying main body 14. Is an inclined path of the inflow air supply device 90. Accordingly, the inclined space of the inside air outflow prevention unit 80 and the inflow air supply device 90 inclined path can be combined into one partition structure 70. Therefore, the drying furnace 10 provided with the inside air outflow prevention unit 80 and the inflow air supply device 90 can be manufactured more easily.

  It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that the present invention can be implemented in various modes as long as it belongs to the technical scope of the present invention.

  For example, in the above-described embodiment, the first to third partition spaces 76 to 78 are the inclined spaces of the inside air outflow prevention unit 80, and the fourth partition space 79 is the inclined path of the inflow air supply device 90. The structure 70 is collected, but is not limited thereto. For example, the first to second partition spaces 76 to 77 may be the inclined space of the inside air outflow prevention unit 80, and the third to fourth partition spaces 78 to 79 may be the inlet air supply device 90 inclined path. Further, the inclined space of the inside air outflow prevention unit 80 and the inclined path of the inflow air supply device 90 may be provided separately.

  In the embodiment described above, the inflow air supply device 90 has the fourth partition space 79 as the inclined path, but is not limited thereto. For example, the inflow air supply device 90 flows horizontally along the upper surface of the sheet 50 from the carry-in port 19 a, which is the end of the carry-in path 19 opposite to the drying main body 14, and flows into the drying main body 14. It is good also as what supplies a wind. FIG. 4 is a longitudinal sectional view of a drying furnace 110 according to a modification in this case. In FIG. 4, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in the figure, in the drying furnace 110, the partition structure 70 has only the first to third partition spaces 76 to 78, and the partition structure 70 serves as the inside air outflow prevention unit 80 as it is. The inflow air supply device 90 includes an air supply fan 91, a pipe structure 92, and an air supply nozzle 193. The air supply nozzle 193 supplies the inflow air from the air supply fan 91 into the carry-in path 19 via the pipe structure 92. The air supply nozzle 193 is provided at an end of the carry-in path 19 on the carry-in port 19 a side, and opens horizontally from the carry-in port 19 a toward the opening 17. In the drying furnace 110, the inflow air supplied from the air supply nozzle 193 flows horizontally along the upper surface of the sheet 50 from the carry-in port 19 a side and flows toward the drying main body 14. Even if the inflow air is supplied in this manner, the atmosphere gas is pushed up into the inside air outflow prevention unit 80 so that the inflow air enters the lower side of the atmosphere gas from the drying main body portion 14 as in the present embodiment. Therefore, the outflow of the atmospheric gas from the drying main body 14 can be further suppressed. Note that the air supply nozzle 193 may be provided outside the carry-in path 19 and the inflow air may be supplied from the outside into the carry-in entrance 19a so as to flow horizontally along the upper surface of the sheet 50.

  In the embodiment described above, the inflow air passes under the inside air outflow prevention unit 80 and reaches the drying main body 14 from the opening 17, and cools the upper surface of the sheet 50 in the drying main body 14. Not limited to this. For example, the inflow air may not cool the upper surface of the sheet 50. The inflow air may pass under the inside air outflow prevention unit 80 but may not reach the inside of the drying main body unit 14. Alternatively, the inflow air may not pass below the inside air outflow prevention unit 80 and reach only below the inside air outflow prevention unit 80. Even in such a case, the outflow of the atmospheric gas from the drying main body 14 can be suppressed by the inflow air.

  In the above-described embodiment, the carry-in path 19, the partition structure 70, the inside air outflow prevention unit 80, the exhaust device 81, and the inflow air supply device 90 are provided on the opening 17 side. It may be provided. FIG. 5 is a longitudinal sectional view of a drying furnace 210 according to a modification in this case. In FIG. 5, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted. As shown in FIG. 5, the drying furnace 210 is provided with a carry-out path 219 having the same configuration as the carry-in path 19 on the opening 18 side, and the sheet 50 carried out from the carry-out outlet 219 a at the right end of the carry-out path 219 is rolled 56. It is designed to be wound up by In addition, a partition structure 270, an inside air outflow prevention unit 280, an exhaust device 281, and an inflow air supply device 290 are provided above the carry-in path 219. These have the same configuration except that they are formed symmetrically with the carry-out path 19, the partition structure 70, the inside air outflow prevention unit 80, the exhaust device 81, and the inflow air supply device 90, respectively, in FIG. . In the drying furnace 210, inflow air having a temperature lower than that of the atmospheric gas in the opening 18 is supplied from the inflow air supply device 290. For this reason, when there is an atmospheric gas flowing out from the opening 18 along the upper surface of the sheet 50 to the carry-out path 219, the inflow air from the inflow air supply device 290 is below the inside air outflow prevention unit 280 and below the atmospheric gas. Dive in. As a result, the inflow air pushes up the atmospheric gas to the inside air outflow prevention unit 290 so as to peel off the atmospheric gas from the upper surface of the sheet 50. Thereby, it is possible to further suppress the atmospheric gas from flowing out from the carry-out port 219a through the carry-out path 219. In the drying furnace 210, the carry-in path 19, the partition structure 70, the inside air outflow prevention unit 80, the exhaust device 81, and the inflow air supply device 90 may be omitted. Even in this case, it is possible to suppress the atmospheric gas from flowing out from the carry-out port 219a. However, since it is possible to suppress the outflow of the atmospheric gas by supplying the inflow air in the direction opposite to the direction of the internal air from the internal air supply device 20, it is preferable not to omit it. The carry-in path 219, the compartment structure 270, the inside air outflow prevention unit 280, the exhaust device 281 and the inflow air supply device 290 are respectively the carry-in path 19, the compartment structure 70, the inside air outflow prevention unit 80, the exhaust device 81, and the inflow air. It may not be formed symmetrically with the supply device 90.

  In the above-described embodiment, the internal wind from the internal wind supply device 20 is opposite to the conveyance direction of the sheet 50, but may be the same direction. In this case, since the inflow air in the direction opposite to the direction of the internal air from the internal air supply device 20 can be supplied to suppress the outflow of the atmospheric gas, the carry-in path 219, the partition structure 270, and the like shown in FIG. It is preferable to include an inside air outflow prevention unit 280, an exhaust device 281 and an inflow air supply device 290.

  In the above-described embodiment, the internal wind intake device 25 exhausts the atmospheric gas in the drying main body 14, but the internal wind intake device 25 may be omitted. Even in this case, the exhaust device 81 can exhaust the atmospheric gas in the dry main body 14 without flowing out.

  In the above-described embodiment, devices similar to the internal wind supply device 20 and the internal wind intake device 25 may be provided on the lower surface side of the sheet 50 in the drying main body 14. If it carries out like this, the sheet | seat 50 can be cooled also with the internal wind from this apparatus.

  In the above-described embodiment, an inflow air supply port may be provided on the lower surface side of the sheet 50 in the carry-in path 19 to supply inflow air flowing in the direction from the carry-in port 19 a toward the drying main body 14.

  In the embodiment described above, the number and arrangement of the infrared heaters 30 may be different from those in FIG. Further, the infrared heater 30 may be provided on the lower surface side of the sheet 50 in the drying main body 14. Alternatively, the infrared heater 30 may not be provided, and the coating film 52 may be dried by the internal wind from the internal wind supply device 20. In that case, the internal air may be hot air (for example, 60 to 150 ° C.) instead of cold air.

  In the embodiment described above, several support rollers for supporting the sheet 50 from below may be provided in the carry-in path 19 or the drying main body 14. In this way, it is possible to prevent the sheet 50 from being bent by gravity.

  In the above-described embodiment, the internal wind intake device 25 includes the exhaust fan 26 and the exhaust device 81 includes the exhaust fan 82. However, the present invention is not limited to this. For example, only one of the exhaust fan 26 and the exhaust fan 82 may be provided, and both the pipe structure 27 and the pipe structure 83 may be connected to the exhaust fan. Even in this case, the atmospheric gas in the drying main body 14 and the inside air outflow prevention unit 80 can be discharged.

  In the above-described embodiment, the outer periphery of the filament 32 is concentrically covered by the plurality of tubes 36 and 40 that function as an infrared ray absorbing filter having a wavelength exceeding 3.5 μm as the infrared heater 30. , 40 in which a cooling fluid channel 48 that suppresses an increase in the surface temperature of the infrared heater 30 is used, but other infrared heaters may be used.

  In the embodiment described above, air is used as the atmospheric gas of each drying furnace 10, but an inert gas such as nitrogen may be used instead of air.

  In the above-described embodiment, the coating film 52 includes ceramic powder or metal powder, an organic binder, and an organic solvent, but is not limited thereto. For example, water may be used instead of the organic solvent. In this case, the atmospheric gas in the drying main body portion 14 contains moisture evaporated by drying. Therefore, it is highly significant to suppress such atmospheric gas containing water from flowing out of the drying furnace 10. In addition to the organic solvent and water, it is often not preferable that the gas generated from the coating film 52 by drying flows out of the drying furnace 10 as it is. Therefore, it is meaningful to suppress the outflow of the atmospheric gas to the outside of the furnace regardless of the components of the coating film 52.

  In the embodiment described above, the coating film 52 is used as a thin film for MLCC, but is not limited thereto. For example, it may be used as a thin film for LTCC (low temperature fired ceramics) or other green sheets. Moreover, although the coating film 52 shall be apply | coated on the sheet | seat 50 with a coater, you may form a film | membrane on the upper surface of the sheet | seat 50 by another method.

  The present invention relates to an industry in which a sheet having a film formed thereon is required to be dried, for example, a film containing ceramic powder or metal powder, an organic binder, and an organic solvent or water on the upper surface of a sheet made of PET film. And this film is dried and laminated to be used in the industry for manufacturing MLCC.

10, 110, 210 Drying furnace, 14 Drying main body, 15 Front end surface, 16 Rear end surface, 17, 18 Opening, 19 Carry-in path, 19a Carry-in port, 20 Internal air supply device, 21 Air supply fan, 22 Pipe structure, 23 Air supply nozzle, 25 Internal air intake device, 26 Exhaust fan, 27 Pipe structure, 28 Exhaust nozzle, 30 Infrared heater, 32 Filament, 34 Electrical wiring, 36 Inner pipe, 37 Temperature sensor, 38 Heater body, 40 Outer pipe , 42 cap, 44 wiring outlet, 46 fluid inlet / outlet, 48 flow path, 49 holder, 50 sheet, 52 coating film, 54, 56 roll, 60 controller, 62 power supply source, 64 cooling fluid supply source, 66 on-off valve, 68 Flow control valve, 70, 270 Compartment structure, 72 Outer wall, 74 Inner wall, 76-79 First to fourth Image space, 80,280 Inside air outflow prevention unit, 81,281 Exhaust device, 82 Exhaust fan, 83 Pipe structure, 90,290 Inflow air supply device, 91 Supply air fan, 92 Pipe structure, 193 Supply air nozzle, 219 Unloading path, 219a Unloading exit.

Claims (7)

A drying furnace that continuously transports a sheet on which a film to be dried is formed on the upper surface and performs drying,
A drying body for drying the membrane;
A conveyance path for carrying the sheet from the outside into the opening of the drying main body or carrying it out from the opening;
An inside air outflow prevention unit provided with an opening in the conveyance path, located above the sheet, and having an inclined space inclined in a direction in which an upper part is away from the drying main body unit;
Inflow air supply means for supplying a fluid having a temperature lower than the atmospheric gas in the opening to the transport path as inflow air;
With
The inflow air supply means supplies the inflow air so as to flow through the conveyance path in a direction of flowing into the drying furnace main body, and to flow under the inside air outflow prevention unit along the upper surface of the sheet.
drying furnace. The inflow air supply means supplies the inflow air so as to pass below the inside air outflow prevention unit;
The drying furnace according to claim 1. A drying furnace according to claim 2,
An infrared heater provided in the drying body,
With
The inflow air supply means cools the upper surface of the sheet by supplying the inflow air so as to pass under the inside air outflow prevention portion and reach the drying main body portion from the opening.
drying furnace. A drying furnace according to claim 3,
An internal air supply means for supplying an internal air along the upper surface of the sheet and cooling the upper surface of the sheet from one side of the carrying-in side or the carrying-out side of the sheet to the other side in the drying main body,
With
The inflow air supply means supplies the inflow air into the drying main body in a direction opposite to the internal air;
drying furnace. The internal wind supply means supplies the internal wind from the carry-out side of the sheet toward the carry-in side,
The inside air outflow prevention part is provided in a carry-in path for carrying the sheet from the outside into the drying main body part,
The inflow air supply means flows in the carry-in path in a direction to flow into the drying furnace main body, and passes under the inside air outflow prevention portion along the upper surface of the sheet to reach the drying main body. Supplying the inflow air to
The drying furnace according to claim 4. The inflow air supply means flows in the conveyance path so as to incline with respect to the conveyance direction of the sheet toward the upper surface of the sheet, and then flows below the inside air outflow prevention unit along the upper surface of the sheet. So as to supply the inflow air,
The drying furnace according to any one of claims 1 to 5. A drying furnace according to claim 6,
A partition structure having a plurality of partition spaces inclined in a direction in which the upper part is away from the drying main body along the sheet conveyance direction;
With
The inflow air supply means has an inclined path that is inclined in a direction in which the upper part is away from the drying main body, and the inflow air passes through the inclination path in the conveyance direction of the sheet. Inclining to generate a flow toward the upper surface of the sheet,
In the partitioned structure, at least one of the plurality of partitioned spaces on the side of the drying main body becomes the inclined space of the inside air outflow prevention unit, and one or more of the plurality of partitioned spaces on the side opposite to the drying body portion. Is the inclined path of the inflow air supply means,
drying furnace.