Packaging adhesive film and application thereof

Abstract

The invention provides a packaging adhesive film and application thereof. The packaging adhesive film comprises a light conversion layer, the light conversion layer comprises first matrix resin and a first light conversion agent, and the light conversion layer does not contain a cross-linking agent; the first light conversion agent is a first organic fluorescent compound containing a first polar group. A system without a cross-linking agent is used in a light conversion layer of the packaging adhesive film, and an organic fluorescent compound terminated by a polar group is selected as a light conversion agent, so that the light conversion agent is effectively prevented from being separated out and migrated, the light conversion efficiency and stability of the packaging adhesive film are improved, and the service life of the packaging adhesive film is prolonged. Therefore, the power generation efficiency and long-term reliability of the solar cell module in an ultraviolet environment are facilitated, the production process is simplified, the manufacturing cost is reduced, and the development of an N-type cell technology, especially an HJT and TOPCon cell module packaging technology is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaics, and more particularly, to an encapsulation film and its application. Background Art

[0002] In the production process of solar cells, a photovoltaic encapsulation film is a key material. Its main function is to bond solar cell wafers together with other components such as glass and backsheets to form an integral whole, providing physical protection for the solar cell wafers, isolating the adverse effects of the external environment, and significantly extending the service life of solar cells. However, during the use of solar cells, especially heterojunction (HJT) cell wafers, due to their long-term exposure to sunlight, ultraviolet light causes greater damage to the cell wafers, affecting the power generation efficiency of solar cells.

[0003] In view of the ultraviolet sensitivity of HJT cell wafers and the higher requirements for ultraviolet protection in the context of the efficiency improvement of TOPCon cells, researchers have started to add light conversion agents to photovoltaic encapsulation films, aiming to convert ultraviolet light into visible light. This conversion process is achieved by the light conversion agent absorbing ultraviolet photons, jumping to the excited state, and then de-exciting and emitting blue or red light, which can improve the light transmittance performance of the encapsulation film and indirectly promote the improvement of the power generation efficiency of solar cells.

[0004] However, light conversion agents are usually organic materials, and their compatibility with the main component of the encapsulation film, polyolefin resin, is poor. This shortcoming is manifested during use as the migration of the light conversion agent to the surface of the film, resulting in a gradual decrease in the light conversion efficiency. In addition, due to uneven distribution during the processing, the light conversion agent is prone to agglomeration under humid and hot conditions, and even migrates to the back of the component in a high-temperature environment, not only affecting the appearance of the film but also directly damaging its light conversion performance.

[0005] Therefore, there is an urgent need to develop a new type of encapsulation film that can effectively prevent the migration of the light conversion agent while maintaining the optical properties and mechanical stability of the encapsulation film, ensuring the long-term stable operation of solar cell components in an ultraviolet environment and maximizing the power generation efficiency and service life. Summary of the Invention

[0006] The main object of the present invention is to provide an encapsulation material and its application to solve the problem in the prior art that the light conversion agent is prone to precipitate and migrate from the encapsulation film, resulting in poor light conversion efficiency of the film.

[0007] To achieve the above object, according to one aspect of the present invention, there is provided an encapsulation film including a light conversion layer, the light conversion layer including a first matrix resin and a first light conversion agent, and the light conversion layer not containing a crosslinking agent; the first light conversion agent is a first organic fluorescent compound containing a first polar group.

[0008] Further, the first polar group includes one or more of maleic anhydride group, triallyl isocyanurate group, acrylic acid-containing group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group and glycidyl group; preferably amide group and / or glycidyl group.

[0009] Further, the acrylic acid-containing group includes acrylic acid and / or methacrylic acid group; and / or, the ester group includes acrylate group; preferably, the acrylate group includes one or more of alkyl acrylate group, alkyl methacrylate group, phenyl acrylate group, phenyl methacrylate group, benzyl acrylate group, trimethylolpropane triacrylate group, pentaerythritol triacrylate group and ethoxylated trimethylolpropane triacrylate group; more preferably, the alkyl acrylate group includes one or more of methyl acrylate group, ethyl acrylate group, butyl acrylate group, cyclohexyl acrylate group and 2-ethylhexyl acrylate group; more preferably, the alkyl methacrylate group includes one or more of methyl methacrylate group, ethyl methacrylate group, butyl methacrylate group, cyclohexyl methacrylate group and 2-ethylhexyl methacrylate group; and / or, the amide group includes one or more of acrylamide group, methacrylamide group, N-methylmethacrylamide group, N-ethylmethacrylamide group, N-isopropylmethacrylamide group, N-tert-butylmethacrylamide group, N-hydroxymethylmethacrylamide group, N-hydroxyethylmethacrylamide group, N-(2-hydroxypropyl)methacrylamide group, N,N'-methylenebisacrylamide group, maleimide group, oleic acid amide group, 9-hexadecenamide group, N-(2-hydroxyethyl)-undec-10-enamide group, 9-tetradecenamide group, 9-dodecenamide group, 9-decenamide group, octenamide group, heptenamide group, hexenamide group, pentenamide group and butenamide group.

[0010] Further, the weight percentage content of the first polar group in the first light conversion agent is 0.1-15%.

[0011] Further, the functional groups of the first organic fluorescent compound include one or more of benzotriazolyl, triazinyl, benzophenone group, carbazolyl, quinoxalinyl, benzimidazolyl, and triphenylamino group; and / or, the weight average molecular weight of the first light conversion agent is 200 to 5000 g / mol, preferably 1000 to 5000 g / mol; and / or, the first organic fluorescent compound includes an organic small molecule light conversion agent and an organic polymer light conversion agent; preferably, the organic small molecule light conversion agent includes one or more of benzotriazole and its derivatives, triazine and its derivatives, benzophenone and its derivatives, carbazole and its derivatives, quinoxaline and its derivatives, benzimidazole and its derivatives, and triphenylamine and its derivatives; preferably, the copolymerization monomers of the organic polymer light conversion agent contain functional groups and polymerizable groups, the functional groups include one or more of triazolyl, triazinyl, benzophenone group, carbazolyl, quinoxalinyl, benzimidazolyl, and triphenylamino group, and the polymerizable groups include one or more of alkenyl, ester group, hydroxyl group, and carboxyl group; and / or, the weight percentage content of the first light conversion agent in the light conversion layer is 0.01 to 2%.

[0012] Further, the light conversion layer further includes a modified matrix resin, and the modified matrix resin is a second matrix resin graft-modified with a second light conversion agent. Preferably, the grafting rate of the second light conversion agent on the second matrix resin is 0.1 to 10%; preferably, the second light conversion agent is a second organic fluorescent compound containing a second polar group; more preferably, the second polar group includes one or more of maleic anhydride group, triallyl isocyanurate group, acrylic acid-containing group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group, and glycidyl group; more preferably, the functional groups of the second organic fluorescent compound include one or more of benzotriazolyl, triazinyl, benzophenone group, carbazolyl, quinoxalinyl, benzimidazolyl, and triphenylamino group; preferably, by weight percentage, the light conversion layer includes 10 to 93% of the first matrix resin, 5 to 89% of the modified matrix resin, and 0.01 to 2% of the first light conversion agent.

[0013] Further, the first matrix resin and the second matrix resin independently include vinyl polymers; preferably, the vinyl polymer is one or more of ethylene-vinyl acetate, polyethylene, hyperbranched polyethylene, and ethylene-α-olefin copolymer; more preferably, the density of polyethylene is 0.91 to 0.93 g / cm 3 ; more preferably, the degree of branching of hyperbranched polyethylene is 40 to 140 branches / 1000 carbons; more preferably, the ethylene-α-olefin copolymer includes one or more of ethylene-butene copolymer, ethylene-octene copolymer, ethylene-hexene copolymer, and ethylene-propylene-hexene copolymer; preferably, the melting point of the vinyl polymer is 86 to 125 °C, more preferably 90 to 120 °C, and further preferably 90 to 115 °C;

[0014] Preferably, the first matrix resin and the second matrix resin also independently include one or more of ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethyl-methyl acrylate copolymer, ethylene-butyl acrylate copolymer, polyvinyl butyral, low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, polypropylene, ionomer and silicone.

[0015] Furthermore, the thickness of the light conversion layer is 50-500 μm; and / or, the encapsulation film further includes an infrared high reflection layer located on at least one side of the light conversion layer, and the infrared high reflection layer includes a third matrix resin and an infrared high reflection filler, and the infrared high reflection filler includes one or more of indium tin oxide, antimony tin oxide, cadmium selenide and cadmium telluride; and / or, the thickness of the infrared high reflection layer is 50-250 μm.

[0016] Furthermore, the encapsulation film further includes an ultraviolet cut-off layer located on at least one side of the light conversion layer; and / or, the thickness of the ultraviolet cut-off layer is 50-250 μm; preferably, the encapsulation film further includes a barrier layer located between the light conversion layer and the ultraviolet cut-off layer, and the barrier layer includes one or more of POE, PP, PE and PET; and / or, the thickness of the barrier layer is 50-250 μm; and / or, the number of layers of the encapsulation film is 2-5 layers.

[0017] Furthermore, the average ultraviolet transmittance of the encapsulation film at 290-380 nm is ≤2%, and the light transmittance at 400-700 nm is ≤91%.

[0018] According to another aspect of the present invention, there is provided an encapsulation device including electronic components, and at least one surface of the electronic components is in contact with the above-mentioned encapsulation film; preferably, the electronic components include one or more of a solar cell, a liquid crystal panel, a field emission device, a plasma display device and a touch screen.

[0019] According to another aspect of the present invention, there is provided a solar cell module including a solar cell, and at least one surface of the solar cell is in contact with the above-mentioned encapsulation film; preferably, a metal wire is attached to one side of the solar cell in contact with the encapsulation film.

[0020] Applying the technical solution of the present invention, by using a crosslinking agent-free system in the light conversion layer of the encapsulation film and selecting an organic fluorescent compound capped with a polar group as the light conversion agent, the precipitation and migration of the light conversion agent are effectively avoided, thereby improving the light conversion efficiency and stability of the encapsulation film. Furthermore, it is beneficial to the power generation efficiency and long-term reliability of the solar cell module in an ultraviolet environment. Moreover, the production process is simplified, the manufacturing cost is reduced, which is conducive to the development of N-type battery technology, especially the encapsulation technology of HJT and TOPCon battery modules. Detailed Embodiments

[0021] It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the embodiments.

[0022] It should be noted that the "first", "second", etc. in the description and claims of the present invention are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances to describe the embodiments of the present invention.

[0023] As described in the background art of the present invention, in the prior art, there is a problem that the light conversion agent is likely to precipitate and migrate from the encapsulation film, resulting in poor light conversion efficiency of the film. To solve the above problems, in a typical embodiment of the present invention, an encapsulation film is provided, which includes a light conversion layer. The light conversion layer includes a first matrix resin and a first light conversion agent, and the light conversion layer does not contain a crosslinking agent; the first light conversion agent is a first organic fluorescent compound containing a first polar group.

[0024] In the prior art, crosslinking agents in encapsulation films are usually used to improve the heat resistance and mechanical strength of the matrix material, and enhance the performance of the encapsulation film by forming a three-dimensional network structure. The inventors unexpectedly found during the experiment that in the light conversion layer, the presence of the crosslinking agent will affect the distribution and activity of the light conversion agent, resulting in a decrease in the light conversion efficiency. For the purpose of avoiding the interaction force between the crosslinking agent and the light conversion agent, the present application specifically designs that the light conversion layer of the encapsulation film does not contain a crosslinking agent. Under this condition, the following beneficial effects are achieved: First, it can avoid the encapsulation or binding of the crosslinking agent to the light conversion agent, enabling the light conversion agent to freely absorb and convert ultraviolet light, thereby improving the light conversion efficiency; Second, in the light conversion layer without a crosslinking agent, the migration and aggregation of the light conversion agent are reduced, and the stability and long-term durability of the light conversion effect are improved, so that the performance of the solar cell module does not decay in an ultraviolet environment; Third, the step of adding a crosslinking agent can be omitted, reducing the production cost and complexity, and improving the production efficiency and consistency of the encapsulation film.

[0025] In addition, the first light conversion agent in the present application is a first organic fluorescent compound capped with a first polar group. As a light conversion agent, the organic fluorescent compound capped with a polar group has the following beneficial effects. First, the polar group and the first matrix resin have a strong interaction (such as polar matching), which can improve the compatibility between the light conversion agent and the matrix, reduce migration and surface precipitation inside the encapsulation film, and thus is conducive to enhancing the overall stability of the light conversion layer. Second, the uniformly distributed light conversion agent has high reactivity, can effectively absorb ultraviolet light and convert it into visible light, has a good light conversion effect, and is conducive to improving the light transmittance of the encapsulation film. Third, the organic fluorescent compound capped with a polar group can resist photoaging to a certain extent, extend the service life of the light conversion layer, and thus is conducive to improving the long-term reliability of the solar cell module. Fourth, compared with the traditional light conversion agent, the light conversion agent capped with a polar group is easy to control during the processing process, has a simpler manufacturing process, and lower production costs.

[0026] It should be noted that the light conversion layer of the encapsulation film in the present application does not contain a crosslinking agent. The crosslinking reaction of the crosslinking agent may form a microscopic network structure, resulting in light scattering. The light conversion layer material without a crosslinking agent is more uniform and has a higher light transmittance, thus improving the utilization rate of light. The dispersibility of the light conversion material (such as phosphor or quantum dot) is better, avoiding the influence of the crosslinked structure on the light path, and ensuring the efficient conversion of ultraviolet light into visible light. And the crosslinking agent may have side reactions (such as yellowing, degradation) with the light conversion material or water and oxygen in the environment. Without a crosslinking agent, such problems can be avoided, and the service life of the module can be extended. However, due to the use of an organic fluorescent compound capped with a polar group as the light conversion agent, on the one hand, it can avoid the encapsulation or binding of the crosslinking agent to the light conversion agent, enabling the light conversion agent to freely absorb and convert ultraviolet light, thereby improving the light conversion efficiency; on the other hand, the organic fluorescent compound capped with a polar group as the light conversion agent can effectively avoid the precipitation and migration of the light conversion agent, which is conducive to improving the light conversion and the stability of the light conversion agent of the encapsulation film, thus achieving a better performance compared with the light conversion layer containing a crosslinking agent.

[0027] In summary, by using a system without a crosslinking agent in the light conversion layer of the encapsulation film and using an organic fluorescent compound capped with a polar group as the light conversion agent, the precipitation and migration of the light conversion agent can be effectively avoided, which is conducive to improving the light conversion efficiency and stability of the encapsulation film, and further conducive to the power generation efficiency and long-term reliability of the solar cell module in an ultraviolet environment. Moreover, it can simplify the production process, reduce the manufacturing cost, and is conducive to the development of N-type battery technologies, especially the encapsulation technologies of HJT and TOPCon battery modules.

[0028] After a lot of experimental research, the inventors have optimized the types of polar groups. In a preferred embodiment, the first polar group includes one or more of maleic anhydride group, triallyl isocyanurate group, acrylic acid-containing group, hydroxyl group, ester group, carbonyl group, amide group, pyridine group, epoxy group, pyrrolidone group and glycidyl group; preferably amide group and / or glycidyl group.

[0029] The above-mentioned polar group-terminated light conversion agent can be grafted and copolymerized with the first matrix resin to form a stable chemical bond, which is not only more conducive to enhancing the combination of the light conversion agent and the matrix resin, but also increases the steric hindrance between the light conversion agent molecules. Larger steric hindrance is more conducive to reducing the free movement of the light conversion agent molecules and preventing surface precipitation under long-term use and complex environmental conditions, thereby further improving the optical properties and light conversion efficiency of the light conversion layer, so that it can remain stable even under harsh conditions. In addition, the formation of chemical bonds can further increase the reactivity of the light conversion agent, making the light conversion process more efficient and further improving the light transmittance of the encapsulation film.

[0030] Based on similar reasons, the inventors further preferred the type of polar groups. In a preferred embodiment, the acrylic acid-containing group includes acrylic acid and / or methacrylic acid. The above-mentioned types of acrylic acid-containing groups can further enhance the physical properties and durability of the composite material, while also ensuring the stable output of the light conversion efficiency.

[0031] In a preferred embodiment, the ester group includes an acrylate group; preferably, the acrylate group includes one or more of an alkyl acrylate group, an alkyl methacrylate group, a phenyl acrylate group, a phenyl methacrylate group, a benzyl acrylate group, a trimethylolpropane triacrylate group, a pentaerythritol triacrylate group, and an ethoxylated trimethylolpropane triacrylate group; more preferably, the alkyl acrylate group includes one or more of a methyl acrylate group, an ethyl acrylate group, a butyl acrylate group, a cyclohexyl acrylate group, and a 2-ethylhexyl acrylate group; more preferably, the alkyl methacrylate group includes one or more of a methyl methacrylate group, an ethyl methacrylate group, a butyl methacrylate group, a cyclohexyl methacrylate group, and a 2-ethylhexyl methacrylate group. The addition of the above-mentioned types of ester groups can further improve the compatibility and stability between the light conversion agent and the base resin.

[0032] In a preferred embodiment, the amide group includes one or more of acrylamide group, methacrylamide group, N-methylacrylamide group, N-ethylacrylamide group, N-isopropylacrylamide group, N-tert-butylacrylamide group, N-hydroxymethylacrylamide group, N-hydroxyethylacrylamide group, N-(2-hydroxypropyl)acrylamide group, N,N'-methylenebisacrylamide group, maleimide group, oleic acid amide group, 9-hexadecenamide group, N-(2-hydroxyethyl)-undec-10-enamide group, 9-tetradecenamide group, 9-dodecenamide group, 9-decenamide group, octenamide group, heptenamide group, hexenamide group, pentenamide group and butenamide group. The addition of the above types of amide groups can not only further enhance the stability and durability of the light conversion agent, but also more significantly improve the light conversion effect of the encapsulation material through its strong interaction with the resin. Especially maleimide group, oleic acid amide group, etc., their chemical properties can further optimize the Stokes shift process and improve the efficiency of ultraviolet to visible light conversion.

[0033] In order to further enhance the intermolecular force between the light conversion agent and the matrix resin, in a preferred embodiment, the weight percentage content of the first polar group in the first light conversion agent is 0.1-15%. Within the above range, it is more conducive to promoting the uniform dispersion of the light conversion agent in the encapsulation material, reducing agglomeration, optimizing the light conversion efficiency of the light conversion agent, and enhancing its chemical stability. However, if the content of the polar group is too high, it may cause a decrease in the physical properties of the encapsulation material, such as reducing transparency, affecting mechanical strength, increasing production costs at the same time, and may affect the activity of the light conversion agent due to excessive steric hindrance. If its content is too low, the amount of the polar group is insufficient, which may lead to weak binding force between the light conversion agent and the matrix resin, affecting the dispersion uniformity and stability, and thus affecting the light conversion efficiency. It should be noted that the test of the weight percentage content of the polar group in the light conversion agent needs to select a suitable method according to the group type and compound properties. The following are common test methods: acid-base titration (applicable to dissociable groups), infrared spectroscopy (FT-IR), ion chromatography (IC), high performance liquid chromatography (HPLC), CHNS / O elemental analyzer, etc. Different methods are applicable to different types of polar groups and different compound matrices. For example, the titration method is suitable for dissociable groups, while infrared spectroscopy can be used for qualitative or quantitative analysis through characteristic peaks.

[0034] In a preferred embodiment, the functional groups of the first organic fluorescent compound include one or more of benzotriazole group, triazine group, benzophenone group, carbazole group, quinoxaline group, benzimidazole group and triphenylamine group. The above types of organic fluorescent compounds can cooperate with the above specific polar groups to enhance the intermolecular force, stabilize the light conversion agent, further improve the ultraviolet to visible light conversion efficiency, reduce migration, and maintain the long-term high performance of the encapsulation film.

[0035] In a preferred embodiment, the weight-average molecular weight of the first light conversion agent is 200 to 5000 g / mol, preferably 1000 to 5000 g / mol. The light conversion agent with a weight-average molecular weight within the above range has a more stable molecular structure, which is more conducive to forming a good dispersion state in the polymer matrix, thereby being able to further reduce agglomeration, ensure the uniform distribution of the light conversion agent, and improve the light conversion effect. The light conversion agent with a lower molecular weight may have stronger migration in the encapsulation material and is prone to precipitation, affecting the light conversion stability and efficiency. The light conversion agent with a higher molecular weight may be difficult to disperse uniformly due to steric hindrance effects, easily reducing the optical transparency, and at the same time, the cost may increase.

[0036] In a preferred embodiment, the first organic fluorescent compound includes an organic small molecule light conversion agent and an organic polymer light conversion agent; preferably, the organic small molecule light conversion agent includes one or more of benzotriazole and its derivatives, triazine and its derivatives, benzophenone and its derivatives, carbazole and its derivatives, quinoxaline and its derivatives, benzimidazole and its derivatives, and triphenylamine and its derivatives; preferably, the copolymer monomer of the organic polymer light conversion agent contains a functional group and a polymerizable group in its structure, and the functional group includes one or more of triazole group, triazine group, benzophenone group, carbazole group, quinoxaline group, benzimidazole group, and triphenylamine group, and the polymerizable group includes one or more of alkenyl, ester group, hydroxyl group, and carboxyl group.

[0037] In a preferred embodiment, the first light conversion agent is one or more of. The light conversion agents of the above types are not easy to precipitate and migrate from the encapsulation adhesive film, and the light conversion efficiency and stability of the encapsulation adhesive film are high.

[0038] In formula (1), i is any integer from 0 to 100;

[0039] L i independently selected from any one of substituted or unsubstituted alkylene, substituted or unsubstituted alkenylene, substituted or unsubstituted arylene, and substituted or unsubstituted heteroarylene;

[0040] group;

[0041] R1 and R'1 are each independently selected from substituted or unsubstituted C1-C containing one or more of a polar group such as an acid anhydride group, triallyl isocyanurate group, acrylic group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group, and glycidyl group 20 segment;

[0042] R2, R3, R4, and R'4 are each independently selected from H, substituted or unsubstituted C1-C 20 alkyl, substituted or unsubstituted C2-C20 heteroalkyl, substituted or unsubstituted C2 - C 20 alkenyl, substituted or unsubstituted C6 - C 40 aryl, substituted or unsubstituted C4 - C 40 heteroaryl, substituted or unsubstituted C2 - C 20 ester group, C1 - C 20 hydrocarbon - substituted or unsubstituted amino group, C6 - C 30 aryl - substituted or unsubstituted amino group, C1 - C 20 hydrocarbon - substituted or unsubstituted acylamino group, substituted or unsubstituted C3 - C 20 cyclic acylamino group, substituted or unsubstituted C3 - C 20 cyclic imide group, C1 - C 20 hydrocarbon - substituted or unsubstituted carboxyl group, C1 - C 20 hydrocarbon - substituted or unsubstituted carbonyl group, C1 - C 20 Any one of hydrocarbon - substituted or unsubstituted hydroxyl groups.

[0043] Naphthotriazole has more substitution sites, which is more conducive to adjusting and optimizing the performance of the light conversion agent. Therefore, when naphthotriazole is used as the luminescent core and groups with electron - donating ability, such as aryl, heteroaryl, amino, etc., are used as auxochromes on the periphery of the naphthotriazole ring, it is easy for naphthotriazole molecules to have the characteristics of high luminescence and strong absorption. Further, when the H atoms on naphthotriazole are substituted with some alkyl, alkenyl, ester chains, especially long - chain substituents, not only can the solubility of the light conversion agent be effectively improved, but especially the alkyl substituents can also form a protective film on the periphery of the luminescent group, thereby improving the light stability of the light conversion film material. At the same time, the presence of these alkyl substituents can also avoid the luminescence quenching phenomenon caused by the stacking of polycyclic aromatic hydrocarbons, and then improve the overall luminescence efficiency of the light conversion film material.

[0044] In formula (2), for the triazine - type organic light conversion agent,

[0045] R5, R6, and R7 are each independently selected from segments of C1 - C20 of one or more of polar groups such as maleic anhydride group, triallyl isocyanurate group, acrylic acid group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group, and glycidyl group. With the triazine structure as the core and modifying the substituent structure on the periphery of the triazine structure, its maximum absorption peak is between 360 - 400 nm, the emission wavelength is greater than 400 nm, showing bright dark blue or blue fluorescence, having a relatively high light conversion efficiency, and not easily turning yellow under long - term ultraviolet light irradiation, having good light stability,

[0046] It can better meet the different requirements of different manufacturers' photovoltaic devices for the wavelength - converting film.

[0047] In formula (3), the benzotriazole-based organic light conversion agent,

[0048] R8, R9, R 10 are each independently selected from one or more of a polar group such as maleic anhydride group, triallyl isocyanurate group, acrylic acid group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group, and glycidyl group, and are C1-C20 chain segments.

[0049] In order to be more effectively dispersed in the matrix resin, reduce the agglomeration phenomenon, prevent the migration of the light conversion agent during long-term use or in harsh environments, ensure the long-term light conversion performance and service life of the encapsulation material, and at the same time not sacrifice the optical transparency and mechanical strength of the encapsulation material, in a preferred embodiment, the weight percentage content of the first light conversion agent in the light conversion layer is 0.01-2%. If the content of the light conversion agent is too low, it may mean that the amount of the light conversion agent is not sufficient to significantly improve the light conversion effect of the encapsulation material, while if the content is too high, the following problems may occur: First, the excessive light conversion agent is prone to agglomeration during the processing process, forming light scattering centers, reducing the optical transparency and light transmittance of the encapsulation material; Second, the high content of the light conversion agent may have poor compatibility with the matrix resin, resulting in a decrease in material properties, such as a reduction in mechanical strength and poor weather resistance; Finally, the use of too much light conversion agent may also increase the production cost of the encapsulation material, while the improvement of the light conversion efficiency is relatively limited.

[0050] In order to further enhance the stability and durability of the light conversion effect, in a preferred embodiment, the light conversion layer further includes a modified matrix resin, and the modified matrix resin is a second matrix resin graft-modified with a second light conversion agent. Under the above conditions, the migration of the light conversion agent can be further inhibited, thereby further improving the overall efficiency and reliability of the solar cell module.

[0051] In a preferred embodiment, the grafting rate of the second light conversion agent on the second matrix resin is 0.1-10%. This grafting rate range can optimize the combination of the light conversion agent and the matrix resin, further efficiently convert light while maintaining good physical properties of the adhesive film. The grafting rate of the light conversion agent on the matrix resin is calculated by the elemental analysis method (CHNS / O) based on the content of characteristic elements (such as N, S) in the grafting monomer; grafting rate (%) = (C 接枝后 -C 原树脂 ) / C 单体理论 ×100%, in the formula, C is the mass fraction of characteristic elements such as N, S in the light conversion agent.

[0052] In order to further stabilize the light conversion efficiency, improve the light absorption of solar modules, and enhance durability and performance, in a preferred embodiment, the second light conversion agent is a second organic fluorescent compound containing a second polar group; more preferably, the second polar group includes one or more of maleic anhydride group, triallyl isocyanurate group, acrylic acid-containing group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group, and glycidyl group; more preferably, the functional groups of the second organic fluorescent compound include one or more of benzotriazole group, triazine group, benzophenone group, carbazole group, quinoxaline group, benzimidazole group, and triphenylamine group.

[0053] In a preferred embodiment, by weight percentage, the light conversion layer comprises 10 - 93% of a first matrix resin, 5 - 89% of a modified matrix resin, and 0.01 - 2% of a first light conversion agent. Under the above conditions, it is possible to more effectively balance the light conversion performance and the physical stability of the adhesive film, while achieving high-efficiency light conversion, more effectively maintaining the flexibility and bonding strength of the material, and thus being more conducive to improving the reliability and efficiency of solar modules.

[0054] In a preferred embodiment, the first matrix resin and the second matrix resin independently include vinyl polymers. Preferably, the vinyl polymer is one or more of ethylene-vinyl acetate, polyethylene, hyperbranched polyethylene, and ethylene-α-olefin copolymer; more preferably, the density of polyethylene is 0.91 - 0.93 g / cm 3 ; more preferably, the degree of branching of hyperbranched polyethylene is 40 - 140 branches / 1000 carbons; more preferably, the ethylene-α-olefin copolymer includes one or more of ethylene-butene copolymer, ethylene-octene copolymer, ethylene-hexene copolymer, and ethylene-propylene-hexene copolymer. The above materials have good flexibility and excellent dispersion properties, which are more conducive to the uniform distribution of the light conversion agent, thereby further improving the light conversion efficiency.

[0055] In a preferred embodiment, the melting point of the vinyl polymer is 86 - 125 °C, more preferably 90 - 120 °C, and further preferably 90 - 115 °C. The vinyl polymer under the above conditions has stronger stability during processing, is easier to mold, and is more likely to maintain its structural integrity in the use environment.

[0056] In a preferred embodiment, the first matrix resin and the second matrix resin also independently include one or more of ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethyl-methyl acrylate copolymer, ethylene-butyl acrylate copolymer, polyvinyl butyral, low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, polypropylene, ionomer, and silicone. Ionomer, also known as ion cross-linked polymer or ionomer, is obtained by introducing metal ions (such as sodium, potassium, zinc, magnesium, etc.) into the main chain of the copolymer of monomers such as ethylene and acrylic acid for cross-linking. In a preferred embodiment, the ionomer includes the sodium salt or zinc salt of ethylene (meth) acrylic polymer, wherein the ethylene (meth) acrylic polymer is ethylene acrylic polymer and / or ethylene methyl acrylic polymer. Under the above conditions, the weather resistance and barrier properties of the matrix resin can be further enhanced, protecting the internal light conversion agent from environmental factors, which is more conducive to improving the stable light conversion effect and high transmittance of the encapsulation material during long-term use.

[0057] In order to further improve the conversion of ultraviolet rays, reflection of infrared rays, barrier of moisture, and cut-off effect of ultraviolet light of the encapsulation film, while maintaining its good flexibility and processability, in a preferred embodiment, the thickness of the light conversion layer is 50-500 μm; and / or, the encapsulation film further includes an infrared high-reflection layer located on at least one side of the light conversion layer. The infrared high-reflection layer includes a third matrix resin and infrared high-reflection fillers, and the infrared high-reflection fillers include one or more of indium tin oxide, antimony tin oxide, cadmium selenide, and cadmium telluride; the above infrared high-reflection fillers have special structures, relatively wide band gaps, high conductivity, good optoelectronic properties, moderate free electron density, and high transmittance in the visible light region. Collaborating with other component materials, they can effectively achieve different reflectivities of different materials for infrared rays of different wavelengths, while absorbing, reflecting, and blocking ultraviolet rays, allowing visible light to pass through, and reflecting near-infrared rays, so as to achieve a heat insulation effect. In a preferred embodiment, the thickness of the infrared high-reflection layer is 50-250 μm. Preferably, based on the weight percentage, the infrared high-reflection fillers account for 0.01-5% of the third matrix resin.

[0058] In a preferred embodiment, the encapsulation film further includes an ultraviolet cut-off layer located on at least one side of the light conversion layer; and / or, the thickness of the ultraviolet cut-off layer is 50-250 μm. In a preferred embodiment, the encapsulation film further includes a barrier layer located between the light conversion layer and the ultraviolet cut-off layer. The barrier layer includes one or more of POE, PP, PE, and PET, preferably PET; and / or, the thickness of the barrier layer is 50-250 μm. In a preferred embodiment, the number of layers of the encapsulation film is 2-5 layers.

[0059] In a preferred embodiment, the ultraviolet cut-off layer comprises a fourth matrix resin and an ultraviolet absorber; the fourth matrix resin is selected from one or more of ethylene-vinyl acetate, polyethylene, hyperbranched polyethylene, and ethylene-α-olefin copolymer; preferably, the ultraviolet absorber is selected from ethyl 2-cyano-3,3-diphenylacrylate, ethylhexyl p-methoxycinnamate, isooctyl p-methoxycinnamate, dimethyl 4-methoxybenzylidenemalonate, N-(2-ethoxyphenyl)-N'-(4-ethylphenyl)oxalamide, 2-(2'-hydroxy-5'-tert-octylphenyl)benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, n-hexadecyl 2-(4,6-di-tert-butyl-3,5-dihydroxybenzoyl)benzoate, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-n-hexyloxyphenol, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, or polysiloxane. Preferably, based on the weight percentage, the ultraviolet absorber accounts for 0.01 to 5% of the fourth matrix resin.

[0060] In a preferred embodiment, the light conversion layer, the infrared highly reflective layer, the ultraviolet cut-off layer, and the barrier layer can also independently add additives such as co-crosslinking agents, tackifiers, and hindered amine stabilizers. Specifically, in the present application, the co-crosslinking agent is a commonly used co-crosslinking agent in the art, including but not limited to any one or more of allyl isocyanurate, triallyl cyanurate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and pentaerythritol triacrylate. In the present application, the tackifier is a commonly used tackifier in the art, including but not limited to any one or more of γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-glycidyletheroxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxysilane), and allyltrimethoxysilane. In the present application, the hindered amine stabilizer is a commonly used stabilizer in the art, including but not limited to any one or more of cetyl 3,5-di-tert-butyl-4-hydroxybenzoate, tris(1,2,2,6,6-pentamethyl-4-piperidyl) phosphite, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, polymer of succinic acid and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol, N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,6-hexanediamine, and polymer of morpholine-2,4,6-trichloro-1,3,5-triazine.

[0061] As mentioned above, the design of polar group capping and no cross-linking agent can significantly improve the light conversion performance and visible light transmittance of the encapsulation film. In a preferred embodiment, the average ultraviolet transmittance of the encapsulation film at 290-380 nm is ≤2%, and the light transmittance at 400-700 nm is ≤91%.

[0062] In another typical embodiment of the present invention, an encapsulation device is further provided, which includes an electronic component, and at least one surface of the electronic component is in contact with the above-mentioned encapsulation film. As mentioned above, the encapsulation film capped with polar groups can improve the stability and distribution uniformity of the light conversion agent, effectively protect the electronic component from ultraviolet damage, and at the same time enhance the light energy conversion efficiency; the design without cross-linking agent can retain the high transparency and good flexibility of the film, avoid light scattering, and simplify the production process; the encapsulation device of the present application has good comprehensive performance and long service life.

[0063] In a preferred embodiment, the electronic component includes one or more of a solar cell, a liquid crystal panel, a field emission device, a plasma display device, and a touch screen.

[0064] In another typical embodiment of the present invention, a solar cell module is further provided, which includes a solar cell, and at least one surface of the solar cell is in contact with the above-mentioned encapsulation film. As mentioned above, polar group capping can improve the stability of the light conversion agent, optimize the ultraviolet light conversion, protect the solar cell, and enhance the power generation efficiency; the design without cross-linking agent can maintain the high light transmittance of the film, simplify the manufacturing, and reduce the internal stress; the solar cell module of the present application has excellent optoelectronic performance, long service life, and high overall efficiency of the module.

[0065] In a preferred embodiment, a metal wire is attached to the surface of the solar cell in contact with the encapsulation film.

[0066] Typical but non-limiting, the weight percentage content of the first polar group in the first light conversion agent is 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15% or a range value composed of any two of these values.

[0067] Typical but non-limiting, the weight average molecular weight of the first light conversion agent is 200 g / mol, 300 g / mol, 400 g / mol, 500 g / mol, 1000 g / mol, 2000 g / mol, 3000 g / mol, 4000 g / mol, 5000 g / mol or a range value composed of any two of these values.

[0068] Typically but not limitedly, the weight percentage of the first light conversion agent in the light conversion layer is 0.01%, 0.05%, 0.1%, 0.5%, 1%, 1.5%, 2% or a range value composed of any two of these values.

[0069] Typically but not limitedly, the grafting rate of the second light conversion agent on the second matrix resin is 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10% or a range value composed of any two of these values.

[0070] Typically but not limitedly, by weight percentage, in the light conversion layer, the first matrix resin accounts for 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 93% or a range value composed of any two of these values, the modified matrix resin accounts for 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 89% or a range value composed of any two of these values, and the first light conversion agent accounts for 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2% or a range value composed of any two of these values.

[0071] The following further describes the present application in detail with specific embodiments, and these embodiments should not be construed as limiting the scope claimed by the present application.

[0072] Unless otherwise specified, the following “%” all refers to “wt%”.

[0073] Example 1

[0074] An encapsulation film includes a light conversion layer, and the light conversion layer includes: 99.5% of the first matrix resin ethylene-butene copolymer (melting point 95°C) and 0.5% of the first light conversion agent. The first light conversion agent is benzotriazole capped with butenamide group (the weight-average molecular weight of the first light conversion agent is 204 g / mol), and the weight percentage of the butenamide group in the first light conversion agent is 0.5%. The thickness of the light conversion layer is 0.45 mm.

[0075] Example 2

[0076] The difference from Example 1 is only that:

[0077] The first light conversion agent is benzotriazole capped with octenamide group (the weight-average molecular weight of the first light conversion agent is 450 g / mol), and the weight percentage of the octenamide group in the first light conversion agent is 8%.

[0078] Example 3

[0079] The difference from Example 1 is only that:

[0080] The first light conversion agent is benzotriazole capped with trimethylolpropane triacrylate (the weight-average molecular weight of the first light conversion agent is 1000 g / mol), and the weight percentage of trimethylolpropane triacrylate in the first light conversion agent is 4%.

[0081] Example 4

[0082] The difference from Example 1 is only that:

[0083] The first light conversion agent is benzotriazole capped with butyl methacrylate (the weight-average molecular weight of the first light conversion agent is 800 g / mol), and the weight percentage of butyl methacrylate in the first light conversion agent is 1%.

[0084] Example 5

[0085] The difference from Example 1 is only that:

[0086] The first light conversion agent is benzotriazole capped with trimethylolpropane triacrylate (weight-average molecular weight is 1000 g / mol) and benzotriazole capped with octenamide (weight-average molecular weight is 450 g / mol), the weight percentage of trimethylolpropane triacrylate in the first light conversion agent is 3%, and the weight percentage of octenamide in the first light conversion agent is 2%.

[0087] Example 6

[0088] The difference from Example 1 is only that:

[0089] The first light conversion agent is benzotriazole capped with butenamide, and the weight percentage of butenamide in the first light conversion agent is 0.1%.

[0090] Example 7

[0091] The difference from Example 1 is only that:

[0092] The first light conversion agent is benzotriazole capped with butenamide, and the weight percentage of butenamide in the first light conversion agent is 15%.

[0093] Example 8

[0094] The difference from Example 1 is only that:

[0095] The first light conversion agent is polybenzotriazole capped with butenamide (the weight-average molecular weight of the first light conversion agent is 1000 g / mol).

[0096] Example 9

[0097] The difference from Example 1 is only that:

[0098] The first light conversion agent is a butenamide group-terminated polytriazine (the weight-average molecular weight of the first light conversion agent is 2000 g / mol).

[0099] Example 10

[0100] The difference from Example 1 is only that:

[0101] The first light conversion agent is a butenamide group-terminated polybenzimidazole (the weight-average molecular weight of the first light conversion agent is 4500 g / mol).

[0102] Example 11

[0103] An encapsulating adhesive film includes a light conversion layer, and the light conversion layer includes: 80% of a first matrix resin ethylene-butene copolymer (melting point 95°C), 19.5% of a modified matrix resin, and 0.5% of a first light conversion agent. Among them, the first light conversion agent is a butenamide group-terminated benzotriazole (the weight-average molecular weight of the first light conversion agent is 204 g / mol), and the weight percentage of the butenamide group in the first light conversion agent is 0.5%; the modified matrix resin is a second matrix resin graft-modified with a second light conversion agent. Among them, the second light conversion agent is an epoxy group-terminated benzotriazole (the weight-average molecular weight of the second light conversion agent is 1000 g / mol), and the weight percentage of the epoxy group in the second light conversion agent is 1%. The second matrix resin is an ethylene-hexene copolymer (melting point 92°C), and the grafting rate of the second light conversion agent on the second matrix resin is 5%.

[0104] The thickness of the light conversion layer is 0.45 mm.

[0105] Example 12

[0106] The difference from Example 11 is only that:

[0107] In the modified matrix resin, the second light conversion agent is a benzotriazole derivative terminated with triallyl isocyanurate group (the second weight-average molecular weight is 1500 g / mol), and the weight percentage of the triallyl isocyanurate group in the second light conversion agent is 1%. The second matrix resin is selected from ethylene-hexene copolymers (melting point 92°C), and the grafting rate of the second light conversion agent on the second matrix resin is 5%.

[0108] Example 13

[0109] The difference from Example 11 is only that:

[0110] In the modified matrix resin, the grafting rate of the second light conversion agent on the second matrix resin is 1%.

[0111] Example 14

[0112] The difference from Example 11 is only that:

[0113] An encapsulation film, including a light conversion layer, the light conversion layer comprising: 10.99% ethylene-butene copolymer (melting point 95 °C), 89% modified matrix resin, and 0.01% first light conversion agent.

[0114] Example 15

[0115] The difference from Example 11 is only that:

[0116] An encapsulation film, including a light conversion layer, the light conversion layer comprising: 90% ethylene-butene copolymer (melting point 95 °C), 8% modified matrix resin, and 2% first light conversion agent.

[0117] Example 16

[0118] The difference from Example 1 is only that:

[0119] The encapsulation film sequentially includes a light conversion layer, a barrier layer, and an ultraviolet cut-off layer. Among them, the thickness of the light conversion layer is 0.2 mm; the ultraviolet cut-off layer includes 100 parts by weight of ethylene-vinyl acetate resin and 0.1 part by weight of ultraviolet absorber N-(2-ethoxyphenyl)-N'-(4-ethylphenyl)-oxalamide, with a thickness of 150 μm; the barrier layer is PET with a thickness of 100 μm.

[0120] Comparative Example 1

[0121] The difference from Example 1 is only that:

[0122] The first light conversion agent is benzotriazole.

[0123] Comparative Example 2

[0124] The difference from Example 1 is only that:

[0125] The light conversion layer includes crosslinking agent isopropyl percarbonate tert-butyl, with a content of 0.2%.

[0126] The above encapsulation films are respectively assembled into solar modules, specifically including the following steps: sequentially arranging a front plate glass, the above encapsulation film, a silicon heterojunction cell (Huacheng cell), an ultraviolet-transmissive encapsulation film (Foster F406P), and a back plate glass from bottom to top to obtain a stack, and then placing the stack in a vacuum laminator and laminating at 145 °C for 15 min to obtain a solar module. Each time the obtained module has the same conditions except for the upper encapsulation film being different.

[0127] The characteristics and performances of the encapsulation films prepared in the above examples and comparative examples are tested, and the test results are shown in Table 1.

[0128] Test method:

[0129] Light transmittance: Measured in accordance with GB / T 2410-2008. The average ultraviolet transmittance of the encapsulation film at 290-380 nm and the light transmittance at 400-700 nm were tested using an ultraviolet-visible spectrophotometer.

[0130] Aging test: The upper and lower surfaces of the light conversion film were laminated with glass layers respectively to obtain a pre-pressed component, and UV300 aging test was carried out in a multi-fold ultraviolet aging chamber (power 142W, temperature 70°C). The yellowing index (ΔYI) of the pre-pressed component before and after the aging test was measured in accordance with the national standard GB2409 "Test Method for Yellow Index of Plastics".

[0131] Light conversion efficiency test: Using the wavelength corresponding to the maximum absorption peak measured by the ultraviolet spectrometer as the excitation wavelength, the absolute quantum efficiency of the light conversion agent was tested at room temperature using an integrating sphere equipped with a Horiba FL-3 fluorescence spectrometer.

[0132] Test method for the migration distance of the light conversion agent: Take the newly prepared solar cell module, let it stand at 25°C for 6h respectively, and then bake it in an oven at 120°C for 288h, and then evaluate the distance (unit / cm) of the light conversion agent migrating from the edge of the battery cell to the back of the battery cell. The greater the distance, the more serious the migration of the light conversion agent.

[0133] Table 1

[0134]

[0135] As can be seen from the above, compared with the comparative examples, in each embodiment of the present invention, by using a system without a cross-linking agent in the light conversion layer of the encapsulation film and selecting an organic fluorescent compound capped with a polar group as the light conversion agent, the precipitation and migration of the light conversion agent are effectively avoided, thereby improving the light conversion efficiency and stability of the encapsulation film, and further being beneficial to the power generation efficiency and long-term reliability of the solar cell module in the ultraviolet environment. Moreover, the production process is simplified, the manufacturing cost is reduced, which is beneficial to the development of N-type battery technology, especially the encapsulation technology of HJT and TOPCon battery modules.

[0136] In addition, it can be seen that when each process parameter is within the preferred range of the present invention, the comprehensive effect of the encapsulation film is better.

[0137] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An encapsulation film, characterized in that, It includes a light conversion layer, and the light conversion layer includes a first matrix resin and a first light conversion agent. The light conversion layer does not contain a crosslinking agent. The first light conversion agent is a first organic fluorescent compound containing a first polar group.

2. The encapsulation adhesive film according to claim 1, wherein the first polar group includes one or more of maleic anhydride group, triallyl isocyanurate group, acrylic acid-containing group, hydroxyl group, ester group, carbonyl group, amide group, pyridyl group, epoxy group, pyrrolidone group, and glycidyl group; preferably amide group and / or glycidyl group.

3. The encapsulation adhesive film according to claim 2, wherein the acrylic acid-containing group includes acrylic group and / or methacrylic group; and / or, the ester group includes acrylate group; preferably, the acrylate group includes one or more of alkyl acrylate group, alkyl methacrylate group, phenyl acrylate group, phenyl methacrylate group, benzyl acrylate group, trimethylolpropane triacrylate group, pentaerythritol triacrylate group, and ethoxylated trimethylolpropane triacrylate group; more preferably, the alkyl acrylate group includes one or more of methyl acrylate group, ethyl acrylate group, butyl acrylate group, cyclohexyl acrylate group, and 2-ethylhexyl acrylate group; more preferably, the alkyl methacrylate group includes one or more of methyl methacrylate group, ethyl methacrylate group, butyl methacrylate group, cyclohexyl methacrylate group, and 2-ethylhexyl methacrylate group; and / or, the amide group includes one or more of acrylamide group, methacrylamide group, N-methylmethacrylamide group, N-ethylacrylamide group, N-isopropylacrylamide group, N-tert-butylacrylamide group, N-hydroxymethylacrylamide group, N-hydroxyethylacrylamide group, N-(2-hydroxypropyl)acrylamide group, N,N'-methylenebisacrylamide group, maleimide group, oleic acid amide group, 9-hexadecenamide group, N-(2-hydroxyethyl)-undec-10-enamide group, 9-tetradecenamide group, 9-dodecenamide group, 9-decenamide group, octenamide group, heptenamide group, hexenamide group, pentenamide group, and butenamide group.

4. The encapsulation adhesive film according to any one of claims 1 to 3, wherein the weight percentage content of the first polar group in the first light conversion agent is 0.1 to 15%.

5. The encapsulation adhesive film according to any one of claims 1 to 4, wherein the functional groups of the first organic fluorescent compound include one or more of benzotriazole group, triazine group, benzophenone group, carbazole group, quinoxaline group, benzimidazole group, and triphenylamine group; and / or, the weight average molecular weight of the first light conversion agent is 200 to 5000 g / mol, preferably 1000 to 5000 g / mol; and / or, the first organic fluorescent compound includes an organic small molecule light conversion agent and an organic polymer light conversion agent. Preferably, the organic small molecule light conversion agent includes one or more of benzotriazole and its derivatives, triazine and its derivatives, benzophenone and its derivatives, carbazole and its derivatives, quinoxaline and its derivatives, benzimidazole and its derivatives, and triphenylamine and its derivatives; Preferably, the copolymerization monomer of the organic polymer light conversion agent contains a functional group and a polymerizable group in its structure. The functional group includes one or more of a triazole group, a triazine group, a benzophenone group, a carbazole group, a quinoxaline group, a benzimidazole group, and a triphenylamine group. The polymerizable group includes one or more of an alkenyl group, an ester group, a hydroxyl group, and a carboxyl group; and / or, The weight percentage content of the first light conversion agent in the light conversion layer is 0.01 to 2%.

6. The encapsulation adhesive film according to any one of claims 1 to 5, wherein The light conversion layer further includes a modified matrix resin, and the modified matrix resin is a second matrix resin graft-modified with a second light conversion agent. Preferably, the grafting rate of the second light conversion agent on the second matrix resin is 0.1 to 10%; Preferably, the second light conversion agent is a second organic fluorescent compound containing a second polar group; more preferably, the second polar group includes one or more of a maleic anhydride group, a triallyl isocyanurate group, an acrylic acid-containing group, a hydroxyl group, an ester group, a carbonyl group, an amide group, a pyridyl group, an epoxy group, a pyrrolidone group, and a glycidyl group; more preferably, the functional group of the second organic fluorescent compound includes one or more of a benzotriazole group, a triazine group, a benzophenone group, a carbazole group, a quinoxaline group, a benzimidazole group, and a triphenylamine group; Preferably, by weight percentage, the light conversion layer includes 10 to 93% of the first matrix resin, 5 to 89% of the modified matrix resin, and 0.01 to 2% of the first light conversion agent.

7. The encapsulation adhesive film according to any one of claims 1 to 6, wherein The first matrix resin and the second matrix resin each independently include a vinyl polymer; Preferably, the vinyl polymer is one or more of ethylene-vinyl acetate, polyethylene, hyperbranched polyethylene, and ethylene-α-olefin copolymer; more preferably, the density of the polyethylene is 0.91-0.93 g / cm 3 ; more preferably, the degree of branching of the hyperbranched polyethylene is 40-140 branches / 1000 carbons; more preferably, the ethylene-α-olefin copolymer includes one or more of ethylene-butene copolymer, ethylene-octene copolymer, ethylene-hexene copolymer, and ethylene-propylene-hexene copolymer; preferably, the melting point of the vinyl polymer is 86-125 °C, more preferably 90-120 °C, and further preferably 90-115 °C; Preferably, the first matrix resin and the second matrix resin also each independently include one or more of an ethylene-acrylic acid copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-methyl methacrylate copolymer, an ethyl-methyl acrylate copolymer, an ethylene-butyl acrylate copolymer, polyvinyl butyral, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, ionomer, and silicone.

8. The encapsulation adhesive film according to any one of claims 1 to 7, wherein The thickness of the light conversion layer is 50 to 500 μm; and / or, The encapsulation adhesive film further includes an infrared high reflection layer located on at least one side of the light conversion layer. The infrared high reflection layer includes a third matrix resin and an infrared high reflection filler. The infrared high reflection filler includes one or more of indium tin oxide, tin antimony oxide, cadmium selenide, and cadmium telluride; and / or, the thickness of the infrared high reflection layer is 50 to 250 μm.

9. The encapsulation adhesive film according to any one of claims 1 to 8, wherein The encapsulation film further comprises an ultraviolet cut-off layer, and the ultraviolet cut-off layer is located on at least one side of the light conversion layer; and / or, the thickness of the ultraviolet cut-off layer is 50 to 250 μm; Preferably, the encapsulation film further comprises a barrier layer, the barrier layer is located between the light conversion layer and the ultraviolet cut-off layer, and the barrier layer comprises one or more of POE, PP, PE, and PET; and / or, the thickness of the barrier layer is 50 to 250 μm; and / or, The number of layers of the encapsulation film is 2 to 5 layers.

10. The encapsulation film according to any one of claims 1 to 9, wherein The average ultraviolet transmittance of the encapsulation film at 290 to 380 nm is ≤2%, and the light transmittance at 400 to 700 nm is ≤91%.

11. An encapsulation device includes electronic components, characterized in that, At least one surface of the electronic component is in contact with the encapsulation film according to any one of claims 1 to 10; Preferably, the electronic component comprises one or more of a solar cell, a liquid crystal panel, a field emission device, a plasma display device, and a touch screen.

12. A solar cell module, comprising a solar cell, characterized in that, At least one surface of the solar cell is in contact with the encapsulation film according to any one of claims 1 to 10; Preferably, a metal wire is attached to the surface of the solar cell in contact with the encapsulation film.

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