JP2002203980A - Solar cell module, solar cell array, solar cell integrated with building material, solar cell integrated with wall material, and solar cell integrated with roof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell module, a solar cell array, a solar cell integrated with building material, a solar cell integrated with wall material, and a solar cell integrated with roof in which adhesion of snow to the surface of the solar cell module can be improved. SOLUTION: The solar cell module comprises a coated photovoltaic element group connecting at least one photovoltaic element 305 wherein at least the most surface layer 309 of the coating material 312 on the light receiving face side contains particles produced by coating a UV absorbent containing at least a material having a critical surface tension of 15-35 mN/m and an inorganic compound with organosilicon and the water touch angle of the most surface layer 309 on the light receiving face side is not smaller than 110 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell module in which a group of at least one photovoltaic element is connected to a photovoltaic element is covered with a covering material, a solar cell array in which the module is installed, and a building material. Building material integrated solar cells,
The present invention relates to a wall material integrated solar cell integrated with a wall material, and a roof material integrated solar cell integrated with a roof material, in particular, a solar cell module, a solar cell array, and a building material having a coating material surface subjected to a snow adhesion preventing process. Integrated solar cell, wall material integrated solar cell,
And a roof material-integrated solar cell.

[0002]

2. Description of the Related Art A conventional solar cell module has a sectional structure as shown in FIG. That is, in FIG.
101 is glass, 102 is a photovoltaic element, 103 is a filler, and 104 is a back film.

[0003] Such a solar cell module has high wettability of water since its surface is made of glass, and is liable to snow and ice. Snow and icing on the surface of the solar cell module
Light transmission may be hindered and the conversion efficiency of the solar cell module may be reduced. In particular, when used as a roofing material for a house or the like, the load capacity of the building must be increased. Further, when snow or icing is partially formed, partial shading may occur, and the photovoltaic element may be damaged.

[0004] Such a solar cell module that energizes the solar cell module to generate heat and melts snow is disclosed in, for example, JP-A-8-340649. Also, JP-A-11-181339 and JP-A-11-17223
No. 9 discloses a hydrophilic coating material. These are for making the member surface hydrophilic with a hydrophilic coating material, and the adhesion of snow is reduced by the hydrophilicity. Further, JP-A-10-316820 discloses a member having a super-hydrophobic surface. This is to improve the flowability by super water repellency and prevent the adhesion of dirt. This discloses an application to a solar cell cover. It also discloses that super-water repellency prevents icing and snow.

[0005]

SUMMARY OF THE INVENTION Incidentally, Japanese Patent Application Laid-Open No.
The solar cell module disclosed in Japanese Patent No. 3406649 requires a separate lead storage battery or the like, which is costly. The publication does not disclose the snow-covered surface of the solar cell module and can melt snow, but does not disclose the flow of water or the like thereafter.
Therefore, in a solar cell module having a light-receiving surface side outermost layer of ordinary glass, unless the temperature rises,
Unless the energization is continued, the snow on the surface of the solar cell module is not removed.

Japanese Patent Application Laid-Open Nos. 11-181339 and 11-172239 also disclose application to a solar cell cover. However, when the temperature is relatively high, or when snow is wet snow, In this case, the adhesion of snow to the solar cell module surface increases.

[0007] Furthermore, Japanese Patent Application Laid-Open No. 10-316820 does not disclose any problems concerning snow accretion and power generation of the solar cell module.

The present invention has been made in view of the above problems, and has as its object to provide a solar cell module capable of improving snow adhesion to the surface of a solar cell module, and a solar cell array having the module grounded. Another object of the present invention is to provide a building material integrated solar cell integrated with a building material, a wall material integrated solar cell integrated with a wall material, and a roof material integrated solar cell integrated with a roof material.

[0009]

In order to achieve the above object, a solar cell module according to the present invention comprises a photovoltaic element group in which at least one or more photovoltaic elements are connected with a covering material. Wherein at least the outermost surface layer on the light-receiving surface side of the coating material has a critical surface tension of at least 1.
It comprises particles coated with an organosilicon and an ultraviolet absorber comprising a material of 5 to 35 mN / m and an inorganic compound, wherein the contact angle of water of the outermost light-receiving surface layer is 110 ° or more. is there.

In the above solar cell module, the material having a critical surface tension of 15 to 35 mN / m has a refractive index of 1.
Preferably it is less than 5.

Further, the critical surface tension is 15 to 35 mN.
/ M is preferably 0.5 μm or less.

Further, 80% of the particles of the ultraviolet absorber
It is preferable that the above particle diameter is 0.01 μm to 0.1 μm.

Further, it is preferable that the surface roughness of the outermost surface layer on the light receiving surface side is 1 μm or less.

Preferably, the solar cell module has a heat generating means.

[0015] In addition, the solar cell module preferably has a means for vibrating.

The solar cell array of the present invention is characterized in that the solar cell module of the present invention is installed at an installation angle of 20 to 45 °.

Further, a building material-integrated solar cell of the present invention is characterized in that the solar cell module of the present invention is integrated with a building material.

The solar cell module with integrated wall material of the present invention is characterized in that the solar cell module of the present invention is integrated with a wall material and installed on a wall at an installation angle of 70 to 130 °.

Further, the wall material-integrated solar cell of the present invention comprises:
The solar cell module of the present invention is integrated with a roof material,
It is installed on a roof at an installation angle of 20 to 70 °.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below, but the present invention is not limited to the embodiments.

FIG. 1 is a schematic diagram showing a cross-sectional structure of a solar cell module of the present invention. In FIG. 2, reference numeral 201 denotes a light-receiving surface side outermost layer, 202 denotes a photovoltaic element, 203 denotes a filler, and 204 denotes a back surface material.

Hereinafter, each component of the solar cell module of the present invention will be described.

(Light-receiving surface-side outermost layer) The light-receiving surface-side outermost layer 201 in the present invention contains a material having at least a critical surface tension of 15 to 35 mN / m. It is a layer of 110 ° or more. The form and configuration of the light-receiving surface side outermost layer 201 are not limited as long as the outermost layer on the light-receiving surface side satisfies the above-described characteristics. For example, besides directly forming the above-mentioned light receiving surface side outermost surface layer on the filler layer,
Two or more layers may be formed on the filler layer.

As a method of directly forming the above-mentioned light-receiving surface side outermost layer on the filler layer, a film having the above-mentioned properties is bonded to the filler, or a paint having the above-mentioned properties is applied on the filler. Direct coating and the like.

As a method for forming two or more layers on the filler layer, there is a method in which a base material is coated with a coating material having the above-mentioned characteristics, and the resultant is further bonded to the filler material. In the present invention, in consideration of the stability of the process, a method in which a base material coated with a paint is bonded to a filler is preferable. With this method, it can be manufactured by a conventional lamination method.

When coating a coating material on a substrate, the substrate preferably has a high transmittance. When coating with a thermosetting paint, the substrate is required to have high heat resistance. Furthermore, when coating with a paint containing a solvent or the like, high solvent resistance is required.

Examples of the base material satisfying the above-mentioned required characteristics include films, sheets and the like of glass, fluorine resin, polyester resin, polyimide resin, polycarbonate resin and the like. These substrates are preferably subjected to an easy-adhesion treatment in order to improve the adhesion of the paint and the adhesive force with the filler. Specific examples include corona discharge treatment and plasma treatment.

The coating material to be coated on these substrates is a material in which a material having a critical surface tension of 15 to 35 mN / m is dispersed in a binder resin in the form of particles. Critical surface tension preferably used in the present invention is 15 to 35 mN / m.
Specific examples of the material include polyethylene (critical surface tension: 28 to 36 mN / m) and polypropylene (critical surface tension: 29 to 34 mN / m).
mN / m), polystyrene (27-35 mN / m),
Polyvinylidene fluoride (24 to 26 mN / m), Polytetrafluoroethylene (18 to 22 mN / m), Polychlorinated trifluoride / tetrafluoroethylene copolymer (20)
２６26 mN / m), polypropylene hexafluoride (12-
18 mN / m), polytetrafluoroethylene-ethylene copolymer (27 to 28 mN / m), polyvinyl fluoride (2
7 to 29 mN / m) and a tetrafluoroethylene-6-fluoropropylene copolymer (17 to 18 mN / m).

Since the above-mentioned material is used on the light receiving surface side of the solar cell module, it is preferable that the material has a low refractive index. When the refractive index is high, the conversion efficiency of the solar cell module decreases due to reflection. The preferred refractive index is less than 1.5, more preferably less than 1.4. Specific materials having a refractive index of less than 1.5 include polyvinylidene fluoride (refractive index: 1.42), polytetrafluoroethylene-ethylene copolymer (1.40), and polyvinyl fluoride (refractive index: 1.46). ) And the like. Further, as a material having a molecular weight of less than 1.4, polytetrafluoroethylene (1.35) and tetrafluoroethylene-6-propylene copolymer (1.34)
And the like.

These critical surface tensions are 15 to 35 mN /
The resin m preferably has a small particle size. When the particle size is large, the transparency is reduced. It is generally said that if the particle size is half the wavelength, the transmittance does not decrease. In the present invention, the primary particle size is preferably 0.5 μm or less. These resins are formed into particles, dispersed in a binder resin, and coated as a paint. It is preferable that the binder resin has excellent weather resistance.

It is preferable that the binder resin has the same refractive index as that of the resin having a critical surface tension of 15 to 35 mN / m. As a specific material, a silicone-based or fluorine-based resin is preferable.

In addition to these resins, it is preferable that the outermost surface layer on the light-receiving surface side in the present invention contains an ultraviolet absorber. These ultraviolet absorbers not only increase the weather resistance of the above-mentioned critical surface tension of 15 to 35 mN / m resin or the binder resin, but also improve the weather resistance of the filler and the organic material used for the photovoltaic element. As the ultraviolet absorber mixed with the outermost surface layer on the light-receiving surface side, it is preferable to use an inorganic compound or a combination of an inorganic compound and an organic compound. An ultraviolet absorber composed of an inorganic compound is less likely to volatilize or bleed out.

Known inorganic compounds can be used. Specific examples include titanium oxide, iron oxide, zinc oxide, cerium oxide, yttrium oxide, zirconium oxide, and selenium oxide.

The shape of the ultraviolet absorber composed of these inorganic compounds may be in the form of particles or flakes, but is preferably as fine as possible. When the particle size increases, visible light and near-ultraviolet light required for power generation of the solar cell are absorbed, and the conversion efficiency of the solar cell is reduced. The specific particle size is preferably at least 80% of the particles, and preferably substantially all of the particles are in the range of 0.01 μm to 0.1 μm, more preferably 0.01 to 0.05 μm. If the particle size is smaller than this, the particles tend to aggregate.
If it is larger than this, it becomes opaque.

It is preferable that these ultraviolet absorbers have a low refractive index. The surface of the ultraviolet absorbent comprising the inorganic compound of the present invention is coated with organosilicon. If the coating amount is too small, it becomes difficult to improve the ultraviolet absorbing ability. Also, if the amount is too large, the effect corresponding to the amount cannot be expected, and it is not economical.

In the present invention, the organosilicon includes alkylpolysiloxane, alkylaryl (Ar
yl) Siloxanes such as polysiloxanes and alkylhydrogenpolysiloxanes, and silane coupling agents such as alkyltrimethoxysilane, γ-aminopropyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane.

The ultraviolet absorbent of the present invention may have a particle surface coated with an inorganic oxide such as aluminum or silicon or an inorganic hydrated oxide in addition to the organosilicon coating. In this case, an oxide such as alumina or silica is suitable as the coating material. This can give more favorable results on weather resistance and the like.

Examples of the organic compound include benzophenone type and benzotriazole type. Specifically, 2,4-dihydroxybenzophenone, 2-
Hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-n-dodecyloxybenzophenone, bis (5 -Benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'dimethoxybenzophenone, 2-
(2′-hydroxy-5′-methylphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl) phenyl] -benzotriazole, 2- (2′- (Hydroxy-3 ′, 5′-ditalbutyl-phenyl) -benzotriazole,
2- (2'-hydroxy-3'-tert-butyl-
5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-ditert-butyl-phenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3' , 5'-Ditertiary amyl) benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2'-methylenebis [4- (1,1,3,
3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol], phenyl salicylate, 4-tert-butylphenyl salicylate, ethyl-2-cyano-3-diphenylacrylate, 3-ethylhexyl-2- Cyano-3,3'-diphenyl acrylate, 2-ethoxy-2'-ethyloxalic acid bisanilide and the like can be mentioned.

These ultraviolet absorbers are added in an amount of about 0.01 to 3% by weight based on the solid content of the paint. In particular, when an ultraviolet absorber composed of an inorganic compound is used, a sufficient effect is exhibited even if the added weight is 0.5% or less.

These materials are mixed to form a paint. Known methods can be used for applying these paints.
For example, spray coating, dip coating, flow coating, spin coating,
Roll coating, brush coating, sponge coating and the like can be mentioned. These paints are preferably cured for improving weather resistance and heat resistance. As the curing method, heat curing,
Room temperature curing, ultraviolet curing and the like can be mentioned.

It is preferable that the outermost surface layer on the light receiving surface side has a roughened surface. To increase the contact angle, the surface roughness is preferably 1 μm or less. By thinning the coating film, particles of a resin having a critical surface tension of 15 to 35 mN / m or particles of an ultraviolet absorber composed of an inorganic compound are exposed on the surface, and the surface of the outermost surface layer on the light receiving surface side has minute irregularities. Becomes When the thickness of the coating film is large, the surface may be processed by sandblasting or the like.

(Filler) As the filler in the present invention, known fillers can be used. Fillers for solar cell modules are required to have excellent weather resistance, heat resistance, and adhesive strength. If the filler resin itself does not satisfy the above properties, additives are added. For example, in order to improve weather resistance, an ultraviolet ray inhibitor, a light stabilizer, an antioxidant, a secondary antioxidant, and the like are added.

When an ultraviolet absorber is contained in the outermost surface layer on the light receiving surface side in the present invention, it is not necessary to mix the ultraviolet absorber. The UV absorber prevents light deterioration of the filler. An antioxidant is added to prevent thermal oxidation of the resin.

In the case of a roofing-integrated solar cell module, since the operating temperature of the solar module is 20 to 40 ° C. higher than the ambient temperature, it is necessary to use a resin having high heat resistance. When the heat resistance of the resin itself is low, the heat resistance can be increased by crosslinking. As a method of crosslinking,
Although not particularly limited, a method of adding an organic peroxide to a resin in advance and heating the resin is preferably used.
The organic peroxide is not particularly limited as long as it has a high crosslinking efficiency of the filler and does not adversely affect the weather resistance of the filler. Further, a coupling agent is added in order to improve the adhesive strength between the outermost light-receiving surface layer and the photovoltaic element.

Specific examples of the filler include EVA, an ethylene-vinyl monomer copolymer, ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl acrylate copolymer (EMA), and butyral. Examples thereof include a polyolefin resin such as a resin, a urethane resin, and a silicone resin.

(Photovoltaic Element) The photovoltaic element used in the present invention is not particularly limited. All types of photovoltaic elements can be used. The output of the photovoltaic element group to which these photovoltaic elements are connected is reduced by shading a part of the group. In that case, a reverse voltage may be generated in the photovoltaic element in the shadow, and the photovoltaic element may be destroyed.

Further, in a system in which a plurality of solar cell modules are connected, the output is reduced. In order to prevent such a problem, a method of connecting a bypass diode may be adopted. However, connection and the like are troublesome, and the number of parts and the like increase, which increases the cost.

In the present invention, since the occurrence of shadows on the photovoltaic element due to snowfall is reduced, the present invention can also be used for a photovoltaic element without connecting a bypass diode and a solar cell module.

(Back Material) The back material used in the present invention is not particularly limited, but a flexible member made of a resin film or the like, a member for imparting rigidity to a solar cell module such as a steel plate, or the like can be used. No.

When a flexible member is used, it can be bonded directly to the filler on the back side. It is preferable that these flexible members have a high insulating property in order to complete the insulation between the photovoltaic element and the outside. When the insulating property of the member itself is low, the insulating property can be improved by increasing the film thickness. When the member itself is conductive, it is possible to improve the insulation by increasing the thickness of the filler between the photovoltaic element and the backing material.

When the photovoltaic element has flexibility, it is preferable that these members have flexibility that does not impair the flexibility of the photovoltaic element. When the flexibility of the photovoltaic element is low, it is preferable that the photovoltaic element has flexibility enough to prevent the destruction of the photovoltaic element.

Specific materials used for these flexible members include polyethylene, polypropylene, polyethylene terephthalate, polyethylene naphthalate, and the like.
Nylon, polyphenylene sulfide, polyimide,
Examples include resin materials such as polycarbonate, acrylic, and fluororesin, and woven, nonwoven, and metal foils of glass fiber.

In order to prevent moisture from entering the photovoltaic element, it is also possible to use a metal foil in which a resin is bonded to both sides. These members are preferably subjected to an easy-adhesion treatment in order to improve the adhesive strength with the filler. Specifically, a corona discharge treatment, a plasma treatment and the like can be mentioned.

It is preferable that these members have high weather resistance. However, since the light intensity is lower than that of the light receiving surface side, the members do not need to have as high weather resistance as the members used on the light receiving surface side.

On the other hand, when a solar cell module is used as a building material, a rigid member such as a steel plate is used.
These rigid members may be directly bonded on the filler, but when the material is a metal steel plate or the like, a multilayer structure such as a back film, an adhesive, and a rigid member on the filler is required. Is preferred.

As the back film, the same film as the flexible member can be used. Further, non-woven fabrics and woven fabrics made of glass fibers and plastic fibers can also be used.

The adhesive used in the present invention is preferably the same as the filler. Further, in the present invention, it is also possible to laminate up to the above-mentioned back film in advance and to bond it to an existing building material or the like. In this case, a solvent-type adhesive or the like can be used.

The rigid member supports the solar cell module. The installation form of the solar cell module includes a case where the solar cell module is used as a building material integrated type and a case where a frame is attached to the module and installed on a gantry via the frame. Solar cell modules for these applications need to have sufficient rigidity. Normally wind speed 30-40m
It is said that it is necessary to have a rigidity that can endure per second. In particular, a module in which the surface is covered with a fluorine film or the like without using a glass plate as the surface member is effective in imparting rigidity by the supporting base material. The support substrate used in the present invention is a coated steel plate, glass fiber reinforced plastic, hard plastic,
Timber and the like can be mentioned.

In the case of a building material integrated type, it is preferable to use a structure in which the rigidity is improved by bending, and at the same time, the structure is fitted into a channel as an attachment member. Steel sheets and stainless steel sheets are suitable for these processes. These materials are unlikely to melt or deform even in high-temperature flames.
It is also suitably used as roofing material. For such a use, it is preferable that the rust prevention property and the weather resistance are excellent. Due to the above characteristics, coating with a coating excellent in weather resistance is generally performed.

(Heat generating means) In the present invention, a heat generating means can be incorporated in the solar cell module. This provides for a large amount of snowfall even if the snow adhesion on the surface is reduced. Examples of the heat generating means include a method in which the heat generating means is incorporated in the solar cell module in advance, and a method in which the heat generating means is newly attached to the solar cell module.

In the case of a roofing material, it is also possible to use heat from a house. Specific examples include a method of embedding a heating wire in a solar cell module and a method of installing an infrared heater on the back side of the solar cell module.

When the back material of the solar cell module has conductivity, electricity can be applied to the back material to generate heat. Furthermore, it is also possible to energize the photovoltaic element to generate heat.

(Vibrating Means) In the present invention, it is possible to incorporate a vibrating means into the solar cell module. This provides for the case of a large amount of snowfall even if the snow adhesion on the surface is reduced as in the case of the heating means. This is an effective means especially when the solar cell module has flexibility.

As a means for vibrating, a known method can be used. For example, it is also possible to vibrate the solar cell module directly with a motor or the like, or send wind to the solar cell module to vibrate.

(Installation Angle) The installation angle of the solar cell module is set at an angle that can receive sunlight most efficiently. In general, it depends on the latitude of the installation area, but in some cases, an angle different from the angle is often more efficient. When used as a roofing material, the angle is determined by the balance with the house.

In the present invention, the installation angle is preferably set to 20 to 70 ° in order to reduce the adhesion of snow.
Note that the installation angle in the present invention refers to a rising angle from a horizontal plane.

[0067]

Embodiments of the present invention will be described below in detail with reference to the drawings. However, the present invention is not limited to these embodiments.

Example 1 In this example, a solar cell module having the structure shown in FIG. 2 was prepared as an evaluation module.

As shown in FIG. 2, the solar cell module has a reinforcing plate 301 and a laminated film 31 of a back surface covering material.
1. Photovoltaic element 305, laminated member 312 of surface coating material
Was prepared by first preparing.

Hereinafter, each component of the solar cell module of this embodiment will be described.

(Reinforcing Plate) As the reinforcing plate 301, a galvanized steel plate (0.4 mm thick) was prepared. On the reinforcing plate,
Two holes (15φ) for taking out the back electrode were previously formed.

(Laminated Film of Back Coating Material) As a laminated film 311 of the back coating material, a double-sided corona-treated 2
Axial stretched polyethylene terephthalate film 303
Ethylene-vinyl acetate copolymer (EVA) (vinyl acetate content 2
8 parts by weight) 100 parts, 1.5 parts of t-butylperoxy 2-ethylhexyl carbonate as a crosslinking agent, 0.3 parts by weight of 2-hydroxy-4-n-octoxybenzophenone as an ultraviolet absorber, and as an antioxidant 0.2 parts by weight of tris (mono-nonylphenyl) phosphite,
(2,2,6,6-tetramethyl-4
0.1 part by weight of (piperidyl) sebacate was mixed, and back-side sealing materials 302 and 304 each having a thickness of 200 μm were laminated using an extruder and a T-die.

A 15 μm emboss was applied to both sides of the laminated film by embossing rolls. Further, a 6φ hole was punched at a position corresponding to the electrode extraction of the photovoltaic element.

(Photovoltaic Element) As the photovoltaic element 305, an amorphous silicon photovoltaic element was prepared.

(Preparation of Laminated Member of Surface Coating Material) The lamination member 312 of the surface coating material was prepared by the following method. As the surface film 307, an ethylene-tetrafluoroethylene copolymer (ETFE) (50 μm in thickness) was used.

Both surfaces were subjected to plasma treatment, and one surface thereof was coated with the outermost surface layer 309 on the light receiving surface side. The outermost surface layer on the light-receiving surface side was a coating material in which particles of polytetrafluoroethylene and particles of titanium oxide treated with alkyltrimethoxysilane were finely and uniformly dispersed in a fluororesin. The paint was spray coated on the film and cured. Further, the finished coating film was processed by sand blasting so that the surface had a surface roughness of 0.8 μm. The contact angle of water of the light-receiving surface side outermost layer 309 was 140 °.

On the opposite surface, a surface sealing material 306 having a thickness of 460 μm was laminated by using an extruder and a T-die.

(Coating Step) An embodiment using a double vacuum laminating apparatus will be described. Details of the device will not be described here.

The above-described vacuum device is provided with PF to prevent contamination.
A film (thickness: 50 μm) is laid, and the reinforcing plate 301 thus prepared, the back surface covering material 311, the photovoltaic element 30
5. The surface coating material 312 was laminated and laminated. The pressure was reduced to about 1.3 × 10 ³ Pa. After the pressure was sufficiently reduced, the temperature was raised to 175 ° C. in 30 minutes while continuing the vacuum suction, and was taken out after 15 minutes. Thereafter, the mixture was cooled to room temperature while continuing the vacuum suction. Thus, a plurality of photovoltaic element modules were obtained.

(Heat generating means) In this embodiment, the reinforcing plate 301 is energized as the heat generating means. The energization time was 30 seconds.

The obtained solar cell module was evaluated by the following method.

(Snow Acceleration Test) Snow accretion was evaluated on a part of the solar cell module cut into a 100 mm square using an artificial snowfall machine. The time for snowfall was 10 minutes. Installation angle is 30
° and 60 °, and the temperature was -5 ° C and 2 ° C. The evaluation results are shown in Table 1 based on the following evaluation criteria. That is, ◎: those which do not cause snow accretion ○: those which cause snow accretion but will soon be resolved ×: those which remain snow accretion

(Weather Resistance Test) A part of the solar cell module cut into a square of 100 mm was put into a sunshine weather meter, and 2,000 cycles were performed with 48 minutes of light irradiation and 12 minutes of rainfall as one cycle. The change in appearance of the sample in the solar cell module was evaluated. The evaluation results are shown in Table 1 based on the following evaluation criteria. ○: no change in appearance ×: peeling or the like

Example 2 Example 1 was followed except that zinc oxide particles treated with alkyltrimethysilane were used instead of titanium oxide particles treated with alkyltrimethysilane. . The contact angle of water of the outermost light-receiving surface layer in this example was 140 °. Table 1 shows the evaluation results.

Example 3 Example 1 was followed, except that polyvinylidene fluoride was used instead of polytetrafluoroethylene. The contact angle of water on the outermost surface layer on the light-receiving surface side in this example was 130 °. Table 1 shows the evaluation results.

Example 4 Example 1 was followed except that no sandblasting was performed. The contact angle of water on the light-receiving surface side outermost layer in this example was 120 °. Table 1 shows the evaluation results.

Example 5 Example 1 was followed except that no current was applied. Table 1 shows the evaluation results.

Comparative Example 1 Example 1 was followed except that the outermost surface layer on the light-receiving surface side was not formed. Table 1 shows the evaluation results.

[0089]

[Table 1]

As is apparent from Table 1, at least the outermost surface layer on the light receiving surface side has a critical surface tension of at least 15 to 35 m.
N / m particles and an ultraviolet absorber composed of an inorganic compound are coated with organosilicon, and the light receiving surface side outermost layer has a water contact angle of 110 ° or more to form a layer. It is greatly reduced. Thereby, destruction of the photovoltaic element can be prevented.

The solar cell module according to the present invention is not limited to the embodiments described above, and can be variously modified within the scope of the invention.

[0092]

As described above, according to the present invention,
At least the outermost layer on the light-receiving surface side of the solar cell module includes particles coated with an organosilicon compound and an ultraviolet absorber made of a material having at least a critical surface tension of 15 to 35 mN / m and an inorganic compound. By setting the contact angle to 110 ° or more, the adhesion of snow to the solar cell module can be reduced, and the weather resistance can be further improved.

The surface roughness of the outermost surface layer on the light receiving surface side is 1 μm.
m or less, the adhesion of snow can be further reduced.

Further, since the solar cell module has heat generating means and / or the solar cell module has vibration means, even if snow adheres, snow can be removed.

In particular, when these solar cell modules are used as building materials, the design for building strength can be simplified, and accidents due to falling snow can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a cross-sectional configuration of a solar cell module of the present invention.

FIG. 2 is a schematic diagram illustrating a cross-sectional configuration of a solar cell module in Example 1.

FIG. 3 is a schematic diagram showing a cross-sectional configuration of a conventional solar cell module.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Glass 102 Photovoltaic element 103 Filler 104 Back film 201 Light receiving surface side outermost layer 202 Photovoltaic element 203 Filler 204 Back material 301 Reinforcement plate 302 Back seal material 1 303 Back film 304 Back seal material 2 311 Laminated film of back surface covering material 305 Photovoltaic element 306 Surface sealing material 307 Surface member 309 Light receiving surface side outermost surface layer 312 Surface covering material laminated member

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidenori Shiotsuka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Ichiro Kataoka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated F term (reference) 5F051 AA05 JA04 JA05 JA10 JA11 JA16 JA20 KA10

Claims (11)

[Claims] 1. A solar cell module in which a photovoltaic element group in which at least one or more photovoltaic elements are connected is covered with a coating material, wherein at least the light receiving surface side outermost layer of the coating material has a critical surface tension of at least 15. And an ultraviolet absorber composed of an inorganic compound and a material coated with an organosilicon, and the light-receiving surface side outermost layer has a water contact angle of 110.
° or more. 2. The critical surface tension is 15 to 35 mN / m.
2. The solar cell module according to claim 1, wherein the material has a refractive index of less than 1.5. 3. The critical surface tension is 15 to 35 mN / m.
3. The solar cell module according to claim 1, wherein the material has a primary particle size of 0.5 μm or less. 4. 4. The solar cell module according to claim 1, wherein a particle diameter of 80% or more of the particles of the ultraviolet absorbent is 0.01 μm to 0.1 μm. 5. The light-receiving surface side outermost surface layer has a surface roughness of 1 μm.
The solar cell module according to any one of claims 1 to 4, wherein m is equal to or less than m. 6. The solar cell module according to claim 1, wherein said solar cell module has a heat generating means. 7. The solar cell module according to claim 1, wherein said solar cell module has means for vibrating. 8. A solar cell array, wherein the solar cell module according to claim 1 is installed at an installation angle of 20 to 45 °. 9. A solar cell module integrated with a building material, wherein the solar cell module according to claim 1 is integrated with a building material. 10. A wall material-integrated solar cell, wherein the solar cell module according to any one of claims 1 to 7 is integrated with a wall material and installed on a wall at an installation angle of 70 to 130 °. 11. A wall material-integrated solar cell, wherein the solar cell module according to claim 1 is integrated with a roof material and installed on the roof at an installation angle of 20 to 70 °.