Curved-surface special-shaped multifunctional integrally-formed laminated glass and preparation method thereof

Abstract

The invention relates to the technical field of glass, in particular to curved-surface special-shaped multifunctional integrally-formed laminated glass which comprises an outer curved-surface glass plate, an inner curved-surface glass plate and an inner curved-surface glass plate, the inner curved surface glass plate has a second preset curvature matched with the first preset curvature; the at least one functional film layer is arranged between the outer curved glass plate and the inner curved glass plate, and the functional film layer is selected from one or more of a dimming film and a photovoltaic cell film; the first adhesive film layer and the second adhesive film layer are respectively positioned on two sides of the functional film layer and are used for bonding the outer curved glass plate, the functional film layer and the inner curved glass plate; wherein at least one of the outer curved glass plate and the inner curved glass plate is subjected to strengthening treatment through a low-temperature ion exchange process, and the surface stress ranges from 410 MPa to 1000 MPa. The technical problems that in the prior art, the curved surface adaptability and the strengthening effect are insufficient are solved. The invention correspondingly provides a preparation method of the curved-surface special-shaped multifunctional integrally-formed laminated glass.

Description

Technical Field

[0001] This invention relates to the field of glass technology, and in particular to a curved, irregularly shaped, multifunctional, integrally molded laminated glass and its preparation method. Background Technology

[0002] Laminated glass has been widely used in many fields such as architectural decoration, automobile manufacturing, and electronic product displays due to its excellent safety performance, optical performance, and diverse functional characteristics. Traditional laminated glass usually consists of two layers of flat glass and an intermediate functional film layer and adhesive film layer. This structure meets basic usage requirements to a certain extent. However, as various industries continue to increase their requirements for product appearance design and functional integration, the application of curved and irregularly shaped laminated glass is becoming more and more common.

[0003] Furthermore, with the continuous development of technology, people's functional requirements for laminated glass are no longer limited to basic light transmission and safety protection, but rather they hope to integrate more advanced functions, such as dimming and photovoltaic power generation. For example, Chinese Patent Publication No. CN117153917A discloses a curved photovoltaic laminated glass, its preparation method, and a vehicle. The aforementioned curved photovoltaic laminated glass includes: an outer curved glass, a first encapsulant layer, a second encapsulant layer, a photovoltaic cell, a third encapsulant layer, and an inner curved glass. Both the first and second encapsulant layers are disposed between the outer curved glass and the photovoltaic cell, with the first encapsulant layer closer to the outer curved glass than the second encapsulant layer. The third encapsulant layer is disposed between the photovoltaic cell and the inner curved glass. The interface between the first and second encapsulant layers has a textured surface.

[0004] In various applications, laminated glass may be subjected to external impacts, temperature changes, and other factors. If the glass strength is insufficient, it is prone to breakage. Traditional glass strengthening processes, such as physical tempering, can improve the strength of glass to some extent, but for curved glass, especially thin curved glass, physical tempering has many drawbacks.

[0005] In summary, traditional laminated glass currently on the market has many shortcomings in terms of surface adaptability and strengthening effect, making it difficult to meet the urgent needs of modern industries for high-performance, curved, irregularly shaped, multifunctional, one-piece molded laminated glass. Therefore, developing a curved, irregularly shaped, multifunctional, one-piece molded laminated glass with good surface adaptability and excellent strengthening effect is of significant practical importance. Summary of the Invention

[0006] Therefore, to address the aforementioned problems, this invention proposes a curved, irregularly shaped, multifunctional, integrally molded laminated glass, which solves the technical problems of insufficient surface adaptability and strengthening effect in the prior art. A corresponding method for preparing the curved, irregularly shaped, multifunctional, integrally molded laminated glass is also proposed.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a curved, irregularly shaped, multifunctional, integrally molded laminated glass, comprising:

[0008] The outer curved glass panel has a first preset curvature and a thickness of 1.6 mm to 5.0 mm;

[0009] The inner curved glass plate has a second preset curvature that matches the first preset curvature and a thickness of 0.1 mm to 1.2 mm.

[0010] At least one functional film layer is disposed between the outer curved glass plate and the inner curved glass plate, wherein the functional film layer is selected from one or more of dimming film and photovoltaic cell film;

[0011] The first adhesive film layer and the second adhesive film layer are located on both sides of the functional film layer, respectively, and are used to bond the outer curved glass plate, the functional film layer and the inner curved glass plate.

[0012] Wherein, at least one of the outer curved glass plate and the inner curved glass plate is strengthened by a low-temperature ion exchange process, and the surface stress is 410MPa to 1000MPa. After strengthening, the surface compressive stress distribution of the inner curved glass plate satisfies the following conditions:

[0013] a. The surface compressive stress difference Δσ ≤ 50 MPa, where Δσ = Δσ max -Δσ min , Δσ max Δσ represents the maximum compressive stress on the surface. min This represents the minimum compressive stress value on the surface.

[0014] b. The surface compressive stress gradient G along the radial direction of the inner curved glass plate is ≤10MPa / mm, where G=|Δσ0 / ΔL|, ΔL is the distance between two points measured along the radial direction, and Δσ0 is the compressive stress difference between the corresponding two points;

[0015] c. The surface compressive stress value of the edge area within ≤5mm of the edge of the reinforced inner curved glass plate is Δσ. e The surface compressive stress value of the reinforced inner curved glass plate within a range of ≤50% of the maximum radius from the center is Δσ. c The ratio satisfies: 0.8 ≤ Δσ e / Δσ c ≤1.2;

[0016] d. The standard deviation Δσ of compressive stress in any 10mm × 10mm area on the surface of the inner curved glass plate is measured using a stress polarizer. std ≤15MPa.

[0017] Furthermore, the functional film layer is a dimming film, comprising:

[0018] The thickness of both the first substrate layer and the second substrate layer does not exceed 100 μm;

[0019] A first transparent electrode layer and a second transparent electrode layer are respectively disposed between a first substrate layer and a second substrate layer;

[0020] A liquid crystal layer is disposed between a first transparent electrode layer and a second transparent electrode layer;

[0021] The first substrate layer and the second substrate layer have a glass transition temperature of not less than 130°C, and the curvature of the dimming film is matched with that of the outer curved glass plate or the inner curved glass plate by a thermoforming process above the glass transition temperature.

[0022] Furthermore, the functional film layer is a photovoltaic cell film, which includes:

[0023] Photovoltaic cell unit, selected from silicon-based cells and thin-film cells;

[0024] The first adhesive film layer, located on the light-receiving side of the photovoltaic cell unit, is made of transparent hot melt adhesive film with a thickness of 0.2mm to 1.0mm;

[0025] The second adhesive film layer, located on the back side of the photovoltaic cell unit, is made of highly water-resistant POE material and has a thickness of 0.2mm to 1.0mm.

[0026] The first and second adhesive film layers are hot-pressed together using a laminator at 120℃~150℃ and 0.1MPa~0.5MPa pressure to completely encapsulate the photovoltaic cell unit, forming a sandwich structure.

[0027] The contact surfaces of the first adhesive film layer and the second adhesive film layer are bonded together by hot melt bonding.

[0028] The interface between the first and second adhesive film layers has a textured surface to increase light scattering and reflection, thereby improving the power generation efficiency of the photovoltaic cells.

[0029] The raised and recessed textures include any one or more of the following: pyramidal, conical, semi-circular, and hemispherical.

[0030] Furthermore, it also includes: an edge sealing layer, which is set around the outer curved glass plate and the inner curved glass plate to prevent moisture and dust from entering the interior of the interlayer;

[0031] The edge sealing layer uses a hot-melt sealant, which is applied to the edge of the laminated glass after being heated and melted to form a continuous sealing strip.

[0032] A method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass based on the same inventive concept includes the following steps:

[0033] S1. Glass plate pretreatment: High-temperature hot bending treatment is carried out on the outer curved glass plate, with the bending temperature between its annealing upper limit temperature Ta and softening point Tf.

[0034] The inner curved glass plate is subjected to low-temperature cold bending treatment, with the bending temperature below its transition point temperature Tg, and a first ion exchange strengthening treatment is carried out during or after the cold bending process to form a surface compressive stress layer.

[0035] S2. Functional film layer pretreatment: Surface flatness detection and damage repair of the functional film layer are carried out to ensure that its surface is flat and undamaged.

[0036] S3. Stacking and assembly: The outer curved glass plate, the first adhesive film layer, the functional film layer, the second adhesive film layer and the inner curved glass plate are stacked in sequence to form the structure to be formed;

[0037] S4. Low-temperature pressure molding: The structure to be molded is placed in a vacuum environment with a vacuum degree not exceeding 50Pa. A pressure of 10kPa to 100kPa is applied by a cold pressing device, and the molding temperature is 80℃ to 380℃.

[0038] During the molding process, a vacuum is continuously applied to remove air bubbles from the molten adhesive layer.

[0039] S5. Post-processing: When the functional film layer is a photovoltaic cell film, after pressure molding, heat preservation treatment is carried out for 0.5 hours to 4 hours to ensure full adhesion between the layers.

[0040] Furthermore, in step S1, the low-temperature cold bending rate is controlled between 0.5° / s and 5° / s to reduce microcracks generated during the bending process;

[0041] After cold bending, the inner curved glass plate is immersed in a mixed solution containing potassium ions and sodium ions, wherein the mass ratio of potassium ions to sodium ions is 3:1 to 5:1, to carry out multi-gradient ion exchange.

[0042] The ion exchange temperature is controlled in stages: the first stage is 350℃ to 400℃ for 20 to 60 minutes, and the second stage is 420℃ to 450℃ for 5 to 15 minutes, forming a double-layer compressive stress structure that transitions between the high-stress zone on the surface and the low-stress zone on the subsurface.

[0043] The cooling method adopts a staged air cooling system, with the first stage having an air velocity of 2m / s to 5m / s and the second stage having an air velocity of 0.5m / s to 2m / s, in order to avoid glass breakage caused by sudden stress changes.

[0044] Furthermore, the pretreatment of the inner curved glass plate also includes:

[0045] After the first ion exchange strengthening, the inner curved glass plate is forcibly bent to the first preset curvature, and a second ion exchange strengthening is performed in the forced bending state.

[0046] The inner curved glass plate is immersed in a mixed solution containing potassium ions and lithium ions, wherein the mass ratio of potassium ions to lithium ions is 2:1 to 4:1, the exchange temperature is 380℃ to 420℃, and the time is 10 minutes to 30 minutes.

[0047] Through the deep diffusion of lithium ions, a high-modulus strengthening layer is formed on the subsurface of the glass, which works in conjunction with the surface compressive stress layer formed by the first strengthening to improve the bending fatigue resistance of the glass by more than 30%.

[0048] Release the forced bending structure to obtain an inner curved glass plate with a second preset curvature, wherein the radius of curvature deviation between the second preset curvature and the first preset curvature is less than 0.5%, and it is coordinated with the curvature of the outer curved glass plate.

[0049] Furthermore, the surface compressive stress formed by the first ion exchange is 500 MPa to 700 MPa, and the subsurface stress gradient is 10 MPa / μm to 20 MPa / μm.

[0050] The second ion exchange forms a high-modulus strengthening layer on the subsurface, with an elastic modulus E≥80GPa, which makes the stress distribution of the glass more uniform under bending conditions and reduces the local maximum stress by more than 40%.

[0051] The potassium ion diffusion depth of the first ion exchange is 15 μm to 25 μm, and the lithium ion diffusion depth of the second ion exchange is 30 μm to 50 μm. The two are superimposed to form a gradient stress buffer layer.

[0052] Furthermore, when the functional film layer is a photovoltaic cell film, the post-processing step further includes:

[0053] After lamination and assembly and before pressure molding, the overall structure is preheated. The preheating temperature does not exceed the melting temperature of the adhesive film layer in order to reduce stress concentration during the molding process.

[0054] After thermal insulation, the laminated glass is sealed at the edges to prevent moisture from seeping in and causing the functional film to fail.

[0055] Furthermore, both the outer curved glass plate and the inner curved glass plate are chemically tempered glass and meet the following performance requirements:

[0056] The surface compressive stress of the curved glass plate is ≥700MPa, and the ion exchange depth is ≥20μm.

[0057] The surface compressive stress of the inner curved glass plate is ≥500MPa, and the ion exchange depth is ≥15μm.

[0058] The overall light transmittance of laminated glass is ≥65%.

[0059] Furthermore, the cold pressing equipment used in the low-temperature pressure molding step includes:

[0060] The first mold is used to shape the outer curved glass plate to a preset curvature;

[0061] The second mold is used to shape the inner curved glass plate to a preset curvature and cooperate with the first mold to form the overall curvature of the laminated glass.

[0062] In this process, at least one of the first mold and the second mold is heated at a temperature of 80°C to 380°C, and the heating method is selected from electric heating, oil circulation heating or infrared heating.

[0063] By adopting the aforementioned technical solution, the beneficial effects of the present invention are:

[0064] 1. Both the outer and inner curved glass panels have specific curvature and thickness ranges, which can meet the needs of different curved and irregular designs, expanding application scenarios. Functional films are selected from one or more of dimming films and photovoltaic cell films, endowing the laminated glass with diverse functions such as dimming or power generation. The glass panels are strengthened through a low-temperature ion exchange process, improving glass strength and impact resistance, and enhancing safety. Multiple conditions are proposed for the surface compressive stress distribution of the strengthened inner curved glass panel to ensure uniform stress on the glass surface, reducing the risk of breakage due to uneven stress, and improving the stability and reliability of the glass.

[0065] 2. When the functional film layer is a dimming film, the first and second substrate layers are thin and have high glass transition temperatures, which facilitates the thermoforming process to give the dimming film a curvature that matches the glass plate, ensuring the applicability of the dimming film in curved structures. The structural design of the dimming film controls the liquid crystal layer through a transparent electrode layer to achieve dimming functionality, meeting the light adjustment needs of different scenarios.

[0066] 3. When the functional film layer is a photovoltaic cell film, the selection of photovoltaic cell materials should be clearly defined, providing multiple options to adapt to different power generation efficiency and cost requirements. The first and second encapsulant layers use different materials and thicknesses. The first encapsulant layer is transparent, facilitating light entry into the photovoltaic cell, while the second encapsulant layer has high water resistance, protecting the cell and improving the stability and lifespan of the photovoltaic cell film. The two encapsulant layers are fused together under specific conditions to form a sandwich structure that completely encapsulates the photovoltaic cell, ensuring good sealing and structural stability. Textured surfaces are added at the interface between the two encapsulant layers to increase light scattering and reflection, thereby improving the power generation efficiency of the photovoltaic cell.

[0067] 4. An edge sealing layer is installed to effectively prevent moisture and dust from entering the interlayer, protecting the functional film layer, avoiding functional failure due to environmental factors, and extending the service life of the laminated glass. A hot-melt sealant is used, and a continuous sealing strip is formed by heating and melting the sealant, resulting in good sealing performance and a simple and feasible process.

[0068] 5. In the glass pretreatment process, high-temperature hot bending is used for outward-curved glass sheets, and low-temperature cold bending is used for inward-curved glass sheets for strengthening. Different treatment methods are employed to adapt to the different characteristics of the glass sheets, ensuring bending quality and strengthening effect. Functional film pretreatment ensures a smooth and undamaged surface, improving the quality of subsequent lamination assembly and the performance of the finished product. The lamination assembly steps clearly define the order of each layer to ensure structural stability. Low-temperature pressure forming is carried out in a vacuum environment with continuous vacuuming to remove air bubbles, improve forming quality, and reduce defects. The post-treatment step involves heat preservation treatment for the photovoltaic cell film to ensure full adhesion of each layer and improve the overall performance of the laminated glass.

[0069] 6. Controlling the low-temperature cold bending rate reduces micro-cracks generated during bending, improving the quality of the inner curved glass sheet. Multi-gradient ion exchange and staged control of ion exchange temperature create a double-layer compressive stress structure, enhancing glass strength and impact resistance. Graded air cooling avoids sudden stress changes that could cause glass breakage, ensuring the quality of glass forming.

[0070] 7. After the first ion exchange strengthening, the inner curved glass plate is forcibly bent and then undergoes a second ion exchange strengthening. A high-modulus strengthening layer is formed through deep lithium ion diffusion, which, in conjunction with the surface compressive stress layer, significantly improves the glass's resistance to bending fatigue and extends its service life. Releasing the forced bending structure results in an inner curved glass plate with a curvature that matches the outer curved glass plate, ensuring overall curvature matching of the laminated glass and improving structural stability and appearance quality.

[0071] 8. By clearly defining the stress parameters formed by the first and second ion exchanges and the elastic modulus of the high-modulus strengthening layer, the stress distribution of the glass under bending conditions becomes more uniform, and the local maximum stress is significantly reduced, further improving the glass's bending resistance and reliability. The diffusion depths of potassium and lithium ions are specified to form a gradient stress buffer layer, effectively buffering stress and reducing stress concentration damage to the glass.

[0072] 9. When the functional film layer is a photovoltaic cell film, preheating treatment should be performed after lamination and assembly and before pressure molding to reduce stress concentration during molding, improve molding quality, and avoid damage to the functional film layer due to stress. After heat preservation treatment, edge sealing treatment should be performed to prevent moisture penetration that could cause functional film layer failure, further protecting the performance of the photovoltaic cell film.

[0073] 10. Specify the surface compressive stress and ion exchange depth of the outer and inner curved glass panels to ensure the strength and impact resistance of the glass and meet safety requirements. Require the overall light transmittance of the laminated glass to ensure that it does not impede light transmission while fulfilling other functions, thus meeting the needs of applications requiring high light transmittance.

[0074] 11. In the low-temperature pressure molding step, the cold pressing equipment is equipped with a first mold and a second mold to respectively form the outer and inner curved glass plates, which work together to form the overall curvature, ensuring molding accuracy and curvature matching. At least one mold is heated during the molding process, and multiple heating methods are available for selection. The heating method can be flexibly adjusted according to the actual situation to improve molding efficiency and quality. Attached Figure Description

[0075] Figure 1 This is a schematic diagram of the structure of the present invention.

[0076] Figure 2 This is a cross-sectional structural diagram of the present invention.

[0077] Figure 3 This is a cross-sectional view of the dimming film.

[0078] Figure 4 This is a schematic diagram of the structure of the present invention with an edge sealing layer.

[0079] Figure 5 This is a schematic flowchart of the preparation method of the present invention.

[0080] Figure label:

[0081] 1. Outer curved glass plate; 2. Inner curved glass plate; 3. Functional film layer; 4. First adhesive film layer; 5. Second adhesive film layer; 6. Edge sealing layer; 31. First substrate layer; 32. Second substrate layer; 33. First transparent electrode layer; 34. Second transparent electrode layer; 35. Liquid crystal layer. Detailed Implementation

[0082] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments.

[0083] refer to Figures 1 to 4 This embodiment provides a curved, irregularly shaped, multifunctional, one-piece molded laminated glass, comprising:

[0084] The outer curved glass plate 1 has a first preset curvature and a thickness of 1.6 mm to 5.0 mm;

[0085] The inner curved glass plate 2 has a second preset curvature that matches the first preset curvature, and a thickness of 0.1 mm to 1.2 mm;

[0086] At least one functional film layer 3 is disposed between the outer curved glass plate 1 and the inner curved glass plate 2, wherein the functional film layer 3 is selected from one or more of dimming film and photovoltaic cell film;

[0087] The first adhesive film layer 4 and the second adhesive film layer 5 are located on both sides of the functional film layer 3, respectively, and are used to bond the outer curved glass plate 1, the functional film layer 3 and the inner curved glass plate 2.

[0088] Wherein, at least one of the outer curved glass plate 1 and the inner curved glass plate 2 is strengthened by a low-temperature ion exchange process, and the surface stress is 410MPa to 1000MPa. After strengthening, the surface compressive stress distribution of the inner curved glass plate 2 satisfies the following conditions:

[0089] a. The surface compressive stress difference Δσ ≤ 50 MPa, where Δσ = Δσ max -Δσ min , Δσ max Δσ represents the maximum compressive stress on the surface. min This represents the minimum compressive stress value on the surface; it limits the size of the range and ensures that the compressive stress distribution on the inner curved glass surface is relatively uniform. If the range is too large, it means that the stress is too concentrated in some areas of the glass surface, while the stress is smaller in other areas. When subjected to external forces, the stress concentration areas are prone to become weak points, leading to glass breakage and reducing the overall strength and safety of the glass.

[0090] b. The surface compressive stress gradient G along the radial direction of the inner curved glass plate should be ≤10 MPa / mm, where G = |Δσ0 / ΔL|, ΔL is the distance between two points measured radially, and Δσ0 is the difference in compressive stress between the corresponding two points. Limiting the stress gradient ensures that the stress change of the inner curved glass plate is gradual in the radial direction. If the stress gradient is too large, it indicates that the stress change of the glass is drastic in the radial direction. When subjected to external force, the area with large stress change is prone to stress concentration, thus affecting the impact resistance and service life of the glass.

[0091] c. The surface compressive stress value of the edge area within ≤5mm of the edge of the reinforced inner curved glass plate is Δσ. e The surface compressive stress value of the reinforced inner curved glass plate within a range of ≤50% of the maximum radius from the center is Δσ. c The ratio satisfies: 0.8 ≤ Δσ e / Δσ c ≤1.2; where 50% of the maximum radius refers to 50% of the radius of the largest circle defined by the curved glass. If the ratio is too small, it indicates that the stress in the edge area is much less than that in the center area, and the edge is likely to become a weak point in the glass; if the ratio is too large, it may indicate abnormal stress in the center area, which will also affect the overall performance of the glass.

[0092] d. The standard deviation Δσ of compressive stress in any 10mm × 10mm area on the surface of the inner curved glass plate is measured using a stress polarizer. std ≤15MPa. Limiting the standard deviation ensures the uniformity of compressive stress distribution in localized areas of the inner curved glass surface. If the standard deviation is too large, it indicates that the stress distribution in that area is dispersed, with some areas exhibiting excessively high or low stress, which will affect the mechanical and optical properties of the glass, reducing its quality and reliability.

[0093] Preferably, when the functional film layer 3 is a dimming film, it includes: a first substrate layer 31 and a second substrate layer 32, both with a thickness not exceeding 100 μm; a first transparent electrode layer 33 and a second transparent electrode layer 34, respectively disposed between the first substrate layer 31 and the second substrate layer 32; and a liquid crystal layer 35 disposed between the first transparent electrode layer 33 and the second transparent electrode layer 34; wherein, the glass transition temperature of the first substrate layer 31 and the second substrate layer 32 is not lower than 130°C, and the dimming film is given a curvature matching the outer curved glass plate 1 or the inner curved glass plate 2 by a thermoforming process above the glass transition temperature.

[0094] Preferably, when the functional film layer 3 is a photovoltaic cell film, the photovoltaic cell film includes: a photovoltaic cell unit, selected from silicon-based cells and thin-film cells; a first adhesive film layer 4, located on the light-receiving side of the photovoltaic cell unit, made of transparent hot melt adhesive film with a thickness of 0.2mm to 1.0mm; a second adhesive film layer 5, located on the back-lighting side of the photovoltaic cell unit, made of high water-resistant POE material with a thickness of 0.2mm to 1.0mm; the first adhesive film layer 4 and the second adhesive film layer 5 are hot-pressed together by a laminator at 120℃ to 150℃ and 0.1MPa to 0.5MPa pressure to completely encapsulate the photovoltaic cell unit, forming a sandwich structure; the contact surfaces of the first adhesive film layer 4 and the second adhesive film layer 5 are bonded by hot melt bonding; wherein, a textured surface is provided at the interface between the first adhesive film layer 4 and the second adhesive film layer 5 to increase light scattering and reflection, thereby improving the power generation efficiency of the photovoltaic cell; the textured surface includes any one or more of pyramid, cone, semi-circular, and hemispherical shapes.

[0095] Of course, functional membrane layer 3 can also be other conventional functional membranes.

[0096] It also includes: an edge sealing layer 6, which is disposed around the outer curved glass plate 1 and the inner curved glass plate 2 to prevent moisture and dust from entering the interior of the interlayer; the edge sealing layer 6 is made of hot melt sealant, which is applied to the edge of the laminated glass after being heated and melted to form a continuous sealing strip.

[0097] See again Figure 5 A method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass based on the same inventive concept includes the following steps:

[0098] S1. Glass plate pretreatment: The outer curved glass plate 1 is subjected to high-temperature hot bending treatment, with the bending temperature between its annealing upper limit temperature Ta and softening point Tf; the inner curved glass plate 2 is subjected to low-temperature cold bending treatment, with the bending temperature below its transformation point temperature Tg, and the first ion exchange strengthening treatment is carried out during or after the cold bending process to form a surface compressive stress layer.

[0099] S2. Pretreatment of functional film layer 3: Surface flatness detection and damage repair are carried out on functional film layer 3 to ensure that its surface is flat and undamaged.

[0100] S3. Stacking and assembly: Stack the outer curved glass plate 1, the first adhesive film layer 4, the functional film layer 3, the second adhesive film layer 5 and the inner curved glass plate 2 in sequence to form the structure to be formed;

[0101] S4. Low-temperature pressure molding: The structure to be molded is placed in a vacuum environment with a vacuum degree not exceeding 50Pa. A pressure of 10kPa to 100kPa is applied by a cold pressing device, and the molding temperature is 80℃ to 380℃. During the molding process, vacuum is continuously drawn to remove air bubbles from the molten adhesive layer.

[0102] S5. Post-processing: When the functional film layer 3 is a photovoltaic cell film, after pressure molding, it is subjected to heat preservation treatment for 0.5 hours to 4 hours to ensure full adhesion between the layers.

[0103] In step S1, the low-temperature cold bending rate is controlled between 0.5° / s and 5° / s to reduce microcracks generated during the bending process;

[0104] After cold bending, the inner curved glass plate 2 is immersed in a mixed solution containing potassium ions and sodium ions, wherein the mass ratio of potassium ions to sodium ions is 3:1 to 5:1, to carry out multi-gradient ion exchange.

[0105] The ion exchange temperature is controlled in stages: the first stage is 350℃ to 400℃ for 20 to 60 minutes, and the second stage is 420℃ to 450℃ for 5 to 15 minutes, forming a double-layer compressive stress structure that transitions between the high-stress zone on the surface and the low-stress zone on the subsurface.

[0106] The cooling method adopts a staged air cooling system, with the first stage having an air velocity of 2m / s to 5m / s and the second stage having an air velocity of 0.5m / s to 2m / s, in order to avoid glass breakage caused by sudden stress changes.

[0107] The pretreatment of the inner curved glass plate 2 also includes:

[0108] After the first ion exchange strengthening, the inner curved glass plate 2 is forcibly bent to the first preset curvature, and a second ion exchange strengthening is performed in the forced bending state.

[0109] The inner curved glass plate 2 is immersed in a mixed solution containing potassium ions and lithium ions, wherein the mass ratio of potassium ions to lithium ions is 2:1 to 4:1, the exchange temperature is 380℃ to 420℃, and the time is 10 minutes to 30 minutes. Through the deep diffusion of lithium ions, a high modulus strengthening layer is formed on the subsurface of the glass, which works in conjunction with the surface compressive stress layer formed by the first strengthening to improve the bending fatigue resistance of the glass by more than 30%. The forced bending structure is released to obtain an inner curved glass plate 2 with a second preset curvature, wherein the radius of curvature deviation between the second preset curvature and the first preset curvature is less than 0.5%, and it works in conjunction with the curvature of the outer curved glass plate 1.

[0110] The surface compressive stress formed by the first ion exchange is 500 MPa to 700 MPa, and the subsurface stress gradient is 10 MPa / μm to 20 MPa / μm. The high-modulus strengthening layer formed by the second ion exchange in the subsurface has an elastic modulus E ≥ 80 GPa, which makes the stress distribution of the glass more uniform under bending conditions and reduces the local maximum stress by more than 40%. The potassium ion diffusion depth of the first ion exchange is 15 μm to 25 μm, and the lithium ion diffusion depth of the second ion exchange is 30 μm to 50 μm. The two are superimposed to form a gradient stress buffer layer.

[0111] When the functional film layer 3 is a photovoltaic cell film, the post-processing step further includes:

[0112] After lamination and assembly and before pressure molding, the overall structure is preheated. The preheating temperature does not exceed the melting temperature of the adhesive film layer to reduce stress concentration during molding. After heat preservation, the laminated glass is edge-sealed to prevent moisture penetration and failure of the functional film layer 3.

[0113] Both the outer curved glass plate 1 and the inner curved glass plate 2 are chemically tempered glass and meet the following performance requirements: the surface compressive stress of the outer curved glass plate 1 is ≥700MPa and the ion exchange depth is ≥20μm; the surface compressive stress of the inner curved glass plate 2 is ≥500MPa and the ion exchange depth is ≥15μm; the overall light transmittance of the laminated glass is ≥65%.

[0114] The cold pressing equipment used in the low-temperature pressure forming step includes: a first mold for forming the outer curved glass plate 1 to a preset curvature; and a second mold for forming the inner curved glass plate 2 to a preset curvature, which cooperates with the first mold to form the overall curvature of the laminated glass. At least one of the first and second molds is heated during the forming process at a temperature of 80°C to 380°C, and the heating method is selected from electric heating, oil circulation heating, or infrared heating. This cold pressing equipment is conventional in the art and will not be described in detail here.

[0115] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A curved, irregularly shaped, multifunctional, one-piece molded laminated glass, characterized in that, include: The outer curved glass panel has a first preset curvature and a thickness of 1.6 mm to 5.0 mm; The inner curved glass plate has a second preset curvature that matches the first preset curvature and a thickness of 0.1 mm to 1.2 mm. At least one functional film layer is disposed between the outer curved glass plate and the inner curved glass plate, wherein the functional film layer is selected from one or more of dimming film and photovoltaic cell film; The first adhesive film layer and the second adhesive film layer are located on both sides of the functional film layer, respectively, and are used to bond the outer curved glass plate, the functional film layer and the inner curved glass plate. Wherein, at least one of the outer curved glass plate and the inner curved glass plate is strengthened by a low-temperature ion exchange process, and the surface stress is 410MPa to 1000MPa. After strengthening, the surface compressive stress distribution of the inner curved glass plate satisfies the following conditions: a. The surface compressive stress difference Δσ ≤ 50 MPa, where Δσ = Δσ max -Δσ min , Δσ max Δσ represents the maximum compressive stress on the surface. min This represents the minimum compressive stress value on the surface. b. The surface compressive stress gradient G along the radial direction of the inner curved glass plate is ≤10MPa / mm, where G=|Δσ0 / ΔL|, ΔL is the distance between two points measured along the radial direction, and Δσ0 is the compressive stress difference between the corresponding two points; c. The surface compressive stress value of the edge area within ≤5mm of the edge of the reinforced inner curved glass plate is Δσ. e The surface compressive stress value of the reinforced inner curved glass plate within a range of ≤50% of the maximum radius from the center is Δσ. c The ratio satisfies: 0.8 ≤ Δσ e / Δσ c ≤1.2; d. The standard deviation Δσ of compressive stress in any 10mm × 10mm area on the surface of the inner curved glass plate is measured using a stress polarizer. std ≤15MPa.

2. The curved, irregularly shaped, multifunctional, one-piece molded laminated glass according to claim 1, characterized in that, The functional film layer is a dimming film, comprising: The thickness of both the first substrate layer and the second substrate layer does not exceed 100 μm; A first transparent electrode layer and a second transparent electrode layer are respectively disposed between a first substrate layer and a second substrate layer; A liquid crystal layer is disposed between a first transparent electrode layer and a second transparent electrode layer; The first substrate layer and the second substrate layer have a glass transition temperature of not less than 130°C, and the curvature of the dimming film is matched with that of the outer curved glass plate or the inner curved glass plate by a thermoforming process above the glass transition temperature.

3. The curved, irregularly shaped, multifunctional, one-piece molded laminated glass according to claim 1, characterized in that, The functional film layer is a photovoltaic cell film, and the photovoltaic cell film includes: Photovoltaic cell unit, selected from silicon-based cells and thin-film cells; The first adhesive film layer, located on the light-receiving side of the photovoltaic cell unit, is made of transparent hot melt adhesive film with a thickness of 0.2mm to 1.0mm; The second adhesive film layer, located on the back side of the photovoltaic cell unit, is made of highly water-resistant POE material and has a thickness of 0.2mm to 1.0mm. The first and second adhesive film layers are hot-pressed together using a laminator at 120℃~150℃ and 0.1MPa~0.5MPa pressure to completely encapsulate the photovoltaic cell unit, forming a sandwich structure. The contact surfaces of the first adhesive film layer and the second adhesive film layer are bonded together by hot melt bonding. The interface between the first and second adhesive film layers has a textured surface to increase light scattering and reflection, thereby improving the power generation efficiency of the photovoltaic cells. The raised and recessed textures include any one or more of the following: pyramidal, conical, semi-circular, and hemispherical.

4. The curved, irregularly shaped, multifunctional, one-piece molded laminated glass according to claim 1, characterized in that, Also includes: An edge sealing layer is installed around the outer curved glass plate and the inner curved glass plate to prevent moisture and dust from entering the interlayer. The edge sealing layer uses a hot-melt sealant, which is applied to the edge of the laminated glass after being heated and melted to form a continuous sealing strip.

5. A method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass, applied to the curved, irregularly shaped, multifunctional, integrally molded laminated glass according to claim 1, characterized in that, Includes the following steps: S1. Glass plate pretreatment: High-temperature hot bending treatment is carried out on the outer curved glass plate, with the bending temperature between its annealing upper limit temperature Ta and softening point Tf. The inner curved glass plate is subjected to low-temperature cold bending treatment, with the bending temperature below its transition point temperature Tg, and a first ion exchange strengthening treatment is carried out during or after the cold bending process to form a surface compressive stress layer. S2. Functional film layer pretreatment: Surface flatness detection and damage repair of the functional film layer are carried out to ensure that its surface is flat and undamaged. S3. Stacking and assembly: The outer curved glass plate, the first adhesive film layer, the functional film layer, the second adhesive film layer and the inner curved glass plate are stacked in sequence to form the structure to be formed; S4. Low-temperature pressure molding: The structure to be molded is placed in a vacuum environment with a vacuum degree not exceeding 50Pa. A pressure of 10kPa to 100kPa is applied by a cold pressing device, and the molding temperature is 80℃ to 380℃. During the molding process, a vacuum is continuously applied to remove air bubbles from the molten adhesive layer. S5. Post-processing: When the functional film layer is a photovoltaic cell film, after pressure molding, heat preservation treatment is carried out for 0.5 hours to 4 hours to ensure full adhesion between the layers.

6. The method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass according to claim 5, characterized in that, In step S1, the low-temperature cold bending rate is controlled between 0.5° / s and 5° / s to reduce microcracks generated during the bending process; After cold bending, the inner curved glass plate is immersed in a mixed solution containing potassium ions and sodium ions, wherein the mass ratio of potassium ions to sodium ions is 3:1 to 5:1, to carry out multi-gradient ion exchange. The ion exchange temperature is controlled in stages: the first stage is 350℃ to 400℃ for 20 to 60 minutes, and the second stage is 420℃ to 450℃ for 5 to 15 minutes, forming a double-layer compressive stress structure that transitions between the high-stress zone on the surface and the low-stress zone on the subsurface. The cooling method adopts a staged air cooling system, with the first stage having an air velocity of 2m / s to 5m / s and the second stage having an air velocity of 0.5m / s to 2m / s, in order to avoid glass breakage caused by sudden stress changes.

7. The method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass according to claim 6, characterized in that, The pretreatment of the inner curved glass plate also includes: After the first ion exchange strengthening, the inner curved glass plate is forcibly bent to the first preset curvature, and a second ion exchange strengthening is performed in the forced bending state. The inner curved glass plate is immersed in a mixed solution containing potassium ions and lithium ions, wherein the mass ratio of potassium ions to lithium ions is 2:1 to 4:1, the exchange temperature is 380℃ to 420℃, and the time is 10 minutes to 30 minutes. Through the deep diffusion of lithium ions, a high-modulus strengthening layer is formed on the subsurface of the glass, which works in conjunction with the surface compressive stress layer formed by the first strengthening to improve the bending fatigue resistance of the glass by more than 30%. Release the forced bending structure to obtain an inner curved glass plate with a second preset curvature, wherein the radius of curvature deviation between the second preset curvature and the first preset curvature is less than 0.5%, and it is coordinated with the curvature of the outer curved glass plate.

8. The method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass according to claim 7, characterized in that, The surface compressive stress formed by the first ion exchange is 500 MPa to 700 MPa, and the subsurface stress gradient is 10 MPa / μm to 20 MPa / μm. The second ion exchange forms a high-modulus strengthening layer on the subsurface, with an elastic modulus E≥80GPa, which makes the stress distribution of the glass more uniform under bending conditions and reduces the local maximum stress by more than 40%. The potassium ion diffusion depth of the first ion exchange is 15 μm to 25 μm, and the lithium ion diffusion depth of the second ion exchange is 30 μm to 50 μm. The two are superimposed to form a gradient stress buffer layer.

9. The method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass according to claim 5, characterized in that, When the functional film layer is a photovoltaic cell film, the post-processing step further includes: After lamination and assembly and before pressure molding, the overall structure is preheated. The preheating temperature does not exceed the melting temperature of the adhesive film layer in order to reduce stress concentration during the molding process. After thermal insulation, the laminated glass is sealed at the edges to prevent moisture from seeping in and causing the functional film to fail.

10. The method for preparing a curved, irregularly shaped, multifunctional, integrally molded laminated glass according to claim 5, characterized in that, Both the outer curved glass plate and the inner curved glass plate are chemically tempered glass and meet the following performance requirements: The surface compressive stress of the curved glass plate is ≥700MPa, and the ion exchange depth is ≥20μm. The surface compressive stress of the inner curved glass plate is ≥500MPa, and the ion exchange depth is ≥15μm. The overall light transmittance of laminated glass is ≥65%.

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