Technology for enhancing transmittance of antireflection coated panel glass

Abstract

The invention discloses a technology for enhancing transmittance of antireflection coated panel glass. The technology comprises the following steps: cleaning impurities such as oil stains and glass powder on the surface of glass; preheating: preheating the surface of the glass, enabling the water temperature of a cleaning machine to reach more than 60 DEG C, enabling the temperature of an air box to reach more than 60 DEG C, and enabling the transmittance of a finished product photovoltaic coated glass produced in an environment with relative humidity to be shown; the transmittance of the finished photovoltaic coated glass obtained in a low-humidity environment in a range of 450-950 is obviously higher than that of the finished photovoltaic coated glass obtained in a high-humidity environment.

Description

Technical Field

[0001] The present invention relates to the technical field of silicon-based solar cells, and in particular to a process for enhancing the transmittance of anti-reflective coated panel glass. Background Art

[0002] Silicon-based solar cells are the most mature photovoltaic devices in the current photovoltaic market, and photovoltaic-coated glass is a key component. Since the band gap of silicon-based photovoltaic materials is 1.11.3 eV and the absorption onset is between 1000 and 1100 nm, photovoltaic-coated glass must have a sufficiently high transmittance within the 400 nm to 1100 nm range to ensure that more sunlight is absorbed by the silicon. There are many methods to improve the performance of photovoltaic cover glass, including: reducing the iron content in the original glass to reduce the absorption of light by iron ions; embossing the cover glass to improve the reflection and scattering path of light between the glass and the silicon plate, thereby increasing the silicon plate's light absorption; and coating the photovoltaic glass to utilize the principle of destructive interference to reduce its reflection of sunlight and improve its utilization rate.

[0003] Currently, different coating solutions and coating processes in the photovoltaic industry significantly impact the transmittance of finished photovoltaic coated glass. However, relative humidity has received relatively little attention. After entering the tempering furnace, water molecules on the film's surface are difficult to evaporate. After tempering, the presence of water prevents the micropores on the film's surface from completely closing, leaving a small number of micropores on the surface of the finished photovoltaic coated glass. After cleaning in the packaging and washing machine and exposure to room-temperature water, the coated glass surface fogs and absorbs moisture, resulting in a decrease in transmittance. This defect primarily manifests as a whitening of the surface under reflected light and severe fogging under transmitted light.

[0004] Comparing electron micrographs of coated glass after and after the packaging and cleaning process reveals that the porous silica structure is intact before the packaging and cleaning process. However, without heating, holes appear in the porous silica. Analysis reveals that this is due to the low water temperature during the packaging and cleaning process, which causes moisture absorption and delays in evaporation. This results in a smeared surface and low transmittance. Therefore, a process for enhancing the transmittance of anti-reflective coated panel glass is urgently needed to address these issues. Summary of the Invention

[0005] The purpose of the present invention is to provide a process for enhancing the transmittance of anti-reflective coated panel glass. This technology is the influence of relative air humidity on the morphology and transmittance of finished photovoltaic coated glass. To further improve the transmittance of photovoltaic coated glass, relative air humidity must be regarded as an important key process control point.

[0006] By installing a water heating system in the packaging washing machine to increase the water temperature to above 60 degrees, and a wind heating system to heat it to above 60 degrees, the coated glass surface will not fog or get wet. Through deep processing, mass production and terminal data statistics of component factories, the coating yield rate can reach ≥99% and the transmittance can reach ≥94.7% ( Figure 1 ), which fully meets the product requirements.

[0007] When using ultra-clear float glass as the substrate for coated panels, the water temperature is adjusted by adjusting the packaging and washing machine and adding a water heating system, and an air heating system is installed to adjust the temperature process control requirements, so as to enhance the transmittance of the ultra-clear float photovoltaic panel glass and basically eliminate the above-mentioned defects.

[0008] In order to achieve the above object, the present invention provides the following technical solutions: A process for enhancing transmittance of anti-reflective coated panel glass comprises the following steps: A1 cleaning, cleaning oil stains, glass powder and other impurities on the glass surface; A2 preheating, preheating the glass surface, temperature range: room temperature - 60 ℃; A3: The coating liquid is evenly applied to the surface of the photovoltaic glass by a roller, usually the air side; A4 one-step solidification: bake and solidify the film on the glass surface. The temperature range is from room temperature to 300℃. A5 second plating, in which the coating liquid is evenly applied to the surface of the photovoltaic glass by a roller, usually the air side; A6 secondary curing, baking and curing the film on the glass surface, temperature range: room temperature to 300℃; A7 tempering, put into the tempering furnace for tempering, the temperature during tempering is 700℃; A8 cleaning, put it into the cleaning machine for cleaning, clean the oil, glass powder and other impurities on the glass surface, water heating temperature: room temperature -100℃, wind heating temperature: room temperature -200℃, operation mode: 24 hours continuous operation; A9 inspection is to conduct full inspection or random inspection on the coated products according to the process requirements, mainly checking the performance, film surface, YT difference and other items.

[0009] Preferably, in said A2, after preheating, said A2 further comprises a connection, said connection comprises glass being passed to the next device through a connection, wherein a sheet storage table is provided for emergency processing; said glass is positioned after being connected, and the position is corrected, said positioning comprises coarse positioning and fine positioning, Rough positioning: adjust the position of both sides of the glass in the previous process to ensure it is centered; Precise positioning: adjust the front, back, left and right positions to meet production needs.

[0010] Preferably, the preheating furnace temperature during A2 preheating is: the preheating temperature is 20-150°C, and the plate temperature of the rubber feed roller is 30°C for the best effect.

[0011] Preferably, in A3 and A5, the temperature of the coating room is controlled at 25±8°C, with 23°C being the best; and the humidity is controlled at 30%-65%, with 48% being the best.

[0012] 5. Preferably, in the A3 plating, the coating speed is ≥5.5 pieces / min, and the gas source is ≥0.45 MPa.

[0013] Preferably, the A4 is solidified in a curing furnace at a temperature of 50°C-150°C.

[0014] In the A5, the coating speed is ≥5.5 pieces / min, and the gas source is ≥0.45 MPa.

[0015] In the A6, the temperature of the second curing furnace is 100°C-200°C.

[0016] Preferably, in the A8, four water tanks are used for separate circulation spraying, wherein the water temperature is 60°C-100°C and the wind heating is 60°C-80°C.

[0017] In the above technical solution, the present invention provides a process for enhancing the transmittance of anti-reflective coated panel glass. The water temperature of the packaging and washing machine reaches above 60°C, the temperature of the wind box reaches above 60°C, and the transmittance of the finished photovoltaic coated glass produced in an environment with relative humidity is as follows: Figure 3 As shown by Figure 3 It can be seen that the transmittance of the finished photovoltaic coated glass obtained under low humidity conditions is significantly higher in the 450°C to 950°C range than that obtained under high humidity, covering nearly the entire visible light range. Only in the near-infrared region is the transmittance slightly lower than that of the finished photovoltaic coated glass obtained under high humidity. This may be due to the rougher surface of the film layer of the finished photovoltaic coated glass obtained under high humidity. The longer wavelengths of the near-infrared region result in more reflections on the glass surface, resulting in increased transmittance in the long-wavelength range. The average transmittance of the finished photovoltaic coated glass obtained under low humidity conditions is 0.1% higher than that of the finished photovoltaic coated glass under high humidity conditions, which means that the gain is 0.1 higher on average. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0019] Figure 1A schematic diagram of transmittance curves of finished photovoltaic coated glass under different relative air humidities provided in an embodiment of a process for enhancing transmittance of anti-reflective coated panel glass according to the present invention.

[0020] Figure 2 A test chart provided for an embodiment of the process for enhancing transmittance of an anti-reflective coated panel glass according to the present invention.

[0021] Figure 3 Schematic diagram of an electron microscope image of coated glass that has not passed through a packaging and cleaning machine, provided in an embodiment of the present invention for enhancing the transmittance of an anti-reflective coated panel glass.

[0022] Figure 4 This is an electron microscope image of coated glass that has passed through a packaging and cleaning machine, provided in an embodiment of the present invention for a process for enhancing transmittance of anti-reflective coated panel glass. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0024] like Figure 1-4 As shown, an embodiment of the present invention provides a process for enhancing transmittance of an anti-reflective coated panel glass, comprising the following steps: A1 cleaning, cleaning oil stains, glass powder and other impurities on the glass surface; A2 preheating, preheating the glass surface, temperature range: room temperature - 60 ℃; A3: The coating liquid is evenly applied to the surface of the photovoltaic glass by a roller, usually the air side; A4 one-step solidification: bake and solidify the film on the glass surface. The temperature range is from room temperature to 300℃. A5 second plating, in which the coating liquid is evenly applied to the surface of the photovoltaic glass by a roller, usually the air side; A6 secondary curing, baking and curing the film on the glass surface, temperature range: room temperature to 300℃; A7 tempering, put into the tempering furnace for tempering, the temperature during tempering is 700℃; A8 cleaning, put it into the cleaning machine for cleaning, clean the oil, glass powder and other impurities on the glass surface, water heating temperature: room temperature -100℃, wind heating temperature: room temperature -200℃, operation mode: 24 hours continuous operation; A9 inspection is to conduct full inspection or random inspection on the coated products according to the process requirements, mainly checking the performance, film surface, YT difference and other items.

[0025] Preferably, in said A2, after preheating, said A2 further comprises a connection, said connection comprises glass being passed to the next device through a connection, wherein a sheet storage table is provided for emergency processing; said glass is positioned after being connected, and the position is corrected, said positioning comprises coarse positioning and fine positioning, Rough positioning: adjust the position of both sides of the glass in the previous process to ensure it is centered; Precise positioning: adjust the front, back, left and right positions to meet production needs.

[0026] Preferably, the preheating furnace temperature during A2 preheating is: the preheating temperature is 20-150°C, and the plate temperature of the rubber feed roller is 30°C for the best effect.

[0027] Preferably, in A3 and A5, the temperature of the coating room is controlled at 25±8°C, with 23°C being the best; and the humidity is controlled at 30%-65%, with 48% being the best.

[0028] 5. Preferably, in the A3 plating, the coating speed is ≥5.5 pieces / min, and the gas source is ≥0.45 MPa.

[0029] Preferably, the A4 is solidified in a curing furnace at a temperature of 50°C-150°C.

[0030] In the A5, the coating speed is ≥5.5 pieces / min, and the gas source is ≥0.45 MPa.

[0031] In the A6, the temperature of the second curing furnace is 100°C-200°C.

[0032] Preferably, in the A8, four water tanks are used for separate circulation spraying, wherein the water temperature is 60°C-100°C and the wind heating is 60°C-80°C.

[0033] Example 1 Cleaning machine: cleans oil, glass powder and other impurities on the glass surface Main parameters: Cleaning glass thickness: 1.6-4.0mm Disc brush: 2 sets (4 rows) Wind Blades: 5 pairs Water supply system: 3 water tanks with separate circulation spraying Air filtration (level): coarse, medium, high efficiency Maximum line speed: 18m / min Glass deviation: ≤10mm Operation mode: 24 hours continuous operation Preheating furnace: preheating the glass surface and raising the temperature Main parameters: Line speed: 8-18m / min Temperature range: room temperature - 60℃ Maximum conveying width: 1400mm Total length: 2800m Connection: The glass is transferred to the next device through the connection, where a storage table is set up for emergency treatment; Main parameters: Line speed: adjustable according to production rhythm Production abnormality: Press the emergency stop switch Storage quantity: ≤35 pieces Stop position: adjustable front and back Coating positioning section: glass positioning, position correction Main parameters: Rough positioning: adjust the position of both sides of the glass in the previous process to ensure it is centered Precision positioning: adjust the front, back, left, and right positions to meet production needs Coating machine: The coating liquid is evenly applied to the surface of photovoltaic glass (usually the air side) through a roller Main parameters: Processing thickness: 1.6-4.0mm Conveying direction: short side first Coating speed: ≥5.5 pieces / min (calculated based on 2.0mm-1000x2000mm) Coating yield rate: ≥99% Maximum coating size: 1400x2500mm Minimum coating size: 300x300mm Air source: ≥0.45Mpa (clean compressed air) A coating curing furnace: bake the film on the glass surface and cure it Main parameters: Line speed: 8-18m / min Temperature range: room temperature--300℃ Maximum conveying width: 1550mm Heating device: IR medium wave tube Number of sections: heating section + cooling section Total length: 15400mm Coating machine: The coating liquid is evenly applied to the surface of photovoltaic glass (usually the air side) through a roller Main parameters: Processing thickness: 1.6-4.0mm Conveying direction: short side first Coating speed: ≥5.5 pieces / min (calculated based on 2.0mm-1000x2000mm) Coating yield rate: ≥99.% Maximum coating size: 1400x2500mm Minimum coating size: 300x300mm Air source: ≥0.45Mpa (clean compressed air) Secondary coating and curing furnace: bake the film on the glass surface and cure it Main parameters: Line speed: 8-18m / min Temperature range: room temperature--300℃ Maximum conveying width: 1550mm Heating device: IR medium wave tube Total length: 8000mm Cleaning machine: cleans oil, glass powder and other impurities on the glass surface Main parameters: Cleaning glass thickness: 1.6-4.0mm Brushes: 4 pairs Wind Blades: 8 pairs Water supply system: 4 water tanks with separate circulation spraying Maximum line speed: 38m / min Glass deviation: ≤10mm Water heating temperature: room temperature--100℃ Wind heating temperature: room temperature - 200℃ Operation mode: 24 hours continuous operation Inspection: Full inspection or random inspection of the coated products according to the process requirements, mainly inspecting performance, film surface, YT difference and other items; This technical solution mainly involves rolling glass substrates and developing a new coating production process technology for the first time, which realizes the enhanced transmittance of rolled glass. The glass coating panel products meet the application of solar photovoltaic power station panels, making the photoelectric conversion rate better, and its performance transmittance is an excellent indicator of more than 94.4%.

[0034] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A process for enhancing transmittance of anti-reflective coated panel glass, characterized in that: The following steps are involved: A1 cleaning, cleaning oil stains, glass powder and other impurities on the glass surface; A2 preheating, preheating the glass surface, temperature range: room temperature - 60 ℃; A3: The coating liquid is evenly applied to the surface of the photovoltaic glass by a roller, usually the air side; A4 one-step solidification: bake and solidify the film on the glass surface. The temperature range is from room temperature to 300℃. A5 second plating, in which the coating liquid is evenly applied to the surface of the photovoltaic glass by a roller, usually the air side; A6 secondary curing, baking and curing the film on the glass surface, temperature range: room temperature to 300℃; A7 tempering, put into the tempering furnace for tempering, the temperature during tempering is 700℃; A8 cleaning, put it into the cleaning machine for cleaning, clean the oil, glass powder and other impurities on the glass surface, water heating temperature: room temperature -100℃, wind heating temperature: room temperature -200℃, operation mode: 24 hours continuous operation; A9 inspection is to conduct full inspection or random inspection on the coated products according to the process requirements, mainly checking the performance, film surface, YT difference and other items.

2. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: In the A2, after the preheating, the A2 also includes a connection, the connection includes the glass being passed to the next device through the connection, wherein a storage table is provided for emergency processing; after the glass is connected, positioning and position correction are performed, the positioning includes coarse positioning and fine positioning, Rough positioning: adjust the position of both sides of the glass in the previous process to ensure it is centered; Precise positioning: adjust the front, back, left and right positions to meet production needs.

3. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: A2 preheating furnace temperature: preheating temperature is 20-150℃, and the plate temperature of the rubber roller is 30℃ for best effect.

4. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: In A3 and A5, the temperature of the coating room is controlled at 25±8°C, with 23°C being the best; the humidity is controlled at 30%-65%, with 48% being the best.

5. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: During the A3 plating, the coating speed is ≥5.5 pieces / min, and the gas source is ≥0.45 MPa.

6. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: The A4 solidification process has a curing furnace temperature of 50°C to 150°C.

7. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: In the A5, the coating speed is ≥5.5 pieces / min, and the gas source is ≥0.45 MPa.

8. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: In the A6, the temperature of the second curing furnace is 100°C-200°C.

9. The process for enhancing transmittance of anti-reflective coated panel glass according to claim 1, characterized in that: In the A8, four water tanks are used for separate circulation spraying, wherein the water temperature is 60°C-100°C and the wind heating is 60°C-80°C.

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