JP2009099805A - Hot-melt type member for organic thin film solar cell and organic thin film solar cell case sealing panel - Google Patents

Abstract

An organic thin film solar cell element capable of maintaining stable solar cell characteristics (photoelectric conversion characteristics) without being affected by moisture and oxygen over a long period of time.
An organic thin film solar cell element casing sealing panel including 1) a substrate, 2) an organic thin film solar cell element formed on the substrate, and 3) a casing for sealing the organic thin film solar cell element. An organic thin film solar cell element casing sealing panel in which a hot melt type member containing a moisture scavenger and wax is disposed between the organic thin film solar cell element and the casing.
[Selection figure] None

Description

  The present invention relates to a hot melt type member and an organic thin film solar cell element casing sealing panel. In particular, the present invention relates to an improved technology that enables mass production of an organic thin-film solar cell element casing sealing panel that can maintain stable power generation characteristics without being affected by moisture and oxygen over a long period of time.

The mainstream silicon-based solar cells currently have high photoelectric conversion efficiency, but they have a large environmental impact in terms of resources, carbon dioxide emissions during production, costs, etc. Therefore, organic thin film solar cells have been studied worldwide as solar cells that are cleaner and have less resource constraints. However, the organic thin-film solar cell at the present stage has not yet reached the practical stage because of its low photoelectric conversion efficiency and short lifetime. Maximum value of the organic thin-film solar cells currently reported, in tandem cells using co-evaporation of CuPc and C ₆₀ to Forrest et al. Produced in 2004, a photoelectric change Efficiency 5.7% (Non-patent Reference 1). In 2005, Heeger et al. Achieved a photoelectric conversion efficiency of 5% in an ITO / PEDOT: PSS / P3HT: PCBM blend film / Al type cell (Non-patent Document 2).

  The organic thin film solar cell element is configured, for example, by forming an ITO (Indium Tin Oxide) transparent electrode (anode), an organic film (photoelectric conversion layer), and a metal electrode (cathode) on a glass substrate. In an organic thin film solar cell element, an organic film or a metal electrode is known to be weak against moisture, oxygen, heat, or an organic gas generated from a component (hereinafter also referred to as “outgas”). In order to extend the life of the battery element, the organic thin film solar cell element is placed in an atmosphere excluding moisture and oxygen, the outgas from the components is reduced as much as possible, and the heat generated when the organic thin film solar cell element is driven It is necessary to prevent deterioration due to moisture, oxygen, heat, and outgas by adopting a structure that can efficiently escape.

  Specifically, an organic thin film solar cell element (anode 2, organic layer 3, cathode 4) is laminated on a substrate 1 such as glass as shown in FIG. A sealing cap 5 made of glass, metal or the like is placed on the substrate 1 and sealed with a sealing agent 6, and the organic thin-film solar cell element is sealed in a sealed container constituted by the substrate 1 and the sealing cap 5. . And in this sealed container, the method of enclosing barium oxide (BaO), calcium oxide (CaO) for capturing moisture, or a sheet-like moisture scavenger 7 using these is adopted.

As an electronic device using such a moisture scavenger, for example, a transparent electrode formed of a transparent electrode material on a transparent substrate surface, a light emitting layer made of an EL material laminated on the transparent electrode, and the light emitting layer A back electrode formed opposite to the transparent electrode, a water repellent film covering the entire surface of the light emitting layer and the back electrode, and an insulating protection for sealing the light emitting layer together with the water repellent film An organic EL display panel characterized by comprising members is known (Patent Document 1).
Jiangeng Xue, Soichi Uchida, Barry P. Rand, Stephen R. Forrest, Appl. Phys. Lett., Vol. 85. No. 23, 6 December 2004 Wanli Ma, Cuiying Yang, Xiong Gong, Kwaghee Lee, Alan J. Heeger, Adv. Funct. Mater. 15, 1617-1622 (2005) JP 2000-68047 A

  The aspect which applied the organic electroluminescent display panel described in patent document 1 to the organic thin-film solar cell element housing sealing panel is demonstrated using FIG. In FIG. 1, a powder cap BaO or CaO that is a moisture trapping agent or a sheet-like moisture trapping agent 7 using these is provided on a sealing cap 5 that seals the organic thin film solar cell element on the substrate 1. ing. Here, when the required amount of the moisture scavenger is filled in the sealing cap 5, the thickness is at least about 0.2 mm, so that the recess depth of the sealing cap 5 is 0.3 to 0.5 mm. Is necessary. Therefore, the thickness of the sealing cap 5 is required to be 0.7 to 1.0 mm, and there is a problem that the thickness of the organic thin film solar cell element casing sealing panel is increased.

  Moreover, in the organic thin film solar cell element casing sealing panel using the sealing cap 5, when the size of the organic layer is increased, since the sealed container has a hollow structure, the organic thin film solar cell element casing sealing panel There is a problem that the strength is lowered or the sealing cap 5 is easily bent and may come into contact with the cathode, and the reliability as a photoelectric conversion element is lowered.

  As an example of thin film coating with a transparent moisture absorbing material (organic moisture scavenger), Auredry (Futaba Electronics Co., Ltd.) is known. However, this thin film has a physical problem that it gradually cracks (cracks) as the amount of moisture absorbed increases and damages the organic thin film solar cell element. Also, because of the special liquid, special coating technology is required.

  Furthermore, Patent Document 1 prevents the adhesion of moisture by forming a water repellent film composed of a single component such as wax, fluorine-based water repellent, silicon-based water repellent on the organic EL element, The purpose is to prevent the deterioration of the organic EL element. When used in combination with a water scavenger, the formation of a water scavenger layer is mainly performed by using particles having a relatively large particle diameter of 100 to 500 μm, or by sprinkling the particles after forming a water-repellent film. It is not what I did. Thus, in patent document 1, it is not examined about the organic thin-film solar cell element housing sealing panel which uses a moisture scavenger together and is thin.

  Moreover, in the said patent document 1, since the comparatively big moisture scavenger with a particle diameter of 100-500 micrometers is used with a powder, there exists a problem that it cannot be used in an actual process. Moreover, in Patent Document 1, since the water repellent layer is formed by vapor deposition of wax, depending on the wax used, the performance of the organic EL element may be degraded by the evaporated wax.

  Accordingly, the main object of the present invention is to overcome the above-mentioned problems, and in particular, the organic thin-film solar cell element casing that can maintain stable light emission characteristics without being affected by moisture and oxygen over a long period of time. It is to provide a stop panel.

  As a result of repeated studies in view of the problems of the prior art, the present inventor has found that a member having a specific composition can achieve the above object, and has completed the present invention.

That is, this invention relates to the following hot-melt type member and organic thin-film solar cell element housing sealing panel.
1. A hot-melt type member for organic thin-film solar cells comprising a moisture scavenger and a wax.
2. Item 2. The hot melt type member according to Item 1, wherein the moisture scavenger is 1) an organometallic compound and / or 2) a powdered inorganic oxide having an average particle size of 90 µm or less.
3. Item 3. The hot melt type member according to Item 1 or 2, wherein a moisture scavenger is contained in the hot melt type member in an amount of 50 to 99% by weight.
4). Item 4. The hot melt member according to any one of Items 1 to 3, wherein a wax is contained in the hot melt member in an amount of 1 to 50% by weight.
5). Item 5. The hot melt member according to any one of Items 1 to 4, wherein the weight loss after drying under reduced pressure at 150 ° C for 4 hours under vacuum is 0.1% or less.
6). Item 6. The hot melt member according to any one of Items 1 to 5, wherein the hot melt member has a thickness of 100 µm or less.
7). Item 7. The hot-melt member according to any one of Items 1 to 6, which is used inside the casing of the organic thin-film solar cell element sealed with the casing.
8). The transfer film which laminated | stacked the hot-melt-type member in any one of said claim | item 1-7 on the releasable base material.
9.1) a substrate, 2) an organic thin film solar cell element formed on the substrate, and 3) an organic thin film solar cell housing sealing panel including a housing for sealing the organic thin film solar cell element, The organic thin-film solar cell element housing sealing panel in which the hot-melt type member according to any one of Items 1 to 7 is disposed between the organic thin-film solar cell element and the housing.
10. The organic thin-film solar cell housing sealing panel according to Item 9, wherein substantially all of the space between the organic thin-film solar cell device and the housing is occupied by the hot-melt member.
11. It is obtained by arranging a plurality of the hot-melt type members on the organic thin-film solar cell element or the casing, and bonding the organic thin-film solar cell element and the casing through the hot-melt type member. Item 11. The organic thin-film solar cell element housing sealing panel according to Item 10 above.
12 The sealing member which laminated | stacked the hot-melt type member in any one of said item 1-7 on the housing | casing.
13.1) Substrate, 2) Organic thin film solar cell element formed on the substrate, and 3) Method for producing organic thin film solar cell casing sealing panel including casing for sealing the organic thin film solar cell element The plurality of hot melt members according to any one of Items 1 to 7 are arranged side by side on the organic thin film solar cell element or the casing, and the organic thin film solar cell element and the casing are arranged. The manufacturing method which has the process of bonding together through the said hot-melt type member.
14 In the above item 13, the organic thin film solar cell element and the casing are bonded so that the entire space between the organic thin film solar cell element and the casing is substantially occupied by the hot-melt member. The manufacturing method as described.

  Since the hot-melt member of the present invention has hot-melt properties, it can be arranged in any thickness and pattern on the housing (hereinafter also referred to as “sealing housing”) or on the organic thin-film solar cell element. . Therefore, by bonding the organic thin-film solar cell element and the sealing housing through the hot-melt type member, a hot-melt type member layer containing a moisture trapping agent that is in close contact with the organic thin-film solar cell element and has no space is formed. It can be formed. Moreover, since generation | occurrence | production of outgas is also suppressed, it can provide the organic thin-film solar cell element housing sealing panel which does not have the influence of a water | moisture content, oxygen, and outgas over a long term, and maintains the stable photoelectric conversion characteristic.

  In particular, unlike the case where the organic moisture scavenger is used alone, the hot melt type member of the present invention can alleviate or eliminate problems such as cracks. In this respect as well, it is possible to contribute to the long-term stability of the photoelectric conversion characteristics.

  As a preferred form, powdered inorganic oxides or organometallic compounds (including organometallic complexes, such as BaO and CaO) having a small particle size, or a sheet-like (thin film) hot-melt type using these. In order to use a member, it is not necessary to use a thick sealing cap (sealing housing) 5 having a recess, and a flat thin plate-shaped sealing plate can be used as a sealing casing.

  Further, as a more preferable form, the entire space between the organic thin film solar cell element and the sealing housing is substantially occupied by the hot-melt type member, so that the organic thin film solar cell device housing is sealed. The thickness of the panel can be reduced, and it is possible to cope with an increase in size without problems.

1. Hot Melt Type Member The hot melt type member of the present invention is characterized by containing a moisture scavenger (hereinafter also referred to as “moisture getter agent”) and wax.
(Moisture scavenger)
The moisture trapping agent may be either an inorganic moisture trapping agent or an organic moisture trapping agent as long as it is known as a so-called moisture trapping agent, and is not particularly limited. For example, in addition to powdered inorganic oxides such as barium oxide (BaO), calcium oxide (CaO), and strontium oxide (SrO), organometallic compounds known as transparent moisture getter agents can be used. These moisture scavengers can be used alone or in combination of two or more. A commercial item can also be used for these moisture scavengers.

  In addition, when using a powder-form moisture scavenger as in the case of the powdered inorganic oxide, the average particle diameter may be usually within a range of less than 100 μm, preferably 90 μm or less, more preferably 50 μm or less, Preferably, it may be 0.01 μm or more and 10 μm or less. If the average particle diameter is less than 100 μm, the possibility of damaging the organic thin film solar cell element is reduced, and when the organic thin film solar cell element casing sealing panel is manufactured, a recess is formed in the sealing casing. There is no need to provide it. When the particle diameter is less than 0.01 μm, the particles may be scattered or the particle production cost may be increased.

  Among these moisture scavengers, in the present invention, it is desirable to use 1) an organometallic compound and / or 2) a powdered inorganic oxide having an average particle size of 90 μm or less. In particular, from the viewpoint of mixing with a wax and adhesion to an organic thin film solar cell element or the like, an organometallic compound that dissolves in the same solvent as the wax is preferable as a moisture scavenger. In order to make sunlight reach the organic layer efficiently, it is preferable to use a transparent moisture scavenger, and examples thereof include organic metal compounds in addition to fine powder having a particle size of 100 nm or less. As the organometallic compound, organometallic compounds described in JP-A-2005-298598 can be suitably used.

The content of the water scavenger can be appropriately set according to the type of the water scavenger to be used, etc., but is usually about 50 to 99% by weight, particularly 80 to 99% by weight in the hot melt type member of the present invention. preferable. If the content of the moisture scavenger is less than 50% by weight, the moisture trapping performance may be insufficient, and if it exceeds 99% by weight, the adhesion / adhesiveness of the hot-melt type member to the organic thin film solar cell element may be reduced. In addition, the retention of the moisture scavenger may be reduced.
(wax)
The wax is not limited as long as it can impart a hot melt function to the hot melt type member of the present invention, and can be appropriately selected from known or commercially available waxes. For example, paraffin wax, microcrystalline wax or the like can be used. These may be used alone or in combination of two or more. These waxes preferably have a melting point of 60 to 100 ° C. from the standpoint of the production process and the like. If the melting point of the wax is lower than 60 ° C, the organic thin film solar cell element may be dissolved and swollen. If the melting point exceeds 100 ° C, heat of 100 ° C or higher is required when softening or melting the hot-melt type member. Further, there is a possibility that heat of 100 ° C. or higher is applied to the organic thin film solar cell element, and there is a possibility that the organic matter is degraded.

  Further, in the present invention, in particular, it is possible to prevent the occurrence of outgas having an adverse effect on the organic thin film solar cell element, and it is excellent in adhesion with a substrate such as a glass substrate, a sealing housing, and the organic thin film solar cell element. It is preferable to use crystallin wax.

  The content of the wax can be appropriately set according to the type of wax to be used and the like, but is usually about 1 to 50% by weight, particularly preferably 1 to 10% by weight in the hot melt type member of the present invention. When the content of the wax exceeds 50% by weight, the moisture trapping property may be insufficient. Moreover, when it is less than 1% by weight, there is a risk that the effect of suppressing cracks with time due to moisture trapping when using an organic metal compound as a moisture trapping agent may deteriorate. is there. From the viewpoint of a transparent hot melt type member, the amount of wax in the hot melt type member is preferably 10% by weight or less.

Moreover, in order to make sunlight reach | attain an organic layer efficiently, it is preferable to use transparent wax. In addition, the blending amount of the wax in the hot melt type member or the thickness of the layer obtained using the hot melt type member may be reduced.
(Hot melt type member)
The hot-melt type member of the present invention may be a two-component system of the above-described moisture scavenger and wax, but may contain various additives as necessary as other components.

  The shape of the hot melt type member of the present invention is not limited, and the shape can be adopted according to a desired application. For example, any of a thin film shape, a plate shape, an indefinite shape, and the like may be used. In particular, in the present invention, it is preferably used as a thin film. Although the thickness in this case is not limited, it is generally preferably 100 μm or less, particularly about 5 to 50 μm.

  The hot melt type member of the present invention is usually solid and used as a member for an organic thin film solar cell element after drying (solvent dilution type) or after cooling (no solvent type). In addition, it may be used in a viscous state at the time of use such as a laminating operation on a sealing housing, a releasable base material or the like. That is, it can be used by being softened or melted by heating at the time of use, or dissolved in an organic solvent. For this reason, since the hot-melt type member of the present invention can be adhered and laminated on an organic thin film solar cell element, a casing for sealing, etc., the moisture scavenger is adhered to the organic thin film solar cell element and sealed. The organic thin film solar cell element and the like can be protected from the moisture that has penetrated into the container, the moisture contained in the organic thin film solar cell element and the like, and outgas. In addition, when the organic thin-film solar cell element casing sealing panel is irradiated with sunlight as a solar cell, the hot-melt member may be in a liquid state.

  When it is softened or melted by heating at the time of use for adhesion or coating, it is heated until it is softened or melted, and the hot melt type member is adhered or coated on a substrate (organic thin film solar cell element laminated surface), a sealing housing, etc. By doing so, it is possible to form the member in a desired shape such as a thin film. Further, in the case of the thin film hot melt type member as described above, if a part is softened or melted, it can be adhered (fused) to a substrate or the like.

  For example, when a thin film is formed by coating (coating), for example, the method of softening or melting by heating can be used to efficiently obtain the thin film by heating the coating head to about 70 to 80 ° C. In addition, since the drying time after coating can be shortened, productivity can be further increased, and the risk of outgas generation is also reduced.

From the viewpoint of suppressing the generation of outgas, the following solvent-free hot-melt type member is used for softening and melting by heating, and stacking work on an organic thin film solar cell element, a sealing housing, or the like is preferable.
(Transfer film)
In particular, in the present invention, a laminate in which a thin hot-melt member is laminated on a releasable substrate (release film) is preferable because it can be used as a transfer film. In other words, if used as a transfer film, it is necessary to stock it as a transfer film when producing electronic devices such as organic thin-film solar cell element housing sealing panels, organic EL lighting panels, organic EL display panels, and organic semiconductors. When the transfer film is taken out and the hot melt type member on the releasable substrate is transferred from the releasable substrate to the electronic device side such as an organic thin film solar cell element, the above-mentioned member can be easily removed It can be attached to an electronic device such as a battery element.

  The thickness of the hot-melt member on the release film is preferably 100 μm or less, particularly about 5 to 50 μm.

  As the releasable substrate, a known or commercially available substrate can be used, but preferably, an alkyd type release agent is applied on a resin film. Moreover, the hot melt type member on the release film may be transferred from the releasable base material to the sealing case and used as the sealing member.

  The transfer film is produced by applying a liquid hot-melt type member dissolved by heating or using an organic solvent on the releasable substrate, and volatilizing the organic solvent by cooling or heating, thereby releasing the releasable substrate. A thin film hot melt type member can be laminated thereon.

  When storing the transfer film in roll form, a cover film may be laminated on the hot melt mold member on the release film so that the hot melt mold member does not stick to the back surface of the release film. Good. As the cover film, a film made of polyethylene, polypropylene, polycarbonate, polyester, or the like can be used. More preferably, the surface of the cover film that is in contact with the hot melt type member has a slight adhesiveness. Specifically, if a film with adhesive or a cover film with a small amount of adhesive residue is used, it is possible to prevent misalignment when the transfer film and the cover film are bonded, and to transfer during storage or transportation. It is preferable from a viewpoint of prevention of deviation between the film and the cover film.

  The transfer film and the cover film may be bonded by tangential bonding in which the film is bonded in the tangential direction while being pressed with a rubber roll or the like.

  The transfer film has a three-layer structure of a release sheet, a hot melt type member, and a cover film, and is preferably wound into a roll and stored, transported, or the like.

  In addition, when storing and / or transporting a transfer film (regardless of the presence or absence of a cover film) from the atmosphere such as a glove box substituted with nitrogen gas to the atmosphere, the transfer film has a gas barrier property. It is preferable that it is hermetically sealed and packaged, and for example, hermetically packaged in a nitrogen-substituted bag made of an aluminum foil film (a laminate of an aluminum foil and a polyester film) is preferable.

  When transferring the hot-melt type member to a sealing housing or an organic thin-film solar cell element, the transfer sheet wrapped in a glove box substituted with nitrogen gas is put again and the transfer operation is performed.

Lamination of a hot-melt type member on a releasable substrate, lamination of a cover film, and hermetic packaging are performed in a nitrogen gas atmosphere in which oxygen is not present or in a vacuum.
(Method for producing hot melt type member)
In the method for producing a hot melt type member of the present invention, a water scavenger, wax, and other additives may be mixed uniformly as required. As a mixing method, an organic solvent such as heptane or triethanolamine can be added and mixed, or heating can be performed without using the organic solvent, and the wax can be melted and mixed. From the viewpoint of mixing, it is preferable to mix using a solvent that dissolves both the moisture scavenger and the wax.

  As a mixer, well-known mixing apparatuses or kneading apparatuses, such as a stirrer and a kneader, can be used, for example. After mixing each component uniformly, it can shape | mold into a desired shape as needed.

  It is desirable to remove the solvent component by heating and drying the hot melt type member of the present invention after mixing. The degree of removal is preferably set to a level at which the weight loss after drying the above member under reduced pressure at 150 ° C. for 4 hours is 0.1% or less. That is, a hot-melt type member having a weight loss of 0.1% or less after drying under reduced pressure at 150 ° C. for 4 hours under vacuum is more preferable as the hot-melt type member (solvent-free hot-melt type member) of the present invention. When the weight reduction after drying under reduced pressure exceeds 0.1%, when used for an organic thin film solar cell element casing sealing panel, outgas is generated and the organic thin film solar cell element may be deteriorated.

  The hot melt type member of the present invention can be suitably used particularly for an organic thin film solar cell element. More specifically, the hot melt type member is used inside the casing of the organic thin film solar cell element sealed with the casing. The hot melt type member of the present invention is a mixture of a so-called moisture scavenger and wax, and the organic thin film solar cell element is sealed in a sealed container of an electronic device such as an organic thin film solar cell housing sealing panel. In addition to being used as a sealing material, it can also be used as an adhesive material for assembling and fixing components such as a substrate constituting a sealed container. It also functions as a moisture trapping agent that adsorbs moisture that has entered the sealed container, moisture contained in the organic thin film solar cell element, and the like. The hot melt type member of the present invention is a multifunctional material having both of these functions.

2. TECHNICAL FIELD The present invention relates to 1) a substrate, 2) an organic thin film solar cell element formed on the substrate, and 3) a housing (member) for sealing the organic thin film solar cell element. An organic thin-film solar cell element casing sealing panel comprising a hot-melt type member of the present invention disposed between the organic thin-film solar cell element and the casing. Includes stop panels.

  In addition, in this invention, a substrate means the glass plate etc. for forming an organic thin film solar cell element. The organic thin film solar cell element refers to a laminate formed by sandwiching at least an organic layer (organic photoelectric conversion layer) between an anode and a cathode. In the present invention, the casing may be any member that can seal the organic thin film solar cell element from the outside air, and may be any of a box type, a plate type, and the like, and the shape is not particularly limited. From the viewpoint of reducing the thickness of the obtained organic thin-film solar cell element casing sealing panel, a flat thin glass plate is preferable.

  In the organic thin film solar cell element sealing panel of the present invention, the hot melt type member is disposed between the organic thin film solar cell element and the sealing casing. Moreover, the organic thin film solar cell element can employ | adopt the structure and structure similar to a well-known organic thin film solar cell element. Therefore, basically, the hot-melt type member of the present invention can be used in organic thin-film solar cell casing encapsulating panels of all structures conventionally known.

  The hot melt type member of the present invention can be obtained by mixing and stirring the wax and the moisture scavenger described above. Specific examples of the organic thin film solar cell case sealing panel using this hot melt type member The structure will be described with reference to FIG.

  In FIG. 2, an anode 2, an organic layer 3, and a cathode 4 are stacked as an organic thin film solar cell element on a substrate 1, and a short prevention layer 8 is further stacked. Further, on the organic thin film solar cell element, a hot-melt type member 9 in which a moisture scavenger is added to wax is provided as an adhesive layer, which is solidified to adhere the sealing casing 10.

  In the present invention, an anti-shorting layer can be provided as necessary. The short prevention layer is formed to prevent a short circuit between the cathode and the anode, and is made of an inorganic material such as silicon oxide, aluminum oxide, silicon nitride, silicon carbide, or an organic material such as polyparaxylene. Can be used. In the present invention, a short prevention layer (polyparaxylene-based insulating layer) made of polyparaxylene is particularly preferable.

  The polyparaxylene-based insulating layer is composed of polyparaxylene and / or a derivative thereof. The derivative is not limited as long as it has para-xylene as a basic unit, and a known or commercially available derivative can be used. Preferable commercially available products include, for example, product names “diX C”, “diX D”, “diX F”, “diX N” (all are products from Daisei Kasei Co., Ltd.).

  The polyparaxylene-based insulating layer is formed on at least the cathode. In this case, the polyparaxylene derivative layer may be formed so as to cover at least the upper surface of the cathode. In particular, it is desirable to form a polyparaxylene-based insulating layer so as to cover the upper surface and side surfaces of the cathode. That is, it is desirable to form the polyparasylene-based insulating layer so as to cover all the cathode. In addition, a polyparaxylene-based insulating layer can be formed so as to cover all of the cathode and the organic layer (organic photoelectric conversion layer).

  The thickness of the polyparasylene-based insulating layer can be appropriately set according to the type of polyparasylene or a derivative thereof used, the type and type of the organic thin film solar cell element, etc. The thickness is preferably 900 nm. By setting to such a range, it is possible to effectively prevent the occurrence of a short circuit, and as a result, the lifetime of the element can be extended.

  The method for forming the polyparaxylene-based insulating layer is not particularly limited as long as the above configuration can be formed, and any of a gas phase method, a liquid phase method, and a solid phase method can be employed. For example, a method of forming by a vapor phase method using a raw material (for example, paraxylene (monomer) and / or paraxylene oligomer) for forming a polyparaxylene insulating layer is preferable. That is, in the present invention, a polyparaxylene insulating layer formed by a vapor phase method using a raw material of a polyparaxylene derivative (for example, paraxylene (monomer) and / or paraxylene oligomer) is used as the polyparaxylene-based insulating layer. preferable. In particular, a polyparaxylene insulating layer formed by a vapor phase method using paraxylene oligomer (preferably paraxylene dimer) as a raw material is more preferable.

  As the vapor phase method, for example, a CVD method, a PVD method, or the like can be adopted. Among these, the CVD method, particularly the thermal CVD method can be preferably employed. The thermal decomposition temperature condition in this case is preferably about 600 to 700 ° C. The atmosphere is preferably a vacuum atmosphere of 1.0 Pa or less. The deposition rate may be about 1-2 nm / min. The thermal CVD method can be performed using a known or commercially available apparatus.

  In addition, a well-known or commercially available product can be used for the said raw material or polyparaxylene or its derivative (s).

  A UV curable sealant 6 is provided around the hot melt member to be solidified. The sealant provided around the hot melt type member is not limited to the UV curable sealant, and a known sealant such as a thermosetting epoxy sealant, a sheet-like adhesive film, and a low melting glass powder paste is also used. be able to.

  The hot melt type member is directly applied to the sealing casing 10 or transferred to the sealing casing 10 using a transfer film applied in a sheet form (thin film shape) on the release film, and the organic thin film solar cell element is transferred to the sealing casing 10. A thin organic thin film solar cell that can be mass-produced with high reliability by vacuum bonding the laminated substrate 1 (the surface on which the organic thin film solar cell element of the substrate is formed) and the hot melt type member on the sealing casing. An element housing sealing panel can be manufactured. Also, the hot-melt type member is transferred onto the organic thin-film solar cell element using a transfer film applied directly on the organic thin-film solar cell element or in a sheet form (thin film shape) on the release film, and sealed. The organic thin film solar cell casing sealing panel can also be manufactured by vacuum bonding the housing for use with the hot melt type member on the organic thin film solar cell element.

  Further, as shown in FIG. 2, in the case of this structure, an appropriate amount of hot melt type member is applied on the sealing casing 10, or a thin hot melt type member on the release film is transferred, and further organic The hot-melt type member covers the organic thin film solar cell element by vacuum bonding with the thin film solar cell element so that no space is generated between the organic thin film solar cell element and the sealing casing 10 (for example, a glass plate). You can also. That is, it is desirable that the entire space between the organic thin film solar cell element and the housing is substantially occupied by the hot melt type member. The hot melt type member is disposed in close contact with the organic thin film solar cell element between the substrate and the sealing housing 10 without any gap, thereby allowing contact between moisture, oxygen, outgas and the organic thin film solar cell element. The strength of the organic thin-film solar cell housing sealing panel can be increased. At this time, in order to improve adhesion, a glass plate or the like used as a sealing housing is heated and vacuum bonded. Furthermore, if a UV curable sealant (epoxy sealant) is provided around the hot melt type member and solidified, the sealed state of the organic thin film solar cell element can be further improved.

  An organic thin film solar cell casing sealing panel in which the entire space between the organic thin film solar cell element and the casing is substantially occupied by the hot melt type member is a single (film-like) hot melt type member Can be obtained by laminating the organic thin film solar cell element and the casing (via a hot-melt type member). When obtaining an arbitrary size, for example, a large-sized organic thin film solar cell casing sealing panel, the film made of the hot melt type member of the present invention is spaced on the casing or the organic thin film solar cell element. After bonding together, the housing and the organic thin film solar cell element are bonded together via a hot melt type member, so that substantially all of the space between the case and the organic thin film solar cell element is hot melt type member. The organic thin-film solar cell element casing sealing panel occupied by is easily obtained. In other words, a plurality of (film-like) hot-melt type members are arranged side by side on an organic thin-film solar cell element or casing, and the organic thin-film solar cell element and the casing are bonded together via the hot-melt type member. An organic thin-film solar cell casing sealing panel in which the entire space between the thin-film solar cell element and the casing is substantially occupied by the hot-melt type member can be easily obtained.

  The interval (the gap between the films) in which the films made of the hot melt type members are laminated and bonded depends on the thickness of the film made of the hot melt type members, but is preferably 10 mm or less. More preferably, it is 3 mm or less. If it exceeds 10 mm, the entire space between the housing and the organic thin-film solar cell element may not be occupied by the hot melt type member. Moreover, the lower limit of the space | interval which bonds the film which consists of a hot-melt-type member side by side is so preferable that it is small.

  In the present invention, the hot-melt type member is softened by the heat treatment at the time of bonding the casing and the organic thin-film solar cell element, and the gap between the hot-melt type members bonded together with a gap therebetween is softened. Can be filled with.

  Thus, by using a plurality of films made of hot melt type members, a large-area organic thin film solar cell element can be easily sealed.

  In addition, the film consisting of a hot melt type member is preferably a thin film hot melt type member formed using the transfer film of the present invention.

  The hot melt type member and organic thin film solar cell element housing sealing panel of the present invention will be described with reference to examples and comparative examples. However, the present invention is not limited to the examples. For example, the size of the hot melt type member is not limited to the size described in the examples, and 10 mm × 10 mm to 1000 mm × 1000 mm and other sizes of 10 mm × 10 mm or less or 1000 mm × 1000 mm or more are produced, Can be used.

As shown in FIG. 2, the organic thin film solar cell element sealing panel produced in the examples and comparative examples has an ITO transparent electrode 2 as an anode formed on a substrate 1, and an organic film on the transparent electrode 2. 3 (organic photoelectric conversion layer) is formed, and a metal electrode 4 is formed on the organic film 3 as a cathode. The organic film 3 is composed of, for example, a laminate of an organic hole transport layer and an organic photoelectric conversion layer, or is a laminate film in which an electron transport layer is further provided between the organic photoelectric conversion layer and the metal electrode 4. As the metal electrode 4, an MgAg layer, a LiF layer, and an Al layer laminated are used. The short circuit prevention layer 8, silicon oxide SiO _2, aluminum oxide _Al 2 _{O 3,} silicon carbide SiC, silicon nitride _Si 3 _{N 4} other can be used, such as poly-para-xylene.

Specifically, an organic thin film solar cell element was formed on a substrate by the following steps to produce an organic thin film solar cell element housing sealing panel. The production of the organic thin-film solar cell casing encapsulated panel was performed in a clean environment with a cleanliness degree of about 1000 (1000 pieces / ft ³ ). During the manufacturing process of the organic thin-film solar cell element casing sealing panel, all element elements were transported in a high vacuum or nitrogen atmosphere without being exposed to the atmosphere.

  Moreover, in the present Example, the bulk heterojunction type organic thin film solar cell element was used as the organic thin film solar cell element. A bulk heterojunction type organic thin film solar cell element is composed of an anode, an organic hole transport layer, an organic photoelectric conversion layer, and a cathode on a substrate.

  PEDOT: PSS is used as the material for forming the organic hole transport layer, and polythiophene derivatives and fullerene derivatives are used as the material for forming the organic photoelectric conversion layer, and such materials having excellent charge transport properties are combined. Thereby, it can be set as an organic thin-film solar cell element with high energy conversion efficiency.

The reagents used are shown below.
(1) Poly (3-hexylthiophene-2,5-diyl) (Aldrich, Mw-87000) (hereinafter P3HT)
(2) [6,6] -phenyl C61 butyric acid methyl ester (Frontier Carbon Co., E-100) (PCBM)
(3) Poly (styrenesulfonate) / Poly (2,3-dihydrothieno [3,4-b] 1,4-dioxin), 1.3wt.%, Dispersion in water (Aldrich) (PEDOT: PSS)

1) Step 1
As the organic thin film solar cell element substrate 1 for forming the organic thin film solar cell element, a glass substrate on which ITO to be the anode 2 was already patterned was used. The sheet resistance of the anode 2 is preferably 20Ω / □ or less, more preferably 10Ω / □ or less, and particularly preferably 5Ω / □ or less. This is because when the sheet resistance is larger than the above range, the generated photocharge may not be sufficiently transmitted to the external circuit. In this example, an ITO thin film of ITO Nesa Glass IN-100 10Ω / cm ² (1t × 100 × 100 mm) manufactured by Furuuchi Chemical Co., Ltd. was patterned, and a substrate cut into a 50 mm square was used.

  The anode 2 may be a single layer, or may be laminated using materials having different work functions. As the film thickness of the anode 2, the film thickness is in the case of a single layer, the total film thickness is in the range of 0.1 to 500 nm, and the thickness is in the range of 1 nm to 300 nm. Preferably there is. When the film thickness is smaller than the above range, the sheet resistance of the anode 2 becomes too large, and the generated photocharge may not be sufficiently transmitted to the external circuit. On the other hand, when the film thickness is larger than the above range, This is because the total light transmittance is lowered and the energy conversion efficiency may be lowered. This time, it was 200 nm.

  The organic thin film solar cell element substrate 1 was subjected to ultrasonic cleaning using an organic alkali cleaning agent “Semico Clean 56 (manufactured by Furuuchi Chemical Co., Ltd.)”, ultrapure water, acetone and isopropyl alcohol in this order, and then an organic thin film solar cell. The element substrate 1 was blown with nitrogen and then dried by vacuum storage.

2) Step 2
Thereafter, in order to remove organic contaminants on the surface of the ITO transparent electrode 2, UV ozone cleaning treatment was performed, and the substrate was quickly set in the preliminary exhaust chamber. Next, the shadow mask for auxiliary electrodes was installed in the vacuum evaporation apparatus, and the substrate 1 was set. The inside of the vacuum chamber was evacuated to a pressure of 4 × 10 ⁻⁴ Pa or less (in vacuum) using a rotary pump and a turbo molecular pump. The alumina crucible was resistance-heated, and aluminum was deposited to a thickness of 100 nm as an auxiliary electrode. The film formation rate was 10 to 15 nm / min, and film formation was performed at a pressure (in vacuum) of 4 × 10 ⁻⁴ Pa or less. Further, the substrate 1 on which the auxiliary electrode was fabricated was released to atmospheric pressure and taken out from the vacuum chamber into a nitrogen atmosphere.

3) Step 3
Next, the organic thin film solar cell element substrate 1 was transported into a glove box in a nitrogen atmosphere, and a masking protective tape for an organic film was attached on the organic thin film solar cell element substrate 1 here. This is a protective tape for preventing the organic film from being formed in the other part where the part where the organic film is to be formed is opened. As the protective tape, a low-adhesive type protective tape in which no adhesive remains on the substrate 1 was used. For example, IP-300 manufactured by Nitto Denko Corporation is suitable as a masking tape because it has low adhesion, high solvent resistance, 100 ° C. heat resistance, and a thin film thickness of 30 μm. The substrate 1 masked using IP-300 was set on a spin coater.
(Formation of organic hole transport layer)
An organic hole transport layer forming coating solution PEDOT: PSS aqueous dispersion (Aldrich) is applied on the substrate 1 on which the ITO pattern is formed by spin coating, and dried at 100 ° C. for 10 minutes to form an organic material. A hole transport layer (film thickness: about 100 nm) was formed.
(Formation of organic photoelectric conversion layer)
A polythiophene derivative (P3HT, Aldrich) 1.3 wt% and a fullerene derivative (PCBM) 0.1 wt% chlorobenzene (dehydrated) solution were prepared to prepare an organic photoelectric conversion layer coating solution. This coating solution was applied onto the organic hole transport layer by a spin coating method and dried at room temperature for about 10 minutes to form an organic photoelectric conversion layer (film thickness: about 100 nm). The absorption maximum wavelength of the organic photoelectric conversion layer was 540 nm derived from P3HT, and a peak derived from PCBM was also observed at 340 nm.

  Thereafter, the masking tape was peeled off from the surface of the substrate 1, and the metal electrode 4 was set in a preliminary exhaust chamber for vacuum deposition.

4) Step 4
A cathode shadow mask was installed in a vacuum deposition apparatus, and the substrate 1 was set. The inside of the vacuum chamber was evacuated to a pressure of 4 × 10 ⁻⁴ Pa or less (in vacuum) using a rotary pump and a turbo molecular pump. The alumina crucible was resistance-heated, and an aluminum film having a thickness of 100 nm was formed as the cathode 4. The film formation rate was 10 to 15 nm / min, and film formation was performed at a pressure (in vacuum) of 4 × 10 ⁻⁴ Pa or less. Moreover, the area of the photoelectric conversion part of the organic thin-film solar cell element which consists of the laminated structure of the said anode 2, the organic film 3 (organic hole transport layer + organic photoelectric converting layer), and the cathode 4 is 4 mm x 25 mm of the photoelectric converting part. It was set as the board | substrate specification in which four cells form. The substrate 1 after the vacuum deposition was moved from the chamber opened to atmospheric pressure into a glove box in a nitrogen atmosphere without being exposed to the air atmosphere. Furthermore, in a nitrogen atmosphere with a dew point of −80 ° C., the substrate 1 was subjected to a heat treatment at 150 ° C. for 60 seconds on a hot plate to obtain an organic thin film solar cell element. The structure of the produced solar cell element is shown in FIG.

Example 1
(1) Production of inorganic oxide moisture scavenger-containing hot melt type member Barium oxide (particle size of 50 μm or less) as inorganic oxide moisture scavenger and microcrystalline wax (product name “Hi-Mic-1070” Nippon Seiki as wax Co., Ltd., melting point 79 ° C., carbon number of about 30-60, molecular weight of about 500-800) were used. These were mixed at 30% by weight of microcrystalline wax with respect to 70% by weight of barium oxide to obtain a hot melt type member.
(2) Application to a sealing housing (flat glass plate having no recesses) Sealing that has been pre-cleaned and UV ozone cleaned in a glove box that has been replaced with nitrogen gas to a dew point of -70 ° C. The hot melt type member of this example was applied to a housing (glass plate, 42 mm × 42 mm) with a thickness of 50 μm (after drying) (width 36 mm × 36 mm (after drying)) using a dispenser and dried. Any coating method may be used as long as it can be applied to the sealing casing by a single wafer method. Furthermore, a UV curable sealant (UV RESIN XNR 5570-B1 manufactured by Nagase ChemteX Corporation) was applied to the outer peripheral portion of the sealing casing.
(3) Bonding of the organic thin film solar cell element laminated substrate and the sealing housing The organic thin film solar cell element substrate is moved to a glove box substituted with nitrogen gas to a dew point of −70 ° C. without being exposed to the atmosphere. Then, it is brought into close contact with the sealing housing under atmospheric pressure, and irradiated with UV light from a UV lamp of 150 W from the organic thin film solar cell element substrate side, and UV curable epoxy sealant (UV RESIN XNR 5570-Bl Nagase ChemteX After curing, the organic thin-film solar cell element casing sealing panel was obtained by performing heat treatment in a 100 ° C. oven for 1 hour.

  An organic thin-film solar cell element casing sealing panel was obtained by curing the UV curable sealant and sealing.

  A hot melt type member is disposed between the organic thin film solar cell element substrate and the sealing casing without any space, and is directly in close contact with the organic thin film solar cell element.

Example 2
(1) Production of a transparent water scavenger-containing hot melt type member Oledry (trademark) (organometallic compound) manufactured by Futaba Electronics Co., Ltd. as a transparent water scavenger, and microcrystalline manufactured by Nippon Seiki Co., Ltd. as a wax Wax (product name “Hi-Mic-1070”, melting point 79 ° C., carbon number of about 30 to 60, molecular weight of about 500 to 800) was used. These were mixed at a ratio of 13% by weight of heptane and 2% by weight of microcrystalline wax to 85% by weight of ole dry to form a hot melt type member.
(2) Application to a sealing housing (flat glass plate having no recess) Made of glass that has been pre-cleaned and UV ozone cleaned in a glove box that has been replaced with nitrogen gas to a dew point of -70 ° C. A hot melt type member was applied to a sealing casing (42 mm × 42 mm) with a slot die having a thickness of 30 μm (after drying) (width 36 mm × 36 mm (after drying)). As a coating method, it suffices if the pattern coating can be performed on the sealing housing by the single wafer method. Other examples include gravure coating and screen printing. Then, it dried with the hotplate and apply | coated UV hardening type sealing agent (UV RESIN XNR 5570-Bl Nagase ChemteX Co., Ltd. product) to the outer periphery of the hot-melt-type member on the housing | casing for sealing.
(3) Bonding of a substrate on which organic thin-film solar cell elements are laminated and a casing for sealing (a flat glass plate not having a recess) with nitrogen gas without exposing the organic thin-film solar cell element substrate to the atmosphere It moved into the glove box substituted to dew point -70 degreeC, and vacuum bonding was performed with the said housing | casing for sealing previously heated to 60 degreeC. Then, after irradiating ultraviolet rays from the organic thin film solar cell element substrate side with a 150 W UV lamp to cure the UV curable epoxy sealant (UV RESIN XNR 5570-B1 manufactured by Nagase ChemteX Corporation), a 100 ° C. oven The organic thin-film solar cell element housing sealing panel was obtained by sealing by heat-treating for 1 hour.

  A hot-melt type member is filled and disposed between the organic thin film solar cell element substrate and the sealing casing without any space, and is in direct contact with the organic thin film solar cell element.

Example 3
(1) Production of transparent water scavenger-containing hot melt type member The same procedure as in Example 2 was performed.
(2) Transfer to a sealing case (flat glass plate not having a recess) (using a release film)
In a glove box substituted with a dew point of −70 ° C. with nitrogen gas, the hot melt type member of this example is 10 μm (after drying) on a release film (PET100FD Lintec Corporation) (width 36 mm × 36 mm (after drying) )) And coated with a slot die. As a coating method, it is sufficient that the pattern coating can be continuously performed on the release film. Examples of other coating methods include gravure coating and screen printing. Then, it was set as the release film (transfer film) with a hot-melt type member by drying with a hotplate. Further, a cover film was bonded to the hot melt type member on the release film by tangential bonding. As the cover film, a polyethylene film having a slight adhesiveness (manufactured by Sekisui Chemical Co., Ltd.) was used (the adhesive surface of the cover film and the hot melt type member surface were bonded together).

  The transfer film on which the cover film was bonded was wound into a roll and hermetically packaged with a bag of aluminum foil film having a high gas barrier property that was purged with nitrogen.

  Temporary storage was performed in an atmospheric warehouse.

  The transfer film bonded with the cover film was again placed in a glove box purged with nitrogen under the above conditions, and the following transfer operation was performed.

A part of the roll-shaped transfer film was taken out, the cover film was peeled off, and a release film with a hot melt type member was obtained. While the release film is further heated to 60 ° C., the hot-melt type member on the release film is transferred by tangential bonding to a glass sealing case that has been cleaned in advance and subjected to UV ozone cleaning. After cooling, the release film was peeled off. Further, a UV curable sealant (UV RESIN XNR 5570-B1 manufactured by Nagase ChemteX Corporation) was applied to the outer periphery of the hot melt type member of the casing for sealing.
(3) Bonding of a substrate on which organic thin-film solar cell elements are laminated and a casing for sealing (a flat glass plate not having a recess) with nitrogen gas without exposing the organic thin-film solar cell element substrate to the atmosphere Move into the glove box replaced to a dew point of -70 ° C and vacuum-bond with the sealing housing (flat glass plate with no recess, 42mm x 42mm) that has been heated to 60 ° C in advance. went. Then, after irradiating ultraviolet rays with a 150 W UV lamp from the organic thin-film solar cell element substrate side to cure the UV curable epoxy sealant (UV RESIN XNR 5570-Bl manufactured by Nagase ChemteX Corp.), oven at 100 ° C. The organic thin-film solar cell element housing sealing panel was obtained by sealing by heat-treating for 1 hour.

  A hot melt type member is disposed between the organic thin film solar cell element substrate and the sealing casing without any space, and is directly in close contact with the organic thin film solar cell element.

Example 4
(1) Production of transparent water scavenger-containing hot melt type member The same procedure as in Example 2 was performed.
(2) Application to sealing housing (flat glass plate having no recess) The same procedure as in Example 2 was performed.
(3) Bonding of element substrate and sealing casing (flat glass plate having no recess) The organic thin film solar cell element substrate is set in a thermal CVD apparatus without exposing to the atmosphere, and polyparaxylene The system insulating layer was formed to cover the cathode 4 as a short countermeasure layer (FIG. 2). Then, it moved in the glove box substituted with nitrogen gas to dew point -70 degreeC, and vacuum-bonded with the said housing | casing case heated to 60 degreeC beforehand.
Then, after irradiating ultraviolet rays from the element substrate side with a 150 W UV lamp to cure the UV curable epoxy sealant (UV RESIN XNR 5570-Bl Nagase ChemteX Corp.), it is heated in an oven at 100 ° C. for 1 hour. The organic thin-film solar cell element enclosure sealing panel was obtained by sealing by heat-processing.

  A hot melt type member is disposed between the organic thin film solar cell element substrate and the sealing casing without any space, and is in close contact with the organic thin film solar cell element covered with the polyparaxylene-based insulating layer.

Example 5
(1) Preparation of transparent water scavenger-containing hot melt type member (solvent-free type)
A commercially available transparent water scavenger “Oredry (trademark)” (manufactured by Futaba Denshi Kogyo Co., Ltd.) is used as the water scavenger, and microcrystalline wax (product name “Hi-Mic-” manufactured by Nippon Seiki Co., Ltd.) is used as the wax. 1070 ", melting point 79 ° C, carbon number of about 30 to 60, molecular weight of about 500 to 800). After mixing at a ratio of 3% by weight of microcrystalline wax to 97% by weight of the transparent moisture getter agent, the solvent of the obtained mixture was almost completely removed to obtain a hot melt type member (no solvent).
(2) Application to a sealing housing (flat glass plate having no recesses) Glass made by pre-cleaning and UV ozone cleaning in a glove box substituted with dew point -70 ° C with nitrogen gas A hot melt type member (solvent-free) was applied to a sealing casing (42 mm × 42 mm) with a thickness of 30 μm (width 36 mm × 36 mm) with a slot die while heating to 80 ° C. As a coating method, it suffices that the coating can be performed on a sealing casing by a single wafer method. Other examples include gravure coating and screen printing. Then, it dried for 10 minutes at 150 degreeC using the hotplate. The weight loss after drying the hot-melt member after drying under reduced pressure at 150 ° C. for 4 hours under vacuum was 0.05% or less. Further, a UV curable sealant was applied to the outer periphery of the hot melt type member on the sealing casing.
(3) Bonding of element substrate and sealing housing (flat glass plate having no recess) The organic thin film solar cell element substrate was replaced with nitrogen gas to a dew point of −70 ° C. without being exposed to the atmosphere. It moved to the glove box and vacuum-bonded with the said housing | casing for sealing previously heated to 60 degreeC. Then, after irradiating ultraviolet rays with a 150 W UV lamp from the organic thin-film solar cell element substrate side to cure the UV curable epoxy sealant (UV RESIN XNR 5570-Bl manufactured by Nagase ChemteX Corp.), oven at 100 ° C. The organic thin-film solar cell element housing sealing panel was obtained by sealing by heat-treating for 1 hour.

  A hot melt type member is disposed between the organic thin film solar cell element substrate and the sealing casing without any space, and is directly in close contact with the organic thin film solar cell element.

Example 6
(1) Production of transparent water scavenger-containing hot melt type member The same procedure as in Example 5 was performed.
(2) Transfer to a sealing case (flat glass plate not having a recess) (using a release film)
In a glove box substituted with a dew point of −70 ° C. with nitrogen gas, a hot melt type member was coated on a release film with a slot die at a thickness of 30 μm (width 25 mm × 80 mm) while heating to 80 ° C. As a coating method, it is only necessary that pattern coating can be continuously performed on the release film. Other coating methods include gravure coating and screen printing. Thereafter, the film was dried at 150 ° C. for 10 minutes using a hot plate to obtain a release film with a hot melt type member (transfer film). Further, a film (25 mm × 80 mm) made of a hot melt type member is tangentially bonded to a glass sealing case (90 mm × 90 mm) which has been pre-cleaned while being preheated at 60 ° C. and subjected to UV ozone cleaning. Three sheets were arranged and transferred (the distance between the films was about 2 mm), and the release film was peeled off. Further, a UV curable sealant was applied to the outer periphery of three hot-melt members arranged on the sealing casing.
(3) Bonding of element substrate and sealing housing (flat glass plate having no recess) The organic thin film solar cell element substrate (the substrate size is scaled up to 100 mm × 100 mm) is exposed to the atmosphere. Without setting, it was set in a thermal CVD apparatus, and a polyparaxylene-based insulating thin film layer was formed to cover the cathode 4 as a short-circuit prevention layer (FIG. 2). Then, it moved in the glove box substituted by nitrogen gas to the dew point -70 degreeC, and vacuum-bonded with the said housing | casing for sealing previously heated to 60 degreeC. Then, after irradiating ultraviolet rays from the element substrate side with a 150 W UV lamp to cure the UV curable epoxy sealant (UV RESIN XNR 5570-Bl Nagase ChemteX Corp.), it is heated in an oven at 100 ° C. for 1 hour. The organic thin-film solar cell element enclosure sealing panel was obtained by sealing by heat-processing. The three hot-melt type members arranged side by side are fused and adhered to each other, and the hot-melt type member is filled and disposed between the organic thin-film solar cell element substrate and the sealing casing without any space. Directly in close contact with the filling.

Comparative Example 1
(1) Production of transparent moisture scavenger-containing resin member As a transparent moisture scavenger, Futaba Electronics Co., Ltd. Auredry (trademark) was used, and acrylic modified urethane was used as the base resin. These were mixed at a ratio of 25% by weight of acrylic-modified urethane and 25% by weight of MEK with respect to 50% by weight of ole dry to obtain a resin member.
(2) Application to sealing housing (flat glass plate having no recess) The same procedure as in Example 2 was performed.
(3) Bonding of element substrate and sealing housing (flat glass plate having no recesses) Dew point with nitrogen gas without exposing the organic thin film solar cell element substrate (50 mm × 50 mm) to the atmosphere It moved in the glove box substituted to 70 degreeC, and vacuum bonding was performed with the said housing | casing for sealing (42 mm x 42 mm).

  Then, after irradiating ultraviolet rays from the element substrate side with a 150 W UV lamp to cure the UV curable epoxy sealant (UV RESIN XNR 5570-Bl Nagase ChemteX Co., Ltd.), 1 hour in a 100 ° C. oven. The organic thin-film solar cell element casing sealing panel was obtained by sealing by performing the heat treatment.

Comparative Example 2
(1) Production of solar cell without sealing The panel was made without sealing the produced solar cell element.

Comparative Example 3
(1) Production of solar cell using moisture scavenger sheet using cavity glass (sealing cap: 42 mm × 42 mm) A moisture getter sheet manufactured by Dynic Co., Ltd. is attached to the cavity glass as a moisture scavenger. A casing for sealing was obtained.
(2) A moisture getter agent was affixed to a recessed portion of a sealing case using cavity glass (a sealing cap having a concave shape formed by carrying out 0.4 mm counterbore on a glass plate). A UV curable sealant was applied to the outer peripheral part (the bank-shaped part of the frame) of the cavity glass.
(3) Bonding of element substrate and sealing housing Move the organic thin film solar cell element substrate (50 mm × 50 mm) into a glove box substituted with nitrogen gas to a dew point of −70 ° C. without exposing it to the atmosphere. The sealing casing was bonded in an atmospheric pressure. Then, after irradiating ultraviolet rays from the element substrate side with a 150 W UV lamp to cure the UV curable epoxy sealant (UV RESIN XNR 5570-Bl Nagase ChemteX Co., Ltd.), 1 hour in a 100 ° C. oven. The organic thin-film solar cell element enclosure sealing panel was obtained by sealing by heat-processing.

Test example 1
The solar cell characteristics before and after the accelerated standing test of the organic thin-film solar cell element housing sealing panel produced in each example and comparative example were examined.
(1) Evaluation of solar cell characteristics (photoelectric conversion characteristics) 1) Current-voltage curve The performance was evaluated from the current-voltage characteristics of the fabricated cells.

The solar cell was connected in series to an electrochemical measuring instrument (Hokuto Dennko Co. Ltd. HZ-5000), and the dark current was measured while sweeping at a voltage of -1.0 to +1.0 V at 5000 mVmin- ¹ . For photocurrent measurement, a solar simulator (KansaiKagakukikai, XES-502S) was used as a light source. 5 Measurement was performed by irradiating 100 mWcm ⁻² of simulated sunlight from the ITO electrode side. The light intensity was calibrated using an all-weather solarimeter MS-601 (Eihiro Seiki Co., Ltd.). From the photocurrent voltage curve, the short circuit photocurrent: Jsc, the open photovoltage = Voc, the fill factor: FF, and the photoelectric conversion efficiency: η were determined.
2) Calculation of fill factor (FF) FF = (Jmax × Vmax) / (Jsc × Voc)
Jmax: Photocurrent when the maximum electric output is given (mA · cm ⁻² )
Vmax: Photovoltage (V) when giving the maximum electrical output
Jsc: short circuit photocurrent (mA · cm ⁻² )
Voc: Open photovoltage (V)
In the current-voltage curve during light irradiation, the places where the voltage and current are zero are Jsc and Voc, respectively. In addition, when a rectangle having a diagonal line connecting a point on the curve and the origin is drawn, the lengths of two sides of the rectangle having the largest area are Jmax and Vmax (see FIG. 4).
3) Calculation of photoelectric conversion efficiency (η) Photoelectric conversion efficiency: η is defined by the ratio of the maximum electrical output to the incident light intensity (FIG. 4).
η = P / E = (Jmax × Vmax) / E = (Jsc × Voc) × FF / E
P: Maximum electrical output of organic thin film battery (W · cm ⁻² )
E: Energy of incident light (W · cm ⁻² )
(2) Next, each organic thin film solar cell element casing sealing panel (Examples 1 to 6 and Comparative Examples 1 to 3) is placed in a high humidity environment of 60 ° C. × 90% Rh, and an accelerated standing test is performed. went. Table 1 shows the results of the accelerated standing test.

  In a high-temperature and high-humidity environment of 60 ° C. × 90% Rh, the power generation state after 100 hours of the accelerated standing test of Examples 1 to 6 was about 10% lower than that before the accelerated standing test. The initial photoelectric conversion efficiency η of the device of Example 3 was 2.34%, and the photoelectric conversion efficiency η after 100 hours from the accelerated standing test was 2.18%. It was confirmed that the hot melt type member was functioning sufficiently. On the other hand, in Comparative Examples 1 to 3, solar cell characteristics were not recognized after 100 hours due to the influence of moisture and oxygen in the atmosphere such as outgas. In the examples, it was confirmed that no damage due to cracking of the transparent moisture scavenger occurred at all. In addition, from the results of Example 6, it is possible to seal, fill, and seal larger organic thin-film solar cell elements by arranging a plurality of hot-melt members, regardless of the size of the hot-melt members. I found out.

  From the above results, according to the hot-melt type member of the present invention, a hot-melt type member having an arbitrary thickness and pattern can be formed on the sealing housing or the release film. A large-area organic thin-film solar cell element that can maintain stable solar cell characteristics (photoelectric conversion characteristics) without the influence of oxygen and oxygen is configured as a thin organic thin-film solar cell element casing sealing panel that can be mass-produced with high reliability It was confirmed that it was possible. Further, by forming only a hot melt type member on the release film as in Example 3 (using a transfer film), the organic thin film solar cell casing sealing panel can be continuously produced, and productivity is improved. Improvement can be expected. In addition, the hot melt type member can be easily transported to the user, the size can be changed relatively easily, and a flexible response including use by the user can be realized.

*) Accelerated standing test Photoelectric conversion characteristics after 60 ° C x 90% Rh x 100 hours

It is the schematic which shows the cross-section of the conventional organic thin film solar cell element. It is the schematic which shows the cross-section of an example of the organic thin-film solar cell element of this invention. It is the schematic which shows the structure of the solar cell element produced in the Example. It is the figure which put together the photoelectric conversion characteristic after the accelerated leaving test of the test example 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic thin-film solar cell element substrate 2 Anode or ITO transparent electrode 3 Organic layer or organic film 4 Cathode or metal electrode 5 Sealing cap 6 UV curable sealant 7 Moisture scavenger (moisture getter sheet)
8 Short prevention layer 9 Hot-melt type member 10 Housing for sealing

Claims (14)

  A hot-melt type member for organic thin-film solar cells comprising a moisture scavenger and a wax.   The hot-melt member according to claim 1, wherein the moisture scavenger is 1) an organometallic compound and / or 2) a powdered inorganic oxide having an average particle size of 90 µm or less.   The hot melt type member according to claim 1 or 2, wherein a moisture scavenger is contained in the hot melt type member in an amount of 50 to 99% by weight.   The hot melt type member according to any one of claims 1 to 3, wherein wax is contained in the hot melt type member in an amount of 1 to 50% by weight.   The hot-melt member according to any one of claims 1 to 4, wherein the weight loss after drying under reduced pressure at 150 ° C for 4 hours under vacuum is 0.1% or less.   The hot melt type member according to claim 1, wherein the hot melt type member has a thickness of 100 μm or less.   The hot melt type member according to any one of claims 1 to 6, which is used inside the casing of the organic thin-film solar cell element sealed with the casing.   The transfer film which laminated | stacked the hot-melt-type member in any one of Claims 1-7 on the releasable base material.   1) a substrate, 2) an organic thin film solar cell element formed on the substrate, and 3) an organic thin film solar cell case sealing panel including a casing for sealing the organic thin film solar cell element, The organic thin-film solar cell element sealing panel by which the hot-melt type member in any one of Claims 1-7 is arrange | positioned between an organic thin-film solar cell element and the said housing | casing.   The organic thin-film solar cell element casing sealing panel according to claim 9, wherein substantially all of the space between the organic thin-film solar cell element and the casing is occupied by the hot-melt type member.   It is obtained by arranging a plurality of the hot-melt type members on the organic thin-film solar cell element or the casing, and bonding the organic thin-film solar cell element and the casing through the hot-melt type member. The organic thin-film solar cell element housing sealing panel according to claim 10.   The sealing member which laminated | stacked the hot-melt type member in any one of Claims 1-7 on the housing | casing.   1) a substrate, 2) an organic thin film solar cell element formed on the substrate, and 3) an organic thin film solar cell housing sealing panel including a housing for sealing the organic thin film solar cell element. A plurality of the hot-melt type members according to any one of claims 1 to 7 are arranged side by side on the organic thin film solar cell element or the casing, and the organic thin film solar cell element and the casing are arranged in the hot The manufacturing method which has the process of bonding together via a melt-type member.   The organic thin film solar cell element and the casing are bonded together so that substantially all of the space between the organic thin film solar cell element and the casing is occupied by the hot melt type member. The manufacturing method as described.

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