Electric heating glass laminate and electric heating glass

Abstract

The utility model discloses an electric heating glass laminated body and electric heating glass, and belongs to the technical field of glass. The electric heating glass laminated body comprises a first inorganic glass plate located on the outer side, a second inorganic glass plate arranged opposite to the first inorganic glass plate, and an electric heating film layer located between the first inorganic glass plate and the second inorganic glass plate. The electrothermal film layer is divided into a plurality of areas, and gaps exist between the areas; the peripheral edges of the first inorganic glass plate and the second inorganic glass plate and gaps between the areas of the electrothermal film layer are combined in a cold laser welding mode. According to the utility model, the novel electric heating glass laminated body is designed as the outer side electric heating glass layer, so that the electric heating film layer and the laminated layer in the electric heating glass are independent from each other and are not in contact with each other, the energy-saving effect and the heat transfer efficiency are improved, and the defect that the laminated layer is adjacent to the electric heating film is overcome.

Description

TECHNICAL FIELD

[0001] The utility model relates to electrothermal glass laminated body and electrothermal glass belongs to glass technical field. BACKGROUND

[0002] The window viewed from the cockpit of a commercial aircraft to the outside of the aircraft body is called an aircraft windshield, which is usually divided into left and right windshields. The window extending from the windshield glass to the rear two sides is a side window, which is also divided into left and right. The windshield glass window not only exists in commercial aircraft, but is also commonly used in various ground transportation tools, such as automobile windshield glass. However, the windshield glass on the aircraft and the windshield glass on the ground are different in structure, size, shape, and have considerable differences in their respective functions. For example, the primary protection of the aircraft windshield is bird strike, while the automobile windshield is mainly stone impact. For another example, the aircraft windshield needs high-strength heating function in the low-temperature environment at high altitude to prevent the outer surface of the glass from icing. Although the windshield glass of the ground transportation tool also has an electric heating function, it does not have the high requirements of the aircraft windshield in terms of heating power and speed. More than that, the aircraft windshield glass will experience a temperature difference change from ground temperature to about minus 50℃ at high altitude and a wind pressure change during each take-off and landing process. Therefore, the aircraft windshield glass undergoes a cycle of cold and hot and pressure every day, so the requirements for the aging resistance test of the aircraft windshield glass, especially the physical conditions such as temperature, humidity, and wind pressure, are much higher than those of the ground or sea transportation tools.

[0003] Since the aircraft windshield glass mainly considers safety factors including ① bird strike prevention, ② scratch prevention (icing particles), and ③ deterioration prevention of the electrothermal adhesive layer (water vapor penetration, cold and hot cycle), the windshield glass constituting a commercial aircraft usually adopts a three-layer composite glass structure. The outermost glass is relatively thin, which can use about 3mm of tempered sodium calcium glass or strengthened aluminum silicon glass. The inner side of the glass is coated with an electrothermal film layer and a conductive circuit, which serves as a heating source for the outer side of the windshield glass to prevent icing. The outer glass coated with the electrothermal film layer is continuously bonded to two pieces of high-strength glass in the inner side direction, with a thickness of 8-10mm. The three pieces of glass are bonded together by a hot-pressed adhesive sheet to form an integral body. The adhesive sheet can use PVB or TPU, etc. The two pieces of glass on the inner side mainly serve as structural support and provide safety strength. In addition to the basic requirements of safety and anti-icing, the entire window must meet the good visual requirements, and the glass shape needs to match the overall curved modeling of the aircraft, especially the gas power design of the aircraft head. Therefore, the aircraft windshield usually presents an irregular curved shape, and each part has certain requirements for strength, stress resistance, and shape change ability.

[0004] In the design of aircraft windshield, the three main safety factors are considered to improve the anti-collision ability, the use of high-strength glass plate is required, the glass strength can come from the material strength of the glass itself, or from the additional strength improved by physical or chemical strengthening; the scratch resistance requires to improve the surface hardness of the glass or the surface strength improved by glass strengthening; the third one is to avoid the unnecessary driving risk caused by the icing on the outer surface of the windshield, the focus is on the heating power of the electric heating device and the response time, and the electric heating device and the control system are highly reliable, which can effectively avoid the water vapor penetrating through the gap of the adhesive layer due to the adverse weather and wind pressure in flight, and finally leading to the deterioration of the heating layer or the oxidation of the conductive circuit.

[0005] In the sandwich structure of the aircraft windshield, the inner side of the glass plate contacting the atmospheric environment is coated with an electric heating material, usually a transparent conductive metal oxide, such as In2O3: Sn (ITO), SnO2: F (FTO), ZnO: Al (AZO), graphene film, etc. are all mature transparent conductive materials. Under the premise of ensuring the overall optical perspective clarity of the windshield, the composition, crystal form and thickness of the above transparent conductive film can adjust the surface resistance of the film layer at each location, which can provide sufficient heat to the windshield to prevent the glass surface from icing or fogging when powered externally, and ensure good visibility of the cockpit to the outside. In the traditional design, this layer of transparent conductive film is set between the outer glass plate that will contact the external environment and the intermediate layer glass plate, and is bonded with the adhesive layer. Whether the adhesive layer uses PVB or TPU, after years of aircraft take-off and landing and high-altitude flight, the adhesive layer is easily affected by environmental factors such as water vapor penetration and high-altitude radiation, and gradually deteriorates. In addition, the toughness of the organic adhesive layer will decrease with the decrease of temperature, that is, the organic adhesive layer will become brittle at very low environmental temperature, thereby affecting the material strength and toughness. When the aircraft flies from the ground to 10,000 meters altitude, the temperature range that the windshield needs to withstand is about 40℃ to -70℃, in addition to the decrease of toughness, the physical phenomenon of thermal expansion and contraction of the adhesive layer is also much larger than that of inorganic glass. After a long time, the electric heating film layer and the conductive circuit will have a high risk of being attacked by water vapor due to the aging of the adhesive material, thereby causing the failure of the electric heating function, and even worse, when the electric heating layer is in direct contact with the adhesive layer, the heating power of each area of the electric heating layer will vary with the icing condition, some areas have high power, and high heat zones are generated instantaneously, which also has the risk of thermal fatigue and thermal deterioration of the adhesive layer. This is one of the main failure reasons of the current aircraft windshield, that is, the failure points are mainly concentrated in the adhesive layer between the outer glass and the intermediate layer glass, and the bonding position of the adhesive layer and the electric heating film layer.

[0006] As mentioned above, the existing aircraft windshield glass electrothermal film is arranged on the inner surface of the outermost glass panel in front of the cockpit, coated on the glass surface in a film layer, and the material of the electrothermal film layer can be ITO, FTO, graphene, etc. A PVB or TPU adhesive layer is arranged adjacent to the electrothermal film layer, and the adhesive layer is used to bond the outermost glass panel (containing the electrothermal film layer) and the intermediate layer of aluminum-silicon glass panel to form a laminated panel. This structural arrangement inevitably causes the adhesive layer to be in direct contact with the electrothermal film layer and interact with each other. For example, when the electrothermal film layer is heated, it will have a thermal effect on the adjacent adhesive layer. In addition to the thermal expansion and contraction cycle, the local high temperature points caused by uneven heating also damage the service life of the adhesive layer. For PVB and TPU, which are commonly used adhesive layers, the process temperature during lamination with glass is 115-125°C. Both of them exhibit excellent bonding performance after lamination with glass panels, but some specially designed TPU can withstand cold temperatures as low as -70°C, which is better than the cold resistance temperature of PVB, which is about -40°C. Therefore, when laminating the windshield glass of commercial aircraft, TPU is preferred. Although the temperature range of TPU can cover -70 to 80°C, it can be used in the temperature range of aircraft from the ground to 10,000 meters in the air, but most organic polymer materials will become brittle at low temperatures, especially below the glass transition temperature (T g ) of the material. When the temperature is lower than T g , the mechanical behavior of the material will change from viscoelasticity to rigidity. Taking TPU as an example, its T g will change due to chemical composition and polymer structure, and it is usually distributed in the range of -40 to -60°C. When the TPU adhesive layer becomes rigid as the temperature decreases, it gradually loses elasticity and becomes brittle. If the windshield glass is curved, the interface between the TPU adhesive layer and the glass may accumulate stress due to temperature changes, which may cause the adhesive layer and the glass to peel off, which may weaken the overall structure of the windshield glass. Therefore, timely heating of the electrothermal film layer can not only prevent icing on the outer surface of the windshield glass, but also provide a certain temperature for the adhesive layer to avoid brittleness. Although the electrothermal film layer can provide warmth for the TPU adhesive layer, the direct contact between the TPU adhesive layer and the electrothermal film layer, i.e., the stacked structure of the two, still has the following disadvantages:

[0007] (1) Uneven heating causes local burns to the adhesive layer

[0008] Commercial aircraft has very high requirements for safety performance, any factor that can affect flight safety needs to be avoided and controlled in advance, and the safety of aircraft devices also needs to be monitored and managed at all times, especially for windshield glass. As mentioned earlier, when the electrothermal film layer and the TPU adhesive layer of the windshield glass are attached together, the heating power of the electrothermal film layer needs to match the curved shape of the windshield glass and the uneven icing condition of the outer surface. Although the electrothermal film layer itself is provided with a multi-point temperature monitoring device, the risk of local overheating still exists, and the overheated area may cause the adhesive layer to locally peel off, displace and slide, and be uneven in thickness. These defects can in turn cause the electrothermal film layer to peel off and damage the conductive circuit, ultimately affecting the overall safety of the windshield glass.

[0009] (2) Cold and hot cycle for the siphon phenomenon of the adhesive layer

[0010] The adhesive layer itself has a certain affinity to the water vapor in the air, especially PVB itself has relatively high water absorption. Generally speaking, the water content of PVB film when it leaves the factory is about 0.25-0.55%. If it is not stored in a dry environment, when the water content is higher than 1%, it will affect the bonding ability and usually will be discarded and not used again. The adhesive layer of the glass bonding that has been completed also needs to be waterproofed around the bonding layer to prevent water vapor in the air from gradually penetrating into the adhesive layer itself and the interface between the adhesive layer / glass and the adhesive layer / electrothermal film layer through the edge of the bonding layer. If the waterproofing around the bonding layer is aged or broken by impact or peeling, water vapor will gradually penetrate into the adhesive layer. After the adhesive layer absorbs water vapor and undergoes a cold and hot cycle, a siphon pump-like effect will occur. When the adhesive layer is heated, the volume expands and the high molecular net structure can accommodate more water vapor due to expansion. When it cools down, some of the water vapor condenses in the adhesive. Due to the capillary force, it is difficult to remove these condensed water. This cycle causes water vapor to gradually penetrate deeper into the adhesive layer, eventually causing the adhesive layer to lose adhesion and causing water vapor to begin to corrode the conductive circuit and the electrothermal film layer. Practical new content

[0011] To solve the above technical problems, the purpose of the present application is to provide an electrothermal glass layer stack and an electrothermal glass. The present application designs a new type of electrothermal glass layer stack as an outer electrothermal glass layer, so that the electrothermal film layer and the adhesive layer in the electrothermal glass are independent of each other and do not contact each other, which can improve the electrothermal effect and overcome the shortcomings of the adhesive layer being adjacent to the electrothermal film.

[0012] To achieve the above-mentioned purpose, the present application provides an electrothermal glass layer stack in the first aspect, which comprises: a first inorganic glass plate located on the outer side, a second inorganic glass plate placed opposite to the first inorganic glass plate, and an electrothermal film layer located between the first inorganic glass plate and the second inorganic glass plate.

[0013] The electric heating film layer is divided into several areas, and gaps exist between the areas.

[0014] The surrounding edges of the first inorganic glass plate and the second inorganic glass plate and the gaps existing between the areas of the electric heating film layer are combined in a cold laser welding manner.

[0015] In the electric heating glass laminate, the first inorganic glass plate and the second inorganic glass plate are welded at room temperature by using cold laser, without using any solder, and the outer electric heating glass layer obtained by welding the two glass plates without adhesive film bonding can achieve the effects of waterproof and airtight, and has a strength not lower than that of the original glass plate (i.e., a glass plate with a thickness equal to the total thickness of the first inorganic glass plate and the second inorganic glass plate).

[0016] In the electric heating glass laminate, preferably, the total thickness of the first inorganic glass plate and the second inorganic glass plate is x0, the thickness of the first inorganic glass plate is x1, The value of R is 0.3>R>0.05. By controlling R, that is, controlling the thickness ratio of the first inorganic glass plate and the second inorganic glass plate, better thermal efficiency can be provided, and better electric heating effect can be achieved. The original glass plate (i.e., a glass plate with a thickness equal to the total thickness of the first inorganic glass plate and the second inorganic glass plate) has better anti-icing function, and the inner glass of the electric heating film layer has better anti-fogging effect.

[0017] In the electric heating glass laminate, preferably, the thickness of the first inorganic glass plate is 1-3 mm.

[0018] In the electric heating glass laminate, preferably, the electric heating power density of each area of the several areas of the electric heating film layer, the area of each area of the several areas of the electric heating film layer, the resistivity of the material of the electric heating film layer, the thickness of the electric heating film layer, and the ratio of the length to the width of each area of the several areas of the electric heating film layer satisfy the following formula and the following conditions:

[0019]

[0020] P / S = P / S, wherein P is the electric heating power of each of the plurality of regions of the electric heating film layer, in watt; S is the area of each of the plurality of regions of the electric heating film layer, in square meter; P / S represents the electric heating power density of each of the plurality of regions of the electric heating film layer; U is the voltage applied to the electric heating film layer, in volt; θ is the ratio of the length to the width of each of the plurality of regions of the electric heating film layer; R S R = ρ / d, wherein R is the square resistance of the material of the electric heating film layer, in ohm; ρ is the resistivity of the material of the electric heating film layer, in ohm meter; and d is the thickness of the electric heating film layer, in meter; S R = ρ / d, wherein R is the square resistance of the material of the electric heating film layer, in ohm; ρ is the resistivity of the material of the electric heating film layer, in ohm meter; and d is the thickness of the electric heating film layer, in meter;

[0021] P / S is not less than 3000 W / m 2 .

[0022] More preferably, when the total area of the plurality of regions of the electric heating film layer is 0.7-1.1 m 2 , S is 0.2-0.4 m 2 .

[0023] More preferably, the ratio of the length to the width of each of the plurality of regions of the electric heating film layer is 1-2.5.

[0024] It should be noted that, as described below, since the actual shape of the electric heating glass of the present application can adopt a curved surface and / or various irregular shapes, the area of each of the plurality of regions of the electric heating film layer and the length and width of each of the plurality of regions of the electric heating film layer are calculated based on the equivalent area of the electric heating film layer, the shape of which is a rectangle, and thus the length and width of each of the plurality of regions of the electric heating film layer refer to the length and width of the rectangle, respectively. By partitioning the electric heating film layer and controlling d, θ, S and the number of the partitioned regions to satisfy the above relationships and conditions, the electric heating glass of the present application can achieve the electric heating power density range required to be controlled under the given voltage applied to the electric heating film layer and the resistivity of the material of the electric heating film layer, and thus can have excellent electric heating performance, i.e. energy saving effect and heat transfer efficiency, so that the effects of preventing the outer surface of the wind deflector from icing and the inner surface of the wind deflector from fogging are both optimal.

[0025] In the above electric heating glass laminate, preferably, the width of the gap between the regions of the electric heating film layer is 0.5-3.5 mm, more preferably 0.8-3.0 mm.

[0026] In the above electric heating glass laminate, preferably, the thickness of the electric heating film layer is 100 nm or less, more preferably 70 nm or less.

[0027] In the electrocaloric glass laminate described above, preferably, the material of the electrocaloric film layer comprises metal, inorganic metal oxide, or graphene, etc. More preferably, the material of the electrocaloric film layer comprises Ag, ITO (In2O3: Sn), FTO (SnO2: F), AZO (ZnO: Al), or graphene, etc.

[0028] The electrocaloric glass laminate of the utility model can be used as the outer electrocaloric glass layer of a windshield (especially an airplane windshield) and is mainly used for providing electrocaloric function. The utility model controls R in the range, controls the electric heating power density and d, theta, rho, S simultaneously and satisfies the above-mentioned relationship and condition, at least reaches the following effect: (1) after the electrocaloric film layer is electrified to generate heat, the heat transfer of the electrocaloric film layer inside and outside is better, the effect of preventing the outer surface of the windshield from icing and the inner surface from fogging is best; (2) compared with the prior art, the time of heat transfer to the outer surface is shortened and the energy consumption is reduced; (3) the interlayer can be kept at normal use temperature, the interlayer material will not be embrittled due to overcooling and lose strength and adhesion; (4) the temperature of the outer surface of the first inorganic glass plate (i.e. the outer surface of the windshield) is slightly higher than the freezing point (about 1.7 DEG C, i.e. about 35 DEG F), thereby avoiding the problem of accelerated aging of the interlayer, the conductive circuit and the like caused by excessively high temperature; (5) the heat loss of the outer surface of the windshield, such as free convection heat dissipation, thermal radiation heat dissipation, energy dissipation of heated water drop collision and water drop evaporation latent heat, is fully considered, and the outer surface of the windshield reaches excellent anti-icing effect.

[0029] According to the specific embodiment of the utility model, preferably, the electrocaloric glass laminate further comprises a conductive circuit, which is connected to the electrocaloric film layer. It should be noted that when the cold laser is used to weld the peripheral edges of the first inorganic glass plate and the second inorganic glass plate, the access port of the wire circuit should be left. In addition, the shape, area and the like of the several regions of the electrocaloric film layer involved in the above do not include the region of the access of the conductive circuit.

[0030] In the electrocaloric glass laminate described above, preferably, the first inorganic glass plate and the second inorganic glass plate respectively comprise chemically tempered glass plate, physically tempered glass plate or semi-tempered glass plate, etc. The types of the first inorganic glass plate and the second inorganic glass plate can be the same or different, as long as they are in the range.

[0031] In the electrocaloric glass laminate described above, preferably, the materials of the first inorganic glass plate and the second inorganic glass plate respectively comprise aluminum-silicon glass, lithium-aluminum-silicon glass, boron-silicon glass, boron-aluminum-silicon glass or sodium-calcium glass, etc. The materials of the first inorganic glass plate and the second inorganic glass plate can be the same or different, as long as they are in the range.

[0032] The second aspect of this utility model provides an electrothermal glass, which comprises, from the outside to the inside: an outer electrothermal glass layer, a first laminated layer, a middle glass layer, a second laminated layer and an inner glass layer;

[0033] Wherein, the outer electrothermal glass layer is the aforementioned electrothermal glass laminate;

[0034] The intermediate glass layer includes a third inorganic glass plate;

[0035] The inner glass layer includes a fourth inorganic glass plate;

[0036] The outer electrothermal glass layer, the first laminated layer, the middle glass layer, the second laminated layer, and the inner glass layer are combined into a whole.

[0037] In the above-mentioned electrothermal glass, preferably, the thickness of the third inorganic glass plate is 7-15 mm, more preferably 8-11 mm.

[0038] In the above-mentioned electrothermal glass, preferably, the thickness of the fourth inorganic glass plate is 4 to 12 mm, more preferably 5 to 10 mm.

[0039] In the aforementioned electrothermal glass, preferably, the third inorganic glass plate and the fourth inorganic glass plate respectively include chemically tempered glass, physically tempered glass, or semi-tempered glass. The types of the third inorganic glass plate and the fourth inorganic glass plate can be the same or different, as long as they fall within this range.

[0040] In the aforementioned electrothermal glass, preferably, the materials of the third and fourth inorganic glass plates include aluminosilicate glass, lithium aluminosilicate glass, borosilicate glass, borosilicate glass, or soda-lime glass, respectively. The materials of the third and fourth inorganic glass plates can be the same or different, as long as they fall within this range.

[0041] In the above-mentioned electrothermal glass, preferably, the thickness of the first interlayer is 2.2 to 6.0 mm, more preferably 3.0 to 5.3 mm.

[0042] In the above-mentioned electrothermal glass, preferably, the thickness of the second interlayer is 1.5 to 5.3 mm, more preferably 2.2 to 4.5 mm.

[0043] In the aforementioned electrothermal glass, preferably, the materials of the first interlayer and the second interlayer include TPU, PVB, EVA, or SGP, respectively.

[0044] According to a specific embodiment of the present invention, preferably, the shape of the electrothermal glass includes a plane, a single curved surface, a hyperbolic surface, or a spherical surface.

[0045] According to the specific embodiment of the utility model, preferably, the electrothermal glass further comprises a peripheral sealant arranged at the peripheral edge of the whole of the outer electrothermal glass layer, the first interlayer, the intermediate glass layer, the second interlayer and the inner glass layer, for providing airtight packaging and edge protection.

[0046] The preparation method of the electrothermal glass can comprise the following steps:

[0047] S1: plating an electrothermal film layer on the surface of the first inorganic glass plate, and separating the electrothermal film layer into several regions with gaps between the regions;

[0048] S2: combining the first inorganic glass plate plated with the electrothermal film layer and the peripheral edge of the second inorganic glass plate and the gaps between the regions of the electrothermal film layer in a cold laser welding manner, to form an outer electrothermal glass layer (i.e. the electrothermal glass stack of the utility model);

[0049] S3: using the material of the first interlayer and the material of the second interlayer to bond the outer electrothermal glass layer, the third inorganic glass plate and the fourth inorganic glass plate together to form the first interlayer, the second interlayer, the intermediate glass layer and the inner glass layer, and to make the first interlayer located between the outer electrothermal glass layer and the intermediate glass layer, and the second interlayer located between the intermediate glass layer and the inner glass layer, to obtain the electrothermal glass.

[0050] The electrothermal glass stack and the electrothermal glass of the utility model can be applied in the fields of windshield glass, side window, chord window and escape window.

[0051] The electrothermal glass stack of the utility model can be applied in the fields of windshield glass, side window, chord window and escape window of a vehicle alone, or can be applied in the fields of windshield glass, side window, chord window and escape window of a vehicle through structural design of combination with other glass (such as the electrothermal glass of the utility model). Preferably, the windshield glass comprises airplane windshield glass, automobile windshield glass, windshield glass of rail vehicle and windshield glass for ships and submersibles.

[0052] In the electric heating glass, the electric heating film layer and the laminated layer are independent and do not contact each other, and the following defects of the current aircraft windshield glass are overcome: ① uneven heating causes local scalding of the laminated layer and ② cold and hot cycles cause siphoning of the laminated layer. At the same time, the glass material currently used is strictly certified, so under the premise of not changing the glass material, the thickness, strength and weight of the glass plate and the thickness of the laminated layer matched are also strictly regulated. The electric heating film layer and the laminated layer are separated in the utility model, without affecting the safety structure of the original electric heating glass. Based on the weight and strength of the windshield electric heating glass, the total thickness of the first inorganic glass plate and the second inorganic glass plate is equivalent to the thickness of the original outer glass plate, so the thickness of the glass plate is not increased, and the weight of the glass plate is not increased. The electric heating film layer is arranged in the middle of the two glass plates (i.e. the first inorganic glass plate and the second inorganic glass plate), and the advanced cold laser welding process is used to re-weld the two glass plates into one glass plate. The shape, thickness and weight of the welded glass plate are the same as or very close to those of the original outer glass plate. The utility model adopts the composite glass plate with the same thickness as the original outer glass plate but with the electric heating film layer instead of the original outer glass plate. The electric heating film layer is arranged in the two glass plates to form a glass plate, but not laminated. As described above, the material of the electric heating film layer can include a metal film such as silver, or a metal oxide film such as ITO, FTO, AZO, or a graphene film; the above-mentioned film materials do not have adhesion at room temperature. The prior art process cannot fix the electric heating film with no adhesion in the middle of the two glass plates at room temperature. The structure design and the use of the cold laser welding process of the utility model not only form an outer electric heating glass layer with electric heating function, but also ensure that the combined outer electric heating glass layer has a strength and optical property not lower than that of the original windshield glass outer glass plate, and can efficiently prevent water vapor from penetrating into the electric heating film layer from the edge, without contacting the laminated layer to avoid deterioration of the laminated layer, and also improves the energy saving effect and heat transfer efficiency of the outer electric heating glass layer.

[0053] At the same time, the utility model does not change the existing first laminated layer, second laminated layer, middle glass layer and inner glass layer, but integrates the composite glass plate with the electric heating film layer and the original first laminated layer, second laminated layer, middle glass layer and inner glass layer into a complete windshield glass.

[0054] The utility model at least has the following beneficial effects:

[0055] (1) does not change the main structure of the existing standard-compliant windshield glass, and the existing design of the middle glass layer and the inner glass layer for providing structural support strength, and the first and second interlayer layers is maintained, that is, the safety structure and strength of the windshield glass are not affected.

[0056] (2) the electric heating glass stack (i.e., the outer electric heating glass layer) of the utility model is a structure in which an electric heating film layer is disposed between two thin glass sheets and is formed by cold laser welding, and the function of the electric heating glass stack is to provide electric heating and prevent icing. The electric heating glass stack is not a structural member, so it does not affect the safety performance of the windshield glass. At the same time, the electric heating glass stack overcomes the above-mentioned shortcomings of the interlayer layer adjacent to the electric heating film due to its structural design and cold laser welding process, and has good electric heating effect, thereby having excellent anti-icing effect. Moreover, the electric heating film layer in the electric heating glass stack is closer to the outer surface of the windshield glass, and compared with the original windshield glass heating system, the electric heating glass stack of the utility model has better energy-saving effect and better heat transfer efficiency. In addition, the electric heating film layer is divided into several areas, which can provide different electric power and convert into different heat for heating the electric heating glass stack at different positions. Moreover, the electric heating glass stack of the utility model is welded by cold laser at room temperature, without using any solder, and the electric heating glass stack obtained by welding two glass sheets without adhesive film bonding can achieve waterproof and airtight effect. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 The structure diagram of the electric heating glass stack is provided for the specific embodiment of the utility model.

[0058] Figure 2 The structure diagram of the electric heating glass is provided for the specific embodiment of the utility model.

[0059] Figure 3 The structure diagram of the aircraft windshield glass is provided for the specific embodiment of the utility model.

[0060] Figure 4 The structure diagram of the stainless steel plate group with a hollow area is provided for the specific embodiment of the utility model.

[0061] Figure 5 The structure diagram of the cold laser welding structure is provided for the specific embodiment of the utility model.

[0062] Figure 6 The P / S value and the highest equilibrium temperature curve in the test example.

[0063] BRIEF DESCRIPTION OF DRAWINGS

[0064] 1-outer electric heating glass layer; 2-first interlayer; 3-intermediate glass layer; 4-second interlayer; 5-inner glass layer;

[0065] 101-first inorganic glass plate; 102-second inorganic glass plate; 103-electric heating film layer. DETAILED DESCRIPTION

[0066] In order to have a clearer understanding of the technical features, objects and beneficial effects of the present application, the technical scheme of the present application will be described in detail as follows, but it should not be understood as a limitation on the scope of the present application.

[0067] Electrothermal glass laminate

[0068] The specific embodiment of the present application provides an electric heating glass laminated body, as shown in the formula: Figure 1 The specific embodiment of the present application provides an electric heating glass laminated body, as shown in the formula:

[0069] The electric heating film layer 103 is divided into several regions, and there is a gap between each region.

[0070] The surrounding edges of the first inorganic glass plate 101 and the second inorganic glass plate 102 and the gap between each region of the electric heating film layer 103 are combined by cold laser welding.

[0071] Wherein, the total thickness of the first inorganic glass plate 101 and the second inorganic glass plate 102 is x0, the thickness of the first inorganic glass plate 101 is x1, The value of R is 0.3>R>0.05.

[0072] The electric heating power density of each region in the several regions of the electric heating film layer 103, the area of each region in the several regions of the electric heating film layer 103, the resistivity of the material of the electric heating film layer 103, the thickness of the electric heating film layer 103, the ratio of the length and width of each region in the several regions of the electric heating film layer 103 satisfy the following formula and the following conditions:

[0073]

[0074] Wherein, P is the electric heating power of each area of the plurality of areas separated by the electric heating film layer 103, in watt; S is the area of each area of the plurality of areas separated by the electric heating film layer 103, in square meter; P / S represents the electric heating power density of each area of the plurality of areas separated by the electric heating film layer 103; U is the voltage of the electric heating film layer 103, in volt; θ is the ratio of the length and the width of each area of the plurality of areas separated by the electric heating film layer 103; R S is the square resistance of the material of the electric heating film layer 103, in ohm, and R S = ρ / d, ρ is the resistivity of the material of the electric heating film layer 103, in ohm meter; d is the thickness of the electric heating film layer 103, in meter;

[0075] P / S is not less than 3000W / m 2 at -40℃;

[0076] When the total area of the plurality of areas separated by the electric heating film layer 103 is 0.7-1.1m 2 ,S is 0.2-0.4m 2 ;

[0077] The ratio of the length and the width of each area of the plurality of areas separated by the electric heating film layer 103 is 1-2.5.

[0078] Electrothermal glass

[0079] The specific embodiment of the utility model provides a kind of electric heating glass, as shown in figure, which comprises: outer electric heating glass layer 1, first interlayer 2, intermediate glass layer 3, second interlayer 4 and inner glass layer 5 from outside to inside in sequence. Figure 2

[0080] Wherein, outer electric heating glass layer 1 includes: the first inorganic glass plate 101 located on the outside, the second inorganic glass plate 102 placed opposite to the first inorganic glass plate 101, and the electric heating film layer 103 between the first inorganic glass plate 101 and the second inorganic glass plate 102.

[0081] The electric heating film layer 103 is separated into a plurality of areas, and there is a gap between each area.

[0082] The surrounding edge of the first inorganic glass plate 101 and the second inorganic glass plate 102 and the gap between each area of the electric heating film layer 103 are combined in a cold laser welding manner.

[0083] Intermediate glass layer 3 includes a third inorganic glass plate.

[0084] Inner glass layer 5 includes a fourth inorganic glass plate.

[0085] The outer side electric heating glass layer 1, the first laminated layer 2, the middle glass layer 3, the second laminated layer 4 and the inner side glass layer 5 are combined as a whole.

[0086] The electric heating glass can be used as a windshield glass, for example, an airplane windshield glass, an automobile windshield glass, a windshield glass of a rail transit tool and a windshield glass for a ship and a submersible, and is preferably used as an airplane windshield glass.

[0087] The structure of the airplane windshield glass is as shown in the figure. Figure 3 The airplane windshield glass can be divided into a left windshield and a right windshield, and the structures of the left windshield and the right windshield are symmetrical. Figure 3 The electric heating film layer 103 is divided into several areas and the areas for cold laser welding, and the areas of the electric heating film layer 103 are located on the same plane but have different plane positions. The electric heating film layer 103 is divided into several areas, different electric powers can be provided and different heat can be converted, the outer side electric heating glass layer 1 at different positions is heated, and the use requirements of the windshield glass, especially the airplane windshield glass, are met. In addition, the cold laser welding process is used, which makes the division of the areas of the electric heating film layer 103 and the manufacturing process of the electric heating glass more precise and effective. At the same time, the electric heating film and the laminated layer are separated by the structure design and the cold laser welding process, and the technical progress of the electric heating glass as a windshield glass is realized.

[0088] Cryo laser welding

[0089] The gaps between the surrounding edges of the first inorganic glass plate 101 and the second inorganic glass plate 102 and the areas of the electric heating film layer 103 are combined by cold laser welding. The electric heating film layer 103 is arranged between the first inorganic glass plate 101 and the second inorganic glass plate 102, but is not attached by using a film, and as described above, the material of the electric heating film layer is metal, or inorganic metal oxide, or graphene, etc., which does not have adhesion, and other processing technologies cannot complete the fastening and splicing of the two glass plates with the middle layer of the electric heating film layer without adhesion. The outer side electric heating glass layer 1 is formed by cold laser welding, which ensures that the outer side electric heating glass layer 1 has a strength and optical properties not lower than those of the existing outer side glass plate, and can efficiently prevent water vapor from penetrating into the electric heating film layer 103 from the edges to cause defects such as deterioration and oxidation of the electric heating film and the conductive circuit, and does not contact the laminated layer to avoid deterioration of the laminated layer.

[0090] The utility model discloses a cold laser welding mode is used to combine first inorganic glass plate 101 and second inorganic glass plate 102 with electric heating film layer 103 to be combined into a piece of glass with point, line, surface welding mode, namely outside electric heating glass layer 1, guarantee the heating function of electric heating film layer 103, also promote the toughness and waterproof insulation ability of outside electric heating glass layer 1. The cold laser welding does not need to use any solder, interface active agent and the like chemical medium, is a kind of high-efficiency clean energy environmental protection glass welding process that can be carried out at normal temperature, since it is welded at normal temperature, the plasma high-energy reaction of femtosecond or picosecond laser at setting position instantaneously combines two glass plates into a piece of glass, the welding place of outside electric heating glass layer 1 after cold laser welding can be understood as fusion into one, therefore its density and bonding strength are equivalent to glass fusion, far more than traditional glass patching after adhesive.

[0091] The utility model discloses outside electric heating glass layer 1 is formed using cold laser welding, it has not less than the strength of current outside glass plate (i.e. the glass plate of the total thickness of first inorganic glass plate and second inorganic glass plate), even the strength of promotion. For example, using 2 pieces of sodium calcium glass or aluminum silicon glass with thickness of 0.9mm and 2.1mm as first inorganic glass plate 101 and second inorganic glass plate 102 respectively, after cold laser welding, equivalent to form a piece of 3mm thick glass, if glass plate is chemically strengthened in advance, then for two glass plates, a total of four glass plate surfaces are chemically strengthened, after cold laser welding patching, its strength is greater than a piece of only two faces are strengthened 3mm glass.

[0092] When carrying out cold laser welding, in addition to the position of the reserved conductive circuit (can also include temperature sensor and signal circuit) access, the gap between the surrounding edge of first inorganic glass plate 101 and second inorganic glass plate 102 and each area of electric heating film layer 103 is the position of cold laser welding, can be with the welding mode of point, line, face to the electric heating film of each area is separated and sealed.

[0093] In some specific embodiments, when cold laser welding is used, the number of welding lines is determined according to the following formula:

[0094]

[0095] Wherein, N is the number of welding lines, unit: strip;

[0096] w is the average width of the solder wire, in mm;

[0097] S sealing w is the average width of the solder wire, in mm 2 ;

[0098] a is the thermal expansion coefficient of the first inorganic glass sheet 101, in ℃ -1 ;

[0099] ΔT is the temperature difference between the two surfaces (two surfaces in the thickness direction) of the outer electrically heated glass layer 1 formed after welding, in ℃;

[0100] E is the elastic modulus (i.e., Young's modulus) of the first inorganic glass sheet 101, in MPa;

[0101] H is the thickness of the first inorganic glass sheet 101 after thermal expansion, in mm.

[0102] In some embodiments, the number of solder wires is ≥ 2.

[0103] In some embodiments, the cold laser uses a laser pulse half-width (Pulse Width, FWHM, or pulse duration) of 20 picoseconds or less.

[0104] In some embodiments, the cold laser welding uses a laser wavelength of 800 nm-1600 nm, such as 800 nm, 1045 nm, 1558 nm, 1064 nm, with 1064 nm being preferred.

[0105] In some embodiments, the cold laser uses a laser repetition rate of 1 Hz-10 MHz. For example, but not limited to, Wuhan Rikke Fiber Laser Technology Co., Ltd. picosecond laser, laser pulse half-width is 800 fs (i.e., 0.8 ps), MKS Spectra-Physics IceFyre 1064-50 laser, laser pulse half-width is 10 ps. Different laser wavelengths with different operating parameters can produce different welding effects, but they can all firmly weld the first inorganic glass sheet 101 and the second inorganic glass sheet 102 together. Currently, the wavelengths, pulse repetition rates, and pulse durations of lasers that have been proven to be used for glass laser welding are summarized in Table 1 below.

[0106] Table 1

[0107] Laser wavelength Repetition rate Pulse length 800 nm 1 kHz 85 fs 1045 nm 500 kHz - 1 MHz 350 - 400 fs 1558 nm 500 kHz 950 fs 1064 nm 500 kHz - 1 MHz 10 ps - 325 fs

[0108] In some embodiments, the first inorganic glass sheet 101 and the second inorganic glass sheet 102 at the soldering position must be tightly bonded, and the gap between the first inorganic glass sheet 101 and the second inorganic glass sheet 102 at the soldering position is less than 40 μm, preferably less than 25 μm.

[0109] In some embodiments, the width of the soldering line is less than 20 μm, preferably less than 5 μm.

[0110] In some embodiments, the soldering strength of the soldering line is greater than the thermal expansion shear stress between the first inorganic glass sheet 101 and the second inorganic glass sheet 102 to be soldered; preferably, the soldering strength of the soldering line is at least greater than 1 MPa or satisfies the following condition:

[0111]

[0112] wherein S sealing is the soldering strength, in MPa;

[0113] α is the thermal expansion coefficient of the first inorganic glass sheet 101, in ℃ -1 ;

[0114] ΔT is the temperature difference between the two surfaces (two surfaces in the thickness direction) of the outer electrocaloric glass layer 1 formed after soldering, in ℃;

[0115] E is the elastic modulus (i.e. Young's modulus) of the first inorganic glass sheet 101, in MPa;

[0116] H is the thickness of the first inorganic glass sheet 101 expanded by heat, in mm;

[0117] d is the width of the soldering sealing area, in mm.

[0118] In some embodiments, the interval distance of the soldering line is greater than 150 μm, and the depth of the soldering line is greater than 20 μm.

[0119] Method for manufacturing electrothermal glass

[0120] As Figure 2 shown in the structure of the electrocaloric glass preparation process: hot bending forming→ chemical tempering→ electrocaloric film layer plating→ cold laser soldering→ glass lamination. The specific description is as follows:

[0121] Step 1: Hot bending forming

[0122] A 0.9mm thick lithium aluminum silicon glass is used as the first inorganic glass plate 101, a 2.1mm thick lithium aluminum silicon glass is used as the second inorganic glass plate 102, and two 9mm thick lithium aluminum silicon glass plates are used as the third and fourth inorganic glass plates. The second inorganic glass plate 102 is slightly smaller than the first inorganic glass plate 101, for example, the width of the second inorganic glass plate 102 is 10mm smaller than the first inorganic glass plate 101, but the lengths are the same; the first, third, and fourth inorganic glass plates are the same size. The four glass plates are hot-bent using a conventional hot-bending process to ensure that the curvature of the four glass plates is consistent.

[0123] Step 2: Chemical tempering (i.e., chemical strengthening)

[0124] The four glass plates, after being hot-bent, are chemically tempered using the existing ion exchange method.

[0125] Step 3: Electrothermal film coating

[0126] A 2mm thick stainless steel plate assembly with a perforated area is placed on the surface of the first inorganic glass plate 101 after chemical tempering. The curvature of the stainless steel plate assembly is the same as that of the first inorganic glass plate 101, and the outer dimensions of the stainless steel plate assembly are the same as those of the first inorganic glass plate 101. The width of its non-perforated area is 3mm / 10mm. Figure 4 As shown, the stainless steel plate assembly is fixed to the surface of the first inorganic glass plate 101 with high-temperature tape, with the stainless steel plate assembly facing upwards and the first inorganic glass plate 101 facing downwards (relative to the coating direction). ITO coating is performed using a vertical coating equipment, and the hollowed-out areas are uniformly coated with an electrothermal film, such as an ITO film, resulting in an electrothermal film layer 103 with a thickness of 70 nm. Therefore, the electrothermal film layer 103 is divided into several regions, with gaps between each region. The width of the gaps between the regions of the electrothermal film layer 103 is 3 mm.

[0127] Step 4: Cold laser welding

[0128] The laser parameters used in this embodiment are shown in Table 2 below.

[0129] Table 2

[0130] Laser source type Femtosecond infrared solid-state laser Central wavelength 1064 nm Pulse width <800fs Repetition frequency ≤ 1 MHz Maximum single pulse energy 100 μJ Beam quality M 2 ]]> ≤1.2 Power stability <3％ Beam diameter 50 μm Laser power 9W

[0131] Remove the stainless steel plate group, the first inorganic glass plate 101 plated with the electrothermal film layer 103 and the second inorganic glass plate 102 after chemical toughening are aligned and stacked in the center, with the electrothermal film layer 103 sandwiched between the two glass plates, and the gaps between the periphery of the first inorganic glass plate 101 and the second inorganic glass plate 102 and each area of the electrothermal film layer 103 (i.e. the area not plated with the electrothermal film layer 103) are welded together using a femtosecond infrared solid-state laser, forming an outer electrothermal glass layer 1. Each welding area has 10 welding lines, with a welding line spacing of 0.2 mm, a welding line width of 15 μm, a welding line depth of 110 μm, and a welding strength of 19 MPa. The schematic diagram of the welding structure is shown in Figure 5 Figure 5 The welding lines are simplified to 5 lines in the figure for clarity. Figure 5 After cold laser welding, the electrothermal film layer 103 is protected between the first inorganic glass plate 101 and the second inorganic glass plate 102. As shown in

[0132] Step 5: Glass lamination

[0133] The third inorganic glass plate, the fourth inorganic glass plate and the outer electrothermal glass layer 1 after chemical toughening are laminated together at 150°C and 2 MPa using a TPU film to form a first lamination layer 2, a second lamination layer 4, an intermediate glass layer 3 and an inner glass layer 5, with the first lamination layer 2 between the outer electrothermal glass layer 1 and the intermediate glass layer 3, and the second lamination layer 4 between the intermediate glass layer 3 and the inner glass layer 5, to obtain an electrothermal glass. The thickness of the first lamination layer 2 is 4.5 mm, and the thickness of the second lamination layer 4 is 2.28 mm.

[0134] In the above description, let the total thickness of the first inorganic glass plate 101 and the second inorganic glass plate 102 be x0, and let the thickness of the first inorganic glass plate 101 be x1, Then the value of R is 0.3.

[0135] The electrothermal film layer 103 is divided into several areas in a direction parallel to the width of the electrothermal film layer 103. The shape of each area of the electrothermal film layer 103 is rectangular (ignoring the area connected to the conductive circuit).

[0136] The electrical heating power density of each area of the electrothermal film layer 103 divided into several areas, the area of each area of the electrothermal film layer 103 divided into several areas, the resistivity of the material of the electrothermal film layer 103, the thickness of the electrothermal film layer 103, and the ratio of the length and width of each area of the electrothermal film layer 103 divided into several areas satisfy the following formula and the following conditions:

[0137] ​

[0138] wherein P is the electric heating power of each of the separated areas of the electric heating film layer 103, in watt (W); S is the area of each of the separated areas of the electric heating film layer 103 (i.e. the area of each of the areas that can generate heat after being powered), in square meter (m 2 ); P / S represents the electric heating power density of each of the separated areas of the electric heating film layer 103 (i.e. the electric heating power per unit area); U is the power-on voltage of the electric heating film layer 103, in volt (V); θ is the ratio of the length to the width of each of the separated areas of the electric heating film layer 103; R S is the square resistance of the material of the electric heating film layer 103, in ohm (Ω), and R S = p / d, p is the resistivity of the material of the electric heating film layer 103, in ohm meter (Ωm); d is the thickness of the electric heating film layer 103, in meter (m);

[0139] P / S is not less than 3000 W / m 2 when the external ambient temperature is -40°C;

[0140] S is 0.2-0.4 m 2 when the total area of the separated areas of the electric heating film layer 103 is 0.7-1.1 m 2 ;

[0141] The ratio of the length to the width of each of the separated areas of the electric heating film layer 103 is 1-2.5.

[0142] Taking ITO film as an example, if the resistivity (p) of the ITO film is 5 x 10 -7 Ωm, the selected electric heating power density (P / S) is 7750 W / m 2 , and the power-on voltage (U) is 220 V. The total area of the separated areas of the electric heating film layer 103 used is 0.9 m 2 (the area of the access conductive circuit is ignored), the total area of 0.9 m 2 must be separated into several areas (although the electric heating glass of the present embodiment is a curved surface design, the equivalent area is calculated), and the thickness (d) of the electric heating film layer 103, the area (S) of each of the separated areas of the electric heating film layer 103, the ratio (θ) of the length to the width of each of the separated areas of the electric heating film layer 103, and the number of the separated areas must satisfy the relationship represented by the above formula and the above conditions, so as to satisfy the specified voltage, resistivity and electric heating power density.

[0143] For the 0.9 m 2The total area of the glass sample is 0.9 m2, and the area (S) of each region is 0.3 m2. 2 The values of different d and θ are shown in Table 3. Meanwhile, based on actual application, the length value of each region can be selected, and then the width value is determined according to θ.

[0144] Table 3

[0145] d (nm) Rs (Ω) θ Length (m) Width (m) [S(m 2 )]]> 20 25.00 0.83 0.500 0.600 0.30 22 22.73 0.92 0.524 0.572 0.30 24 20.83 1.00 0.548 0.548 0.30 26 19.23 1.08 0.570 0.526 0.30 28 17.86 1.17 0.591 0.507 0.30 30 16.67 1.25 0.612 0.490 0.30 32 15.63 1.33 0.632 0.475 0.30 34 14.71 1.42 0.652 0.460 0.30 36 13.89 1.50 0.671 0.447 0.30 38 13.16 1.58 0.689 0.435 0.30 40 12.50 1.67 0.707 0.424 0.30 42 11.90 1.75 0.724 0.414 0.30 44 11.36 1.83 0.741 0.405 0.30 46 10.87 1.92 0.758 0.396 0.30 48 10.42 2.00 0.774 0.387 0.30 50 10.00 2.08 0.790 0.380 0.30 52 9.62 2.16 0.806 0.372 0.30 54 9.26 2.25 0.821 0.365 0.30 56 8.93 2.33 0.836 0.359 0.30 58 8.62 2.41 0.851 0.352 0.30 60 8.33 2.50 0.866 0.347 0.30 62 8.06 2.58 0.880 0.341 0.30 64 7.81 2.66 0.894 0.336 0.30 66 7.58 2.75 0.908 0.330 0.30 68 7.35 2.83 0.922 0.326 0.30 70 7.14 2.91 0.935 0.321 0.30 72 6.94 3.00 0.948 0.316 0.30 74 6.76 3.08 0.961 0.312 0.30 76 6.58 3.16 0.974 0.308 0.30 78 6.41 3.25 0.987 0.304 0.30 80 6.25 3.33 1.000 0.300 0.30 82 6.10 3.41 1.012 0.296 0.30 84 5.95 3.50 1.024 0.293 0.30 86 5.81 3.58 1.036 0.289 0.30 88 5.68 3.66 1.048 0.286 0.30 90 5.56 3.75 1.060 0.283 0.30 92 5.43 3.83 1.072 0.280 0.30 94 5.32 3.91 1.084 0.277 0.30 96 5.21 4.00 1.095 0.274 0.30 98 5.10 4.08 1.106 0.271 0.30 100 5.00 4.16 1.118 0.268 0.30

[0146] In the following test examples, graphene is used as the material of the electrothermal film layer. Although the ITO film has been used as the material of the electrothermal film layer of the aircraft windshield glass for more than 50 years, due to the development of graphene materials in recent years, the graphene material is superior to the traditional ITO film material in terms of electrical conductivity, transparency, moisture resistance, temperature resistance, chemical stability, etc. Therefore, the electrothermal film layer in the following test examples is made of graphene material. No matter which electrothermal film material is used, it is suitable for the utility model.

[0147] Test Example 1: The electrothermal power required to maintain 1.5°C under different R values, different environmental temperatures, no insulation of the bottom plate glass, and the outer surface of the cover plate glass has been heated to 1.5°C

[0148] In this test, a hygrothermal exchange simulation environment aging low-temperature test chamber (Shenzhen Maruzen Company) is used as the test environment. The glass sample used for testing has a size of 260 mm x 260 mm. The bottom plate is 8 mm thick soda-lime glass, and the cover plate is 0.7 mm (R = 0.08) and 4 mm (R = 0.33) thick soda-lime glass. The electrothermal film layer is simulated between the bottom plate and the cover plate. Graphene is used as the material of the electrothermal film layer, and the thickness of the electrothermal film layer is about 18 nm. The electrothermal film layer is equipped with appropriate heating modules and temperature control modules, and an on-off type temperature controller is used for temperature control. A temperature sensor made of Pt-100 is placed at the center point of the cover plate to measure the temperature close to the outer surface of the cover plate glass. The outer sides of the cover plate and the bottom plate are directly exposed to the cold air in the low-temperature test chamber. The relative humidity in the test chamber is set to 50%. The measured electrothermal power refers to the electrothermal power required to raise the environmental temperature to 1.5°C on the outer side of the cover plate. This test is conducted without insulation of the bottom plate, so the heat of the electrothermal film layer is transferred to the cover plate above and the bottom plate below at the same time.

[0149] The test results are shown in Table 4.

[0150] Table 4

[0151] Cover thickness Corresponding R value Ambient temperature (°C) -30 -20 -10 0.7 mm 0.08 Temperature-maintaining electrothermal power (W) 34 24 13 4 mm 0.33 Temperature-maintaining electrothermal power (W) 86 39 23

[0152] From the data in Table 4, it can be seen that, under the same bottom plate condition, the electric heating power required to maintain the outer surface temperature at 1.5°C is smaller for the cover plate with a thickness of 0.7 mm (corresponding to R=0.08) than for the cover plate with a thickness of 4 mm (corresponding to R=0.33), and the required electric heating power gradually decreases as the ambient temperature increases from -30°C to -10°C; however, at any ambient temperature, the cover plate with a thickness of 4 mm requires more heat than the cover plate with a thickness of 0.7 mm to maintain the outer surface temperature at 1.5°C.

[0153] Test Example 2: Electric heating power required for the cover plate glass to be heated from the ambient temperature to 1.5°C under different R values and different ambient temperatures (differences from Test Example 1: ① bottom plate heat preservation, ② electric heating power required for the heating process from the ambient temperature to 1.5°C)

[0154] The samples and devices used in this test are basically the same as in Test Example 1, with the only difference being that a foamed plastic heat insulation plate with a heat transfer coefficient of 2.16 W / m 2 ·K is considered to be that the heat generated by the electric heating film layer is only transmitted outward in the direction of the cover plate, and the bottom plate direction is blocked by the heat insulation plate. The electric heating power required for heating is calculated by integrating the instantaneous electric heating power corresponding to each temperature point in the heating stage and then taking the average value with respect to the heating time.

[0155] The test results are shown in Table 5 below.

[0156] Table 5

[0157]

[0158] From the data in Table 5 above, it can be seen that the smaller the R value (for example, 0.08), the smaller the electric heating power required for heating at different ambient temperatures, and at the same time, the shorter the time required to heat from the ambient temperature to the target temperature of 1.5°C.

[0159] Test Example 3: Electric heating power and heating time required to heat to 1.5°C under the same ambient temperature of -5°C and bottom plate heat preservation condition

[0160] The device in this test is basically the same as in Test Example 2, but the thickness of the cover plate glass is changed to 2.00 mm, 2.84 mm, and 4.86 mm, and the electric heating power and heating time required to heat the cover plate glass from the ambient temperature of -5°C to 1.5°C are tested.

[0161] The test results are shown in Table 6 below.

[0162] Table 6

[0163] Cover thickness (mm) Corresponding R value Electrothermal power (W) Heating time (sec) 2 0.2 21.2 21.4 2.84 0.26 26.1 38.8 4.86 0.38 33.1 76

[0164] From the data in Table 6 above, it can be seen that at the same ambient temperature, as the R value increases, that is, the cover glass thickness increases, the electric heating power required to heat the outer surface of the cover glass to 1.5°C also increases, and the time required to heat to the target temperature also increases significantly, and when R exceeds the range of the present application (i.e., when R > 0.3), the time required to heat to the target temperature increases significantly.

[0165] Test Example 4: Electric heating characteristics discussion ①: Electric heating effect of different length-width ratios under the same voltage and the same area

[0166] The electric heating effect of graphene electric heating film layer applied to windshield electric heating glass can be verified by the following experiment. The glass plated with graphene electric heating film layer has a thickness of 3.91 mm, the thickness of the graphene electric heating film layer is about 18 nm, and the square resistance value is 12.42Ω. This glass is used as a bottom plate glass, silver paste is used as the positive and negative electrodes and is connected to the external fixed voltage, a heat insulation plate is placed below the bottom plate to control the heat flow to be transmitted only in the direction of the cover plate. The thickness of the cover glass is 1.11 mm, and the external voltage is 8.4V. The size and length-width ratio of the electric heating film layer sample are shown in Table 7 below.

[0167] Table 7

[0168] Sample number Length (mm) Width (mm) Length: width Area (mm 2 ) θ1 25 25 1 625 θ2 35.4 17.7 2 625 θ4 50 12.5 4 625

[0169] The sample was placed in a constant temperature and humidity cold and hot cycle test box and tested at -10°C, -20°C, and -40°C, respectively. The test results are shown in Table 8 below.

[0170] Table 8

[0171]

[0172] From the data in Table 8 above, it can be seen that at different ambient temperatures, the heating time is shortest when the length-width ratio θ = 1, but the heat required to heat to 1.5°C is usually higher, which is a reasonable phenomenon because the P / S ratio is higher. Similarly, when the P / S ratio is high, the final equilibrium temperature that can be reached at a fixed ambient temperature will also be the highest, for example, in a -10°C environment, the highest equilibrium temperature when θ = 1 is 87.8°C, as the length-width ratio increases, the P / S value also decreases, and the last equilibrium temperature reached is also reduced to 22.8°C when θ = 4. The same phenomenon also occurs in -20°C and -40°C environments.

[0173] The P / S value decreases, which affects the final equilibrium temperature. The final equilibrium temperature means the final equilibrium temperature of the outer surface of the cover plate under the condition of full opening of the voltage at a certain ambient temperature. The final equilibrium temperature must exceed the target temperature of the windshield glass, such as the target temperature of 1.5℃. If the final equilibrium temperature does not exceed 1.5℃, it means that the heating capacity of the electrothermal film layer cannot meet the deicing requirements of the windshield glass. From the data in Table 8 above, when the ambient temperature is -40℃, if θ=4, the final equilibrium temperature can only reach -6.4℃. That is, this is the highest temperature under the condition, and no matter how the electrothermal film layer cannot melt the ice on the outer surface of the cover plate. In other words, in an environment of -40℃, the P / S value of the electrothermal film layer is 2272W / m 2 Not enough to melt the ice layer. Therefore, the utility model controls the P / S at -40℃ to be not less than 3000W / m 2 , and controls the ratio of the length and width of each region in the plurality of regions separated by the electrothermal film layer to be 1-2.5, so that a better electric heating effect can be achieved. If the P / S and θ values are not within the range of the utility model, a good electric heating effect cannot be achieved.

[0174] Test Example 5: Electric heating property discussion ②: Effect of changing voltage on electric heating effect of electrothermal glass with same area but different length-width ratio under same ambient temperature

[0175] Similar to the test device in Test Example 4, but the ambient temperature is fixed at -40℃, and the voltage is increased to 3, which is 4.2V, 8.4V and 16.8V. The test results are shown in Table 9 below.

[0176] Table 9

[0177]

[0178] From the data in Table 9 above, it can be found that the only changed condition is the heating source voltage under the same glass combination and test environment. In an environment of -40℃, when the voltage is 4.2V, the P / S of θ=1, 2, 4 is 2272, 1136, 568. At this time, it can be found that the final equilibrium temperature is far below 1.5℃. That is, the voltage of 4.2V (P / S is less than 3000W / m 2) cannot provide enough energy to heat the cover glass, and naturally cannot achieve the effect of deicing the outer surface of the windshield glass. The case of 16.8V has been described in Test Example 4, which will not be repeated here. The case of 16.8V can be said to be opposite to that of 4.2V, and the P / S values at θ values of 1, 2, and 4 are 36359, 18180, and 9090, respectively. At this time, the P / S value is relatively high, and therefore the time required to raise the temperature from -40°C to 1.5°C is greatly reduced, and the temperature raising time at θ = 1 is only 49 seconds, which is a relatively short time for deicing the windshield of an aircraft. However, the advantage of short time temperature raising also increases another risk, as can be seen from the data in Table 9, the final equilibrium temperature is as high as 235°C, which is much higher than the softening point of the adhesive layer used in the windshield glass combination, which is harmful to the adhesive layer and needs to be avoided. Therefore, when a relatively high P / S value is used, a suitable thermal control system needs to be matched, whether it is on-off control or PID control, to ensure that the surface temperature of the glass cannot approach the tolerance temperature of the adhesive layer.

[0179] Test Example 6: Investigation of P / S value

[0180] As in the test device in Test Example 5, in an environment temperature of -40°C, the same glass plate thickness and structure combination, the same test environment, the same heating area, but the aspect ratio θ and the voltage can be changed, as in the data in Test Example 5, the P / S value and the highest equilibrium temperature are taken out and plotted for analysis, which can be obtained Figure 6 .

[0181] As can be seen from the curve in Figure 6 , as the P / S value increases, the final equilibrium temperature T max also gradually increases, and at this time a horizontal line is drawn at 1.5°C, it can be observed that the horizontal line and the curve approximately intersect at P / S = 3000. Therefore, at an environment temperature of -40°C, regardless of the voltage used by the electrothermal glass, the aspect ratio or the sheet resistance of the electrothermal film layer, the P / S value needs to be maintained greater than about 3000 W / m 2 , in order to heat the cover glass to 1.5°C, and also to achieve the deicing effect. This verifies that the P / S value controlled in the range of the present application achieves a good electrothermal effect. In addition, the larger the P / S value, the shorter the heating time, but the higher the final equilibrium temperature, at which time a temperature control system needs to be used to ensure that the surface of the cover glass remains at 1.5°C, and the temperature cannot continue to rise, causing damage to other materials in the windshield electrothermal glass.

[0182] Similarly, when the external environment temperature is lower than -40°C, for example -70°C, which is a temperature that can be encountered above 10,000 meters, the minimum P / S value will obviously be higher than 3000 W / m 2The minimum P / S value is greater than or equal to 3000W / m 2 @40℃, and the good electric heating effect is verified.

Claims

1. An electrothermal glass laminate, comprising: The first inorganic glass plate is located on the outer side, the second inorganic glass plate is placed opposite to the first inorganic glass plate, and the electrothermal film layer is located between the first inorganic glass plate and the second inorganic glass plate. The feature is that the electrothermal film layer is divided into several regions, and there are gaps between the regions; The gaps between the periphery of the first inorganic glass plate and the second inorganic glass plate and between the regions of the electrothermal film layer are joined by cold laser welding.

2. The electrothermal glass laminate according to claim 1, characterized in that, it is provided that... Let the total thickness of the first inorganic glass plate and the second inorganic glass plate be x0, and let the thickness of the first inorganic glass plate be x1. Then the value of R is 0.3 > R > 0.

05.

3. The electrothermal glass laminate according to claim 2, characterized in that, The thickness of the first inorganic glass plate is 1 to 3 mm.

4. The electrothermal glass laminate according to claim 1, characterized in that, The electric heating power density of each region separated by the electrothermal film layer, the area of ​​each region separated by the electrothermal film layer, the resistivity of the material of the electrothermal film layer, the thickness of the electrothermal film layer, and the ratio of the length to the width of each region separated by the electrothermal film layer satisfy the relationship expressed by the following formula and the following conditions: Where P is the electric heating power of each region separated by the electric heating film layer, in watts; S is the area of ​​each region separated by the electric heating film layer, in square meters; P / S represents the electric heating power density of each region separated by the electric heating film layer; U is the voltage applied to the electric heating film layer, in volts; θ is the ratio of the length to the width of each region separated by the electric heating film layer; R S R is the sheet resistance of the material of the electrothermal film, in ohms, and S =ρ / d, where ρ is the resistivity of the material of the electrothermal film layer, in ohm-meters; and d is the thickness of the electrothermal film layer, in meters. At -40℃, P / S is not less than 3000W / m. 2 .

5. The electrothermal glass laminate according to claim 4, characterized in that, When the total area of ​​the several regions separated by the electrothermal film layer is between 0.7 and 1.1 m² 2 At that time, S is 0.2–0.4 m. 2 .

6. The electrothermal glass laminate according to claim 4, characterized in that, The ratio of the length to the width of each of the several regions separated by the electrothermal film layer is 1 to 2.

5.

7. The electrothermal glass laminate according to claim 1, characterized in that, The width of the gap between the regions separated by the electrothermal film layer is 0.5 to 3.5 mm.

8. The electrothermal glass laminate according to claim 1, characterized in that, The thickness of the electrothermal film layer is less than 100 nm.

9. The electrothermal glass laminate according to claim 1, characterized in that, The material of the electrothermal film layer includes metals, inorganic metal oxides, or graphene.

10. The electrothermal glass laminate according to claim 1, characterized in that, The electrothermal glass laminate further includes conductive lines connected to the electrothermal film layer.

11. The electrothermal glass laminate according to claim 1, characterized in that, The first inorganic glass plate and the second inorganic glass plate respectively include chemically tempered glass plate, physically tempered glass plate or semi-tempered glass plate; The materials of the first inorganic glass plate and the second inorganic glass plate respectively include aluminosilicate glass, lithium aluminosilicate glass, borosilicate glass, borosilicate glass or soda-lime glass.

12. An electrothermal glass, comprising, from the outside to the inside: Outer electrothermal glass layer, first laminated layer, middle glass layer, second laminated layer and inner glass layer; The outer electrothermal glass layer is characterized in that it is an electrothermal glass laminate as described in any one of claims 1-11; The intermediate glass layer includes a third inorganic glass plate; The inner glass layer includes a fourth inorganic glass plate; The outer electrothermal glass layer, the first laminated layer, the middle glass layer, the second laminated layer, and the inner glass layer are combined into a whole.

13. The electrothermal glass according to claim 12, characterized in that, The thickness of the third inorganic glass plate is 7-15 mm; The thickness of the fourth inorganic glass plate is 4–12 mm.

14. The electrothermal glass according to claim 12, characterized in that, The third inorganic glass plate and the fourth inorganic glass plate respectively include chemically tempered glass plate, physically tempered glass plate or semi-tempered glass plate; The materials of the third and fourth inorganic glass plates respectively include aluminosilicate glass, lithium aluminosilicate glass, borosilicate glass, borosilicate glass, or soda-lime glass.

15. The electrothermal glass according to claim 12, characterized in that, The thickness of the first interlayer is 2.2–6.0 mm; The thickness of the second interlayer is 1.5–5.3 mm; The materials of the first and second interlayers include TPU, PVB, EVA or SGP, respectively.

16. The electrothermal glass according to claim 12, characterized in that, The shape of the electrothermal glass includes a flat surface, a single curved surface, a hyperboloid, or a spherical surface.

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