Flexible micro-pillar for vacuum glass and vacuum glass

Abstract

The present invention provides flexible micro-pillars for vacuum glazing and vacuum glazing. The flexible micro-pillars for vacuum glazing comprise at least one glass fiber layer. The vacuum glazing of the present invention utilizes the flexible micro-pillars as microscopic pillars within the vacuum chamber. The present invention proposes an innovative method for significantly improving sound insulation by utilizing flexible micro-pillars made of glass fiber. The elasticity of the flexible micro-pillars also reduces the likelihood of glass breakage due to excessive stress at the point of contact with the micro-pillars when subjected to external impact.

Description

Technical Field

[0001] The invention relates to a flexible micro-pillar for vacuum glass and the vacuum glass, belonging to the technical field of vacuum glass. Background Art

[0002] Vacuum glass is composed of three components, including glass plates, peripheral packaging materials, and tiny pillars. It has a vacuum interlayer formed by at least two pieces of glass. Usually, the vacuum interlayer is encapsulated on all sides with a material that can remain airtight in a vacuum for a long time, such as low-melting-point encapsulating glass. An appropriate number of tiny pillars need to be arranged in the vacuum interlayer to support the glass plates on both sides to prevent them from being crushed or bent by atmospheric pressure. The thickness of the cavity in the vacuum interlayer is generally controlled below 0.3mm, because this thickness is approximately the lower limit for thermal convection in the cavity. A thickness lower than this can avoid thermal convection and help isolate heat transfer. The diameter of the tiny pillars is generally controlled between 0.2-0.5mm. When the diameter increases, it is easy to observe and cause visual impact. Therefore, the diameter size will be adjusted according to the application scenario of the vacuum glass. Vacuum glass has the following advantages: ① It has an extremely low heat transfer coefficient. Taking vacuum glass used in buildings as an example, it can be as low as 0.8W / m2·K, which is currently the product with the best thermal insulation effect among architectural glass; ② It is the product with the best sound insulation among transparent materials, and its weighted sound insulation can reach 35dB; ③ It is not easy to produce condensation even in high humidity environments.

[0003] When the gas inside vacuum glass is so rarefied that the pressure is less than 0.1 Pa, the heat conduction of the gas molecules can be ignored. If the surrounding packaging uses a frame structure to enhance the thermal barrier and is paired with glass panels coated with an anti-radiation film, the only factor that still contributes to heat conduction is the tiny pillars. Currently, most commercial vacuum glass uses stainless steel or ceramic pillars, both of which are good conductors of sound, greatly reducing the sound insulation function of vacuum glass. Furthermore, the heat transfer coefficient of the former is approximately 17 W / m·K, while the heat transfer coefficient of the latter is mostly above 2.7 W / m·K. Both are highly thermally conductive materials. When used in vacuum glass, they easily form heat bridges that conduct heat, significantly reducing the insulation effect of the vacuum glass.

[0004] Typical existing technologies such as Figure 1 As shown, the main function of the tiny pillars is to support the vacuum layer structure and resist atmospheric pressure, but they also form a shortcoming for the two most important functions of vacuum glass: heat insulation and sound insulation. The tiny pillars themselves form thermal bridges and sound bridges on both sides of the vacuum layer, reducing the heat insulation and sound insulation efficiency of the vacuum glass.

[0005] In addition, the materials of most micro-pillars are made of relatively strong materials. The most common materials are glass, ceramics, stainless steel, etc. The position where the micro-pillar contacts the glass plate in the vacuum layer is the stress concentration point that bears the atmospheric pressure. If the material strength of the micro-pillar itself is not enough and the hardness is weaker than the glass plate, it will be crushed because it cannot withstand the atmospheric pressure, such as glass beads or glass micro-pillars; if the micro-pillar itself is strong enough and tough, it will deform when subjected to 1 atmosphere of pressure, such as stainless steel beads and micro-pillars. The specific phenomenon is that the micro-pillar is flattened by the glass plate; if the material of the micro-pillar is too hard, such as certain super-hard ceramics (silicon carbide, silicon nitride, etc.) or high-hardness carbon steel and tungsten steel, the glass at the contact position between the glass plate and the micro-pillar will be scratched and worn at best, and cracks may appear at worst.

[0006] Even though certain ceramic and metal materials can be used as tiny pillars and do not deform, shatter, scratch, or crack the glass surface, these hard materials, whether solid, hollow, or ring-shaped, still have three drawbacks for the overall vacuum glass: ① They conduct heat well, making them a good thermal bridge; ② They easily conduct sound waves, making them a good acoustic bridge; and ③ When impacted by external forces, the glass sheet will instinctively deform to adapt. However, the hard tiny pillars themselves lack elasticity and have limited ability to deform at the point of contact with the glass, potentially causing stress concentration at the contact point. If this exceeds the strength of the glass at that point, it will still cause the glass to break. Therefore, the tiny pillars themselves need to maintain a certain strength to support the glass while also having sufficient elasticity to avoid excessive stress accumulation at the point of contact with the glass. Summary of the Invention

[0007] In order to solve the above technical problems, the purpose of the present invention is to provide a tiny pillar for vacuum glass, which is made of glass fiber material and can provide good sound insulation effect.

[0008] Another object of the present invention is to provide vacuum glass using the above-mentioned micro-pillars.

[0009] To achieve the above object, the present invention proposes using a glass fiber layer in the flexible micro-pillars of vacuum glass.

[0010] First, the present invention provides a flexible micro-pillar for vacuum glass, wherein the flexible micro-pillar has at least one glass fiber layer.

[0011] According to a specific embodiment of the present invention, preferably, the flexible micro-pillar has a composite structure consisting of two or more glass fiber layers.

[0012] According to a specific embodiment of the present invention, preferably, in the flexible micro-pillar, the thickness of the glass fiber layer is 0.1 mm to 3.0 mm.

[0013] According to a specific embodiment of the present invention, preferably, in the above-mentioned flexible micropillar, the thickness of the metal layer or alloy layer is less than 0.3 mm, more preferably 0.01 mm to 0.3 mm.

[0014] According to a specific embodiment of the present invention, preferably, the diameter of the flexible micro-pillar is 0.2 mm-2.0 mm; preferably 0.2 mm-0.5 mm.

[0015] According to a specific embodiment of the present invention, preferably, the thermal conductivity of the flexible micropillar is ≤1 W / m·K (25° C.).

[0016] According to a specific embodiment of the present invention, preferably, in the above-mentioned flexible micro-pillar, the glass fiber layer is made of ultra-fine glass fibers.

[0017] According to a specific embodiment of the present invention, preferably, in the flexible micro-pillar, the thermal conductivity of the glass fiber layer is ≤0.03 W / m·K (25° C.).

[0018] According to a specific embodiment of the present invention, preferably, in the above-mentioned flexible micro-pillar, the specific surface area of ​​the glass fiber layer is 700-800m 2 / g.

[0019] According to a specific embodiment of the present invention, preferably, in the above-mentioned flexible micro-pillar, the material of the metal layer includes one of aluminum, copper, iron, tin and zinc.

[0020] According to a specific embodiment of the present invention, preferably, in the above-mentioned flexible micro-pillar, the material of the alloy layer includes an alloy of two or more elements selected from aluminum, copper, iron, tin, and zinc.

[0021] The present invention also provides a vacuum glass, which uses the flexible micro-pillars as micro-pillars of the vacuum cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of vacuum glass structure and heat transfer.

[0023] Figure 2A and Figure 2B The microstructure inside the aerogel.

[0024] Figure 3 Schematic diagram of the flexible micro-pillar structure.

[0025] Figure 4This is the relationship curve between the thermal conductivity k value of the flexible micro-pillar and the thermal conductivity U value of the vacuum glass.

[0026] Figure 5A and Figure 5B These are the flexible micro-pillars produced after die stamping, among which, Figure 5A is the front view, Figure 5B It is a side view. DETAILED DESCRIPTION

[0027] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be understood as limiting the scope of implementation of the present invention.

[0028] An embodiment of one aspect of the present invention relates to a flexible micro-pillar for vacuum glass, wherein the flexible micro-pillar has at least one glass fiber layer.

[0029] The present invention uses a glass fiber layer (or glass fiber cloth) composed of glass fibers. This glass fiber layer has properties similar to aerogel and can be made to a thickness between 0.3-2.0 mm. It has ultra-light, heat-insulating, fire-resistant, shock-absorbing, flexible and other properties, and is particularly suitable for thermal insulation in narrow spaces.

[0030] In a specific embodiment of the present invention, the glass fiber layer can be made of ultrafine glass fibers. The material of the ultrafine glass fibers can be one or a combination of two or more of the silicate series glasses such as aluminosilicate glass, boroaluminosilicate glass, soda-lime glass, borosilicate glass and quartz glass. As long as the glass fibers are made of silicate glass, as long as the fibers are fine enough, they can be blended into glass fiber cloth to be used as the glass fiber layer of the present invention, and can exhibit strong elasticity and heat insulation effects. The fiber surface can be treated with hydrophobicity (the hydrophobic treatment can be carried out in a conventional manner). The sheet material composed of such ultrafine glass fibers is also a micro-nano material with very good heat insulation and sound absorption performance. Its microstructure can be referred to. Figure 2A and Figure 2B This micro-nano fiber structure can be formed into large-area sheets similar to paper or cloth, which can be manufactured in a roll-to-roll manner. The formed sheet has good softness and toughness. It can be greatly compressed without breaking when subjected to external pressure. After the external force is removed, it can return to its original shape due to the elasticity of the glass fiber. The material microstructure inside the glass fiber layer is mainly composed of air and microfibers (such as Figure 2A and Figure 2B As shown, the present invention uses a glass fiber layer as a component of a flexible micro-pillar dedicated to vacuum glass. With the help of this microstructure of the glass fiber layer, the glass fiber layer is beneficial for heat insulation and sound wave absorption, while providing elasticity and toughness when subjected to external force impact. Some physical parameters of the glass fiber layer are shown in Table 1 below:

[0031] Table 1

[0032]

[0033] In a specific embodiment of the present invention, the flexible micro-pillar preferably has a composite structure consisting of two or more glass fiber layers. Figure 3 As shown, by gluing and stacking glass fiber layers, a composite structure consisting of multiple glass fiber layers can be formed. The ultrafine glass fiber layer has a micro-nano mesh pore structure and is a good thermal insulation material.

[0034] As for the sound insulation function, although the ultra-fine glass fiber layer can be regarded as an excellent sound-absorbing material, the sound-absorbing material does not have the ability to reflect sound waves and is usually not a good sound insulation material. Vacuum itself is the best state of heat insulation and sound insulation. The transmission of heat or sound waves (vibration waves) depends on the medium. These flexible micro-pillars are placed in the vacuum layer in an environment with almost no air molecules. The only medium that can serve as a medium for the transmission of heat and sound energy is glass fiber, and the continuity of glass fiber (molding direction) is parallel to the glass plate, which means that most heat and sound energy are transmitted through the continuous surface of the glass fiber (parallel to the glass surface). A small amount of energy will be transmitted between the layers of the glass fiber layer (perpendicular to the glass plate), so it has a breaking bridge effect, and the heat insulation and sound insulation are similar. However, the wavelength of sound waves is relatively large, especially low-frequency sound, and the thickness of the vacuum layer is very thin, which is not conducive to sound insulation. Therefore, the flexible micro-pillars of the present invention are composited with metal layers, alloy layers and glass fiber layers, and metal layers / alloy layers are sandwiched between the glass fiber layers. The metal layers and alloy layers are arranged between the glass fiber layers as sound reflection layers. The sound can be repeatedly reflected between the glass plate (high-density medium) of the vacuum glass and the metal layers and alloy layers, which is equivalent to increasing the travel distance of sound insulation (sound absorption). During the reflection process, the sound is gradually absorbed by the mesh pore structure of the ultra-fine glass fiber layer, thereby improving the overall sound insulation effect, so that the obtained flexible micro-pillars have good sound insulation function.

[0035] Since the ultra-fine glass fiber layer itself is composed of micron-sized short glass fibers, when it is made into flexible micro-pillars and applied to vacuum glass, its weaving direction is parallel to the glass plate, that is, perpendicular to the setting direction of the flexible micro-pillars. Therefore, the direction of these layered fibers acts as a bridge for heat and sound transmission. This weaving method itself has the effect of blocking heat and sound waves. At the same time, this fiber weaving method also makes the flexible micro-pillars have quite good compressibility. When the flexible micro-pillars are arranged on the glass plate, such as Figure 3As shown, if its original height is h, after evacuation, it will bear the pressure of the glass plates on both sides. All micro-pillars and the surrounding packaging wall of the vacuum glass will jointly bear the pressure of one atmosphere of air. At this time, the micro-pillars composed of multiple layers of ultra-fine glass fiber cloth will be squeezed. If its height is compressed to h', depending on the different thicknesses and combinations, h' is usually ≤ 0.6h. However, even when subjected to external pressure, the flexible micro-pillars still retain their elasticity. Because the interior of the ultra-fine glass fiber layer is composed of countless long and short fibers interwoven, it still retains its toughness even when subjected to external pressure. Therefore, when the vacuum glass is hit by an external force, the glass plate itself can elastically deform with the external force and will not be restricted by the flexible micro-pillars made of the ultra-fine glass fiber layer. These flexible micro-pillars can help absorb some of the external force like a spring, but they have their own flexible elasticity so they will not cause scratches or cracks on the surface of the glass plate.

[0036] In one embodiment of the present invention, the flexible micropillar comprises a composite structure consisting of at least two fiberglass layers and at least one metal layer and / or alloy layer, wherein the metal layer and / or alloy layer is positioned between the two fiberglass layers. When the total number of metal and alloy layers is two or more, each metal layer and alloy layer may be spaced apart between different fiberglass layers.

[0037] In a specific embodiment of the present invention, the flexible micropillar has a composite structure consisting of at least three glass fiber layers and at least two metal layers and / or alloy layers, wherein the metal layers and / or alloy layers are spaced between the glass fiber layers.

[0038] In a specific embodiment of the present invention, the material of the metal layer includes one of aluminum, copper, iron, tin, and zinc; the material of the alloy layer includes an alloy of two or more elements among aluminum, copper, iron, tin, and zinc, wherein the alloy includes stainless steel.

[0039] In a specific embodiment of the present invention, the thickness of the glass fiber layer adopted by the flexible micro-pillar of the present invention can be 0.1mm to 3.0mm, preferably 1.0mm-3.0mm. Specifically, the thickness of the glass fiber layer can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm m, or a numerical range composed of the above specific thickness values ​​as endpoints, such as 0.2mm to 2.9mm, 0.3mm to 2.8mm, 0.4mm to 2.7mm, 0.5mm to 2.6mm, 0.6mm to 2.5mm, 0.7mm to 2.4mm, 0.8mm to 2.3mm, 0.9mm to 2.2mm, 1.0mm to 2.1mm, 1.1mm to 2.0mm, 1.2mm to 1.9mm, 1.3mm to 1.8mm, 1.4mm to 1.7mm, 1.5mm to 1.6mm, etc.

[0040] In one embodiment of the present invention, the specific surface area of ​​the glass fiber layer is 700-800 m 2 / g. Specifically, the specific surface area of ​​the glass fiber layer can be 700m 2 / g、710m 2 / g、720m 2 / g、730m 2 / g、740m 2 / g、750m 2 / g、760m 2 / g、770m 2 / g、780m 2 / g、790m 2 / g、800m 2 / g, or a numerical range consisting of the above specific thickness values ​​as endpoints, for example: 710-790m 2 / g, 720-780m 2 / g, 730-770m 2 / g, 740-760m 2 / g, etc.

[0041] In a specific embodiment of the present invention, the thickness of the metal layer or alloy layer used in the flexible micropillar having a composite structure is less than 0.3 mm, preferably 0.01 mm to 0.3 mm. Specifically, the thickness of the metal layer or alloy layer can be 0.3 mm, 0.2 mm, 0.1 mm, 0.01 mm, or a numerical range consisting of the above specific thickness values ​​as endpoints, such as 0.2 mm to 0.3 mm, 0.1 mm to 0.3 mm, 0.1 mm to 0.2 mm, 0.01 mm to 0.1 mm, 0.01 mm to 0.2 mm, etc.

[0042] In a specific embodiment of the present invention, the diameter of the flexible micropillar is 0.2mm-2.0mm; preferably 0.2mm-0.5mm. Specifically, the diameter of the flexible micropillar can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, or a numerical range composed of the above specific thickness values ​​as endpoints, such as 0.3mm to 0.9mm, 0.4mm to 1.8mm, 0.5mm to 1.7mm, 0.6mm to 1.6mm, 0.7mm to 1.5mm, 0.8mm to 1.4mm, 0.9mm to 1.3mm, 1.0mm to 1.2mm, etc.

[0043] In a specific embodiment of the present invention, the thermal conductivity of the flexible micropillar is ≤1.0 W / m·K (25°C); preferably, the thermal conductivity of the flexible micropillar is ≤0.25 W / m·K (25°C). Specifically, the thermal conductivity of the flexible micropillar can be 0.05W / m·K (25°C), 0.1W / m·K (25°C), 0.15W / m·K (25°C), 0.2W / m·K (25°C), 0.25W / m·K (25°C), 0.3W / m·K (25°C), 0.35W / m·K (25°C), 0.4W / m·K (25°C), 0.45W / m·K (25°C), 0.5W / m·K (25°C), 0.55W / m·K (25°C), 0.6W / m·K (25°C), 0.65W / m·K (25°C), 0.7W / m·K (25°C), 0.75W / m·K (25°C), 0.8W / m·K (25°C), 0.9W / m·K (25°C), 0.10 0.05-1.0W / m·K(25℃), 0.1-0.95W / m·K(25℃), 0.15-0.9W / m·K(25℃), 0.2-0.85W / m·K(25℃), 0.25-0.8W / m·K(25℃), 0.3-0.75W / m·K(25℃), 0.4-0.7W / m·K(25℃), 0.45-0.65W / m·K(25℃), 0.5-0.6W / m·K(25℃), etc.

[0044] In a specific embodiment of the present invention, the thermal conductivity of the glass fiber layer is ≤0.03 W / m·K (25°C). Specifically, the thermal conductivity of the glass fiber layer can be 0.01 W / m·K (25°C), 0.02 W / m·K (25°C), 0.03 W / m·K (25°C), or a numerical range consisting of endpoints of the above specific thickness values, for example, 0.01-0.03 W / m·K (25°C), 0.01-0.02 W / m·K (25°C), 0.02-0.03 W / m·K (25°C), etc.

[0045] Heat conduction in vacuum glazing occurs through four pathways: radiation, heat transfer through micropillars, heat transfer through trapped gases, and heat transfer through the surrounding seal. The thermal bridges formed by micropillars contribute the most to heat transfer, significantly reducing the inherently high thermal insulation properties of vacuum glazing. The following mathematical analysis focuses solely on heat conduction through micropillars in vacuum glazing.

[0046] Citing the experimentally verified mathematical model in the reference (Xu Wei, Building Energy Conservation, Vol. 42, No. 286, p. 25-30 (2014). Doi: 10.3969 / j.issn.1673-7237.2014.12.007), the heat transfer mathematical formula for cylindrical micro-pillars can be expressed as follows:

[0047]

[0048] Among them, C pillars is the thermal conductivity of the flexible micropillar, in W / (m 2 ·K), k g is the thermal conductivity of glass, the recommended value is 1.0 W / m·K; h is the micropillar height (m); a is the micropillar radius (m); b is the micropillar spacing (m); k pillar is the thermal conductivity of the micropillar material, in W / m·K.

[0049] Calculation Example 1:

[0050] Stainless steel micro pillar: k stainless steel =17W / (m·K)

[0051] Thermal conductivity of glass: k g =1W / (m·K)

[0052] a=0.25mm, b=40mm, h=0.15mm

[0053] According to the above formula, we can get: C pillars =0.306W / (m·K).

[0054] Calculation Example 2:

[0055] Flexible micro-pillars of the present invention: k soft pillar =0.03W / (m·K)

[0056] Thermal conductivity of glass: k g =1W / (m·K)

[0057] a=0.25mm, b=40mm, h=0.15mm

[0058] According to the above formula, we can get: C pillars =0.023W / (m·K).

[0059] Compared with stainless steel micro-pillars, the use of flexible micro-pillars can reduce heat transfer by 92.6%.

[0060] Figure 4The curve shown in the figure represents the relationship between the thermal conductivity k value of the micro-pillars and the thermal conductivity U value of the vacuum glass. The two sheets of glass that make up the vacuum layer are 4mm thick soda-lime glass, sealed on all four sides with a 10mm edge width. One of the glass surfaces inside the vacuum layer has a radiation-resistant coating (Low-E coating) using triple silver coating with a hemispherical emissivity of 0.015. The gas pressure inside the vacuum layer is 0.01Pa. The micro-pillars have a diameter of 5mm, a spacing of 40mm, and a height of 0.15mm. Experimental data and mathematical simulation curves show that when the above conditions are fixed, as the thermal conductivity k value of the micro-pillars decreases, for example, from a stainless steel micro-pillar with a k value of 17W / m·K to a ceramic micro-pillar with a k value of 2.7W / m·K, and then to an ultra-fine glass fiber cloth with a k value of 0.03W / m·K, the thermal conductivity of the vacuum glass will gradually decrease from about 0.9W / m·K. 2 K is reduced to 0.6W / m 2 K, a drop of 27%.

[0061] According to the reference (RE Collins and TM Simko, Solar Energy, Vol. 62, No. 3, pp. 189-213 (1998).), the static compressive strength P that the micropillar needs to withstand can be calculated as follows:

[0062]

[0063] In the above formula, P atm is atmospheric pressure. If the configuration in Example 1 is used, the static compressive strength P of each micro-pillar will be as high as 8×10 3 P atm , which is close to 1GPa of pressure. Furthermore, if the height of the micro-pillars in the vacuum layer is slightly different, whether due to the height difference of the micro-pillars themselves or the process error when placing them, the micro-pillars actually supporting the glass plate will be subjected to greater pressure. The yield strength of stainless steel is about 2×10 8 Pa, so if stainless steel microbeads (spherical particles) are used as tiny pillars, the strength of the contact point between the microbeads and the glass plate is not enough to support atmospheric pressure, and they will deform into a drum shape after being compressed. Therefore, in the vacuum glass currently sold on the market, if stainless steel is used as the pillar material, it will be in a drum or ring shape. The main reason is to increase the contact area with the glass plate and avoid point-like contact pressure. Doing so can protect the pillar material from being subjected to pressure below the material's fracture or deformation strength, and at the same time avoid pressure concentration at one point (or a very small area). Excessive pressure concentration also increases the probability of the glass plate itself breaking. The fracture strength of general soda-lime glass is about 8.9×10 7A characteristic of rigid materials is that when external forces exceed their material strength, they fracture, rather than deforming like metals. Therefore, glass microbeads are difficult to use as support materials in vacuum glazing. Porous glass beads are even weaker, making their application even more difficult. Some ceramics and steel alloys, such as but not limited to alumina, zirconia, and tungsten steel, have fracture strengths exceeding 1 GPa and are extremely rigid. Using microbeads made from these materials as support materials can result in the support remaining intact, but the glass sheet will fracture at the contact point. Therefore, microbeads must be formed in cylindrical, drum-shaped, or ring-shaped shapes to increase the contact area. While these materials can function as support materials with increased contact area, they lack elasticity. When the glass sheet is subjected to external vibration or impact, while it could otherwise dissipate the force by bending overall, the rigid microbeads confine the force, concentrating it at the contact point between the glass and the microbeads. This deformation is particularly pronounced at the edges of these contact points, and if the deformation exceeds the glass's strength, the glass will fracture at that point. The present invention uses a glass fiber layer to make flexible micro-pillars, which can replace the existing hard micro-pillars. The flexible micro-pillars themselves will not be damaged while providing support force. They can also cooperate with the deformation of the glass when it is subjected to external force to avoid glass breakage, and can well solve the problems existing in the existing micro-pillars.

[0064] In a specific embodiment of the present invention, the cross-section of the flexible micropillar can be any suitable shape, such as a circle, an ellipse, a rectangle, a triangle, a polygon with more than five sides, or a ring; wherein the ring can include a circular ring, a square ring, a triangular ring, a polygonal ring, or an irregular ring with a hollow part and an outer periphery of different shapes.

[0065] In a specific embodiment of the present invention, the flexible micro-pillar is in the shape of a trapezoid or a column, with flat surfaces at both ends for contact with the glass plate of the vacuum glass. The trapezoid can include a frustum, an elliptical cone, a prism or an annular cone; the column can include a cylindrical, an elliptical cylinder, a rectangular column, a prism or an annular column. The above-mentioned prism can include a triangular prism, a quadrangular cone, a polygonal cone with more than five edges; the above-mentioned annular cone can include a circular annular cone, a square annular cone or a polygonal annular cone; the above-mentioned prism includes a triangular prism, a quadrangular cone, a polygonal cone with more than five edges; the above-mentioned annular column includes a circular annular column, a square annular column or a polygonal annular prism. Moreover, the flexible micro-pillar of the present invention can be a trapezoid or column with irregular side surfaces, such as a drum shape.

[0066] The flexible micro-pillars of the present invention are elastic and can be compressed, and the amount of compression is greater than that of other materials currently used as micro-pillars (stainless steel, ceramics), which can allow the micro-pillars to have a larger elastic deformation. The flexible micro-pillars of the present invention can still effectively support the glass plate against atmospheric pressure after compression. Furthermore, they can also cooperate with the deformation of the glass plate when the glass plate is subjected to external force, so as to protect the glass plate and make it less likely to break at the support point. Preferably, the height of the flexible micro-pillars of the present invention under compression of 1 atmosphere of pressure is not less than 0.10mm, preferably 0.15-0.5mm, and more preferably 0.15-0.25mm.

[0067] Another aspect of the present invention relates to a vacuum glass that uses the flexible micro-pillars provided by the present invention as tiny pillars in a vacuum cavity. The vacuum glass comprises at least two glass plates, a vacuum cavity is formed between the two glass plates, and the flexible micro-pillars are distributed in the vacuum cavity.

[0068] In a specific embodiment of the present invention, the thermal conductivity of the flexible micropillar satisfies:

[0069]

[0070] In the above formula, C pillars is the thermal conductivity of the flexible micropillar, in W / (m 2 ·K), k pillar is the thermal conductivity of the flexible micropillar, in W / (m·K), k g is the thermal conductivity of glass, in W / (m·K), a is the radius of the flexible micropillar, in mm, b is the spacing between the flexible micropillars, in mm, and h is the equilibrium height of the flexible micropillar after compression, in mm.

[0071] In a specific embodiment of the present invention, in the vacuum glass, the spacing distance between the flexible micro pillars is not less than 30 mm, preferably 40-60 mm.

[0072] In a specific embodiment of the present invention, in the vacuum glass, the height of the vacuum cavity is less than 0.3 mm, preferably 0.15-0.25 mm.

[0073] The present invention proposes an innovative method, using flexible micro-pillars made of glass fiber to greatly improve the sound insulation effect. At the same time, the elastic effect of the flexible pillars can reduce the probability of glass breakage caused by excessive stress at the contact point with the tiny pillars when the glass is subjected to external impact.

[0074] The main components of the glass fiber used in the present invention are generally aluminum oxide and silicon oxide, which are melted at a temperature above 1600°C to form short fibers with a diameter of less than 10 microns, and then rolled into glass fiber cloth through a special process.

[0075] The following examples are used to specifically illustrate the method for manufacturing the flexible micro-pillars, but the technical solutions of the present invention are not limited thereto:

[0076] Step 1: Glass fiber cloth can be purchased from Jingning Technology (Beijing) Co., Ltd., whose material contains silicon oxide ≥ 60% and aluminum oxide ≥ 35%; the product name is: aerogel insulation cloth; width 600mm (roll), thickness 0.4mm, white and translucent, and thermal conductivity coefficient at room temperature of 25°C is 0.03W / m·K.

[0077] Step 2: When subjected to 1 atmosphere of pressure, the product's thickness elastically decreases by approximately 60%. The vacuum layer height is set at 0.4mm. Two pieces of 0.4mm thick fiberglass cloth are used, sandwiched with an 80μm thick metal foil (which can be, but is not limited to, aluminum foil, copper foil, etc.). The total initial thickness of the three is 0.88mm. When the vacuum is reduced to 0.01Pa, the total thickness decreases to 0.40mm. The design of flexible support structures and starting thicknesses for vacuum layers of different heights can be similarly deduced.

[0078] Step 3: After gluing the above three-layer or multi-layer structure, place the finished product in a 120°C vacuum oven to exhaust, and then use a punch press and appropriate molds to make micro-pillars with diameters ranging from 0.3-1.0mm, and store the prepared micro-pillars for future use. Figure 5A and Figure 5B They are the front view and side view of the flexible support after die forming, where: Figure 5B The curve in the figure represents the shape measured in the visible area of ​​the optical microscope. Figure 5A and Figure 5B It can be seen that the appearance of the circular pillar under optical measurement is circular, although it is not a perfect circle, but it can be determined that the flexible pillar is cylindrical.

[0079] Sound insulation test

[0080] The multi-layer structure of the flexible micro-pillar provided in the embodiment includes a fiber cloth composed of ultra-fine glass fibers. 80% of the volume of the fiber cloth is air. When placed in a vacuum layer, the original air portion becomes a vacuum. The vacuum can reduce thermal conductivity and sound insulation. At the same time, the fiber cloth is an open porous material. This material itself has good sound absorption ability. At least one layer of metal foil or alloy foil is sandwiched between two or more layers of fiber cloth. Since the metal foil and alloy foil themselves are dense materials, they have relatively good sound wave reflection capabilities. Therefore, when external sound waves are transmitted to the first layer of fiber cloth through the first layer of glass plate, part of the sound waves will be The vacuum inside the fiberglass cloth is a barrier, and another part of the sound waves will be absorbed by the glass fiber, and another part of the sound waves can continue to be transmitted through the glass fiber; when the sound waves that continue to be transmitted reach the metal foil / alloy foil, a part of them will be reflected by the metal foil / alloy foil, and the reflected waves will return to the first layer of glass plate through the glass fiber, and then a part of the reflected sound waves will be absorbed by the glass plate or transmitted outward, and a small part will be reflected back to the glass fiber through the surface of the glass plate. This reflection process will be repeated, and in the process of repeated reflection, the sound waves will gradually be absorbed by the sound-absorbing function of the glass fiber. Therefore, a better sound insulation effect can be achieved.

[0081] In addition to the aforementioned reflections, some sound waves reaching the metal / alloy foil will penetrate the foil and reach the second layer of fiberglass. While the foil itself will absorb some sound waves, the absorption is minimal because metals and alloys are relatively good sound reflectors and lack significant sound absorption. Similarly, sound waves reaching the second layer of fiberglass have already been attenuated by the first layer. Within the second layer, repeated reflections and absorption between the metal / alloy foil and the second glass sheet will also occur, ultimately resulting in only a residual portion of the sound waves reaching the outer side of the second glass sheet.

[0082] According to the national standard GB-T 18696.1-2004, sound insulation tests were conducted on insulating glass and vacuum glazing using various micropillars. The micropillars were made of stainless steel microbeads, hollow glass microbeads, solid glass microbeads, porous glass microbeads, and ultrafine glass fiber cloth (the raw material for the flexible micropillars of the present invention). The specimens consisted of two 1.8mm thick sheets of soda-lime glass with a 1.8mm thick interlayer. The test materials were placed in the interlayer for measurement using the Hangzhou Aihua AWA6290T Sound Insulation / Absorption Coefficient Test System. The test results are summarized in Table 2 below.

[0083] Table 2

[0084]

[0085] From the results in Table 2, we can see that:

[0086] Regardless of the material the micro-pillars are made of, the sound insulation of vacuum glass is greater than that of insulating glass of the same specifications;

[0087] The sound insulation efficiency of flexible micro-pillars mainly composed of ultra-fine glass fiber cloth is higher than that of tiny pillars such as stainless steel micro-beads, hollow or porous glass micro-beads.

[0088] This demonstrates that flexible micropillars based on fiberglass cloth also significantly outperform in sound insulation. Comparing stainless steel micropillars used in currently commercially available vacuum glazing with the fiberglass micropillars produced in this invention, the latter's weighted sound insulation (Rw) improves by 22% to 44dB. The latter's low-frequency average sound insulation improves by 35% to 46.6dB.

Claims

1. A flexible micro-pillar for vacuum glass, wherein: The flexible micro-pillar has at least one glass fiber layer; the flexible micro-pillar has a composite structure consisting of two or more glass fiber layers; The flexible micro-pillar has a composite structure consisting of at least two glass fiber layers and at least one metal layer and / or alloy layer, wherein the metal layer and / or alloy layer is located between the two glass fiber layers; The weaving direction of the glass fiber layer is parallel to the glass plate and perpendicular to the arrangement direction of the flexible micro-pillars; The metal layer or alloy layer is a metal foil or alloy foil; The diameter of the flexible micropillar is 0.2 mm-2.0 mm; The glass fiber layer is made of ultra-fine glass fibers; The material of the metal layer is one of aluminum, copper, iron, tin and zinc; The material of the alloy layer includes an alloy of two or more elements selected from aluminum, copper, iron, tin, and zinc.

2. The flexible micropillar according to claim 1, wherein The flexible micro-pillar has a composite structure consisting of at least three glass fiber layers and at least two metal layers and / or alloy layers, wherein the metal layers and / or alloy layers are spaced between the glass fiber layers.

3. The flexible micropillar according to claim 1 or 2, wherein: The thickness of the glass fiber layer is 0.1 mm to 3.0 mm.

4. The flexible micropillar according to claim 1 or 2, wherein: The thickness of the metal layer or alloy layer is less than 0.3 mm.

5. The flexible micropillar according to claim 4, wherein The thickness of the metal layer or alloy layer is 0.01 mm to 0.3 mm.

6. The flexible micropillar according to claim 1, wherein The diameter of the flexible micropillar is 0.2 mm-0.5 mm.

7. The flexible micropillar according to claim 1, wherein The thermal conductivity of the flexible micropillar at 25° C. is ≤1 W / m·K.

8. The flexible micropillar according to claim 7, wherein: The thermal conductivity of the flexible micropillar at 25° C. is ≤0.25 W / m·K.

9. The flexible micropillar according to claim 1, wherein: The material of the ultrafine glass fiber is one or a combination of two or more of aluminosilicate glass, boron aluminosilicate glass, soda-lime glass, borosilicate glass and quartz glass.

10. The flexible micropillar according to claim 1, wherein The thermal conductivity of the glass fiber layer at 25° C. is ≤0.03 W / m·K.

11. The flexible micropillar according to claim 1, wherein The specific surface area of ​​the glass fiber layer is 700-800m 2 / g.

12. The flexible micropillar according to claim 1, wherein The alloy includes stainless steel.

13. The flexible micropillar according to claim 1, wherein The cross section of the flexible micro-pillar is circular, elliptical, rectangular, triangular, polygonal with more than five sides, or ring-shaped.

14. The flexible micropillar according to claim 13, wherein: The ring includes a circular ring, a square ring, a triangular ring, a polygonal ring, and an irregular ring with a hollow portion and an outer periphery in different shapes.

15. The flexible micropillar according to claim 1, wherein The flexible micro-pillar is in a trapezoidal or columnar shape as a whole.

16. The flexible micropillar according to claim 15, wherein: The trapezoidal shape includes a frustum, an elliptical cone, a prism or an annular cone.

17. The flexible micropillar according to claim 16, wherein: The prism includes a triangular prism, a quadrangular prism, and a multi-prism with five or more edges; the annular platform includes a circular annular platform, a square annular platform or a polygonal prism.

18. The flexible micropillar according to claim 15, wherein The column shape includes a cylindrical shape, an elliptical cylindrical shape, a rectangular cylindrical shape, a prism shape or an annular cylindrical shape.

19. The flexible micropillar according to claim 18, wherein The prisms include triangular prisms, quadrangular prisms, and polygonal prisms with five or more edges; the annular columns include circular annular columns, square annular columns, or polygonal annular prisms.

20. The flexible micropillar according to claim 15, wherein The flexible micro-pillar is in a trapezoidal or columnar shape with irregular side surfaces.

21. The flexible micropillar according to claim 20, wherein The flexible micro-pillar is a drum-shaped pillar.

22. The flexible micropillar according to claim 1, wherein The height of the flexible micro-pillar under compression at a pressure of 1 atmosphere is not less than 0.10 mm.

23. The flexible micropillar according to claim 22, wherein: The height of the flexible micropillars under compression at a pressure of 1 atmosphere is 0.15-0.5 mm.

24. The flexible micropillar according to claim 23, wherein The height of the flexible micropillars under compression at a pressure of 1 atmosphere is 0.15-0.25 mm.

25. A vacuum glass, which uses the flexible micro-pillars according to any one of claims 1 to 24 as micro-pillars of a vacuum cavity.

26. The vacuum glass according to claim 25, wherein: The thermal conductivity of the flexible micropillar satisfies: In the above formula C pillars is the thermal conductivity of the flexible micropillar, in W / (m 2 K), k pillar is the thermal conductivity of the flexible micropillar, in W / (m·K), k g is the thermal conductivity of glass, in W / (m·K), a is the radius of the flexible micropillar in mm, b is the spacing distance between flexible micro-pillars, in mm, h is the height of the flexible micropillar in mm.

27. The vacuum glass according to claim 25 or 26, wherein: The spacing distance between the flexible micro pillars is not less than 30 mm.

28. The vacuum glass according to claim 27, wherein: The spacing between the flexible micro pillars is 40-60 mm.

29. The vacuum glass according to any one of claims 25-26 and 28, wherein: The height of the vacuum chamber is less than 0.3 mm.

30. The vacuum glass according to claim 29, wherein: The height of the vacuum chamber is 0.15-0.25 mm.

31. The vacuum glass according to claim 27, wherein: The height of the vacuum chamber is less than 0.3 mm.

32. The vacuum glass according to claim 31, wherein: The height of the vacuum chamber is 0.15-0.25 mm.

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