JP2022063452A - Glass panel and production method and production apparatus of the same - Google Patents

Abstract

To facilitate evacuating air from an internal space in a glass panel made by laminating a plurality of glass plates and having the internal space formed in between, and to simplify a production apparatus of the same.SOLUTION: A glass panel includes two sheets of glass plates and sealing parts interposed between the glass plates, and has an internal space surrounded by two sheets of the glass plates and the sealing parts. A cap to close an opening formed on the glass plate and a sealing glass for the cap are provided on at least one of two sheets of the glass plates, the sealing parts include glass for sealing, and the sealing glass for the cap has a softening point lower than that of the glass for sealing.SELECTED DRAWING: Figure 5

Description

The present invention relates to a glass panel and a method and apparatus for manufacturing the same.

Double glazing is applied to windows for building materials that require high heat insulation performance, commercial refrigerators, doors for freezers, windows for transportation equipment such as automobiles, and other openings that require energy saving. In recent years, with the demand for window glass having excellent heat insulating performance, the frequency of use of double glazing having heat insulating performance has increased, and it is rapidly becoming widespread.

As double glazing, a double glazing panel in which an internal space formed between two opposing flat glasses is filled with a rare gas such as air or argon, or a vacuum insulated double glazing panel in which the space is vacuum exhausted. There is.

In the vacuum insulated double glazing, low melting point glass having low gas permeability is used as the vacuum sealing portion in order to seal the space formed by the pair of flat glass (hereinafter referred to as “gap portion”). In addition, spacers are arranged at equal intervals in the gap so that the gap is not crushed and the glass panel is not cracked due to the pressure difference from the atmospheric pressure during vacuum sealing, and the distance between the glass panels is about 0.2 mm. It is held to a certain thickness.

Further, in order to improve the heat insulating performance, there is also a double glazing provided with two heat insulating layers, a rare gas packed layer and a vacuum layer of about 10 mm.

Vacuum-insulated double glazing is generally manufactured by using an exhaust pipe to evacuate the gaps in the glass panel into a vacuum.

In Patent Document 1, after the inside of the sealable space between the flat glass is decompressed, the space is divided into the space by the partition wall which is a region forming material arranged in the space, except for the exhaust port region and the exhaust port region including the exhaust port. A method for producing a double glazing is disclosed, which is divided into a decompression region and a decompression region. Further, in Patent Document 1, when the partition wall is not melted, a ventilation portion (slit) is formed in the partition wall, and the frit seal for sealing the pair of flat glass and the partition wall both have the same low melting point. It is disclosed that a glass frit is used.

Patent Document 2 describes a pair of flat glass sheets that are opposed to each other via a spacer to form a hollow layer between them, a low melting point glass that joins the peripheral edges of the pair of flat glass plates, and a gas in the hollow layer. The vacuum multilayer glass is manufactured by heating each member of the vacuum multilayer glass to about 200 ° C. and at the same time irradiating ultraviolet rays while vacuum exhausting the gas in the hollow layer through the exhaust hole. The lid (sealing portion) made of transparent plate glass provided at the opening of the exhaust hole, which is glass, has a melting point higher than that of the sealing material for sealing, specifically, the low melting point glass constituting the bonding sealing material. It is disclosed that the exhaust hole is sealed in a closed state by being adhesively fixed to the plate glass by a crystalline low melting point glass (sealing portion) which is high and has a lower melting point than the lid or the plate glass. ..

Japanese Patent No. 5821010 Japanese Unexamined Patent Publication No. 2005-139005

In the method disclosed in Patent Document 1, since the space formed by the two plate glasses is divided into an exhaust port region and a decompression region by the region forming material, a step of forming the region forming material is required. .. Further, when depressurizing the space formed by the two plate glasses, it is necessary to exhaust the air through a slit having a small width, so that the speed of the vacuum exhaust may be slowed down.

In the vacuum double glazing disclosed in Patent Document 2, since a sealing material for sealing having a higher melting point than the low melting point glass constituting the bonding sealing material is used, it is necessary to irradiate ultraviolet rays, and the structure of the manufacturing apparatus is complicated. There is room for improvement in that.

An object of the present invention is to facilitate vacuum exhaust of an internal space in a glass panel in which a plurality of glass substrates are laminated and an internal space is provided between them, and to simplify the manufacturing apparatus thereof. And.

The glass panel of the present invention includes two glass plates and a sealing portion sandwiched between the two glass plates, and has an internal space surrounded by the two glass plates and the sealing portion. At least one of the glass plates is provided with a cap for closing the opening provided in the glass plate and a cap sealing glass, and the sealing portion includes the sealing glass and is used for cap sealing. Glass has a lower softening point than sealing glass.

According to the present invention, in a glass panel in which a plurality of glass substrates are laminated and an internal space is provided between them, the vacuum exhaust of the internal space is facilitated and the manufacturing apparatus thereof is simplified. Can be done.

It is a top view which shows the state before sealing of the double glazing which concerns on one Embodiment. FIG. 1 is a cross-sectional view taken along the line AA'in FIG. It is a top view which shows the state after sealing the double glazing of FIG. FIG. 3 is a cross-sectional view taken along the line AA'in FIG. It is sectional drawing which shows the state which the exhaust port of the double glazing of FIG. 4 is vacuum-sealed. It is a top view which shows the state before sealing of the double glazing of a modification. It is a top view which shows the state before sealing of the double glazing of another modification. It is a graph which shows the relationship between the temperature and viscosity of a glass. It is a graph which shows an example of the differential thermal analysis (DTA) of a glass composition. It is a graph which shows the relationship between the temperature and the amount of gas emission in a sealing process. It is a perspective view which shows the state of the 1st glass substrate alone in the process of manufacturing the double glazing which concerns on one Embodiment. It is a perspective view which shows the state of the 2nd glass substrate alone in the process of manufacturing the double glazing which concerns on one Embodiment. It is sectional drawing which shows the state which two glass substrates were superposed and installed in the heating apparatus in the middle of manufacturing of the double glazing which concerns on one Embodiment. It is a graph which shows the specific example of the temperature profile of a sealing process. It is sectional drawing which shows the state in the process of manufacturing when the heat insulating layer of a double glazing is made into two layers. It is sectional drawing which shows the multi-stage panel sealing apparatus. It is a schematic block diagram which shows an example of the single-wafer type panel sealing apparatus. It is a graph which shows the temperature profile in the inside of the tunnel type heating furnace of FIG.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the embodiments taken up here, and can be appropriately combined and improved without changing the gist.

FIG. 1 is a top view showing a state before sealing of the double glazing according to the embodiment.

As shown in this figure, before sealing, the sealing material 104 is installed on the peripheral edge of the first glass substrate 1 constituting the double glazing. A plurality of spacers 3 are regularly arranged vertically and horizontally in the inner region of the sealing material 104. Further, an exhaust port 5 (opening) is provided at one place in the inner region of the sealing material 104 near the corner of the first glass substrate 1.

FIG. 2 is a cross-sectional view taken along the line AA'of FIG.

As shown in FIG. 2, the double glazing is sandwiched between the first glass substrate 1, the second glass substrate 2, the first glass substrate 1 and the second glass substrate 2 before sealing. The sealing material 104 is provided. Further, a plurality of spacers 3 are attached to the lower surface of the first glass substrate 1. The sealing material 104 is also fixed to the lower surface of the first glass substrate 1 by temporary firing. The sealing material 104 is for blocking the internal space (space portion) formed between the first glass substrate 1 and the second glass substrate 2 after sealing from the outside.

The sealing material 104 is formed so that the coating height thereof is about twice the height of the spacer 3.

FIG. 3 is a top view showing the state of the double glazing after sealing.

The difference from FIG. 1 in this figure is that the sealing material 104 is changed to the sealing portion 4.

FIG. 4 is a cross-sectional view taken along the line AA'of FIG.

As shown in FIG. 4, in the double glazing after sealing, the sealing material 104 is crushed and spread to the height of the spacer 3 to form the sealing portion 4. As a result, the thickness of the internal space formed between the first glass substrate 1 and the second glass substrate 2 is equal to the height of the spacer 3. The internal space is in a vacuum state (decompression state) by the operation described later. As used herein, the term "vacuum state" means that the pressure is lower than the atmospheric pressure.

FIG. 5 is a cross-sectional view showing a state in which the exhaust port of the double glazing of FIG. 4 is vacuum-sealed.

In this figure, a cap 21 is attached to the upper surface of the first glass substrate 1 to seal the exhaust port 5 and maintain a vacuum state in the internal space of the double glazing. The cap 21 is fixed to the upper surface of the first glass substrate 1 via the cap sealing glass 22.

When forming the sealing portion 4, since the set temperature is high, the cap 21 is located at a position away from the double glazing (glass panel) in the space where the vacuum is maintained in order to avoid the influence of the heat. And the sealing glass 22 for the cap is installed. Then, when the exhaust port 5 is vacuum-sealed, the temperature is lowered to an appropriate set temperature, and the cap 21 and the cap sealing glass 22 are moved to a position where the exhaust port 5 is closed. In this case, the moving means is a simple manipulator, for example, a mechanism that generates a negative pressure on the upper surface portion of the cap 21 by sucking air at the support portion to attract the cap 21, and a mechanism that grips both side surfaces of the cap 21. A manipulator having the above is conceivable.

The size of the exhaust port 5 is smaller than the width of the sealing material 104, and it is desirable that the circle has a diameter equal to or larger than the thickness of the first glass substrate and the second glass substrate. However, the relationship between the sizes of the exhaust ports 5 is a condition when the sealing material 104 is formed so that the coating height is about twice the height of the spacer 3. If the size of the exhaust port 5 is desired to be larger than the width of the sealing material 104, the coating height of the sealing material 104 needs to be increased in proportion to the size of the exhaust port 5. Although the shape of the exhaust port 5 is described by a circle, it may be an ellipse, an elongated hole, or the like.

The cap sealing glass 22 uses a glass material that melts at a lower temperature than the sealing material 104. As a result, the exhaust port 5 can be covered with the cap 21 at a temperature lower than the softening point of the sealing material 104, and the sealing glass 22 for the cap can be welded. This enables vacuum sealing with the cap 21 and the cap sealing glass 22 in a temperature range where the amount of gas released from the sealing material 104 is small. Here, the cap sealing glass 22 has a higher content of Ag ₂ O than the sealing material 104.

Here, it is desirable that the softening point of the sealing material 104 is 300 ° C. or lower. Further, it is desirable that the softening point of the cap sealing glass 22 is 250 ° C. or lower. It is desirable that the sealing glass 22 for a cap has an Ag ₂ O content of 26 mol% or more.

FIG. 6 is a top view showing a state before sealing of the double glazing of the modified example.

In this figure, a plurality of exhaust ports 5 are provided.

It is desirable that the exhaust port 5 is provided at a position adjacent to the sealing material 104. As long as the exhaust port 5 is installed at such a position, the position and number thereof are not particularly limited. By increasing the number of exhaust ports 5, the efficiency of vacuum exhaust can be improved.

FIG. 7 is a top view showing a state before sealing of the double glazing of another modified example.

As shown in this figure, the exhaust port 5 may be provided at a position adjacent to the side of the temporarily fired sealing material 104 instead of the corner portion.

<Glass substrate>
As the first glass substrate and the second glass substrate, flat glass usually used for double glazing can be used. As the plate glass, for example, float plate glass, template glass, frosted glass, tempered glass, meshed plate glass, wire-inserted plate glass and the like can be used. Further, it is also possible to use a flat glass having a heat ray reflecting film laminated on the surface.

<Spacer>
Spacers are used to maintain the space between the two glass substrates. As the spacer, for example, a spherical, linear, or net-like spacer can be used. The spacer is not particularly limited as long as it is a material having a hardness lower than that of a double glazing plate glass and having an appropriate compressive strength. For example, glass, metal, alloy, steel, ceramics, plastic and the like can be used.

The size of the spacer can be selected according to the thickness of the space between the two glass substrates. For example, when the distance between two glass substrates is desired to be 200 μm, a spacer having a diameter of about 200 μm may be used as the spacer. The spacing between the spherical, linear, and net-like spacers is 200 mm or less, preferably 100 mm or less. Further, it is desirable that the distance between the spacers is 10 mm or more. The arrangement of the spacers may be regular or irregular as long as it is within the range of the above-mentioned spacing.

Further, in order to obtain a space portion having an appropriate thickness having a vacuum state, it is effective to introduce spherical beads or the like having a uniform particle size in the spacer or the sealing portion.

<Sealing part>
The sealing portion 4 (FIG. 3) is formed of a sealing material 104 (FIG. 1) containing low melting point glass. Here, the low melting point glass refers to a glass composition that softens and flows at 600 ° C. or lower. From the viewpoint of environmental load, it is preferable that the low melting point glass does not contain lead. In the present specification, the lead-free glass composition means a glass composition intentionally free of lead, and includes a glass composition containing 1000 ppm or less of lead that is unintentionally mixed.

As the sealing material, it is necessary to select a material that can be sealed at a temperature below the heat resistant temperature of the glass substrate. Since the glass substrate is easily damaged by rapid heating or cooling, it is necessary to gradually heat and cool the sealing. In order to improve the productivity of the double glazing panel for vacuum insulation, sealing at a low temperature is required as much as possible. Therefore, as the low melting point glass, it is preferable to use an oxide glass containing at least vanadium oxide (V ₂ O ₅ ) and tellurium oxide (TeO ₂ ).

The low melting point glass preferably contains silver oxide (Ag ₂ O) in addition to vanadium oxide (V ₂ O ₅ ) and tellurium oxide (TeO ₂ ). Glasses with lower characteristic temperatures such as transition points, yield points, and softening points tend to have better softening fluidity at lower temperatures. On the other hand, if the characteristic temperature is lowered too much, crystallization is likely to occur during heating and firing, and the softening fluidity at a low temperature is lowered. Further, the lower the characteristic temperature of glass, the lower the chemical stability such as water resistance and acid resistance. Furthermore, the impact on the environmental load tends to increase. For example, in the conventional PbO _- B ₂ O3 system low melting point glass composition, the higher the harmful PbO content, the lower the characteristic temperature can be, but the crystallization tendency is large, and the chemical stability is lowered, so that the environment The effect on the load is even greater.

However, the oxide glass containing vanadium oxide, tellurium oxide and silver oxide can both lower the characteristic temperature and suppress crystallization.

Silver oxide contributes to lowering the characteristic temperature of transition points, yield points, softening points, etc. and improving chemical stability. Vanadium oxide has a function of preventing silver oxide from being reduced and precipitating metallic silver during glass production.

If silver oxide contained as a glass component does not exist in the glass in the state of silver ions, the desired effect of lowering the temperature cannot be obtained. Increasing the content of silver oxide, that is, increasing the amount of silver ions in the glass, can reduce the temperature, but at that time, it is necessary to increase the content of vanadium oxide in order to prevent or suppress the precipitation of metallic silver. There is. When producing glass, it is desirable to mix monovalent silver ions in a ratio of 2 or less to 1 pentavalent vanadium ion.

Tellurium oxide is a vitrifying component for vitrification during glass production. Therefore, glass cannot be formed without mixing tellurium oxide. It is effective to have one or less tetravalent tellurium ion with respect to one pentavalent vanadium ion. Beyond this, tellurium and silver compounds may precipitate.

Considering the functions of vanadium oxide, tellurium oxide and silver oxide described above, in the lead-free low melting point glass composition, the total of V2 O ₅ , TeO ₂ and Ag ₂ O is 85 mol% or _more , and TeO ₂ It is desirable that the total content of Ag 2 O and Ag ₂ O is 1 to 2 times the content of V ₂ O ₅ , respectively. If it falls below or exceeds these composition ranges, problems such as precipitation of metallic silver during glass production, deterioration of the low temperature effect, remarkable crystallization during heating and firing, and deterioration of chemical stability may occur. There is sex.

Further, the glass composition contains one or more of potassium, tungsten, iron, aluminum and lanthanoid oxides as additional components, and the content of the additional components is 0.1 to 7.0 mol%. Is preferable. This is because the crystallization tendency can be reduced by containing a small amount of any one or more of aluminum and lanthanoid oxides. Further, the bonding strength can be improved by containing a small amount of potassium, and tungsten and iron can improve the water resistance of the glass material itself. When the oxide content of aluminum and lanthanoid is less than 0.1 mol%, there is almost no effect of reducing the crystallization tendency. On the other hand, if it exceeds 3.0 mol%, the characteristic temperature such as the softening point may rise, and conversely, the crystallization tendency may increase. Among the oxides of aluminum and lanthanoid, the components that are more effective in reducing the crystallization tendency are Al ₂ O ₃ , Y ₂ O ₃ , La ₂ O ₃ , CeO ₂ , Er ₂ O in the form of the following oxides. ₃ and Yb ₂ O ₃ can be mentioned, and it is effective to contain 0.1 to 2.0 mol% of any one or more of them. Among them, the content of Al ₂ O ₃ and La ₂ O ₃ is particularly effective, and the effective content is 0.1 to 1.0 mol%.

Further, in order to facilitate the acquisition of a lead-free low melting point glass composition in a uniform glass state (amorphous state) and not to promote the crystallization tendency of the obtained glass, BaO, WO ₃ in terms of oxide is used. It is effective to include any one or more of P 2 O ₅ and P ₂ O 5 in an amount of 13 mol% or less.

From the above, it is possible to set the second endothermic peak temperature (softening point) of the lead-free glass composition to 300 ° C. or lower by differential thermal analysis (DTA). Further, the crystallization start temperature by DTA can be set to be 100 ° C. or higher higher than the second endothermic peak temperature (softening point). As a result, it is possible to provide a sealing material having good softening fluidity at a low temperature and a high crystallization temperature. After sealing, the low melting point glass may be crystallized.

The sealing material used for the sealing portion 4 may contain low thermal expansion ceramic particles in addition to the glass composition. The low thermal expansion ceramic particles may be mixed in order to match the thermal expansion coefficients of the first glass substrate and the second glass substrate.

Here, the characteristic temperature in the present disclosure will be described.

FIG. 8 is a graph showing the relationship between the temperature and the viscosity of the glass.

As shown in this figure, the viscosity decreases as the temperature rises.

FIG. 9 is a graph showing an example of differential thermal analysis (DTA) of a glass composition.

Generally, as the DTA of glass, glass particles having a particle size of about several tens of μm are used, and high-purity alumina (α-Al ₂ O ₃ ) particles are used as a standard sample, and the temperature rises to 5 ° C./min in the atmosphere. Measured by speed. The horizontal axis represents the temperature during temperature rise, and the vertical axis represents the potential difference based on the temperature difference representing heat generation / endothermic.

In this figure, the transition point T _g is the start temperature of the first heat absorption peak or the temperature at which the temperature changes from the glass to the supercooled liquid, and the heat absorption peak temperature or the point at which the expansion of the glass is stopped is the yield point M _g . (Ii) The heat absorption peak temperature or the temperature at which softening begins is the softening point T _s , the temperature at which the glass becomes a sintered body is the sintering point T _sint , the temperature at which the glass melts is the flow point T _f , and the temperature suitable for forming the glass. The work point T _w and the start temperature of the exothermic peak due to crystallization are shown as the crystallization start temperature T _cry . Each characteristic temperature is obtained by the tangential method.

The characteristic temperature of T _g , Mg, T _s , _{etc. is defined by the viscosity of the glass, T g is 10 13.3 poise, M g is 10 11.0 poise, T s is} ¹⁰ _7.65 ^poise _, ^and so on. T _sint is a temperature corresponding to 10 ⁶ poise, T _f is a temperature corresponding to 10 ⁵ poise, and T _w is a temperature corresponding to 10 ⁴ poise. The crystallization tendency is determined from T _cry and the size of the exothermic peak due to crystallization, that is, the calorific value thereof. The high T _cry , that is, the increase in the temperature difference between T _s and T _cry , and the small calorific value for crystallization represent the glass that is difficult to crystallize.

In a normal sealing step in producing double glazing, the glass composition used as a sealing material is heated in a temperature range from the vicinity of the softening point T _s to the working point T _w . In FIG. 9, the temperature range is referred to as "Working range".

FIG. 10 is a graph showing the relationship between the temperature and the amount of gas released in the sealing step.

When the glass panel is heated, the released gas component 11 (physically adsorbed component) is detected up to the softening point _Ts of the glass composition used as the sealing material. The released gas component 11 is mainly water or the like physically adsorbed on the surface inside the glass panel. When the temperature is further raised, the released gas component 12 (chemically adsorbed component) chemically adsorbed on the surface inside the glass panel comes out. The released gas component 12 is hardly emitted in the vicinity of the pour point T _f of the glass composition. Further, when the temperature exceeds the working point T _f , the low melting point glass composition is reduced, and the oxygen-releasing gas component 13 (low melting point glass reducing component) mainly reduced from the glass comes out.

Looking at the timing at which the released gas is emitted in this figure, the peripheral edge sealing temperature can be set to a vicinity of the softening point T _s where the released gas is small, so that the sealing can be performed in a state of high vacuum. Further, the vacuum sealing of the exhaust port can be performed at a temperature lower than the peripheral edge sealing temperature, so that the vacuum sealing can be performed in a state of a higher degree of vacuum.

Here, in order for the sealing material 104 to be deformed to reach the height of the spacer 3, it is necessary to heat it to the vicinity of the pour point or heat it to the vicinity of the softening point to pressurize the sealing portion 4. When the former is heated to the vicinity of the pour point, as shown in this figure, the released gas component 12 comes out, and if it is sealed in that state, the degree of vacuum between the glass substrates becomes low. In the latter case, when the glass is heated to the vicinity of the softening point, the amount of released gas component 11 is reduced. Therefore, if the peripheral edge portion can be sealed in this state, the glass substrates can be maintained in a high degree of vacuum.

In order to pressurize the sealing portion 4, after heating to the vicinity of the softening point, the glass substrates are evacuated to a vacuum, the inside of the glass substrates is evacuated, and the outside is in an atmospheric state. By using the pressing force, the sealing portion 4 can be fluidized and sealed even in the vicinity of the softening point.

Further, when vacuum-sealing using the cap 21, the cap 21 is arranged so as to cover the exhaust port 5. By using a glass material that melts at a lower temperature than the sealing material 104, the cap sealing glass 22 can reduce the amount of gas released from the sealing portion 4. As a result, it becomes possible to provide double glazing with a high degree of vacuum.

<Manufacturing method of double glazing>
In the double glazing of the present disclosure, the air in the internal space surrounded by the first glass substrate, the second glass substrate, and the sealing material is exhausted from the exhaust port in a state of being heated to a predetermined temperature, and the internal space is depressurized. It can be manufactured by closing the exhaust port in this state.

Specifically, the method for manufacturing the multilayer glass includes a step of applying a sealing material to the first glass substrate and then temporarily firing it, and an exhaust port at a position close to the sealing material temporarily fired on the first glass substrate. The process of forming the above glass substrate, the process of superimposing and fixing the first glass substrate and the second glass substrate, and the process of deforming the sealing material by raising the temperature in the heating device and exhausting the inside of the internal space with reduced pressure. Includes a vacuum exhaust process that closes the mouth.

FIGS. 11A to 11C show a state in the middle of manufacturing the double glazing according to the embodiment.

FIG. 11A shows a single state of the first glass substrate.

FIG. 11B shows a single state of the second glass substrate.

FIG. 11C shows a state in which two glass substrates are overlapped and installed in a heating device.

FIG. 11A shows a state in which the sealing material 104 containing the low melting point glass is applied to the first glass substrate 1 and then tentatively fired. In order to reliably close the exhaust port 5 with the cap 21, the cap sealing glass 22 uses a glass material that melts at a lower temperature than the sealing material 104. It is preferable that the Ag ₂ O content of the cap sealing glass 22 is higher than the Ag ₂ O content of the sealing material 104. Further, the exhaust port 5 is provided at a position close to the sealing material 104 after the temporary firing of the first glass substrate 1, and the spacer 3 is arranged. The sealing material 104 may be temporarily fired after the exhaust port 5 is provided on the first glass substrate 1.

FIG. 11B shows a state in which the heat ray reflecting film 6 is laminated on the surface of the second glass substrate 2. Although it is not necessary to laminate the heat ray reflecting film on the second glass substrate 2, by laminating the heat ray reflecting film, it is possible to obtain double glazing having higher heat insulating property.

In FIG. 11C, after the first glass substrate 1 and the second glass substrate 2 are overlapped with each other, the glass substrate is fixed with a clip 19 so as not to be displaced, and is carried into the heating device 9 (hot air circulation type heating device). It shows the state of the glass. An exhaust head 8 is connected to the exhaust port 5 via a ring-shaped sealing material 7. The exhaust head 8 is connected to the vacuum pump 10.

For the clip 19, it is preferable to use a stainless steel material or an Inconel (registered trademark) material in consideration of the heat resistance of the spring. As the heating device 9 for heating the glass panel in the atmosphere, a hot air circulation type heating furnace in which a heater is installed inside and a fan for making the temperature uniform is attached is preferably used.

When the heating temperature is 300 ° C. or lower, it is possible to use an O-ring of a fluororesin-based rubber such as PTFE having heat resistance as the ring-shaped sealing material 7, and it is possible to improve the vacuum adhesion. .. The exhaust head 8 is connected to the vacuum pump 10 via a flexible pipe in the heating device 9, and has a configuration capable of vacuum exhausting the internal space between the first glass substrate 1 and the second glass substrate 2. ..

The temperature inside the heating device 9 is raised to a temperature near the softening point of the glass composition contained in the sealing material 104, and the exhaust port 5 is closed with the internal space decompressed. Here, the temperature near the softening point means the temperature at the softening point ± 10 ° C.

In the vacuum exhaust step, it is preferable to raise the temperature to a temperature near the softening point of the peripheral low melting point glass (sealing material 104), maintain the temperature for a predetermined time, and then exhaust while maintaining the temperature.

FIG. 12 is a graph showing a specific example of the temperature profile of the sealing process.

Heat at a temperature rise rate T ₂ [° C / min] to a temperature T ₁ [° C] near the softening point T _s . After reaching the temperature T ₁ [° C.], the temperature is maintained for D ₁ while being heated in the atmosphere, and then vacuum exhaust between the glass substrates is started. The time for vacuum exhaust is from the start of vacuum exhaust at temperature T ₁ [° C] to the time D ₂ [minutes] until the sealing is completed, and then until about 10 to 30 minutes have passed since the start of cooling. It was between.

Times D ₁ and D ₂ are determined while observing the sealed state of the glass panel. Further, it is preferable to change it depending on the type of glass composition used as the sealing material and the panel size. Specifically, D ₁ is preferably 10 minutes to 30 minutes, and the cooling temperature rate T ₃ is preferably 1 ° C./min to 10 ° C./min.

As shown in FIG. 11C, the cap 21 moves in the direction of arrow 23 and connects to the exhaust port 5 at an appropriate timing for vacuum sealing. Then, the sealing glass 22 for a cap is melted and vacuum-sealed.

According to the manufacturing method as described above, in the step of sealing between the glass substrates, the exhaust port is also closed while maintaining the vacuum state, so that the step of sealing the exhaust pipe after sealing can be omitted. , The manufacturing process can be simplified. Further, since the temperature at which the exhaust port is sealed can reduce the gas released from the peripheral sealing glass (sealing material 104), the degree of vacuum in the double glazing panel after vacuum sealing can be increased. .. Further, since the exhaust is performed using the exhaust head, it is not necessary to use an exhaust pipe, and the number of parts can be reduced. Further, the cost can be reduced by stacking a plurality of double glazings in multiple stages in a hot air circulation type heating furnace and manufacturing a large number of glass panels at the same time.

In order to further improve the heat insulating property, it is effective to make the heat insulating layer multi-layered. However, according to the method for producing double glazing according to the embodiment of the present disclosure, the heat insulating layer (vacuum layer) is simply made into a multi-layered structure. Is possible. By simply changing the size of the clip 19, it is possible to cope with the multi-layering of the heat insulating layer.

FIG. 13 shows a state in the middle of manufacturing when the heat insulating layer of the double glazing is made into two layers.

The double glazing shown in this figure has a predetermined glass substrate 1, a second glass substrate 2 arranged so as to face the first glass substrate 1 with a predetermined space, and a second glass substrate 2. A third glass substrate 53, which is arranged so as to face each other across a space, is included. That is, it is a stack of three glass substrates. A first internal space 14 is formed between the first glass substrate 1 and the second glass substrate 2. A second internal space 15 is formed between the second glass substrate 2 and the third glass substrate 53. A sealing material 104 is provided on the peripheral edges of the first internal space 14 and the second internal space 15.

The first internal space 14 and the second internal space 15 are evacuated so as to be in a vacuum state. The first glass substrate 1 and the third glass substrate 53 are provided so as to be included in the projection portion of the sealing portion when projected in the stacking direction of the first glass substrate 1 and the second glass substrate 2. Has. The exhaust port 5 is closed by a cap at the time of sealing.

In this figure, the exhaust head 8 is provided on each of the first glass substrate 1 and the third glass substrate 53, but the configuration is not limited to this, and the exhaust head 8 is the first glass. By providing an exhaust port on the second glass substrate 2 by providing it only on the upper surface of the substrate 1 and not on the lower surface of the third glass substrate 53, the first internal space 14 and the second are provided by using one exhaust head 8. Vacuum exhaust of the internal space 15 can also be performed.

Further, in the sealing step, a batch type panel sealing device having a multi-stage shelf for installing a plurality of glass panels may be used. In order to supply vacuum-insulated double glazing as a building window material to the market, it is necessary to shorten the tact time as much as possible and mass-produce it.

FIG. 14 shows a batch type panel sealing device having a multi-stage shelf.

In this figure, a plurality of glass panels are installed on each shelf (not shown), and the internal space is evacuated by the vacuum pump 10 via the exhaust head 8 installed on each glass panel. It has become. As the heating device 9, a hot air circulation type heating furnace is used.

With such a configuration, it becomes possible to seal a plurality of glass panels at the same time, and mass productivity is improved. Since the hot air circulation type heating furnace can make the temperature distribution in the apparatus uniform at low cost, it can be processed at the same time even in multiple stages, and the yield can be improved.

A single-wafer type panel sealing device may be used for manufacturing the double glazing.

FIG. 15 shows an example of a single-wafer type panel sealing device.

The single-wafer type panel sealing device shown in this figure includes a panel carry-in mechanism 16, a tunnel type heating furnace 17, and a panel carry-out mechanism 18. The inside of the tunnel type heating furnace 17 also has an atmospheric pressure.

First, two glass substrates are fixed with clips and introduced into the tunnel type heating furnace 17 using the panel carrying mechanism 16. Inside the tunnel type heating furnace 17, heating and cooling are carried out by dividing into zones Z ₁ to Z ₄ . In zone Z3 _, the inside of the glass panel is evacuated by the vacuum pump equipment 20 corresponding to the single-wafer type. The glass panel that has passed through the tunnel type heating furnace 17 is taken out by the panel unloading mechanism 18.

FIG. 16 is a graph showing the temperature profile inside the tunnel heating furnace of FIG.

Since the temperature control shown in FIG. 16 and the vacuum exhaust step performed accordingly are the same as those shown in FIG. 12, the description thereof will be omitted.

Also in the single-wafer type panel sealing device shown in FIG. 15, the glass panels may be stacked in a plurality of stages and flowed. It is also possible to further shorten the tact time by making the process of overlapping and flowing in such a manner.

Hereinafter, examples will be described in detail.

In Examples 1 to 5, the double glazing panel shown in FIG. 5 was produced. The glass composition used as the sealing material was prepared by the following method.

(Preparation of glass composition)
Table 1 shows the compositions of the glass compositions (STA-1 to STA-5). The composition in the table is expressed as a molar percentage of each component in terms of oxide.

As starting materials, V ₂ O ₅ is manufactured by Shinko Kagaku Co., Ltd., Ag ₂ O is manufactured by Wako Pure Chemical Industries, Ltd., and other oxides are oxide powders manufactured by High Purity Chemical Research Institute Co., Ltd. ( Purity 99.9%) was used.

The powders of each oxide were mixed so as to have the molar percentage shown in Table 1 and placed in a platinum crucible. In mixing, the raw material powder was mixed in a crucible using a metal spoon in consideration of avoiding excessive moisture absorption.

A crucible containing the raw material mixed powder was placed in a glass melting furnace and heated and melted. The temperature was raised at a heating rate of 10 ° C./min, and the glass melted at a set temperature (700 to 900 ° C.) was held for 1 hour while stirring. Then, the crucible was taken out from the glass melting furnace, and the glass was cast into a graphite mold that had been preheated to 150 ° C.

Next, the cast glass was moved to a strain removing furnace heated to a strain removing temperature in advance and held for 1 hour to remove the strain. Then, it was cooled to room temperature at a rate of 1 ° C./min. The glass cooled to room temperature was pulverized to obtain a powder of a glass composition having the composition shown in this table.

(Evaluation of characteristic temperature)
For each of the obtained powders of the glass composition, the transition point, the yield point, the softening point, the sintering point, the pour point, the working point and the crystallization start temperature were measured by differential thermal analysis (DTA). The DTA measurement was carried out with the mass of the reference sample (α-alumina) and the measurement sample being 650 mg, respectively, at a heating rate of 5 ° C./min in the atmosphere.

The characteristic temperature of the transition point and the like was obtained by the tangential method as in the explanation of FIG.

Table 2 shows the results of each characteristic temperature.

(Preparation of glass composition used for sealing glass for caps)
The same glass compositions as those shown in Tables 1 and 2 were prepared, and the characteristic temperature was evaluated to obtain a glass composition used for the sealing glass for a cap.

Table 3 shows the composition of the glass compositions (HS-1 to HS-5). The composition in the table is expressed as a molar percentage of each component in terms of oxide.

Table 4 shows the results of each characteristic temperature. When STA-1 is used as the glass composition, the numbers correspond to the glass compositions for each encapsulation material, such as HS-1 as the encapsulation glass for camping.

(Preparation of sealing material)
A glass paste was prepared by mixing a glass composition, low thermal expansion ceramic particles, and a solvent. As the glass composition, STA-5 shown in Table 1 was used. The particle size of the glass composition was about 10 μm. As the low thermal expansion ceramic particles, zirconium tungate phosphate having a particle size of about 30 μm was used. In addition, α-terpineol was used as a solvent, and isobornylcyclohexanol was added as a viscosity adjusting agent.

The mixing ratio of STA-5 and zirconium tungate phosphate is 55:45 by volume, and the content of the solid content (total of STA-5 and zirconium tungstate phosphate) is 75 to 80% by volume. As described above, a glass paste for a sealing material was prepared. HS-5 was used as the sealing glass for the cap, and a glass paste was prepared by the same method as STA-5.

Further, in order to maintain the space between the glass substrates, soda lime glass spherical beads having a particle size of about 180 to 200 μm were mixed in the glass paste for the sealing material. The ratio was 1 part by volume for the encapsulating material and 20 parts by volume for the spacer with respect to 100 parts by volume of the solid content.

(Manufacturing of vacuum insulated double glazing panel)
In this embodiment, a soda lime glass substrate having a size of 800 mm × 1000 mm × 3 mmt was used as the glass substrate to be overlapped. Each substrate was subjected to ozone cleaning treatment before the sealing step to remove contaminants such as organic substances before use.

As shown in FIG. 11A, the prepared sealing material was applied to the soda lime glass substrate side and calcined. After the tentative firing, an exhaust port was provided on the sodaram glass substrate at a position close to the tentatively fired sealing material. Since the soda lime glass substrate is easily damaged by deformation, a plurality of spacers are two-dimensionally arranged at equal intervals in the space formed by the two soda lime glass substrates. For fixing the spacer, the same sealing material as that constituting the sealing portion was used. Further, in order to make the distance between the two soda lime glass substrates, that is, the thickness of the space portion about 200 μm, spherical beads having a diameter of less than 200 μm were mixed in the spacer. The spherical beads are made of stainless steel. A heat ray reflecting film was provided on the soda lime glass substrate side.

A glass panel was formed by stacking two soda lime glass substrates and fixing them with a plurality of clips.

After that, the glass panel was put in the heating device. In the heating device, the internal space of the glass panel was evacuated by a vacuum pump while heating the glass panel with a hot air circulation type heater.

The above heating was performed according to the temperature profile shown in FIG. The glass paste for sealing material used was heated to a temperature T ₁ [° C.] near the softening point T _s at a heating rate T ₂ [° C./min]. T ₁ was 270 ° C. and T ₂ was 5 ° C./min. The temperature was kept at T ₁ [° C.] for hours D ₁ [minutes], and then vacuum exhaust was started. During vacuum exhaust, the temperature was T ₁ [° C.] and the time D ₂ [minutes] was maintained. Then, at an appropriate timing for vacuum sealing, the cap attached with the sealing glass for the cap of HS-5 was moved and connected to the exhaust port. D ₁ was set to 15 minutes, D ₂ was set to 30 minutes, and the cooling rate T ₃ was set to 5 ° C./min.

(Evaluation of vacuum insulated double glazing panel)
The appearance of 10 vacuum-insulated double glazing panels produced was inspected. As a result, no cracks or cracks were observed, and there was no problem in appearance. Further, due to the spherical beads contained in the sealing portion and the spherical beads contained in the spacer, the distance between the two soda lime glass substrates was almost uniform in thickness. As a result, a vacuum-insulated double glazing panel having a predetermined space was obtained.

In order to confirm the reliability of the sealed portion, the three vacuum-insulated double glazing panels produced were immersed in warm water at 50 ° C. for 30 days. It was confirmed that the inside of the panels was maintained in a vacuum state without water entering the inside of all three panels. In addition, a temperature cycle test was carried out 1000 times in a temperature range of -50 ° C to + 100 ° C for another three vacuum-insulated double glazing panels. In this test as well, the inside of all three panels was kept in a vacuum state.

From these facts, it can be seen that the vacuum-insulated double glazing panel to which the glass frit for encapsulation material of the present invention and the glass paste for encapsulation thereof is applied can obtain a encapsulating portion having high heat insulating properties and reliability. rice field. Furthermore, by using the glass frit for encapsulation material and the glass paste for encapsulation material of the present invention, the encapsulation temperature can be remarkably lowered, which greatly contributes to the productivity improvement of the vacuum heat insulating double glazing panel. Can be done.

The glass composition used as the sealing material was STA-1 shown in Table 1, the camp sealing glass was HS-1 shown in Table 3, and the temperature T ₁ was 290 ° C. In the same manner, a vacuum-insulated double glazing was produced.

The visual inspection, the helium leak test, the immersion test and the temperature cycle test were also carried out in the same manner as in Example 1. In all the tests, the same results as in Example 1 were obtained.

The glass composition used as the sealing material was STA-2 shown in Table 1, the camp sealing glass was HS-2 shown in Table 3, and the temperature T ₁ was 280 ° C. In the same manner, a vacuum-insulated double glazing was produced.

The visual inspection, the helium leak test, the immersion test and the temperature cycle test were also carried out in the same manner as in Example 1. In all the tests, the same results as in Example 1 were obtained.

The vacuum insulation multilayer layer is the same as in Example 3 except that the glass composition used as the sealing material is STA-3 shown in Table 1 and the glass for camping sealing is HS-3 shown in Table 3. Glass was made.

The visual inspection, the helium leak test, the immersion test and the temperature cycle test were also carried out in the same manner as in Example 1. In all the tests, the same results as in Example 1 were obtained.

The vacuum insulation multilayer layer is the same as in Example 3 except that the glass composition used as the sealing material is STA-4 shown in Table 1 and the glass for camping sealing is HS-4 shown in Table 3. Glass was made.

The visual inspection, the helium leak test, the immersion test and the temperature cycle test were also carried out in the same manner as in Example 1. In all the tests, the same results as in Example 1 were obtained.

As described above, from Examples 1 to 5, by providing the exhaust port at a position adjacent to the sealing material and sealing while exhausting the internal space, the exhaust port is closed by the sealing material while keeping the internal space in a vacuum state. It was confirmed that a double glazing having a structure in which the exhaust port is covered with a sealing portion can be manufactured.

Table 3 shows the compositions (HS-1 to HS-5) of the sealing glass for caps used in the above examples. Table 4 shows the results of each characteristic temperature.

The cap encapsulating glass has a higher Ag ₂ O content than the glass composition used as the encapsulating material. As a result, the cap sealing glass has a lower softening point than the glass composition used as the sealing material.

The above description can be summarized as follows.

As shown in Tables 1 and 3, the encapsulating glass and the encapsulating glass for the cap include V ₂ O ₅ , TeO ₂ and Ag ₂ O. The encapsulating glass has a lower Ag ₂ O content than the cap encapsulating glass.

The softening point of the sealing glass is 300 ° C. or lower. Further, the softening point of the sealing glass may be higher than the softening point of the sealing glass for the cap, and may be 250 ° C. or lower.

The softening point of the cap sealing glass is 250 ° C. or lower.

The softening point of the sealing glass and the sealing glass for the cap is preferably 120 ° C. or higher because the upper limit of the allowable temperature of the actual usage environment of the glass panel is 120 ° C.

The sealing glass has an Ag ₂ O content of 21 mol% or more and 27 mol% or less, preferably 22 mol% or more and 26 mol% or less.

The cap sealing glass has an Ag ₂ O content of 26 mol% or more and 32 mol% or less, preferably 27 mol% or more and 31 mol% or less.

It is desirable that the two glass plates are tempered glass.

It is desirable that at least a part of the cap and the sealing glass for the cap is embedded in the opening. In this case, the diameter of the cap is set to be smaller than the diameter of the opening, and a cap sealing glass is attached to the peripheral edge of the cap. If you push the cap in, the cap will be embedded in the opening.

Hereinafter, the glass panel manufacturing method and the manufacturing apparatus will be collectively described.

A method for manufacturing a glass panel includes two glass plates and a sealing portion sandwiched between the two glass plates, and a glass panel having an internal space surrounded by the two glass plates and the sealing portion. It is a manufacturing method and includes a step of supplying a cap and a sealing glass for a cap so as to close an opening provided in at least one of two glass plates. Here, the sealing portion includes a sealing glass. Further, the sealing glass for a cap has a lower softening point than the sealing glass.

It is desirable to further include a step of raising the temperature of the glass panel above the softening point of the sealing glass before closing the opening.

It is desirable to further include a step of evacuating the internal space before closing the opening.

The glass panel manufacturing apparatus includes two glass plates and a sealing portion sandwiched between the two glass plates, and the glass panel having an internal space surrounded by the two glass plates and the sealing portion. The manufacturing apparatus includes a mechanism for supplying a cap and a sealing glass for a cap so as to close an opening provided in at least one of two glass plates. Here, the sealing portion includes a sealing glass. Further, the sealing glass for a cap has a lower softening point than the sealing glass.

It is desirable to further include a heating portion that raises the temperature of the glass panel above the softening point of the sealing glass.

It is desirable to further include a vacuum pump that evacuates the interior space before closing the opening.

1: 1st glass substrate 2: 2nd glass substrate 3: Spacer 4: Sealing part 5: Exhaust port, 6: Heat ray reflecting film, 7: Sealing material, 8: Exhaust head, 9: Heating device, 10: Vacuum pump, 11, 12, 13: Emission gas component, 14: First internal space, 15: Second internal space, 16: Panel carry-in mechanism, 17: Tunnel type heating furnace, 18: Panel carry-out mechanism, 19: Clip, 20: Vacuum pump equipment, 21: Cap, 22: Cap encapsulation glass, 23: Arrow, 104: Encapsulation material.

Claims (14)

Two glass plates and
With a sealing portion sandwiched between these glass plates,
It has an internal space surrounded by the two glass plates and the sealing portion.
At least one of the two glass plates is provided with a cap for closing the opening provided in the glass plate and a sealing glass for the cap.
The sealing portion includes a sealing glass and contains.
The sealing glass for a cap is a glass panel having a lower softening point than the sealing glass. The glass panel according to claim 1, wherein the sealing portion is arranged on the peripheral edge portion of the two glass plates. The glass panel according to claim 1, wherein the internal space is in a vacuum state. The encapsulating glass and the cap encapsulating glass contain V ₂ O ₅ , TeO ₂ and Ag ₂ O.
The glass panel according to claim 1, wherein the sealing glass has a lower content of Ag ₂ O than the sealing glass for a cap. The softening point of the sealing glass is 300 ° C. or lower, and the temperature is 300 ° C. or lower.
The glass panel according to claim 1, wherein the softening point of the sealing glass for a cap is 120 ° C. or higher and 250 ° C. or lower. The glass panel according to claim 1, wherein the sealing glass for a cap has an Ag ₂ O content of 26 mol% or more and 32 mol% or less. The glass panel according to claim 1, wherein the two glass plates are tempered glass. The glass panel according to claim 1, wherein at least a part of the cap and the sealing glass for the cap is embedded in the opening. It is a method of manufacturing a glass panel having two glass plates and a sealing portion sandwiched between these glass plates, and having an internal space surrounded by the two glass plates and the sealing portion. hand,
A step of supplying a cap and a sealing glass for a cap so as to close an opening provided in at least one of the two glass plates is included.
The sealing portion includes a sealing glass and contains.
The sealing glass for a cap is a method for manufacturing a glass panel, which has a lower softening point than the sealing glass. The method for manufacturing a glass panel according to claim 9, further comprising a step of raising the temperature of the glass panel to a temperature equal to or higher than the softening point of the sealing glass before closing the opening. The method for manufacturing a glass panel according to claim 10, further comprising a step of evacuating the internal space before closing the opening. It is an apparatus for manufacturing a glass panel having two glass plates and a sealing portion sandwiched between these glass plates, and having an internal space surrounded by the two glass plates and the sealing portion. hand,
A mechanism for supplying a cap and a sealing glass for a cap so as to close an opening provided in at least one of the two glass plates is included.
The sealing portion includes a sealing glass and contains.
The cap sealing glass is a glass panel manufacturing apparatus having a softening point lower than that of the sealing glass. The glass panel manufacturing apparatus according to claim 12, further comprising a heating portion for raising the temperature of the glass panel to a temperature equal to or higher than the softening point of the sealing glass. 13. The glass panel manufacturing apparatus according to claim 13, further comprising a vacuum pump that evacuates the internal space before closing the opening.

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