JP2000356471A - Continuously conveying baking furnace - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the variation of a baking temperature in a furnace by constituting of at least two or more partitioned heating chambers and constituting to continuously convey a material to be baked through the chambers. SOLUTION: A base plate 19 for an FDP is heat treated. The heat treatments are sequentially moved from a first heating chamber 1 through a second heating chamber and a third heating chamber 3 and set so that an atmospheric temperature of the third chamber becomes 600 deg.C at the highest. After baking, rollers 16 are reversed to reversely convey a baking material from the chamber 3 to the chamber 2 and the chamber 1, and to cool the material. As a result, the plate 19 can be baked as a predetermined object by suitably setting and controlling the heating conditions of the chambers 1, 2 and 3. Accordingly, the influence of a gas flow in association with the movement of the material in the continuously baking furnace can be checked.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous transfer firing furnace for firing flat display panel (hereinafter referred to as "FDP") substrates and the like, and particularly to a small and suitably used test firing furnace for FDP substrates and the like. The present invention relates to a continuous transfer firing furnace that can be used.

[0002]

2. Description of the Related Art In recent years, a plasma display panel, which is a type of FDP, has been attracting attention as a main product for large screens, and is being developed by various companies. In manufacturing such a plasma display panel, which is a kind of FDP, a firing furnace is indispensable.
It is used in an annealing process for a glass substrate, a thick film process using a printing technique for electrodes, barrier ribs, dielectrics, phosphors, and the like.

In the baking step, for example, in a thick film process, it is naturally required to make the baking temperature uniform and clean in a furnace. Mass production and cheap production are required.

On the other hand, in firing the above-described FDP substrate, a small and simple firing furnace for testing is required. As the firing furnace for the test, the following two systems are usually employed. The first method is to confirm the size of the test baked product as the actual machine size using a batch furnace, and the second is to reduce the size of the test baked product and the calcination furnace in a similar manner.

However, in a test using a batch furnace of the first type, it is impossible to confirm the influence of a gas flow accompanying movement (transfer) of a fired product from a heating chamber to another heating chamber in a continuous furnace such as a roller hearth type. There is a problem that is. Further, in the small roller hearth type test firing furnace as referred to in the second method, there is a drawback that the temperature distribution as a whole of a large product cannot be demonstrated, and no problems can be found in mass production. In addition, it is impossible to determine the difference in the effect on the firing between the vicinity of the furnace wall and the center of the furnace.

[0006]

Accordingly, the present invention provides
The present invention has been made in view of the above-described problems, and an object thereof is to provide a continuous transfer firing furnace that has a small variation in firing temperature in the furnace, ensures cleanness in the furnace, and can be downsized as a test firing furnace. Is to do.

[0007]

Means for Solving the Problems According to the present invention, a roller hearth type baking furnace is composed of at least two or more divided heating chambers, and each of these heating chambers is covered. There is provided a continuous transfer and firing furnace characterized by being configured to be able to continuously transfer fired articles to each other. More specifically, the firing furnace of the present invention includes a furnace body as an outer wall, a panel cover made of a heat-resistant steel sheet for protecting the furnace body, a heat insulating material layer covering the inside of the furnace body, and the heat insulating material. It is preferable that a heater for heating is arranged between the heat insulating material layer and the lining and at the top and bottom of the firing furnace between the heat insulating material layer and the lining.

In the continuous transfer firing furnace of the present invention, the lining of the furnace is made of a Si—SiC-based material, and a gas radiant tube heater or a combination of a gas radiant tube heater and an electric heater is provided outside the lining. It is preferable to arrange and heat. Also,
The above-described continuous transfer firing furnace of the present invention can be particularly preferably applied as a test firing furnace for FDP substrates.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A continuous transfer firing furnace according to the present invention will be described in detail based on embodiments shown in the drawings, but the present invention is not limited to these embodiments. FIG. 1 is a schematic sectional view showing an embodiment of the continuous transfer firing furnace according to the present invention, and FIG. 2 is a sectional view taken along line AA of FIG. In FIG. 1, reference numeral 10 denotes a roller hearth type continuous transfer firing furnace,
The first heating chamber 1, the second heating chamber 2, and the third heating chamber 3 are composed of three divided heating chambers, and each of these heating chambers 1, 2, and 3 independently sets and controls the temperature. In addition to the configuration, the object to be fired 19 such as an FDP substrate can be continuously conveyed to each other.

Referring to FIG. 2, reference numeral 10 denotes a roller hearth type continuous transfer firing furnace. The firing furnace 10 includes a furnace body 11 as an outer wall and a panel cover made of a heat-resistant steel sheet for protecting the furnace body 11. 12, a heat insulating material layer 13 covering the inside of the furnace body 11, and a lining 14 provided inside the heat insulating material layer 13.
And an electric heater 1 for heating at the top and bottom of the furnace.
5 are arranged. Further, rollers 16, setters 17, spacers 18, beams (not shown), and the like are used as members in the furnace, and a PDP substrate 19, which is a fired product, is placed on the setters 17.

In the roller hearth type continuous transfer firing furnace having the above-described structure, the article to be fired 19 is transferred from the first heating chamber 1 to the second heating chamber 2 and the third heating chamber 3 in order. In the first heating chamber 1 and the second heating chamber 2, the temperature of the article to be fired 19 is raised at a predetermined heat curve, and the article to be fired 19 is fired in the third heating chamber 3 at the highest heating temperature. Next, after firing the article to be fired 19 in the third heating chamber 3,
By rotating the roller 16 in the reverse direction, the third heating chamber 3
To the second heating chamber 2 and the first heating chamber 1 in reverse. At this time, the second heating chamber 2 and the first heating chamber 1 are set so that the baked product has a predetermined cooling heat curve (temperature-falling curve). By reciprocating between the second heating chamber 2 and the third heating chamber 3, it is possible to perform appropriate firing. Further, as another embodiment, the transfer between the first heating chamber 1 and the second heating chamber 2 and the transfer between the second heating chamber 2 and the third heating chamber 3 are performed in different systems, so that the first heating chamber 1 and the second heating chamber 3 are separated. Second heating chamber 2 and second heating chamber 2
The second heating chamber 2 can be used as two types of firing furnaces in which the second heating chamber 2 is shared with each system of the third heating chamber 3.

As described above, the continuous transfer firing furnace of the present invention is of a batch type for a product to be fired, and is a continuous firing furnace. Further, according to the continuous transfer and firing furnace of the present invention, since the number of the heating chambers is two or more, the object to be fired (or the fired article) is sent from the heating chamber to the heating chamber, so that the transfer in the continuous firing furnace ( It is possible to confirm the influence of the gas flow accompanying the transfer. In order to confirm the influence of the gas flow, it is preferable that the baking furnace is configured to have three to four chambers, preferably three heating chambers. Also, by using a test firing furnace that matches the product dimensions,
The dimensional effect in actual production can be confirmed.

Further, in the continuous transfer and firing furnace of the present invention, the lining 14 is made of a Si—SiC-based material, and the rollers 16, the setter 17, the spacer 18, It is preferable that at least the setter 17 and the beam among the beams are made of a Si—SiC-based material.
It is more preferable that the rollers 16, the spacers 18, and other members in the furnace are also made of a Si-SiC-based material.

As described above, when the material of the lining of the firing furnace and the members in the furnace are made of Si—SiC-based material,
Since the i-SiC-based material has an extremely high thermal conductivity of about 150 W / m · K, the heating efficiency by the heater 15 is excellent, and since the lining material is a uniform surface heating source, the gas radiant tube is apt to be locally heated. Even in a firing furnace using a heater, a rod-shaped electric heater, or the like, the variation in the firing temperature in the furnace can be reduced. Also, S
Since the i-SiC-based material has high bending strength and a large Young's modulus, there is almost no load deformation.
Since the porosity of the SiC-based material can be controlled to be as fine as about 1% or less, it is excellent in oxidation resistance, and the lining is oxidized and deteriorated to generate fine powder. Cleanness in the furnace can be ensured.

The Si—SiC-based material can be manufactured, for example, as follows. First, a predetermined amount of C powder, S
An iC powder, a binder, water or an organic solvent are kneaded and molded to obtain a molded article having a desired shape. Next, this molded body is
A method of permeating and impregnating the molten metal Si into the compact by placing the metal body in a reduced pressure inert gas or vacuum under a metal Si atmosphere can be mentioned. Also, Si-SiC
As another method for producing a system material, a graphite sheet or a carbon sheet is placed in a crucible or the like filled with metal Si, heated to melt the metal Si, and the above-mentioned sheet is formed by utilizing the capillary effect. Carbon and Si are reacted with each other to generate SiC and leave excess Si. In addition, as a Si-SiC-based material, for example, a SiC-based sintered body described in Japanese Patent No. 2642573 can be exemplified.

The Si—SiC-based material is a material whose base material is a SiC material and whose pores are infiltrated and impregnated with Si, and whose composition includes Si and SiC. Specifically, 0.5 to 50% by weight of Si,
Those containing 99.5% by weight of SiC are preferred in terms of strength, thermal shock resistance and the like.

[0017]

EXAMPLES Hereinafter, the present invention will be further described with reference to specific examples. (Example 1) α-SiC powder (average particle size 2 μm) 100
10 parts by weight of carbon powder (average particle size 1
μm), 2 parts by weight of a binder and 3 parts by weight of water were added and kneaded.
pressurized with a pressure of f / cm ² , outer diameter 38mmφ × 5mm
A (thickness) × 2400 mm (length) molded article was obtained. While contacting the obtained molded body with metal Si in a vacuum, 180
The temperature was held at 0 ° C. for 2 hours, and a roller for a roller hearth type continuous transfer firing furnace was manufactured from a Si—SiC sintered body.

Next, the roller is moved to a width of 2200 m.
m, and two FDP substrates were stacked on this roller. The setter for the FDP substrate had a surface area of 1200 mm × 1500 mm and weighed 135 kg per setter. The roller pitch was 250 mm, and four rollers received one setter. In addition, the same material as the roller was used for the setter and the spacer for stacking, and the same Si-SiC sintered body was used.

Under the above conditions, the FDP substrate is
The heat treatment was carried out in a roller hearth type continuous transfer firing furnace shown in FIG. Heat treatment is performed by sequentially moving from the first heating chamber to the second heating chamber and the third heating chamber, setting the ambient temperature of the third heating chamber to be a maximum of 600 ° C., and rotating the roller in reverse after firing. Thereby, the fired product was conveyed from the third heating chamber to the second heating chamber and the first heating chamber in reverse, and cooled. The heat curve is shown in FIG. As a result, by appropriately setting and controlling the heating conditions of the first heating chamber, the second heating chamber, and the third heating chamber, the FDP substrate could be fired as intended. Therefore, the influence of the gas flow accompanying the movement in the continuous firing furnace could be confirmed, and the firing state near the side wall of the firing furnace and the central part of the furnace could also be confirmed.

The temperature distribution of the FDP substrate in the substrate in the holding step at the maximum temperature of 600 ° C. and in the slow cooling step was measured and found to be within ± 2 ° C. Furthermore, Si-Si in a class 100 clean booth
C plate (100mm × 100mm × 5mm (thickness))
In the sample cooled to 22 ° C. after the temperature was raised to 00 ° C., there was no change in the numerical value of the generation of foreign matter in the laser type particle counter, and it was found that the degree of cleanness was secured.

[0021]

As described above, according to the continuous transfer sintering furnace of the present invention, it is possible to confirm the influence of the gas flow accompanying the movement in the sintering furnace, and to set the test sintering furnace according to the product dimensions. Thereby, the dimensional effect in actual production can be confirmed. Therefore, it can be used very suitably as a test firing furnace. Further, it is possible to provide a baking furnace which has a small variation in the baking temperature in the furnace and can ensure the cleanness.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing one embodiment of a continuous transfer firing furnace according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a heat curve in the continuous transfer firing furnace of Example 1.

[Explanation of symbols]

1 ... first heating chamber, 2 ... second heating chamber, 3 ... third heating chamber, 1
0: Roller hearth type continuous transfer firing furnace, 11: Furnace body, 1
2 ... panel cover, 13 ... heat insulating material layer, 14 ... lining, 1
5: electric heater for heating, 16: roller, 17: setter, 18: spacer, 19: FDP substrate.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // H01J 9/48 H01J 9/48

Claims (4)

[Claims] 1. A baking furnace of a roller hearth type, comprising at least two or more divided heating chambers, each of which is capable of continuously transporting articles to be fired. A continuous transfer and firing furnace characterized in that: 2. A baking furnace, comprising: a furnace body as an outer wall; a panel cover made of a heat-resistant steel sheet for protecting the furnace body; a heat insulating material layer covering the inside of the furnace body; The continuous transfer firing furnace according to claim 1, further comprising a lining provided, wherein a heating heater is disposed between the heat insulating material layer and the lining and at the top and bottom of the firing furnace. 3. The heating apparatus according to claim 1, wherein the furnace lining is made of a Si—SiC-based material, and a gas radiant tube heater or a combination of a gas radiant tube heater and an electric heater is disposed outside the lining for heating. 2. The continuous transfer firing furnace according to 2. 4. The continuous transfer firing furnace according to claim 1, wherein the number of heating chambers is three.