KR20100069542A - Substrate firing furnace of the circle method - Google Patents

Abstract

PURPOSE: A circulation type substrate furnace is provided to obtain a stable sintering temperature by controlling the sintering temperature inside of a furnace body main body part using a main heater. CONSTITUTION: A furnace body main body part(10) accepts a substrate to the inside. A circulation route(20) supplies a hot air exhausted from the furnace body main body part to the furnace body main body part by circulating. A circulation fan(40) circulates the hot air. A main heater(52) heats the hot air with circulating the circulation route. A catalyst filter part(70) is installed on the circulation route. The catalyst filter part includes a main filter(54) capable of supporting the catalyst.

Description

SUBSTRATE FIRING FURNACE OF THE CIRCLE METHOD}

The present invention is a substrate for thin electronic components such as a glass substrate for a liquid crystal display device, a glass substrate for a plasma display panel (PDP) or a semiconductor wafer while circulating hot air (hereinafter, simply referred to as a “substrate”). And a circulation type substrate firing furnace for firing.

One of the manufacturing processes of the color filter includes a step of firing a glass substrate on which color ink has been impregnated with inkjet. This firing step proceeds by holding the glass substrate for a predetermined time in an atmosphere of atmosphere in a firing furnace heated to a predetermined firing temperature. In the case of forming the metal wiring on the glass substrate, the glass substrate is fired in an inert gas atmosphere such as nitrogen gas in the same firing furnace. In any firing step, many organic substances are generated and diffused in the atmosphere by volatilizing or oxidizing an organic solvent contained in an object to be baked such as a color ink on a glass substrate.

Therefore, during the firing process, the clean hot air is continuously blown to the firing furnace, and the exhaust gas is continuously performed to prevent organic matter from remaining in the firing furnace. Since a gas containing a large amount of organic matter exhausted from the kiln cannot be discharged to the outside as it is, a process of collecting organic matter in exhaust gas by a scrubber or the like has been performed.

However, when the heat exhaust from the kiln is treated with a scrubber, the amount of heat energy deprived is very high and the energy efficiency is poor. Therefore, a circulating kiln which uses as little heat energy as is exhausted by recycling the hot air once exhausted is also used. In the circulating kiln, a part of the heat exhaust of the kiln is exhausted to the outside, and a fresh amount of fresh air is introduced therein.

Even in a circulating firing furnace, a catalyst was installed in an exhaust line or a circulation line to decompose and remove organic matter. In order to sufficiently decompose organic matters, the catalyst temperature needs to be above a predetermined temperature. In particular, when the catalyst is installed in the exhaust line, the exhaust temperature decreases significantly, so a separate heater for heating the catalyst is an essential element. It was. Patent Literature 1 discloses a technique for providing a heater and a catalyst in an exhaust line, and detecting the outlet temperature of the catalyst to control the heater temperature.

[Patent Document 1] Japanese Patent Laid-Open No. 2005-338840

However, adding a heater only to heat the catalyst to the exhaust line for discharge to the outside becomes a large heat loss and a high cost factor. In addition, even in the case where a catalyst is provided in the circulation line, if additional heaters are similarly installed, there is a problem that not only the cost rises but also the controllability of the firing temperature becomes difficult. In other words, temperature control is required for each of the main heater and the catalyst auxiliary heater for circulation in the kiln, and since both of these heaters are installed in the circulation line, they become disturbing factors. The fluctuation of temperature becomes large. As a result, the stability of the firing temperature of the kiln was impaired, causing a problem in the reproducibility of the firing process.

The present invention has been made in view of the above problems, and an object thereof is to provide a circulating substrate baking furnace which has a low heat loss and a stable firing temperature.

SUMMARY OF THE INVENTION In order to solve the above problems, the invention of claim 1 is characterized in that, in a circulating substrate baking furnace for circulating hot air and firing a substrate, a furnace body part for accommodating a substrate therein and from the furnace body part A circulation path for circulating the discharged hot air and supplying it to the furnace body part again, a circulation fan installed in the circulation path for circulating hot air, a main heater for heating the hot air circulating in the circulation path, and the circulation path And a catalyst filter portion having a metal filter supporting the catalyst, and a trap means provided in the circulation path to trap carbon dioxide and / or water. do.

In the invention of claim 2, in the circulation type substrate baking furnace according to the invention of claim 1, the trap means is divided into two branches in the middle of the circulation path, and two flow paths are joined again. Two trap towers installed in parallel to each other, the switching means for selectively switching the two flow paths so that hot air passes through either one of the two trap towers, and controlling the timing of the switching of the switching means. It is characterized by including a switching control unit.

The invention of claim 3 is characterized in that the two trap towers are two adsorption towers for adsorbing carbon dioxide and / or water in the circulation type substrate baking furnace according to the invention of claim 2.

The invention of claim 4 is characterized in that the two trap towers are two absorption towers that absorb carbon dioxide in the circulation substrate baking furnace according to the invention of claim 2.

In addition, the invention of claim 5 is the circulation substrate baking furnace according to the invention of claim 4, wherein each of the two absorption towers is a discharge for discharging carbon dioxide absorbent and carbon dioxide absorbed from the absorber. And a recovery system for recovering carbon dioxide released from the absorber.

In addition, the invention of claim 6 is the circulation substrate baking furnace according to any one of claims 1 to 5, wherein the catalyst filter unit is located downstream of the furnace body in the circulation path to the trap means. It is characterized by being installed between.

In addition, the invention of claim 7 is the circulation type substrate firing furnace according to any one of claims 1 to 5, wherein the catalytic filter part extends to the furnace body part as a downstream side of the main heater in the circulation path. It is characterized by being installed between.

The invention of claim 8 is characterized in that the catalytic filter part is provided in each of the two flow paths in the circulation type substrate firing furnace according to any one of claims 2 to 5.

In addition, the invention of claim 9 is the circulation substrate firing furnace according to the invention of claim 1, wherein the catalyst includes a photocatalyst, and the catalyst filter unit is irradiated with light to irradiate the photocatalyst with light. A means is provided.

The invention of claim 10 is characterized in that a metal filter is provided in a hot air inlet of the furnace body part in the circulation type substrate baking furnace according to the invention of claim 1.

According to the present invention, since the hot air discharged from the furnace body part flows into the catalyst filter in the course of circulating the circulation path, the organic matter contained in the hot air is decomposed, so that a separate heater for heating the catalyst is unnecessary, resulting in heat loss. Can be reduced. In addition, since the firing temperature inside the furnace body portion can be adjusted by the control of only the main heater, temperature control becomes easy, and stable firing temperature can be obtained.

In particular, according to the invention of claim 2, in order to selectively switch the trap tower through which the hot air passes, the regeneration process of the other trap tower can be performed while the one trap tower is being used, so that maintenance is possible. It is possible to suppress a decrease in the operation rate of the substrate firing furnace.

In particular, according to the invention of claim 6, since the catalyst filter portion is provided in the circulation path from the furnace body portion to the trapping means downstream, the hot air discharged from the furnace body portion flows into the catalyst filter portion as it is. Thus, the organic matter contained in the hot air can be decomposed with high efficiency.

In particular, according to the invention of claim 7, since the catalyst filter portion is provided in the circulation path from the main heater to the furnace main body portion downstream, the hot air immediately after being heated by the main heater flows into the catalyst filter portion. Thus, the organic matter contained in the hot air can be decomposed with high efficiency.

In particular, according to the invention of claim 8, since the catalyst filter portions are provided in each of the two flow paths, the catalyst filter portion to be switched at the same time as the trap tower is switched is also switched to perform the regeneration treatment of the trap tower and the catalyst filter portion. Since maintenance can be performed, it is not necessary to stop the substrate baking furnace for maintenance of the catalyst filter unit, and the operation rate of the substrate baking furnace can be improved.

In particular, according to the invention of claim 9, since the catalyst supported on the metal filter includes a photocatalyst, organic matter remaining on the metal filter can be completely decomposed.

In particular, according to the invention of claim 10, since the main filter is provided at the hot air inlet of the furnace body part, organic matter remaining without being completely decomposed in the catalyst filter part is also removed, and the degree of cleanliness of the hot air introduced into the furnace body part is removed. Can be further improved.

BEST MODE FOR CARRYING OUT THE INVENTION [

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail, referring drawings. In addition, in this specification, a "trap" is a term of a concept including both "adsorption" which physically sucks in decomposition products, such as carbon dioxide, and "absorption" in which decomposition products are blown by a chemical reaction.

<1. First embodiment>

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the whole structure of 1st Embodiment of the circulation type substrate baking furnace which concerns on this invention. The substrate firing furnace performs a calcination process of a rectangular glass substrate W containing color ink for a color filter while circulating hot air, and a furnace body part for accommodating the calcination process by accommodating the glass substrate W. 10, a circulation path 20 for circulating hot air, a catalyst filter unit 70 having a catalyst for decomposing organic matters in a filter, an adsorption tower 30 for adsorbing moisture and carbon dioxide contained in the hot air, The circulation fan 40, the main heater 52 which heats hot air, and the metal filter 54 are provided. In addition, the control part 90 is provided in the board | substrate baking furnace.

The furnace body part 10 is a box body which can accommodate the glass substrate W in multiple stages (40 stages in this embodiment). The inside of the furnace main body portion 10 is a heat treatment space having a substantially rectangular pillar shape. On the inner wall surface of the furnace body 10, many forks are omitted. Each fork is extended along the horizontal direction from the inner wall surface of the furnace main body part 10 toward the heat treatment space. A plurality of forks are arranged side by side along the horizontal direction, and a single stage shelf is formed. Such a shelf is formed of 40 stages. It is possible to mount one glass substrate W in a horizontal position on the shelf of each stage.

A louver type shutter 11 is provided on the front side (the left side of the surface of FIG. 1) of the furnace body 10. The shutter 11 is configured by stacking a plurality of louvers in multiple stages. Each louver is provided with a lift driving mechanism (not shown), and the lift is possible for each louver. When the transport robot outside the drawing carries out the glass substrate W with respect to the furnace main body portion 10, only the portion facing the shelf that is the port of entry and exit is used as an access opening, which is approximately the same as that of the shelf. The louver at the height position rises. In this way, the opening at the time of carrying in / out of the glass substrate W can be made as minimum as necessary, and the leakage of the thermal energy accompanying carrying out of carrying out can be minimized. Moreover, when driving the louver of the lower part of the shutter 11 relatively, since the louver of the upper end is driven also in connection with the louver, it is necessary to provide the drive mechanism which obtains a larger output as the lower louver.

On the side surface of the furnace body 10, hot air inlet 12 for introducing hot air into the heat treatment space therein and a hot air exhaust port 14 for exhausting the hot air are provided to face each other. That is, hot air supplied from one side of the body main body 10 flows into the heat treatment space in the horizontal direction along the surface of the glass substrate W and flows to the opposite side. The hot air inlet 12 and the hot air vent 14 are provided at a height position corresponding to the entire multi-stage shelf that accommodates at least the glass substrate W among the inner wall surfaces of the furnace body 10. For this reason, a homogeneous firing process can be performed by supplying uniform hot air to the plurality of glass substrates W accommodated in the furnace body portion 10.

The circulation path 20 communicates the hot air exhaust port 14 and the hot air inlet 12 of the body main body 10 to circulate the hot air discharged from the body main body 10 to the body main body 10. It is a flow path through which gas can be supplied again. In the middle of the path of the circulation path 20, the catalyst filter unit 70, the adsorption tower 30, the circulation fan 40, and the main heater 52 are interposed. In 1st Embodiment, the catalyst filter part 70 is provided in the circulation path 20 to the adsorption tower 30 downstream from the furnace main body part 10. As shown in FIG. In addition, the upstream side of the circulation path 20 is a side close to the hot air exhaust port 14 of the furnace body 10, and the downstream side is a side close to the hot air inlet 12.

The catalyst filter unit 70 is platinum (Pt) or platinum rhodium (Pt) which functions as a catalyst for a metal filter composed of a metal mesh (in the first embodiment, a stainless steel mesh) having excellent heat resistance. The catalyst filter 71 which carried the particle | grains of -Rh) is provided. The catalyst filter unit 70 has a function as a catalyst for decomposing organic matter contained in hot air and a filter for removing particles.

Two adsorption towers 30 and 30 are provided in parallel in the middle of the circulation path 20. That is, the circulation path 20 branches into two flow paths 20a and 20b in a part of the path, and an adsorption tower 30 is provided in each of the two flow paths 20a and 20b which are branched. . The two flow paths 20a and 20b branched bifurcated again. Each adsorption tower 30 is filled with an adsorbent (activated carbon in the first embodiment) that adsorbs carbon dioxide (CO ₂ ) and water (H ₂ O). As the hot air flowing through the circulation path 20 passes through the adsorption tower 30, carbon dioxide and moisture are removed from the hot air.

In addition, each of the two adsorption towers 30 is provided with a bypass line 34 for recovering carbon dioxide and water, and a regeneration heater 33 for releasing the adsorbed carbon dioxide and water from the adsorbent. It is laid. When the adsorbent which adsorbed carbon dioxide and water is heated by the regeneration heater 33, carbon dioxide and water adsorbed from the adsorbent are released. The bypass line 34 recovers carbon dioxide and water released from the adsorbent by applying a pressure difference in the opposite direction to the flow paths 20a and 20b of the circulation path 20 to the adsorption tower 30.

Two adsorption towers 30 and 30 are alternatively used. Specifically, only one of the two branched flow paths 20a and 20b is selectively opened, and the hot air flowing through the circulation path 20 passes through only one of the two adsorption towers 30. Such flow path switching is performed by four butterfly dampers 31a, 31b, 32a, and 32b. When the butterfly dampers 31a and 31b are opened and the butterfly dampers 32a and 32b are closed, the flow path 20a is opened so that only the adsorption tower 30 on the left side of the ground of FIG. 1 is selectively used. On the contrary, when the butterfly dampers 32a and 32b are opened and the butterfly dampers 31a and 31b are closed, the flow path 20b is opened so that only the adsorption tower 30 on the right side of the ground of FIG. 1 is selectively used. . That is, the butterfly dampers 31a, 31b, 32a, and 32b serve as switching means for selectively switching the hot air flow paths 20a and 20b so that hot air passes through either of the two adsorption towers 30 and 30. Function.

The circulation fan 40 is provided with the motor (not shown) and the turning blade which rotates the turning blade, and the circulation airflow of the hot air which goes to the downstream side from the upstream side in the circulation path | route 20 (namely, the hot air exhaust pipe 14). Airflow to the hot air inlet 12 from)). The main heater 52 is a heat source for heating hot air circulating through the circulation path 20 by generating heat by energization.

The metal filter 54 is attached to the hot air inlet 12 of the furnace body 10. That is, the metal filter 54 is provided in the end of the circulation path 20, and the hot air outlet of the metal filter 54 is directly connected to the hot air inlet 12 of the furnace body part 10. . The metal filter 54 removes the particle | grains contained in hot air, and makes it the clean hot air.

The hardware configuration of the control unit 90 provided in the substrate baking furnace is the same as that of a general computer. That is, the control unit 90 stores a CPU that performs various arithmetic processing, a ROM that is a read-only memory that stores basic programs, a RAM that stores and reads and writes various information, and a control application and data. Magnetic disks and the like are provided. The control part 90 is electrically connected with each of four butterfly dampers 31a, 31b, 32a, and 32b, and controls those operations. Moreover, the control part 90 also controls the operation | movement of each operation mechanism (circulation fan 40, the main heater 52, the lift drive mechanism of the shutter 11, etc.) of the whole board | substrate baking furnace.

Next, the operation contents of the circulation type substrate firing furnace having the above configuration will be described. First, during the firing process, the conveying robot sequentially brings the glass substrate W into the furnace body part 10 at a predetermined interval and passes it to the shelf at a predetermined stage. The glass substrate W mounted on the fork constituting the shelf is heated up to the firing temperature by the hot air from the hot air inlet 12. Then, the glass substrate W in which the predetermined firing time has elapsed in the body main body 10 is carried out by the transport robot.

In the case where the to-be-encased material loaded on the glass substrate W is the color ink as in the present embodiment, the heated air is circulated so that the furnace main body portion 10 becomes an air atmosphere. It becomes inert gas atmosphere, such as nitrogen gas (that is, heating inert gas circulates). In any case, the organic solvent contained in the glass substrate W on the glass substrate W is volatilized or oxidized by firing to generate a large amount of organic matter and dissipate into the atmosphere in the furnace body portion 10. The heat atmosphere containing the organic substance is discharged as hot exhaust gas (hot air) from the hot air exhaust mechanism 14 of the furnace body 10.

The heat exhaust exhausted from the hot air exhaust 14 is circulated through the circulation path 20 by the circulation fan 40. In this circulation process, the hot air discharged from the hot air exhaust port 14 is first supplied to the catalyst filter unit 70. As the discharged hot air passes through the catalyst filter unit 70, decomposition reactions of organic substances contained in the hot air occur. Specifically, organic matter is decomposed into water and carbon dioxide. In the first embodiment, since the hot air passes through the catalyst filter 71 in which the catalyst particles are supported on the metal filter formed of the metal mesh, the contact efficiency between the exhausted hot air and the catalyst is increased, and the decomposition efficiency of the organic matter is increased. It can increase. In addition, even if the substance which solidified the organic substance and the sublimate which pass in a particle state in the hot air is contained, these substances are collected by the catalyst filter 71.

As in the first embodiment, when the to-be-encased object is a color ink, heated air is circulated as hot air, and thermal decomposition and oxidative decomposition of organic matter occur simultaneously in the catalyst filter unit 70. For this reason, the temperature of the catalyst filter 71 rises further by the heat | fever which generate | occur | produces by oxidative decomposition, and can improve the decomposition efficiency of organic substance further. In addition, when the to-be-encased material is a metal wiring material, since the inert gas (nitrogen gas) heated as hot air circulates, only the thermal decomposition of organic substance arises in the catalyst filter part 70. Further, even when the calcination process is performed in an inert gas atmosphere, an oxidative atmosphere supply mechanism for auxiliary supply of oxygen (or air) to the catalyst filter unit 70 is provided, and the thermal decomposition and oxidation of organic matter in the catalyst filter 71 are performed. Both decomposition may occur so that the decomposition efficiency of organic substance may be improved.

As described above, in the catalyst filter unit 70, organic matter is decomposed into water and carbon dioxide. These decomposition products generated by the decomposition are included as a gaseous phase in the hot air. If the concentration of these in the hot air becomes too high, there is a fear that the firing treatment may be hindered. For this reason, two adsorption towers 30 and 30 are provided in the circulation path 20 in the circulation type substrate baking furnace of 1st Embodiment. The adsorption tower 30 is filled with activated carbon therein, and the hot air passes through, so that moisture and carbon dioxide, which are decomposition products, are adsorbed and removed. Thereby, the concentration of water vapor and carbon dioxide in the hot air does not increase more than necessary, and the substrate baking furnace can be stably operated for a long time.

The two adsorption towers 30 and 30 are installed in parallel in the middle of the circulation path 20, and the hot air flow paths 20a and 20b have four butterfly dampers 31a and 31b so that only one of them passes therethrough. , 32a, 32b). Therefore, the hot air through which the organic matter is decomposed through the catalyst filter unit 70 is introduced into one of the two adsorption towers 30 and 30 to remove water and carbon dioxide.

In the adsorption tower 30 on which the hot air passes, the adsorption capacity of the activated carbon gradually decreases, so that moisture and carbon dioxide cannot be sufficiently removed by adsorption. For this reason, the adsorption tower 30 used at an appropriate timing is switched. That is, the control part 90 controls the timing of switching of four butterfly dampers 31a, 31b, 32a, and 32b so that hot air may pass through two adsorption towers 30 alternately. As a timing for switching the adsorption tower 30 to be used, the operation time of the adsorption tower 30 may be switched when a predetermined time has elapsed, and when the concentration of water vapor or carbon dioxide contained in the hot air exceeds a predetermined value. You may make it switch.

After the switching of the adsorption tower 30 to be used is performed, the regeneration treatment of the adsorption tower 30 used up to that time is performed. The regeneration treatment heats the adsorbent by the regeneration heater 33 to release the adsorbed moisture and carbon dioxide, and passes the pressure difference in the opposite direction to the circulation line 20 by the bypass line 34 to the adsorption tower 30. It is good to restore the adsorption capacity by recovering the water and carbon dioxide removed by addition. The control unit 90 may automatically control the temperature of the reheating heater 33 at this time. In addition, as a regeneration process, the activated carbon of the adsorption tower 30 may be replaced only with a new one.

Then, the four butterfly dampers 31a, 31b, 32a, and 32b are switched by the control unit 90 again so that the hot air passes through the adsorption tower 30 where the regeneration process is completed and the adsorption capacity is restored. And the regeneration process of the other adsorption tower 30 is performed similarly. Thus, when two adsorption towers 30 and 30 are used alternately, it becomes possible to operate continuously, without stopping a board | substrate baking furnace.

Hot air from which moisture and carbon dioxide are removed from the adsorption tower 30 is discharged to the main heater 52 by the circulation fan 40 and reheated. The hot air heated up by the main heater 52 is supplied to the metal filter 54. In the metal filter 54, the organic matter remaining without being completely decomposed into the catalyst filter unit 70 is also removed, so that the cleanliness of the hot air can be further improved. The hot air passing through the metal filter 54 is again supplied from the hot air inlet 12 to the inside of the furnace body 10.

In the substrate baking furnace of 1st Embodiment, the hot air discharged from the furnace main-body part 10 flows into the catalyst filter part 70 as it is, and the organic substance contained in a hot air is decomposed | disassembled. Therefore, a separate heater for heating the catalyst is unnecessary, and heat loss can be reduced. Moreover, since the baking temperature inside the furnace main body part 10 can be adjusted by control of only the main heater 52, temperature control becomes easy and a stable baking temperature can be obtained.

<2. Second embodiment>

Next, a second embodiment of the present invention will be described. FIG. 2 is a diagram showing the overall configuration of a circulating substrate baking furnace of a second embodiment. In FIG. 2, the same code | symbol is attached | subjected about the element same as 1st Embodiment. The substrate firing furnace of the second embodiment differs from the first embodiment in that the catalyst filter unit 70 includes a light source 72 in addition to the catalyst filter 71.

In the second embodiment, titanium oxide (TiO ₂ ) serving as a photocatalyst is mixed in a part of the catalyst supported by the catalyst filter 71. The light source 72 of the catalyst filter part 70 irradiates light to the catalyst filter 71. The photocatalyst supported on the catalyst filter 71 exhibits catalysis by receiving light from the light source 72. The remaining configuration of the substrate firing furnace of the second embodiment is the same as that of the first embodiment.

The operation contents of the substrate firing furnace of the second embodiment are also substantially the same as those of the first embodiment, so that heat loss can be reduced and stable firing temperature can be obtained, similarly to the first embodiment. In the second embodiment, light is irradiated to the catalyst filter 71 from the light source 72 at an appropriate timing. In this way, the photocatalyst of the catalyst filter 71 receives the light and exhibits catalysis, so that the organic substance remaining on the metal filter partially decomposed efficiently. That is, a kind of cleaning process can be performed by irradiating light to the catalyst filter 71 from the light source 72.

<3. Third embodiment>

Next, a third embodiment of the present invention will be described. FIG. 3 is a diagram showing an overall configuration of a circulation type substrate firing furnace of a third embodiment. In FIG. 3, the same code | symbol is attached | subjected about the element same as 1st Embodiment. The point that the circulating substrate baking furnace of 3rd Embodiment differs from 1st Embodiment is the arrangement position of the catalyst filter part 70. FIG.

As shown in FIG. 3, in 3rd Embodiment, the catalyst filter part 70 is provided in the circulation path 20 until it reaches the furnace main body part 10 downstream from the main heater 52. As shown in FIG. . The remaining configuration of the substrate firing furnace of the third embodiment is the same as that of the first embodiment.

In the third embodiment, the hot air discharged from the hot air exhaust port 14 of the furnace body part 10 and circulated in the circulation path 20 by the circulation fan 40 receives the main heater 52 from the adsorption tower 30. Through the catalyst filter 70 is introduced. Since hot air immediately after being heated by the main heater 52 flows into the catalyst filter part 70, the catalyst temperature of the catalyst filter part 70 also becomes high temperature, and organic matter contained in the hot air is decomposed with high efficiency. . That is, by arrange | positioning the catalyst filter part 70 in the rear end of the main heater 52, the temperature fall of the hot air from the main heater 52 to the catalyst filter part 70 is reduced, and the catalyst filter part 70 is reduced. ) To increase the decomposition efficiency. When the atmosphere containing oxygen or hot air is circulated as hot air, the catalytic filter unit 70 simultaneously causes thermal decomposition and oxidative decomposition of organic matter. For this reason, the temperature of the catalyst filter 71 rises further by the heat | fever which generate | occur | produces by oxidative decomposition, and the decomposition efficiency of organic substance can be made higher.

Even in the third embodiment, a separate heater for heating the catalyst is unnecessary, and heat loss can be reduced. Moreover, since the baking temperature inside the furnace main body part 10 can be adjusted by control of only the main heater 52, temperature control becomes easy and a stable baking temperature can be obtained.

<4. Fourth embodiment>

Next, a fourth embodiment of the present invention will be described. 4 is a diagram showing the overall configuration of a circulating substrate baking furnace of a fourth embodiment. In FIG. 4, the same code | symbol is attached | subjected about the element same as 2nd Embodiment and 3rd Embodiment. The difference from the third embodiment in that the circulating substrate baking furnace of the fourth embodiment is that the catalyst filter unit 70 includes a light source 72 in addition to the catalyst filter 71.

In the fourth embodiment, similarly to the third embodiment, the catalyst filter unit 70 is provided in the circulation path 20 from the main heater 52 to the furnace main body unit 10 downstream. As in the second embodiment, titanium oxide (TiO ₂ ) serving as a photocatalyst is mixed in part of the catalyst supported by the catalyst filter 71. The light source 72 provided with the catalyst filter part 70 irradiates light to the catalyst filter 71. The photocatalyst supported on the catalyst filter 71 exhibits catalysis by receiving light from the light source 72. The remaining configuration of the substrate firing furnace of the fourth embodiment is the same as that of the third embodiment.

The operation contents of the substrate firing furnace of the fourth embodiment are also substantially the same as those of the third embodiment, and thus, similar to the third embodiment, the heat loss can be suppressed to a minimum and a stable firing temperature can be obtained. In the fourth embodiment, the light is irradiated to the catalyst filter 71 from the light source 72 at an appropriate timing. In this way, the photocatalyst of the catalyst filter 71 receives the light and exhibits catalysis, so that the organic matter remaining on some metal filters can be efficiently decomposed. That is, a kind of cleaning process can be performed by irradiating light to the catalyst filter 71 from the light source 72.

<5. Fifth Embodiment>

Next, a fifth embodiment of the present invention will be described. FIG. 5 is a diagram showing an overall configuration of a circulating substrate baking furnace of a fifth embodiment. In FIG. 5, the same code | symbol is attached | subjected about the element same as 1st Embodiment. The point that the circulating substrate baking furnace of 5th Embodiment differs from 1st Embodiment is the arrangement position of the catalyst filter part 70. FIG.

As shown in FIG. 5, in 5th Embodiment, the catalyst filter part 70 is provided in each of the two flow paths 20a and 20b in which the adsorption towers 30 and 30 were provided. The remaining structure of the substrate baking furnace of the fifth embodiment is the same as that of the first embodiment.

In the fifth embodiment, the hot air discharged from the hot air exhaust port 14 of the furnace body part 10 and circulated in the circulation path 20 by the circulation fan 40 is absorbed from the catalyst filter unit 70 by the adsorption tower 30. It flows into the main heater 52 via. The passage procedure itself of this hot air is the same as that of 1st Embodiment. Therefore, similarly to the first embodiment, it is possible to control the heat loss less and to obtain a stable firing temperature.

In addition, since the catalyst filter part 70 is provided in each of the two flow paths 20a and 20b in 5th Embodiment, it uses by four butterfly dampers 31a, 31b, 32a, and 32b. At the same time, the adsorption tower 30 is switched, and the catalyst filter unit 70 to be used is also switched. For this reason, the regeneration treatment of the adsorption tower 30 can be performed, maintenance and cleaning of the catalyst filter unit 70 can be performed, and the maintenance of the catalyst filter unit 70 eliminates the need to stop the substrate firing furnace. Can improve the operation rate. In addition, it is not necessary to necessarily perform maintenance of the adsorption tower 30 and the catalyst filter part 70 at the same timing, and you may make it perform only one maintenance according to each maintenance cycle.

<6. Sixth embodiment>

Next, a sixth embodiment of the present invention will be described. FIG. 6 is a diagram showing an overall configuration of a circulation type substrate firing furnace of a sixth embodiment. In FIG. 6, the same code | symbol is attached | subjected about the element same as 2nd Embodiment and 5th Embodiment. The difference from the fifth embodiment in that the circulating substrate baking furnace of the sixth embodiment is that the catalyst filter unit 70 includes a light source 72 in addition to the catalyst filter 71.

In the sixth embodiment, like the fifth embodiment, the catalyst filter unit 70 is provided in each of the two flow paths 20a and 20b provided with the adsorption towers 30 and 30. As in the second embodiment, titanium oxide (TiO ₂ ) serving as a photocatalyst is mixed in part of the catalyst supported by the catalyst filter 71. The light source 72 of the catalyst filter part 70 irradiates light to the catalyst filter 71. The photocatalyst supported on the catalyst filter 71 exhibits catalysis by receiving light from the light source 72. The remaining configuration of the substrate firing furnace of the sixth embodiment is the same as that of the fifth embodiment.

The operation contents in the substrate firing furnace of the sixth embodiment are also substantially the same as those of the fifth embodiment, and thus, similar to the fifth embodiment, heat loss can be suppressed to a minimum, and a stable firing temperature can be obtained. In the sixth embodiment, light is irradiated to the catalyst filter 71 from the light source 72 at an appropriate timing. In this way, the photocatalyst of the catalyst filter 71 receives the light and exhibits catalysis, so that the organic substance remaining on the metal filter partially decomposed efficiently. That is, a kind of cleaning process can be performed by irradiating light to the catalyst filter 71 from the light source 72.

<7. Seventh embodiment>

Next, a seventh embodiment of the present invention will be described. In the seventh embodiment, an adsorption tower 60 having an adsorption material 61 for absorbing carbon dioxide at a relatively high temperature is provided in place of the adsorption tower 30 filled with an adsorbent for adsorbing carbon dioxide and water. FIG. 7: is a figure which shows the absorption tower 60 of 7th Embodiment. In FIG. 7, the same code | symbol is attached | subjected about the same element as 1st Embodiment.

The two absorption towers 60 and 60 are provided in parallel in the middle of the circulation path 20. Similarly to the first embodiment, the circulation path 20 is branched into two flow paths 20a and 20b in a part of the path, and an absorption tower (for each of the two flow paths 20a and 20b which are branched). 60) is installed. The two branched flow paths 20a and 20b join again. Each absorption tower 60 is equipped with the absorber 61 which absorbs carbon dioxide at comparatively high temperature. In the seventh embodiment, lithium silicate (Li ₄ SiO ₄ ) is used as the absorber 61. For example, as disclosed in Japanese Patent Laid-Open No. 2006-102561, lithium silicate absorbs carbon dioxide even in a temperature range from room temperature to 400 ° C. The firing temperature in the furnace body part 10 is generally 200 ° C to 300 ° C, which is within a temperature range in which lithium silicate absorbs carbon dioxide. Therefore, the absorber 61 can absorb and remove carbon dioxide from the hot air flowing through the circulation path 20.

Each absorption tower 60 is further provided with a discharge heater 62 for releasing the absorbed carbon dioxide from the absorber 61 and a recovery system 64 for recovering the carbon dioxide emitted from the absorber 61. . Lithium silicate has the property of releasing carbon dioxide when heated to a higher temperature than the temperature range for absorbing carbon dioxide. Therefore, when the release heater 62 heats the absorber 61 which absorbed carbon dioxide, the carbon dioxide absorbed from the absorber 61 is released. The recovery system 64 includes valves 63a and 63b, and recovers the carbon dioxide released from the absorber 61 by opening both valves 63a and 63b. Specifically, the carrier gas (for example, nitrogen gas) is supplied to the absorber 61 each time the valve 63b is opened. The carbon dioxide emitted from the heated absorbent 61 is recovered together with the carrier gas by opening the valve 63a.

Like the first embodiment, the two absorption towers 60 and 60 are alternatively used. That is, the four butterfly dampers 31a, 31b, 32a, and 32b alternately switch the flow paths 20a and 20b of the hot air, so that the hot air flowing through the circulation path 20 is the two absorption towers 60 and 60. Only one of them). Except that the adsorption tower 30 was replaced with the absorption tower 60, the structure of the substrate baking furnace of 7th Embodiment is the same as that of 1st Embodiment.

The operation contents of the substrate firing furnace of the seventh embodiment are also substantially the same as those of the first embodiment. That is, the hot air discharged from the hot air exhaust port 14 of the furnace body part 10 and circulated in the circulation path 20 by the circulation fan 40 passes through the absorption tower 60 from the catalyst filter unit 70. It flows into the phosphorus heater 52. Since the hot air discharged from the furnace body part 10 flows into the catalyst filter unit 70 as it is and organic matters contained in the hot air are decomposed, a separate heater for heating the catalyst is unnecessary, and heat loss can be reduced. . Moreover, since the baking temperature inside the furnace main body part 10 can be adjusted by control of only the main heater 52, temperature control becomes easy and a stable baking temperature can be obtained.

In addition, the butterfly dampers 31a, 31b, 32a, and 32b switch the hot air circulating in the circulation path 20 so as to pass only one of the two absorption towers 60 and 60. Therefore, the hot air through which the organic matter is decomposed through the catalyst filter unit 70 is introduced into one of the two absorption towers 60 and 60 to remove carbon dioxide.

As in the first embodiment, the absorption tower 60 used at an appropriate timing is switched. That is, the control part 90 controls the timing of switching of four butterfly dampers 31a, 31b, 32a, and 32b so that hot air may communicate with two absorption towers 60 and 60 alternately.

After switching of the absorption tower 60 to be used is performed, the regeneration process of the absorption tower 60 used up to that time is performed. The regeneration process of the absorption tower 60 heats the absorber 61 by the discharge heater 62, and opens valves 63a and 63b. As a result, carbon dioxide absorbed from the absorber 61 is released, and the released carbon dioxide is recovered by the recovery system 64.

In addition, the four butterfly dampers 31a, 31b, 32a, and 32b are switched by the controller 90 again so that the hot air passes through the absorption tower 60 after the regeneration process is completed. And the regeneration process of the other absorption tower 60 is performed similarly. In this way, it becomes possible to operate continuously, without stopping a board | substrate baking furnace.

The absorption tower 60 can be used in place of the adsorption tower 30 in all of the first to sixth embodiments (FIGS. 1 to 6). That is, the circulation path 20 may be a form in which a trap tower for trapping carbon dioxide and / or water is provided in each of the two flow paths 20a and 20b branched in a part of the path.

<8. Variation Example>

As mentioned above, although embodiment of this invention was described, this invention can be variously changed except having mentioned above, unless the meaning is deviated from the meaning. For example, in each of the above embodiments, the trap tower (the adsorption tower 30 or the absorption tower 60) is provided in parallel in the middle of the circulation path 20, and the other trap tower is being used while the trap tower is being used. Although the regeneration process is performed to improve the operation rate of the substrate firing furnace, only one trap top may be provided in the middle of the circulation path 20. In this manner as well as in each of the above embodiments, the heat loss can be suppressed to a minimum and a stable firing temperature can be obtained.

In the second, fourth, and sixth embodiments, the catalytic filter 71 may be caused to use a light from an indoor luminaire or the like, without providing the light source 72.

In addition, although activated carbon was used as the adsorbent of the adsorption tower 30 in 1st-6th embodiment, it is not limited to this, What is necessary is just a material which adsorbs carbon dioxide and / or water, For example, silica gel ( silica gel) or zeolite may be used. As the adsorbent, an inorganic membrane such as a polymer membrane or a zeolite membrane, a silica membrane, or a carbon membrane may be used.

In addition, instead of the metal filter 54 of each said embodiment, you may use sintered ceramics. In addition, as long as the catalytic filter part 70 has a function as a filter sufficiently, and can remove an organic substance and a particle reliably, the metal filter 54 does not necessarily need to be installed. However, as in the first, second, fifth, and sixth embodiments, when the circulation fan 40 and the main heater 52 are provided on the downstream side of the catalyst filter unit 70, particles generated therefrom are removed. It is preferable to install a metal filter 54 at the hot air inlet 12 of the furnace body 10 for the purpose of doing so.

In each of the above embodiments, the circulation path 20 of the substrate firing furnace is completely closed. However, an atmosphere exchange mechanism for introducing a new atmosphere while discharging part of the atmosphere may be provided.

The number of glass substrates W that can be accommodated in the furnace body portion 10 of the substrate firing furnace is not limited to 40, but may be any number.

The substrate to be subjected to the firing process by the circulating substrate baking furnace according to the present invention is not limited to the glass substrate W, but may be a semiconductor wafer. In addition, the to-be-fired material mounted on a board | substrate is not limited to a color ink or a metal wiring material, A material for banks, A material for ITO electrodes (transparent electrodes of indium tin oxide), For organic insulating films It may be a material, a light-transmitting organic film material, various inks having an organic solvent, or the like.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the whole structure of the circulation type substrate baking furnace of 1st Embodiment.

It is a figure which shows the whole structure of the circulation type substrate baking furnace of 2nd Embodiment.

It is a figure which shows the whole structure of the circulation type substrate baking furnace of 3rd Embodiment.

It is a figure which shows the whole structure of the circulation type substrate baking furnace of 4th Embodiment.

It is a figure which shows the whole structure of the circulation type substrate baking furnace of 5th Embodiment.

It is a figure which shows the whole structure of the circulation type substrate baking furnace of 6th Embodiment.

7 is a view showing an absorption tower of a seventh embodiment.

[Description of the code]

10: body part

12: hot air inlet

14: hot air exhaust

20: circulation path

20a, 20b: Euro

30: adsorption tower

31a, 31b, 32a, 32b: butterfly damper

40: circulation fan

52: main heater

54: metal filter

60: absorption tower

62: discharge heater

64: recovery meter

70 catalyst catalyst

71: catalytic filter

72: light source

90: control unit

Claims (10)

As a circulating substrate baking furnace which circulates hot air and calcinates a substrate, A main body part for accommodating a substrate therein; A circulation path for circulating hot air discharged from the furnace body part and supplying it again to the furnace body part; A circulation fan installed in the circulation path to circulate hot air; A main heater for heating hot air circulating in the circulation path; A catalyst filter unit provided in the circulation path and having a main filter carrying a catalyst; And a trap means installed in the circulation path to trap carbon dioxide and / or moisture. The method of claim 1, The trap means includes two trap towers installed in parallel in two flow paths branched into two branches and rejoined in the middle of the circulation path. Switching means for alternatively switching the two flow paths so that hot air passes through either one of the two trap towers; And a switching control unit for controlling the timing of switching of said switching means. The method of claim 2, The two trap towers are two adsorption towers which adsorb at least one of carbon dioxide and water. The method of claim 2, The two trap towers are two absorption towers absorbing carbon dioxide. The method of claim 4, wherein Each of the two absorption towers, Absorber of carbon dioxide, A discharge heater for releasing the absorbed carbon dioxide from the absorber; And a recovery system for recovering carbon dioxide released from the absorber. 6. The method according to any one of claims 1 to 5, The catalytic filter section is disposed in the circulation path between the furnace main body section and the downstream side to the trap means. 6. The method according to any one of claims 1 to 5, The catalytic filter part is provided between the main body part and a downstream side of the main heater in the circulation path to the furnace main body part. The method according to any one of claims 2 to 5, And said catalytic filter portion is provided in each of said two flow paths. The method of claim 1, The catalyst includes a photocatalyst, The catalyst filter unit includes a light irradiation means for irradiating light to the photocatalyst. The method of claim 1, And a metal filter is provided at the hot air inlet of the furnace body.

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