KR20060047991A - Method for removing warping of glass surface-plate - Google Patents

Abstract

This invention makes it a subject to remove efficiently the distortion of a glass plate efficiently and reliably.

A plurality of glass plates are stacked and both sides are sandwiched by a heat-resistant flat plate having a higher flatness and higher flatness than the glass plate.At this time, the same plate as the heat-resistant flat plate is inserted for each predetermined number of glass plates between the plurality of stacked glass plates. The distortion of the glass plate is removed by heating and slow cooling the glass plate while pressing the outermost heat resistant flat plates.

Glass platen, flat display panel

Description

How to remove the distortion of the glass plate {METHOD FOR REMOVING WARPING OF GLASS SURFACE-PLATE}

1 is an explanatory diagram showing an embodiment of the present invention.

2 is a graph showing a temperature profile when heating a glass plate;

3 is an explanatory diagram showing another embodiment.

4 is an explanatory diagram showing an example in which distortion of the actual glass surface plate is removed.

5 is a graph showing a heating temperature profile of a glass plate.

It is explanatory drawing which shows the measurement result of the amount of distortion of a glass surface plate.

7 is a graph showing the amount of warpage of the glass platen.

8 is an explanatory diagram showing a processing apparatus for removing distortion of a glass surface plate;

* Description of the symbols for the main parts of the drawings *

1: glass platen

2 carbon plate

3: press stone

11: Glass plate undercarriage set part

12: heating furnace

13: control unit

14: glass surface plate conveyance part

15: glass plate receiving part

16: carbon plate storage

17: glass plate end lamination part

16: push stone storage

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a method of eliminating distortion of a glass surface plate, and more particularly, glass used in a heat treatment process when manufacturing a flat display panel such as a plasma display panel (PDP) or a liquid crystal display (LCD). It relates to a method of eliminating distortion of the surface plate.

In a line for manufacturing a flat display panel such as a PDP, a dielectric layer is formed on the front side substrate and the back side substrate, particularly when manufacturing an AC type PDP.

The dielectric layer is usually formed by applying a paste-like dielectric material to a substrate, mounting the substrate on a glass plate, and bringing it into a baking furnace, and firing the paste-like dielectric material.

Although the glass base used in the baking process of this dielectric layer uses what was produced from heat resistant glass, the distortion by heat generate | occur | produces during several uses.

However, when distortion occurred in the glass surface plate, since there was no means for correcting it, it was necessary to discard this surface plate and replace it with a new glass surface plate.

Moreover, although various methods are known about the flattening method of plate glass (for example, refer Unexamined-Japanese-Patent No. 8-231233 and 11-11973), the glass used for the heat processing process of a flat display panel Tables have different distortions one by one, and the emergence of a method for efficiently and reliably removing such distortions was required.

This invention is made | formed in view of such a situation, and it is providing the method of removing the distortion of a glass plate efficiently and reliably.

The present invention relates to a method for removing distortion of a glass plate on which a glass substrate for a flat display panel is mounted in a heat treatment step in manufacturing a flat display panel, wherein a plurality of glass plates are stacked, and both sides thereof are larger than the glass plate and have high flatness. The glass plate is heated by inserting the same plate as the heat-resistant plate for every predetermined number of glass plates between the plurality of overlapped glass plates at that time, and pressing the outermost heat-resistant plates to each other. It is a distortion removal method of the glass surface plate which removes the distortion of a glass surface plate by slow cooling.

In the present invention, a plurality of glass plates are stacked, and both sides thereof are sandwiched by a heat resistant flat plate having a higher flatness while being larger than the glass plates. It is preferable to select a material having a small thermal expansion coefficient as the heat resistant flat plate having a higher flatness than that of the glass plate. From this viewpoint, for example, a carbon plate made of isotropic graphite having a coefficient of thermal expansion smaller than that of the glass plate can be used as the heat resistant plate. Specifically, as the heat resistant flat plate, a carbon plate made of isotropic graphite: JIS B0405 intermediate, surface finish: ▽ ▽ can be used.

In this invention, the plate same as a heat resistant plate is inserted for every predetermined number of glass plates between the multiple sheets of glass platen which overlapped. As a predetermined number, about 1 to about 5 sheets can be applied. Since the distortion of the glass plate can be best removed by one sheet, and the highest throughput per unit time is five, the appropriate number of sheets is selected according to the degree of distortion to be removed. The same plate as the heat resistant plate is substantially the same material and the same flatness as the heat resistant plate, and means that the thickness is different from that of the heat resistant plate. This flat plate usually uses a thickness thinner than the heat resistant flat plate placed on the outermost side of the glass surface plate.

In the present invention, after that, the glass plate is heated while pressing the outermost heat-resistant flat plates and slowly cooled to remove the distortion of the glass plate. Although this pressurization is not specifically limited, It is cost-effective to employ | adopt the method of pressurizing by raising a press stone on the heat-resistant flat plate of the uppermost stage piled in a stage. In this case, the pressed stone may be any one as long as the heat resistance is higher than that of the heat resistant plate, and for example, a metal lump or the like can be applied.

Although heating of a glass surface plate is not specifically limited, The method of carrying in a laminated heat resistant flat plate and a glass surface plate into a heating furnace, and heating can be applied. As the heating furnace, various conventionally known electric furnaces can be applied. In the step of heating the glass plate, when a carbon plate or the like is used as the heat resistant flat plate, it is preferable to make the furnace an oxygen free atmosphere, specifically, a nitrogen atmosphere or a hydrogen atmosphere.

It is preferable to perform heating of a glass plate by heating in a predetermined temperature profile. It is necessary to perform heating temperature in this heating process at temperature higher than the temperature which the distortion of a glass plate is ensured.

In this invention, after removing the distortion of a glass surface plate, you may further perform the process of carrying out the blast process for finishing surface roughness to a glass surface plate.

Moreover, before removing the distortion of a glass plate, you may also perform the process of performing a blast process for preventing a flaw from occurring when removing a distortion in a glass plate.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on the Example shown to drawing. In addition, this invention is not limited by this, A various deformation | transformation is possible.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows one Example of the distortion removal method of the glass surface plate of this invention. In this figure, 1 is a glass plate, 2 is a carbon plate, and 3 is a push stone.

The glass surface plate 1 is for mounting a glass substrate in the heat treatment process at the time of manufacturing a flat display panel. This heat treatment step is a firing step when a dielectric layer is formed on a glass substrate on the front side or a back side, or a firing step when a partition wall is formed on a glass substrate on the back side.

In the present Example, 11 carbon plates 2 are laminated | stacked, and the glass platen 1 is arrange | positioned between each carbon plate 2. Therefore, the carbon plate 2 and the glass plate 1 are laminated | stacked differently. And the press stone 3 is arrange | positioned on the uppermost carbon plate 2. The number of laminated sheets of the carbon plate 2 is not limited to this and may be 11 or less sheets or 11 or more sheets.

The carbon plate 2, the glass plate 1 and the pressing stone 3 are loaded into the heating furnace while being laminated in this state, heated to a predetermined temperature profile, and thereafter, the glass plate 1 is removed by slow cooling. do.

In the glass surface plate 1 of the present embodiment, distortion, warpage (curvature), irregularities, and the like occur due to use in the manufacturing process of the flat display panel. The glass plate 1 to be applied has a size of 1200 mm × 1600 mm, thickness: 5 mm, and surface polishing treatment: Rmax × 3-6 μm. The distortion guarantee temperature is 850 ° C. As this glass surface plate, what was produced using glass, such as Neoceram (trademark) N-0 or N-11 by Nippon Denki Glass Corporation, is applicable, for example. In addition, instead of the glass surface plate, it is also possible to apply general plate glass.

The carbon plate 2 is a heat resistant surface plate which is larger than the glass surface plate 1 and has high flatness. Heat-resistant temperature is higher than the glass plate 1, and is 1000 degreeC or more. As the carbon plate 2, it is important to select a material having a small thermal expansion coefficient. The carbon plate 2 is size: 1300 mm x 1700 mm, material: isotropic graphite, tolerance: JIS B0405 intermediate, surface finish:? As this carbon plate, the thing made from Tokai carbon company is applicable, for example.

As for the carbon plate 2, the lowermost one is about 35-45 mm thick, the uppermost one is about 25-35 mm thick, and the middle one is about 10-25 mm thick.

As for the press stone 3, about 300 Kg is used with respect to 10 sheets of glass plates. In this embodiment, it is 300 kg. The material may be any heat resistant material of about 1000 ° C., for example, a metal mass such as soft iron is used.

It is a graph which shows the temperature profile of the heating furnace at the time of heating a glass plate.

When heating the glass base 1, the glass base 1 is carried in a heating furnace, and the inside of a furnace is made into nitrogen atmosphere in order to prevent combustion of a carbon plate. In other words, the furnace is heated in a nitrogen atmosphere while nitrogen is introduced to purge the air. As a heating furnace, an electric furnace called a stand-alone type elevator furnace, etc. can be used. In addition, a furnace can also be set as hydrogen atmosphere. In this case, hydrogen is introduced first by vacuuming the inside of the furnace.

The heating profile is gradually heated from room temperature to 850 ° C. to maintain 850 ° C. for about 8 hours, after which the heating is stopped and slowly cooled in a furnace to 350 ° C., when it is about 350 ° C., it is transferred to a cooling chamber and becomes about 20 ° C. Until slow cooling. The heating temperature is set to 850 ° C because the guaranteed temperature (maximum safe use temperature) of the glass plate 1 is about 850 ° C. By heating to the temperature higher than this guaranteed temperature, the distortion, curvature, unevenness | corrugation, etc. of the glass plate 1 are forcibly removed.

In this way, a plurality of carbon plates are laminated, and a glass plate is sandwiched between the carbon plates one by one, and a push stone is placed on the uppermost carbon plate to a temperature higher than the temperature at which the warp of the glass plate is guaranteed. By heating and slow cooling after that, it becomes possible to planarize several sheets of glass plate with different magnitude | size of unevenness uniformly and at once.

3 is an explanatory diagram showing another embodiment.

In this embodiment, a plurality of glass base plates 1 are sandwiched and sandwiched between the carbon plates 2. Specifically, four sheets are overlapped. Then, the pressing stones 3 are placed on the uppermost carbon plate 2. Since the pressed stone 3 uses about 300 Kg of glass sheet 10 sheets, it is 450 Kg.

Thereby, the regeneration treatment ability (the number of sheets per unit time) of the glass surface plate can be improved. The number of sheets of the glass plate 1 sandwiched between the carbon plate 2 and the carbon plate 2 is preferably about five from the viewpoint of reliably removing the distortion of the glass plate 1. If it is more than that, although the processing number per unit time will improve, the probability of not being able to fully remove the distortion of the glass plate 1 will become high.

It is explanatory drawing which shows the example which removes the distortion of a glass plate actually.

In this example, four carbon plates 2 were laminated. The carbon plate was size: 1300 mm x 1700 mm, material: isotropic graphite, tolerance: JIS B0405 intermediate, cotton finish:?

The carbon plate 2 has a thickness of 40 mm at the bottom, a thickness of 30 mm at the top, and a thickness of 25 mm at the middle.

20 glass sheets 1 were sandwiched between the carbon plates 2. Specifically, seven glass plates 1 are sandwiched between the bottom and the second carbon plate 2 from below, and seven glasses between the second and third carbon plates 2 from below. The plate 1 was inserted, and six glass plates 1 were sandwiched between the third and top carbon plates 2 from below.

This glass plate 1 is size: 1200 mm x 1600 mm and thickness: 5 mm, and performs surface grinding | polishing process: Rmax x 3-6 micrometers.

The pressing stone 3 used 350 kg of iron lumps.

The carbon plate and the glass plate laminated | stacked as mentioned above were carried in in the vacuum furnace, and the furnace inside was made into nitrogen atmosphere, and it heated by the temperature profile as shown in FIG. That is, heating started a process from the temperature of 40 degrees C or less, and raised the temperature to 850 degreeC over about 5 hours. And after hold | maintaining at the temperature of 850 degreeC for 10 to 11 hours, heating is stopped and slow cooled in a furnace, and when it reaches 350 degreeC, it returns to a cooling chamber in a vacuum heating furnace, and cools for about 3 hours in a cooling chamber. did.

The measurement result of the amount of distortion before and after removing the distortion of a glass plate is shown in FIG. FIG. 6A is before correction (before distortion removal) and FIG. 6B is after correction (after distortion removal). As shown in this measurement result, the distortion is clearly removed after the correction of the distortion.

7 is a graph showing the amount of distortion before and after removing the distortion of the glass surface. (A) of FIG. 7 is before distortion removal, and FIG. 7 (b) is after distortion removal. In the graph, the difference between before and after distortion removal is evident.

Subsequently, with respect to the glass plate from which the distortion was removed as described above, an abrasive such as glass beads or alumina beads is blown to perform blasting, and the surface roughness of the glass plate is finished.

In this process, in order to finish the glass surface from which distortion was removed to predetermined surface roughness (Ry3-6 micrometers), the following process is implemented.

[First Step] Blast Treatment

Second Process High Pressure Cleaning

Third Step Ultrasonic Cleaning with Pure Water

[4th process] pure rinse

[Fifth Step] Air Blow

[Sixth Step] Drying (120 ° C × 1 hour)

Although the blasting process was performed about the glass surface plate which remove | eliminated distortion in the above, since a glass surface plate is used in a heat processing process, a foreign material adheres and becomes a protrusion in many cases. For this reason, a flaw is easy to generate | occur | produce in a glass surface when the glass surfaces overlap, or when a glass surface and a carbon plate are overlapped. Therefore, before removing the distortion of a glass surface plate, you may make it remove the foreign material adhering to a glass surface surface by the above blast processing.

It is explanatory drawing which shows the processing apparatus for removing the distortion of a glass surface plate.

This processing apparatus is comprised from the glass surface plate set part 11, the heating furnace 12, the control part 13, and the glass surface plate conveyance part 14. The glass surface plate conveyance part 14 is comprised from the glass surface surface receiving part 15, the carbon plate accommodating part 16, the glass surface plate | tip lamination part 17, and the push stone storage part 16. As shown in FIG.

The warp generated glass platen is conveyed to the glass platen undercarriage set portion 11 and is handed over to the glass platen receiving unit 15. Thereafter, in the glass surface plate lamination portion 17, the carbon plate accommodated in the carbon plate storage portion 16 and the glass plate received by the glass surface receiving portion 15 are alternately laminated. Then, an appropriate weight of a pressing stone is selected from the plurality of pressing stones accommodated in the pressing stone accommodating portion 18, and the pressing stones are placed on the uppermost carbon plate, and are carried into the heating furnace 12 in that state.

When heating and slow cooling are complete | finished, it is carried out to the glass surface plate | board laminated part 17, where a press stone is removed and is accommodated in the press stone accommodating part 18, and a carbon plate is removed and is accommodated in the carbon plate accommodating part 16 here. . The glass platen is sent to the glass plate receiving unit 15 and returns to the glass plate undercarriage set portion 11. These controls are performed in the control unit 13.

In this way, one or more glass platen is sandwiched between laminated carbon plates, a press stone is put on a topmost carbon plate and brought into a heating furnace, and after cooling, it cools slowly and removes the distortion of a glass platen, The distortion of the glass plate of the hawk can be removed by one treatment. In addition, since the carbon plate is inserted between the glass plates, even if the plurality of glass plates have different glass plates, the distortions of all the glass plates can be evenly removed.

In addition, the distortion removal of the glass surface plate may be integrally formed in the manufacturing line of the flat panel so as to be executed automatically. Specifically, the glass surface plate after a baking process is conveyed to the above-mentioned processing apparatus, and distortion removal is processed automatically.

According to this invention, the distortion of several glass platen can be removed by one process. Moreover, since the heat resistant flat plate higher in flatness than a glass plate is inserted between glass platens, even if the glass plate of several sheets has a different distortion, the distortion of all the glass platens can be removed uniformly.

Claims (7)

As a method of eliminating distortion of a glass surface plate on which a glass substrate for a flat display panel is mounted in a heat treatment step when producing a flat display panel, A plurality of glass plates are piled up, and both sides are sandwiched by a heat resistant flat plate having a higher flatness while being larger than the glass plate, In that case, the same plate as the said heat resistant plate is inserted for every predetermined number of glass platen between the said multiple sheets of glass platen, The distortion of the glass plate is removed by heating the glass plate while pressing the outermost heat-resistant flat plates and slow cooling. As a distortion removal method of the glass plate which mounts the glass substrate for flat display panels in the heat processing process at the time of manufacturing a flat display panel, A plurality of glass plates are piled up, and both sides are sandwiched by a heat resistant flat plate having a higher flatness while being larger than the glass plate, In that case, the same plate as the said heat resistant plate is inserted for every predetermined number of glass platen between the said multiple sheets of glass platen, The distortion method of the glass surface plate which removes the distortion of a glass surface surface by heating a glass surface and pressing-cooling while pressing the outermost heat resistant flat plates in nitrogen atmosphere. The method according to claim 1 or 2, The step of inserting the same plate as the heat resistant plate for each predetermined number of glass plates is performed by inserting the same plate as the heat resistant plate for each sheet of the glass plate. The method according to claim 1 or 2, The said heat resistant flat plate is a carbon surface plate which consists of isotropic graphite which has a coefficient of thermal expansion smaller than a glass surface plate, The distortion method of the glass surface plate characterized by the above-mentioned. The method according to claim 1 or 2, The heating temperature in the heating process of the said glass surface plate is a temperature higher than the temperature which the distortion of a glass surface plate is ensured, The distortion method of the glass surface plate characterized by the above-mentioned. The method according to claim 1 or 2, After removing the distortion of a glass surface plate, the glass surface surface further comprises the process of carrying out the blast process for finishing surface roughness, The distortion method of the glass surface table characterized by the above-mentioned. The method according to claim 1 or 2, A method of removing distortion of the glass surface, further comprising a step of performing a blasting process to prevent scratches when removing the distortion on the glass surface before removing the distortion of the glass surface.

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