JP2000091610A - Solar cell cover film, method of manufacturing the same, and solar cell module using the cover film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cover film of a solar cell excellent in performance and productivity, capable of saving resources and reducing costs, a method of manufacturing the same, and a solar cell module using the same. SOLUTION: A solar cell filler layer 2 is laminated on a front cover film 1 and a solar cell filler layer 2 'is laminated on a back cover film 3 in advance to form a front or rear solar cell. The cover films 10 and 20 are produced. Then, a solar cell cover film 10 for a front surface is disposed on the front surface of the solar cell element 4, and a solar cell cover film 20 for a rear surface is disposed and laminated on the rear surface to manufacture the solar cell module 100. I do. Although various thermoplastic resins can be used for the filler layers 2 and 2 ', it is preferable to use a resin mainly containing an ethylene-vinyl acetate copolymer containing a crosslinking agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cover film used on the front or back of a solar cell and a method of manufacturing the same.
And regarding the solar cell module using the cover film, more specifically, the material of the cover film, the configuration, and by improving the manufacturing method, without impairing the performance of the solar cell, improvement of its productivity, and, The present invention relates to a solar cell cover film and a method for manufacturing the same, which enable resource saving and cost reduction, and a solar cell module using the cover film.

[0002]

2. Description of the Related Art Conventionally, in the production of a solar cell, for example, a heat-fusible filler sheet is laminated on both sides of a solar cell element, a front cover sheet is further disposed on a front side, and a rear cover sheet is disposed on the front side. A method has been adopted in which a back cover sheet is stacked on the side and exhausted and heated and pressurized by a vacuum laminating method such as a single vacuum method or a double vacuum method.

[0003] In particular, a glass plate is often used as a material for the front cover sheet from the viewpoints of transparency, moisture resistance, weather resistance, rigidity and the like. But,
The glass plate is excellent in the above-mentioned performance, but is inferior in trimming and other workability and handleability, so that a change to a plastic material is being promoted. However, when using a plastic sheet for the cover sheet, it was necessary to increase the thickness in order to obtain the required rigidity. In addition, the heat-fusible filler sheet also has a low rigidity. For this reason, a thick sheet is used in order to improve the handleability at the time of lamination and the exhaustability between layers.

[0004]

However, when a solar cell was manufactured by the above-described manufacturing method, good performance was obtained. However, the members at the time of lamination were a solar cell element and both sides were filled. Such as sheet material, front cover sheet and back cover sheet, which are complicated and require many steps, such as laminating and laminating them at predetermined positions, resulting in poor productivity. In addition, there is a problem in that the thickness of the back cover sheet is wasteful and the cost is high. The present invention has been made in order to solve such a problem, and an object thereof is to reduce the number of members when manufacturing a solar cell module by stacking each member of a solar cell. The process is simplified, and the filler layer and the thickness of the front cover sheet and back cover sheet are made as thin as possible to save resources and reduce costs, and are excellent in performance, compactness, long-term reliability, and economy. An object of the present invention is to provide a solar cell cover film capable of producing a solar cell module, a method for manufacturing the same, and a solar cell module using the cover film.

[0005]

The above object can be attained by the present invention described below. That is, the invention according to claim 1 is characterized in that a solar cell filler layer mainly composed of a thermoplastic resin is laminated on a front cover film or a back cover film for a solar cell. Consisting of a cover film.

By employing such a configuration, the following operation and effect can be obtained. The cover film of the solar cell of the present invention can be produced by laminating the filler layer on a wide and long front cover film or a back cover film, so that productivity can be improved. In addition, since the solar cell filler layer is laminated on the front cover film or the back cover film in advance, when the solar cell element is laminated on the front or back surface of the solar cell element to produce a solar cell module, the number of members is reduced. ,
The process can be simplified. The cover film of the solar cell of the present invention is a laminated film obtained by laminating the filler layer for the solar cell on a front cover film or a back cover film for a solar cell. Thus, even though the individual thicknesses are the same, the rigidity of the laminated film increases. Therefore, there is almost no problem in handling properties and exhaustability when laminating on the front or back surface of the solar cell element, and the thickness of each layer of the laminated film can be reduced as long as its function is not impaired. It is possible to achieve resource saving and cost reduction. Then, when manufacturing a solar cell module, on the front surface of the solar cell element, a cover film of the front solar cell obtained by laminating the filler layer on the front cover film, and on the back surface of the solar cell element. A back cover film of the solar cell, in which the filler layer is laminated on a back cover film, is laminated so that each filler layer faces the solar cell element, and is evacuated and heated and pressed by a vacuum lamination method to be laminated. By doing so, the filler layers on both sides are in close contact with the solar cell element surface, and the filler layers of both cover films are thermally fused at the outer peripheral edge, so the solar cell element is The solar cell module can be manufactured by being sealed and fixed between the rear cover film.

According to a second aspect of the present invention, the front cover film is formed of a multilayer laminated film, and at least one of a fluororesin film and a weather-resistant film, and a vapor-deposited layer of an inorganic oxide as a barrier layer, or The cover film for a solar cell according to claim 1, comprising one of a composite layer of an inorganic oxide vapor deposition layer and an inorganic organic hybrid coat layer laminated thereon.

As the fluororesin film, for example, an ethylene-tetrafluoroethylene copolymer resin (hereinafter, ETFE resin) film, a polyvinyl fluoride (hereinafter, PVF) film and the like can be preferably used. As the water-resistant film, a highly weather-resistant biaxially stretched polyethylene terephthalate film (hereinafter, a highly weather-resistant PET film) or the like can be suitably used. All of these films have excellent weather resistance.

The barrier layer means a water vapor or other gas barrier layer. Since the barrier layer is used as a part of the structure of the front cover film, it has transparency as well as water vapor and other gas barrier properties (in the visible light region). Light transmission)
It is also necessary to have Therefore, when a vapor deposited layer of an inorganic oxide is used as the barrier layer, for example, a vapor deposited layer of aluminum oxide, silicon oxide, or the like can be suitably used. In the case where a composite layer of an inorganic oxide vapor deposition layer and an inorganic-organic hybrid coat layer laminated thereon is used as the barrier layer, the lower inorganic oxide vapor deposition layer may be formed of the aluminum oxide or silicon oxide. Etc. are formed by vapor deposition on a base film, and a coating solution of an inorganic-organic hybrid material composed of, for example, tetraethoxysilane and ethylene-vinyl alcohol copolymer is applied thereon, and dried to form a composite layer. Can be formed. In this case, the inorganic-organic hybrid coat layer acts as a protective layer for the underlying inorganic oxide vapor deposition layer, and has the effect of further improving the water vapor and other gas barrier properties.
The barrier layer may be formed on a fluororesin film or a weather-resistant film, but may be formed on another base film and laminated on a fluororesin film or a weather-resistant film. .

By adopting such a configuration, the front cover film has excellent weather resistance, water vapor and other gas barrier properties, and transparency (transmittance of light in the visible light range). In addition to the functions and effects of the invention described in claim 1, the cover film for the front surface is more excellent in the above performance.

The invention according to claim 3 is the solar cell cover film according to claim 1 or 2, wherein the front cover film has an ultraviolet shielding ability. In order to make the front cover film have an ultraviolet shielding ability, for example, an ultraviolet absorber may be kneaded during the formation of the front cover film and contained in the whole, or the front cover film may be multi-layered, The layer may contain an ultraviolet absorber. The ultraviolet absorber is not particularly limited as long as it does not block light in the visible light range, and can be appropriately selected from known organic or inorganic ultraviolet absorbers and used.

By adopting such a configuration, the deterioration of the front cover film itself due to ultraviolet rays can be prevented, and at the same time, the deterioration of the adhesive layer and the filler layer laminated on the inner surface side can be prevented. The weather resistance of the entire solar cell can be improved.

[0013] The invention described in claim 4 is the cover film for a solar cell according to any one of claims 1 to 3, wherein the thickness of the front cover film is 10 µm to 70 µm.

Conventionally, since the front cover film is used alone and laminated on the outermost layer of the solar cell module, it has a certain rigidity in terms of suitability for handling and lamination in addition to the originally required protection function. Required
A film having a thickness of at least about 75 μm was used. On the other hand, in the present invention, since the filler layer is laminated on the front cover film in advance and used, the thickness is increased and the suitability for handling is sufficient. Therefore, the thickness of the front cover film only needs to be able to perform the protection function, and it has become possible to make the thickness as thin as 10 μm to 70 μm. As a result, the effects of resource saving and cost reduction are obtained.

According to a fifth aspect of the present invention, the back cover film is formed of a multilayer laminated film, and at least a vapor deposited layer of an inorganic oxide as a barrier layer or a vapor deposited layer of an inorganic oxide is laminated thereon. Any one of a composite layer with an inorganic-organic hybrid coat layer and a laminated film including a light-reflective resin film, or at least a metal foil layer or a metal-deposited layer, and either a laminated film including a resin film. The cover film of the solar cell according to claim 1, wherein the cover film is formed.

By adopting such a configuration, even if a part of the light incident from the front side of the solar cell module is transmitted to the rear side of the solar cell element, the light can reduce the light reflectivity of the back cover film. Since the light is reflected by any one of the resin film layer, the metal foil layer, and the metal vapor deposition layer and re-enters the solar cell element, light use efficiency is improved, and photoelectric conversion efficiency can be improved. In addition, an inorganic oxide deposited layer as a barrier layer on the back cover film, or a composite layer of an inorganic oxide deposited layer and an inorganic-organic hybrid coat layer laminated thereon, or a metal foil layer or metal deposited Since the layer is included, the barrier properties of water vapor and other gases are improved, the deterioration of the solar cell element is prevented, and the solar cell module can be used for a long time.

According to a sixth aspect of the present invention, the thermoplastic resin has an ethylene-vinyl acetate copolymer containing a crosslinking agent as a main component and at least one of an ultraviolet absorber and a coupling agent. The cover film of a solar cell according to any one of claims 1 to 5, characterized by comprising:

By adopting such a constitution, the thermoplastic resin of the filler layer of the cover film is excellent in heat fluidity and heat adhesion, is less deteriorated by ultraviolet rays and the like, and is excellent in weather resistance. Accordingly, good suitability for embedding the solar cell element in the filler layer of the cover film, and excellent thermal adhesion and weather resistance can be imparted.

The invention according to claim 7 is characterized in that the ethylene-vinyl acetate copolymer has a vinyl acetate content of 15 to 4
The solar cell cover film according to any one of claims 1 to 6, wherein the content is 5% by weight.

By adopting such a configuration, the thermal fluidity and the thermal adhesiveness of the ethylene-vinyl acetate copolymer are further improved, so that the filler layer of the cover film is suitable for embedding in the solar cell element. Thermal adhesiveness can be further improved.

The invention according to claim 8 is the solar cell cover film according to any one of claims 1 to 7, wherein the thickness of the solar cell filler layer is 50 μm to 500 μm. It is.

In the solar cell cover film of the present invention,
As described above, the front cover film or the back cover film is preliminarily laminated with the solar cell filler layer, and therefore has a thickness and rigidity. When this filler layer is used alone. It can be thinner. Specifically, the thickness of the filler layer may be a thickness necessary for embedding suitability, and can be 50 μm to 500 μm. However, it is preferable to make it as thin as possible,
50 μm to 300 μm is more preferable. Also in this case, in the conventional manufacturing method using the filler layer as a single sheet, the filler sheet having a thickness of 500 μm to 600 μm was used.
And the effect of cost reduction can be obtained.

According to a ninth aspect of the present invention, there is provided a solar cell cover film comprising a solar cell front cover film or a back cover film, and a solar cell filler layer mainly composed of a thermoplastic resin laminated on the front cover film or the back cover film. A production method, wherein the front cover film or the back cover film, a filler layer for a solar cell containing a thermoplastic resin as a main component, a thermal lamination method, a dry lamination method, an extrusion lamination method, an extrusion coating method, a calendar coating method. And a method of manufacturing a cover film for a solar cell, wherein the film is laminated by any one of the methods.

In the above, the thermal lamination method, the dry lamination method, the extrusion lamination method, the extrusion coating method, and the calendar coating method are all known lamination methods, but will be briefly described. In the thermal lamination method, two films which are formed into a film in advance, in this case, a front cover film or a back cover film, and a film of a filler layer for a solar cell mainly containing a thermoplastic resin are laminated. This is a method in which heat bonding is performed by heating and pressing with a heating roll or the like.

In the dry lamination method, two films formed in a film shape in advance, that is, a front cover film or a back cover film, and a film of a filler layer for a solar cell mainly containing a thermoplastic resin are used. , 2
Using a liquid-curable polyurethane adhesive or the like, apply it to one of the films, for example, the laminated surface of the front cover film or the back cover film, remove the solvent component by hot-air drying, etc. Property), the other film, that is, the film of the solar cell filler layer is overlaid thereon and pressed, usually,
This is a method in which the adhesive is wound up in a roll form, stored at room temperature or a relatively low heating temperature, and the adhesive is cured over time and bonded.

In the extrusion lamination method, two films which have been formed into a film shape in advance, that is, a front cover film or a back cover film, and a film of a filler layer for a solar cell mainly containing a thermoplastic resin are used. ,
This is a method in which a heat-adhesive resin is melt-extruded into a film shape using a T-die or the like, pressed and bonded, cooled, and laminated.

In the extrusion coating method, a film formed in advance, in this case, a front cover film or a back cover film is used as a base material, and an anchor coat (a kind of primer coat) is applied to the laminated surface thereof as necessary.
This is a method in which a resin of a filler layer for a solar cell mainly composed of a thermoplastic resin is melt-extruded and coated in a film shape using a T-die or the like, and cooled and pressed by a chill roll to laminate.

In the calender coating method, for example, a thermoplastic resin, in this case, a resin of a filler layer for a solar cell mainly composed of a thermoplastic resin is heated by a calender to form a film, and at the same time, is formed into a front cover. This is a method in which a film or a back cover film is overlaid on a laminated surface, covered, pressed, cooled, and laminated. Also in this case, an anchor coat can be applied to the laminated surface of the front cover film or the back cover film as needed.

By employing such a manufacturing method, a filler layer for a solar cell containing a thermoplastic resin as a main component can be continuously laminated on a wide and long front cover film or a back cover film. In addition, a cover film for a solar cell can be manufactured with high productivity.

According to a tenth aspect of the present invention, there is provided a solar cell module wherein the cover film of the solar cell according to any one of the first to eighth aspects is used outside a solar cell element. It is.

By adopting such a configuration, the solar cell module comprises a solar cell cover film in which a solar cell filler layer is previously laminated on a front cover film on the outside of the solar cell element, that is, on the front side. And, on the back side, a cover film of a solar cell in which a solar cell filler layer is previously laminated on a back cover film.

Therefore, the number of members at the time of manufacturing the solar cell module is reduced, so that the manufacturing process can be simplified and the productivity can be improved. Further, as for the cover film of the solar cell, as described in the invention described in any one of claims 1 to 8, the front cover film or the back cover film, and the filler layer for the solar cell,
Each of them has excellent performance and can be reduced in thickness, so that a solar cell module using them also has excellent performance, resource saving and cost reduction. Can be.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a cover film for a solar cell and a solar cell module using the same according to the present invention will be described below. The cover film of the solar cell according to the present invention has, for example, a configuration as shown in FIGS. Further, a solar cell module manufactured using such a cover film is, for example, shown in FIG.
The configuration shown in FIG.

FIG. 1A shows the front of the solar cell, that is, FIG.
It is a schematic cross section which shows the structure of the cover film of the front solar cell used on the light incidence side, (b) shows the structure of the back solar cell cover film used on the back side of the solar cell. FIG. Fig. 1 (a)
In, the cover film 10 of the front solar cell is
This is a configuration in which a front cover film 1 and a solar cell filler layer 2 are laminated. Although not shown in the drawings, an adhesive layer such as an adhesive layer, a heat-adhesive resin layer, and an anchor coat layer may be provided between the two to improve the adhesiveness. The front cover film 1 includes at least one of a fluororesin film and a weather-resistant film, an inorganic oxide vapor-deposited layer, or an inorganic oxide vapor-deposited layer and an inorganic-organic hybrid coat layer laminated thereon. It is preferable to use a laminated film including any one of the composite layer and the composite layer.

In FIG. 1B, the cover film 20 of the back solar cell has a structure in which the back cover film 3 and the solar cell filler layer 2 'are laminated. Also in this case, though not shown in the figure, an adhesive layer such as an adhesive layer, a heat-adhesive resin layer, and an anchor coat layer is provided between the two to improve the adhesiveness. be able to. The back cover film 3 has, for example, a vapor-deposited layer of an inorganic oxide as a barrier layer in an intermediate layer,
And, a laminated film in which a resin film such as white coloring having light reflectivity is laminated on at least one surface, or
It is preferable to use a laminated film having a metal foil layer or a metal deposition layer as an intermediate layer, and resin films laminated on both sides. For the filler layers 2 and 2 ′ for the solar cell, a resin composition containing various thermoplastic resins as main components can be used. By adjusting the vinyl content and the like, the thermal fluidity and thermal adhesiveness can be easily adjusted, so that it can be suitably used.

In FIG. 2, the solar cell module 100
Are a front cover film 1, a solar cell filler layer 2, a solar cell element 4,
The structure is such that a solar cell filler layer 2 ′ and a back cover film 3 are sequentially laminated.

Such a solar cell module 100 includes:
On the front side of the solar cell element 4, the cover film 10 of the front solar cell shown in FIG. 1A is disposed, and on the back side of the solar cell element 4, (b) of FIG. 2), the cover film 20 of the solar cell for the back side is disposed, and the cover film 20 is evacuated and heat-pressed by, for example, a vacuum laminating method, whereby the product can be manufactured with high productivity.

[0038]

The present invention will be described more specifically below with reference to examples and comparative examples. (Example 1) A front cover film having a thickness of 25
A laminate film was prepared by depositing aluminum oxide as a barrier layer on a ETFE resin film having a thickness of 300 μm to a thickness of 300 ° by a PVD method. In addition, as a filler layer for solar cells,
Ethylene-vinyl acetate copolymer (vinyl acetate content 25
%), 100 parts by weight of a crosslinking agent DCP (dicumyl peroxide), and 1 part by weight of an ultraviolet absorber (2,4-dihydroxybenzophenone) at 100 ° C. A film having a thickness of 200 μm was formed to prepare a film for a filler layer for a solar cell.
The film of the filler layer for a solar cell is overlaid on the aluminum oxide-deposited surface of the front cover film, and thermally bonded at 100 ° C. by a thermal lamination method to produce a cover film for a front solar cell of Example 1. did.

In order to manufacture a solar cell module using the front solar cell cover film, separately from the above, a solar cell element made of amorphous silicon, and a PVF as a rear solar cell cover film.
Film (thickness 25 μm), aluminum foil (thickness 20)
μm) and a PVF film (thickness: 25 μm) are sequentially laminated on one side of the laminated film by a dry lamination method, and further, the same film (thickness: 200 μm) as the filler layer film used for the front cover film is used. ) Are laminated by dry lamination method, and these are arranged from the outside in the order of the front solar cell cover film, the solar cell element, and the rear solar cell cover film, and vacuum laminated. The solar cell module of Example 1 was manufactured by stacking by the method.

Example 2 A 25 μm-thick PVF film containing an ultraviolet absorber as a front cover film, and aluminum oxide PVD as a barrier layer
Weatherproof P with a thickness of 12 μm deposited to a thickness of 200 mm
The ET film was bonded to the ET film by a dry lamination method using a polyurethane-based two-component curable adhesive so that the vapor-deposited surface was a laminated surface to produce a laminated film. In addition, an ethylene-vinyl acetate copolymer (vinyl acetate content: 40% by weight) is used as a resin of the filler layer for a solar cell.
100 parts by weight, 2 parts by weight of a cross-linking agent DCP, 5 parts by weight of a silane coupling agent, and 3 parts by weight of an ultraviolet absorber (2,4-dihydroxybenzophenone) are uniformly mixed at 95 ° C. to form a filler layer for a solar cell. Was prepared. Using the above-mentioned front cover film as a base material, its high weather resistance P
On the ET film side surface, the resin composition of the solar cell filler layer was coated and laminated to a thickness of 250 μm by a calendar coat method to prepare a front solar cell cover film of Example 2.

In order to manufacture a solar cell module using the front solar cell cover film, a solar cell element made of crystalline silicon and a PVF film as a rear solar cell cover film are separately provided. (Thickness 25 μm), aluminum foil (thickness 20 μm), PV
An F film (thickness: 25 μm) is sequentially laminated by dry lamination on one surface of the laminated film, and the same resin composition as that of the filler layer used for the front cover film is calender-coated. With a thickness of 250μ
and a laminated film prepared by coating and laminating m, and then arranging them from the outside in the order of a front solar cell cover film, a solar cell element, and a rear solar cell cover film, and laminating by a vacuum lamination method. Thus, a solar cell module of Example 2 was produced.

Example 3 A 25 μm thick PVF film containing an ultraviolet absorber was used as a front cover film, and silica was used as a barrier layer in a thickness of 40 μm by a CVD method.
A laminated film deposited at 0 ° was produced. Further, as a filler layer for a solar cell, 100 parts by weight of an ethylene-vinyl acetate copolymer (vinyl acetate content: 30% by weight), 1 part by weight of a crosslinking agent DCP, 5 parts by weight of a silane coupling agent, and an ultraviolet absorber (2 , 4-dihydroxybenzophenone) 1
Parts by weight were uniformly mixed at 85 ° C. to prepare a resin composition, and this was formed into a film having a thickness of 150 μm by a calendar method to prepare a film of a filler layer for a solar cell. The film of the solar cell filler layer was overlaid on the silica-deposited surface of the front cover film, and was thermally adhered at 90 ° C. by a thermal lamination method to produce a front solar cell cover film of Example 3. did.

In order to manufacture a solar cell module using the front solar cell cover film, separately from the above, a solar cell element made of amorphous silicon and a PVF film ( 25μm thick), aluminum foil (20μm thick)
m), a PVF film (thickness: 25 μm) is sequentially laminated on one side of the laminated film by a dry lamination method, and further, the same film (thickness: 150 μm) as the filler layer film used for the front cover film. ) Are laminated by dry lamination method, and these are arranged from the outside in the order of the front solar cell cover film, the solar cell element, and the rear solar cell cover film, and vacuum laminated. The solar cell module of Example 3 was produced by stacking in a manner.

(Example 4) As a front cover film, silica was vapor-deposited to a thickness of 200 mm by a CVD method as a barrier layer on a highly weatherable PET film having a thickness of 75 μm, and aluminum oxide was further deposited thereon by a PVD method. 200Å
To produce a laminated film. Further, as a filler layer for a solar cell, 100 parts by weight of an ethylene-vinyl acetate copolymer (vinyl acetate content: 35% by weight) and a crosslinking agent TB
1.5 parts by weight of PH [2,5-dimethyl-2,5-di (t-butylperoxy) hexane], 2 parts by weight of a crosslinking assistant TAC (triallyl cyanurate), 3 parts by weight of a silane coupling agent, ultraviolet rays 5 parts by weight of titanium oxide (particle size 0.03 μm) as an absorbent was uniformly mixed at 110 ° C. to prepare a resin composition, which was then calendered to a thickness of 10%.
It was formed into a film having a thickness of 0 μm to prepare a film of a filler layer for a solar cell. A film of the filler layer for a solar cell was overlaid on the silica and aluminum oxide deposition surface of the front cover film, and subjected to thermal lamination at 85 ° C.
To form a cover film of the front solar cell of Example 4.

In order to manufacture a solar cell module using the front solar cell cover film, separately from the above, a solar cell element made of amorphous silicon and a PVF film ( 25μm thick), aluminum foil (20μm thick)
m), a PVF film (thickness: 25 μm) is sequentially laminated on one side of the laminated film by a dry lamination method, and further, the same film (thickness: 100 μm) as the filler layer film used for the front cover film. ) Are laminated by dry lamination method, and these are arranged from the outside in the order of the front solar cell cover film, the solar cell element, and the rear solar cell cover film, and vacuum laminated. The solar cell module of Example 4 was produced by laminating in the manner described above.

Example 5 As a front cover film, a 25 μm-thick ETFE resin film was used as a barrier layer.
And a coating solution of an inorganic-organic hybrid material composed of 5 parts by weight of tetraethoxysilane and 95 parts by weight of an ethylene-vinyl alcohol copolymer was dried thereon by a gravure coating method at a coating amount of 1 g / m ² . The resultant was applied and dried to prepare a laminated film. Further, 100 parts by weight of an ethylene-vinyl acetate copolymer (vinyl acetate content 27% by weight) as a filler layer for a solar cell, and D as a crosslinking agent
A resin composition is prepared by uniformly mixing 3 parts by weight of CP, 2 parts by weight of a silane coupling agent, and 3 parts by weight of an ultraviolet absorber (2,4-dihydroxybenzophenone) at 105 ° C.
This was formed into a film having a thickness of 200 μm by a calendar method to prepare a film of a filler layer for a solar cell. The solar cell filler layer film was adhered to the inorganic organic hybrid coat layer surface of the front cover film by a dry lamination method using a polyurethane-based two-component curable adhesive to form a front solar cell of Example 5. A battery cover film was prepared.

In order to manufacture a solar cell module using the front solar cell cover film, a solar cell element made of crystalline silicon and a PVF film as a rear solar cell cover film are separately provided. (Thickness 25 μm), aluminum foil (thickness 20 μm), PV
F film (thickness 25 μm) is sequentially laminated on one side of a laminated film by a dry lamination method.
A laminated film in which the same film (thickness: 200 μm) as the film of the filler layer used for the front cover film is laminated by a dry lamination method, and these are coated from the outside from the front solar cell cover film , A solar cell element, and a cover film for the back side solar cell, and laminated by a vacuum lamination method to produce a solar cell module of Example 5.

Example 6 A 25 μm-thick PVF film containing an ultraviolet absorber was used as a front cover film, silica was used as a barrier layer by a CVD method to a thickness of 600 μm.
Then, a laminated film was formed by vapor deposition. Also, 100 parts by weight of ethylene-vinyl acetate copolymer (vinyl acetate content 30% by weight) as a filler layer for a solar cell, 1 part by weight of DCP as a crosslinking agent, and an ultraviolet absorber (2,4-dihydroxybenzophenone) 3 Parts by weight and uniformly mixed at 100 ° C. to prepare a resin composition, which was coated on the silica-deposited surface of the front cover film by an extrusion coating method.
Melt extrusion coating was performed so that the thickness became 150 μm, and the layers were laminated. Thus, a cover film of a front solar cell of Example 6 was produced.

In order to manufacture a solar cell module using the front solar cell cover film, a solar cell element made of amorphous silicon and a PVF film ( 25μm thick), aluminum foil (20μm thick)
m), a PVF film (thickness: 25 μm) is sequentially laminated on one surface of the laminated film by a dry lamination method, and further the same resin composition as the resin composition of the filler layer used for the front cover film is used. Similarly, a laminated film prepared by extrusion coating so as to have a thickness of 150 μm is prepared, and from the outside, a cover film for a front solar cell, a solar cell element, and a cover film for a rear solar cell are prepared. , And laminated by a vacuum lamination method to produce a solar cell module of Example 6.

Example 7 As a back cover film, a white PVF film (thickness: 38 μm), an aluminum foil (thickness: 50 μm), and a white PVF film (thickness: 38)
μm) in this order by a dry lamination method to produce a laminated film. In addition, as a solar cell filler layer used on the back side, that is, a solar cell filler layer laminated on the back cover film, an ethylene-vinyl acetate copolymer (vinyl acetate content 35% by weight) 100
Parts by weight, 2 parts by weight of a crosslinking agent DCP, 30 parts by weight of titanium oxide as a white pigment, and 2 parts by weight of an ultraviolet absorber (2,4-dihydroxybenzophenone) are uniformly mixed at 120 ° C. to prepare a resin composition. This was applied to one surface of the back cover film by extrusion coating to a thickness of 3
Melt extrusion coating so as to have a thickness of 00 μm and lamination,
A cover film (for the back surface) of the solar cell of Example 7 was produced.

In order to manufacture a solar cell module using the above-mentioned solar cell cover film for the back surface, a solar cell element made of amorphous silicon is separately provided,
As a cover film for the front solar cell, thickness 50μ
A PVA film containing an ultraviolet absorber of m, a laminated film obtained by vapor-depositing silica as a barrier layer to a thickness of 400 ° by a CVD method was used for the front cover film, and a silica-filled surface was formed of ethylene- Vinyl acetate copolymer (vinyl acetate content 30% by weight) 10
A resin composition obtained by uniformly mixing 0 parts by weight, 2 parts by weight of a crosslinking agent DCP, and 3 parts by weight of an ultraviolet absorber (2,4-dihydroxybenzophenone) at 100 ° C. has a thickness of 200 μm by extrusion coating. Prepare a laminated film and laminate these in order from the outside, the front solar cell cover film, the solar cell element, the rear solar cell cover film, and laminated by vacuum lamination method A solar cell module of Example 7 was produced.

(Comparative Example 1) A solar cell module was manufactured by a conventional manufacturing method, that is, a front cover film, a back cover film, a film of a filler layer for front and back surfaces, and a solar cell element were separately prepared as follows. Prepare and arrange these from the outside in the order of front cover film, film of the filler layer for the front, solar cell element, film of the filler layer for the back, back cover film,
Laminate by performing exhaust, heating and pressurization by vacuum lamination method,
A solar cell module of Comparative Example 1 was manufactured.

The front cover film has a thickness of 75 μm.
As a barrier layer, a laminated film obtained by vapor-depositing aluminum oxide to a thickness of 350 ° by a PVD method on an ETFE resin film having a thickness of m was used. A commercially available ethylene-vinyl acetate copolymer film having a thickness of 600 μm, containing a crosslinking agent and an ultraviolet absorber, and having a vinyl acetate content of 35% by weight is used for the film of the filler layer for the front surface and the back surface. did. The solar cell element is a solar cell element made of amorphous silicon. PVF film (thickness 38 μm), aluminum foil (thickness 50 μm),
A laminated film in which PVF films (thickness: 38 μm) were sequentially bonded by a dry lamination method was used. still,
For the vacuum lamination of this solar cell module, 150
30 ° C. was required for 30 minutes.

Using the solar cell modules of Examples 1 to 7 and Comparative Example 1 manufactured as described above as samples, JIS
Based on the test method of C8917: 1998, an environmental test was performed, the output of the photovoltaic power before and after the test was measured, the power generation efficiency [%], the output reduction rate [%] were calculated, and the adhesion of each laminated portion was measured. The working efficiency of the manufacturing process was evaluated, and the results are shown in Table 1.

[0055]

[Table 1]

As is clear from the results shown in Table 1, all the evaluation items of the solar cell modules of Examples 1 to 7 were good, whereas the solar cell module of Comparative Example 1 was good. Although the performance as a solar cell was good, the working efficiency of the manufacturing process was inferior and there was a problem in productivity. Although not shown in the table, Comparative Example 1
In solar cell modules, the thickness of the filler layer, the front cover film, and the back cover film cannot be reduced in terms of workability and productivity.
There is also a problem in terms of cost reduction.

[0057]

As described above in detail, according to the present invention, the performance, compactness, long-term reliability, etc. are excellent, and the steps for manufacturing a solar cell module can be simplified. Cover film, namely, a solar cell filler layer, a front cover film, and a back cover film that can be reduced in thickness, thereby improving productivity, resource saving, and cost reduction. It is possible to provide a solar cell module using the manufacturing method and the cover film.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating a configuration of a cover film of a solar cell according to the present invention. FIG. (B) is a schematic cross-sectional view of a cover film of a back solar cell used on the back side of the solar cell.

FIG. 2 is a schematic cross-sectional view illustrating a configuration of a solar cell module of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 front cover film 2, 2 ′ filler layer for solar cell 3 back cover film 4 solar cell element 10 cover film for front solar cell 20 cover film for rear solar cell 100 solar cell module

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Yamamoto 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Katsutoshi Konno 1-chome, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1 Dai-Nippon Printing Co., Ltd. F-term (reference) 4F100 AA00C AA00D AA19C AB11A AH02H AK01B AK17B AK68B AK68K AT00A BA03 BA04 BA07 BA10A BA10C BA10D CA07B CA23B CA30B EC032 EC182 EH232 EH462 EH66B00 JB09 JB09 JB094 DA08 LA16 5F051 AA05 EA18 GA05 JA04 JA05

Claims (10)

[Claims] 1. A solar cell cover film comprising a solar cell filler film mainly composed of a thermoplastic resin laminated on a solar cell front cover film or a back cover film. 2. The method according to claim 1, wherein the front cover film comprises a multilayer laminated film, and includes at least one of a fluororesin film and a weather-resistant film, and a vapor-deposited layer of an inorganic oxide or a vapor-deposited layer of an inorganic oxide as a barrier layer. The cover film for a solar cell according to claim 1, further comprising one of a composite layer and an inorganic-organic hybrid coat layer laminated thereon. 3. The solar cell cover film according to claim 1, wherein the front cover film has an ultraviolet shielding ability. 4. A front cover film having a thickness of 1
The cover film for a solar cell according to claim 1, wherein the thickness is from 0 μm to 70 μm. 5. The method according to claim 1, wherein the back cover film comprises a multilayer laminated film, and comprises at least an inorganic oxide vapor-deposited layer serving as a barrier layer, or an inorganic organic hybrid coat layer laminated thereon. Or a laminated film including a resin film having light reflectivity, or a laminated film including at least a metal foil layer or a metal deposition layer and a resin film. The cover film for a solar cell according to claim 1. 6. The thermoplastic resin is mainly composed of an ethylene-vinyl acetate copolymer containing a crosslinking agent and contains at least one of an ultraviolet absorber and a coupling agent. A cover film for a solar cell according to any one of claims 1 to 5. 7. The solar cell cover film according to claim 1, wherein the ethylene-vinyl acetate copolymer has a vinyl acetate content of 15 to 45% by weight. 8. The solar cell filler layer has a thickness of 50 μm.
8. The structure according to claim 1, wherein the thickness is in the range of m to 500 [mu] m.
The cover film for a solar cell according to any one of the above. 9. A method for producing a solar cell cover film, comprising laminating a solar cell filler layer mainly composed of a thermoplastic resin on a solar cell front cover film or a back cover film. A solar cell filler layer containing a thermoplastic resin as a main component is laminated on the front cover film or the back cover film by any one of a thermal lamination method, a dry lamination method, an extrusion lamination method, an extrusion coating method, and a calendar coating method. A method for producing a cover film for a solar cell, comprising: 10. A solar cell module, wherein the solar cell cover film according to claim 1 is used outside a solar cell element.