Ultra-high-performance energy-saving window based on high-transparency heat-preservation middle layer and preparation method thereof

Abstract

The invention discloses an ultra-high-performance energy-saving window based on a high-transparency heat-preservation middle layer and a preparation method of the ultra-high-performance energy-saving window, and belongs to the technical field of energy-saving windows.The ultra-high-performance energy-saving window mainly comprises outer-layer glass, inner-layer glass, at least two parallel glass panels and a hollow cavity sealed between the glass panels, and a high-transparency heat-insulating middle layer is arranged. When the thickness of the high-transparency heat-preservation middle layer is not larger than 3 mm, the transparent heat-preservation middle layer has winding flexibility and is convenient to transport and industrially lay and mount, and the laminating step of the transparent heat-preservation middle layer can be efficiently carried out like film laminating and is different from a traditional thick and heavy glass laminating process.

Description

Technical Field

[0001] This invention relates to the field of energy-saving window technology, specifically to an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer and its preparation method. Technical Background

[0002] With the continuous improvement of building energy efficiency standards, the demand for high-performance energy-saving windows is becoming increasingly urgent. Currently, the mainstream products on the market mainly include: Double / triple-pane insulated windows: These use air or inert gas (such as argon or krypton) interlayers for insulation. However, their insulation performance is limited by the thickness of the gas interlayer (usually requiring protection from convection, with an optimal thickness of approximately 12-16mm), leading to a bottleneck in further reducing the overall window's heat transfer coefficient (U-value). Low-E glass: In extremely cold regions, while the Low-E coating can reduce indoor heat radiation loss, it also blocks some short-wave solar radiation, hindering passive solar heat gain in winter. Vacuum-sealed windows: These utilize a vacuum layer for insulation, resulting in an extremely low U-value. However, they suffer from high manufacturing costs, a risk of slight air leakage, and the potential for minor light scattering due to the supporting structure. They also face the challenge of balancing insulation and light transmission. There is a type of window made of transparent thermal insulation material (TIM) that uses a single layer of insulation with low thermal conductivity (<26 mW / (K·m)) (such as cellulose-based materials) as an intermediate layer component, focusing on optimizing overall thermal insulation and light transmission through multi-layer structure and low refractive index materials.

[0003] Despite existing technological explorations, the following contradictions remain to be resolved in applications in cold and frigid regions where enhanced solar heat gain is crucial during winter: The contradiction between heat insulation and light transmission: Traditional Low-E glass, in order to maintain heat and reduce cold radiation, reflects some solar heat, reducing the precious solar heat gain in winter. The contradiction between performance and thickness: Achieving ultra-low U-values ​​(e.g., <1.0 W / (m²)) is challenging. 2 ·K)) often requires very thick gas-insulated layers or multi-layered glass, resulting in heavy windows, high requirements for profiles, and soaring costs. Material and application compatibility contradictions: Existing transparent insulation materials (such as some aerogels) may have problems such as low strength, difficulty in processing, and high cost. Their optical properties (such as haze) and mechanical properties (such as flexibility) may not be optimized for the balance between "customizable thin layers", "high light transmittance" and "easy installation". Summary of the Invention

[0004] The purpose of this invention is to provide an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer and its preparation method. The core of this invention is to use a transparent thermal insulation material with specific performance parameters as the interlayer, which achieves extremely high visible light transmittance while ensuring an ultra-low heat transfer coefficient. It particularly optimizes the net heat gain in winter under cold climates and has good processability and application adaptability.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] An ultra-high performance energy-saving window based on a high-transparency thermal insulation interlayer includes at least two parallel glass panels, an outer glass panel and an inner glass panel, and a hollow cavity sealed between the glass panels. A high-transparency thermal insulation interlayer is provided in the hollow cavity. The structure is simplified (e.g., double-glazed windows with a single interlayer can approach or achieve the thermal insulation effect of triple-glazed windows with two cavities), the weight is reduced, and the requirements for profiles and installation structures are lowered.

[0007] Furthermore, the thermal conductivity λ of the highly transparent thermal insulation interlayer is less than 0.026 W / (m·K); the visible light transmittance is greater than 80%; the thickness is 1-30 mm, and a thin layer can be customized while maintaining high light transmittance; when the thickness is not greater than 3 mm, the highly transparent thermal insulation interlayer has the flexibility to be rolled up, which facilitates transportation and industrial installation.

[0008] Furthermore, the highly transparent thermal insulation intermediate layer is a self-supporting layer, separated from the two glass panels by spacers to form two or more independent thin gas interlayers; or it is attached to the inner surface of one of the glass panels, forming a gas interlayer between it and the other glass panel. To avoid convection, the optimal thickness of the gas interlayer is about 12-16mm.

[0009] Furthermore, the material of the highly transparent thermal insulation intermediate layer is a uniform nanoporous material. Through material selection and process control, high light transmittance, low haze, and a certain mechanical strength are achieved while ensuring low thermal conductivity.

[0010] Furthermore, the average pore size of the highly transparent thermal insulation intermediate layer is less than 20-30% of the wavelength of visible light, in order to minimize light scattering.

[0011] Furthermore, a Low-E coating is applied to both the inner and outer glass layers. To maximize solar heat gain in frigid regions, a low-emissivity (Low-E) coating is selectively applied to the outer glass layer (outdoor side). High-efficiency heat insulation is achieved through a highly transparent and light-transmitting interlayer, replacing or reducing reliance on the Low-E coating and allowing more solar radiation to pass through directly, thus improving indoor heat gain in winter. A Low-E coating is selectively applied to the inner glass layer (indoor side) to control indoor long-wave radiation heat loss.

[0012] This invention also provides a method for preparing an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer, used to produce the aforementioned ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer, comprising the following steps: bonding the outer glass layer, inner glass layer, spacer strip, and highly transparent thermal insulation interlayer together; sealing along the perimeter to form a sealed gas interlayer; filling the gas interlayer with air, inert gas, or evacuating it to obtain an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer. By using a highly transparent thermal insulation interlayer, the thermal insulation limit of traditional gas interlayers is broken, achieving an ultra-high thermal insulation level with a relatively thinner total thickness, while maintaining high light transmittance, effectively solving the traditional contradiction between thermal insulation and light transmission.

[0013] Furthermore, the bonding method can be direct bonding, roll forming, or bonding with a transparent adhesive; for a rollable high-transparency thermal insulation interlayer with a thickness of no more than 3mm, this bonding step can be performed as efficiently as applying a film, unlike the traditional heavy glass lamination process.

[0014] Furthermore, the inert gas is argon or krypton. The inert gas can effectively slow down the heat convection in the intermediate layer, reduce the thermal conductivity of the gas, and improve the heat preservation performance of the energy-saving window.

[0015] Furthermore, the transparent adhesive is a pressure-sensitive adhesive, which, without damaging the bonding surface structure and ensuring the stability of the adhesive layer, also provides a relatively long bonding time, thus extending the service life of the energy-saving window.

[0016] Beneficial effects

[0017] Exceptional overall performance: By using a high-performance transparent insulation interlayer, the thermal insulation limit of traditional gas-insulated sandwich structures is broken, achieving a U-value of <1.0W / (m²) with a relatively thinner overall thickness. 2 It boasts an ultra-high heat insulation level of ·K while maintaining a high light transmittance of >80%, effectively resolving the traditional contradiction between heat insulation and light transmission.

[0018] Climate-adaptive innovation: For cold climate zones, the strategy of "high-transparency thermal insulation interlayer + selective use of Low-E coating" optimizes the solar thermal gain (SHGC) of the entire window, making the window a net heat gain component in winter, which is more in line with the needs of passive buildings and near-zero energy buildings.

[0019] Simplified Structure and Cost Potential: Compared to solutions that pursue an excessive number of glass layers (such as quad or pentaglaze), the structure of this invention may be simpler (e.g., a double-glazed structure with a single interlayer can approach or achieve the insulation effect of a triple-glazed structure with two cavities), reducing weight and lowering requirements for profiles and installation structures. The flexible, rollable interlayer facilitates automated production and large-scale application, and has the potential to reduce costs.

[0020] High application flexibility: The thickness of the intermediate layer can be customized (1-30mm), providing flexibility for designs with different performance requirements and installation space. Thin and flexible products are particularly suitable for retrofitting old windows or applications that are sensitive to thickness. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a double-glazed, ultra-low heat transfer coefficient energy-saving window structure.

[0022] Figure 2 A schematic diagram of a double-glazed energy-saving window with ultra-low heat transfer coefficient without a Low-E film;

[0023] Figure 3 The diagram shows a double-glazed energy-saving window with an ultra-low heat transfer coefficient and a Low-E film. In the diagram, a is an energy-saving window with a Low-E film on the outer glass and b is an energy-saving window with Low-E films on both the inner and outer glass.

[0024] Figure 4 The diagram shows a thin, high-transparency, heat-insulating, and energy-saving window structure. In the diagram, a is a schematic diagram of an energy-saving window structure with a high-transparency heat-insulating intermediate layer attached to the inner surface of the outer glass, and b is a schematic diagram of an energy-saving window structure with a high-transparency heat-insulating intermediate layer attached to the outer surface of the outer glass.

[0025] Figure 5 The diagram shows a thin, high-transmittance, heat-insulating, and energy-saving window structure without a Low-E film. In the diagram, a is a diagram of an energy-saving window structure with a high-transmittance heat-insulating intermediate layer attached to the inner surface of the inner glass, b is a diagram of an energy-saving window structure with a high-transmittance heat-insulating intermediate layer attached to the inner surface of the outer glass, and c is a diagram of an energy-saving window structure with a high-transmittance heat-insulating intermediate layer attached to the outer surface of the outer glass.

[0026] Figure 6 Schematic diagram of a double-glazed energy-saving window with an ultra-low heat transfer coefficient and an outer glass layer coated with a Low-E film;

[0027] Figure 7 This is a schematic diagram of an energy-saving window structure with a double high-transparency thermal insulation intermediate layer.

[0028] Reference numerals: 1. Outer glass; 2. High-transparency thermal insulation intermediate layer; 3. Inner glass; 4. Gas interlayer; 5. Low-E film; 6. Pressure-sensitive adhesive. Specific Implementation

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

[0030] Example 1

[0031] use Figure 1The structure is shown. Both the outer glass layer 1 and the inner glass layer 3 are 4mm ultra-clear tempered glass, with a Low-E film 5 applied to the inner glass. A highly transparent insulating interlayer 2, consisting of a self-supporting layer of high-transparency insulating material, is used in the middle. Its thermal conductivity is 0.018 W / (m·K), visible light transmittance is 88%, and haze is 1.5%. A gas interlayer 4 is formed between the highly transparent insulating interlayer and each of the inner and outer glass layers. Performance calculation / expectation: Through thermal calculations, the heat transfer coefficient (K-value) of this glass assembly is expected to reach 0.8 W / (m·K). 2 At temperatures below 1000 K, the visible light transmittance (VT) can be maintained above 75%. Because the outer glass is not coated with a Low-E film, the solar heat gain coefficient (SHGC) is expected to reach above 0.6, making it ideal for use in extremely cold regions.

[0032] Example 2

[0033] use Figure 2 The structure is shown. Both the outer glass layer 1 and the inner glass layer 3 are 4mm ultra-clear tempered glass. A highly transparent insulating intermediate layer 2, with a thermal conductivity of 0.018 W / (m·K), a visible light transmittance of 88%, and a haze of 1.5%, is used as a self-supporting layer. A gas interlayer 4 is formed between the highly transparent insulating intermediate layer and each of the inner and outer glass layers. Performance calculation / expectation: Since neither the inner nor outer glass layers have a Low-E film, the infrared radiation blocking capability of this structure is relatively weak. Through thermal calculations, its heat transfer coefficient (K value) is expected to be between 1.0 and 1.2 W / (m·K). 2 The visible light transmittance (VT) is maintained at a high level of around 80%, thanks to the ultra-clear glass and highly transparent intermediate layer. Meanwhile, the solar heat gain coefficient (SHGC) is expected to reach over 0.7. While this solution is weaker in insulation performance than Example 1, it boasts higher light transmittance and SHGC, making it suitable for cold regions with high requirements for lighting and solar energy acquisition, and less stringent insulation requirements.

[0034] Example 3

[0035] use Figure 3 The structure shown. Both the outer glass layer 1 and the inner glass layer 3 are 4mm ultra-clear tempered glass. The outer glass layer is fitted with a Low-E film 5. Figure 3 The inner glass layer a does not have a Low-E film, while the inner glass layer b has a Low-E film. A highly transparent insulating interlayer 2, with a thermal conductivity of 0.018 W / (m·K), a visible light transmittance of 88%, and a haze of 1.5%, serves as a self-supporting layer. A gas interlayer 4 is formed between the highly transparent insulating interlayer and each of the inner and outer glass layers. Performance calculations / expectations:

[0036] Figure 3Option a (only the outer layer has a Low-E film): In this configuration, the Low-E film primarily reflects long-wave radiation from the outside, resulting in higher thermal resistance. Its K-value is expected to reach 0.7-0.9 W / (m²). 2 (K). Since the Low-E film is located on the outdoor side, it has a significant effect on blocking solar infrared rays, and its SHGC is expected to be between 0.4 and 0.5, making it suitable for areas with hot summers and cold winters or where shading is required. The visible light transmittance (VT) is affected by the Low-E film and is expected to be around 75%.

[0037] Figure 3 Middle b (both inner and outer layers have Low-E films): The dual Low-E film configuration significantly enhances radiation blocking capability. Its K value is expected to be as low as 0.6-0.8 W / (m²). 2 At ·K), the thermal insulation performance is optimal. However, at the same time, SHGC will be further reduced to about 0.3-0.4, and visible light transmittance (VT) may also drop to about 70%. This solution is suitable for buildings in extremely cold or hot regions with extremely high requirements for thermal insulation and low requirements for natural lighting and solar heat gain.

[0038] Example 4

[0039] use Figure 4 The structure is shown. To reduce the overall thickness, two 3mm thick ordinary float glass sheets are used as the outer glass layer 1 and the inner glass layer 3, respectively. A 2mm thick flexible, highly transparent, heat-insulating interlayer 2 (thermal conductivity 0.022W / (m·K), light transmittance 85%, haze 2%, rollable) is directly bonded to the surface of the outer glass layer using an optically transparent pressure-sensitive adhesive 6, and a Low-E film 5 is applied to the surface of the inner glass layer. A gas interlayer 4 with a total thickness of 12mm is formed between the inner and outer glass layers for encapsulation.

[0040] The total thickness of this window can be controlled to within 20mm, similar to that of traditional single-pane windows, making it easy to replace old windows. While ensuring high light transmittance, its K-value is expected to be superior to that of traditional double-glazed windows (12mm air gap), reaching approximately 1.2-1.5W / (m²). 2 The K-value is expected to be 1.2-1.5 W / (m²), and it has the potential for even better performance after upgrading to argon filling. The bonding process of the flexible interlayer is simple and efficient. Performance calculation / expectation: This design, by placing the Low-E film on the inner surface of the inner glass layer, and combining it with the gas interlayer and interlayer, achieves both thinness and heat insulation. 2The K-value is significantly superior to traditional double-glazed windows (K-value approximately 2.7-3.0). Due to the use of ordinary float glass and lamination technology, the visible light transmittance (VT) is expected to be between 70-75%. The Low-E film effectively reflects indoor heat on the inside, with an expected SHGC level of moderate (approximately 0.5-0.6). The total thickness is controlled within 20mm, facilitating energy-saving retrofits of existing building windows.

[0041] Example 5

[0042] use Figure 5 The structure is shown. To reduce the overall thickness, two 3mm thick ordinary float glass sheets are used as the outer glass layer 1 and the inner glass layer 3, respectively. A 2mm thick flexible, highly transparent insulating interlayer 2 (thermal conductivity 0.022W / (m·K), light transmittance 85%, haze 2%, rollable) is directly bonded to the glass surface using an optically transparent pressure-sensitive adhesive 6. A gas interlayer 4 with a total thickness of 12mm is formed between the inner and outer glass layers for encapsulation. Performance calculation / expectation: This structure is a simplified version of Example 4, without any Low-E film. Its insulation performance mainly depends on the gas interlayer and the interlayer, therefore the K value is expected to be relatively high, approximately 1.6-1.8W / (m·K). 2 (·K). However, its advantages lie in its lower cost and, due to the absence of a membrane layer, higher visible light transmittance (VT is expected to reach over 78%) and solar heat gain coefficient (SHGC is expected to reach over 0.65). It is suitable for scenarios with general requirements for thermal insulation performance but seeking high light transmittance, low cost, and easy installation (such as sunrooms, enclosed balconies, etc.).

[0043] Example 6

[0044] use Figure 6 The structure is shown. To reduce the overall thickness, two 3mm thick ordinary float glass sheets are used as the outer glass layer 1 and the inner glass layer 3, respectively. A 2mm thick flexible, highly transparent, heat-insulating interlayer 2 (thermal conductivity 0.022W / (m·K), light transmittance 85%, haze 2%, rollable) is directly bonded to the glass surface using an optically transparent pressure-sensitive adhesive 6, and a Low-E film 5 is placed on the outer glass surface. A gas interlayer 4 with a total thickness of 12mm is formed between the inner and outer glass layers for encapsulation. Performance calculation / expectation: In this structure, the Low-E film is placed on the first surface (outer surface of the outer glass), and its main function is to reflect outdoor solar radiation heat. Its K value is expected to be similar to that of Example 4, approximately 1.3-1.5W / (m·K). 2(·K). However, the SHGC is relatively low, expected to be between 0.4 and 0.5, providing excellent shading and heat insulation effects and effectively reducing the air conditioning load in summer. The visible light transmittance (VT) is affected by the outer Low-E layer and is expected to be around 70%. It is particularly suitable for building facades or skylights in areas with hot summers and warm winters or hot summers and cold winters, focusing on summer shading.

[0045] Example 7

[0046] use Figure 7 The structure is shown. To further improve the thermal insulation performance of the window, two 3mm thick ordinary float glass sheets can be used as the outer glass layer 1 and the inner glass layer 3, respectively. Two 5mm thick high-transparency thermal insulation interlayers 2 (thermal conductivity 0.022W / (m·K), light transmittance 85%, haze 2%) are used as the interlayer. Three 12mm thick gas sandwich layers 4 are formed between the inner and outer glass sheets and the high-performance thermal insulation interlayer for encapsulation. Performance calculation / expectation: By increasing the number of interlayers and gas sandwich layers, a four-layer, three-cavity high-performance structure is formed. Although ordinary glass and interlayer materials with slightly higher thermal conductivity are used, the multiple insulation structures significantly increase its overall thermal resistance. Its K value is expected to be as low as 0.6W / (m·K). 2 Below 1000 K, it meets the standard requirements for ultra-low energy buildings such as passive houses. Correspondingly, due to multi-layer interface reflection and material absorption, its visible light transmittance (VT) will decrease, expected to be between 65-70%. The solar heat gain coefficient (SHGC) is also low, expected to be approximately 0.3-0.4. This solution pursues ultimate thermal insulation performance and is suitable for buildings in extremely cold regions or those with extremely high requirements for indoor environmental stability.

[0047] Table 1. Performance Summary and Comparison of Various Embodiments

[0048]

Claims

1. A high-performance energy-saving window based on a highly transparent thermal insulation interlayer, comprising at least two parallel glass panels, an outer glass panel and an inner glass panel, and a hollow cavity sealed between the glass panels, characterized in that, One or more highly transparent thermal insulation intermediate layers are provided inside the hollow cavity.

2. The ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 1, characterized in that, The thermal conductivity λ of the highly transparent thermal insulation intermediate layer is less than 0.026 W / (m·K); the visible light transmittance is greater than 80%; and the thickness is 1-30 mm.

3. The ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 1, characterized in that, The highly transparent thermal insulation interlayer is a self-supporting layer, separated from the two glass panels by spacers to form two or more independent thin gas interlayers; or it is attached to the inner surface of one of the glass panels to form a gas interlayer between it and the other glass panel.

4. The ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 1, characterized in that, The material of the highly transparent thermal insulation intermediate layer is a uniform nanoporous material.

5. The ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 1, characterized in that, The average pore size of the highly transparent thermal insulation intermediate layer is less than 20-30% of the wavelength of visible light.

6. The ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 1, characterized in that, The outer and inner glass layers are coated with Low-E coatings.

7. A method for preparing an ultra-high performance energy-saving window with a highly transparent thermal insulation interlayer according to any one of claims 1 to 6, comprising the following steps: The outer glass layer, inner glass layer, spacer strip, and high-transparency thermal insulation intermediate layer are bonded together. By sealing the perimeter to form a sealed gas interlayer, and filling the gas interlayer with air, inert gas, or by evacuating, an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer is prepared.

8. The method for preparing an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 7, characterized in that, The bonding method is direct bonding, rolling, or bonding with a transparent adhesive.

9. The method for preparing an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 7, characterized in that, The inert gas is argon or krypton.

10. The method for preparing an ultra-high performance energy-saving window based on a highly transparent thermal insulation interlayer according to claim 8, characterized in that, The transparent adhesive is a pressure-sensitive adhesive.

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