WO2012133466A1 - Mehod for producing glass plate - Google Patents
Mehod for producing glass plate Download PDFInfo
- Publication number
- WO2012133466A1 WO2012133466A1 PCT/JP2012/058022 JP2012058022W WO2012133466A1 WO 2012133466 A1 WO2012133466 A1 WO 2012133466A1 JP 2012058022 W JP2012058022 W JP 2012058022W WO 2012133466 A1 WO2012133466 A1 WO 2012133466A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- glass
- glass plate
- stirring blade
- molten glass
- bubbles
- Prior art date
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/18—Stirring devices; Homogenisation
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/167—Means for preventing damage to equipment, e.g. by molten glass, hot gases, batches
- C03B5/1672—Use of materials therefor
- C03B5/1675—Platinum group metals
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B18/00—Shaping glass in contact with the surface of a liquid
- C03B18/02—Forming sheets
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/18—Stirring devices; Homogenisation
- C03B5/187—Stirring devices; Homogenisation with moving elements
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
- C03B5/00—Melting in furnaces; Furnaces so far as specially adapted for glass manufacture
- C03B5/16—Special features of the melting process; Auxiliary means specially adapted for glass-melting furnaces
- C03B5/235—Heating the glass
Definitions
- the present invention relates to a method for producing a glass plate.
- the glass plate is used as a glass substrate constituting a thin film transistor driving liquid crystal display device (TFT-LCD), and also as a cover glass covering a display portion.
- TFT-LCD thin film transistor driving liquid crystal display device
- the present invention has been made in view of the above problems, and provides a method for producing a glass plate capable of effectively suppressing bubbles in glass.
- Bubbles with a size of 300 ⁇ m or less are often formed when a new unused platinum or platinum alloy stirring blade (also called a stirrer) is introduced into the production line, and the bubbles are generated after the clarification step.
- a new unused platinum or platinum alloy stirring blade also called a stirrer
- the bubbles formed in the glass include those containing O 2 , N 2 , SO 2 , and CO 2 as components, and bubbles having a size of 300 ⁇ m or less are mainly composed of CO 2.
- the bubbles containing CO 2 as a component are considered to be derived from organic matter, and the organic matter is a residue of what was used in the manufacturing process of the stirring blade such as oil, resin or dust, or external It is thought that the flying material from is attached to the surface of the stirring blade, I found out.
- the inventor of the present invention thought that the formation of bubbles could be effectively suppressed by removing deposits on the surface of the stirring blade made of platinum or platinum alloy that contact the molten glass.
- the present invention has been made from such a viewpoint, and the glass plate manufacturing method according to the present invention performs a heat treatment on a stirring blade made of platinum or a platinum alloy before the glass manufacturing line is put into full operation. This includes a preparation step of removing deposits on the surface of the stirring blade that comes into contact with the molten glass.
- the preparation step includes exposing the stirring blade to a molten glass having a temperature higher by 30 ° C. or more than during actual operation.
- the preparation step includes exposing the stirring blade to molten glass having a viscosity of 120 Pa ⁇ S or less.
- the preparatory step is 50 ° C. or higher than the temperature of the molten glass that contacts the surface of the stirring blade during actual operation in the off-line state where the stirring blade is removed from the glass manufacturing line. It is preferable to include exposure to a highly heated atmosphere.
- the glass plate manufacturing method of the present invention it is possible to effectively suppress the formation of bubbles in the glass.
- the glass plate production method according to the present invention can be applied to the production of any glass plate, particularly for flat panel displays such as liquid crystal display devices and plasma display devices. It is suitable for manufacture of the glass substrate of this, or the cover glass which covers a display part.
- glass raw materials are first prepared so as to have a desired glass composition.
- the raw materials when manufacturing a glass substrate for a flat panel display, it is preferable to prepare the raw materials so as to have the following composition.
- P RO: 5 to 20% by mass (wherein R is at least one selected from Mg, Ca, Sr and Ba),
- said glass for liquid crystal substrates does not contain arsenic and antimony substantially. That is, even if these substances are included, they are as impurities. Specifically, these substances include 0.1% by mass including oxides of As 2 O 3 and Sb 2 O 3. The following is preferable.
- the glasses of the present invention may contain various other oxides to adjust the various physical, melting, fining, and forming characteristics of the glass.
- examples of such other oxides include, but are not limited to, SnO 2 , TiO 2 , MnO, ZnO, Nb 2 O 5 , MoO 3 , Ta 2 O 5 , WO 3 , Y 2 O 3 , and it includes La 2 O 3.
- Nitrate and carbonate can be used as the RO supply source in (p) in the above (a) to (r).
- nitrate as a supply source of RO at a ratio suitable for the process.
- the glass plate manufactured in the present embodiment is manufactured continuously unlike a system in which a certain amount of glass raw material is supplied to a melting furnace and batch processing is performed.
- the glass plate applied in the production method of the present invention may be a glass plate having any thickness and width.
- the glass plate manufacturing method according to an embodiment of the present invention includes a series of steps shown in the flowchart of FIG. 1 and uses the glass plate manufacturing line 100 shown in FIG.
- the glass raw material prepared to have the above composition is first melted in the melting step (step S101).
- the raw material is put into the melting tank 101 and heated to a predetermined temperature.
- the predetermined temperature is preferably 1550 ° C. or higher.
- the heated raw material melts to form molten glass.
- the molten glass is fed into the clarification tank 102 where the next clarification step (step S102) is performed through the first transfer pipe 105a.
- the molten glass is clarified. Specifically, when the molten glass is heated to a predetermined temperature in the clarification tank 102, the gas component contained in the molten glass forms bubbles or vaporizes and escapes out of the molten glass.
- the predetermined temperature is preferably 1610 ° C. or higher.
- the clarified molten glass is sent through the second transfer pipe 105b to the agitation tank 103 where the next step, the homogenization step (step S103), is performed.
- step S103 the molten glass is homogenized.
- FIG. 3 shows the agitation tank 103. Specifically, the molten glass is homogenized in the stirring vessel 103 by being stirred by a stirring blade 103a described later provided in the stirring vessel 103. The molten glass fed into the stirring vessel 103 is heated so as to be in a predetermined temperature range.
- the predetermined temperature range is preferably 1440 ° C. (viscosity: about 121 Pa ⁇ S) to 1500 ° C. (viscosity: about 60 Pa ⁇ S), for example, in the case of a glass substrate for a flat panel display having the above composition.
- the homogenized molten glass is sent from the stirring tank 103 to the third transfer pipe 105c.
- the molten glass is heated in the third transfer pipe 105c so as to have a temperature suitable for molding, and sent to the molding apparatus 104 where the next molding process (step S105) is performed.
- the temperature suitable for molding is preferably about 1200 ° C.
- the molten glass is formed into a plate-like glass.
- the molten glass is continuously formed into a ribbon shape by the overflow downdraw method.
- the formed ribbon-shaped glass is cut into a glass plate.
- the overflow downdraw method is a method known per se. For example, as described in U.S. Pat. No. 3,338,696, the molten glass poured into the molded body and overflowed, It is a method of forming a ribbon-like glass by drawing down the outer surface and flowing down and joining the bottom of the molded body downward.
- the agitation tank 103 is a container that accommodates molten glass made of platinum or a platinum alloy, and includes an agitation blade 103a made of platinum or a platinum alloy.
- a platinum alloy for example, it is preferable to use a platinum-rhodium alloy having components of 90% by mass of platinum and 10% by mass of rhodium.
- a platinum-rhodium-zirconium alloy which is reinforced platinum in which a metal oxide such as zirconium oxide is dispersed in platinum may be used.
- the stirring blade 103a has a rotating shaft and a plurality of blades attached to the rotating shaft.
- the rotating shaft is vertically inserted into the container from the ceiling of the container.
- the plurality of blades are attached to the rotation shaft radially about the rotation shaft.
- the rotating shaft is rotated by a driving unit such as a motor. When the rotating shaft rotates, the plurality of blades attached to the rotating shaft stir the molten glass.
- the unused new device may have deposits on the surface that contacts the molten glass.
- deposits such as dust, resin, and organic substances such as oil that adhere to the surface during the manufacturing process or finishing of the stirring blade 103a. Since it becomes an impurity, it is removed as much as possible by washing.
- the inventors of the present invention while investigating the cause of the formation of very fine bubbles in the glass, there are very fine polishing scratches and irregularities on the surface of the stirring blade 103a that looks visually smooth, It has been newly found that deposits that cannot be completely removed by ordinary cleaning may remain on the scratches and irregularities. In particular, organic substances among the attached substances are highly likely to cause bubbles in the glass.
- the stirring blade 103a when a new unused device such as the stirring blade 103a is introduced into the glass plate production line 100, it is preferable to perform the preparation operation for removing these deposits and then operate the glass plate production line 100 in full operation. .
- the preparation step as described below, the surface of the stirring blade 103a that comes into contact with the molten glass is subjected to a heat treatment to remove deposits on the surface. Specifically, it is preferable to perform either the following offline heat treatment or online heat treatment. Moreover, you may perform both heat processing.
- the stirring blade 103a is heat-treated with the stirring blade 103a installed on the glass plate production line 100 (online). Specifically, it is preferable to expose the surface of the stirring blade 103a in contact with the molten glass to the molten glass by causing the molten glass having a temperature higher than that during the actual operation to flow into the stirring vessel 103 and rotating the stirring blade 103a.
- Molten glass is generated by operating each of the above devices on the glass plate production line 100. That is, the glass raw material is melted in the melting tank 101 in accordance with the above-described glass plate manufacturing process shown in FIG. 1 in the same manner as in the actual operation to produce molten glass, and the molten glass is supplied to the first transfer pipe.
- the molten glass is made to flow in order to 105a, the clarification tank 102, the second transfer pipe 105b, and the stirring tank 103.
- the temperature of the molten glass in contact with the stirring blade 103a is preferably higher than that during the actual operation.
- the temperature of the molten glass is preferably about 30 ° C. or more higher than the temperature in contact with the stirring blade 103a during actual operation.
- the temperature of the molten glass in contact with the stirring blade 103a during the actual operation is about 1440 ° C., it is preferable to flow the molten glass higher than that by 30 ° C., that is, 1470 ° C. or more, to the stirring vessel 103.
- the temperature of the molten glass is too high, the life of the stirring vessel 103 and other devices on the glass plate production line 100 located downstream thereof may be shortened. It is preferable that the temperature is not more than 100 ° C. higher than the operating temperature.
- the viscosity of the molten glass is preferably lower than that during actual operation, and is preferably 120 Pa ⁇ S or less. Molten glass has a lower viscosity as the temperature increases. By exposing the surface of the stirring blade 103a to a molten glass having a low viscosity, that is, smooth, it is possible to expose the deposits remaining on the surface to a high temperature, and by rubbing the molten glass against the surface, fine depressions The adhering matter that has entered can be more reliably washed away, which is preferable. However, if the viscosity of the molten glass is too low, the frictional force against the surface of the stirring blade 103a is too low, and the effect of rubbing off the deposits does not appear.
- the viscosity of the molten glass is preferably 50 Pa ⁇ S or more.
- the agitating blade 103a is heat-treated with the stirring blade 103a removed from the glass plate production line 100 (off-line).
- a stirring blade 103a is placed in a furnace made of refractory metal such as platinum or a platinum alloy in an off-line state, the atmosphere in the furnace is heated, and the surface of the stirring blade 103a in contact with the molten glass is It is preferable to expose to a high temperature atmosphere.
- the atmosphere in the furnace is preferably heated by heating the atmosphere with a gas burner. Furthermore, it is preferable to heat the furnace by energizing the furnace with power supply equipment.
- the temperature of the atmosphere is preferably 50 ° C.
- the temperature of the molten glass touching the stirring blade 103a during actual operation is 1445 ° C
- the temperature is preferably 50 ° C or higher (for example, 1500 ° C).
- the surface of the stirring blade 103a that is in contact with the molten glass is preferably exposed to this high temperature atmosphere for at least 24 hours.
- the heat treatment in the high-temperature atmosphere for the stirring blade 103a described above as the offline heat treatment is not necessarily performed in an offline furnace, but is performed in the stirring tank 103 installed on the glass plate production line 100. May be.
- the above glass plate production line 100 was operated to produce a glass plate.
- the glass raw material, SiO 2 is the composition of the glass plate to be produced: 60.9 wt%, B 2 O 3: 11.6 wt%, Al 2 O 3: 16.9 wt%, MgO: 1.7 mass%, CaO: 5.1 wt%, SrO: 2.6 wt%, BaO: 0.7 wt%, K 2 O: 0.25 wt%, Fe 2 O 3: 0.15 wt%, SnO 2 : Prepared to 0.13 mass%.
- the temperature of the molten glass in contact with the stirring blade 103a was about 1445 ° C. (viscosity about 113 Pa ⁇ S) as in the case of the actual operation of the glass plate production line 100.
- the number of bubbles in the manufactured glass plate was measured, and it was first confirmed that the number of bubbles having a size of 300 ⁇ m or less was about 0.24 in 1 kg of glass.
- the size analyzes the components of the following bubble 300 [mu] m, it was confirmed that component is predominantly CO 2.
- the temperature of the molten glass touching the stirring blade 103a was set to about 1484 ° C. (viscosity about 71 Pa ⁇ S) by 30 ° C. or more higher than about 1445 ° C. during the actual operation of the glass plate production line 100. After this was continued for 3 days, a glass plate was produced, and when the number of bubbles contained in the produced glass plate was measured, the number of bubbles having a size of 300 ⁇ m or less was about 0.16 in 1 kg of glass. It was.
- the above-described glass plate production line 100 shown in FIG. 2 is used according to the above-described series of glass plate production steps shown in the flowchart of FIG. Was operated to produce a glass plate.
- the glass raw material, SiO 2 is the composition of the glass plate to be produced: 60.9 wt%, B 2 O 3: 11.6 wt%, Al 2 O 3: 16.9 wt%, MgO: 1.7 mass%, CaO: 5.1 wt%, SrO: 2.6 wt%, BaO: 0.7 wt%, K 2 O: 0.25 wt%, Fe 2 O 3: 0.15 wt%, SnO 2 : Prepared to 0.13 mass%.
- the temperature of the molten glass in contact with the stirring blade 103a was about 1445 ° C. (viscosity about 113 Pa ⁇ S) as in the case of the actual operation of the glass plate production line 100.
- the number of bubbles in the glass plate produced on the first day was measured, the number of bubbles having a size of 300 ⁇ m or less was about 0.24 in 1 kg of glass.
- the number of bubbles having a size of 300 ⁇ m or less was about 0.35 in 1 kg of glass. .
- the components of bubbles having a size of 300 ⁇ m or less were analyzed, the components were mainly CO 2 .
- the stirring blade 103a is removed from the glass plate production line 100 for producing a glass plate containing bubbles with a size exceeding 300 ⁇ m in size exceeding the allowable range as a product, and the stirring blade 103a is removed.
- the above-described offline heat treatment was performed. Specifically, the stirring blade 103a was placed in an offline platinum alloy furnace, and the furnace was energized by power supply equipment, and the atmosphere in the furnace was heated by an oxygen burner. The stirring blade 103a was placed in the furnace for 24 hours while the temperature of the atmosphere in the furnace was about 1500 ° C.
- the stirring blade 103a was put into the glass plate production line 100 again, and glass plates were continuously produced by the same method using the same raw materials and the glass plate production line 100 as in the conventional example.
- the temperature and viscosity of the molten glass flowing through the glass plate production line 100 were the same as in actual operation. That is, the molten glass touched by the stirring blade 103a had a temperature of about 1445 ° C. and a viscosity of about 113 Pa ⁇ S, as in the actual operation.
- the number of bubbles contained in the produced glass plate was measured, the number of bubbles having a size of 300 ⁇ m or less in 1 kg of glass was about 0.12 in 1 kg of glass.
- the surface of the stirring blade 103a in contact with the molten glass is an atmosphere having a temperature higher by 50 degrees or more than the molten glass in contact with the surface during the actual operation of the glass plate production line 100.
- the glass plate is manufactured after being exposed to at least 24 hours, it can be seen that the number of bubbles of 300 ⁇ m or less contained in the glass plate can be reduced.
- the glass plate manufacturing method according to the present invention includes a surface that contacts the molten glass of the stirring blade 103a by performing a heat treatment on the stirring blade 103a made of platinum or a platinum alloy before the glass plate manufacturing line 100 is fully operated. And a preparatory step for removing the deposits.
- the glass plate is manufactured after heat-treating the surface of the stirring blade 103a made of platinum or platinum alloy that contacts the molten glass.
- bubbles formed in the glass can be effectively suppressed.
- the manufacturing method of the glass plate which concerns on this invention includes exposing a stirring blade 103a to the molten glass of about 30 degreeC or more higher temperature than the time of this operation.
- the surface of the stirring blade 103a made of platinum or platinum alloy that contacts the molten glass is the temperature of the molten glass that contacts the surface when the glass plate production line 100 is in operation 1445. Formation of a glass plate after exposure to molten glass at 1484 ° C., which is 30 ° C. higher than 30 ° C., can effectively suppress the formation of bubbles in the glass.
- the manufacturing method of the glass plate which concerns on this invention includes exposing a stirring blade 103a to the molten glass whose viscosity is 120 Pa * S or less.
- the glass plate is manufactured after the surface of the stirring blade 103a made of platinum or platinum alloy that is in contact with the molten glass is exposed to the molten glass having a viscosity of about 71 Pa ⁇ S. As a result, the formation of bubbles in the glass can be effectively suppressed.
- the glass plate manufacturing method according to the present invention is based on the temperature of the molten glass in contact with the surface of the stirring blade 103a during actual operation in the off-line state in which the preparation step is off the stirring blade 103a from the glass plate manufacturing line 100. It is preferable to include exposure to an atmosphere heated to 50 ° C. or higher.
- the temperature of the molten glass that contacts the molten glass of the stirring blade 103a made of platinum or platinum alloy contacts the surface when the glass plate production line 100 is in operation 1445.
- Modification (5-1) Modification A mixes the raw material suitable for manufacture of the glass substrate for flat panel displays, and manufactures a glass plate using the glass plate manufacturing method concerning this invention.
- the glass plate manufacturing method according to the present invention may be used, for example, to manufacture a glass plate for a cover glass.
- the temperature of the molten glass contacting the surface of the stirring blade 103a may be about 1350 ° C. (viscosity is about 74 Pa ⁇ S). preferable. Therefore, in order to effectively suppress the formation of bubbles, the above-described online heat treatment in which the surface of the stirring blade 103a is exposed to a molten glass having a temperature 30 ° C. higher than the temperature (for example, 1380 ° C. or higher), or It is preferable to manufacture the glass plate after performing the above-described off-line heat treatment in which the surface of the stirring blade 103a is exposed to an atmosphere having a temperature higher than the temperature by 50 ° C. or higher (for example, 1400 ° C. or higher), or both. . In the case of the glass having the above-described composition according to this modification, the viscosity is about 56 Pa ⁇ S at 1380 ° C.
- the present invention has been described in detail by taking as an example the production of a glass plate that suppresses the formation of bubbles due to deposits on the surface of the stirring blade 103a, but the application of the present invention is not limited to this.
- the present invention can be applied to surface deposits that come into contact with molten glass of other glass manufacturing apparatuses such as the first transfer pipe 105a, the second transfer pipe 105b, the third transfer pipe 105c, the clarification pipe 102, and the molding apparatus 104.
- the present invention can also be applied to the production of glass plates that suppress the formation of the resulting bubbles.
Abstract
Description
(i)サイズが300μm以下の気泡は、新しい未使用の白金又は白金合金製の攪拌翼(スターラーともいう)を製造ラインに導入した際に形成されることが多く、気泡は清澄工程の後に発生したものであると考えられること、
(ii)ガラス中に形成される気泡には、O2、N2、SO2、CO2を成分とするものがあり、サイズが300μm以下の気泡は、主にCO2を成分とするものであること、
(iii)CO2を成分とする気泡は、有機物に由来するものであると考えられ、当該有機物は、油、樹脂や塵等の攪拌翼の製造過程において用いられたものの残留物、あるいは、外部からの飛来物が攪拌翼の表面に付着した物と考えられること、
を突き止めた。 The inventor of the present invention has conducted intensive research on a method for suppressing the formation of bubbles in glass,
(I) Bubbles with a size of 300 μm or less are often formed when a new unused platinum or platinum alloy stirring blade (also called a stirrer) is introduced into the production line, and the bubbles are generated after the clarification step. What is considered to be
(Ii) The bubbles formed in the glass include those containing O 2 , N 2 , SO 2 , and CO 2 as components, and bubbles having a size of 300 μm or less are mainly composed of CO 2. There is,
(Iii) The bubbles containing CO 2 as a component are considered to be derived from organic matter, and the organic matter is a residue of what was used in the manufacturing process of the stirring blade such as oil, resin or dust, or external It is thought that the flying material from is attached to the surface of the stirring blade,
I found out.
(1-1)ガラスの原料
本発明に係るガラス板の製造方法は、あらゆるガラス板の製造に適用可能であるが、特に液晶表示装置やプラズマディスプレイ装置などのフラットパネルディスプレイ用のガラス基板、あるいは、表示部を覆うカバーガラスの製造に好適である。 (1) Overall Configuration (1-1) Glass Raw Material The glass plate production method according to the present invention can be applied to the production of any glass plate, particularly for flat panel displays such as liquid crystal display devices and plasma display devices. It is suitable for manufacture of the glass substrate of this, or the cover glass which covers a display part.
(a)SiO2:50~70質量%、
(b)B2O3:5~18質量%、
(c)Al2O3:10~25質量%、
(d)MgO:0~10質量%、
(e)CaO:0~20質量%、
(f)SrO:0~20質量%、
(o)BaO:0~10質量%、
(p)RO:5~20質量%(但し、Rは、Mg、Ca、SrおよびBaから選ばれる少なくとも1種である)、
(q)R’ 2O:0.10質量%を超え2.0質量%以下(但し、R’は、Li、Na、およびKから選ばれる少なくとも1種である)、
(r)酸化スズ、酸化鉄、および、酸化セリウムなどから選ばれる少なくとも1種の金属酸化物を合計で0.05~1.5質量%。 In order to produce a glass plate according to the present invention, glass raw materials are first prepared so as to have a desired glass composition. For example, when manufacturing a glass substrate for a flat panel display, it is preferable to prepare the raw materials so 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 at least one selected from Mg, Ca, Sr and Ba),
(Q) R ′ 2 O: more than 0.10% by mass and 2.0% by mass or less (provided that R ′ is at least one selected from Li, Na, and K),
(R) 0.05 to 1.5 mass% in total of at least one metal oxide selected from tin oxide, iron oxide, cerium oxide, and the like.
本発明の一実施形態に係るガラス板の製造方法は、図1のフローチャートが示す一連の工程を含み、図2が示すガラス板製造ライン100を用いる。 (1-2) Overview of Glass Manufacturing Process The glass plate manufacturing method according to an embodiment of the present invention includes a series of steps shown in the flowchart of FIG. 1 and uses the glass
図3に、攪拌槽103を示す。撹拌槽103は、白金又は白金合金製の溶融ガラスを収容する容器であり、白金又は白金合金製の攪拌翼103aを備える。白金合金の場合、例えば白金90質量%、ロジウム10質量%、の成分を有する白金-ロジウム合金を用いることが好ましい。また、酸化ジルコニウムなどの金属酸化物を白金中に分散させた強化白金である、白金-ロジウム-ジルコニウム合金を用いてもよい。攪拌翼103aは、回転軸と、当該回転軸に取り付けられた複数の翼とを有する。回転軸は、容器の天井部から容器内に垂直に差し込まれている。複数の翼は、回転軸を中心として放射状に回転軸に取り付けられている。回転軸は、モーター等の駆動部により回転される。回転軸が回転すると、回転軸に取り付けられた複数の翼は、溶融ガラスを撹拌する。 (1-3) Stirrer Tank and Stirrer Blade FIG. The
未使用の新しい装置は、溶融ガラスと接触する表面に付着物が付いている可能性がある。付着物は、攪拌翼103aの製造過程又は仕上げの際にその表面に付着する埃や樹脂、油等の有機物など様々なものがあると考えられるが、これらの付着物は、通常、ガラス成分に対する不純物となるため洗浄によって極力除去されている。しかし、本発明の発明者は、ガラス中にごく微細な気泡が形成される原因について調べるうちに、目視においては平滑に見える攪拌翼103aの表面に非常に微細な研磨傷や凹凸が存在し、当該傷や凹凸に通常の洗浄では完全に除去できない付着物が残存していることがあることを新たに見出した。特に、付着物の中でも有機物は、ガラス中の気泡形成の原因となる可能性が高い。つまり、有機物に含まれている炭素が酸素と結合して、二酸化炭素ガスを発生させ、このガスがガラス中に閉じ込められ、気泡を形成すると考えられる。そこで、攪拌翼103a等の新しい未使用の装置をガラス板製造ライン100に投入する際は、これらの付着物を除去する準備工程を行ってから、ガラス板製造ライン100を本稼働させるのが好ましい。準備工程では、以下で説明するとおり攪拌翼103aの溶融ガラスと接触する表面に対して熱処理を行い、当該表面の付着物を除去する。具体的には、次のオフライン熱処理又はオンライン熱処理のいずれかを行なうことが好ましい。また、両方の熱処理を行ってもよい。 (2) Details of preparation process The unused new device may have deposits on the surface that contacts the molten glass. There are various kinds of deposits such as dust, resin, and organic substances such as oil that adhere to the surface during the manufacturing process or finishing of the
オンライン熱処理では、攪拌翼103aがガラス板製造ライン100に設置された状態(オンライン)で、攪拌翼103aに対して熱処理を行なう。具体的には、本稼動時よりも高温の溶融ガラスを攪拌槽103に流して攪拌翼103aを回転させることにより、溶融ガラスと接触する攪拌翼103aの表面を当該溶融ガラスに晒すのが好ましい。溶融ガラスは、ガラス板製造ライン100上の上述の各装置を稼働させて生成する。すなわち、本番稼動時と同じように図1に示された上述のガラス板の製造工程にしたがってガラスの原料を溶解槽101にて溶解して溶融ガラスを生成し、当該溶融ガラスを第1移送管105a、清澄槽102、第2移送管105b、そして、攪拌槽103へと順に溶融ガラスを流す。但し、前述のとおり攪拌翼103aに接する溶融ガラスの温度は、本稼動時よりも高い方が好ましい。好ましくは、溶融ガラスの温度は、本稼動時に攪拌翼103aに接する温度よりも30℃程度以上高いことが好ましい。例えば、本番稼動時に攪拌翼103aに接する溶融ガラスの温度が約1440℃であるとすれば、それよりも30℃以上高い、すなわち、1470℃以上の溶融ガラスを攪拌槽103に流すことが好ましい。但し、溶融ガラスの温度が高すぎると攪拌槽103及びそれより下流に位置するガラス板製造ライン100上の他の装置の寿命を縮めることがあるため、攪拌翼103aに触れる溶融ガラスの温度が本稼動時の温度よりも100℃以上高くないことが好ましい。 (2-1) Online Heat Treatment In the online heat treatment, the
オフライン熱処理では、攪拌翼103aがガラス板製造ライン100から外れた状態(オフライン)で、攪拌翼103aに対して熱処理を行なう。具体的には、オフライン状態の白金又は白金合金等の耐火金属製の炉の中に攪拌翼103aを入れ、当該炉内の雰囲気を加熱して、当該攪拌翼103aの溶融ガラスと接触する表面を高温の雰囲気に晒すのが好ましい。炉内の雰囲気の加熱は、ガスバーナーにより雰囲気を加熱することにより行なうのが好適である。また、さらには、当該炉を電源設備により通電させることにより加熱するのが好適である。雰囲気の温度は、本稼動時に攪拌翼103aが接触する溶融ガラスの温度よりも50℃以上高い温度であることが好ましい。例えば、本稼動時に攪拌翼103aに触れる溶融ガラスの温度が1445℃であれば、それより50℃以上高い温度(例えば、1500℃)であることが好ましい。攪拌翼103aの溶融ガラスと接触する表面をこの高温の雰囲気に少なくとも24時間晒すことが好ましい。 (2-2) Off-line heat treatment In the off-line heat treatment, the agitating
(3-1)オンライン熱処理の実施例
未使用で新品の攪拌翼103aを使用し、図1のフローチャートに示されている上述の一連のガラス板製造工程に従い、図2に示した上述のガラス板製造ライン100を稼動させてガラス板を製造した。なお、ガラス原料は、製造されるガラス板の組成がSiO2:60.9質量%、B2O3:11.6質量%、Al2O3:16.9質量%、MgO:1.7質量%、CaO:5.1質量%、SrO:2.6質量%、BaO:0.7質量%、K2O:0.25質量%、Fe2O3:0.15質量%、SnO2:0.13質量%となるように調合した。攪拌翼103aに触れる溶融ガラスの温度は、ガラス板製造ライン100の本稼動時と同じく約1445℃(粘度約113Pa・S)であった。製造されたガラス板中の気泡の数を計測し、サイズが300μm以下の気泡の数が、1kgのガラス中約0.24個であることを先ず確認した。また、サイズが300μm以下の気泡の成分を分析し、成分が主にCO2であることを確認した。 (3) Examples (3-1) Examples of Online Heat Treatment Using an unused and
未使用で新品の攪拌翼103aを使用し、図1のフローチャートに示されている上述の一連のガラス板製造工程に従い、図2に示した上述のガラス板製造ライン100を稼動させてガラス板を製造した。なお、ガラス原料は、製造されるガラス板の組成がSiO2:60.9質量%、B2O3:11.6質量%、Al2O3:16.9質量%、MgO:1.7質量%、CaO:5.1質量%、SrO:2.6質量%、BaO:0.7質量%、K2O:0.25質量%、Fe2O3:0.15質量%、SnO2:0.13質量%となるように調合した。攪拌翼103aに触れる溶融ガラスの温度は、ガラス板製造ライン100の本稼動時と同じく約1445℃(粘度約113Pa・S)であった。1日目に製造されたガラス板中の気泡の数を計測すると、サイズが300μm以下の気泡の数は、1kgのガラス中約0.24個であった。さらに20日間ガラス板の製造を続け、21日目に製造されたガラス板中の気泡の数を計測すると、サイズが300μm以下の気泡の数は、1kgのガラス中約0.35個であった。なお、サイズが300μm以下の気泡の成分を分析したところ、成分は主にCO2であった。 (3-2) Comparative Example The above-described glass
製品としての許容範囲を超える数のサイズが300μm以下の気泡を含むガラス板を製造したガラス板製造ライン100から攪拌翼103aを外し、当該攪拌翼103aに対して上述のオフライン熱処理を行った。具体的には、オフラインの白金合金製の炉の中に攪拌翼103aを入れ、炉を電源設備により通電させるとともに、炉内の雰囲気を酸素バーナーにより加熱した。炉内の雰囲気の温度が約1500℃の状態で攪拌翼103aを24時間炉内に入れておいた。その後、攪拌翼103aをガラス板製造ライン100に再び投入し、上記従来例と同じ原料及びガラス板製造ライン100を用いて同じ方法でガラス板を連続して製造した。ガラス板製造ライン100に流す溶融ガラスの温度及び粘度は、本稼動時と同じにした。すなわち、攪拌翼103aが触れる溶融ガラスは、本稼動時と同じく、温度が約1445℃、粘度が約113Pa・Sであった。製造されたガラス板が含む気泡の数を計測すると、1kgのガラス中のサイズが300μm以下の気泡の個数は、1kgのガラス中約0.12個であった。 (3-3) Example of off-line heat treatment The
(4-1)
本発明に係るガラス板の製造方法は、ガラス板製造ライン100を本稼働させる前に、白金又は白金合金製の攪拌翼103aに対して熱処理を行なうことにより攪拌翼103aの溶融ガラスと接触する表面の付着物を取り除く準備工程を含むことを特徴とする。 (4) Features (4-1)
The glass plate manufacturing method according to the present invention includes a surface that contacts the molten glass of the
また、本発明に係るガラス板の製造方法は、準備工程が、攪拌翼103aを本稼動時よりも30℃程度以上高い温度の溶融ガラスに晒すことを含むことが好ましい。 (4-2)
Moreover, it is preferable that the manufacturing method of the glass plate which concerns on this invention includes exposing a
また、本発明に係るガラス板の製造方法は、準備工程が、攪拌翼103aを粘度が120Pa・S以下の溶融ガラスに晒すことを含むことが好ましい。 (4-3)
Moreover, it is preferable that the manufacturing method of the glass plate which concerns on this invention includes exposing a
また、本発明に係るガラス板の製造方法は、準備工程が、攪拌翼103aをガラス板製造ライン100から外れたオフラインの状態において、本稼動時に攪拌翼103aの表面に接触する溶融ガラスの温度よりも50℃以上高く加熱された雰囲気に晒すことを含むことが好ましい。 (4-4)
Further, the glass plate manufacturing method according to the present invention is based on the temperature of the molten glass in contact with the surface of the
(5-1)変形例A
上記実施形態は、フラットパネルディスプレイ用のガラス基板の製造に好適な原料を調合し、本発明にかかるガラス板製造方法を用いてガラス板を製造するものである。しかし、他の実施形態においては、本発明にかかるガラス板製造方法を、例えば、カバーガラス用のガラス板を製造するのに用いてもよい。この場合、Na2O、K2O、あるいは、Li2Oとして表されるアルカリ金属酸化物の濃度の合計が2.0質量%より大きい組成を有するようにガラス原料を調合するのが好適である。 (5) Modification (5-1) Modification A
The said embodiment mixes the raw material suitable for manufacture of the glass substrate for flat panel displays, and manufactures a glass plate using the glass plate manufacturing method concerning this invention. However, in other embodiments, the glass plate manufacturing method according to the present invention may be used, for example, to manufacture a glass plate for a cover glass. In this case, it is preferable to prepare the glass raw material so that the total concentration of alkali metal oxides expressed as Na 2 O, K 2 O, or Li 2 O has a composition larger than 2.0 mass%. is there.
101 溶解槽
102 清澄槽
103 撹拌槽
103a 攪拌翼
104 成形装置 DESCRIPTION OF
Claims (4)
- ガラス製造ラインを本稼働させる前に、白金又は白金合金製の攪拌翼に対して熱処理を行なうことにより前記攪拌翼の溶融ガラスと接触する表面の付着物を取り除く準備工程、
を含むことを特徴とする、
ガラス板の製造方法。 Prior to full operation of the glass production line, a preparatory step of removing deposits on the surface of the stirring blade that comes into contact with the molten glass by performing a heat treatment on the stirring blade made of platinum or platinum alloy,
Including,
Manufacturing method of glass plate. - 前記準備工程は、前記攪拌翼を本稼動時よりも30℃以上高い温度の前記溶融ガラスに晒すことを含むことを特徴とする、
請求項1に記載のガラス板の製造方法。 The preparatory step includes exposing the stirring blade to the molten glass having a temperature higher by 30 ° C. or more than during actual operation,
The manufacturing method of the glass plate of Claim 1. - 前記準備工程は、前記攪拌翼を粘度が120Pa・S以下の溶融ガラスに晒すことを含むことを特徴とする、
請求項1又は2に記載のガラス板の製造方法。 The preparatory step includes exposing the stirring blade to a molten glass having a viscosity of 120 Pa · S or less,
The manufacturing method of the glass plate of Claim 1 or 2. - 前記準備工程は、前記攪拌翼を前記ガラス製造ラインから外れたオフラインの状態において、本稼動時に前記攪拌翼の表面に接触する前記溶融ガラスの温度よりも50℃以上高く加熱された雰囲気に晒すことを含むことを特徴とする、
請求項1~3のいずれかに記載のガラス板の製造方法。 In the preparatory step, the stirring blade is exposed to an atmosphere heated at 50 ° C. or more higher than the temperature of the molten glass in contact with the surface of the stirring blade during actual operation in an off-line state off the glass production line. Including,
The method for producing a glass plate according to any one of claims 1 to 3.
Priority Applications (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201280001088.8A CN102933510B (en) | 2011-03-31 | 2012-03-27 | Mehod for producing glass plate |
KR1020127010829A KR101305744B1 (en) | 2011-03-31 | 2012-03-27 | Method for producing glass sheet |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2011081269A JP5265726B2 (en) | 2011-03-31 | 2011-03-31 | Manufacturing method of glass plate |
JP2011-081269 | 2011-03-31 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2012133466A1 true WO2012133466A1 (en) | 2012-10-04 |
Family
ID=46931178
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2012/058022 WO2012133466A1 (en) | 2011-03-31 | 2012-03-27 | Mehod for producing glass plate |
Country Status (5)
Country | Link |
---|---|
JP (1) | JP5265726B2 (en) |
KR (1) | KR101305744B1 (en) |
CN (1) | CN102933510B (en) |
TW (1) | TWI480250B (en) |
WO (1) | WO2012133466A1 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN108395074A (en) * | 2018-04-10 | 2018-08-14 | 湖北新华光信息材料有限公司 | A kind of glass stock crucible and stock method |
JP2021075410A (en) * | 2019-11-06 | 2021-05-20 | 日本電気硝子株式会社 | Glass plate and method for manufacturing glass plate |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0384394A (en) * | 1989-08-25 | 1991-04-09 | Ishikawajima Harima Heavy Ind Co Ltd | Stirring method in melting furnace |
JP2010100462A (en) * | 2008-10-22 | 2010-05-06 | Avanstrate Inc | Agitating blade and agitating device for molten glass |
JP2012046415A (en) * | 2010-08-30 | 2012-03-08 | Corning Inc | Method for eliminating carbon contamination of platinum-containing components for glass making apparatus |
JP2012046414A (en) * | 2010-08-30 | 2012-03-08 | Corning Inc | Method for eliminating carbon contamination of precious metal components |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4440704C2 (en) * | 1994-11-15 | 1997-02-13 | Ilmenau Tech Glas | Stirrer for molten glass |
US7032412B2 (en) * | 2003-03-13 | 2006-04-25 | Corning Incorporated | Methods of manufacturing glass sheets with reduced blisters |
DE102004015577B4 (en) * | 2004-03-30 | 2012-08-23 | Schott Ag | Process for producing glass while avoiding bubbles on precious metal components |
-
2011
- 2011-03-31 JP JP2011081269A patent/JP5265726B2/en active Active
-
2012
- 2012-03-27 KR KR1020127010829A patent/KR101305744B1/en active IP Right Grant
- 2012-03-27 CN CN201280001088.8A patent/CN102933510B/en active Active
- 2012-03-27 WO PCT/JP2012/058022 patent/WO2012133466A1/en active Application Filing
- 2012-03-30 TW TW101111535A patent/TWI480250B/en active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0384394A (en) * | 1989-08-25 | 1991-04-09 | Ishikawajima Harima Heavy Ind Co Ltd | Stirring method in melting furnace |
JP2010100462A (en) * | 2008-10-22 | 2010-05-06 | Avanstrate Inc | Agitating blade and agitating device for molten glass |
JP2012046415A (en) * | 2010-08-30 | 2012-03-08 | Corning Inc | Method for eliminating carbon contamination of platinum-containing components for glass making apparatus |
JP2012046414A (en) * | 2010-08-30 | 2012-03-08 | Corning Inc | Method for eliminating carbon contamination of precious metal components |
Also Published As
Publication number | Publication date |
---|---|
KR20120132673A (en) | 2012-12-07 |
CN102933510A (en) | 2013-02-13 |
JP2012214341A (en) | 2012-11-08 |
TWI480250B (en) | 2015-04-11 |
CN102933510B (en) | 2015-05-06 |
TW201249764A (en) | 2012-12-16 |
JP5265726B2 (en) | 2013-08-14 |
KR101305744B1 (en) | 2013-09-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP5752647B2 (en) | Manufacturing method of glass substrate | |
TWI504574B (en) | Glass plate manufacturing method | |
JP5616450B2 (en) | Manufacturing method of glass plate | |
KR101486133B1 (en) | Method and apparatus for making glass sheet | |
JP6236058B2 (en) | Method for reducing zirconia defects in glass plates | |
TWI570082B (en) | High volume production of display quality glass sheets having low zirconia levels | |
WO2012132471A1 (en) | Glass sheet production method | |
WO2012132474A1 (en) | Glass substrate production method | |
WO2013054532A1 (en) | Method for manufacturing glass plate | |
JP2014009126A (en) | Glass substrate manufacturing method and manufacturing device | |
KR101178027B1 (en) | Production method of glass substrate for liquid crystal display | |
JP5265726B2 (en) | Manufacturing method of glass plate | |
JP6110448B2 (en) | Manufacturing method of glass substrate and stirring device | |
TWI596067B (en) | Manufacturing method of a glass substrate, and manufacturing apparatus of a glass substrate | |
JP5946206B2 (en) | Glass substrate manufacturing method, glass substrate manufacturing apparatus, and stirring apparatus | |
JP2018002539A (en) | Method of manufacturing glass substrate and glass substrate manufacturing apparatus | |
JP2016069217A (en) | Manufacturing method of glass substrate for display, manufacturing apparatus of glass substrate for display, molten glass stirring vessel, molten glass stirrer, and stirring method of molten glass | |
JP5293195B2 (en) | Clarification method of alkali-free glass | |
JP2015124107A (en) | Manufacturing method of glass plate, and agitator | |
CN114641457A (en) | Glass plate and method for manufacturing glass plate | |
TWI388520B (en) | Fining of boroalumino silicate glasses | |
JP2016033099A (en) | Method for manufacturing glass plate, and agitator | |
JP2001328820A (en) | Method for producing glass | |
JP2013001608A (en) | Production apparatus of glass, and method for producing glass using the same | |
JP2014047102A (en) | Manufacturing method for glass substrate, manufacturing device for glass substrate, and agitation tank |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201280001088.8 Country of ref document: CN |
|
ENP | Entry into the national phase |
Ref document number: 20127010829 Country of ref document: KR Kind code of ref document: A |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 12763363 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 12763363 Country of ref document: EP Kind code of ref document: A1 |