JP2019052835A - Dry room for gas replacement - Google Patents

Abstract

To provide an inert gas purifier capable of performing maintenance and setup changing of a manufacturing apparatus in relatively short time in a low dew point environment, in a dry container of a low inert gas concentration in which the manufacturing apparatus is accommodated.SOLUTION: In a dehumidifying purifier for gas replacement of a container necessary for keeping an inner part clean at a low dew point and a low active gas concentration, the container is accommodated into a low dew point dry room, while maintenance, preventive maintenance or the like is performed, dry air is entered into the container in one pass such that humidity is discharged outside an apparatus, the whole nitrogen circulation line is closed with a valve and like, the inside of a pipe is filled with nitrogen as it is, dry air by virtue of a dehumidifier is circulated through a circulation path, thereby, a humidity load of a container external part can be suppressed to the minimum and pause time by virtue of air brake can be sharply shortened. Further, the dehumidifier and an oxygen removal device are divided, thereby, the number of circulation times of respective one is changed and, thereby, an optimum operational environment can be adjusted.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a drying chamber having a low active gas concentration (hereinafter referred to as “low active gas concentration”) where the active gas concentration is as close to 0 ppm as possible, such as a booth where an organic EL display manufacturing apparatus is installed, A dehumidifier and gas that can perform maintenance and adjustment of manufacturing equipment in a relatively short time in an environment of a low dew point (hereinafter, a dew point temperature of 0 ° C. or less is referred to as a “low dew point”). The present invention relates to a gas replacement system including a refiner.

  Conventionally, organic EL elements used in organic EL display devices expected as next-generation flat panel displays to replace liquid crystal display devices are promising for use as solid light-emitting, inexpensive large-area full-color display elements and writing light source arrays. Active research and development is underway. However, organic substances such as organic light emitting materials used for organic EL elements, electrodes, and the like are weak against moisture, and performance and characteristics are rapidly deteriorated by moisture in the air. Therefore, even in the experiments accompanying these developments, it is necessary to perform production and experiments in a booth purged with an inert gas such as air having a very low dew point or nitrogen obtained by vaporizing liquid nitrogen.

  Currently, organic EL displays (OLEDs) are manufactured using a printing technology such as inkjet technology to make liquid organic EL materials a uniform thin film on the substrate, creating elements with improved production efficiency and performance. Technology is being developed. In order to develop such a manufacturing technique, it is necessary to make the environment of the manufacturing apparatus have a low active gas concentration at a low humidity such as a humidity of 1 ppm or less and oxygen of 1 ppm or less. However, when performing maintenance or adjustment of the manufacturing apparatus in the booth, it is necessary to return the low-humidity nitrogen environment to the atmospheric environment (hereinafter referred to as “atmospheric break”).

  At this time, when the nitrogen environment is replaced with normal air, various components of the apparatus inside adsorb moisture, and when returning to the nitrogen environment, it takes a very long time for the components to desorb the adsorbed moisture.

  Patent Document 1 discloses a technique for minimizing the internal volume of the gas enclosure assembly in order to minimize the amount of inert gas for returning the air environment from the atmospheric environment to the nitrogen environment again and to minimize the downtime. There is something.

Special table 2015-510254 gazette

  As disclosed in Patent Document 1, the gas enclosure is framed and the internal volume is made as small as possible, thereby minimizing the amount of inert gas in the gas enclosure and minimizing downtime due to maintenance, etc. Although the work space can be optimized to adapt to the installation area of various OLED manufacturing equipment, the gas purification system for simultaneously performing inert gas purification and moisture removal accompanying the suspension is also stopped. Therefore, there is a problem that it takes too much time to make the inside of the booth low humidity and low outgas concentration environment again. In addition, since the gas purification device and the dehumidification device are in the same mechanism, the purification rate is different between oxygen and moisture, and it takes time to remove moisture compared to the removal of oxygen. .

  In order to solve the above problems, the present invention provides an airtight container in a drying chamber, and supplies a low active gas and a low dew point gas to the airtight container. Since each can be controlled independently, if a person enters the hermetic container due to adjustment, etc., if the supply of low active gas is stopped while maintaining the supply of low dew point air, it will be suspended due to an atmospheric break. Time can be greatly reduced. That is, water molecules are polar substances, and when air is introduced into an airtight container that needs to be maintained at a low dew point, the water molecules adhere to the wall surface of the airtight container and the inside of the filter. In order to discharge the adhering water molecules, it is necessary to supply low dew point air for a long time. In the present invention, the supply of the low dew point gas can be maintained with the supply of the low active gas stopped. The dew point in the hermetic container can reach a low state quickly even after an atmospheric break. Moreover, even if it is the nitrogen gas which entered the cylinder as a low active gas, or even the air from which oxygen was removed, the price of the gas is high, and it will be expensive unless the time for atmospheric break is shortened. On the other hand, if low dew point gas is produced with a desiccant rotor, there is no cost. Therefore, by maintaining the supply of the low dew point gas and stopping the supply of the low active gas, the total cost can be reduced.

  In addition, since the mechanism for removing moisture and oxygen is usually in the same device, the flow rate of the gas flowing through the moisture removal device and the oxygen removal device is the same. Since it can be freely changed, it has become possible to create a dry room with a low active gas concentration under optimal operating conditions that simultaneously achieve both low humidity and low active gas concentration.

  The gas replacement dry room of the present invention is configured as described above, and can be unidirectionally (hereinafter referred to as “one-pass”) without being circulated from an air purification filter such as a HEPA filter or ULPA filter installed in the upper part of the container even during an atmospheric break. By supplying low dew point air, the filter that most easily retains moisture does not retain moisture, and maintenance, maintenance, changeover, etc. are performed. In addition, an inert gas purifier and a desiccant dehumidifier are installed in series in the circulation path of the container, a circulation path separated from the circulation path is provided separately, and the circulation path provided separately during the atmospheric break is circulated. Air was kept away from the atmosphere. By doing so, the return time for returning from the atmospheric environment after the atmospheric break of the container to the environment of low humidity and low active gas concentration could be greatly shortened. Furthermore, by individually controlling the flow rate of the gas flowing through this dehumidifier and inert gas purifier, a dry room that can be easily optimized in an environment with low humidity and low active gas concentration in a short time. I was able to.

FIG. 1 is a flowchart in the first embodiment of the dry room of the present invention.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. In this embodiment, as a gas replacement dehumidifying apparatus and a gas replacement method for a container that needs to keep the inside clean with a low dew point and a low active gas concentration, an organic EL display (OLED) that uses a printing technique such as an inkjet technique is manufactured. Or the container of a research and development apparatus is demonstrated to an example. The present invention is not limited to organic EL display (OLED) manufacturing or R & D equipment, but also develops lithium ion battery materials and semiconductor fields that need to keep the storage space clean with a low dew point and low active gas concentration. It can also be used for a storage container such as a glove box or a closed space.

  Hereinafter, Example 1 of the dry room for gas replacement of the present invention will be described in detail with reference to FIG. 1 is an airtight container that needs to keep the interior clean with a low dew point and low active gas concentration. It contains a manufacturing device 2 used for the manufacture and research and development of organic EL displays (OLEDs). A path 4 and an air purification filter 3 such as a HEPA filter or a ULPA filter are provided. Note that the air purification filter 3 may be a plurality of fan filter units. Nitrogen gas and dry air from the dehumidifier 38 are supplied to the container 1 through the pipe A.

  The air to be treated in the container 1 passes through the pipe B and is sent to a nitrogen purifier 40 as an inert gas purification device, where oxygen, which is an active gas in the air to be treated, is removed. A catalyst container 5 for purifying nitrogen contains a copper catalyst, a platinum catalyst, and the like. When the catalyst breaks through, the temperature is raised by the heater 6 while flowing nitrogen gas and hydrogen gas, and the catalyst is regenerated. Reference numeral 7 denotes a pump for sending the air to be treated to the nitrogen purifier 40, and the purified air to be treated is sent to the desiccant dehumidifier 39 as a low dew point gas supply device by the blower 9 through the cooler 8. In this embodiment, a catalyst such as a copper catalyst or a platinum catalyst is used. However, the present invention is not limited to these, and other catalysts containing copper and / or platinum as main components may be used.

  A honeycomb rotor 11 for the desiccant dehumidifier 39 is divided into a processing zone 12, a purge zone 13, and a regeneration zone 14. Reference numeral 17 denotes a rotor drive motor such as a geared motor for rotationally driving the honeycomb rotor. Air to be treated is supplied to the treatment zone 12 by the blower 9 through the precooler 10. Part of the air to be treated is branched in front of the treatment zone 12, passes through the purge zone 13, and then is sent to the regeneration zone 14 through the regeneration heater 36. The air leaving the regeneration zone 14 is cooled by the cooler 15, and water condensed from moisture in the regeneration air desorbed from the honeycomb rotor is removed as a drain and returned to the front of the blower 9. The air to be treated that has exited the desiccant dehumidifier 39 is warmed by the after heater 16 as necessary, and returned to the container 1 through the pipe D. If the nitrogen gas supply facility has sufficient capacity, install the desiccant dehumidifier 39 in an airtight room and supply nitrogen gas to the room to prevent the active gas from entering the desiccant dehumidifier 39. It is good also as a structure which suppresses.

  Reference numeral 34 denotes an airtight drying chamber that accommodates the container 1, which is sized to be entered by a person for adjustment or the like. Dry air from the dry air supply device 37 is supplied from the pipe G, and the drying chamber is supplied from the pipe H. 34 air is returned to the dry air supply device 37. The pipe E is an exhaust path for exhausting the air in the container 1 to the outside of the drying chamber 34. In the present embodiment, the honeycomb rotor 11 having the purge zone 13 is used. However, the present invention is not limited to this, and a configuration using a honeycomb rotor that is divided into a treatment zone and a regeneration zone may be used.

  The operation of the dry room for gas replacement of the present invention having the above configuration will be described first with respect to nitrogen replacement and circulation operation of the container 1. The valves 18, 19, 21, 22, 23, 24, 25, 27, 28, 29, 30, 31, 33, and 35 are opened, and nitrogen gas and dry air are sent from the pipe A to the container 1. When the oxygen concentration in the container 1 is reduced to 100 ppm or less, the valves 30, 33, and 35 are closed to supply dry air having a low dew point from the nitrogen purifier 40, the desiccant dehumidifier 39 and the pipe G to the drying chamber 34. The operation of the dry air supply device 37 that circulates the dry air is started. In addition, by adjusting the valves 24 and 25 as necessary, the amount of air that circulates from the container 1 through the pipe B to the nitrogen purifier 40 and the amount of air that goes directly to the desiccant dehumidifier 39 are adjusted. For example, the circulation is continued until a specified concentration such as an oxygen concentration of 1 ppm or less and a moisture concentration of 1 ppm or less is reached, and thereafter, the operation of the production apparatus 2 is started, and tests for manufacturing and R & D of OLED are started.

  In the first embodiment, the supply of nitrogen to the container 1 is performed from the pipe A. However, the present invention is not limited to this, and the nitrogen may be supplied from the inlet of the nitrogen purifier 40. And the desiccant dehumidifier 39 may be supplied.

  Next, an atmospheric break for performing maintenance, setup change, adjustment, etc. of the container 1 will be described. The valves 18, 19, 21, 23, and 31 are closed, and the valves 30, 32, and 33 are opened to isolate the container 1 and the nitrogen circulation line from the pipe B to the pipe D. The airtightness of the container 1 is opened, and dry air is introduced from the upper part of the container 1 through the pipe A, whereby nitrogen is replaced with air. In addition, the valve 32 of the pipe F is also opened so that the low dew point dry air supplied from the dry air supply device 37 via the pipe G is supplied from the upper part of the container 1 in one pass. Since air can be supplied safely at a time, the replacement speed of nitrogen and air can be greatly reduced. By supplying dry air in one pass without circulating the inside of the container 1 from the top of the air purification filter 3 that is most likely to retain moisture in the container 1, the moisture remains in the container even if a person works inside. It is discharged outside without remaining in 1. Note that the pipe F and the pipe G may be connected so that the entire amount of dry air with a low dew point supplied to the drying chamber 34 by a valve operation or the like is supplied directly from the upper part of the container 1.

  In the nitrogen circulation line, when the valve 30 is opened, air passes through the pipe C as a circulation path, so that dry air having a high nitrogen concentration and low humidity circulates. When the catalyst in the catalyst container 5 of the nitrogen purifier 40 is regenerated, the valve 35 is opened to bypass the nitrogen purifier 40 and send air to the desiccant dehumidifier 39 for circulation. In this way, by operating the valve by dividing the dehumidifying device and the oxygen removing device, the optimum operating environment can be prepared by changing the flow rate and the number of circulations of the gas flowing through each device. In addition, about a valve | bulb, it is not limited to this, You may use an air volume adjusting device, such as a damper and VAV (Variable Air Volume).

  In this Example 1, one nitrogen purifier 40 was used. However, while two or more nitrogen purifiers were installed in parallel and the catalyst of one nitrogen purifier was being regenerated, It is good also as a structure which performs a nitrogen purification process in a nitrogen refiner.

  Further, a mechanism having a nitrogen refining function may be mounted inside the desiccant dehumidifier 39 so that the nitrogen purifier 40 is eliminated as an integrated device. In this case, by providing a circulation path, a bypass path, etc., it is possible to individually adjust the humidity and inert gas concentration in the container 1 so that an environment with a low active gas concentration and a low dew point can be created. To. By doing in this way, it becomes possible to set it as a space-saving gas substitution system rather than Example 1, and it becomes possible to suppress initial cost concerning piping, installation work, etc.

  In this way, the inside of the airtight container 1 that needs to be kept clean with a low dew point and a low active gas concentration is covered with a drying chamber 34 that supplies dry air with a low dew point, thereby minimizing moisture intrusion from the outside. It becomes possible to suppress. Further, unlike the prior art in which oxygen removal and moisture removal are performed by a single gas purification system as in Patent Document 1, oxygen removal is performed by the nitrogen purifier 40, and moisture removal is separately performed by the desiccant dehumidifier 39. As a result, the oxygen removal performance and moisture removal performance can be arbitrarily adjusted, which facilitates device optimization and device management.

  As described above, the return time from the atmospheric environment after the atmospheric break of the container 1 to returning to the clean environment with a low dew point and low active gas concentration can be shortened to 1/5 to 1/10 of the prior art. did it. In addition, a gas replacement system that can easily optimize the inside of the container 1 at a low humidity and a low active gas concentration can be realized.

  The present invention can also be used for a storage container such as a glove box used for developing a lithium ion battery material or the like that needs to keep the storage space clean with a low dew point and a low active gas concentration.

DESCRIPTION OF SYMBOLS 1 Container 2 Manufacturing apparatus 3 Air purification filter 4 Gas circulation path 5 Catalyst container 6 Heater 7 Pump 8 Cooler 9 Blower 10 Precooler 11 Honeycomb rotor 12 Processing zone 13 Purge zone 14 Regeneration zone 15 Cooler 16 After heater 17 Rotor drive motor 18 19, 21, 22, 23, 24, 25, 27, 28, 29, 30, 31, 32, 33, 35 Valve 20, 26 Flow meter 34 Drying chamber 36 Regenerative heater 37 Dry air supply device 38 Dehumidifier 39 Desiccant Dehumidifier 40 Nitrogen purification machine

Claims (5)

  An airtight container housed in a drying chamber in which dry air from a dry air supply device is circulated is provided, and a low dew point gas supply device and an inert gas purification device are connected to the airtight container, A gas exhaust passage for supplying the low dew point gas through a filter for removing foreign substances in the low dew point gas, connected to the airtight container and exhausting the gas in the container to the outside of the drying chamber, and the drying chamber A pipe for recirculating the internal gas to the dry air supply device, and the low dew point gas supply device and the inert gas purification device independently adjust the moisture removal performance and oxygen removal performance. A dry room characterized by being able to do so.   2. The dry room according to claim 1, further comprising an air volume adjusting device for isolating the airtight container and the nitrogen circulation line, and providing a circulation path so that air circulates through the isolated nitrogen circulation line. .   The dry room according to claim 1 or 2, wherein the foreign matter removing filter is a fan filter incorporating a HEPA filter and / or a ULPA filter.   The dry room according to any one of claims 1 to 3, wherein the inert gas purifier is a nitrogen purifier containing a catalyst mainly composed of copper and / or platinum.   The dry room according to claim 1, wherein the low dew point gas supply device is a desiccant dehumidifier.

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