WO2023149311A1

WO2023149311A1 - Glass manufacturing apparatus, and glass manufacturing method

Info

Publication number: WO2023149311A1
Application number: PCT/JP2023/002291
Authority: WO
Inventors: 義豊大村; 美穂八木澤; 史朗谷井
Original assignee: Ａｇｃ株式会社
Priority date: 2022-02-01
Filing date: 2023-01-25
Publication date: 2023-08-10
Also published as: CN118574792A; JPWO2023149311A1

Abstract

This glass manufacturing apparatus comprises a melting device for melting a glass raw material to obtain molten glass, a molding device for molding the molten glass into a glass article, and a slow cooling device for slowly cooling the glass article. At least one among the melting device, the molding device, and the slow cooling device includes a heat insulating material containing an inorganic fiber. The inorganic fiber comprises Al₂O₃ and SiO₂, wherein the Al₂O₃ content in the inorganic fiber is at least 60 mass%, and the SiO₂ content in the inorganic fibers is at most 40 mass%.

Description

Glass manufacturing apparatus and glass manufacturing method

The present disclosure relates to a glass manufacturing apparatus and a glass manufacturing method.

The float glass manufacturing apparatus described in Patent Document 1 includes a melting device that melts frit to form molten glass, a molding device that forms the molten glass supplied from the melting device into a strip shape to form a glass ribbon, and a molding device that forms a glass ribbon. a slow cooling device for slowly cooling the glass ribbon formed by the device.

Japanese Patent Application Laid-Open No. 2016-26978

The melting device, molding device, and slow cooling device include heat insulating materials. When the heat insulating material contains inorganic fibers, dust generation from the heat insulating material sometimes deteriorates the quality of the glass.

One aspect of the present disclosure provides a technique for suppressing dust generation from heat insulating materials containing inorganic fibers.

A glass manufacturing apparatus according to an aspect of the present disclosure includes a melting apparatus that obtains molten glass by melting frit, a forming apparatus that forms the molten glass into a glass article, and a slow cooling apparatus that slowly cools the glass article. And prepare. At least one of the melting device, the molding device, and the slow cooling device includes a heat insulating material containing inorganic fibers. The inorganic fibers contain Al ₂ O ₃ and SiO ₂ , the Al ₂ O ₃ content of the inorganic fibers is 60% by mass or more, and the SiO ₂ content of the inorganic fibers is 40% by mass or less.

According to one aspect of the present disclosure, the Al ₂ O ₃ content of the inorganic fibers is 60% by mass or more, so that changes in the crystal structure of the inorganic fibers due to temperature changes can be suppressed, and dust generation from the inorganic fibers can be suppressed. can be suppressed.

FIG. 1 is a cross-sectional view showing a glass manufacturing apparatus according to one embodiment. FIG. 2 is a cross-sectional view showing a specific example of the glass manufacturing apparatus of FIG. 3 is a cross-sectional view showing an example of the upstream end of the molding apparatus of FIG. 2; FIG. 4 is a cross-sectional view showing an example of one end in the width direction of the molding apparatus of FIG. 2. FIG. 5 is a cross-sectional view showing an example of one end in the width direction of the slow cooling device of FIG. 2. FIG. 6 is a cross-sectional view showing an example of the upper structure of the molding apparatus of FIG. 2. FIG. 7 is a cross-sectional view showing an example of a buffer film forming portion of the slow cooling apparatus of FIG. 2. FIG. 8 is a diagram showing an X-ray diffraction spectrum of the heat insulating material of Example 1. FIG. 9 is a diagram showing an X-ray diffraction spectrum of the heat insulating material of Example 2. FIG. FIG. 10 is a diagram showing the dust scattering rates of the heat insulating materials of Examples 1 and 2. FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In addition, in each drawing, the same reference numerals are given to the same or corresponding configurations, and explanations thereof may be omitted. In each drawing, the X-axis direction, Y-axis direction and Z-axis direction are perpendicular to each other, the X-axis direction and Y-axis direction are horizontal directions, and the Z-axis direction is vertical direction. When the glass manufacturing apparatus 1 manufactures plate glass by the float method, the X-axis direction is the glass ribbon conveying direction, and the Y-axis direction is the width direction of the glass ribbon. In the specification, "-" indicating a numerical range means that the numerical values described before and after it are included as lower and upper limits.

First, a glass manufacturing apparatus 1 according to one embodiment will be described with reference to FIG. A glass manufacturing apparatus 1 includes a melting device 2 , a forming device 3 , a slow cooling device 4 and a processing device 5 . The glass manufacturing apparatus 1 may be provided with the melting device 2, the molding device 3, and the slow cooling device 4, and may not be provided with the processing device 5.

The melting device 2 melts frit to produce molten glass. Glass raw materials are prepared by mixing multiple types of materials. The frit may include glass cullet to recycle the glass. The glass raw material may be a powder raw material, or may be a granulated raw material obtained by granulating the powder raw material.

The molding device 3 molds the molten glass obtained in the melting device 2 into glass articles of desired shape. A float method, a fusion method, a roll-out method, or the like is used as a molding method for obtaining a plate-shaped glass article. A plate-shaped glass article is generally called a glass ribbon. A bellows method, a Danner method, or the like is used as a molding method for obtaining a tubular glass article.

The slow cooling device 4 slowly cools the glass article molded by the molding device 3. The slow cooling device 4 has, for example, a heat treatment furnace and transport rollers for transporting the glass article in a desired direction inside the heat treatment furnace. A plurality of conveying rollers are arranged, for example, at intervals in the horizontal direction. The glass article is slowly cooled while being conveyed from the inlet of the heat treatment furnace to the outlet of the heat treatment furnace. If the glass article is slowly cooled, a glass article with less residual strain can be obtained.

The processing device 5 processes the glass article slowly cooled by the slow cooling device 4 into a desired shape. The processing device 5 includes one or more selected from, for example, a cutting device, a grinding device, a polishing device, and a coating device. The cutting device cuts the glass annealed by the annealer 4 . For example, the cutting device forms scribe lines in the glass slowly cooled by the slow cooling device 4 and cuts the glass along the scribe lines. Scribe lines are formed using a cutter or laser beam. The grinding device grinds the glass that has been annealed by the annealer 4 . The polishing device polishes the glass slowly cooled by the slow cooling device 4 . The coating device forms a desired film on the glass annealed by the annealer 4 .

Although not shown, the glass manufacturing apparatus 1 may further have a clarifier. The clarifier removes air bubbles contained in the molten glass before forming the molten glass obtained by the melting device 2 by the forming device 3 . As a method for removing air bubbles, for example, one or more selected from a method of reducing the pressure of the surrounding atmosphere of the molten glass and a method of heating the molten glass to a high temperature is used. The clarification device may be part of the dissolution device 2 .

Next, a specific example of the glass manufacturing apparatus 1 will be described with reference to FIG. The glass manufacturing apparatus 1 of FIG. 2 manufactures plate glass by the float method. Plate glass is, for example, non-alkali glass, aluminosilicate glass, borosilicate glass, soda lime glass, or the like. Alkali-free glass means glass that does not substantially contain alkali metal oxides such as Na ₂ O and K ₂ O. Here, "substantially free of alkali metal oxides" means that the total content of alkali metal oxides is 0.1% by mass or less.

The use of the plate glass is not particularly limited, but for example, it is cover glass for displays (eg, liquid crystal displays, organic EL displays, etc.). If the application of sheet glass is cover glass, the sheet glass is glass for chemical strengthening. Unlike non-alkali glass, glass for chemical strengthening contains alkali metal oxides.

The thickness of the plate glass is selected according to the application of the plate glass. When the glass sheet is used as a cover glass for displays, the thickness of the glass sheet is, for example, 0.1 mm to 5.0 mm. When the glass plate is used as a glass substrate for displays, the thickness of the glass plate is, for example, 0.1 mm to 0.7 mm. When the sheet glass is used for automobiles, the thickness of sheet glass for laminated glass is, for example, 0.5 mm to 6.0 mm, and the thickness of sheet glass for tempered glass is, for example, 2.3 mm to 6.0 mm. When the application of the plate glass is architectural glass, the thickness of the plate glass for double glazing is, for example, 3 mm to 12 mm, the thickness of the plate glass for heat reflecting glass or heat absorbing glass is, for example, 5 mm to 12 mm, and the thickness of the plate glass for tempered glass is 5 mm to 12 mm. The thickness is, for example, 4 mm to 19 mm. The thickness of plate glass for disaster prevention and crime prevention glass is, for example, 3 mm to 5 mm. The thickness of plate glass for fireproof and fireproof glass is, for example, 5 mm to 12 mm. The thickness of plate glass for soundproof glass is, for example, 3 mm to 8 mm. The thickness of plate glass for glass is, for example, 3 mm to 10 mm, the thickness of plate glass for design glass is, for example, 2 mm to 6 mm, the thickness of plate glass for figured glass is, for example, 4 mm to 6 mm, and the thickness of plate glass for ground glass is, for example, 2 mm to 5 mm. is. Double glazing includes those with Low-E films. Disaster prevention and crime prevention glass is laminated glass in which an interlayer is sandwiched between two sheets of glass and press-bonded. Figured glass is glass with a pattern on one side of the glass by the roll-out manufacturing method.

The melting apparatus 2 includes a melting tank 21 containing molten glass G and a burner 22 forming a flame above the molten glass G contained in the melting tank 21 . The glass raw material charged into the melting tank 21 is gradually melted into the molten glass G by radiant heat from the flame formed by the burner 22 . Molten glass G is continuously conveyed from the melting device 2 to the forming device 3 . The heating source is not limited to the burner 22, and may be an electric heater, an electrode, or the like. The electrodes cause the molten glass G to generate heat by applying an electric current to the molten glass G.

The molding device 3 includes a molding furnace 31 that is a heat treatment furnace. The molding furnace 31 has a bath 311 . The bath 311 contains the molten metal M. As the molten metal M, for example, molten tin is used. In addition to molten tin, molten tin alloys and the like can also be used, and the molten metal M should have a higher density than the molten glass G. The molten glass G is continuously supplied onto the molten metal M, and is formed into a strip-shaped glass ribbon GR using the smooth liquid surface of the molten metal M.

The molding furnace 31 has a ceiling 312 above the bathtub 311 . The interior of the molding furnace 31 is filled with a reducing gas to prevent the molten metal M from being oxidized, and is maintained at a pressure higher than the atmospheric pressure. The reducing gas is, for example, a mixed gas of nitrogen gas and hydrogen gas, containing 85% to 98.5% by volume of nitrogen gas and 1.5% to 15% by volume of hydrogen gas. The reducing gas is supplied from the joints between the bricks of the ceiling 312 and the holes in the ceiling 312 .

The molding device 3 includes a heater 32 that heats the glass ribbon GR. The heater 32 is suspended, for example, from the ceiling 312 of the molding furnace 31 and heats the glass ribbon GR passing below. The heater 32 is, for example, an electric heater, and is electrically heated. A plurality of heaters 32 are arranged in a matrix in the conveying direction and the width direction of the glass ribbon GR. By controlling the outputs of the plurality of heaters 32, the temperature distribution of the glass ribbon GR can be controlled, and the plate thickness distribution of the glass ribbon GR can be controlled.

The slow cooling device 4 includes a dross box 41 that is a heat treatment furnace and lift out rolls 42 . The lift out roll 42 is arranged inside the dross box 41 and pulls up the glass ribbon GR from the molten metal M. A plurality of lift out rolls 42 are arranged at intervals in the conveying direction (X-axis direction) of the glass ribbon GR. The number of lift out rolls 42 is not particularly limited. The lift out roll 42 is rotationally driven by a driving device such as a motor (not shown), and conveys the glass ribbon GR obliquely upward by its driving force. The axial direction of the lift out roll 42 is the same direction as the width direction (Y-axis direction) of the glass ribbon GR.

The slow cooling device 4 may include a heater (not shown) on the ceiling of the dross box 41 to adjust the temperature of the glass ribbon GR. The heater may be provided not only above the glass ribbon GR but also below it. Inside the dross box 41, the temperature of the glass ribbon GR is preferably (Tg−50)° C. to (Tg+30)° C. with reference to the glass transition point Tg of the glass ribbon GR.

The slow cooling device 4 includes a slow cooling furnace 45 that is a heat treatment furnace and layer rolls 46 . The slow cooling furnace 45 is arranged downstream of the dross box 41 . The layer roll 46 is arranged inside the annealing furnace 45 and conveys the glass ribbon GR in the longitudinal direction (X-axis direction) of the glass ribbon GR. A plurality of layer rolls 46 are provided at intervals in the conveying direction of the glass ribbon GR. The number of layer rolls 46 is not particularly limited. The layer roll 46 is rotationally driven by a driving device such as a motor (not shown), and the driving force conveys the glass ribbon GR in the horizontal direction (X-axis direction). The axial direction of the layer roll 46 is the same as the width direction (Y-axis direction) of the glass ribbon GR.

The slow cooling device 4 slowly cools the glass ribbon GR to a temperature below the strain point of the glass while conveying the glass ribbon GR with the layer rolls 46 . The slow cooling device 4 may include a heater (not shown) inside the slow cooling furnace 45 to adjust the temperature of the glass ribbon GR.

Next, an example of the upstream end of the molding device 3 in FIG. 2 will be described with reference to FIG. The molding device 3 comprises a spout lip 33 and a twill 34 . Spout lip 33 continuously feeds molten glass G onto molten metal M in bath 311 . The tweel 34 is vertically movable with respect to the spout lip 33 and adjusts the flow rate of the molten glass G flowing over the spout lip 33 . As the distance between the tweel 34 and the spout lip 33 becomes narrower, the flow rate of the molten glass G flowing over the spout lip 33 decreases. The twill 34 is constructed of refractory material. A protective film may be formed on the tweel 34 to prevent contact between the tweel 34 and the molten glass G. FIG. The protective film is made of platinum or a platinum alloy, for example.

The molding furnace 31 has a ceiling 312 above the spout lip 33. The ceiling 312 includes a plurality of horizontally arranged bricks 313 and a heat insulating material 314 placed on the plurality of bricks 313 . A gap is formed between the brick 313 and the twill 34, and a gap is also formed between adjacent bricks 313.例文帳に追加Through these gaps, the heat insulator 314 is exposed to the atmosphere to which the molten glass G is exposed. The heat insulating material 314 is arranged above the molten glass G. As shown in FIG.

The heat insulating material 314 suppresses heat transfer from the inside of the molding furnace 31 to the outside, and keeps the inside of the molding furnace 31 at a high temperature. The thermal conductivity of the heat insulating material 314 is, for example, 1 W/m·K or less, preferably 0.5 W/m·K or less, more preferably 0.3 W/m·K or less, and still more preferably 0. .1 W/m·K or less, and particularly preferably 0.05 W/m·K or less. The thermal conductivity of the heat insulating material 314 is 0 W/m·K or higher.

The heat insulating material 314 contains inorganic fibers. The heat insulating material 314 may be a plate-like board in which a plurality of inorganic fibers are bound together with a binder, or may be a blanket in which a plurality of inorganic fibers are entwined and cotton-like wool is formed into layers. It should be noted that the heat insulating material 314 may be left in a cotton-like state, or may be processed into a cord-like shape. The bubble content of the heat insulating material 314 is, for example, 20% to 95% by volume, preferably 35% to 95% by volume, more preferably 40% to 95% by volume. The upper limit of the numerical range of the bubble content may be 90% by volume.

The inorganic fibers contained in the heat insulating material 314 may be either artificial fibers or natural fibers, and may be crystalline or amorphous. Inorganic fibers include Al ₂ O ₃ and SiO ₂ . Inorganic fibers include, for example, Al ₂ O ₃ and SiO ₂ as a solid solution. The inorganic fibers may contain components other than _Al2O3 and _SiO2 _. Components other than Al ₂ O ₃ and SiO ₂ are, for example, one or more selected from TiO ₂ and Fe ₂ O ₃ . The total content of components other than Al ₂ O ₃ and SiO ₂ is, for example, 3% by mass or less. The chemical composition of inorganic fibers is measured, for example, by X-ray fluorescence spectroscopy (XRF).

The inorganic fibers contained in the heat insulating material 314 have an Al ₂ O ₃ content of 60% by mass or more and an SiO ₂ content of 40% by mass or less. Details will be described in the section of Examples, but if the Al ₂ O ₃ content is 60% by mass or more, changes in the crystal structure of the inorganic fibers due to temperature changes can be suppressed, and dust generation can be suppressed. The inorganic fibers contained in the heat insulating material 314 preferably have an Al ₂ O ₃ content of 90% by mass or less and an SiO ₂ content of 10% by mass or more.

The heat insulating material 314 may be exposed to the atmosphere to which the molten glass G is exposed, as described above. That is, the heat insulating material 314 may be exposed to the molten glass G, and a path from the heat insulating material 314 to the molten glass G (a space continuously connecting from the heat insulating material 314 to the molten glass G) may exist. . According to the present embodiment, generation of dust can be suppressed, so even if there is a path from the heat insulating material 314 to the molten glass G, the amount of dust passing through that path is small and the amount of dust adhering is small.

The molten glass G may have an upward (including obliquely upward) surface, and the heat insulating material 314 may be arranged above the upward surface. Dust tends to fall due to gravity, and the upward surface of molten glass G tends to catch dust. Therefore, the effect of suppressing the generation of dust from the heat insulating material 314 is remarkably obtained. The heat insulating material 314 is preferably arranged directly above the molten glass G, but may be arranged diagonally above.

Note that the technology of the present disclosure can be applied to other than the heat insulating material 314 of the ceiling 312. Any heat insulating material may be used as long as it is used in at least one of the melting device 2 , the molding device 3 and the slow cooling device 4 . The heat insulator may be exposed to the atmosphere to which the glass ribbon GR is exposed. The glass ribbon GR may have an upward surface, and the heat insulating material may be arranged above the surface. The heat insulating material is preferably arranged directly above the glass ribbon GR, but may be arranged diagonally above.

Next, an example of one end in the width direction of the molding device 3 in FIG. 2 will be described with reference to FIG. Forming furnace 31 has a side wall 315 between bath 311 and ceiling 312 . The side wall 315 includes a plurality of vertically aligned bricks 316 and a sealing member 317 that seals the gap between the bottom brick 316 and the bathtub 311 .

The sealing member 317 has, for example, a metal box 318 and a heat insulating material 319 filled inside the box 318 . The box 318 is composed of a plurality of metal plates (not shown). A gap may exist between the plurality of metal plates, and the heat insulating material 319 may be exposed to the atmosphere to which the glass ribbon GR is exposed through the gap.

Heat insulating material 319 includes inorganic fibers, similar to heat insulating material 314 (see FIG. 3). The inorganic fibers contained in the heat insulating material 319 have an Al ₂ O ₃ content of 60% by mass or more and an SiO ₂ content of 40% by mass or less. If the Al ₂ O ₃ content is 60% by mass or more, it is possible to suppress changes in the crystal structure of the inorganic fibers due to temperature changes, and to suppress generation of dust.

The heat insulating material 319 may be exposed to the atmosphere to which the glass ribbon GR is exposed. That is, the heat insulating material 319 may be exposed to the glass ribbon GR, and there may be a path from the heat insulating material 319 to the glass ribbon GR (a space continuously connecting from the heat insulating material 319 to the molten glass G). . According to the present embodiment, generation of dust can be suppressed. Therefore, even if there is a path from the heat insulating material 319 to the glass ribbon GR, the amount of dust passing through that path is small and the amount of dust adhering is small.

The glass ribbon GR may have an upward (including diagonally upward) surface, and the heat insulating material 319 may be arranged above the surface. Dust tends to fall due to gravity, and the upward surface of the glass ribbon GR tends to catch the dust. Therefore, the effect of suppressing the generation of dust from the heat insulating material 319 can be obtained remarkably. The heat insulating material 319 is preferably arranged directly above the glass ribbon GR, but may be arranged diagonally above.

Although not shown, there may be gaps between the plurality of bricks 316 forming the side wall 315, and the heat insulating material 319 may be exposed to the atmosphere to which the glass ribbon GR is exposed through the gaps. Further, there may be gaps between the plurality of bricks forming the ceiling 312, and the heat insulating material 319 may be exposed to the atmosphere to which the glass ribbon GR is exposed through the gaps.

Next, an example of one end in the width direction of the slow cooling device 4 in FIG. 2 will be described with reference to FIG. The annealing furnace 45 has a ceiling 451 , a lower wall 452 and side walls 453 . At least one of the ceiling 451 , the lower wall 452 and the side walls 453 may include, for example, a metal box 454 and a heat insulating material 455 filled inside the box 454 . The box 454 is composed of a plurality of metal plates (not shown). A gap may exist between the plurality of metal plates, and the heat insulating material 455 may be exposed to the atmosphere to which the glass ribbon GR is exposed through the gap.

The side wall 453 has an opening 456 through which the rotating shaft 47 of the layer roll 46 is inserted, and the opening 456 may have a heat insulating material 457 that suppresses the outflow of heat. A driving device for rotating the rotating shaft 47 is arranged outside the slow cooling furnace 45 . By arranging the driving device outside the slow cooling furnace 45, thermal deterioration of the driving device can be suppressed. The heat insulator 457 may be exposed to the atmosphere to which the glass ribbon GR is exposed at the opening 456 .

Heat insulating

materials

455 and 457 include inorganic fibers, similar to heat insulating material 314 (see FIG. 3). The inorganic fibers contained in the

heat insulating materials

455 and 457 have an Al ₂ O ₃ content of 60% by mass or more and an SiO ₂ content of 40% by mass or less. Details will be described in the section of Examples, but if the Al ₂ O ₃ content is 60% by mass or more, changes in the crystal structure of the inorganic fibers due to temperature changes can be suppressed, and dust generation can be suppressed.

The

heat insulating materials

455 and 457 may be exposed to the atmosphere to which the glass ribbon GR is exposed. In other words, the

heat insulating materials

455 and 457 may be exposed to the glass ribbon GR, and the path from the

heat insulating materials

455 and 457 to the glass ribbon GR (the space continuously connecting from the

heat insulating materials

455 and 457 to the glass ribbon GR). may exist. According to the present embodiment, generation of dust can be suppressed. Therefore, even if there is a path from the

heat insulating materials

455 and 457 to the glass ribbon GR, the amount of dust passing through the path is small and the amount of dust adhering is small.

The glass ribbon GR may have an upward (including diagonally upward) surface, and the

heat insulating materials

455 and 457 may be arranged above the upward surface. Dust tends to fall due to gravity, and the upward surface of the glass ribbon GR tends to catch the dust. Therefore, the effect of suppressing the generation of dust from the

heat insulating materials

455 and 457 is remarkably obtained. The

heat insulating materials

455 and 457 are preferably arranged directly above the glass ribbon GR, but may be arranged diagonally above.

Although not shown, the dross box 41 may have the same structure as the slow cooling furnace 45. For example, the dross box 41 has a ceiling, a lower wall and side walls, and at least one of the ceiling, the lower wall and the side walls may include a metal box and a heat insulating material filled inside the box. Moreover, the side wall of the dross box 41 may have an opening through which the rotating shaft of the lift out roll 42 is inserted, and the opening may have a heat insulating material that suppresses the outflow of heat.

Next, an example of the upper structure of the molding device 3 of FIG. 2 will be described with reference to FIG. The molding device 3 has a ceiling 312 of the molding furnace 31 and a heater 32 suspended from the ceiling 312 . A plurality of heaters 32 are arranged in a matrix in the conveying direction (X-axis direction) and the width direction (Y-axis direction) of the glass ribbon GR. The molding device 3 may have a heat insulating material 35 between adjacent heaters 32 . The heat insulating material 35 may be arranged between the heaters 32 adjacent in the Y-axis direction, or may be arranged between the heaters 32 adjacent in the X-axis direction. The heat insulating material 35 restricts heat transfer between adjacent heaters 32 .

The heat insulating material 35 contains inorganic fibers, similar to the heat insulating material 314 (see FIG. 3). The inorganic fibers contained in the heat insulating material 35 have an Al ₂ O ₃ content of 60% by mass or more and an SiO ₂ content of 40% by mass or less. Details will be described in the section of Examples, but if the Al ₂ O ₃ content is 60% by mass or more, changes in the crystal structure of the inorganic fibers due to temperature changes can be suppressed, and dust generation can be suppressed.

The heat insulating material 35 is exposed to the atmosphere to which the glass ribbon GR is exposed. That is, the heat insulating material 35 is exposed to the glass ribbon GR, and there is a path from the heat insulating material 35 to the glass ribbon GR (a space continuously connecting from the heat insulating material 35 to the glass ribbon GR). According to the present embodiment, generation of dust can be suppressed. Therefore, even if there is a path from the heat insulating material 35 to the glass ribbon GR, the amount of dust passing through the path is small and the amount of dust adhering is small.

The glass ribbon GR has an upward (including obliquely upward) surface, and the heat insulating material 35 is arranged above the upward surface. Dust tends to fall due to gravity, and the upward surface of the glass ribbon GR tends to catch the dust. Therefore, the effect of suppressing the generation of dust from the heat insulating material 35 is remarkably obtained. The heat insulating material 35 is preferably arranged directly above the glass ribbon GR, but may be arranged diagonally above.

Next, an example of the buffer film forming part 48 of the slow cooling device 4 of FIG. 2 will be described with reference to FIG. The buffer film forming unit 48 has a supply pipe 481 for spraying a buffer onto the lower surface of the glass ribbon GR. The buffer reacts with the lower surface of the glass ribbon GR to form a buffer film on the lower surface of the glass ribbon GR. The buffer film reduces the collision between the glass ribbon GR and the layer roll 46, and suppresses the lower surface of the glass ribbon GR from being damaged. For example, sulfur oxide gas is used as the buffering agent. The sulfur oxide gas may be either _SO2 gas or _SO3 gas. The sulfur oxide gas reacts with the lower surface of the glass ribbon GR to form a buffer film on the lower surface of the glass ribbon GR. The buffer film contains sulfate crystals and the like.

The buffer film forming portion 48 includes a buffer supply chamber 482 in which a supply pipe 481 is arranged, an upstream heat insulating material 483 provided upstream (X-axis negative direction side) of the buffer supply chamber 482, and a buffer supply chamber 483. 482 and a downstream heat insulating material 484 provided on the downstream side (X-axis positive direction side). The upstream heat insulating material 483 and the downstream heat insulating material 484 efficiently and uniformly form a buffer film by filling the buffer supply chamber 482 with the buffer. The upstream heat insulating material 483 and the downstream heat insulating material 484 are not in contact with the lower surface of the glass ribbon GR, but they may be in contact.

An upper heat insulator 485 may be arranged directly above the downstream heat insulator 484 . The upper heat insulating material 485 is arranged above the glass ribbon GR. The upper heat insulating material 485 interrupts the gas flow above the glass ribbon GR.

The upstream heat insulating material 483, the downstream heat insulating material 484, and the upper heat insulating material 485 contain inorganic fibers, similar to the heat insulating material 314 (see FIG. 3). The inorganic fibers have an Al ₂ O ₃ content of 60% by mass or more and an SiO ₂ content of 40% by mass or less. Details will be described in the section of Examples, but if the Al ₂ O ₃ content is 60% by mass or more, changes in the crystal structure of the inorganic fibers due to temperature changes can be suppressed, and dust generation can be suppressed.

The upstream heat insulating material 483, the downstream heat insulating material 484, and the upper heat insulating material 485 are exposed to the atmosphere to which the glass ribbon GR is exposed. In other words, the upstream heat insulating material 483, the downstream heat insulating material 484, and the upper heat insulating material 485 are exposed from the glass ribbon GR, and the paths leading from these heat insulating materials to the glass ribbon GR (from these heat insulating materials to the glass ribbon GR There is a space that continuously connects to According to the present embodiment, generation of dust can be suppressed. Therefore, even if there is a path from the heat insulating material to the glass ribbon GR, the amount of dust passing through that path is small and the amount of dust adhering is small.

The glass ribbon GR has an upward (including obliquely upward) surface, and the upper heat insulating material 485 is arranged above the upward surface. Dust tends to fall due to gravity, and the upward surface of the glass ribbon GR tends to catch the dust. Therefore, the effect of suppressing the generation of dust from the upper heat insulating material 485 is remarkably obtained. The upstream heat insulating material 483 is preferably arranged directly above the glass ribbon GR, but may be arranged diagonally above.

Experimental data will be described below. Example 1 below is a comparative example, and Example 2 is an example. In Example 1, isowool (registered trademark) 1260 manufactured by Isolite Industry Co., Ltd. was prepared as a heat insulating material. The chemical composition of the heat insulating material of Example 1 is _Al2O3 : _43.8 % by mass, _SiO2 : 55.3% by mass, _Fe2O3 : _0.2 % by mass, _Na2O : 0.1% by mass. , TiO ₂ : 0.5% by mass, and CaO: 0.1% by mass. On the other hand, in Example 2, MAFTEC (registered trademark) manufactured by Mitsubishi Chemical Corporation was prepared as a heat insulating material. The chemical composition of the thermal insulation material of Example 2 was Al ₂ O ₃ : 72.0% by mass and SiO ₂ : 28.0% by mass.

FIG. 8 shows the X-ray diffraction spectrum of the heat insulating material of Example 1. The X-ray diffraction spectra were obtained by storing at room temperature before heat treatment, heating at 800° C. in air for 24 hours, heating at 1000° C. in air for 24 hours, and heating at 1200° C. in air for 24 hours. Each was measured. In FIG. 8, the horizontal axis is the diffraction angle (2θ), and the vertical axis is the diffracted X-ray intensity. The X-rays were CuKα rays. The heat insulating material of Example 1 had an Al ₂ O ₃ content lower than 60% by mass, and as shown in FIG. 8, when the heating temperature reached 1000° C. or higher, the crystal structure changed. The change in crystal structure was significant at 1200°C.

FIG. 9 shows the X-ray diffraction spectrum of the heat insulating material of Example 2. The X-ray diffraction spectra were obtained by storing at room temperature before heat treatment, heating at 800° C. in air for 24 hours, heating at 1000° C. in air for 24 hours, and heating at 1200° C. in air for 24 hours. Each was measured. In FIG. 9, the horizontal axis is the diffraction angle (2θ), and the vertical axis is the diffracted X-ray intensity. The X-rays were CuKα rays. The heat insulating material of Example 2 had an Al ₂ O ₃ content of 60% by mass or more, and as shown in FIG. 9, the crystal structure hardly changed even when the heating temperature was 1000° C. or more.

　Fig. 10 shows the dust scattering rate of the thermal insulation materials of Examples 1 and 2. The dust scattering rate was obtained by heat-treating the heat insulating material at 1000° C. in the air, then vibrating it with a vibration generator while it was housed in a case, and measuring the amount of dust falling on the case. The vibration conditions were a frequency of 60 Hz, a current of 2.0 A, and a duration of 30 minutes. In both Examples 1-1 and 1-2, isowool (registered trademark) 1260 manufactured by Isolite Industry Co., Ltd. was used as a heat insulating material. In both Examples 2-1 and 2-2, MAFTEC (registered trademark) manufactured by Mitsubishi Chemical Corporation was used as a heat insulating material. From FIG. 10, it can be seen that the heat insulating material of Example 2 has a lower dust scattering rate than the heat insulating material of Example 1. This is probably because, unlike the heat insulating material of Example 1, the heat insulating material of Example 2 hardly changes its crystal structure and does not deteriorate even when heat-treated at 1000° C. or higher, as described above.

The following notes are disclosed with respect to the above embodiments.
[Appendix 1]
A glass manufacturing apparatus comprising a melting apparatus for obtaining molten glass by melting frit, a forming apparatus for forming the molten glass into a glass article having a desired shape, and a slow cooling apparatus for slowly cooling the glass article. There is
At least one of the melting device, the molding device, and the slow cooling device includes a heat insulating material containing inorganic fibers,
The inorganic fiber contains _Al2O3 and _SiO2 , the _Al2O3 content of the inorganic fiber is 60% by mass _or more, and _the _SiO2 content of the inorganic fiber is 40% by mass or less. Device.
[Appendix 2]
The glass manufacturing apparatus according to appendix 1, wherein the inorganic fiber has an Al ₂ O ₃ content of 90% by mass or less and a SiO ₂ content of 10% by mass or more.
[Appendix 3]
3. The glass manufacturing apparatus according to

appendix

1 or 2, wherein the heat insulating material is exposed to an atmosphere to which the molten glass or the glass article is exposed.
[Appendix 4]
the molten glass or the glass article has an upward facing surface;
4. The glass manufacturing apparatus according to any one of Appendices 1 to 3, wherein the heat insulating material is arranged above the molten glass or the glass article.
[Appendix 5]
A glass manufacturing method, comprising manufacturing the glass article using the glass manufacturing apparatus according to any one of Appendices 1 to 4.

Although the glass manufacturing apparatus and the glass manufacturing method according to the present disclosure have been described above, the present disclosure is not limited to the above embodiments and the like. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These also naturally belong to the technical scope of the present disclosure.

This application claims priority based on Japanese Patent Application No. 2022-014214 filed with the Japan Patent Office on February 1, 2022, and the entire contents of Japanese Patent Application No. 2022-014214 are incorporated into this application. .

1 glass manufacturing device 2 melting device 3 molding device 4 slow cooling device

Claims

A glass manufacturing apparatus comprising a melting apparatus for obtaining molten glass by melting frit, a forming apparatus for forming the molten glass into a glass article having a desired shape, and a slow cooling apparatus for slowly cooling the glass article. There is
At least one of the melting device, the molding device, and the slow cooling device includes a heat insulating material containing inorganic fibers,
The inorganic fiber contains Al2O3 and SiO2 , the Al2O3 content of the inorganic fiber is 60% by mass or more, and the SiO2 content of the inorganic fiber is 40% by mass or less. Device.
The glass manufacturing apparatus according to claim 1, wherein the inorganic fibers have an Al2O3 content of 90 mass% or less, and a SiO2 content of the inorganic fibers of 10 mass% or more.
The glass manufacturing apparatus according to claim 1 or 2, wherein the heat insulating material is exposed to an atmosphere to which the molten glass or the glass article is exposed.
the molten glass or the glass article has an upward facing surface;
The glass manufacturing apparatus according to claim 1 or 2, wherein the heat insulating material is arranged above the molten glass or the glass article.
A glass manufacturing method, comprising manufacturing the glass article using the glass manufacturing apparatus according to claim 1 or 2.