Hydrophilic-hydrophobic double-sided synchronous processing device and method for solar photovoltaic backboard

Abstract

The invention provides a hydrophilic-hydrophobic double-sided synchronous treatment device and method for a solar photovoltaic backplane, the device comprises a conveying mechanism, a hydrophilic treatment module and a hydrophobic treatment module, the conveying mechanism is used for conveying the photovoltaic backplane, and the hydrophilic treatment module is distributed on one side of the conveying mechanism and is used for carrying out hydrophilic treatment on one side of the photovoltaic backplane; the hydrophobic treatment module is distributed on the other side of the conveying mechanism and used for conducting hydrophobic treatment on the other face of the photovoltaic back plate. The conveying mechanism comprises a plurality of conveying modules, a hollow gap is formed between every two adjacent conveying modules, and the hydrophilic treatment modules / hydrophobic treatment modules conduct hydrophilic / hydrophobic treatment on the photovoltaic backboards through the gaps. The invention further provides an application method of the device. According to the invention, through a set of integrated plasma reaction system, hydrophilic modification of the inner side surface of the backboard and hydrophobic coating deposition of the outer side surface are synchronously realized, one-step efficient modification of the photovoltaic backboard is completed, the working efficiency and the product quality are improved, and the device is clean and environment-friendly.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of solar photovoltaic module manufacturing, and particularly relates to a solar photovoltaic backboard hydrophilic-hydrophobic double-sided synchronous processing device and method. BACKGROUND

[0002] The solar photovoltaic backboard is a key encapsulation material of the photovoltaic module, located at the outermost layer of the module, and mainly functions to protect the battery piece from the erosion of environmental factors such as water vapor, oxygen, and ultraviolet light. The commonly used backboard substrates such as polyethylene terephthalate (PET) and polyvinylidene fluoride (PVDF) often cannot meet the requirements of high reliability encapsulation in terms of surface properties. In order to improve the long-term weather resistance and encapsulation reliability of the photovoltaic module, different surface treatments are usually required for the two sides of the backboard: the inner side (the side combined with the EVA sealing adhesive film), which needs to have high surface energy and excellent adhesion, i.e. hydrophilicity, to ensure a firm and bubble-free tight combination with the EVA adhesive film during the lamination process, preventing delamination; the outer side (the side exposed to the environment), which needs to have low surface energy and excellent water repellency, i.e. hydrophobicity, to effectively inhibit the penetration of water vapor in the environment and improve the weather resistance of the module, such as anti-humidity and anti-PID (potential induced degradation).

[0003] There are already researches on the surface modification of solar photovoltaic backboards in the prior art. For example: Patent “Waterproof PET film for photovoltaic backboard and preparation method thereof” (CN119751939A) prepares a PET film with excellent anti-aging, flame-retardant, self-repairing, waterproof, and mechanical properties through modification of talc powder, functionalization of polysiloxane, treatment of flame-retardant monomers, and full-fluorooctyl ethylene. However, the preparation process of this technical solution involves multiple chemical modifications and complex reaction steps, and the process flow is complicated, which requires high purity of raw materials and control of reaction conditions, and is not conducive to large-scale industrial production and cost control. Patent “Photovoltaic coating, preparation method and application thereof” (CN120648270A) develops a photovoltaic coating containing modified hydrophilic silica, nano-magnesium fluoride, nano-tin dioxide, and other components, which is coated on the surface of photovoltaic glass and solidified to form a functional coating. However, the use of nano-materials in this technical solution can lead to uneven dispersion, resulting in fluctuations in coating thickness and affecting performance consistency. Moreover, the use of ethylenediamine and glacial acetic acid in the modification process may pose a chemical residue risk, and the long-term environmental safety needs to be verified. Patent “Preparation method of PET composite film” (CN120816736A) improves the interlayer adhesion, dimensional stability, and water vapor barrier performance of photovoltaic encapsulation modules by processes such as corona treatment of the PET film surface, coating of PVB adhesive containing specific silane coupling agents, and hot pressing and drying. However, this technical solution involves complicated processes such as hot pressing and drying, and only improves the bonding between PET and the encapsulation adhesive film, but cannot improve the hydrophobicity of PET.

[0004] In summary, the current traditional production process has obvious deficiencies. ① Step-by-step processing, low efficiency. Usually, one side is first treated with a hydrophilic treatment (such as corona treatment, chemical primer), and after it is completed, the back plate is turned over to treat the other side with a hydrophobic treatment (such as spraying a fluorine / silicon-containing hydrophobic agent). This two-step process has a long process flow, occupies many devices, and has low production efficiency. ② There is chemical reagent pollution. The existing hydrophobic treatment mostly uses the method of spraying liquid fluorine / silicon-containing compounds, which may volatilize during production, causing environmental pollution and occupational health risks, and subsequent curing is required, increasing energy consumption and process complexity. ③ The chemical coating may have problems such as uneven thickness and poor adhesion, and the step-by-step processing may also cause contamination or damage to the treated surface due to secondary operations.

[0005] Based on the above-mentioned defects of the prior art, there is an urgent need for a device and method that can simultaneously, efficiently and environmentally friendly achieve the hydrophilic-hydrophobic double-sided modification of photovoltaic back plates. SUMMARY

[0006] The present application provides a kind of solar photovoltaic back plate hydrophilic-hydrophobic double-sided synchronous processing device and method, by a highly integrated plasma reaction system, in the single transmission process of photovoltaic back plate, two different properties plasma are generated in its two sides space respectively, to realize the hydrophilic modification of back plate inner side and the deposition of hydrophobic coating of outer side, complete the one-step efficient preparation of functional photovoltaic back plate material. The present application solves the technical problems of the prior art that the double-sided processing of photovoltaic back plate needs to be carried out in steps, has low efficiency, and may cause environmental pollution using chemical reagents.

[0007] To achieve the above object, the present application adopts the following technical scheme: The present application provides a kind of solar photovoltaic back plate hydrophilic-hydrophobic double-sided synchronous processing device, including conveying mechanism, hydrophilic treatment module and hydrophobic treatment module;The conveying mechanism is used to convey photovoltaic back plate;The hydrophilic treatment module is distributed in one side of conveying mechanism, for carrying out hydrophilic treatment to one side of photovoltaic back plate;The hydrophobic treatment module is distributed in the other side of conveying mechanism, for carrying out hydrophobic treatment to the other side of photovoltaic back plate.

[0008] Further, the conveying mechanism includes a plurality of conveying modules, the conveying surfaces of the conveying modules are distributed on the same plane, and a gap is provided between adjacent two conveying modules;The hydrophilic treatment module / hydrophobic treatment module carries out hydrophilic / hydrophobic treatment on photovoltaic back plate through the gap; Further, the hydrophilic treatment module is distributed on the side of the photovoltaic backboard away from the conveying mechanism, and comprises a first gas supply assembly and at least one hydrophilic treatment module; the hydrophilic treatment module comprises a first insulating shell and a first electrode; the opening of the first insulating shell faces the surface of the photovoltaic backboard, and the first electrode is arranged inside the first insulating shell; the first insulating shell is provided with an air inlet, and the airflow of the first gas supply assembly can enter the inside of the first insulating shell through the air inlet; after the first electrode is electrified, plasma discharge is generated to form a hydrophilic layer on the surface of the photovoltaic backboard.

[0009] Further, the first gas supply assembly comprises a first gas cylinder and a first conveying pipeline; the first gas cylinder is connected with the first conveying pipeline, the gas outlet end of the first conveying pipeline is connected with the air inlet of the first insulating shell, and a first flow meter is arranged on the first conveying pipeline; the gas in the first gas cylinder is one or a mixture of multiple of air, oxygen and argon.

[0010] Further, the first electrode is in a structure of large at the top and small at the bottom and triangular in cross section, and the material of the first electrode is copper.

[0011] Further, the hydrophobic treatment module is distributed on the side of the photovoltaic backboard facing the conveying mechanism, and comprises a second gas supply assembly, a hydrophobic precursor supply assembly and at least one hydrophobic treatment module; the hydrophobic treatment module comprises a second insulating shell and a second electrode; the opening of the second insulating shell faces the surface of the photovoltaic backboard, and the second electrode is arranged inside the second insulating shell, and the second electrode cover is provided with an insulating barrier medium; the second insulating shell is provided with an inlet, and the gas of the second gas supply assembly and the hydrophobic precursor of the hydrophobic precursor supply assembly can enter the inside of the second insulating shell through the inlet; after the second electrode is electrified, plasma discharge is generated to form a hydrophobic layer on the surface of the photovoltaic backboard.

[0012] Further, the second gas supply assembly comprises a second gas cylinder and a second conveying pipeline, the second gas cylinder is connected with the second conveying pipeline, the gas outlet end of the second conveying pipeline is connected with the inlet of the second insulating shell, and a second flow meter is arranged on the second conveying pipeline; the gas in the second gas cylinder is air, argon or helium; the hydrophobic precursor supply assembly comprises a hydrophobic precursor storage bottle and a third conveying pipeline, the hydrophobic precursor storage bottle is connected with the third conveying pipeline, the third conveying pipeline is connected with the inlet of the second insulating shell, and a third flow meter is arranged on the third conveying pipeline; the hydrophobic precursor storage bottle is provided with a silane compound or a fluorine-containing alkane compound.

[0013] Further, the second electrode is in a cylindrical structure, and the material of the second electrode is copper; the material of the insulating barrier medium is alumina ceramic or quartz glass.

[0014] Further, two transparent insulation cavities are arranged on both sides of the conveying mechanism, and the hydrophilic treatment module and the hydrophobic treatment module are arranged in the two transparent insulation cavities respectively; the transparent insulation cavity arranged on one side of the conveying surface of the conveying mechanism is provided with a first flexible gate and a second flexible gate, one end of the first flexible gate / second flexible gate is movably connected with the opening end of the transparent insulation cavity, and the other end is in contact with the conveying surface of the conveying mechanism.

[0015] Further, a power supply is arranged, and the power supply is connected with the electrodes of the hydrophilic treatment module and the hydrophobic treatment module.

[0016] Further, a support module is arranged, and the support module comprises a base and a plurality of support columns, the support columns are fixed on the base and are used for supporting and fixing the conveying mechanism and the transparent insulation cavities.

[0017] (2) The application further provides a solar photovoltaic backboard hydrophilic-hydrophobic double-sided synchronous processing method, which is realized based on the solar photovoltaic backboard hydrophilic-hydrophobic double-sided synchronous processing device and comprises the following steps: The photovoltaic backboard to be processed is placed on the conveying mechanism, the photovoltaic backboard passes through the processing area at a constant speed through the conveying mechanism, one side of the photovoltaic backboard faces the hydrophilic treatment module, and the other side of the photovoltaic backboard faces the hydrophobic treatment module; when the photovoltaic backboard enters the processing area, the power supply is started, the electrodes of the hydrophilic treatment module and the hydrophobic treatment module are powered on, and corresponding working gas and hydrophobic precursor are respectively introduced; the electrodes of the hydrophilic treatment module are discharged to generate plasma, and a hydrophilic layer is formed on one side surface of the photovoltaic backboard; the electrodes of the hydrophobic treatment module are discharged to generate plasma, and the other side surface of the photovoltaic backboard is subjected to hydrophobic treatment through the gaps between the conveying modules in the conveying mechanism to form a hydrophobic layer; after being subjected to synchronous processing of the hydrophilic treatment module and the hydrophobic treatment module, the photovoltaic backboard leaves through the conveying mechanism and enters the next process.

[0018] Further, the working gas flow rate of the hydrophilic treatment module is 5-10 L / min, the working gas flow rate of the hydrophobic treatment module is 7-15 L / min, the flow rate of the hydrophobic precursor is 0.2-4 L / min, the conveying speed of the conveying mechanism is 1-3 m / min, and the discharge voltage of the power supply is 5-20 kV.

[0019] The application has the following beneficial effects: (1) Compared with the method of processing the two sides of the photovoltaic backboard respectively in the prior art, the plasma surface treatment device can realize synchronous processing of the hydrophilic and hydrophobic sides, the upper and lower surfaces of the photovoltaic backboard can be simultaneously subjected to different plasma treatments in one conveying process through the unique design of the upper and lower electrodes and the cooperation of the hollow conveying belt, and the hydrophilic modification and the hydrophobic modification of the inner and outer sides of the photovoltaic backboard are simultaneously completed; (2) Compared with the traditional surface treatment method which uses a large amount of acid, alkali solution, organic solvent and other chemical reagents, the present application uses plasma for surface treatment, and the whole process only involves air, argon and a small amount of hydrophobic medium containing silicon and fluorine. These substances will not pollute the environment under normal use. The plasma treatment process is a combination of physical and chemical reactions, which will not produce harmful chemical residues. The surface of the treated photovoltaic backboard is clean, and no additional cleaning and other post-processing procedures are required, thus avoiding the generation of waste water from the source; (3) The plasma hydrophilic treatment of the hydrophilic treatment module of the present application is carried out by micro-etching and polar functional group grafting on the surface of the material body, and the formed hydrophilic surface is more stable and durable, without the risk of small molecule organic migration or precipitation, thus ensuring the long-term stability of the surface. The hydrophobic coating generated by the hydrophobic treatment module through plasma polymerization has good compactness, uniformity and chemical bonding effect with the substrate, effectively overcoming the problems of uneven film thickness, weak adhesion and pinhole defects that may exist in traditional spraying or coating processes; (4) The present application can adjust the discharge power, gas type, flow ratio, treatment time and other parameters of the upper and lower electrode modules, and can realize customized processing of the double-sided treatment effect of the photovoltaic backboard, and thus can adapt to the processing needs of photovoltaic backboards of different materials (such as PET, PVDF, etc.) and different specifications. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic diagram of the solar photovoltaic backboard hydrophilic-hydrophobic double-sided synchronous treatment device of the present application; Figure 2 is a schematic diagram of the hydrophilic treatment module and the hydrophobic treatment module of the present application; The marks in the drawings are: 1, photovoltaic backboard; 2, conveying module; 3, first electrode; 4, first insulating shell; 5, second electrode; 6, insulating barrier medium; 7, power supply; 8, transparent insulating cavity; 9, first flexible gate; 10, second flexible gate; 11, support; 12, base; 13, first gas supply assembly; 14, second gas supply assembly; 15, hydrophobic precursor supply assembly; G1, first flow meter; G2, second flow meter; G3, third flow meter; P1, hydrophilic treatment module; P2, hydrophobic treatment module; H1, first interface; H2, second interface. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figures 1-2 As shown, this invention provides a synchronous bifacial treatment device for a solar photovoltaic backsheet, comprising a power supply 7, a conveying mechanism, a hydrophilic treatment module, and a hydrophobic treatment module. The power supply 7 is connected to the electrodes of the hydrophilic and hydrophobic treatment modules via corresponding interfaces, providing power to both modules. The power supply 7 can employ a high-frequency AC power supply, a microsecond pulse power supply, or a nanosecond pulse power supply to achieve precise control of plasma characteristics (such as electron density and temperature). The conveying mechanism is horizontally positioned for conveying the photovoltaic backsheet 1. The hydrophilic treatment module is located above the conveying mechanism and is used to perform hydrophilic treatment on the upper surface of the photovoltaic backsheet 1. The hydrophobic treatment module is located below the conveying mechanism and is used to perform hydrophobic treatment on the lower surface of the photovoltaic backsheet 1.

[0023] The transmission mechanism includes four transmission modules 2, which can be configured as conveyor belts. The lengths of each conveyor belt can be the same or different. The conveyor belts are made of a material with high dielectric constant and low loss. Their excellent dielectric properties ensure the stability and uniformity of the electric field between the upper and lower electrodes, preventing abnormal discharge. The transmission surfaces of each transmission module 2 are distributed on the same plane, with a certain distance between adjacent transmission modules 2. The hydrophobic treatment module can perform hydrophilic / hydrophobic treatment on the photovoltaic backsheet 1 through this hollow gap. This "hollow" design not only enables the carrying and transmission of large-scale photovoltaic backsheets but also provides a "window" for plasma treatment on both the upper and lower sides, facilitating the treatment of the photovoltaic backsheet surface by the lower plasma.

[0024] The hydrophilic treatment modules are distributed above the photovoltaic backsheet 1 and the conveying mechanism. Their function is to generate highly active plasma for hydrophilic modification of the inner surface of the photovoltaic backsheet (the interface with EVA). The modules include a first gas supply component 13 and three hydrophilic treatment modules, which are equidistantly distributed. Each hydrophilic treatment module includes a first insulating shell 4 and a first electrode 3. The opening of the first insulating shell 4 faces the upper surface of the photovoltaic backsheet 1. The first electrode 3 is mounted inside the first insulating shell 4 via a bracket. The first electrode 3 has a triangular cross-section, wider at the top and narrower at the bottom, and is made of copper. The first insulating shell 4 has an air inlet, through which the airflow from the first gas supply component 13 enters the interior of the first insulating shell 4. The first insulating shell 4 uniformly guides the gas between the first electrode 3 and the upper surface of the photovoltaic backsheet 1. The power supply 7 applies voltage to the first electrode 3 through the first interface H1, thereby activating the gas, completing plasma discharge and treating the upper surface of the photovoltaic backsheet 1, forming a hydrophilic layer on the surface of the photovoltaic backsheet 1. Three hydrophilic treatment modules are arranged in an array, which enables efficient hydrophilic treatment of large-scale backsheet materials.

[0025] like Figure 1 As shown, the first gas supply assembly 13 includes a first gas cylinder and a first delivery pipe. The first gas cylinder is connected to the first delivery pipe, and the outlet of the first delivery pipe is connected to the inlet of one or more first insulating shells 4. A first flow meter G1 is installed on the first delivery pipe to control the gas flow rate and the amount added. The gas in the first gas cylinder is one or more mixtures of air, oxygen, and argon.

[0026] The hydrophobic treatment module is located below the photovoltaic backsheet 1 and the conveying mechanism, forming a treatment area in conjunction with the hydrophilic treatment module. Its core function is to construct a hydrophobic coating on the outer surface of the photovoltaic backsheet 1 (the surface exposed to the environment in the future) using plasma polymerization technology. The hydrophobic treatment module includes a second gas supply component 14, a hydrophobic precursor supply component 15, and three hydrophobic treatment modules. The three hydrophobic treatment modules are equidistantly distributed, corresponding to the space gaps between the conveying modules 2. Each hydrophobic treatment module includes a second insulating shell and a second electrode 5. The opening of the second insulating shell faces the lower surface of the photovoltaic backsheet 1. The second electrode 5 is mounted inside the second insulating shell by a bracket. The second electrode 5 has a cylindrical structure and is made of copper. The second electrode 5 is covered with an insulating barrier medium 6, which is made of alumina ceramic or quartz glass. It covers the surface of the second electrode 5 to protect it and stabilize the discharge. The second insulating shell is equipped with an inlet. The gas from the second gas supply component 14 and the hydrophobic precursor from the hydrophobic precursor supply component 15 can be mixed and then enter the interior of the second insulating shell through the inlet. The power supply 7 applies voltage to the second electrode 5 through the second interface H2, generating plasma discharge on the lower surface of the photovoltaic backsheet 1. Hydrophobic treatment is performed on the lower surface of the photovoltaic backsheet 1 through the space gap between the transmission modules 2, forming a hydrophobic layer on the surface of the photovoltaic backsheet 1. The three hydrophobic treatment modules are arranged in an array, which can achieve efficient hydrophobic treatment of large-scale backsheet materials.

[0027] like Figure 1 As shown, the second gas supply assembly 14 includes a second gas cylinder and a second delivery pipe. The second gas cylinder is connected to the second delivery pipe, and the outlet of the second delivery pipe is connected to the inlet of the mixing pipe. A second flow meter for controlling the flow rate is installed on the second delivery pipe. The gas in the second gas cylinder is air, argon, or helium. The hydrophobic precursor supply assembly 15 includes a hydrophobic precursor storage bottle and a third delivery pipe. The hydrophobic precursor storage bottle is connected to the third delivery pipe, and the third delivery pipe is connected to the inlet of the mixing pipe. A third flow meter for controlling the flow rate is installed on the third delivery pipe. The hydrophobic precursor storage bottle contains a silane-containing compound or a fluoroalkane-containing compound. The hydrophobic precursor enters the mixing pipe in gaseous form through the third delivery pipe. The outlet of the mixing pipe is connected to one or more inlets of a second insulating shell. The gas in the second gas cylinder mixes with the hydrophobic precursor in the mixing pipe and then enters the interior of the second insulating shell.

[0028] The first electrode 3 adopts an inverted triangular structure with a larger top and smaller bottom, designed to optimize the electric field distribution and induce corona discharge. The electric field is concentrated at the apex of the triangle, facilitating the generation of a high-intensity local electric field, which is beneficial for corona discharge. Corona discharge effectively performs physical etching and chemical grafting on the surface of the photovoltaic backsheet 1, introducing polar functional groups such as hydroxyl and carboxyl groups, thereby achieving hydrophilic modification. The second electrode 5 adopts a cylindrical structure, facilitating the uniform outer edge blocking dielectric 6, thus forming a dielectric barrier discharge (DBD) structure. The cylindrical structure of the second electrode 5 promotes a uniform electric field distribution, forming a stable dielectric barrier discharge. Furthermore, the insulating dielectric layer prevents the electrode from direct contact with the plasma, avoiding abnormal discharge and maintaining discharge stability. This structure facilitates the fragmentation and activation of hydrophobic precursors in the plasma, resulting in the uniform deposition of a hydrophobic thin film on the surface of the photovoltaic backsheet 1.

[0029] As a further preferred embodiment of the present invention, two transparent insulating cavities 8 (made of plexiglass) are provided, one above and one below the conveying mechanism. A hydrophilic treatment module is disposed within the transparent insulating cavity 8 above the conveying mechanism, and a hydrophobic treatment module is disposed within the transparent insulating cavity 8 below the conveying mechanism. The top surface of the transparent insulating cavity 8 located below the conveying mechanism is open, and its open end is connected to the bottom of the conveying mechanism. The bottom surface of the transparent insulating cavity 8 located above the conveying mechanism is open, and the two side walls of the open end of the transparent insulating cavity 8 are respectively provided with a first flexible gate 9 and a second flexible gate 10 in the shape of a triangular pyramid. One end of the first flexible gate 9 / second flexible gate 10 is movably connected to the open end of the transparent insulating cavity 8 (through a rotating shaft and a torsion spring), and the other end is in contact with the conveying surface of the conveying mechanism, ensuring that the photovoltaic backsheet 1 is sent into the plasma discharge space while the plasma working gas does not leak in large quantities.

[0030] As a further preferred embodiment of the present invention, a support module is also provided. The support module includes a base 12 and several pillars 11. The pillars 11 are fixed on the base 12 and are used to support and fix the conveying mechanism and the transparent insulating cavity 8, providing solid mechanical support and stability for the entire device, ensuring the smooth operation of the conveyor belt, and also ensuring the long-term accurate alignment of the relative positions between the upper and lower electrodes.

[0031] The specific operating steps for using the above-mentioned hydrophilic-hydrophobic dual-sided synchronous treatment device for solar photovoltaic backsheets are as follows: The photovoltaic backsheet 1 to be processed is placed on the conveying mechanism with its inner side facing up and its outer side facing down. The conveying mechanism carries the photovoltaic backsheet 1 through the processing area composed of upper and lower electrode matrices at a constant speed, with the upper surface of the photovoltaic backsheet 1 facing the hydrophilic processing module and the lower surface facing the hydrophobic processing module.

[0032] The moment the photovoltaic backsheet 1 enters the processing area, the power supply 7 is activated, and the power supply 7 simultaneously applies precisely controlled power to the electrodes of the hydrophilic and hydrophobic processing modules.

[0033] Simultaneously, the hydrophilic treatment module is activated, and a working gas (air, oxygen, argon, or a mixture thereof) is introduced. The first electrode 3 generates plasma rich in various active particles, such as oxygen free radicals (O•) and excited-state oxygen molecules, through corona discharge, which bombards the upper surface (inner side) of the photovoltaic backsheet 1. The high-energy particles and active oxygen species in the plasma physically etch the surface of materials such as PET / PVDF to increase their micro-roughness, and simultaneously graft strongly polar functional groups such as hydroxyl (-OH) and carboxyl (-COOH) groups onto the polymer molecular chains through chemical reactions, thereby significantly increasing the surface energy and achieving hydrophilic modification.

[0034] The hydrophobic treatment module is activated simultaneously, introducing a working gas (air, argon, or helium) and a hydrophobic precursor (such as hexamethyldisiloxane HMDSO or perfluorohexane C6F14). Plasma is formed through a dielectric barrier discharge electrode consisting of the second electrode 5 and an insulating barrier medium 6. The hydrophobic precursor molecules are broken down by high-energy electron collisions, generating silicon- or fluorine-containing active free radicals. These active groups are subsequently adsorbed, migrated, and undergo cross-linking polymerization on the lower surface of the photovoltaic backsheet 1, ultimately forming a thin, chemically bonded siloxane or fluorocarbon polymer film. This film, with its extremely low surface energy, imparts hydrophobicity to the outer surface of the photovoltaic backsheet 1.

[0035] After being processed simultaneously by the hydrophilic and hydrophobic treatment modules, the photovoltaic backsheet 1 has completed its double-sided differentiated high-performance modification in the output processing area and can directly enter the next packaging process, thereby realizing the simultaneous hydrophilic-hydrophobic double-sided treatment of large-scale photovoltaic backsheets.

[0036] The selectable range of specific plasma operating parameters is as follows: When the first electrode 3 is modified for hydrophilicity, the working gas flow rate can be selected as 5~10L / min. Such parameter settings can effectively introduce hydrophilic groups into the surface of PET material and improve hydrophilicity.

[0037] When the second electrode 5 undergoes hydrophobic modification, the flow rate of the reaction medium (hydrophobic precursor) is controlled at 0.2~4 L / min, and the flow rate of the working gas is controlled at 7~15 L / min. Under these parameters, a hydrophobic layer is formed on the lower surface of the PET material, effectively improving the water contact angle. The discharge voltage of the power supply 7 can be set to 5~20 kV, and the conveyor belt speed is 1~3 m / min.

[0038] Example 1 The PET photovoltaic backsheet 1 to be processed is placed on the string-type transmission module 2, with its upper surface (the inner surface that will be combined with EVA in the future) facing upward and its lower surface (the outer surface that will be exposed to the environment in the future) facing downward.

[0039] The speed of the conveying module 2 is precisely controlled by a servo motor, which delivers the photovoltaic backsheet 1 between the hydrophilic treatment module P1 and the hydrophobic treatment module P2 at a speed of 1 meter / min.

[0040] The hydrophilic treatment module P1 uses air as the working gas with a gas flow rate of 6.5 L / min. Its triangular first electrode 3 is made of copper and its surface is precision polished to optimize the electric field distribution.

[0041] The hydrophobic treatment module P2 uses argon as the working gas at a flow rate of 7.5 L / min, and hexamethyldisiloxane as the hydrophobic precursor, which is mixed with the working gas at a flow rate of 2.5 L / min. The cylindrical second electrode 5 is made of metallic copper, and its outer side is wrapped with a layer of high-purity, high-density alumina ceramic insulating barrier dielectric 6 to form a dielectric barrier discharge.

[0042] To ensure the controllability of the reaction process and maintain the local environment of the processing area, upper and lower transparent insulating cavities 8 made of high-transparency quartz glass are set around the reaction area, together forming a semi-enclosed reaction gas chamber. The upper transparent insulating cavity 8 and the moving conveyor module 2 are dynamically sealed through a first flexible gate 9 and a second flexible gate 10 in the shape of a triangular pyramid. This sealing structure can effectively limit the exchange of internal gas with the external atmosphere, while allowing the conveyor belt to pass smoothly.

[0043] In the discharge region of the hydrophilic treatment module P1, dry air is ionized to generate hydrophilic plasma rich in oxygen free radicals and ozone. The high-energy particles and active species in the plasma cause micro-etching on the upper surface of the photovoltaic backsheet 1 and introduce a large number of polar oxygen-containing functional groups, thereby completing surface activation and forming a hydrophilic layer.

[0044] In the discharge region of the hydrophobic treatment module P2, argon gas is first ionized as a carrier gas to form plasma, providing an energy environment for the cracking of HMDSO (hexamethyldisiloxane) molecules. HMDSO molecules dissociate into free radicals containing Si, O, and CHx in the plasma. These active groups are deposited on the lower surface of the photovoltaic backsheet 1 to form a low-polarity siloxane film.

[0045] After treatment, the photovoltaic backsheet 1 achieved the expected hydrophilic and hydrophobic effects on both sides in one step. Testing of the PET photovoltaic backsheet treated by the method of this invention showed that the water contact angle on its upper surface decreased from 78° before treatment to below 35°, exhibiting excellent hydrophilicity; while the water contact angle on its lower surface increased to above 113°, exhibiting outstanding hydrophobicity.

[0046] The above results fully demonstrate that the present invention has successfully achieved high-performance differentiated functional modification of both sides of photovoltaic backsheets in a single continuous process in an efficient and environmentally friendly manner.

[0047] This invention integrates the two separate processes of hydrophilic and hydrophobic treatment, which must be performed in stages in traditional processes, through an original structural design of upper and lower electrode modules and a hollow conveyor belt. These processes can be completed simultaneously, eliminating the need for inter-process transfer, waiting, and repeated positioning and clamping, thus significantly shortening the processing cycle and increasing production capacity per unit time. Furthermore, the entire process is a dry physical process, eliminating the need for liquid chemical reagents such as acid and alkali solutions and organic solvents used in traditional wet chemical methods. This not only avoids pollution of the working environment and atmosphere caused by volatile organic compound emissions but also eliminates the need for subsequent complex chemical waste treatment, providing key technological support for the sustainable development of the photovoltaic industry chain.

[0048] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A device for simultaneous hydrophilic and hydrophobic dual-sided treatment of solar photovoltaic backsheets, characterized in that, Includes a conveying mechanism, a hydrophilic treatment module, and a hydrophobic treatment module; The conveying mechanism is used to convey the photovoltaic backsheet (1); the hydrophilic treatment module is distributed on one side of the conveying mechanism and is used to perform hydrophilic treatment on one side of the photovoltaic backsheet (1); the hydrophobic treatment module is distributed on the other side of the conveying mechanism and is used to perform hydrophobic treatment on the other side of the photovoltaic backsheet (1).

2. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 1, characterized in that, The transmission mechanism includes several transmission modules (2), and the transmission surfaces of each transmission module (2) are distributed on the same plane. There is a gap between two adjacent transmission modules (2). The hydrophilic treatment module / hydrophobic treatment module performs hydrophilic / hydrophobic treatment on the photovoltaic backsheet (1) through the gap.

3. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 1, characterized in that, The hydrophilic treatment module is distributed on the side of the photovoltaic backsheet (1) facing away from the conveying mechanism, and includes a first gas supply component (13) and at least one hydrophilic treatment module. The hydrophilic treatment module includes a first insulating shell (4) and a first electrode (3); the opening of the first insulating shell (4) faces the surface of the photovoltaic backsheet (1), and the first electrode (3) is disposed inside the first insulating shell (4); the first insulating shell (4) is provided with an air inlet, and the airflow of the first air supply component (13) can enter the interior of the first insulating shell (4) through the air inlet. After the first electrode (3) is energized, it generates plasma discharge and forms a hydrophilic layer on the surface of the photovoltaic backsheet (1).

4. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 3, characterized in that, The first gas supply assembly (13) includes a first gas cylinder and a first delivery pipeline; The first gas cylinder is connected to the first conveying pipe, the outlet of the first conveying pipe is connected to the inlet of the first insulating shell (4), and a first flow meter is provided on the first conveying pipe; The gas in the first gas cylinder is one or more of air, oxygen, and argon.

5. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 3, characterized in that, The first electrode (3) has a structure that is larger at the top and smaller at the bottom and has a triangular cross-section. The material of the first electrode (3) is copper.

6. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 1, characterized in that, The hydrophobic treatment module is distributed on the side of the photovoltaic backsheet (1) facing the conveying mechanism, and includes a second gas supply component (14), a hydrophobic precursor supply component (15) and at least one hydrophobic treatment module. The hydrophobic treatment module includes a second insulating shell and a second electrode (5); the opening of the second insulating shell faces the surface of the photovoltaic backsheet (1), the second electrode (5) is disposed inside the second insulating shell, and the second electrode (5) is covered with an insulating barrier medium (6). The second insulating shell is provided with an inlet, and the gas of the second gas supply component (14) and the hydrophobic precursor of the hydrophobic precursor supply component (15) can enter the interior of the second insulating shell through the inlet. After the second electrode (5) is energized, plasma discharge is generated, and a hydrophobic layer is formed on the surface of the photovoltaic backsheet (1).

7. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 6, characterized in that, The second gas supply assembly (14) includes a second gas cylinder and a second delivery pipe. The second gas cylinder is connected to the second delivery pipe. The outlet of the second delivery pipe is connected to the inlet of the second insulating shell. A second flow meter is installed on the second delivery pipe. The gas in the second gas cylinder is air, argon, or helium. The hydrophobic precursor supply assembly (15) includes a hydrophobic precursor storage bottle and a third delivery pipe. The hydrophobic precursor storage bottle is connected to the third delivery pipe, and the third delivery pipe is connected to the inlet of the second insulating shell. A third flow meter is installed on the third delivery pipe. The hydrophobic precursor storage bottle contains silane compounds or fluoroalkane compounds.

8. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 6, characterized in that, The second electrode (5) has a cylindrical structure and is made of copper; The insulating barrier medium (6) is made of alumina ceramic or quartz glass.

9. The solar photovoltaic backsheet hydrophilic-hydrophobic dual-sided synchronous treatment device according to claim 1, characterized in that, Two transparent insulating cavities (8) are also provided, which are respectively located on both sides of the conveying mechanism; The hydrophilic treatment module and the hydrophobic treatment module are respectively installed inside two transparent insulating cavities (8); The transparent insulating cavity (8) distributed on one side of the conveying surface of the conveying mechanism is provided with a first flexible gate (9) and a second flexible gate (10). One end of the first flexible gate (9) / second flexible gate (10) is movably connected to the opening end of the transparent insulating cavity (8), and the other end is in contact with the conveying surface of the conveying mechanism.

10. A method for simultaneous hydrophilic-hydrophobic dual-sided treatment of a solar photovoltaic backsheet, implemented based on the simultaneous hydrophilic-hydrophobic dual-sided treatment device for a solar photovoltaic backsheet as described in any one of claims 1 to 9, characterized in that, include: The photovoltaic backsheet to be processed is placed on the conveying mechanism. The photovoltaic backsheet passes through the processing area at a constant speed through the conveying mechanism. One side of the photovoltaic backsheet faces the hydrophilic processing module, and the other side faces the hydrophobic processing module. When the photovoltaic backsheet enters the processing area, the power is turned on and the electrodes of the hydrophilic treatment module and the hydrophobic treatment module are powered on, respectively introducing the corresponding working gas and hydrophobic precursor; the electrodes of the hydrophilic treatment module discharge to generate plasma, forming a hydrophilic layer on one side of the photovoltaic backsheet; the electrodes of the hydrophobic treatment module discharge to generate plasma, which, through the gaps between the various transmission modules (2) in the transmission mechanism, performs hydrophobic treatment on the other side of the photovoltaic backsheet to form a hydrophobic layer.

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