Vacuum glass and preparation method thereof

Abstract

The present invention provides a vacuum glass and a preparation method thereof, which belongs to the technical field of energy-saving glass preparation. The vacuum glass provided by the present invention includes an internal vacuum glass component and an external protective component; the internal vacuum glass component includes two-way curved glass arranged opposite to each other, steel pressure plates arranged opposite to each other, and a barrier film wrapping the two-way curved glass and the steel pressure plates; the steel pressure plates are arranged around the two-way curved glass; the steel pressure plates are provided with grooves, and gaskets are provided at the connection between the grooves and the two-way curved glass; channels are provided between the grooves; steel strands pass through the channels of the two-way curved plates arranged opposite to each other and are fastened by anchors; a getter is provided in the internal vacuum layer of the two-way curved glass arranged opposite to each other. The vacuum glass provided by the present invention does not require the use of supporting point supporting glass, low-melting point glass sealing materials and edge sealing technology, and has excellent thermal barrier properties and sound insulation properties, and a long service life.

Description

Technical Field

[0001] The present invention relates to the technical field of energy-saving glass preparation, and in particular to vacuum glass and a preparation method thereof. Background Art

[0002] As my country's building energy-saving standards become increasingly stringent, the commercial production of large-area vacuum glass has become increasingly urgent, especially in the construction and promotion of "passive houses". The overall heat transfer coefficient of the window is proposed to be ≤0.8W / (m 2 k), taking into account the heat dissipation of the window frame, the heat transfer coefficient of the glass is required to be ≤0.6W / (m 2 k). As a new type of light-transmitting and heat-insulating material in the 21st century, vacuum glass is the leader in terms of its excellent sound insulation, heat preservation, visible light transmission and infrared light reflection properties.

[0003] Currently, the commercial production of vacuum glass suffers from several major bottlenecks: support points, sealing materials, and edge-sealing technology. Vacuum glass supports are mostly made of metal, making it difficult to evenly distribute the metal supports across a large glass panel. Furthermore, the supports cannot be made with completely consistent heights during actual production, and the support points are prone to displacement during transportation, resulting in unbalanced stress in certain areas of the glass. Vacuum glass typically uses low-melting-point glass, which is sealed around two sheets of glass. This places extremely high demands on the sealing material, which must be airtight, resistant to aging, and have an expansion coefficient consistent with that of the glass. Otherwise, it will be difficult to maintain the vacuum level of the glass during long-term use. Edge-sealing technology generally uses overall heating for heat treatment, which has the following disadvantages: overall heating consumes a large amount of heat energy; the heat treatment process can cause deformation of the glass, etc. Summary of the Invention

[0004] In view of this, the present invention provides a vacuum glass and a method for preparing the same. The vacuum glass provided by the present invention does not require support glass, low-melting-point glass sealing materials, or edge sealing technology, and has excellent thermal and sound insulation properties and a long service life.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a vacuum glass, comprising an internal vacuum glass assembly and an external protective assembly; the internal vacuum glass assembly comprises oppositely arranged two-way curved glass, two oppositely arranged steel pressure plates, and a barrier film wrapping the two-way curved glass and the steel pressure plates; the steel pressure plates are arranged around the two-way curved glass; the steel pressure plates are provided with grooves, and gaskets are provided at the connection between the grooves and the two-way curved glass; channels are provided between the grooves; steel strands pass through the channels of the oppositely arranged steel pressure plates and are fastened by anchors; and a getter is provided in the internal vacuum layer of the oppositely arranged two-way curved glass.

[0007] Preferably, the spacing between the grooves is 10 mm to 18 mm, and a width of 5 mm is left on the outside.

[0008] Preferably, the spacing between the channels is 100 mm to 200 mm, and the diameter is 5 mm to 9 mm.

[0009] Preferably, the diameter of the steel strand is φ5mm to φ9mm.

[0010] Preferably, one end of the steel strand is a cap, and the other end is a thread, and the length of the thread is 50 mm.

[0011] Preferably, the prestress of the steel strand is 1570 MPa, 1670 MPa, 1770 MPa or 1860 MPa.

[0012] Preferably, the two-way curved glass is soda-lime glass with a thickness of 3mm to 12mm, a long side length of 2110 to 5000mm, a short side length of 1270 to 3180mm, a long side glass curved surface central angle of 0.25 to 1.0°, and a short side glass curved surface central angle of 0.15 to 0.9°.

[0013] Preferably, the anchor is a high-hardness steel nut, and the internal thread of the anchor is consistent with the thread of the steel strand.

[0014] Preferably, the external protection assembly includes tempered glass and a plastic guard plate.

[0015] The present invention also provides a method for preparing the vacuum glass described in the above technical solution, comprising the following steps:

[0016] A gasket is laid in the groove of the steel pressure plate, and a steel strand is passed through the hole of the oppositely arranged steel pressure plate. After placing the two-way curved glass on the gasket, a getter is placed in the inner vacuum layer of the two-way curved glass, and an anchor is fastened. After applying tensile stress to the steel strand, a prestressed vacuum glass is obtained.

[0017] The prestressed vacuum glass is placed in a barrier vacuum bag, vacuumed and hot-pressed in sequence, and then a barrier film is applied to the prestressed vacuum glass;

[0018] After assembling the external protection components on the surface of the barrier film, the vacuum glass is obtained.

[0019] The present invention provides a vacuum glass and a preparation method, comprising an internal vacuum glass assembly and an external protective assembly; the internal vacuum glass assembly comprises opposing two-way curved glass, steel pressure plates disposed opposite each other, and a barrier film encapsulating the two-way curved glass and the steel pressure plates; the steel pressure plates are disposed around the four sides of the two-way curved glass; the steel pressure plates are provided with grooves, gaskets are provided at the junctions between the grooves and the two-way curved glass; holes are provided between the grooves; steel strands are passed through the holes of the opposing steel pressure plates and secured by anchors; and a getter is provided in the internal vacuum layer of the opposing two-way curved glass. The present invention applies prestress to the steel strands by passing the steel strands through the holes of the opposing steel pressure plates and securing them with anchors, thereby achieving a working stress. This allows the vacuum glass to sufficiently balance the compressive stress exerted on the vacuum glass by the external atmosphere, eliminating the need for support glass at supporting points, low-melting-point glass sealing materials, and edge sealing technology. The vacuum glass exhibits excellent thermal and sound insulation properties and a long service life. The results of the embodiment show that the heat transfer coefficient of the vacuum glass prepared by the present invention is 0.4-0.9W / m 2 k, sound insulation is 35-45dB, and visible light transmittance is 60-70%.

[0020] Furthermore, the preparation method of vacuum glass provided by the present invention avoids the use of support points, sealing materials and edge sealing technologies. By applying prestress to the steel strands to constrain the deformation of the vacuum glass under negative pressure, the processing of large-size vacuum glass becomes a reality, thereby solving the technical difficulties in the existing technology and the complex vacuum glass processing technology; at the same time, it reduces production costs and is suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Figure 1 A physical picture of the vacuum glass provided by the present invention;

[0023] Figure 2 This is a schematic diagram of the structure of the vacuum glass made in Example 1 of the present invention, wherein 1 is a plastic protective plate, 2 is tempered glass, 3 is a barrier film, 4 is two-way curved glass, 5 is a steel strand, 6 is a channel, 7 is an anchor, 8 is a gasket, 9 is a steel pressure plate, and 10 is a groove. DETAILED DESCRIPTION

[0024] The present invention provides a vacuum glass assembly, comprising an internal vacuum glass assembly and an external protective assembly; the internal vacuum glass assembly comprises opposing two-way curved glass, two opposing steel pressure plates, and a barrier film encapsulating the two-way curved glass and the steel pressure plates; the steel pressure plates are disposed around the four sides of the two-way curved glass; the steel pressure plates are provided with grooves, and gaskets are provided at the connection between the grooves and the two-way curved glass; channels are provided between the grooves; steel strands are passed through the channels of the opposing steel pressure plates and secured by anchors; and a getter is provided in the internal vacuum layer of the opposing two-way curved glass. The present invention applies prestress to the steel strands by passing the steel strands through the channels of the opposing steel pressure plates and securing them with anchors, thereby achieving a working stress. This allows the vacuum glass to sufficiently balance the compressive stress exerted on the vacuum glass by the external atmosphere, eliminating the need for supporting glass at supporting points, low-melting-point glass sealing materials, and edge-sealing technology. The vacuum glass exhibits excellent thermal and sound insulation properties and a long service life.

[0025] Figure 1 This is a physical picture of the vacuum glass provided by the present invention.

[0026] In the present invention, unless otherwise specified, the raw materials used are conventional commercial products in the art or are prepared by conventional methods in the art.

[0027] In the present invention, the bidirectional curved glass is preferably made of soda-lime glass, with a thickness of preferably 3 mm to 12 mm, more preferably 4 mm. The length of the long side is preferably 2110 mm to 5000 mm, more preferably 3000 mm, and the length of the short side is preferably 1270 mm to 3180 mm, more preferably 2000 mm. The central angle of the long side glass curvature is preferably 0.25 to 1.0°, more preferably 0.8°, and the central angle of the short side glass curvature is 0.15 to 0.9°, more preferably 0.7°. The glass used in the present invention has excellent chemical stability and mechanical strength, providing a mechanical performance foundation for processing large-scale vacuum glass.

[0028] In the present invention, the gasket is preferably made of a nitrile rubber gasket, a fluororubber gasket, a natural rubber gasket, a chloroprene rubber gasket, an EPDM gasket, or a silicone rubber gasket. In the present invention, the gasket is preferably of the same length as the long and short sides of the two-way curved glass, and preferably has the same width as the groove width. The thickness is preferably 1 mm to 3 mm.

[0029] In the present invention, the steel pressure plate is preferably made of high-carbon tool steel, high-carbon alloy steel, high-speed steel, or steel-bonded carbide. In the present invention, the steel pressure plate is preferably 10 mm to 20 mm thick, more preferably 11 mm thick, and has a length that is consistent with the long and wide sides of the two-way curved glass. The width is preferably 28 mm to 60 mm, more preferably 30 mm.

[0030] In the present invention, the width of the groove is preferably 4 mm to 16 mm, more preferably 5 mm, and the depth is preferably 3 mm to 5 mm. In the present invention, the spacing between the grooves is preferably 10 mm to 18 mm, more preferably 12 mm, with a width of 5 mm left on the outside. In the present invention, the spacing between the channels is preferably 100 mm to 200 mm, more preferably 120 mm, and the diameter is preferably 5 mm to 9 mm, more preferably 6 mm.

[0031] In the present invention, the diameter of the steel strand is preferably φ5mm to φ9mm, more preferably φ6mm, and the prestress is preferably 1570MPa, 1670MPa, 1770MPa, or 1860MPa. In the present invention, one end of the steel strand is preferably a cap, and the other end is preferably a threaded wire, and the length of the threaded wire is preferably 50mm.

[0032] In the present invention, the material of the anchor is preferably a high-hardness steel nut, and the internal thread of the anchor is preferably consistent with the thread of the steel strand.

[0033] In the present invention, the barrier film is preferably prepared from a barrier vacuum bag. In the present invention, the barrier vacuum bag is preferably prepared by the following steps: PE film, PA film, polyvinylidene chloride (PVDC) film and ethylene-vinyl alcohol random copolymer (EVOH) film are sprayed on the surface of the polyurethane glue in sequence, and then subjected to hot melt sealing treatment under a vacuum environment. In the present invention, the mass ratio of the PE film, PA film, polyvinylidene chloride film and ethylene-vinyl alcohol random copolymer film is preferably 1:0.5~0.8:0.6~0.8:0.6~0.8. The present invention has no special limitation on the operation mode of the spraying, and the spraying method well known to those skilled in the art can be adopted. The present invention has no special limitation on the specific operation of the hot melt sealing, and the hot melt sealing method well known to those skilled in the art can be adopted.

[0034] In the present invention, the getter is preferably prepared from one or more of a titanium-zirconium-vanadium getter, a zirconium-vanadium-iron getter, and a zirconium-cobalt-rare earth getter. In the present invention, the getter is preferably encapsulated by a thin metal material. In the present invention, the thin metal material encapsulation process is preferably prepared by compressing a barium-lithium alloy, a Pd-Co3O4 catalyst, and a calcium oxide desiccant into a metal aluminum foil shell.

[0035] In the present invention, the exterior protective assembly preferably includes tempered glass and a plastic protective plate. The tempered glass preferably has a thickness of 0.3 mm to 1.0 mm, more preferably 0.8 mm. The dimensions of its long and wide sides are preferably consistent with those of the two-way curved glass, which are not described in detail here. The present invention does not specifically limit the positional relationship between the tempered glass and the plastic protective plate; conventional positional relationships in the art may be employed.

[0036] In the present invention, the shape of the plastic guard plate is preferably a groove shape, the thickness is preferably 1 to 2 mm, the length is preferably consistent with the length of the steel pressure plate, the width is preferably 28 mm to 60 mm, and the length of the groove bottom edge is preferably 10 mm to 20 mm. In the present invention, the plastic guard plate is preferably prepared from the following components in parts by mass: 80 to 90 parts of resin, 10 to 15 parts of filler, 0.2 to 0.5 parts of stearic acid, 0.3 to 0.8 parts of calcium stearate, 0.2 to 0.3 parts of oxidized polyethylene wax, 4 to 6 parts of tribasic lead sulfate, 5 to 10 parts of chlorinated polyethylene (CPE) resin, and 1 to 2 parts of impact-modified acrylic ester (ACR) resin. In the present invention, the resin preferably includes one or more of polyvinyl chloride (PVC) resin, acrylonitrile-butadiene-styrene (ABS) resin, polyoxymethylene (POM) resin, polymethyl methacrylate (PMMA) resin, polycarbonate (PC) resin, polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin and polyphenylene ether (PPO) resin, and is further preferably PVC; the filler preferably includes one or more of talc, heavy calcium carbonate, light calcium carbonate, quartz sand, dolomite and wollastonite; the chlorine content of the CPE resin is preferably 36%.

[0037] The present invention also provides a method for preparing the vacuum glass described in the above technical solution, comprising the following steps:

[0038] A gasket is laid in the groove of the steel pressure plate, and a steel strand is passed through the hole of the oppositely arranged steel pressure plate. After placing the two-way curved glass on the gasket, a getter is placed in the inner vacuum layer of the two-way curved glass, and an anchor is fastened. After applying tensile stress to the steel strand, a prestressed vacuum glass is obtained.

[0039] The prestressed vacuum glass is placed in a barrier vacuum bag, vacuumed and hot-pressed in sequence, and then a barrier film is applied to the prestressed vacuum glass;

[0040] After assembling the external protection components on the surface of the barrier film, the vacuum glass is obtained.

[0041] In the present invention, gaskets are placed in the grooves of steel pressure plates, and steel strands are passed through the channels of the opposing steel pressure plates. After placing biaxially curved glass on the gaskets, a getter is placed in the internal vacuum layer of the biaxially curved glass, anchors are fastened, and tensile stress is applied to the steel strands to produce prestressed vacuum glass. In the present invention, the biaxially curved glass is preferably produced by a method comprising the following steps: hot pressing a glass blank and a carbide mold in a nitrogen atmosphere, followed by cooling, demolding, and sputtering a metal layer and an oxide layer to produce the biaxially curved glass. In the present invention, the hot pressing is preferably performed in a hot bending machine. In the present invention, the carbide mold is preferably made of a highly heat-resistant carbide. In the present invention, the hot pressing temperature is preferably 680-800°C, more preferably 750°C, and the heating rate to the hot pressing temperature is preferably 1-10°C / min, more preferably 5°C / min. The hot pressing time is not particularly limited, as long as it produces viscous glass. In the present invention, the cooling preferably includes a first cooling step and a second cooling step in sequence. The first cooling step preferably ends at a temperature of 530-560°C, and the cooling rate to the first cooling temperature is preferably 0.5-3°C / min, more preferably 2°C / min. The second cooling step is preferably performed using nitrogen. In the present invention, the second cooling step preferably ends at room temperature. The present invention reduces residual stress in a portion of the interior of the glass through two cooling steps.

[0042] In the present invention, the metal layer preferably includes one or more of a gold layer, a silver layer, a copper layer and a gold-silver-copper alloy layer. In the present invention, the oxide layer preferably includes one or more of an indium tin oxide layer, a titanium dioxide layer, a zirconium oxide layer, a tin oxide layer and an indium oxide layer. In the present invention, the thickness of the metal layer and the oxide layer are independently preferably 10 to 30 nm. The present invention has no special limitation on the specific operation of the sputtering, and a sputtering method familiar to those skilled in the art can be used. The present invention can effectively improve the ability of vacuum glass to block infrared heat conduction by sputtering the metal layer and the oxide layer. In the present invention, the temperature of the hot pressing sealing is preferably 160 to 180°C, and the time is preferably 2 to 5s. The present invention tightens the anchor so that the glass is sufficient to balance the compressive stress generated by the external atmosphere on the vacuum glass.

[0043] After the barrier film is applied, the present invention assembles an external protective component onto the surface of the barrier film to obtain the vacuum glass. The present invention preferably uses a laser beam to activate the getter, and then sequentially adheres the tempered glass and clamps the plastic protective plate onto the surface of the barrier film. The present invention does not specifically limit the specific method of application; any application method familiar to those skilled in the art can be employed. The present invention does not specifically limit the specific method of clamping; any clamping method familiar to those skilled in the art can be employed.

[0044] The vacuum glass and the preparation method provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0045] Example 1

[0046] 1) Using a hot bending machine to process glass, a soda-lime glass blank with a thickness of 3 mm, a long side dimension of 2110 mm, and a short side dimension of 1270 mm was placed in a heat-resistant carbide mold. The heating furnace was filled with nitrogen. The upper and lower heating plates heated the glass blank and the mold together to the molding temperature of 680°C at a heating rate of 10°C / min. Under the condition of a constant furnace temperature, the viscous glass was hot-pressed by closing the mold. The mold and the semi-finished glass were slowly cooled at a cooling rate of 3°C / min to the annealing point of 560°C to reduce residual stress in a part of the glass. Finally, cooling nitrogen was quickly filled to cool the formed glass and the mold to room temperature. The central angle of the curved surface of the glass in the longitudinal direction was 1.0°, and the central angle of the curved surface of the glass in the width direction was 0.9°.

[0047] 2) Select a glass surface and magnetron sputter a gold layer, and then sputter an indium tin oxide layer on the upper surface of the gold layer;

[0048] 3) Use silicone rubber gasket as gasket, the length is consistent with the length of the steel plate, the width is consistent with the width of the steel plate groove, and the thickness is 2mm;

[0049] 4) The steel pressure plate is made of high-carbon tool steel, with a thickness of 10mm. There are two steel pressure plates of 2110mm in length and two steel pressure plates of 1270mm in length. The width of the steel pressure plate is 28mm. The steel pressure plate has two grooves facing the glass surface for inlaying glass. The width is 4mm and the depth is 3mm. There is a 10mm gap between the two grooves and a 5mm gap on each side of the grooves. The hole spacing is 200mm and the hole diameter is 5mm.

[0050] 5) The steel wire is a high-strength prestressed steel wire of 1860MPa, with a diameter of φ5, a cap on one end and a 50mm thread on the other end;

[0051] 6) The anchor is a high-hardness steel nut with an internal thread consistent with the steel wire thread;

[0052] 7) The barrier vacuum bag is made of a composite of one layer each of PE, polyvinylidene chloride (PVDC), and ethylene-vinyl alcohol random copolymer (EVOH) barrier resin film. The mass ratio of PE film, PA film, polyvinylidene chloride film, and ethylene-vinyl alcohol random copolymer film is 1:0.5:0.6:0.6. The dimensions are consistent with the longitudinal and transverse dimensions of the glass. The bag is prepared by hot-melt welding in a vacuum environment to prepare a bag with three closed sides and one open end.

[0053] 8) Rubber gaskets are laid in the grooves of the steel pressure plate. The steel wire is passed through the steel pressure plate and fastened with anchors. A 3mm glass is placed in the grooves of the steel pressure plate, a getter is placed, and tensile stress is applied to the steel strands to reach the working stress, so that the glass can balance the compressive stress generated by the outside atmosphere on the glass.

[0054] 9) Place the glass with steel wire applied into a barrier vacuum bag, evacuate the bag and seal it with hot pressing. The laser generator emits a laser beam, which penetrates the glass and heats the encapsulated getter to unseal it. Finally, a tempered glass film is pasted on the outside of the vacuum glass.

[0055] The heat transfer coefficient, visible light transmittance and sound insulation of the obtained prestressed confined vacuum glass were tested, and the results are listed in Table 1.

[0056] Figure 1 This is a schematic structural diagram of the vacuum glass obtained in Example 1 of the present invention, wherein 1 is a plastic protective plate, 2 is tempered glass, 3 is a barrier film, 4 is a two-way curved glass, 5 is a steel strand, 6 is a channel, 7 is an anchor, 8 is a gasket, 9 is a steel pressure plate, and 10 is a groove.

[0057] Example 2

[0058] 1) Using a hot bending machine to process glass, a soda-lime glass blank with a thickness of 12 mm, a long side dimension of 5000 mm, and a short side dimension of 3180 mm was placed in a heat-resistant carbide mold. The heating furnace was filled with nitrogen. The upper and lower heating plates heated the glass blank and the mold together to the molding temperature of 800°C at a heating rate of 1°C / min. Under the condition of a constant furnace temperature, the viscous glass was hot-pressed by closing the mold. The mold and the semi-finished glass were slowly cooled at a cooling rate of 0.5°C / min to the annealing point of 550°C to reduce residual stress in a part of the glass. Finally, cooling nitrogen was quickly filled to cool the formed glass and the mold to room temperature. The central angle of the curved surface of the glass in the longitudinal direction was 0.25°, and the central angle of the curved surface of the glass in the width direction was 0.15°.

[0059] 2) magnetron sputtering a gold-silver-copper alloy layer on one side of glass, and sputtering an indium tin oxide layer on the upper surface of the gold-silver-copper alloy layer;

[0060] 3) Use silicone rubber gasket as gasket, the length is consistent with the length of steel pressure plate, the width is consistent with the width of steel pressure plate groove, and the thickness is 3mm.

[0061] 4) The steel pressure plate is made of high carbon tool steel with a thickness of 20mm. There are two steel pressure plates with a length of 5000mm and two steel pressure plates with a length of 3180mm. The width of the steel pressure plate is 54mm. Two grooves are opened on the steel pressure plate towards the glass surface for inlaying glass. The width is 13mm and the depth is 5mm. 18mm is left between the two grooves and 5mm is left on each side of the grooves. The hole spacing is 100mm and the hole diameter is 9mm.

[0062] 5) The steel wire is a high-strength prestressed steel wire of 1860MPa, with a diameter of φ9mm. One end of the steel wire is capped and the other end is threaded 50mm.

[0063] 6) The anchor is a high-hardness steel nut with an internal thread consistent with the steel wire thread.

[0064] 7) The barrier vacuum bag is composed of a composite of one layer of PA, PE, polyvinylidene chloride (PVDC), and ethylene-vinyl alcohol random copolymer (EVOH) barrier resin film. The mass ratio of PE film, PA film, polyvinylidene chloride film, and ethylene-vinyl alcohol random copolymer film is 1:0.8:0.8:0.8. The size is consistent with the longitudinal and transverse dimensions of the glass. The bag is prepared by hot-melt welding under a vacuum environment, with three sides closed and one end open.

[0065] 8) Place gaskets in the grooves of the steel platen, pass the steel wire through the platen and fasten it with anchors, place 3mm glass in the grooves of the platen, add a getter and apply tensile stress to make the steel strand reach the working stress, so that the glass can balance the compressive stress generated by the outside atmosphere on the glass;

[0066] 9) Place the glass with steel wire applied into a barrier vacuum bag, evacuate the bag and seal it with hot pressing. The laser generator emits a laser beam, which penetrates the glass and heats the encapsulated getter to unseal it. Finally, a tempered glass film is pasted on the outside of the vacuum glass.

[0067] The heat transfer coefficient, visible light transmittance, and sound insulation of the obtained prestressed confined vacuum glass were tested, and the results are listed in Table 1.

[0068] Example 3

[0069] 1) Using a hot bending machine to process glass, a soda-lime glass blank with a thickness of 3 mm, a long side dimension of 2110 mm, and a short side dimension of 1270 mm was placed in a heat-resistant carbide mold. The heating furnace was filled with nitrogen, and the upper and lower heating plates heated the glass blank and the mold together to the molding temperature of 700°C at a heating rate of 8°C / min. Under the condition of a constant furnace temperature, the viscous glass was hot-pressed by closing the mold. The mold and the semi-finished glass were slowly cooled at a cooling rate of 2°C / min to the annealing point of 550°C to reduce residual stress in a part of the glass. Finally, cooling nitrogen was quickly filled to cool the formed glass and the mold to room temperature. The central angle of the curved surface of the glass in the longitudinal direction was 0.5°, and the central angle of the curved surface of the glass in the width direction was 0.45°.

[0070] 2) Select a glass surface and magnetron sputter a silver layer, and then sputter an indium tin oxide layer on the upper surface of the silver layer;

[0071] 3) Use silicone rubber gasket as gasket, the length is consistent with the length of steel pressure plate, the width is consistent with the width of steel pressure plate groove, and the thickness is 2mm.

[0072] 4) The steel pressure plate is made of high carbon tool steel with a thickness of 10mm. There are two steel pressure plates with a length of 2110mm and two steel pressure plates with a length of 1270mm. The width of the steel pressure plate is 34mm. Two grooves are opened on the steel pressure plate towards the glass surface for inlaying glass. The width is 7mm and the depth is 3mm. 10mm is left between the two grooves and 5mm is left on each side of the grooves. The hole spacing is 100mm and the hole diameter is 5mm.

[0073] 5) The steel wire is high-strength prestressed steel wire 1570MPa, the diameter of the steel wire is φ5, one end of the steel wire is capped, and the other end has a 50mm thread.

[0074] 6) The anchor is a high-hardness steel nut with an internal thread consistent with the steel wire thread.

[0075] 7) The barrier vacuum bag is composed of a composite layer of PE, polyvinylidene chloride (PVDC), and ethylene-vinyl alcohol random copolymer (EVOH) barrier resin film. The mass ratio of PE film, PA film, polyvinylidene chloride film, and ethylene-vinyl alcohol random copolymer film is 1:0.6:0.7:0.7. The size is consistent with the longitudinal and transverse dimensions of the glass. The bag is prepared by hot-melt welding under a vacuum environment, with three sides closed and one end open.

[0076] 8) Place gaskets in the grooves of the steel platen, pass the steel wire through the platen, and fasten it with anchors. Place the glass with a large curved surface central angle and the glass with a small curved surface central angle in the grooves of the steel platen, add a getter, and apply tensile stress to make the steel strand reach the working stress, so that the glass can balance the compressive stress generated by the outside atmosphere on the glass.

[0077] 9) Place the glass with steel wire applied into a barrier vacuum bag, evacuate the bag and seal it with hot pressing. The laser generator emits a laser beam, which penetrates the glass and heats the encapsulated getter to unseal it. Finally, a tempered glass film is pasted on the outside of the vacuum glass.

[0078] The heat transfer coefficient, visible light transmittance and sound insulation of the obtained prestressed confined vacuum glass were tested, and the results are listed in Table 1.

[0079] Example 4

[0080] 1) Using a hot bending machine to process glass, a soda-lime glass blank with a thickness of 12 mm, a long side dimension of 5000 mm, and a short side dimension of 3180 mm was placed in a heat-resistant carbide mold. The heating furnace was filled with nitrogen. The upper and lower heating plates heated the glass blank and the mold together to the molding temperature of 790°C at a heating rate of 2°C / min. Under the condition of a constant furnace temperature, the viscous glass was hot-pressed by closing the mold. The mold and the semi-finished glass were slowly cooled at a cooling rate of 0.8°C / min to the annealing point of 540°C to reduce residual stress in a part of the glass. Finally, cooling nitrogen was quickly filled to cool the formed glass and the mold to room temperature. The central angle of the curved surface of the glass in the longitudinal direction was 1.0°, and the central angle of the curved surface of the glass in the width direction was 0.9°.

[0081] 2) magnetron sputtering a gold-silver-copper alloy layer on one side of glass, and sputtering an indium tin oxide layer on the upper surface of the gold-silver-copper alloy layer;

[0082] 3) Use silicone rubber gasket as gasket, the length is consistent with the length of steel pressure plate, the width is consistent with the width of steel pressure plate groove, and the thickness is 3mm.

[0083] 4) The steel pressure plate is made of high carbon tool steel with a thickness of 20mm. There are two steel pressure plates with a length of 5000mm and two steel pressure plates with a length of 3180mm. The width of the steel pressure plate is 60mm. Two grooves are opened on the steel pressure plate towards the glass surface for inlaying glass. The width is 16mm and the depth is 5mm. 18mm is left between the two grooves and 5mm is left on each side of the grooves. A hole is opened every 100mm along the longitudinal direction between the grooves, and the hole diameter is 9mm.

[0084] 5) The steel wire is a high-strength prestressed steel wire of 1570MPa, with a diameter of φ9mm. One end of the steel wire is capped and the other end is threaded 50mm.

[0085] 6) The anchor is a high-hardness steel nut with an internal thread consistent with the steel wire thread.

[0086] 7) The barrier vacuum bag is composed of a composite of one layer of PA, PE, polyvinylidene chloride (PVDC), and ethylene-vinyl alcohol random copolymer (EVOH) barrier resin film. The mass ratio of PE film, PA film, polyvinylidene chloride film, and ethylene-vinyl alcohol random copolymer film is 1:0.8:0.8:0.8. The size is consistent with the longitudinal and transverse dimensions of the glass. The bag is prepared by hot-melt welding under a vacuum environment, with three sides closed and one end open.

[0087] 8) Place gaskets in the grooves of the steel platen, pass the steel wire through the platen, and fasten it with anchors. Place the glass with a large curved surface central angle and the glass with a small curved surface central angle in the grooves of the steel platen, add a getter, and apply tensile stress to make the steel strand reach the working stress, so that the glass can balance the compressive stress generated by the outside atmosphere on the glass.

[0088] 9) Place the glass with steel wire applied into a barrier vacuum bag, evacuate the bag and seal it with hot pressing. The laser generator emits a laser beam, which penetrates the glass and heats the encapsulated getter to unseal it. Finally, a tempered glass film is pasted on the outside of the vacuum glass.

[0089] The heat transfer coefficient, visible light transmittance and sound insulation of the obtained prestressed confined vacuum glass were tested, and the results are listed in Table 1.

[0090] Table 1 Performance test results of prestressed confined vacuum glass obtained in Examples 1 to 4

[0091]

[0092] As shown in Table 1, the heat transfer coefficient, visible light transmittance and sound insulation of the prestressed vacuum glass provided by the present invention all show excellent performance. The heat transfer coefficient of the prestressed vacuum glass is 0.4-0.9 W / m 2 k, sound insulation is 35-45dB, and visible light transmittance is 60-70%.

[0093] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing vacuum glass, characterized in that: The steps are: A gasket is laid in the groove of the steel pressure plate, and a steel strand is passed through the hole of the oppositely arranged steel pressure plate. After placing the two-way curved glass on the gasket, a getter is placed in the inner vacuum layer of the two-way curved glass, and an anchor is fastened. After applying tensile stress to the steel strand, a prestressed vacuum glass is obtained. The prestressed vacuum glass is placed in a barrier vacuum bag, vacuumed and hot-pressed in sequence, and then a barrier film is applied to the prestressed vacuum glass; After assembling the external protective components on the surface of the barrier film, the vacuum glass is obtained; The two-way curved glass is prepared by a method comprising the following steps: hot pressing a glass blank and a carbide mold in a nitrogen atmosphere, followed by cooling, demolding, and spraying a metal layer and an oxide layer to obtain the two-way curved glass; The vacuum glass includes an internal vacuum glass component and an external protective component; the internal vacuum glass component includes oppositely arranged two-way curved glass, steel pressure plates arranged oppositely in pairs, and a barrier film wrapping the two-way curved glass and the steel pressure plates; the steel pressure plates are arranged around the two-way curved glass; the steel pressure plates are provided with grooves, and gaskets are provided at the connection between the grooves and the two-way curved glass; channels are provided between the grooves; steel strands pass through the channels of the oppositely arranged steel pressure plates and are fastened by anchors; a getter is provided in the internal vacuum layer of the oppositely arranged two-way curved glass.

2. The preparation method according to claim 1, characterized in that The spacing between the grooves is 10 mm to 18 mm, and a width of 5 mm is left on the outside.

3. The preparation method according to claim 1 or 2, characterized in that The spacing between the holes is 100 mm to 200 mm, and the diameter is 5 mm to 9 mm.

4. The preparation method according to claim 1, characterized in that The diameter of the steel strand is φ5mm to φ9mm.

5. The preparation method according to claim 1, characterized in that One end of the steel strand is a cap, and the other end is a thread, and the length of the thread is 50 mm.

6. The preparation method according to claim 1 or 5, characterized in that The prestressing force of the steel strand is 1570 MPa, 1670 MPa, 1770 MPa or 1860 MPa.

7. The preparation method according to claim 1, characterized in that The anchor is a high-hardness steel nut, and the internal thread of the anchor is consistent with the thread of the steel strand.

8. The preparation method according to claim 1, characterized in that The two-way curved glass is soda-lime glass with a thickness of 3mm to 12mm, a long side length of 2110 to 5000mm, a short side length of 1270 to 3180mm, a long side glass curved surface central angle of 0.25 to 1.0°, and a short side glass curved surface central angle of 0.15 to 0.9°.

9. The preparation method according to claim 1, characterized in that The external protection component includes tempered glass and a plastic guard plate.

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