JP2010232569A - Protective sheet for solar cell module, and solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a protective sheet for a solar cell module small in an environmental load, and excelling in adhesiveness between a base material sheet and a weather-resistance layer formed on the base material sheet or a gas barrier layer formed as desired, and weather resistance. <P>SOLUTION: This protective sheet for a solar cell includes the base material sheet, and a silane compound layer of a foremost layer laminated on the base material sheet. It is preferable that a gas barrier layer obtained by implanting ions into a polyorganosiloxane layer is laminated on the base material sheet. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a surface protection sheet for a solar cell module, a back surface protection sheet, and a solar cell module including the same.

A solar cell module, which is a device that converts solar light energy into electrical energy, has attracted attention as a system that can generate power without discharging carbon dioxide. The solar cell module is required to have high power generation efficiency and durability that can withstand long-term use even when used outdoors.
The main configuration of the solar cell module includes a photovoltaic cell that is a photovoltaic device, a sealing material that is an electrical insulator that prevents a short circuit in an electric circuit, and a housing that encloses them in a sealed state. A surface protection sheet and a back surface protection sheet are bonded to the light receiving surface side (front surface side) and the back surface side of the solar cell module, respectively, to prevent water vapor from entering the solar cell module. Such a protective sheet for a solar cell module is required to have excellent water vapor barrier properties and weather resistance, and to be excellent in adhesion to the sealing material of the solar cell module.
Conventionally, as a technique for improving water vapor barrier properties, weather resistance, and adhesion to a sealing material as a protective sheet for a solar cell module, for example, techniques disclosed in Patent Documents 1 and 2 have been proposed.

Patent Document 1 discloses a sheet including a fluororesin film layer having a silicon oxide thin film formed as a gas barrier layer on the surface, which is used as a protective layer of a solar cell module, and the sheet has an oxygen permeability of 5 cc / m ^2. • Day · atm or less, water vapor transmission rate of 5 g / m ² · day or less, light transmittance of 80% or more, silicon oxide thin film thickness of 150 to 500 mm, and adhesion strength of the film of 200 g The protective sheet for solar cell modules characterized by being / 15 mm or more is disclosed.
Patent Document 2 discloses a back sheet for a solar cell module in which a cured coating film of a curable functional group-containing fluorine-containing paint is formed as a weather resistant layer on at least one surface of a water-impermeable sheet. .

JP-A-10-308521 WO2007 / 010706

However, the protective sheet containing a halogen compound disclosed in Patent Documents 1 and 2 may generate harmful substances when incinerated, has a high environmental load, and is not preferred for use from the viewpoint of waste disposal.
In addition, the protective sheet disclosed in Patent Document 1 has a problem that the material used in the process of providing the fluororesin film and the silicon oxide thin film is expensive, and the base material not subjected to pretreatment is oxidized with silicon. In a film in which a thin film is laminated, the flexibility of the silicon oxide thin film is poor and the adhesion between the base material and the silicon oxide thin film is weak, so that there is a problem that the bending resistance is low.
In addition, the back sheet disclosed in Patent Document 2 has a high cost because of the high cost of the fluorine coating used, and the adhesion between the substrate and the cured coating film of the fluorine coating is poor. In order to improve this, additional additives have been added, but it is still not sufficient.

  The present invention has been made in view of the above circumstances, has a small environmental load, and has excellent adhesion and weather resistance between a base sheet and a weather resistant layer provided on the base sheet or a gas barrier layer provided as desired. It aims at providing the protection sheet for battery modules.

  In order to achieve the above object, the present invention provides a protective sheet for a solar cell module, comprising a base sheet and a silane compound layer laminated on the base sheet. This silane compound layer functions as a weather resistant layer.

  In the protective sheet for a solar cell module of the present invention, it is preferable that a gas barrier layer is laminated on the base sheet.

  In the protective sheet for a solar cell module of the present invention, the silane compound layer is composed of one or more silane compounds selected from the group consisting of organic polysilazane, inorganic polysilazane, polycarbosilane, polysilane, and polyorganosiloxane. It is preferable.

  In the protective sheet for a solar cell module of the present invention, the gas barrier layer is preferably obtained by ion implantation into the polyorganosiloxane layer.

In the protective sheet for a solar cell module of the present invention, ions injected into the polyorganosiloxane layer are selected from the group consisting of H ₂ , He, N ₂ , O ₂ , Ne, Ar, Kr, and Xe. Or it is preferable to produce | generate from 2 or more types of gas.

  In the protective sheet for a solar cell module of the present invention, it is preferable that a voltage applied when ions are implanted into the polyorganosiloxane layer is in a range of −1 to −50 kV.

  In the protective sheet for a solar cell module of the present invention, a pigment may be added to the substrate sheet.

  The protective sheet for a solar cell module of the present invention is preferably made of a material containing no halogen.

  The present invention also provides a solar cell module in which the above-described protective sheet for a solar cell module of the present invention is bonded to one or both of the front surface and the back surface.

Since the protective sheet for a solar cell module of the present invention does not contain a halogen (F, Cl, Br, etc.) that has a high environmental load, it can suppress the generation of harmful substances when incinerated.
Moreover, the silane compound layer is excellent in adhesiveness with the base material sheet, and problems such as peeling of the silane compound layer hardly occur.
Furthermore, by setting it as the structure by which the gas barrier layer was laminated | stacked on the base material sheet, it becomes a protective sheet which has the outstanding gas barrier property and a weather resistance, and can be preferably used as a protective sheet for solar cell modules.

It is sectional drawing of 1st Embodiment of the protection sheet for solar cell modules of this invention. It is sectional drawing of 2nd Embodiment of the protection sheet for solar cell modules of this invention. It is sectional drawing of 3rd Embodiment of the protection sheet for solar cell modules of this invention. It is the schematic diagram which showed the structure of the solar cell module of this invention. It is the block diagram which showed the outline of the plasma ion implantation apparatus.

FIG. 4 is a schematic view showing a configuration of a solar cell module using the solar cell module protective sheet (hereinafter abbreviated as a protective sheet) of the present invention.
As illustrated in FIG. 4, the configuration of the solar cell module 50 includes a surface protection sheet 10, a back surface protection sheet 20, a sealing material 30, and solar cells 40. In order to give the solar cell module the weather resistance and durability that can withstand long-term use outdoors and indoors, the solar cell 40 and the sealing material 30 are protected from wind and rain, moisture, dust, mechanical impact, etc. It is necessary to keep the inside of the solar cell module sealed from the outside air completely. For this reason, the surface protection sheet 10 and the back surface protection sheet 20 are required to have excellent water vapor barrier properties and weather resistance.

  Drawing 1 is a mimetic diagram showing the section of a 1st embodiment of a protection sheet of the present invention. 1 and FIG. 2 and FIG. 3 to be described later exemplify the case where the protective sheet of the present invention is applied as the back surface protective sheet 20, but the protective sheet of the present invention can also be applied as the front surface protective sheet 10. Needless to say. In the following description, when an aluminum-deposited PET sheet is used as the base material sheet 21 or a white PET sheet to which a white pigment such as titanium dioxide is added is used, it is intended to be applied to the back surface protection sheet 20. And when applying as the surface protection sheet 10, a transparent base material sheet is used.

  The protective sheet 20 </ b> A of the present embodiment has a configuration in which a silane compound layer 22 is laminated on one surface side of the substrate sheet 21.

  As the resin sheet that can be used as the base material sheet 21, one that is generally used as a resin sheet in a back sheet for a solar cell module can be used. For example, polyethylene, polypropylene, polystyrene, polymethyl methacrylate, polytetrafluoroethylene, polyamide (nylon 6, nylon 66), polyacrylonitrile, polyvinyl chloride, polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate Examples thereof include a sheet made of a polymer such as (PEN), polyoxymethylene, polycarbonate, polyphenylene oxide, polyester urethane, poly m-phenylene isophthalamide, poly p-phenylene terephthalamide. Especially, the sheet | seat which consists of polyesters, such as PET, PBT, and PEN, is preferable, and a PET sheet | seat is mentioned as a preferable thing from a mechanical strength and an insulating viewpoint more specifically.

  What is necessary is just to select as thickness of the said base material sheet 21 based on the electrical insulation which a solar cell system requires. For example, when the substrate sheet 21 is a resin sheet, the film thickness is preferably in the range of 10 to 300 μm. More specifically, when the substrate sheet 21 is a PET sheet, the thickness of the PET sheet is preferably in the range of 10 to 300 μm from the viewpoint of lightness and electrical insulation, The range of 200 μm is more preferable, and the range of 50 to 150 μm is more preferable.

Further, from the viewpoint of water vapor barrier properties, the surface modification treatment of the base material sheet 21 can be performed. For example, by weathering silica (SiO ₂ ) and / or alumina (Al ₂ O ₃ ) on the PET sheet, the weather resistance, moisture resistance, etc. of the back sheet can be enhanced. The silica and / or alumina vapor deposition treatment may be performed on both surfaces of the substrate sheet 21 or only on one of the surfaces.
Furthermore, from the viewpoint of water vapor barrier properties, a sheet made of a metal foil such as an aluminum foil or an aluminum-iron alloy foil, an Al vapor-deposited PET sheet, an Al foil-laminated PET sheet, or the like can be used as the base sheet 21.
Furthermore, as the base material sheet 21, a PET sheet in which a pigment such as titanium dioxide is dispersed can be used from the viewpoint of improving the reflectance. An example of such a pigment-dispersed PET sheet is “Lumirror E20” manufactured by Toray Industries, Inc. In addition, when using a protection sheet with a high reflectance as the back surface protection sheet 20 of the solar cell module 50, the reflection efficiency which reflects the light which escapes through the clearance gap between the photovoltaic cells 40, and returns to the photovoltaic cell 40 side becomes high. The power generation efficiency of the module can be increased.

  The silane compound layer 22 is preferably made of one or more silane compounds selected from the group consisting of organic polysilazane, inorganic polysilazane, polycarbosilane, polysilane, and polyorganosiloxane.

Examples of the organic polysilazane include methylpolysilazane, hexamethyldisilazane, tetramethyldisilazane, divinyltetramethyldisilazane, cyclic dimethyldisilazane, and the like. An example of the product name is “tutoProm bright”.
Examples of the inorganic polysilazane include perhydropolysilazane, and examples of the coating liquid containing the inorganic polysilazane include trade name “AQUAMICA NP110” manufactured by AZ Electronic Materials.
As the polycarbosilane, a polycarbosilane having a weight average molecular weight (Mw) in the range of 500 to 100,000 is preferable. As a coating liquid containing this type of polycarbosilane, for example, trade name “Nippi” manufactured by Nippon Carbon Co., Ltd. Type S ”(Mw = 4000).
Examples of the polysilane include polydimethylsilane, polydiethylsilane, polyphenylmethylsilane, and the like. Examples of the coating liquid containing the polysilane include polyphenylmethylsilane (Ossol SI-10, manufactured by Osaka Gas Chemical Co., Ltd.). Etc.
Examples of the polyorganosiloxane include polydimethylsiloxane and polydiethylsiloxane. Examples of the coating liquid containing the polyorganosiloxane include trade name “KS847H” manufactured by Shin-Etsu Chemical Co., Ltd.

  The silane compound layer 22 is formed by applying a coating liquid containing the organic polysilazane, inorganic polysilazane, polycarbosilane, polysilane, or polyorganosiloxane on the base sheet 21 by a known method such as a bar coating method, followed by heat curing. Can be formed.

  The film thickness of the silane compound layer 22 is preferably in the range of 30 nm to 300 μm, more preferably in the range of 50 nm to 100 μm, and still more preferably in the range of 100 nm to 1 μm. When the film thickness of the silane compound layer 22 is less than the above range, the antifouling property of the outermost layer cannot be sufficiently obtained, and dirt easily adheres. Even if the film thickness of the silane compound layer 22 exceeds the above range, the antifouling property of the outermost layer is not further improved, and this is not preferable because the cost increases.

20 A of protective sheets of this embodiment adhere | attach the other surface side (surface opposite side of the silane compound layer 22) of the base material sheet 21 on the surface side or back surface side of the sealing material 30 of the solar cell module 50, and a solar cell. It is used as a surface protection sheet for modules or a back surface protection sheet.
Since the protective sheet 20A of the present embodiment does not contain halogen (F, Cl, Br, etc.) with high environmental load, it can suppress the generation of harmful substances during incineration and has low environmental load.
Moreover, the silane compound layer 22 is excellent in antifouling property, and is also excellent in adhesiveness with the base material sheet 21, and troubles, such as peeling of a silane compound layer, do not occur easily.

FIG. 2 is a cross-sectional view showing a second embodiment of the protective sheet of the present invention.
The protective sheet 20 </ b> B of the present embodiment has a configuration in which a gas barrier layer 23 is laminated on one surface side of the base sheet 21 and a silane compound layer 22 is laminated on the gas barrier layer 23.

  In the present invention, the gas barrier layer 23 is preferably a gas barrier layer 23 obtained by ion implantation into the polyorganosiloxane layer. This polyorganosiloxane layer can be formed by applying a coating liquid containing polyorganosiloxane onto the substrate sheet by a well-known method such as a bar coating method, followed by heat curing. The thickness of the polyorganosiloxane layer serving as the gas barrier layer 23 is preferably in the range of 20 nm to 10 μm, and more preferably in the range of 30 nm to 1 μm.

  The method of performing ion implantation on the surface of the polyorganosiloxane layer formed on the substrate sheet 21 is not particularly limited as long as the effect of the present invention is not impaired, and can be performed by a known method. . For example, a method in which ion implantation is performed on a polyorganosiloxane layer on a long base sheet using a plasma ion implantation apparatus described in JP-A-2006-070238 is a preferred method.

  If the plasma ion implantation apparatus is used, a base sheet (hereinafter also referred to as a base sheet) in which a pressure during ion implantation is set to 0.01 to 0.5 Pa and a polyorganosiloxane layer is formed in a plasma atmosphere. A uniform ion implantation layer can be formed on the surface of the polyorganosiloxane layer by plasma ion implantation (PBII: Plasma-Based Ion Implantation) while being conveyed in a certain direction. In this case, since a long base sheet can be continuously ion-implanted while being conveyed in a certain direction, it is efficient and suitable for mass production.

  The plasma ion implantation apparatus generates plasma only by an electric field generated by application of a high voltage pulse without using an external electric field generated by a high frequency power source such as a microwave. That is, in the plasma ion implantation apparatus, a long base sheet is conveyed in a certain direction, and at the same time, a negative high voltage is applied to the base sheet to generate plasma, and ions in the plasma are Is injected into the surface of the polyorganosiloxane layer of the substrate sheet to form an ion-implanted layer.

The configuration of the plasma ion implantation apparatus is shown in FIG.
In FIG. 5 (a), 51a is a long base sheet, 61 is a chamber, 70 is a turbo molecular pump, 53 is an unwinding roll for feeding the base sheet 51a before ion implantation, and 55 is ion-implanted. A winding roll for winding the substrate sheet 51 into a roll, 52 is a high-voltage applied rotation can, 60 is a gas inlet, and 57 is a high-voltage pulse power source. FIG. 5B is a perspective view of the high-voltage applying rotation can 52, and 65 is a high-voltage introduction terminal (feedthrough).

  In the continuous ion implantation apparatus shown in FIG. 5, the base sheet 51 a is transported in the chamber 61 from the unwinding roll 53 in the direction of arrow A in FIG. 5, passes through the high voltage application rotation can 52, and is wound. It is wound on a take-up roll 55. The method for winding the base sheet 51a, the method for transporting the base sheet 51a, and the like are not particularly limited. For example, the base sheet 51a is transported by rotating the high-voltage applying rotation can 52 at a constant speed. Is done. The rotation of the high voltage application rotation can 52 is performed by rotating the central shaft 63 of the high voltage introduction terminal 65 by a motor.

  The high-voltage introduction terminal 65 and the plurality of delivery rolls 56 that the base sheet 51a contacts are made of an insulator, and are formed, for example, by coating the surface of alumina with a resin such as polytetrafluoroethylene (PTFE). . The high voltage application rotation can 52 is made of a conductor, and is formed of, for example, stainless steel, SUS (Steel special Use Stainless), or the like.

  The conveyance speed of the base material sheet 51a can be set as appropriate. Ion implantation is performed on the surface of the polyorganosiloxane layer of the substrate sheet until the substrate sheet 51a is conveyed from the unwinding roll 53 and wound on the winding roll 55, and a desired ion-implanted layer is formed. There is no particular limitation as long as it is a speed at which sufficient time is secured. The winding speed (line speed) of the base sheet is usually 0.1 to 2 m / min, preferably 0.2 to 0.7 m / min, although it depends on the applied voltage and the diameter of the high voltage applied rotating can. .

As a procedure of the ion implantation process, first, the inside of the chamber 61 is evacuated by the turbo molecular pump 70 to reduce the pressure. The degree of vacuum is usually 1.0 × 10 ^{−4 to} 3.0 × 10 ⁻³ Pa.

Next, an ion implantation gas is introduced into the chamber 61 from the gas introduction port 60.
The ion implantation gas used here is preferably one or more gases selected from the group consisting of H ₂ , He, N ₂ , O ₂ , Ne, Ar, Kr, and Xe. Among these, Ar, He, and N ₂ are more preferable.

  Next, the negative high voltage pulse 59 is applied to the high voltage application rotary can from the high voltage pulse power source 57 through the high voltage introduction terminal 65 while the base sheet 51a is conveyed in the direction of A in FIG.

  When a negative high voltage is applied to the high voltage application rotation can 52, a plasma of ion implantation gas is generated along the base sheet 51a around the high voltage application rotation can 52, and ions in the plasma are induced. Then, it is injected into the surface of the polyorganosiloxane layer of the base material sheet 51a wound around the outer periphery of the high voltage application rotary can 52 (arrow B in FIG. 5A). When ions are implanted into the surface portion of the polyorganosiloxane layer, the surface portion is modified to form an ion implanted layer on the surface portion.

The pressure during ion implantation (pressure during plasma ion implantation) is preferably 0.01 to 1 Pa. The pulse width when generating plasma is preferably 1 to 15 μsec.
When the pressure during plasma ion implantation and the pulse width when generating plasma are within the above ranges, a uniform ion implantation layer can be formed on the surface of the polyorganosiloxane layer. Can be increased.

  The applied voltage when applying a negative high voltage to the high-voltage applying rotation can 52 is usually -1 kV to -50 kV, preferably -1 kV to -30 kV, more preferably -5 kV to -20 kV. When the applied voltage is within the above range, a sufficient ion implantation layer can be formed on the surface portion of the polyorganosiloxane layer, and the effects of the present invention can be further enhanced.

  As described above, when ions are implanted from the surface of the polyorganosiloxane layer formed on the base sheet 21, the surface portion of the polyorganosiloxane layer is modified, and an ion implantation layer is formed on the surface portion to form a gas barrier layer. 23 is obtained.

The thickness of the ion implantation layer can be controlled by the winding speed (line speed) of the base sheet 51a, the ion implantation processing time, the applied voltage, and the like.
In the present invention, the thickness of the ion implantation layer (gas barrier layer 23) formed in the polyorganosiloxane layer is usually 0.1 to 100 nm.

  As described above, after laminating the gas barrier layer 23 on one surface of the base sheet 21, the silane compound layer 22 is laminated on the gas barrier layer 23 as in the first embodiment, and the second embodiment shown in FIG. The protective sheet 20B having the form is obtained.

The protective sheet 20 </ b> B of the present embodiment adheres the other surface side (the opposite surface side of the silane compound layer 22) of the base material sheet 21 to the front surface side or the back surface side of the sealing material 30 of the solar cell module 50. It is used as a surface protection sheet for modules or a back surface protection sheet.
Since the protective sheet 20B according to the present embodiment does not contain halogen (F, Cl, Br, etc.) having a high environmental load, it is possible to suppress the generation of harmful substances when incinerated, and the environmental load is low. Further, the silane compound layer 22 is excellent in antifouling property, and further has excellent adhesion to the substrate sheet 21 side, and it is difficult to cause problems such as peeling off of the silane compound layer. The same effect as that of the protective sheet 20A is obtained, and further, the gas barrier layer 23 is laminated on one surface of the base sheet 21, whereby the protective sheet has excellent gas barrier properties and weather resistance.

FIG. 3 is a cross-sectional view showing a third embodiment of the protective sheet of the present invention.
In the protective sheet 20 </ b> C of the present embodiment, a gas barrier layer 23 is laminated on one surface of a base sheet 21, the silane compound layer 22 is laminated on the gas barrier layer 23, and further on the other surface of the base sheet 21. The adhesive layer 24 for adhering to the sealing material 30 of the solar cell module 50 via the laminating adhesive layer 25 is laminated.

  The adhesive layer 24 is an acrylic urethane resin from the viewpoint of improving the adhesion with the sealing material 30 of the solar cell module 50 when the protective sheet 20C is used as a surface protective sheet or a back surface protective sheet for a solar cell module. , An ethylene vinyl acetate copolymer (EVA), an ethylene-vinyl acetate copolymer, an ethylene-methacrylic acid copolymer, an ionomer resin in which molecules of the ethylene-methacrylic acid copolymer are crosslinked with metal ions, and the like. Furthermore, it is preferable to have thermal adhesiveness so that it can be thermally bonded to the sealing material 30. Here, thermal adhesiveness is a property that develops adhesiveness by heat treatment. As temperature in this heat processing, it is the range of 50-200 degreeC normally. From the viewpoint of having thermal adhesiveness, the adhesive layer 24 is selected from the group consisting of ethylene-vinyl acetate copolymer (EVA), ethylene-methacrylic acid copolymer (EMAA), ionomer resin, and mixtures thereof. One resin is preferable. In general, the sealing material 30 is often a sealing resin made of EVA. In this case, the sealing material 30 and the adhesive layer are formed by using the adhesive layer 24 made of a resin mainly composed of EVA. Adhesion with 24 can be improved.

  The thickness of the adhesive layer 24 is not particularly limited as long as the effects of the present invention are not impaired. More specifically, when the base resin of the adhesive layer 24 is EVA, the thickness is preferably in the range of 10 to 200 μm from the viewpoint of lightness and electrical insulation, and 20 to 150 μm. More preferably, it is the range.

Other polymers and various compounding agents may be added to the adhesive layer 24 as necessary.
As other polymers, soft polymers and other organic polymer fillers are used.
Moreover, as various compounding agents, any of an organic compound and an inorganic compound may be sufficient, and the compounding agent normally used in the resin industry is used. For example, anti-aging agents, stabilizers, pigments such as titanium dioxide, flame retardants, plasticizers, crystal nucleating agents, hydrochloric acid absorbers, antistatic agents, inorganic fillers, lubricants, antiblocking agents, and ultraviolet absorbers are used.

  The adhesive used as the material of the adhesive layer 25 for laminating used for bonding the base sheet 21 and the adhesive layer 24 is not particularly limited as long as the base sheet 21 and the adhesive layer 24 can be firmly bonded. Examples include acrylic adhesives, urethane adhesives, epoxy adhesives, silicone adhesives, and ester adhesives. These adhesives may be used individually by 1 type, and may be used in combination of 2 or more type.

The back sheet 20 </ b> C of the present embodiment adheres the adhesive layer 24 to the front surface side or the back surface side of the sealing material 30 of the solar cell module 50, and is used as a solar cell module surface protection sheet or a back surface protection sheet.
Since the protective sheet 20C of the present embodiment does not contain halogen (F, Cl, Br, etc.) with high environmental load, it can suppress the generation of harmful substances during incineration and has low environmental load. In addition, the silane compound layer 22 has excellent antifouling properties, and further has excellent adhesion to the base material sheet 21, and the protection of the first embodiment such that troubles such as peeling of the silane compound layer hardly occur. The protective sheet 20B according to the second embodiment has the same effect as the sheet 20A, and further has excellent gas barrier properties and weather resistance by laminating the gas barrier layer 23 on one surface of the base sheet 21. The same effect is obtained, and in addition, since the adhesive layer 24 is provided, the sheet can be firmly bonded and fixed to the front surface side or the back surface side of the sealing material 30 of the solar cell module 50. The solar cell module 50 excellent in property can be configured.

As shown in FIG. 4, the solar cell module of the present invention has the above-described protective sheets 20 </ b> A and 20 </ b> B such that the silane compound layer 22 is the outermost layer on the sealing material 30 on the front side or the back side of the solar cell module 50. , 20C.
The type and structure of the solar cell module 50 are not particularly limited, and examples thereof include amorphous silicon (a-Si) solar cells, single crystal silicon (c-Si) solar cells, microcrystalline silicon (μc-Si) solar cells, and GaAs. It can be set as a compound semiconductor type solar cell, a dye-sensitized solar cell, and an organic thin film solar cell.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited to a following example at all. In the examples and comparative examples, the thickness (film thickness) of each layer formed on the PET film as the base sheet is the stylus type step surface / shape measuring device (“XP-1” manufactured by Ambios Technology). It measured using.

Example 1 Polydimethylsiloxane (trade name “KS847H” manufactured by Shin-Etsu Chemical Co., Ltd., trade name) is formed to a thickness of 100 nm by a bar coating method on a white PET film having a thickness of 38 μm (trade name “Lumirror E20” manufactured by Toray Industries, Inc.) A film was formed and heat-cured at 120 ° C. for 1 minute, and ion implantation was performed on the obtained polyorganosiloxane layer under the following conditions to obtain a gas barrier layer. Thereafter, an inorganic polysilazane (perhydropolysilazane, manufactured by AZ Electronic Materials, trade name “AQUAMICA NP110”) was applied on the gas barrier layer by a bar coating method so as to have a dry film thickness of 100 nm, and dried at 120 ° C. for 5 minutes. Thereafter, a protective sheet of Example 1 was obtained.

(Ion implantation conditions)
・ Plasma generation gas (ion implantation gas): Argon ・ Gas flow rate: Argon 100 sccm
・ Repetition frequency: 1000Hz
-Applied voltage: -10 kV
・ Duty ratio: 0.5%
・ Pulse width: 5μsec
-Chamber internal pressure: 0.2 Pa
Processing time: 5 min.

[Example 2]
A protective sheet of Example 2 was obtained in the same manner as in Example 1 except that the plasma generation gas at the time of ion implantation was changed to nitrogen.

[Example 3]
A protective sheet of Example 3 was obtained in the same manner as in Example 1 except that the plasma generation gas at the time of ion implantation was changed to helium.

[Example 4]
A protective sheet of Example 4 was obtained in the same manner as in Example 1 except that the applied voltage at the time of ion implantation was changed to -15 kV.

[Example 5]
A protective sheet of Example 5 was obtained in the same manner as in Example 1 except that the applied voltage at the time of ion implantation was changed to -20 kV.

[Example 6]
A polyorganosiloxane layer having a thickness of 100 nm is provided on a transparent PET film having a thickness of 38 μm (trade name “Diafoil T100” manufactured by Mitsubishi Plastics Co., Ltd.). Otherwise, ion implantation is performed under the same conditions as in Example 1. The same inorganic polysilazane as used in Example 1 on the first sheet and the white PET film was applied by a bar coating method so that the dry film thickness was 100 nm, and dried at 120 ° C. for 5 minutes. A sheet of white PET film of the second sheet on the gas barrier layer of the first sheet so that the inorganic polysilazane layer becomes the outermost layer, polyester adhesive (AD-76P1 and CAT- manufactured by Toyo Ink Manufacturing Co., Ltd.) Bonding was performed using 10 L (curing agent) (mass ratio 100: 3), and the protective sheet of Example 6 was obtained.

[Example 7]
A protective sheet of Example 7 was obtained in the same manner as in Example 1 except that the silane compound layer was changed to organic polysilazane (trade name “tutoProm bright” manufactured by Clariant Japan Co., Ltd.).

[Example 8]
Example 8 A protective sheet was obtained.

[Example 9]
A protective sheet of Example 9 was obtained in the same manner as in Example 1 except that the organic silane layer was changed to polycarbosilane (trade name “Nypsi Type S”, manufactured by Nippon Carbon Co., Ltd., Mw = 4000).

[Example 10]
An inorganic polysilazane (similar to Example 1) was coated on a transparent PET film (trade name “Diafoil T100” manufactured by Mitsubishi Plastics, Inc.) by a bar coating method so that the dry film thickness was 100 nm, It dried for minutes and the protective sheet of Example 10 was obtained.

[Comparative Example 1]
Only a transparent PET film having a thickness of 38 μm (trade name “Diafoil T100” manufactured by Mitsubishi Plastics, Inc.) was used as the protective sheet of Comparative Example 1.

[Comparative Example 2]
223.2 parts by mass of a curable TFE copolymer (trade name “ZEFFLE GK570” manufactured by Daikin Industries, Ltd.), 250 parts by mass of titanium oxide as a white pigment (trade name “Ti-Pure R960” manufactured by DuPont), acetic acid After pre-mixing 126.8 parts by mass of butyl under stirring, 780 parts by mass of glass beads having a diameter of 1.2 mm were added and dispersed with a pigment disperser at 1500 rpm for 1 hour. Thereafter, the glass beads were filtered through a # 80 mesh sieve, and 269.2 parts by mass of a curable TFE copolymer (manufactured by Daikin Industries, Ltd., trade name “ZEFFLE GK570”) was added to the solution to prepare a white paint. .
On a transparent PET film (Mitsubishi Resin Co., Ltd., trade name “Diafoil T100”), the white paint was applied by a bar coating method so that the dry film thickness was 14 μm, and cured by heating at 80 ° C. for 30 minutes. The protective sheet of Example 2 was obtained.

[Comparative Example 3]
Only a PVF film (manufactured by DuPont, trade name “Tedlar TUB10AAH4”, thickness 25 μm) was used as a protective sheet of Comparative Example 3.

[Comparative Example 4]
On a transparent PET film having a thickness of 38 μm (trade name “Diafoil T100” manufactured by Mitsubishi Plastics Co., Ltd.), a SiO ₂ film having a thickness of 50 nm was formed using a magnetron sputtering method. Obtained.

[Comparative Example 5]
The white coating material prepared in Comparative Example 2 was applied to the film-forming surface of the sheet obtained in Comparative Example 4 by a bar coating method so that the dry film thickness was 14 μm, and heated and cured at 80 ° C. for 30 minutes. Comparative Example 5 A protective sheet was obtained.

For each protective sheet of Examples 1 to 10 and Comparative Examples 1 to 5 prepared as described above, water vapor permeability, presence or absence of cracks after bending test, adhesion, reflectance, and antifouling test are measured. Went.
These measurements were performed as follows. The measurement results are summarized in Table 1.

<Water vapor permeability>
In accordance with the standard of ISO 15106-1: 2003, a water vapor transmission meter (manufactured by LYSSY, device name: L80-5000) is used by a moisture sensitive sensor method under the conditions of a temperature of a transmission cell of 40 ° C. and a relative humidity difference of 90%. Measured.

<Presence of cracks after bending test>
A protective sheet (15 cm x 35 cm) is wound around a stainless steel rod with a diameter of 3 mm and a length of 20 cm so that the surface without the gas barrier layer is in contact with it. : IMC-15AE), and was reciprocated 10 minutes for 1 minute while applying a load of 1.2 kg to the protective sheet. The moving distance of the protective sheet was 20 cm per round trip. The bending test was performed in an environment of 23 ° C. and relative humidity of 50%.
The protective sheet after the bending test was observed with an optical microscope (manufactured by Keyence Corporation, apparatus name: VHX-100) at a magnification of 2000 times to examine the presence or absence of cracks in the gas barrier layer. As the evaluation criteria, the case where no crack was observed was evaluated as ◯, and the case where a crack was present was evaluated as ×. However, since the gas barrier layer is not provided in Comparative Examples 1 and 3, measurement is not performed.

<Adhesion evaluation>
In accordance with JIS K5600-5-6, 10 × 10 square grids of 1 mm squares were produced on the surface of the protective layer of each of the produced protective sheets of Examples 1 to 10 and Comparative Examples 1 to 5, and cellophane tape (Nichiban) Company: CT24) was affixed and evaluated by the degree of peeling of the film-forming layer when the tape was peeled off. Judgment was expressed by the total number of the squares that were completely peeled out of 100 squares and the number of squares that were partially peeled off at the edge or the like, and evaluated according to the following criteria.
0: 0 cell 1: 1 to 5 cell 2: 6 to 14 cell 3:15 to 34 cell 4:35 to 64 cell 5:65 cell or more However, Comparative Examples 1, 3 and 4 are film formation layers to be evaluated for peeling. Because there is no, measurement is not performed.

<Reflectance>
The reflectance (%) at a wavelength of 550 nm of each protective sheet was measured using an ultraviolet-visible near-infrared spectrophotometer (manufactured by Shimadzu Corporation, apparatus name: UV-3600).

<Anti-fouling test>
For each of the protective sheets of Examples 1 to 10 and Comparative Examples 1 to 5 prepared as described above, an aqueous black ink (manufactured by Zebra Co., Ltd., trade name “Paper Mackie Extra Fine WYTS5-BK”), oily black ink (Zebra Co., Ltd., trade name “Mackie Extra Fine MO-120-MC-BK”) was attached, washed for 24 hours and then washed with water, then with a soft cloth (Asahi Kasei Co., Ltd., trade name “BEMCOT M-3”) It wiped off and washed, and the antifouling property was evaluated according to the following criteria.
○: Dirt is removed ×: Dirt is not removed

Since all of the protective sheets of Examples 1 to 10 according to the present invention do not contain halogen (F, Cl, Br, etc.) with high environmental load, it is possible to suppress the generation of harmful substances when incinerated. The load will be low.
Moreover, the protective sheet of Examples 1-10 was excellent in antifouling property.
Furthermore, the protective sheets of Examples 1 to 10 are excellent in adhesion between the PET film as the base sheet and the silane compound layer, and no cracks are generated in the silane compound layer even after the bending test. Defects such as peeling are unlikely to occur.
Moreover, the protective sheet of Examples 1-9 which laminated | stacked the gas barrier layer and the silane compound layer in order on PET film was excellent in the bad stage compared with the protective sheet of the comparative example 2 provided with the conventional fluororesin coat layer. It had water vapor barrier properties.

  The protective sheet of the present invention does not contain halogen such as fluorine, can be incinerated at the time of disposal, has a low environmental load, and is excellent in adhesion to the base sheet and weather resistance. Therefore, the solar cell module constructed by adhering the protective sheet of the present invention has weather resistance and durability equal to or higher than those of the conventional protective sheet having a fluororesin layer, and the protective sheet is disposed at the time of disposal. It can be incinerated and has a low environmental impact.

DESCRIPTION OF SYMBOLS 10 Surface protection sheet 20 Back surface protection sheet 20A, 20B, 20C Protection sheet 21 Base material sheet 22 Silane compound layer 23 Gas barrier layer 24 Adhesive layer 25 Adhesive layer for laminating 30 Sealing material 40 Solar cell 50 Solar cell module

Claims (8)

  A protective sheet for a solar cell module, comprising a base sheet and an outermost silane compound layer laminated on the base sheet.   The protective sheet for a solar cell module according to claim 1, wherein a gas barrier layer is laminated on the base sheet.   The said silane compound layer consists of 1 type, or 2 or more types of silane compounds selected from the group which consists of organic polysilazane, inorganic polysilazane, polycarbosilane, polysilane, and polyorganosiloxane. The protective sheet for solar cell modules of description.   The protective sheet for a solar cell module according to claim 2 or 3, wherein the gas barrier layer is obtained by ion implantation of the polyorganosiloxane layer. The ions implanted into the polyorganosiloxane layer are generated from one or more gases selected from the group consisting of H ₂ , He, N ₂ , O ₂ , Ne, Ar, Kr, and Xe. The protective sheet for solar cell modules of Claim 4 characterized by these.   The pigment is added in the said base material sheet, The protective sheet for solar cell modules in any one of Claims 1-5 characterized by the above-mentioned.   It consists of material which does not contain a halogen, The protection sheet for solar cell modules in any one of Claims 1-6 characterized by the above-mentioned.   The solar cell module formed by adhere | attaching the protection sheet for solar cell modules of any one of Claims 1-7 on one or both of the surface and a back surface.

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