CN113061397A

CN113061397A - Packaging adhesive film and photovoltaic module

Info

Publication number: CN113061397A
Application number: CN202110512811.XA
Authority: CN
Inventors: 魏梦娟; 王富成; 周光大
Original assignee: Foster Jiaxing New Material Co ltd
Current assignee: Foster Jiaxing New Material Co ltd
Priority date: 2021-05-11
Filing date: 2021-05-11
Publication date: 2021-07-02
Anticipated expiration: 2041-05-11
Also published as: CN113061397B

Abstract

The invention provides a packaging adhesive film and a photovoltaic module. The packaging adhesive film comprises: the organic film comprises a first film base body and a plurality of organic matter high-refraction-rate parts, wherein the organic matter high-refraction-rate parts are arranged on one surface of the first film base body at intervals, the organic matter high-refraction-rate parts are arranged in one-to-one correspondence with the packaged solar cells, the refraction rate of the first film base body is 1.45-1.50, the refraction rate of the organic matter high-refraction-rate parts is 1.49-1.8, and the refraction rate of the organic matter high-refraction-rate parts is higher than that of the first film base body. This application sets up the higher material of refracting index on a surface of first glued membrane base member to match the refracting index of battery piece better, effectively promoted light utilization efficiency. Simultaneously, because the organic matter high refractive index portion of the encapsulation glued membrane of this application sets up on the surface of first glued membrane base member, this structure is more stable, has avoided the additive reunion and the unable problem that effectively improves of refracting index that leads to.

Description

Packaging adhesive film and photovoltaic module

Technical Field

The invention relates to the technical field of photovoltaic module packaging adhesive films, in particular to a packaging adhesive film and a photovoltaic module.

Background

In the photovoltaic cell, sunlight penetrates through the upper layer of toughened glass and the packaging adhesive film, and light energy is converted into electric energy on the crystal silicon wafer. The refractive index of the traditional material for packaging the solar module is smaller than that of glass, so that the refraction angle is correspondingly enlarged after sunlight is transmitted through the EVA from the glass, and the following problems are caused: the incident angle of light incident on the cell plate is increased, and the corresponding loss of reflected light and diffuse reflection light is increased. Wherein the refractive index of the glass is 1.52, and the refractive index of the silicon cell sheet is 3.8. The refractive index of the packaging adhesive film is required to be 2.34 according to the formula. The refractive index of the common packaging materials is less than 1.5, and the requirement cannot be met, so that the light utilization rate is greatly influenced.

At present, the method for improving the refractive index of the packaging adhesive film mainly comprises the step of adding inorganic nano materials with high refractive index into matrix resin. However, the inorganic nano material with high refractive index is directly added into the adhesive film, and the nano material is easy to agglomerate or deposit in the adhesive film to cause phase separation due to the reasons of higher surface energy of the nano particles, unmatched polarity and the matrix adhesive film and the like, so that the adhesive film structure is unstable, and the nano material cannot play a role in improving the refractive index of the adhesive film, so that the overall refractive index of the adhesive film is not obviously improved. In addition, the synthesis of small nanoparticles that can maintain transparency, have small particle size and are suitable for encapsulating films also has great difficulty in production.

In order to solve the problem of easy agglomeration of the nano-materials in the prior art, a dispersing agent and a silane coupling agent are usually added to improve the dispersibility of the nano-materials in the adhesive film. However, when the dispersant is used to improve the dispersibility of the nanomaterial, a large amount of the dispersant needs to be added to coat the surface of the nanomaterial particles, and the complexing of the dispersant and the nanomaterial degrades or impairs the performance of the nanoparticles to be developed.

The effect of improving the dispersibility of nanoparticles using a silane coupling agent is also limited. On one hand, even if the silane coupling agent is used, complete Si-O-M bonds are difficult to form between the nano particles and the adhesive film substrate, so that the coupling effect is not obvious, on the other hand, the silane coupling agent also increases the amount of residual hydroxyl groups on the surfaces of the nano particles, and under the action of the residual hydroxyl groups, the binding force between the nano particles is increased, so that the nano particles have the tendency of agglomeration and are difficult to decompose into primary particles. In addition, since the silane coupling agent is usually added in a secondarily aggregated state, insufficient dispersion of the organic composition nanoparticles therein also causes a problem of lowering of transparency.

In summary, although it is theoretically possible to obtain a high refractive index encapsulant film by combining nano-scale high refractive index inorganic oxide particles and a polymer. However, due to the problem of nanoparticle agglomeration, when nano-grade high-refractive-index inorganic oxide particles are added into the packaging adhesive film, the refractive index of the packaging adhesive film is difficult to increase and even tends to decrease.

In view of the above, there is a need for a high refractive index adhesive film to improve the overall efficiency of the photovoltaic module.

Disclosure of Invention

The invention mainly aims to provide a packaging adhesive film and a photovoltaic module so as to solve the problem of low refractive index of an adhesive film structure in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a packaging adhesive film including: the organic film comprises a first film base body and a plurality of organic matter high-refraction-rate parts, wherein the organic matter high-refraction-rate parts are arranged on one surface of the first film base body at intervals, the organic matter high-refraction-rate parts are arranged in one-to-one correspondence with the packaged solar cells, the refraction rate of the first film base body is 1.45-1.50, the refraction rate of the organic matter high-refraction-rate parts is 1.49-1.8, and the refraction rate of the organic matter high-refraction-rate parts is higher than that of the first film base body.

Furthermore, a plurality of grooves are formed in one surface of the first adhesive film base at intervals, the organic high-refraction-rate part is embedded in the grooves, and the thickness of the organic high-refraction-rate part is preferably the same as the depth of the grooves.

Further, the organic high-refraction-rate part is a composite layer of any one or more of a (meth) acrylate layer, an epoxy layer and a silica gel layer, preferably the silica gel layer is selected from one or more of an epoxy silica gel layer, an acrylated silica gel layer, a methyl phenyl vinyl silica gel layer, a phenyl hydrogen-containing silica gel layer, a phenyl vinyl silica gel layer and a hydroxyl-terminated methyl vinyl silica gel layer, and preferably the refractive index of the silica gel layer is 1.55-1.65; when the organic high refractive index portion (20) is preferably a (meth) acrylate layer or an epoxy layer, the raw material for forming the organic high refractive index portion includes a monomer and a photoinitiator, the monomer is preferably one or two selected from a (meth) acrylate monomer and an epoxy monomer, the (meth) acrylate monomer is preferably one or more selected from pentaerythritol tetraacrylate, tris [2- (acryloyloxy) ethyl ] isocyanurate, trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, tricyclodecane dimethanol diacrylate and tris (2-hydroxyethyl) isocyanurate diacrylate, and the epoxy monomer is preferably one or more selected from trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl ether, glycerol triglycidyl ether, triglycidyl isocyanurate, triglycidyl cyanurate, pentaerythritol triglycidyl cyanurate, a mixture thereof, and a mixture thereof, Triglycidyl hydantoin, pentaerythritol tetraglycidyl ether and one or more of dipentaerythritol tetraglycidyl ether and tetraglycidyl benzyl ethane.

Further, the organic high-refractive-index part is a high-refractive-index adhesive film with a refractive index of 1.5-1.8, the high-refractive-index adhesive film comprises a second adhesive film base body and a high-refractive-index organic dopant, the refractive index of the high-refractive-index organic dopant is 1.52-2.10, preferably 1.52-1.65, preferably the high-refractive-index organic dopant is selected from one or more of acrylate polymers, epoxy resins, fullerene polyesters, sulfur-containing resins, silicon resins, polyurethanes, polycarbonates, cyclic olefin copolymers and polyphosphazenes, preferably the acrylate polymers comprise one or more of polymethyl methacrylate resins, polyacrylate resins, polyurethane resins, epoxy acrylate diester resins and polyphenyl methacrylates, preferably the sulfur-containing resins comprise one or more of thiophene resins, fluorenyl modified polyphenylene sulfide and poly p-phenylene sulfide, preferably, in the high-refractive-index adhesive film, the mass content of the high-refractive-index organic dopant is 0.1-10%, the particle size of the high-refractive-index organic dopant is 20-100 μm, more preferably 40-100 μm, and even more preferably 60-100 μm, the resin material forming the second adhesive film matrix preferably comprises one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene-catalyzed ethylene-butylene copolymer, and the second adhesive film matrix preferably further comprises a crosslinking agent, an auxiliary crosslinking agent, an antioxidant and an ultraviolet absorbent, one or more of light stabilizer, tackifier, anticorrosive agent and pigment, preferably high refractive index adhesive film, is arranged on the first adhesive film substrate in a spraying, printing, pasting or ink-jet printing mode.

Further, the organic high refractive index portion is a high refractive index adhesive film having a refractive index of 1.52 to 2.10, preferably a high refractive index adhesive film having a refractive index of 1.52 to 1.65, the high refractive index adhesive film is selected from an acrylic polymer adhesive film, an epoxy resin adhesive film, a fullerene polyester adhesive film, a sulfur-containing resin adhesive film, a silicone resin adhesive film, and a polyurethane adhesive film, the adhesive film is one or more of a polycarbonate adhesive film, a cyclic olefin copolymer adhesive film and a polyphosphazene resin adhesive film, preferably the acrylate polymer adhesive film comprises one or more of a polymethyl methacrylate resin adhesive film, a polyacrylate resin adhesive film, a polyurethane resin adhesive film, an epoxy acrylate double-ester resin adhesive film and a polyphenyl methacrylate adhesive film, and preferably the sulfur-containing resin adhesive film comprises one or more of a thiophene resin adhesive film, a fluorenyl modified polyphenylene sulfide adhesive film and a polyphenylene sulfide adhesive film.

Further, the thickness of the packaging adhesive film is 0.1 to 1mm, preferably 0.4 to 0.5mm, the thickness of the first adhesive film substrate is preferably 350 to 500 μm, and the thickness of the organic high-refraction-rate part is preferably 50 to 200 μm.

Preferably, the organic high refractive index portion has a refractive index of 1.51 to 1.65, the refractive index of the organic high refractive index portion increases gradually in a direction away from the surface of the first adhesive film base, and the organic high refractive index portion includes a plurality of organic high refractive index layers stacked in sequence on the surface of the first adhesive film base, and the refractive index of each organic high refractive index layer increases in sequence in a direction away from the surface of the first adhesive film base.

Furthermore, a plurality of grooves are arranged on one surface of the first adhesive film base at intervals, the organic high-refraction-rate part is embedded in the grooves, the packaging adhesive film further comprises a reflection part, the reflection part and the organic high-refraction-rate part are arranged on the same surface of the first adhesive film base and are positioned at the gap of the adjacent organic high-refraction-rate parts, preferably, the surface of the organic high-refraction-rate part far away from the first adhesive film base is coplanar with the surface of the reflection part far away from the first adhesive film base, preferably, the reflection part comprises a third adhesive film base and a reflection dopant, preferably, the resin material forming the third adhesive film base comprises one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene catalyzed polyethylene, and preferably, the reflection dopant is selected from hollow glass beads, Calcium carbonate, barium sulfate, talcum powder, titanium dioxide, zinc oxide, carbon black, graphene oxide, copper-chromium black, magnesium hydroxide, aluminum oxide, magnesium oxide, boron nitride, silicon carbide, ammonium phosphate, ammonium polyphosphate, pentaerythritol, dipentaerythritol, pentaerythritol ester and melamine polyphosphate borate, wherein the reflectivity of the reflecting part in the wavelength range of 400-700 nm is preferably more than or equal to 80%, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is more than or equal to 90%.

Further, the resin material forming the first adhesive film base body comprises one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene catalyzed polyethylene, and preferably, the material forming the first adhesive film base body comprises 100 parts by weight of resin material, 0.01-3 parts by weight of cross-linking agent, 0.01-10 parts by weight of auxiliary cross-linking agent, 0-0.4 part by weight of ultraviolet light absorber, 0-0.5 part by weight of antioxidant, 0-1.0 part by weight of light stabilizer and 0-3.0 parts by weight of tackifier.

According to another aspect of the invention, a photovoltaic module is provided, which comprises a glass cover plate, a front layer packaging adhesive film, a solar cell unit, a back layer packaging adhesive film and a back layer cover plate, wherein the front layer packaging adhesive film and/or the back layer packaging adhesive film are any one of the packaging adhesive films, and the organic high-refraction-rate parts are arranged in one-to-one correspondence with the solar cells in the solar cell unit.

By applying the technical scheme of the invention, a material (namely the organic matter high-refraction-rate part) with a higher refraction rate (1.49-1.8) is arranged on one surface of the first adhesive film base, when the photovoltaic module is manufactured, the surface of the packaging adhesive film, which is provided with the organic matter high-refraction-rate part, faces the solar cell, and the organic matter high-refraction-rate part and the packaged solar cell are arranged in a one-to-one correspondence manner, so that the refraction rate of the cell is better matched, the refraction angle of incident light is reduced, the light loss caused by reflection and diffuse reflection is reduced, and the light utilization rate is effectively improved. Simultaneously, because the organic matter high refractive index portion of the encapsulation glued membrane of this application sets up on the surface of first glued membrane base member, this structure is more stable, can not appear the problem that the refracting index that leads to because of the additive reunion among the prior art can't effectively improve. In conclusion, the encapsulation adhesive film has a stable structure, can effectively improve the refractive index, and further improves the light conversion rate of the photovoltaic module consisting of the encapsulation adhesive film. And the material forming the organic matter high-refraction rate part is usually higher in price, so that the organic matter high-refraction rate part can be arranged only at the position, corresponding to the battery piece, on the packaging adhesive film, so that the requirement of improving the refractive index of the packaging adhesive film is met, the coverage area of the organic matter high-refraction rate part is reduced, and the cost is saved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 shows a top view of an encapsulating adhesive film shown in embodiment 1 according to the present invention;

FIG. 2 shows a cross-sectional view of the packaging adhesive film of FIG. 1 in the direction A-A;

fig. 3 shows a top view of the packaging adhesive film shown in embodiment 2 of the present invention; and

fig. 4 shows a cross-sectional view of the packaging adhesive film of fig. 3 in the direction of a-a.

Wherein the figures include the following reference numerals:

10. a first adhesive film base; 20. an organic high refractive index portion; 30. a reflection part.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

As described in the background of the present application, the closer the refractive index of the encapsulant film for photovoltaic cells is to 2.34, the smaller the loss of incident light, and the higher the photoelectric conversion efficiency. In the prior art, the refractive index can be improved by directly adding the high-refractive-index nano material into the adhesive film formula system, but the nano material is easy to agglomerate to cause phase separation due to overlarge polar phase difference between the nano material and the adhesive film matrix, so that the improvement effect of the refractive index cannot be expected. In order to solve the problem, the application provides a packaging adhesive film and a photovoltaic module.

In an exemplary embodiment of the present application, there is provided a packaging adhesive film, as shown in fig. 1 and 2, including: the organic film comprises a first film base body 10 and a plurality of organic matter high-refraction-rate parts 20, wherein the organic matter high-refraction-rate parts 20 are arranged on one surface of the first film base body 10 at intervals, the organic matter high-refraction-rate parts 20 are arranged in one-to-one correspondence with packaged solar cells, the refraction rate of the first film base body 10 is 1.45-1.50, the refraction rate of the organic matter high-refraction-rate parts 20 is 1.49-1.8, and the refraction rate of the organic matter high-refraction-rate parts is higher than that of the first film base body.

This application sets up the material that the refracting index is higher (1.49 ~ 1.8) on a surface of first glued membrane base member 10 (organic matter high refraction rate portion 20 promptly), when making photovoltaic module, the encapsulation glued membrane is provided with the face that organic matter high refraction rate portion 20 faces towards solar wafer, and organic matter high refraction rate portion 20 sets up with the solar wafer one-to-one that encapsulates, with the refracting index that matches the battery piece better, make the refraction angle of incident light diminish, reduce the light loss that reflection and diffuse reflection light caused simultaneously, the light utilization ratio has effectively been promoted. Meanwhile, because the organic high-refraction-rate part 20 of the packaging adhesive film is arranged on the surface of the first adhesive film base body 10, and because the organic high-refraction-rate part 20 does not contain inorganic materials with opposite polarities, the structure is more stable, and the problem that the refractive index cannot be effectively improved due to the agglomeration of additives in the prior art can be solved. To sum up, the encapsulation glued membrane of this application, stable in structure can effectively promote the refracting index, and then improves the light conversion rate by its photovoltaic module who constitutes. In addition, the material composing the organic high-refraction-rate part 20 is usually higher in price, so that the organic high-refraction-rate part 20 can be arranged only at the position on the packaging adhesive film corresponding to the battery piece, thereby not only meeting the requirement of improving the refractive index of the packaging adhesive film, but also reducing the coverage area of the organic high-refraction-rate part 20, and further saving the cost.

In some embodiments, as shown in fig. 1 and 2, a plurality of grooves are disposed on one surface of the first adhesive film substrate 10 at intervals, and the organic high-refraction-rate portion 20 is embedded in the grooves. The grooves are distributed on the surface of the first adhesive film base body 10 in a grid shape, the organic matter high-refraction-rate parts 20 are embedded in the grooves, and in the packaging state, the organic matter high-refraction-rate parts 20 correspond to the battery pieces one by one. The organic high-refraction-rate part 20 is arranged in the groove on the surface of the first adhesive film base 10, so that the two parts form three-dimensional bonding, and the bonding effect between the two parts is further enhanced. Preferably, the thickness of the organic high-refraction-rate part 20 is the same as the depth of the groove, so that the surface of the first adhesive film substrate 10, on which the organic high-refraction-rate part 20 is arranged, is a plane, the packaging process is easier to operate, and the problem that the battery piece is split due to the fact that the height difference of the surface of the packaging adhesive film is too large in the laminating process is effectively avoided. The grooves may be formed by methods commonly used in the art, such as rolling by providing protrusions complementary to the grooves on a roller, and will not be described herein.

In some embodiments, the organic high-refractive-index portion 20 is a composite layer of any one or more of a (meth) acrylate layer, an epoxy layer, and a silica gel layer, preferably, the silica gel layer is selected from one or more of an epoxidized silica gel layer, an acrylated silica gel layer, a methylphenyl vinyl silica gel layer, a phenyl hydrogen-containing silica gel layer, a phenyl vinyl silica gel layer, and a hydroxyl-terminated methyl vinyl silica gel layer, where the (meth) acrylate layer, the epoxy layer, and the silica gel layer have a high refractive index on one hand, and on the other hand, because they have organic groups, they can form a good compatibility with the first adhesive film substrate 10, and after being packaged, they stably form a high refractive index on the surface of the battery piece, so that the light utilization rate is effectively improved. In order to further improve the light utilization rate, the refractive index of the silica gel layer is preferably 1.55-1.65.

When the organic high refractive index portion (20) is preferably a (meth) acrylate layer or an epoxy layer, the raw materials for forming the organic high refractive index portion include a monomer and a photoinitiator. Preferably, the monomer is selected from one or two of a (meth) acrylate monomer and an epoxide monomer, preferably, the (meth) acrylate monomer is selected from one or more of pentaerythritol tetraacrylate, tris [2- (acryloyloxy) ethyl ] isocyanurate, trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, tricyclodecane dimethanol diacrylate and tris (2-hydroxyethyl) isocyanurate diacrylate, preferably, the epoxide monomer is selected from one or more of trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl ether, glycerol triglycidyl ether, triglycidyl isocyanurate, triglycidyl cyanurate, triglycidyl hydantoin, pentaerythritol tetraglycidyl ether and dipentaerythritol tetraglycidyl ether and tetraglycidyl benzylethane. The organic high-refraction rate part of the (methyl) acrylate monomer, the epoxide monomer and the photoinitiator can be cured and molded under the radiation of ultraviolet light.

The photoinitiator may be one or more of a free radical photoinitiator, a cationic photoinitiator, or an anionic photoinitiator. Examples of such photoinitiators are commercially available from Sartomer, Ciba-Geigy, Dow Chemical and BASF. When the (meth) acrylate monomer is included in the prepolymer, ultraviolet curing initiation may be carried out using any of radical, cationic or anionic photoinitiators. The above-mentioned radical photoinitiators may be selected by the person skilled in the art from among the radical photoinitiators known from the prior art. In order to allow the photoinitiator and the (meth) acrylate monomer to cooperate with each other to achieve a synergistic effect, the radical photoinitiator is preferably selected from (but not limited to): one or more of anthraquinone, benzophenone, substituted benzophenone, benzoin alkyl ether, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl acetone, acetophenone, substituted acetophenone, benzoyl-diphenylphosphine oxide, substituted benzoyl-diphenylphosphine oxide, dibenzoyl-diphenylphosphine oxide, and substituted dibenzoyl-diphenylphosphine oxide.

When the prepolymer includes an epoxide monomer, an ionic photoinitiator may be necessary. For example, known compounds for initiating polymerization by cationic initiators include diaryliodonium salts, triarylsulfonium salts, diaryliodonium (iodosonium) salts, dialkylphenylsulfonium salts, dialkyl (hydroxydialkylphenyl) sulfonium salts, and ferrocenium salts. The salt can be modified on the molecular chain by connecting alkyl, alkoxy, siloxy and other groups under the action of a cationic initiator. The ionic initiator of the present application may be selected from ionic initiators commonly used in the art, and in order to make the initiation effect more excellent, it is preferable that the initiator is selected from (but not limited to) one or more of iodonium (4-n-decyloxyphenyl) phenyl hexafluoroantimonate, (4-n-decyloxyphenyl) diphenyl hexafluoroantimonate sulfonium salt and S-methyl-S-n-dodecylbenzoyl methyl hexafluoroantimonate sulfonium salt. The mass concentration of the initiator in the silica gel layer is preferably 0.01-5%. Preferably, the organic high refractive index portion composition further comprises a solvent, and suitable solvents are selected from the group consisting of lower alcohols (e.g., methanol, ethanol, isopropanol, etc.), ketones (e.g., acetone), esters (e.g., ethyl acetate).

The organic high-refraction-rate part has a high refraction rate on one hand, and on the other hand, because the organic high-refraction-rate part has organic groups, a good compatible effect can be formed between the organic high-refraction-rate part and the first adhesive film base body 10, and a high refraction rate is stably formed on the surface of the battery piece after packaging, so that the light utilization rate is effectively improved. In order to further improve the light utilization efficiency, the refractive index of the organic high-refractive-index portion is preferably 1.55 to 1.65. In the method for providing the silica gel layer, reference may be made to a method for providing a high refractive index organic portion on the surface of a packaging adhesive film, which is commonly used in the prior art, and in order to provide the high refractive index organic portion as efficiently as possible on the basis of simplifying the process, the high refractive index organic portion is preferably disposed on the first adhesive film substrate 10 by spraying, printing, pasting, or inkjet printing. When the first adhesive film base 10 is provided with a groove on the surface thereof, the organic high refractive index portion may be directly provided in the groove. Of course, if the organic high-refraction-rate portion is disposed by spraying or printing, the thickness of the organic high-refraction-rate portion can be effectively controlled, even controlled at a nanometer level, so that the height difference between the organic high-refraction-rate portion and the first adhesive film substrate 10 can be substantially ignored, and the groove can be omitted from the surface of the first adhesive film substrate 10. When the inkjet printing is adopted, the organic high-refraction-rate part obtained by the inkjet printing is of a three-dimensional structure, that is, the thickness is slightly larger, so that the groove is more suitable to be arranged on the first adhesive film substrate 10.

In some embodiments, the organic high-refraction-index portion 20 is a high-refraction-index adhesive film with a refractive index of 1.5-1.8, the high-refraction-index adhesive film includes a second adhesive film base and a high-refraction-index organic dopant, and the refractive index of the high-refraction-index organic dopant is 1.52-2.10, preferably 1.52-1.65. The high-refractive-index organic dopant is added into the second adhesive film base body, so that the refractive index of the adhesive film is effectively improved, the polarity difference between the resin forming the second adhesive film base body and the resin forming the high-refractive-index organic dopant is smaller, the high-refractive-index organic dopant can be well dispersed in the second adhesive film base body, the problem of agglomeration of the inorganic dopant caused by too large polarity difference between the inorganic dopant and the adhesive film base body in the prior art is solved, and the overall structural stability of the material is improved.

In order to further improve the compatibility between the high refractive index organic dopant and the second adhesive film substrate, so that the high refractive index organic dopant can be better dispersed in the second adhesive film substrate, thereby reliably improving the refractive index of the encapsulation adhesive film, the high refractive index organic dopant is preferably selected from one or more of acrylate polymers, epoxy resins, sulfur-containing resins, silicone resins, polyurethanes, polycarbonates, cyclic olefin copolymers and polyphosphazenes. The epoxy resin can be the resin material forming the epoxy layer, the refractive index of the epoxy resin can reach 1.65, the acrylic polymer preferably comprises one or more of polymethyl methacrylate resin, polyacrylate resin, polyurethane resin, epoxy acrylate diester resin and polyphenyl methacrylate, and the sulfur-containing resin preferably comprises one or more of thiophene resin, fluorenyl modified polyphenylene sulfide and poly-p-phenylene sulfide. Preferably, the mass content of the high-refractive-index organic dopant in the high-refractive-index adhesive film is 0.1-10%, and the particle size of the high-refractive-index organic dopant is 20-100 μm, more preferably 40-100 μm, and even more preferably 60-100 μm. By further optimizing the content and the particle size of the organic dopant with high refractive index, the dispersibility of the organic dopant with high refractive index in the second adhesive film matrix is better, and the refractive index of the organic high-refractive-index part 20 is more uniform and more effectively improved.

Preferably, the resin material forming the second adhesive film base includes one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer, and metallocene-catalyzed ethylene-butene copolymer. The second adhesive film base body is formed by selecting the same resin material as the first adhesive film base body 10, so that the first adhesive film base body 10 and the adhesive film with high refractive index are tightly bonded. Preferably, the second glue film matrix further comprises one or more of a cross-linking agent, an auxiliary cross-linking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, an adhesion promoter, an anti-corrosion agent and a pigment. The specific selection of the additives can refer to the selection of each additive in the first adhesive film base 10, and is not described in detail herein.

The high refractive index adhesive film may be disposed on the first adhesive film substrate 10 by a conventional technique in the art, and is preferably disposed in one of printing, pasting and inkjet printing methods in order to form a tight bond between the high refractive index adhesive film and the first adhesive film substrate 10 while ensuring simple operation and easy implementation.

The high index of refraction film of the present application may also consist of only a high index of refraction film, which, in some embodiments, the organic matter high-refractive-index part is a high-refractive-index adhesive film with the refractive index of 1.52-2.10, preferably a high-refractive-index adhesive film with the refractive index of 1.52-1.65, the high-refractive-index adhesive film is selected from one or more of an acrylic ester polymer adhesive film, an epoxy resin adhesive film, a fullerene polyester adhesive film, a sulfur-containing resin adhesive film, a silicon resin adhesive film, a polyurethane adhesive film, a polycarbonate adhesive film, a cyclic olefin copolymer adhesive film and a polyphosphazene resin adhesive film, preferably the acrylic ester polymer adhesive film comprises one or more of a polymethyl methacrylate resin adhesive film, a polyacrylate resin adhesive film, a polyurethane resin adhesive film, an epoxy acrylate double ester resin adhesive film and a polyphenyl methacrylate adhesive film, and preferably the sulfur-containing resin adhesive film comprises one or more of a thiophene resin adhesive film, a fluorenyl modified polyphenylene sulfide adhesive film and polyphenylene sulfide.

In order to provide the packaging adhesive film with a high refractive index and a better packaging performance, the thickness of the packaging adhesive film is preferably 0.1-1 mm, preferably 0.4-0.5 mm, the thickness of the first adhesive film substrate 10 is preferably 350-500 μm, and the thickness of the organic high refractive index portion 20 is preferably 50-200 μm. When the organic high-refraction-rate part 20 is embedded in the groove of the first adhesive film substrate 10, the thickness of the organic high-refraction-rate part 20 includes the thickness of the part in the groove of the first adhesive film substrate 10.

The organic high-refraction-rate part 20 can adopt a gradual-change refractive index design to further improve the light conversion rate of the packaging adhesive film. The refractive index of the organic high-refractive-index portion 20 is preferably 1.5 to 1.65, and the refractive index of the organic high-refractive-index portion 20 is preferably gradually increased in a direction away from the surface of the first adhesive film base 10, for example, by continuously printing an organic high-refractive-index material in which the concentration of the organic dopant having a high refractive index is gradually increased. In order to simplify the manufacturing process of the organic high-refractive-index portion 20 with gradually increasing refractive index, the organic high-refractive-index portion 20 is divided into a plurality of sub-layers and is respectively disposed, for example, the organic high-refractive-index portion 20 includes a plurality of organic high-refractive-index layers sequentially stacked on the surface of the first adhesive film base 10, the refractive index of each organic high-refractive-index layer increases sequentially along the direction away from the surface of the first adhesive film base 10, each organic high-refractive-index layer is manufactured by printing, pasting or ink-jet printing, and the refractive index difference is formed by adjusting the concentration of the organic dopants with high refractive index in each organic high-refractive-index layer or selecting the organic dopants with high refractive indexes with different refractive.

In order to effectively improve the light convergence effect of the variably designed organic high-refractive-index portion 20 under the condition of a simpler process, it is preferable that the organic high-refractive-index portion 20 includes two organic high-refractive-index layers, the refractive index of the organic high-refractive-index layer close to the first adhesive film substrate 10 is 1.5 to 1.70, the refractive index of the other organic high-refractive-index layer is 1.71 to 1.8, or the refractive index of the organic high-refractive-index layer close to the first adhesive film substrate 10 is 1.5 to 1.55, and the refractive index of the other organic high-refractive-index layer is 1.56 to 1.60. Those skilled in the art can use corresponding high refractive index materials or set corresponding concentrations, for example, a silk screen printing process is used to set a silica gel layer as the organic high refractive index portion in each groove, a methylphenyl vinyl silica gel layer with a thickness of 75 μm and a refractive index of 1.55 is printed in each groove, and then a silk screen printing process is used to set a phenyl vinyl silica gel layer with a thickness of 75 μm and a refractive index of 1.57 on the methylphenyl vinyl silica gel layer, so as to obtain the organic high refractive index portion 20 including two organic high refractive index layers.

In order to make more incident light incident on the cell and further improve the light utilization rate of the packaging adhesive film, as shown in fig. 3 and 4, preferably, a plurality of grooves are formed on one surface of the first adhesive film substrate 10 at intervals, the organic high-refraction-rate portion 20 is embedded in the grooves, the packaging adhesive film further includes a reflection portion 30, the reflection portion 30 and the organic high-refraction-rate portion 20 are disposed on the same surface of the first adhesive film substrate 10 and located at a gap between adjacent organic high-refraction-rate portions 20, as mentioned above, the organic high-refraction-rate portion 20 is disposed on one surface of the first adhesive film substrate 10 at intervals, and then the reflection portion 30 is located at the gap between the organic high-refraction-rate portions 20, and when packaged in the solar cell module, the reflection portion 30 and the cell gap are in one-to-one correspondence.

In some embodiments, it is preferable that the surface of the organic high-refraction-rate part 20 away from the first adhesive film base 10 and the surface of the reflection part 30 away from the first adhesive film base 10 are coplanar, so that the packaging process is easier to operate, the surface height difference of the packaging adhesive film is effectively avoided, and the cell is prevented from being fractured. The above-mentioned reflective part 30 can be disposed by referring to the conventional latticed adhesive film having the reflective part 30 in the prior art, preferably, the reflective part 30 includes a third adhesive film base and a reflective dopant, the third adhesive film base and the reflective dopant in this application can be selected from materials commonly used in the art, in order to make the reflective part 30, the first adhesive film base 10 and the organic high-refraction-rate part 20 cooperate with each other better to achieve a synergistic effect, the resin material forming the third adhesive film base preferably includes one or more of ethylene-vinyl acetate, ethylene-alpha-olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene-catalyzed polyethylene, the dopant in this application can be selected from dopants commonly used in the art to improve the reflectivity of the adhesive film, for example, the reflective dopant can be selected from hollow glass beads, metallocene-catalyzed polyethylene, or metallocene-catalyzed polyethylene, One or more of calcium carbonate, barium sulfate, talcum powder, titanium dioxide, zinc oxide, carbon black, graphene oxide, copper-chromium black, magnesium hydroxide, aluminum oxide, magnesium oxide, boron nitride, silicon carbide, ammonium phosphate, ammonium polyphosphate, pentaerythritol, dipentaerythritol, pentaerythritol ester and melamine polyphosphate borate. The reflectivity of the reflecting part 30 in the wavelength range of 400-700 nm is preferably not less than 92%, and the light utilization rate of the packaging adhesive film can be better improved by the reflecting part 30 in the reflectivity range.

The resin material forming the first adhesive film may be selected from resin materials commonly used in the art, and in order to provide stronger adhesion and compatibility between the adhesive film substrate and the cell, and improve the structural stability of the whole photovoltaic module, the resin material forming the first adhesive film substrate 10 preferably includes one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer, and metallocene-catalyzed ethylene-butylene copolymer.

In order to improve the overall performance of the adhesive film, in some embodiments, the first adhesive film base 10 includes 100 parts of a resin material, 0.01 to 3 parts of a cross-linking agent, 0.01 to 10 parts of an auxiliary cross-linking agent, 0 to 0.4 part of an ultraviolet absorber, 0 to 0.5 part of an antioxidant, 0 to 1.0 part of a light stabilizer, and 0 to 3.0 parts of a tackifier.

The cross-linking agent can promote cross-linking among molecules in the glue film matrix, so that the cross-linking degree is improved. The above-mentioned crosslinking agent can be selected from those commonly used in the art, and preferably, the above-mentioned crosslinking agent includes, but is not limited to, isopropyl t-butylperoxycarbonate, 2, 5-dimethyl-2, 5- (di-t-butylperoxy) hexane, 2-ethylhexyl t-butylperoxycarbonate, 1-bis (t-butylperoxy) -3,3, 5-trimethylcyclohexane, 1-bis (t-amylperoxy) cyclohexane, 1-bis (t-butylperoxy) cyclohexane, 2-bis (t-butylperoxy) butane, t-amyl peroxy-2-ethylhexylcarbonate, 2, 5-dimethyl-2, 5-bis (benzoylperoxy) -hexane, tert-amyl peroxycarbonate, tert-butyl peroxy3, 3, 5-trimethylhexanoate.

Such co-crosslinking agents include, but are not limited to, triallyl isocyanurate, triallyl cyanurate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, trimethylolpropane tetraacrylate, ditrimethylolpropane tetramethacrylate, propoxylated pentaerythritol tetraacrylate, 2,4, 6-tris (2-propenyloxy) -1,3, 5-triazine, tricyclodecane dimethanol diacrylate, triallyl cyanurate, trimethylolpropane triacrylate, ethoxylated glycerol triacrylate, propoxylated pentaerythritol tetraacrylate, trimethylolpropane triacrylate, trimethylolpropane tetraacrylate, 2,4, 6-tris (2-propenyloxy) -1,3, 5-triazine, one or more of the group consisting of propoxylated neopentyl glycol diacrylate, ethoxylated bisphenol A dimethacrylate, 2-butyl-2-ethyl-1, 3-propanediol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate and polyethylene glycol dimethacrylate.

In some preferred embodiments, the antioxidant is a hindered phenol-based compound and/or a phosphite-based compound. Compared with other antioxidants, the antioxidant has better stability and oxidation resistance. More preferably, the hindered phenol-based compound includes, but is not limited to, 2, 6-di-tert-butyl-4-ethylphenol, 2 ' -methylene-bis- (4-methyl-6-tert-butylphenol), 2 ' -methylene-bis- (4-ethyl-6-tert-butylphenol), 4 ' -butylidene-bis- (3-methyl-6-tert-butylphenol), octadecyl-3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate, pentaerythritol-tetrakis [3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate ], 7-octadecyl-3- (4 ' -hydroxy-3 ', one or more of the group consisting of 5 '-di-tert-butylphenyl) propionate, tetrakis- [ methylene-3- (3', 5 '-di-tert-butyl-4' -hydroxyphenyl) propionate ] methane; phosphite based compounds include, but are not limited to, one or more of the group consisting of tris (2, 4-di-t-butylphenyl) phosphite, bis [2, 4-bis (1, 1-dimethylethyl) -6-methylphenyl ] ethyl ester phosphite, tetrakis (2, 4-di-t-butylphenyl) [1, 1-biphenylyl ] -4, 4' -diyl bisphosphite, and bis (2, 4-di-t-butylphenyl) pentaerythritol diphosphite. By adding the antioxidant, the processing performance of the adhesive film matrix can be improved, the stability of the adhesive film matrix in a long-term and using process can be improved, and the degradation caused by the action of hot oxygen can be delayed.

The ultraviolet absorber added into the adhesive film substrate can absorb most of ultraviolet energy and convert the ultraviolet energy into heat, so that the electronic device is protected from being damaged by ultraviolet rays. In a preferred embodiment, the above-mentioned ultraviolet light absorbers include, but are not limited to, benzophenone and/or benzotriazole species, and more preferably, the ultraviolet light absorbers include, but are not limited to, one or more of the group consisting of 2-hydroxy-4-n-octoxybenzophenone, 2-tetramethylene bis (3, 1-benzoxazin-4-one), 2- (2 ' -hydroxy-5-methylphenyl) benzotriazole, 2 ' -dihydroxy-4, 4 ' -dimethoxybenzophenone.

The addition of the light stabilizer can improve the stability of the adhesive film matrix under long-term ultraviolet radiation. Preferably, the light stabilizer is a hindered amine-based compound. In some preferred embodiments, the light stabilizer includes, but is not limited to, bis (2,2,6, 6-tetramethyl-4-piperidyl) sebacate, bis (1-octyloxy-2, 2,6, 6-tetramethyl-4-piperidyl) sebacate, graft copolymers obtained by polymerizing 4- (meth) acryloyloxy-2, 2,6, 6-tetramethylpiperidine with an alpha-olefinic monomer, 4-hydroxy-2, 2,6, 6-tetramethyl-1-piperidinol, 3, 5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester, sebacic acid bis-2, 2,6, 6-tetramethylpiperidinol and tris (1,2,2,6, 6-pentamethyl-4-piperidyl) phosphite.

In some preferred embodiments, the adhesion promoter includes, but is not limited to, one or more of the group consisting of gamma-aminopropyltriethoxysilane, gamma-methacryloxypropyltrimethoxysilane, gamma- (2, 3-glycidoxy) propyltrimethoxysilane, vinyltrimethoxysilane, N- (beta-aminoethyl) -gamma-aminopropyltrimethoxysilane, gamma-glycidoxypropyltrimethylsilane, 3-aminopropyltrimethylsilane. By adding the tackifier, the viscosity of the adhesive film matrix can be effectively improved.

In a preferred embodiment, the corrosion inhibitor refers to a substance capable of absorbing free acid in the adhesive film, including but not limited to metal oxides, metal hydroxides, and metal carbonates. The corrosion inhibitor includes, but is not limited to, one or more of the group consisting of magnesium hydroxide, calcium hydroxide, zinc hydroxide, barium hydroxide, aluminum hydroxide, magnesium oxide, calcium oxide, zinc oxide, barium oxide, aluminum oxide, magnesium carbonate, calcium carbonate, zinc carbonate, barium carbonate, hydrotalcite, and the like. The corrosion resistance of the adhesive film base body can be improved by adding the corrosion inhibitor.

In another exemplary embodiment of the present application, a photovoltaic module is provided, which includes a glass cover plate, a front layer encapsulant film, a solar cell unit, a back layer encapsulant film, and a back layer cover plate, wherein the front layer encapsulant film and/or the back layer encapsulant film is any one of the foregoing encapsulant films, and the organic high-refraction-index portions 20 are disposed in one-to-one correspondence with the solar cells in the solar cell unit. The utility model provides a packaging adhesive film refracting index is high, stable in structure, can effectively reduce the light loss that reflection and diffuse reflection light caused, makes photovoltaic module's light utilization ratio obtain effectual promotion. And only the organic high-refraction-rate part 20 is arranged on the surface of the packaging adhesive film corresponding to the battery piece, so that the refraction rate of the packaging adhesive film is improved, the consumption of expensive organic high-refraction-rate part 20 materials is effectively reduced, and the cost is saved.

The advantageous effects of the present application will be further described below with reference to examples and comparative examples.

Example 1

The packaging adhesive film of the embodiment includes a first adhesive film substrate and an organic high-refractive-index portion, wherein the first adhesive film substrate is an EVA (VA content is 28 wt%, du pont, usa, refractive index is 1.48, and EVA used in the following embodiments is the same as that of embodiment 1) layer.

1) And (3) extruding and tape-casting the first adhesive film base layer (with the thickness of 400 mu m), and arranging fixed patterns in an array arrangement on the surface of the first adhesive film base layer by using a pattern roller, wherein the fixed patterns correspond to the size (156mm) of the battery piece, so that the area of the first adhesive film base layer corresponding to the battery piece is a groove, and the depth of the groove is 50 mu m.

2) A methyl phenyl vinyl silica gel layer (with a refractive index of 1.55 as an organic high-refractive-index part) is arranged in each groove by adopting a spraying process, and the thickness of the sprayed organic high-refractive-index part is 50 micrometers.

Example 2

The packaging adhesive film of the embodiment comprises a first adhesive film substrate, a reflecting part and an organic high-refraction-rate part, wherein the first adhesive film substrate is an EVA (ethylene vinyl acetate) layer.

1) And (3) extruding and tape-casting the first adhesive film base layer (with the thickness of 400 mu m), arranging fixed patterns in an array arrangement on the surface of the first adhesive film base layer by using a pattern roller, and enabling the area of the first adhesive film base layer corresponding to the battery piece to be a groove with the depth of 100 mu m corresponding to the size (156mm) of the battery piece.

2) A silica gel layer (refractive index of 1.58, as an organic high-refractive-index portion) containing trimethylolpropane triacrylate (20 wt.%), epoxidized silica gel (KH560, 30 wt.%), 1-hydroxycyclohexyl phenyl ketone (5 wt.%) and ethanol (45 wt.%) was placed in each groove by a spray coating process, and then cured by ultraviolet irradiation, resulting in an organic high-refractive-index portion having a thickness of 150 μm.

3) The screen printing process is adopted to print the mixture of the EVA resin and the titanium dioxide (weight ratio: 100:5) is arranged at the position corresponding to the cell gap (as a reflecting part), the thickness is 50 μm, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is 92%.

Example 3

The encapsulation adhesive film of the embodiment includes a first adhesive film base, a reflection portion and an organic high-refraction-rate portion, where the first adhesive film base is a POE (tao usa, No. 8450, refractive index is 1.49, and POE used in the following embodiments is the same as EVA of embodiment 1) layer.

2) A methyl phenyl vinyl silica gel layer (as an organic high-refractive-index part) is arranged in each groove by adopting a screen printing process, the methyl phenyl vinyl silica gel layer with the thickness of 75 microns and the refractive index of 1.55 is printed in the groove, and then the phenyl vinyl silica gel layer with the thickness of 75 microns and the refractive index of 1.57 is arranged on the methyl phenyl vinyl silica gel layer by adopting the screen printing process.

3) Adopting an ink-jet printing process to mix POE resin and titanium dioxide (weight ratio: 100:5) is arranged at the position corresponding to the cell gap (as a reflecting part), the thickness is 50 μm, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is 92.5%.

Example 4

The encapsulation glued membrane of this embodiment includes first glued membrane base member, reflection part and organic matter high refractive index portion, and first glued membrane base member is the POE layer.

1) And (3) extruding and tape-casting the first adhesive film base layer (with the thickness of 400 mu m), arranging fixed patterns in an array arrangement on the surface of the first adhesive film base layer by using a pattern roller, and enabling the area of the first adhesive film base layer corresponding to the battery piece to be a groove with the depth of 120 mu m corresponding to the size (156mm) of the battery piece.

2) A silica gel layer (as an organic high-refractive-index portion) was placed in each groove by a screen printing process, and a methylphenyl vinyl silica gel layer having a thickness of 50 μm and a refractive index of 1.55 was printed in the groove. And then a phenyl vinyl silica gel layer with the thickness of 50 mu m and the refractive index of 1.57 is arranged on the methyl phenyl vinyl silica gel layer by adopting a screen printing process. And finally, arranging a phenyl hydrogen-containing silica gel layer with the thickness of 50 mu m and the refractive index of 1.62 on the phenyl vinyl silica gel layer by adopting a screen printing process.

3) The screen printing process is adopted to print the mixture of the EVA resin and the titanium dioxide (weight ratio: 100:5) is arranged at the position corresponding to the cell gap (as a reflecting part), the thickness is 30 μm, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is 92.1%.

Example 5

The packaging adhesive film of the embodiment comprises a first adhesive film substrate and an organic high-refraction-rate part, wherein the first adhesive film substrate is an EVA (ethylene vinyl acetate) layer.

1) And (3) extruding and tape-casting the first adhesive film base layer (with the thickness of 500 mu m), arranging fixed patterns in an array arrangement on the surface of the first adhesive film base layer by using a pattern roller, and enabling the area of the first adhesive film base layer corresponding to the battery piece to be a groove with the depth of 200 mu m corresponding to the size (156mm) of the battery piece.

2) A mixture (5N, serving as an organic high-refraction-rate part) of EVA resin and polymethyl methacrylate is arranged in each groove by adopting a spraying process, wherein the weight ratio of the EVA resin to the polymethyl methacrylate is 100:5, the particle size of the polymethyl methacrylate is 50 mu m, the refractive index is 1.492, the refractive index of the organic high-refraction-rate part is 1.49, and the thickness of the printed organic high-refraction part is 200 mu m.

Example 6

2) A mixture of EVA resin and cyclic olefin copolymer (APL 6905T, as an organic high-refraction-rate part) is arranged in each groove by adopting a spraying process, wherein the weight ratio of the EVA resin to the cyclic olefin copolymer is 100:5, the particle size of the cyclic olefin copolymer is 50 mu m, the refractive index is 1.53, the refractive index of the organic high-refraction-rate part is 1.521, and the thickness of the printed organic high-refraction part is 200 mu m.

Example 7

The packaging adhesive film of the embodiment includes a first adhesive film substrate, a reflection portion and an organic high-refraction rate portion, wherein the first adhesive film substrate is an EVA (VA content of 28 wt%, du pont usa) layer.

1) And (3) extruding and tape-casting the first adhesive film base layer (with the thickness of 450 mu m), and arranging fixed patterns in an array arrangement on the surface of the first adhesive film base layer by using a pattern roller, wherein the fixed patterns correspond to the size (156mm) of the battery piece, so that the area of the first adhesive film base layer corresponding to the battery piece is a groove, and the depth of the groove is 150 mu m.

2) A screen printing process is adopted to arrange a mixture (as an organic high-refraction-rate part) of EVA resin and epoxy acrylate diester resin in each groove, wherein the weight ratio of the EVA resin to the epoxy acrylate diester resin is 100:1, the particle size of the epoxy acrylate diester resin is 60 mu m, the refractive index is 1.584, the refractive index of the organic high-refraction-rate part is 1.578, and the thickness of the printed organic high-refraction part is 200 mu m.

3) The screen printing process is adopted to print the mixture of the EVA resin and the titanium dioxide (weight ratio: 100:10) is arranged at the position corresponding to the cell gap (as a reflecting part), the thickness is 50 μm, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is 93.1%.

Example 8

1) And (3) extruding and tape-casting the first adhesive film base layer (with the thickness of 350 mu m), arranging fixed patterns in an array arrangement on the surface of the first adhesive film base layer by using a pattern roller, and enabling the area of the first adhesive film base layer corresponding to the battery piece to be a groove with the depth of 100 mu m corresponding to the size (156mm) of the battery piece.

2) And arranging the organic high-refraction-rate parts in the grooves by adopting a screen printing process, wherein the organic high-refraction-rate parts comprise two organic high-refraction-rate layers. A cycloolefin copolymer layer (APL 6905T, mitsui chemical) having a thickness of 75 μm and a refractive index of 1.53 was printed in the grooves, and a polycarbonate layer (PC 1100, museum chemical) having a thickness of 75 μm and a refractive index of 1.586 was provided on the cycloolefin copolymer layer by a screen printing process.

3) The mixture of POE resin and titanium dioxide powder (weight ratio: 100:10) is arranged at the position corresponding to the cell gap (as a reflecting part), the thickness is 50 μm, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is 93.0%.

Example 9

2) And arranging the organic high-refraction-rate part in each groove by adopting a screen printing process, wherein the organic high-refraction-rate part comprises three organic high-refraction-rate layers. A layer of a cycloolefin copolymer (APL 6905T, mitsui chemical) having a thickness of 50 μm and a refractive index of 1.53 was first printed in the recesses. A polycarbonate layer (Letian chemical, PC1100) having a thickness of 50 μm and a refractive index of 1.586 was formed on the cycloolefin copolymer layer by a screen printing process. Finally, an epoxy resin layer (china petrochemical, E44) having a thickness of 50 μm and a refractive index of 1.65 was disposed on the polycarbonate layer by a screen printing process.

3) The mixture of POE resin and titanium dioxide powder (weight ratio: 100:10) is arranged at the position corresponding to the cell gap (as a reflecting part), the thickness is 30 μm, and the reflectivity of the reflecting part in the wavelength range of 400-700 nm is 93.1%.

Example 10

The difference from example 7 is that the particle size of the epoxyacrylic diester resin is 20 μm.

Example 11

The difference from example 7 is that the particle size of the epoxy acrylic diester resin is 40 μm.

Example 12

The difference from example 7 is that the particle size of the epoxyacrylic diester resin is 140 μm.

Example 13

The difference from example 7 is that the particle size of the epoxyacrylic diester resin is 100 μm.

Example 14

The difference from the embodiment 6 is that,

in the step 1), the thickness of the first adhesive film base body layer is 100 micrometers, and the thickness of the groove on the first adhesive film base body is 50 micrometers;

the particle size of the cycloolefin copolymer in the step 2) was 20 μm, the refractive index of the organic high refractive index portion was 1.55, and the thickness of the printed organic high refractive index portion was 50 μm.

Example 15

The difference from the embodiment 6 is that,

in the step 1), the thickness of the first adhesive film base body layer is 1000 microns, and the thickness of the groove on the first adhesive film base body is 400 microns;

the thickness of the organic high-refraction part printed in the step 2) is 400 μm.

Comparative example 1

EVA (VA content is 28 wt%, DuPont, USA) resin and nano zinc sulfide (particle size: 20nm, refractive index is 2.3) powder are extruded and cast, the thickness of the packaging adhesive film is 450 μm, and the refractive index is 1.518.

And (3) laminating the adhesive films of the examples and the comparative examples, and then testing the light transmittance, wherein the refractive index is tested by adopting an Abbe refractometer, the light transmittance is tested according to GB/T2410-2008, and the light transmittance of the adhesive film of 400-700 nm is tested by using an ultraviolet-visible spectrophotometer.

Test item and test method

1. Adhesive force

The packaging adhesive films obtained in the examples and the comparative examples are sequentially stacked according to a glass/packaging adhesive film (two layers)/flexible back plate of 300mm multiplied by 150mm and placed in a vacuum laminating machine, and the pressing is carried out according to a laminating process of 150 ℃ for 18 minutes to prepare a pressing piece.

The flexible backsheet/encapsulant film was cut into 10mm ± 0.5mm test pieces every 5mm in the width direction for testing the adhesion between the encapsulant film and the glass. According to the test method of GB/T2790-1995, the peeling force between the packaging adhesive film and the glass is tested on a tensile testing machine at a tensile speed of 100mm/min +/-10 mm/min, and the arithmetic mean value of the three tests is taken to be accurate to 0.1N/cm.

2. Refractive index

The packaging adhesive films obtained in the examples and the comparative examples are put into a vacuum laminating machine according to the sequence of the release film/the packaging adhesive film/the release film, and are laminated and cured for 15 minutes at 150 ℃. And taking out the laminated packaging adhesive film for testing. And measuring the refractive index of the packaging adhesive film by using an Abbe refractometer.

3. Yellowing test

The packaging adhesive films obtained in the above examples and comparative examples are put into an ultraviolet aging test box according to a sample with a glass/packaging adhesive film/backboard structure, and ultraviolet radiation is carried out on the glass/packaging adhesive film/backboard structure to 120kWh/m²And (6) sampling. Before and after the experiment, the yellow index of the test sample is tested according to ASTM E313-2010, each test sample is tested to be not less than 3 points, the average value is taken, and the difference value of the yellow indexes before and after the ultraviolet accelerated aging test is taken as the yellow index delta YI.

4. Evaluation of laminate appearance of Components

The solar cell modules were packaged by the same process using the packaging adhesive films obtained in the above examples and comparative examples. And laminating according to the laminating sequence of glass/packaging adhesive film/battery piece/packaging adhesive film/glass, and laminating according to the laminating process of the adhesion test to manufacture a standard double-glass solar battery assembly, wherein the specification of the assembly is a model of 60 (6 multiplied by 10) battery pieces (the battery pieces are of the same manufacturer, the same batch, the same grade and the size of 156 mm). And manufacturing assemblies according to different packaging adhesive films for appearance evaluation. The evaluation standard takes the occurrence of bubbles, impurities and delamination between a packaging adhesive film and a battery piece or glass as judgment objects, and specifically comprises the following steps:

o: no Δ: slight x: severe.

5. Testing the power of the component:

use of the above-produced component module in 1000w/m²Power was measured with a quickkun 820A power simulator at nominal irradiance and ambient temperature of 30 ℃.

The evaluation results are shown in table 1 below.

The test results are shown in table 1.

TABLE 1

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:

this application sets up the material that the refracting index is higher (1.49 ~ 1.8) (organic matter high refraction rate portion promptly) on a surface of first glued membrane base member, when making photovoltaic module, the encapsulation glued membrane is provided with the face of organic matter high refraction rate portion 20 and faces towards photovoltaic cell to match the refracting index of battery piece better, make the refraction angle of incident light diminish, reduce the light loss that reflection and diffuse reflection light caused simultaneously, effectively promoted light utilization ratio. Simultaneously, because the organic matter high refractive index portion of the encapsulation glued membrane of this application sets up on the surface of first glued membrane base member, this structure is more stable, can not appear the problem that the refracting index that leads to because of the additive reunion among the prior art can't effectively improve. To sum up, the encapsulation glued membrane of this application, stable in structure can effectively promote the refracting index, and then improves the light conversion rate by its photovoltaic module who constitutes. And the material forming the organic matter high-refraction rate part is usually higher in price, so that the organic matter high-refraction rate part can be arranged only at the position, corresponding to the battery piece, on the packaging adhesive film, so that the requirement of improving the refractive index of the packaging adhesive film is met, the coverage area of the organic matter high-refraction rate part is reduced, and the cost is saved.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A packaging adhesive film, comprising: the solar cell comprises a first adhesive film base body (10) and a plurality of organic matter high-refraction-rate parts (20), wherein the organic matter high-refraction-rate parts (20) are arranged on one surface of the first adhesive film base body (10) at intervals, the organic matter high-refraction-rate parts (20) are arranged in one-to-one correspondence with packaged solar cells, the refraction rate of the first adhesive film base body (10) is 1.45-1.50, the refraction rate of the organic matter high-refraction-rate parts (20) is 1.49-1.8, and the refraction rate of the organic matter high-refraction-rate parts is higher than that of the first adhesive film base body.

2. The packaging adhesive film according to claim 1, wherein a plurality of grooves are formed on one surface of the first adhesive film substrate (10) at intervals, the organic high-refraction-rate portion (20) is embedded in the grooves, and preferably, the thickness of the organic high-refraction-rate portion (20) is the same as the depth of the grooves.

3. The adhesive packaging film according to claim 1 or 2, wherein the organic high-refraction-index portion (20) is a composite layer of one or more of a (meth) acrylate layer, an epoxy layer, and a silicone layer,

preferably, the silica gel layer is selected from one or more of an epoxidized silica gel layer, an acrylated silica gel layer, a methyl phenyl vinyl silica gel layer, a phenyl hydrogen-containing silica gel layer, a phenyl vinyl silica gel layer and a hydroxyl-terminated methyl vinyl silica gel layer, and the refractive index of the silica gel layer is preferably 1.55-1.65;

when the organic high-refractive-index portion (20) is preferably a (meth) acrylate layer or an epoxy layer, the raw material forming the organic high-refractive-index portion (20) preferably includes a monomer and a photoinitiator, the monomer is one or two of a (meth) acrylate monomer and an epoxy monomer, the (meth) acrylate monomer is preferably one or more selected from pentaerythritol tetraacrylate, tris [2- (acryloyloxy) ethyl ] isocyanurate, trimethylolpropane triacrylate, dipentaerythritol hexaacrylate, tricyclodecane dimethanol diacrylate and tris (2-hydroxyethyl) isocyanurate diacrylate, and the epoxy monomer is preferably selected from trimethylolpropane triglycidyl ether, pentaerythritol triglycidyl ether, glycerol triglycidyl ether, triglycidyl isocyanurate, and the like, One or more of triglycidyl cyanurate, triglycidyl hydantoin, pentaerythritol tetraglycidyl ether and dipentaerythritol tetraglycidyl ether and tetraglycidyl benzylethane.

4. The packaging adhesive film according to claim 1 or 2, wherein the organic high-refraction-index portion (20) is a high-refraction-index adhesive film with a refractive index of 1.5-1.8, the high-refraction-index adhesive film comprises a second adhesive film substrate and a high-refraction-index organic dopant, the refractive index of the high-refraction-index organic dopant is 1.52-2.10, preferably 1.52-1.65,

preferably, the high-refractive-index organic dopant is selected from one or more of acrylate polymers, epoxy resins, fullerene polyesters, sulfur-containing resins, silicone resins, polyurethanes, polycarbonates, cyclic olefin copolymers and polyphosphazenes, preferably, the acrylate polymers comprise one or more of polymethyl methacrylate resins, polyacrylate resins, polyurethane resins, epoxy acrylate diester resins and polyphenyl methacrylates, preferably, the sulfur-containing resins comprise one or more of thiophene resins, fluorenyl-modified polyphenylene sulfides and poly-p-phenylene sulfides, preferably, in the high-refractive-index adhesive film, the mass content of the high-refractive-index organic dopant is 0.1-10%, preferably, the particle size of the high-refractive-index organic dopant is 20-100 μm, more preferably 40-100 μm, and further preferably 60-100 μm,

the resin material for forming the second adhesive film base body preferably comprises one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene catalyzed ethylene-butylene copolymer, the second adhesive film base body preferably further comprises one or more of cross-linking agent, assistant cross-linking agent, antioxidant, ultraviolet absorbent, light stabilizer, tackifier, anti-corrosion agent and pigment, and the high-refractive-index adhesive film is preferably arranged on the first adhesive film base body (10) in a spraying, printing, pasting or ink-jet printing mode.

5. The packaging adhesive film according to claim 1 or 2, wherein the organic high-refraction-index portion (20) is a high-refraction-index adhesive film with a refraction index of 1.52-2.10, preferably a high-refraction-index adhesive film with a refraction index of 1.52-1.65, the high-refraction-index adhesive film is selected from one or more of an acrylate polymer adhesive film, an epoxy resin adhesive film, a fullerene polyester adhesive film, a sulfur-containing resin adhesive film, a silicone resin adhesive film, a polyurethane adhesive film, a polycarbonate adhesive film, a cyclic olefin copolymer adhesive film and a polyphosphazene resin adhesive film, preferably the acrylate polymer adhesive film comprises one or more of a polymethyl methacrylate resin adhesive film, a polyacrylate resin adhesive film, a polyurethane resin adhesive film, a epoxy acrylate resin adhesive film and a polyphenyl methacrylate adhesive film, preferably the sulfur-containing resin adhesive film comprises a thiophene resin adhesive film, One or more of fluorenyl modified polyphenylene sulfide glue film and polyphenylene sulfide glue film.

6. The packaging adhesive film according to claim 1 or 2, wherein the thickness of the packaging adhesive film is 0.1-1 mm, preferably 0.4-0.5 mm, preferably the thickness of the first adhesive film substrate (10) is 350-500 μm, and the thickness of the organic high-refraction rate portion (20) is 50-200 μm.

7. The packaging adhesive film according to any one of claims 1 to 6, wherein the refractive index of the organic high refractive index portion (20) is 1.51 to 1.65, preferably the refractive index of the organic high refractive index portion (20) gradually increases in a direction away from the surface of the first adhesive film base (10), preferably the organic high refractive index portion (20) comprises a plurality of organic high refractive index layers sequentially stacked on the surface of the first adhesive film base (10), and the refractive index of each organic high refractive index layer sequentially increases in a direction away from the surface of the first adhesive film base (10).

8. The packaging adhesive film according to any one of claims 1 to 7, wherein a plurality of grooves are formed in one surface of the first adhesive film substrate (10) at intervals, the organic high-refraction-rate portion (20) is embedded in the grooves, the packaging adhesive film further comprises a reflection portion (30), the reflection portion (30) and the organic high-refraction-rate portion (20) are disposed on the same surface of the first adhesive film substrate (10) and located at a gap between adjacent organic high-refraction-rate portions (20), preferably, the surface of the organic high-refraction-rate portion (20) far away from the first adhesive film substrate (10) is coplanar with the surface of the reflection portion (30) far away from the first adhesive film substrate (10), preferably, the reflection portion (30) comprises a third adhesive film substrate and a reflective dopant, preferably, the resin material forming the third adhesive film substrate comprises ethylene-vinyl acetate, and ethylene-vinyl acetate, One or more of ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene catalyzed polyethylene, preferably, the reflective dopant is selected from one or more of hollow glass beads, calcium carbonate, barium sulfate, talcum powder, titanium dioxide, zinc oxide, carbon black, graphene oxide, copper chromium black, magnesium hydroxide, aluminum oxide, magnesium oxide, boron nitride, silicon carbide, ammonium phosphate, ammonium polyphosphate, pentaerythritol, dipentaerythritol, polypentaerythritol ester and melamine polyphosphate borate, preferably, the reflectivity of the reflective part (30) in the wavelength range of 400-700 nm is more than or equal to 80%, and further preferably, the reflectivity of the reflective part (30) in the wavelength range of 400-700 nm is more than or equal to 90%.

9. The packaging adhesive film according to claim 1, wherein the resin material forming the first adhesive film substrate (10) comprises one or more of ethylene-vinyl acetate, ethylene-alpha olefin copolymer, ethylene-methyl methacrylate copolymer, ethylene-methacrylic acid ionomer and metallocene-catalyzed polyethylene, and preferably, the material forming the first adhesive film substrate (10) comprises 100 parts by weight of the resin material, 0.01 to 3 parts by weight of cross-linking agent, 0.01 to 10 parts by weight of co-cross-linking agent, 0 to 0.4 part by weight of ultraviolet light absorber, 0 to 0.5 part by weight of antioxidant, 0 to 1.0 part by weight of light stabilizer and 0 to 3.0 parts by weight of tackifier.

10. A photovoltaic module, comprising a glass cover plate, a front layer packaging adhesive film, a solar cell unit, a back layer packaging adhesive film and a back layer cover plate, wherein the front layer packaging adhesive film and/or the back layer packaging adhesive film is the packaging adhesive film of any one of claims 1 to 9, and the organic high-refraction-rate part (20) is arranged in one-to-one correspondence with the solar cells in the solar cell unit.