TW201522257A - Glass manufacturing method - Google Patents

Abstract

The present invention provides a glass manufacturing method which can prolong the service life of a furnace having a wall installed with electrodes. The glass manufacturing method relates to a method for melting glass by introducing glass raw material into a melting furnace having a wall laminated with at least one pair of electrodes 200 and a plurality of refractory bricks 111c. The glass manufacturing method disclosed in this invention is characterized in that the raw material composition of the electrode 201a making up the electrode 200 contains stannic oxide and the refractory bricks 111c in periphery can movably hold the electrode 201a by a manner of locating the front end of the electrode 201 at a predetermined position.

Description

Glass manufacturing method

The present invention relates to a method of producing glass. Furthermore, the present invention relates to a glass substrate for a flat panel display (FPD), and more particularly to a method for producing a glass substrate for a liquid crystal display (LCD).

Radiation heat and direct energization of gas flames have been used as heating methods for molten glass in glass melting furnaces. In the direct current conduction mode, the molten glass is energized between the opposing electrodes, and the molten glass is heated by the Joule heat generated during the energization.

In the production of the glass of the glass substrate for FPD, the above-mentioned gas flame and direct energization method have been used as the heating method of the molten glass.

However, since the alkali metal-containing component in the glass substrate for FPD is limited to a small amount of glass, or the alkali-free glass which does not substantially contain an alkali metal component has a high electric resistance, in order to perform heating by direct energization (direct Electric heating), it is necessary to increase the size of the electrode.

At this time, since platinum which has been used as an electrode for direct current heating has been a rare metal and has a high price, there is a problem in cost when the electrode is increased in size. In Patent Document 1 (Japanese Patent Laid-Open Publication No. 2003-292323), tin oxide or molybdenum, which is an inexpensive platinum electrode material, is used for the electrode.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2003-292323

However, an electrode using tin oxide or molybdenum has a problem that a portion in contact with the molten glass is lost due to corrosion. Generally, the glass melting furnace is a structure in which a refractory is laminated, and the tin oxide or molybdenum electrode is incorporated in the wall of the glass melting furnace in a state surrounded by the refractory. At this time, if the tin oxide or molybdenum electrode is lost due to corrosion, there is a case where the refractory deposited on the tin oxide or molybdenum electrode is slumped, and the glass melting furnace becomes unusable.

Therefore, an object of the present invention is to provide a method for producing a glass which can extend the life of a furnace including an electrode.

In the method for producing a glass according to the present invention, the glass raw material is introduced into a melting furnace to melt the glass, and the melting furnace is provided with at least a pair of electrodes and a plurality of refractories; and the method for producing the glass is characterized in that: The counter electrode contains a material containing a metal having electrical conductivity at a high temperature, and the electrode is held by the surrounding refractory so that the front end of the electrode is located at a specific position so that it can be moved by pushing.

Further, since the electrode can be moved by pushing so that the front end of the electrode is located at a specific position, even if the electrode is corroded, the refractory deposited on the electrode can be prevented from collapsing. Therefore, the present invention can provide a method for producing a glass capable of extending the life of a glass melting furnace equipped with an electrode. Further, it is preferable that the specific position is the position near the wall surface of the inside of the glass melting furnace at the front end of the electrode. As long as the front end of the electrode is located near the inner wall surface of the above glass melting furnace, the refractory laminated on the electrode does not collapse even if the electrode is corroded.

Further, in the method for producing a glass of the present invention, it is preferable that the metal having conductivity at a high temperature contains at least one selected from the group consisting of tin oxide, molybdenum, and zirconium oxide.

Further, in the method for producing a glass of the present invention, it is preferred to carry out the above in a melting furnace. The refractory collapse prevention mechanism.

Further, in the method for producing a glass according to the present invention, it is preferable that the collapse preventing means is disposed adjacent to the electrode and disposed on the other electrode.

Further, in the method for producing a glass of the present invention, it is preferred that the temperature of the molten glass in the melting furnace is 1500 ° C or higher.

Further, in the method for producing a glass of the present invention, a composite obtained by integrating an electrode system with a plurality of electrodes is preferable.

Further, in the method for producing a glass of the present invention, it is preferred that the electrode is a composite obtained by integrating a plurality of electrodes, and is pressed from the outside of the melting furnace.

Further, in the method for producing a glass according to the present invention, the glass raw material is introduced into a melting furnace to melt the glass, and the melting furnace is provided with at least a pair of electrodes and a plurality of refractories; and the pair of electrodes includes a conductive material. The material of the metal, the method for producing the glass, comprising: heating the glass present in the gap between the electrode and the surrounding refractory when the electrode is moved to a specific position, wherein the electrode is The manner in which the front end of the electrode is located at a specific position is maintained by the surrounding refractory so as to be movable.

Further, in the method for producing a glass according to the present invention, the glass raw material is introduced into a melting furnace to melt the glass, and the melting furnace is provided with at least a pair of electrodes and a plurality of refractories; and the pair of electrodes includes a conductive material. The material of the metallic metal is held in such a manner that the electrode is biased against the internal pressure of the glass in the melting furnace in such a manner that the front end of the electrode is located at a specific position.

Further, in the method for producing a glass of the present invention, the obtained glass can be formed into a sheet shape to produce a glass substrate for a flat panel display.

According to the method for producing a glass of the present invention, it is possible to provide a method for producing a glass in which a glass melting furnace is equipped with an electrode, even if the electrode is corroded by molten glass. Loss, the refractory layer laminated on the electrode does not collapse, thereby prolonging the life of the furnace.

100‧‧‧Glass manufacturing equipment

101‧‧‧melting tank (melting furnace)

111‧‧‧ wall

111a‧‧‧ wall

111b‧‧‧ wall

111c‧‧‧Fire-resistant bricks (refractory)

200‧‧‧electrode

201‧‧‧ electrodes

201a‧‧‧electrode

201b‧‧‧electrode

202‧‧‧Connector

204‧‧‧Connector

Figure 1 is a block diagram of a block diagram of a glass manufacturing apparatus and a glass manufacturing step.

Figure 2 is a detailed view of a melting tank (melting furnace).

Figure 3 is a detailed view of the electrode.

Figure 4 is a schematic diagram of the movement of the electrodes.

Fig. 5 (a) and (b) are schematic views showing the addition of a new electrode.

Fig. 6 (a) and (b) are schematic views showing a modification of the embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. Further, the following description relates to an example of the present invention, and the present invention is not limited thereto.

(1) Overall composition

Hereinafter, a method for producing a glass plate for a glass substrate of a flat panel display will be described as an embodiment of the method for producing a glass of the present invention.

(1-1) Glass raw materials

In order to manufacture a glass sheet in accordance with the present invention, the glass raw material is first mixed in such a manner as to become a desired glass composition. For example, in the case of manufacturing a flat panel display, particularly a glass substrate for a liquid crystal display (LCD), it is preferred to mix the raw materials in such a manner as to have the following composition.

(a) SiO ₂ : 50 to 70% by mass, (b) B ₂ O ₃ : 5 to 18% by mass, (c) Al ₂ O ₃ : 10 to 25% by mass, (d) MgO: 0 to 10% by mass (e) CaO: 0 to 20% by mass, (f) SrO: 0 to 20% by mass, (o) BaO: 0 to 10% by mass, (p) RO: 5 to 20% by mass (wherein R is selected At least one of Mg, Ca, Sr, and Ba), (q) R' ₂ O: 0 to 2.0% by mass (wherein R' is selected from at least one of Li, Na, and K), (r) The total of at least one of the metal oxides such as tin oxide, iron oxide, and cerium oxide is 0.05 to 1.5% by mass.

(1-2) Summary of glass manufacturing steps

Hereinafter, an outline of each step for manufacturing glass will be described with reference to FIG.

First, a melting step is carried out in which the raw material of the glass mixed into the above composition is supplied to the melting tank 101 and heated to 1500 ° C or higher. The heated raw material is melted to become molten glass.

In the next clarification step, the above molten glass is clarified by the clarification tank 102. Specifically, the molten glass is heated in the clarification tank 102, the gas component contained in the molten glass forms a bubble, or the molten glass is vaporized and is emitted to the outside of the molten glass.

In the subsequent stirring step, the molten glass is stirred in the stirring tank 103 by the stirring blade (not shown) provided in the stirring tank 103, thereby homogenizing.

In the subsequent forming step, the molten glass is supplied to the forming device 104. In the forming device 104, the glass is formed into a plate-shaped glass. In the present embodiment, the molten glass is continuously formed into a sheet shape by an overflow down draw method. The sheet-like glass after the forming is cut into a glass plate.

(2) Detailed composition

(2-1) Details of the melting tank

Hereinafter, the melting tank 101 will be described with reference to FIG.

The melting tank 101 includes a liquid tank B composed of a refractory such as fire-resistant brick and an upper space A. The melting tank 101 is a pair of electrodes 200 (one of which is not shown) and a plurality of fire resistance The brick 111c is configured such that the electrode and the fire-resistant brick are members constituting the melting tank. A burner 300 that burns a gas such as a fuel and oxygen to emit a flame is provided on a wall surface of the upper space A of the melting tank 101. The burner 300 heats the refractory constituting the upper space A by the combustion gas, and heats the glass raw material by heating the radiant heat emitted from the high-temperature refractory. In the liquid tank B, a plurality of pairs of electrodes 200 (one of which is not shown) are provided on the opposite walls 111a and 111b. The paired electrodes 200 (one of which is not shown) are disposed on the mutually opposing walls 111a, 111b of the liquid bath B of the melting tank 101. Specifically, an electrode 200 (not shown) is provided on the wall 111a at a position opposed to each of the electrodes 200 provided on the wall 111b. Here, the pair of the electrodes 200 has a structure in which it is divided into a positive electrode and a negative electrode, and a current flows between the positive and negative electrodes. Further, in this case, a positive/negative common electrode may be provided on the bottom surface of the liquid tank B, and the electrode on the wall surface may be paired with the positive and negative common electrodes on the bottom surface. FIG. 2 shows a case where three pairs of electrodes 200 (one of which is not shown) are provided. The molten glass is energized by the pair of electrodes 200, and Joule heat is generated from the molten glass itself. In the melting tank 101, the molten glass is heated to 1500 ° C or higher.

As shown in Fig. 3, the wall 111 is formed by laminating a plurality of fire-resistant tiles 111c and electrodes 201a. The electrode 200 is formed by laminating a plurality of electrodes 201a and is formed as an integral electrode 200, and is sandwiched between the fire-resistant bricks 111c and the fire-resistant bricks 111c. Specifically, the following plurality of electrodes 201a of the electrode 200 are laminated on the fire-resistant brick 111c. A plurality of electrodes 201a are further laminated on the plurality of electrodes 201a. The fire-resistant brick 111c is laminated around the electrode 201a of the laminated layer to hold the electrode 201a. Further, a fire-resistant brick 111c is laminated on the electrode 201a. Each of the fire-resistant tiles 111c has a substantially rectangular parallelepiped shape, and the electrode 201a also has a substantially rectangular parallelepiped shape. The refractory bricks 111c and the electrodes 201a are in contact with each other on their respective planes. The planes adjacent to each other form an angle of 90 or substantially 90. Therefore, a gap is hardly formed between the electrode 201a and the refractory brick 111c. The melting tank 101 receives a pressure toward the outside of the melting tank 101 by the molten glass G in the melting tank 101. Therefore, using a jack or the like not shown A fixed pressure that pushes into the melting tank 101 is applied to the outer wall of the melting tank 101. Further, a material such as a material to be used is not used between each of the laminated fire-resistant tiles 111c and each of the electrodes 201a, but an adhesive material may be used as needed.

(2-2) Details of the electrode

The electrode 200 and the electrode 201a will be described with reference to FIG. In the melting tank 101, the side of the molten glass G is set to be the inner side or the inner side with the wall 111 as a starting point, and the opposite side of the inner side is the outer side or the outer side.

3 is a schematic enlarged view of a wall 111 in which a portion of the electrode 200 is disposed. As shown in FIG. 3, the electrode 200 includes a plurality of electrodes 201a. The electrode 201a is a calcined body containing tin oxide or a calcined body containing tin oxide as a main component, and has a shape similar to a rectangular parallelepiped. A metal connector 202 for connecting the electrode 201a to the power source is attached to one end of the electrode 201a in the longitudinal direction (hereinafter referred to as the end). The electrode 201a is incorporated in the fire-resistant brick 111c so that the end faces the outer side of the wall 111 and the other end (hereinafter referred to as the front end) of the electrode 201a faces the molten glass G located further inside the wall 111. between. The electrode 200 shown in FIG. 3 includes a total of twelve electrodes 201a in which four electrodes 201a are arranged in the horizontal direction and four layers are stacked in the vertical direction. The front end of each electrode 201a is located at the same position as the vertical surface (wall surface X shown in FIG. 4) of the wall 111 which is in contact with the molten glass in the melting tank 101, or protrudes toward the molten glass G from the wall surface X. Set the location.

Further, the front end of the electrode 201a which is in contact with the molten glass G is subjected to a pressure toward the outside of the melting tank 101 by the molten glass in the melting tank 101. Therefore, a fixed pressure that is pushed into the melting tank 101 is applied to the end of the electrode 201a by a jack or the like (not shown). That is, the counter electrode is provided with a force that counteracts the internal pressure of the molten glass in the melting tank 101 and is held.

(2-3) Refractory collapse prevention mechanism

Hereinafter, the collapse prevention mechanism of the refractory of the present invention will be described. In the following, in the melting tank 101, the side where the molten glass G is present is set with the wall 111 as a starting point. Inside or inside, the opposite side of the inside is set to the outside or the outside.

As described above, the molten glass is heated to 1500 ° C or higher by the melting tank 101. However, the electrode 201a constituting the electrode 200 for energizing the molten glass is also heated by contact with Joule heat generated by energization or contact with the molten glass of high temperature. Regarding the heated electrode 201a, if the electrode 201a is damaged by corrosion, the front end of the electrode 201a becomes located further outside the wall surface X. As described above, a plurality of fire-resistant tiles 111c are laminated on the electrode 201a. Therefore, if the electrode 201a is worn out, there is a risk that the fire-resistant brick 111c laminated thereon will collapse. Further, in a state where the front end of the electrode 201a is located further outside the wall surface X, the fire-resistant brick 111c constituting the wall 111 becomes more energized than the molten glass, so that the wall 111 is corroded from the periphery where the electrode 200 is provided. .

Therefore, the front end of the electrode 201a is positioned such that the front end of the electrode 201a is at the same position as the wall surface X, or the front end of the electrode 201a is located on the inner side of the wall surface X, that is, on the side toward the molten glass, so that the front end of the electrode 201a is provided. It will not be located outside the wall X due to corrosion and loss. Specifically, first, the electrode 201a is heated. Since the electrode 201a is cooled by blowing air from the end, the electrode 201a is heated as long as the cooling is stopped. As described above, there is almost no gap between the electrode 201a and the refractory brick 111c. However, even if a small amount of molten glass is intruded between the electrode 201a and the refractory brick 111c, it solidifies. By heating the electrode 201a, the glass is heated to lower the viscosity. The glass having a reduced viscosity serves as a lubricating material for relaxing the friction between the electrode 201a and the refractory brick 111c. Next, a plurality of electrodes 201a are collectively pressed from the outer side of the wall 111 toward the inside of the wall 111, that is, the molten glass G in the melting tank 101 by a jack or the like, and are moved. At this time, the plurality of electrodes 201a are uniformly pressed from the outside of the melting furnace. The above pressing uses a worm jack to obtain the pressing force required for the movement of the electrode 201. Further, the above-mentioned required pressing force can calculate the required load based on the molten glass hydraulic pressure in the furnace and the weight of the oxidizing electrode. Thereby, the collapse of the fire-resistant brick 111c laminated on the electrode 201a, that is, the collapse of the wall 111 of the melting tank 101 can be prevented as much as possible. However, if the electrode 201a continues to be corroded, Then, the final electrode 201a is lost, and the electrode 201a which moves to the wall surface X or the inner side of the wall surface X gradually disappears. Therefore, a new electrode is disposed behind the electrode 200. Specifically, for example, as shown in FIG. 5(a), the electrode 201a is corroded and lost, so that the end of the electrode 201a no longer protrudes from the outer surface of the wall 111, or before, as shown in FIG. 5(b) The electrode 201b, which is a new electrode 201 different from the electrode 201a, is disposed such that its front end is in contact with the end of the electrode 201a. That is, a new other electrode 201b is added to the end of the existing electrode 201a. If the electrode 201b to be supplemented is damaged by corrosion, the new electrode 201b is replenished, and the replenishment may be repeated. Thereby, even if the life of the electrode 201a is exhausted, the collapse of the fire-resistant brick 111c, that is, the collapse of the wall 111 can be prevented as much as possible. That is, the life of the electrode 200 and the melting tank 101 can be extended.

When the new other electrode 201b is replenished to the end of the electrode 201a, the connector 202 attached to the end of each of the electrodes 201a is removed. After the new other electrode 201b is replenished to the end of the electrode 201a, the connector 202 is mounted at the end of the complemented electrode 201b. The end of the electrode 201b to be supplemented is pressed toward the end of the electrode 201a with a fixed pressure by a jack or the like so that the end of the electrode 201a is in contact with the front end of the electrode 201b.

Further, when the connector 202 is detached, it is necessary to stop the energization from the electrode 200, and in the case where the plurality of counter electrodes 200 are provided with the melting tank 101 of the three pairs of electrodes 200 as shown in FIG. 2, Each pair of electrodes 200 may be supplemented with a new electrode 201. Thereby, the replenishment of the electrode 201 can be carried out before the temperature of the molten glass G is lowered as much as possible.

(3) Features

(3-1)

In the above embodiment, the electrode 200 is provided between the laminated fire-resistant tiles 111c and held by the fire-resistant bricks 111c. That is, the electrode 200 is directly in contact with the fire-resistant brick 111c. Thereby, it is possible to form a gap with the wall 111 of the melting tank 101 as much as possible.

(3-2)

In the above embodiment, when the electrode 201 constituting the electrode 200 is damaged by corrosion, the electrode 201a is moved to the side of the molten glass G in the melting tank 101, and the front end of the electrode 201a is positioned at a specific position. The specific position means that the front end of the electrode is located near the wall surface inside the glass melting furnace. Specifically, the position near the wall surface on the inner side of the glass melting furnace is preferably the same position as the wall surface X on the inner side of the wall 111 or a position closer to the inner side, but it is only a layer of fire-resistant brick The position where the 111c does not fall down may be the outer side of the wall surface X of the wall 111. Thereby, the collapse of the fire-resistant brick 111c of the wall 111 can be prevented as much as possible, so that the life of the melting tank 101 can be extended. Further, if the front end of the electrode protrudes too far to the inner side of the wall surface X of the inner wall 111, the amount of corrosion of the electrode becomes large, and the life of the electrode becomes short, from the viewpoint of prolonging the life of the melting furnace not ideal.

(3-3)

In the above embodiment, a new electrode 201b is added to the end of the electrode 201a. That is, the other electrode is disposed adjacent to the rear of the electrode 200. That is, even if the electrode 201a is worn out, the new electrode 201, that is, the electrode 201b, can be continuously replenished, and the life of the electrode 200 is extended. Thereby, the collapse of the fire-resistant brick 111c of the wall 111 can be prevented as much as possible, thereby prolonging the life of the melting tank 101.

(3-4)

In the above embodiment, the electrode 200 includes a plurality of electrodes 201. Thereby, the electrode 200 larger than each of the electrodes 201 can be formed in a simple manner.

(4) Modifications

(4-1)

In the above embodiment, when the new electrode 201b is replenished to the end of the electrode 201a, it is necessary to remove the connector 202 attached to the end. However, in another embodiment, the connector 202 can be removed more easily. For example, as shown in FIG. 6, it is also possible to use the jack in such a manner that the connector unit 203 is in contact with the end of the electrode 201. The end of the counter electrode 201 is pressed, and the connector unit 203 is formed by mounting the connector 204 of the plurality of electrodes 201 together in an integrated frame or the like. Specifically, for example, a plurality of metal connectors 204 are mounted in a frame in which elongated members of an insulating system such as metal or wood are assembled in a lattice shape. The connector 204 is mounted in the lattice-like frame in such a manner that the contact portions of the plurality of connectors 204 and the electrodes 201 are arranged on the same plane. The contact portion of the plurality of connectors 204 with the electrode 201 is disposed at the same interval as the arrangement of the plurality of electrodes 201 included in the electrode 200. The connector unit 203 configured in this manner pushes the end of the electrode 201 with a jack or the like so that the contact portion of each connector 204 is in contact with the end of each electrode 201. Thereby, the connector 204 of the plurality of electrodes 201 can be quickly and easily attached and detached, and the electrode 201 can be quickly replenished. Therefore, the replenishment of the electrode 201 can be performed before the temperature of the molten glass G in the melting tank 101 is lowered as much as possible.

(4-2)

In the above embodiment, the electrode 201 is made of tin oxide. However, in another embodiment, the electrode 201 may be made of another metal as long as it has conductivity at a high temperature, and the electrode 201 preferably contains at least one selected from the group consisting of tin oxide, molybdenum, and zirconium oxide.

(4-3)

In the above embodiment, when the electrode 201 is eluted to the molten glass G faster, the life of the electrode 201 and the melting furnace 101 is shortened. Therefore, it is preferable to reduce the elution amount of the electrode 201. Since the temperature of the electrode 201 is higher, the elution amount of the electrode 201 is larger, so that the amount of elution of the electrode 201 can be suppressed by lowering the temperature of the electrode 201.

In order to reduce the elution amount of the electrode 201, it is preferable to arrange the front end of the electrode 201 at the same position as the wall surface X or at the outer side of the wall surface X. The wall surface X is the inner wall surface of the melting furnace 101 and is the surface of the fire-resistant brick 111c which is in contact with the molten glass G. The phrase "the same position as the wall surface X" means that the shortest distance from the wall surface X to the front end of the electrode 201 is less than 5 mm. The so-called "outer side of the wall X" means that the front end of the electrode 201 is preferably matched. It is preferably placed at a position other than the wall surface X by 5 mm or more, more preferably at a position other than the wall surface X by 7 mm or more, and more preferably at a position other than the wall surface X by 10 mm or more. Further, in order to prevent the molten glass G from leaking from the melting furnace 101, the front end of the electrode 201 is preferably 10 mm or more from the outer wall surface of the melting furnace 101, more preferably 15 mm or more, and still more preferably 20 mm or more.

By arranging the electrode 201 at the same position as the wall surface X or at the outer side of the wall surface X, the contact area between the electrode 201 and the molten glass G becomes small, and the front end of the electrode 201 is close to the temperature lower than the molten glass G. Since the outer wall surface of the melting furnace 101 is lowered, the temperature of the surface of the electrode 201 in contact with the molten glass G can be lowered, and the amount of elution of the electrode 201 can be reduced. Further, the outer wall surface of the melting furnace 101 may be cooled. Further, in this case, the current density at the corner portion of the tip end of the inflow electrode 201 is reduced, and the temperature at the corner portion of the tip end of the electrode 201 is lowered, so that the elution amount of the electrode 201 can be reduced.

From the viewpoint of reducing the elution amount of the electrode 201, it is preferable to arrange the front end of the electrode 201 at a position outside the wall surface X. Thereby, the temperature of the electrode 201 can be further reduced as compared with the case where the front end of the electrode 201 is disposed at the same position as the wall surface X, so that the elution of the electrode 201 can be further suppressed. For example, the front end of the electrode 201 may be disposed at the outer side of the wall surface X, and the position of the front end of the electrode 201 may be further outside due to corrosion, so that the front end of the electrode 201 is located further outside the wall surface X. In this way, the electrode 201 is pushed inward.

Moreover, from the viewpoint of reducing the elution amount of the electrode 201 and the refractory brick 111c, it is preferable to arrange the front end of the electrode 201 at the same position as the wall surface X. When the front end of the electrode 201 is disposed on the outer side of the wall surface X, the corner portion of the refractory brick 111c is concentratedly corroded, and the possibility of dissolving foreign matter such as zirconium from the refractory brick 111c is improved. The front end of the electrode 201 is disposed at the same position as the wall surface X, and this can be suppressed. For example, the front end of the electrode 201 may be initially disposed at the same position as the wall surface X, and the position of the front end of the electrode 201 may be further outside than the wall surface X due to corrosion, so that the electrode 201 is made. The electrode 201 is pushed inwardly in such a manner that the front end is located at the same position as the wall surface X.

Further, as another example, the front end of the electrode 201 may be initially placed at the same position as the wall surface X, and the position of the front end of the electrode 201 may be further outside the wall surface X due to corrosion so that the front end of the electrode 201 is located at the front end. The wall surface X is pressed further inwardly, and the front end of the electrode 201 may be disposed at the outer side of the wall surface X, and the position of the front end of the electrode 201 may be further outside due to corrosion. Thereafter, the electrode 201 is pressed inwardly so that the front end of the electrode 201 is located at the same position as the wall surface X.

111‧‧‧ wall

111c‧‧‧Fire-resistant bricks (refractory)

200‧‧‧electrode

201‧‧‧ electrodes

201a‧‧‧electrode

202‧‧‧Connector

Claims (12)

A method for producing a glass obtained by introducing a glass raw material into a melting furnace to melt a glass, wherein the melting furnace is provided with at least a pair of electrodes and a plurality of refractories; and the method for producing the glass is characterized in that: The counter electrode contains a metal having electrical conductivity at a high temperature; the electrode is held by the surrounding refractory so that the front end of the electrode is located at a specific position so that it can be moved by pushing. The method for producing a glass according to claim 1, wherein the metal having conductivity at a high temperature comprises at least one selected from the group consisting of tin oxide, molybdenum, and zirconium oxide. The method for producing a glass according to claim 1 or 2, wherein the refractory collapse prevention mechanism is implemented in the melting furnace. The method of producing a glass according to claim 3, wherein the collapse prevention mechanism is disposed adjacent to the electrode and disposed on the other electrode. The method for producing a glass according to any one of claims 1 to 4, wherein the temperature of the molten glass in the melting furnace is 1500 ° C or higher. The method for producing a glass according to any one of claims 1 to 5, wherein the electrode is a composite obtained by integrating a plurality of electrodes. The method for producing a glass according to any one of claims 1 to 6, wherein the electrode is a composite obtained by integrating a plurality of electrodes, and the electrode is pressed from the outside of the melting furnace. The method for producing a glass according to any one of claims 1 to 7, wherein the specific position of the tip end of the electrode is at the same position as the surface of the refractory which is in contact with the molten glass, or is higher than the surface of the refractory The position of the inside. The method for producing a glass according to any one of claims 1 to 7, wherein the specific position of the front end of the electrode is the same as the surface of the refractory which is in contact with the molten glass. The position, or the position outside the surface of the refractory. A method for producing a glass obtained by introducing a glass raw material into a melting furnace to melt a glass, wherein the melting furnace is provided with a pair of electrodes and a plurality of refractories; and the method for producing the glass is characterized in that: The electrode includes a metal having conductivity at a high temperature; and the method for manufacturing the glass includes the step of heating the glass present in the gap between the electrode and the surrounding brick when the electrode is moved to a specific position, the electrode system The surrounding refractory is movably held in such a manner that the front end of the electrode is located at a specific position. A method for producing a glass obtained by introducing a glass raw material into a melting furnace to melt a glass, wherein the melting furnace is provided with at least a pair of electrodes and a plurality of refractories; and the method for producing the glass is characterized in that: The counter electrode contains a metal having conductivity at a high temperature; and the electrode is provided with a force against the internal pressure of the glass in the melting furnace so that the electrode has a predetermined position at a predetermined position. A method for producing a glass substrate for a flat panel display, which is obtained by forming a glass produced by the method for producing a glass according to any one of claims 1 to 11 into a sheet shape, thereby producing a glass substrate for a flat panel display.