JP2017022169A - Organic thin film solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic thin film solar cell module achieving both handleability and workability.SOLUTION: An organic thin film solar cell module sequentially includes a first gas barrier layer, a first sealing layer, an organic thin film solar cell element, a second sealing layer, and a second gas barrier layer, and satisfies the following conditions 1-3. Condition 1: the ratio of the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer with respect to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer is 0.36 or more. Second condition: the ratio of the sum of the thicknesses of the first sealing layer and the second sealing layer with respect to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer is 0.1 or more. Condition 3: the ratio of the sum of the thicknesses of the first gas barrier layer, the first sealing layer, the second sealing layer, and the second gas barrier layer with respect to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer is 0.8 or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an organic thin film solar cell module.

  In recent years, transparent thin-film solar cell modules using dye-sensitized solar cells, organic thin-film solar cells, and the like have been developed. Moreover, as a product to which the transparent thin film solar cell module is applied, a thin film solar cell module to be attached to a window glass of a building has been proposed (Patent Document 1).

JP 2012-186310 A

  The organic thin-film solar cell module is important in handling and workability of the organic thin-film solar cell module in application to a construction object such as a window glass or a wall surface.

  In general, when affixing a film to an object to be constructed, an aqueous solution of a surfactant diluted 100 to 200 times is used to reduce the adhesive strength of the adhesive, temporarily fix it on the object to be constructed, and use a spatula called a squeegee. By pressurizing and extruding water, the adhesive strength of the adhesive material is restored and the construction is performed in close contact with the construction object. The organic thin film solar cell module is similarly constructed.

  When the present inventors manufactured an organic thin film solar cell module having the same layer thickness as that of the known document 1, the organic thin film solar cell element was broken and damaged during the construction work. In addition, due to the difference in thickness between the area including the organic thin-film solar cell and the area not including the organic thin-film solar cell, the squeegee cannot be squeezed when draining at the time of construction. It was found that there was a problem that water bubbles remained on the surface.

  Then, the organic thin film solar cell module which balances the handleability of a film and workability is provided.

In order to solve the above-mentioned problems, the present inventors have conducted intensive studies focusing on the thickness of the organic thin film solar cell module, the gas barrier layer, and the sealing layer,
(I) When the gas barrier layer having a relatively high Young's modulus is thin in the organic thin film solar cell module, the organic thin film solar cell module becomes soft, and the sealed solar cell element is easily broken and the element is easily damaged (ii) When the sealing layer is made thin, bumps due to current collectors for extracting electricity from the organic thin-film solar cell element and steps due to the difference in thickness between the area where the organic thin-film solar cell element is stacked and the area where it is not formed occur. (Iii) When the gas barrier layer and the sealing layer are thickened, water bubbles are likely to remain between the organic thin-film solar cell module and the work piece during squeegeeing. And the present invention was completed.

Furthermore, (iv) if the adhesive layer laminated on the organic thin film solar cell module is too thick relative to the thickness of the organic thin film solar cell module, it is difficult to perform the squeegee operation at the time of construction. As a result, it was found that bubbles and water residue were generated.

That is, the gist of the present invention is as follows.
[1] An organic thin film solar cell module that has a first gas barrier layer, a first sealing layer, an organic thin film solar cell element, a second sealing layer, and a second gas barrier layer in order, and satisfies the following conditions 1 to 3.
Condition 1: The ratio of the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer is 0.36 or more. Condition 2: the first gas barrier The ratio of the sum of the thicknesses of the first sealing layer and the second sealing layer to the sum of the thicknesses of the layer and the second gas barrier layer is 0.1 or more. Condition 3: The first gas barrier layer to the first gas barrier layer The ratio of the sum of the first gas barrier layer, the first sealing layer, the second sealing layer, and the second gas barrier layer to the sum of the thicknesses of the two gas barrier layers is 0.8 or less. [2] The first gas barrier layer or The organic thin-film solar cell module according to [1], which has an adhesive layer on the outside of the second gas barrier layer.
[3] An organic thin film solar cell module according to [2], which satisfies the following condition 4.
Condition 4: The ratio of the thickness of the adhesive layer to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer and the adhesive layer is from 0.05 to 0.35 [4] The first gas barrier layer The organic thin film solar cell module according to any one of [1] to [3], wherein a sum of thicknesses of the second gas barrier layers is 290 μm or more and 700 μm or less.

  According to the present invention, the solar cell element is not easily damaged during the construction work, the workability of the squeegee and the like is high, the water thin film between the organic thin film solar cell module and the body to be installed is small after the construction, and the organic thin film solar having a high design property A battery module can be provided.

It is a schematic cross section which shows the layer structure of the organic thin-film solar cell module as one Embodiment of this invention. It is a schematic cross section which shows the layer structure of the organic thin-film solar cell module as one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described in detail. The description of the constituent requirements described below is an example (representative example) of an embodiment of the present invention, and the present invention is not limited to these contents unless it exceeds the gist.

1. 1. Organic Thin Film Solar Cell Module 1.1 Configuration An organic thin film solar cell module according to an embodiment of the present invention includes a first gas barrier layer 11, a first sealing layer 21, and an organic thin film solar cell as shown in the schematic diagram of FIG. The element 4, the second sealing layer 22, and the second gas barrier layer 12 are sequentially provided. In addition, in order to take out electricity from the organic thin film solar cell element 4, a pair of collector wires 3 for taking out electricity is installed in the organic thin film solar cell element 4. The current collector 3 is usually installed on the upper electrode or the lower electrode of the organic thin film solar cell element 4. When the organic thin film solar cell module is used for application, it is preferably installed on one surface of the organic thin film solar cell element 4. That is, it is preferable to install a pair of current collectors 3 on either the upper electrode of the organic thin film solar cell element 4 or on either of the current collectors 3 on the lower electrode of the organic thin film solar cell element 4. Any of the current collectors 3 is more preferably installed on the upper electrode of the organic thin film solar cell element 4. That is, it is preferable to have the current collector 3 electrically connected to the organic thin film solar cell element 4 between the first sealing layer 21 and the organic thin film solar cell element 4.

  The first sealing layer 21 and the second sealing layer 22, and the first gas barrier layer 11 and the second gas barrier layer 12 may be the same or different. The current collector 3 is a conductive member for taking out the electric power generated by the organic thin film solar cell element 4 from the organic thin film solar cell module. Although there is no restriction | limiting in the magnitude | size and thickness of the current collection line 3, the one where thickness is thin and small is preferable at the point of the workability and design property mentioned later, and it is as thin as possible according to the magnitude | size of the electric power taken out. Those are preferred.

The organic thin film solar cell module according to the present invention has a first gas barrier layer, a first sealing layer, a thin film solar cell element, a second sealing layer, and a second gas barrier layer in order, and satisfies the following conditions 1 to 3. Fulfill.
Condition 1: The ratio of the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer to the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer is 0.36 or more.

This condition defines the lower limit of the ratio of the thickness of the gas barrier layer to the thickness of the organic thin film solar cell module.
In the present invention, the thickness of the organic thin film solar cell module, that is, the sum of the thicknesses of the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer, The ratio of the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer is 0.36 or more, preferably 0.37 or more, more preferably 0.38 or more, still more preferably 0.39 or more, and particularly preferably 0.40. The upper limit is not particularly limited, but is usually 0.55 or less, preferably 0.50 or less. When the organic thin film solar cell module has a layer other than the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer, the thickness of the organic thin film solar cell module Is preferably the thickness of the solar cell module including the thickness of the layers other than the adhesive layer among the layers other than the above layers.

  By being more than the said lower limit, an organic thin film solar cell module becomes difficult to break, and damage to an organic thin film solar cell element can be prevented, and an organic thin film solar cell module with high workability can be obtained. Moreover, since an organic thin film solar cell module does not become hard too much and it can perform a squeegee appropriately because it is below the said upper limit, it can be set as an organic thin film solar cell module with a good water drain at the time of construction.

  In the present invention, the method for measuring the thickness of the layers constituting the organic thin-film solar cell module is not limited. For example, the vicinity of the center of the organic thin-film solar cell module is cut perpendicularly to the light-receiving surface, and each layer on the cut surface is The thickness can be measured by observing with a microscope.

  Condition 2: The ratio of the sum of the thicknesses of the first sealing layer and the second sealing layer to the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer is 0.1 or more.

This condition defines the lower limit of the ratio of the thickness of the sealing layer to the thickness of the organic thin film solar cell module.
In the present invention, the thickness of the organic thin film solar cell module, that is, the sum of the thicknesses of the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer, The ratio of the sum of the thicknesses of the first sealing layer and the second sealing layer is 0.10 or more, preferably 0.12 or more, more preferably 0.14 or more, still more preferably 0.16 or more, and particularly preferably 0. The upper limit is not particularly limited, but is usually 0.44 or less, preferably 0.40 or less, more preferably 0.35 or less. When the organic thin film solar cell module has a layer other than the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer, the thickness of the organic thin film solar cell module Is preferably the thickness of the solar cell module including the thickness of the layers other than the adhesive layer among the layers other than the above layers.

  By being equal to or more than the above lower limit, there is a step due to a difference in thickness between a convexity by a collector wire for taking out electricity from the organic thin film solar cell element and a region where the organic thin film solar cell element is laminated and a region where the organic thin film solar cell element is not laminated. It becomes hard to generate | occur | produce and can suppress the bubble in an organic thin film solar cell module. And it becomes difficult to produce a level | step difference in the light-receiving surface or non-light-receiving surface of an organic thin-film solar cell module, and it is preferable at the point which can remove a water bubble at the time of construction by a squeegee.

  Condition 3: The ratio of the sum of the first gas barrier layer, the first sealing layer, the second sealing layer, and the second gas barrier layer to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer is 0. 8 or less

This condition defines the upper limit of the thickness of the gas barrier layer and the sealing layer with respect to the thickness of the organic thin film solar cell module.
That is, the first gas barrier layer, the first sealing layer, and the second sealing with respect to the sum of the thicknesses of the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer. The sum ratio of the layer and the second gas barrier layer is 0.80 or less, preferably 0.78 or less, and more preferably 0.75 or less. When the organic thin film solar cell module has a layer other than the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer, the thickness of the organic thin film solar cell module Is preferably the thickness of the solar cell module including the thickness of the layers other than the adhesive layer among the layers other than the above layers.

By being below the above upper limit, it is preferable in that water bubbles between the organic thin-film solar cell module and the workpiece are easily removed during squeegeeing.
The sum of the thicknesses of the first gas barrier layer to the second gas barrier layer, specifically, the thicknesses of the first gas barrier layer, the first sealing layer, the thin-film solar cell element, the second sealing layer, and the second gas barrier layer. The sum of the thickness is usually 290 μm or more, preferably 300 μm or more. Moreover, it is 700 micrometers or less normally, 650 micrometers or less are preferable and 600 micrometers or less are more preferable.

  Although this range prescribes | regulates the thickness of an organic thin film solar cell module, an organic thin film solar cell module is a 1st gas barrier layer, a 1st sealing layer, a thin film solar cell element, a 2nd sealing layer, and 2nd. In the case of having a layer other than the gas barrier layer, the thickness of the organic thin film solar cell module is the thickness of the solar cell module including the thickness of the layer other than the adhesive layer among the layers other than the above layers. preferable.

By being equal to or more than the above lower limit, there is a step due to a difference in thickness between a convexity by a collector wire for taking out electricity from the organic thin film solar cell element and a region where the organic thin film solar cell element is laminated and a region where the organic thin film solar cell element is not laminated. Since it becomes difficult to generate | occur | produce and it becomes difficult to generate | occur | produce a level | step difference in the light-receiving surface or non-light-receiving surface of the organic thin-film solar cell module by these, the water bubble by the water drop defect at the time of construction can be suppressed. By being below the above upper limit, it is possible to perform 12 kg / cm ^2, which is appropriate for general film construction for construction, under the following pressure, and construction by human power can be performed.
If a method other than human power is used, investment in dedicated equipment is unnecessary, and construction can be carried out economically.

Moreover, since the organic thin-film solar cell module of this invention becomes easy to stick and apply to a construction target object, it is preferable to have an adhesion layer on the outer side of a 1st gas barrier layer or a 2nd gas barrier layer.
For example, as shown in FIG. 2, the adhesive layer 5 is provided on the second gas barrier layer 12, and the first gas barrier layer 11, the first sealing layer 21, the thin-film solar cell element 4, the second sealing layer 22, and the second gas barrier. It can be set as the structure which has the layer 21 and the adhesion layer 5 one by one.

When the organic thin film solar cell module has an adhesive layer, an organic thin film solar cell module that satisfies the following condition 4 is more preferable.
Condition 4: The ratio of the thickness of the adhesive layer to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer and the adhesive layer is 3 or more and 20 or less. This condition is relative to the thickness of the organic thin film solar cell module. The range of the thickness of the adhesive layer is specified.

  In the present invention, the adhesion to the thickness of the organic thin film solar cell module, that is, the sum of the thicknesses of the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer. The ratio of layer thickness is 0.05 or more, preferably 0.10 or more, more preferably 0.15 or more, still more preferably 0.20 or more, 0.35 or less, preferably 0.34 or less, and more It is preferably 0.33 or less, more preferably 0.32 or less, particularly preferably 0.31 or less, and most preferably 0.30 or less. When the organic thin film solar cell module has a layer other than the first gas barrier layer, the first sealing layer, the thin film solar cell element, the second sealing layer, and the second gas barrier layer, the thickness of the organic thin film solar cell module Is preferably the thickness of the solar cell module including the thickness of the layers other than the adhesive layer among the layers other than the above layers.

By being below the above upper limit, it is preferable in that the squeegee work can be easily performed at the time of construction and water bubbles are easily removed at the time of squeegee. By being more than the said minimum, it is preferable at the point which is easy to remove a water bubble in the case of a squeegee.
Organic thin-film solar cell modules can use a thin current collector as much as the electrical resistance allows for power extraction. However, since there are steps in the element, there are also steps in the fabricated module. . When the thickness of the adhesive layer with respect to the thickness of the organic thin-film solar cell module is equal to or more than the lower limit, the adhesive layer absorbs the module step and can easily drain water during construction, thereby preventing construction defects such as water bubbles. . If it is below the above upper limit, the drainage pressure at the time of construction can be applied manually, and the drainage at the time of construction is easy to perform, so that construction defects can be prevented.

  The pressure-sensitive adhesive layer can be formed of a conventionally known pressure-sensitive adhesive, but an acrylic pressure-sensitive adhesive is preferable from the viewpoint of weather resistance and transparency. The adhesive layer can be provided by a known method on the outermost layer on the substrate side (light receiving surface) or the photoelectric conversion layer side (non-light receiving surface) of the organic thin film solar cell element used in the organic thin film solar cell module. From the viewpoint of power generation efficiency of the thin-film solar cell element, it is preferable to provide it on the outermost layer on the substrate side (light-receiving surface) of the organic thin-film solar cell element.

  The organic thin film solar cell module preferably has translucency. As for the translucency of the organic thin film solar cell module, the visible light transmittance measured by a method according to JIS R 3106 is usually 3% or more, preferably 5% or more, more preferably 8% or more, still more preferably 10% or more. Particularly preferably, it is 20% or more, usually 80% or less, preferably 60% or less, more preferably 50% or less. It is preferable that it is at least the above lower limit in that the daylighting property can be improved. It is preferable at the point which can improve electric power generation efficiency by being below the said upper limit.

The organic thin film solar cell module having translucency is, for example, an organic thin film solar cell element having translucency by using a transparent electrode as an electrode of the organic thin film solar cell element, and an organic thin film other than the organic thin film solar cell element. This can be realized when the constituent members of the solar cell module have translucency.
Hereafter, the structural member of the thin film solar cell module of this invention is demonstrated.

1.2 Constituent member 1.2.1 Gas barrier layer (first gas barrier layer 11 and second gas barrier layer 12)
The gas barrier layer is a layer that prevents permeation of water and oxygen. By the gas barrier layer, the organic thin film solar cell element can be prevented from being deteriorated by moisture or oxygen, and the performance can be maintained over a long period of time. Since design properties such as light transmittance and transparency can be improved in addition to the long-term durability described above, it is more preferable that the gas barrier layer also serves as a protective layer described later.

Organic thin-film solar cell elements tend to deteriorate due to moisture and oxygen, and in particular, transparent electrodes such as ZnO: Al and organic semiconductor layers tend to deteriorate due to moisture and oxygen. Therefore, by covering the organic thin film solar cell element with the gas barrier layer, the organic thin film solar cell element can be protected from water and oxygen, and the power generation performance can be kept high.
In the following description, the gas barrier layer refers to each of the first gas barrier layer 11 and the second gas barrier layer 12.

  The thickness of the gas barrier layer is usually 50 μm or more, preferably 75 μm or more, and is usually 120 μm or less, preferably 100 μm or less. Increasing the thickness tends to increase gas barrier properties, and decreasing the thickness tends to increase flexibility and improve visible light transmittance.

The degree of moisture-proof capability required for the gas barrier layer is such that the water vapor permeability per unit area (1 m ² ) per day is preferably 1 × 10 ⁻¹ g / m ² / day or less, and 1 × 10 ⁻ It is more preferably ² g / m ² / day or less, further preferably 1 × 10 ⁻³ g / m ² / day or less, and more preferably 1 × 10 ⁻⁴ g / m ² / day or less. Among these, 1 × 10 ⁻⁵ g / m ² / day or less is particularly preferable, and 1 × 10 ⁻⁶ g / m ² / day or less is particularly preferable. As the permeation of water vapor is suppressed, deterioration due to the reaction of the organic thin film solar cell element and the transparent electrode such as ZnO: Al of the element with moisture is suppressed, so that the lifetime is extended by maintaining the power generation efficiency.

The degree of oxygen permeability required for the gas barrier layer is such that the oxygen permeability per unit area (1 m ² ) per day is preferably 1 × 10 ⁻¹ cc / m ² / day / atm or less. More preferably, it is below 10 × ^{2 −2} cc / m ² / day / atm, further preferably below 1 × 10 ⁻³ cc / m ² / day / atm, and further below 1 × 10 ⁻⁴ cc / m ^2. / Day / atm or less is preferable, 1 × 10 ⁻⁵ cc / m ² / day / atm or less is particularly preferable, and 1 × 10 ⁻⁶ cc / m ² / day / atm or less. Is particularly preferred. The deterioration due to oxidation of the organic thin-film solar cell element and the transparent electrode such as ZnO: Al of the element is suppressed as oxygen does not permeate.

  By applying such a gas barrier layer, it becomes easy to implement an organic thin film solar cell module utilizing the excellent properties of the organic solar cell element.

  Further, the gas barrier layer is preferably one that transmits visible light from the viewpoint of not hindering light absorption of the organic thin film solar cell element. For example, the transmittance of visible light (wavelength 360 to 830 nm) is usually 60% or more, preferably 70% or more, more preferably 75% or more, still more preferably 80% or more, and particularly preferably 85% or more. Preferably it is 90% or more, Especially preferably, it is 95% or more, Especially preferably, it is 97% or more. This is to convert more sunlight into electrical energy.

  Furthermore, the gas barrier layer preferably has a low haze from the viewpoint of design properties such as a sense of unity with the construction object and appearance. For example, the haze value when using a D65 light source defined by JIS K 7136 is usually 10 or less, preferably 5 or less, more preferably 2 or less, and even more preferably 1 or less.

  Further, since the organic thin film solar cell module is often heated by receiving light, it is preferable that the gas barrier layer also has heat resistance. From this viewpoint, the melting point of the constituent material of the gas barrier layer is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and usually 350 ° C. or lower, preferably 320 ° C. or lower, more preferably 300 It is below ℃. By increasing the melting point, it is possible to reduce the possibility that the gas barrier layer melts and deteriorates when the organic thin film solar cell module is used.

  The specific configuration of the gas barrier layer is arbitrary as long as the organic thin-film solar cell element can be protected from water. However, since the manufacturing cost increases as the amount of water vapor or oxygen that can permeate the gas barrier layer increases, it is preferable to use an appropriate material in consideration of these points comprehensively.

Among them, a suitable gas barrier layer includes, for example, a laminate obtained by vacuum-depositing SiOx on a base film such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).
Note that the gas barrier layer may be formed of one kind of material or two or more kinds of materials. The gas barrier layer may be formed as a single layer, but may be a laminate of two or more layers. Furthermore, you may use the gas barrier layer of a different material for a light-receiving surface and a back surface.

  As long as the gas barrier layer can cover the organic thin film solar cell element and protect it from moisture and oxygen, the formation position is not limited, but both sides of the organic thin film solar cell element, specifically, the light receiving surface side and the light receiving surface It is preferable to cover the opposite surface. This is because in the thin film solar cell module, the light receiving surface side surface and the surface opposite to the light receiving surface are often formed in a larger area than the other surfaces. In the present embodiment, the gas barrier layer is disposed so as to cover the light receiving surface side of the organic thin film solar cell element and the surface opposite to the light receiving surface.

  There are no particular restrictions on the positional relationship and relative size of the gas barrier layer and the sealing layer, but usually the sealing layer and the gas barrier layer are laminated with the same size and the same shape and with the ends aligned. Alternatively, the gas barrier layer covers the entire surface of the sealing layer, and the gas barrier layer is laminated larger than the sealing layer. In order to prevent deterioration due to moisture or oxygen and maintain the performance of the solar cell element over a long period of time, the distance between the end face of the gas barrier layer and the end face of the solar cell element substrate is 5 mm or more, preferably 10 mm or more. Further, it is preferable that the end face of the gas barrier layer is disposed outside the end face of the solar cell element substrate.

  In addition, the gas barrier layer has a hard coat layer to prevent damage when handling the thin film solar cell module, to prevent damage due to a squeegee when applying water to a construction object, and to improve the smoothness of the gas barrier layer. May be provided.

  As this hard coat layer, conventionally known ones can be used, such as an ultraviolet curable resin; an electron beam curable resin; an alkoxysilane hydrolytic condensation resin; a melamine resin; a (meth) acrylate alcohol-modified polyfunctional compound; Examples include layers made of acrylic resins such as trimethylolpropane (meth) acrylate, tripropylene glycol diacrylate, pentaerythritol triacrylate, 1,6 hexanediol (meth) acrylate, but are not limited thereto. . The hard coat layer preferably has a pencil hardness of 2H or higher, more preferably 3H or higher. Moreover, it is preferable that the film thickness is 1-10 micrometers. If it is less than 1 μm, the effect of scratch resistance may not be sufficient, and if it is 10 μm or more, the gas barrier layer may curl due to curing shrinkage of the hard coat layer.

1.2.2 Sealing layer (first sealing layer 21 and second sealing layer 22)
In the present invention, an organic thin film solar cell module is manufactured by connecting an organic thin film solar cell element and a collector wire, and the organic thin film solar cell element is sealed with a gas barrier layer via a sealing layer. The organic thin-film solar cell element is sealed in order to reinforce the organic thin-film solar cell element and increase impact resistance. In the following description, the sealing layer refers to each of the first sealing layer 11 and the second sealing layer 22.

  The sealing layer used for sealing preferably has high bending strength from the viewpoint of maintaining the strength of the organic thin film solar cell module. The specific strength is related to the strength of the layers other than the sealing material and is difficult to define in general, but the entire organic thin-film solar cell module has good bending workability and causes peeling of the bent portion. It is desirable to have such bending strength.

  Moreover, when a sealing layer is used for the light-receiving surface side of an organic thin-film solar cell element, what transmits visible light from a viewpoint which does not prevent light absorption is preferable. For example, the transmittance of visible light (wavelength 360 to 830 nm) is usually 75% or more, preferably 80% or more, more preferably 85% or more, more preferably 90% or more, particularly preferably in a single sealing layer. Is 95% or more, particularly preferably 97% or more. This is to convert more sunlight into electrical energy.

  Further, the sealing layer preferably has a low haze from the viewpoint of design properties such as a sense of unity with the construction object and appearance. For example, the haze value when using a D65 light source defined by JIS K 7136 is usually 15 or less, preferably 10 or less, more preferably 5 or less, and even more preferably 2 or less in a single sealing layer.

  On the other hand, the sealing layer on the opposite side of the light-receiving surface of the organic thin-film solar cell element does not necessarily need to transmit visible light and may be opaque, but in order to paste it on a transparent construction object such as a window glass, It is preferable to have the same visible light transmittance and haze as the light receiving surface side of the organic thin film solar cell element.

  Furthermore, since the organic thin film solar cell module is often heated by receiving light, it is preferable that the sealing material also has heat resistance. From this viewpoint, the melting point of the constituent material of the sealing layer is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and usually 350 ° C. or lower, preferably 320 ° C. or lower, more preferably It is 300 degrees C or less. By increasing the melting point, it is possible to prevent the sealing layer from melting and deteriorating when the organic thin film solar cell module is used.

  Each thickness of the first sealing layer or the second sealing layer is 30 μm or more, preferably 40 μm or more, more preferably 50 μm or more, and usually 100 μm or less, preferably 80 μm or less, more preferably 60 μm or less. . Increasing the thickness tends to increase the strength of the entire organic thin-film solar cell module, and decreasing the thickness tends to increase flexibility and improve visible light transmittance. For this reason, it is desirable to set it as the said range as a range which has both advantages.

  The ratio T1 / (T1 + T2) of the thickness T1 of the first sealing layer to the sum of the thickness T1 of the first sealing layer and the thickness T2 of the second sealing layer is not particularly specified, but is usually 0.3 to The range is 0.7, preferably 0.4 to 0.6, and more preferably 0.5. When the thickness ratio is in this range, an organic thin-film solar cell module having good handling properties and no water bubbles remaining at the time of water application is obtained. On the other hand, when it exceeds this range, the warpage of the organic thin film solar cell module becomes large, and stable construction cannot be performed, so that water bubbles are likely to remain at the time of water application.

  The material constituting the sealing layer is not particularly limited, and a thermoplastic resin such as a vinyl acetate-ethylene copolymer composition containing a crosslinking agent, a thermosetting resin such as polyurethane or epoxy resin, a polyolefin, polyester, or an acrylic resin. It may be a resin, an elastomeric resin such as butyl rubber or silicone rubber, or the above composite.

  The sealing layer has a temperature capable of sealing of usually 50 ° C. or higher, preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and usually 250 ° C. or lower, preferably 200 ° C. or lower, more preferably 180 ° C. or lower, still more preferably. Is 160 ° C. or lower, particularly preferably 140 ° C. or lower. In the present invention, it is preferable that the sealing layer contains the thermosetting resin in that the organic thin film solar cell module is not easily deformed even when exposed to high temperatures. Furthermore, when the sealing layer contains a thermosetting resin such as an epoxy resin, it is preferable because the sealing layer, which is a thermosetting resin, can be simultaneously cured when the organic thin film solar cell module is sealed.

  The curing temperature of the thermosetting resin contained in the sealing layer (that is, the curing temperature of the sealing material containing the thermosetting resin) is usually 50 ° C. or higher, preferably 100 ° C. or higher, and usually 250 ° C. or lower, preferably Is 200 ° C. or lower, more preferably 180 ° C. or lower, still more preferably 160 ° C. or lower, and particularly preferably 140 ° C. or lower.

Note that the sealing layer may be formed of one kind of material or two or more kinds of materials. The sealing layer may be a single layer or a laminate of two or more layers. Further, the light receiving surface side and the back surface side may be different types of materials.
The sealing layer is usually provided so as to sandwich the organic thin film solar cell element.

Further, the sealing layer may be provided with functions such as ultraviolet blocking, heat blocking, conductivity, antireflection, antiglare, light diffusion, light scattering, wavelength conversion, and gas barrier properties. In particular, the organic thin film solar cell element is weak against water and oxygen and is exposed to strong ultraviolet rays from sunlight, and therefore preferably has a gas barrier property and an ultraviolet blocking function.
As a method for imparting such a function, a layer having a function may be laminated on the sealing layer by coating film formation or the like, or a material that exhibits a function may be dissolved and dispersed in the sealing material. You may make it contain.

Examples of the gas barrier property include those satisfying the following water vapor permeability and oxygen permeability.
As the water vapor transmission rate, the water vapor transmission rate Pd when the sealing material is 100 μm thick is usually 10 ⁻¹ g / m ² / day or less, preferably 10 ⁻² g / m ² / day, in an environment of 40 ° C. and 90% RH. Hereinafter, it is more preferably 10 ⁻³ g / m ² / day or less, still more preferably 10 ⁻⁴ g / m ² / day or less. The water vapor transmission rate is measured in an environment of 40 ° C. and 90% RH by a measurement using an apparatus equipped with a humidity sensor, an infrared sensor, and a gas chromatograph according to JIS K7129, or by a cup method (JIS Z0208).

As the oxygen permeability, for example, generally, the oxygen permeability per day of a unit area (1 m ² ) at a thickness of 100 μm in a 25 ° C. environment is usually 1 cc / m ² / day / atm or less. , 1 is preferably × 10 ^-1 or less ^{cc / m 2 / day / atm} , more preferably not more than ^{1 × 10 -2 cc / m 2} / day / atm, 1 × 10 -3 cc / m ² / day / atm or less is more preferable, 1 × 10 ⁻⁴ cc / m ² / day / atm or less is particularly preferable, and 1 × 10 ⁻⁵ cc / m ² / day / atm or less. It is particularly preferred. There is an advantage that the deterioration due to the oxidation of the element can be suppressed as the oxygen does not permeate. The oxygen permeability can be measured with an apparatus based on a differential pressure method according to JIS K7126A, or an apparatus equipped with an infrared sensor and a gas chromatograph based on an isobaric method according to JIS K7126B.

The sealing layer is usually formed by laminating a sealing material and an organic thin film solar cell element, preferably by laminating a laminate of a gas barrier layer and a sealing layer and an organic thin film solar cell element. Is done. The step of laminating the sealing material on the organic thin film solar cell element may be performed after the step (step 1) of installing the collector wire on the organic thin film solar cell element, or may be performed before step 1.
When it has the process of laminating | stacking a sealing material on an organic thin-film solar cell element after the process 1, a sealing material is laminated | stacked on the organic thin-film solar cell element in which the current collection line was installed, and the current collection line | wire of a sealing material is used. A slit can be formed in the place to take out, and a current collection line can be taken out from this slit. The number of locations where the collector wire is connected to the upper electrode of the organic thin film solar cell element is arbitrary as long as it is one or more. In the case where a plurality of organic thin film solar cell elements are connected in series, a collector wire may be connected to the organic thin film solar cell element so that a desired potential can be taken out.

  When it has the process of laminating | stacking a sealing material on an organic thin film solar cell element before the process 1, a slit is formed in the sealing material after sealing, and the upper electrode of an organic thin film solar cell element is exposed in a slit It will be in the state. And what is necessary is just to connect the upper electrode and collector wire of the position of a slit. Moreover, by providing a slit at a specific position in advance in the sealing material before sealing, the labor of forming the slit after sealing can be saved. Providing slits in advance in this way makes it possible to eliminate the possibility of damage to the organic thin film solar cell element that occurs when the slits are formed after sealing.

The ratio of the sum of the thicknesses of the gas barrier layers to the sum of the thicknesses of the sealing layers is preferably 0.5 or more, more preferably 1 or more, and still more preferably 2 or more. Moreover, 5 or less is preferable, 4.5 or less is more preferable, and 3 or less is still more preferable.
In the organic thin film solar cell module of the present invention, the rigidity of the organic thin film solar cell module is increased by the barrier layer formed of a material having a high Young's modulus among the materials constituting the organic thin film solar cell module. Protects against bending, dents, etc., and reduces element destruction.

By being above the lower limit, the ratio of the gas barrier layer formed of a material having a high Young's modulus to the sealing layer formed of a material having a low Young's modulus is ensured, and the organic thin film is formed by bending or denting of the organic thin film solar cell module. It is preferable at the point which can reduce the fear of a solar cell element destruction. Especially suitable for sticking installation that is often performed by human hands. By being below the above upper limit, a sealing layer formed of a material having a low Young's modulus relative to a gas barrier layer formed of a material having a high Young's modulus. Therefore, it is possible to suppress quality defects such as bubbles, wrinkles, and sink marks during module fabrication.

1.2.3 Organic thin-film solar cell element An organic thin-film solar cell element usually has a structure in which a lower electrode, an organic photoelectric conversion layer, and an upper electrode are sequentially laminated on a substrate.

  The organic thin-film solar cell element used for the organic thin-film solar cell module of the present invention has characteristics that are strong in handling properties during water pasting and bending of the organic thin-film solar cell module. In the present invention, the organic thin film solar cell element preferably means an organic solar cell element having a thickness of 150 μm or less.

  The organic thin film solar cell element is preferable in that the organic photoelectric conversion layer can be produced by coating and has excellent design properties. By using the organic photoelectric conversion layer, the productivity of the organic thin film solar cell element is particularly excellent, and it is particularly preferable because it meets the object of the present invention.

1.2.3.1 Substrate The substrate is a member that supports the organic thin-film solar cell element. The material of the substrate is not particularly limited as long as the present invention can be applied, and known materials such as inorganic materials, organic materials, paper materials, and composite materials can be used. Specifically, inorganic materials such as quartz, glass, sapphire or titania; polyethylene terephthalate, polyethylene naphthalate, polyethersulfone, polyimide, nylon, polystyrene, polyvinyl alcohol, ethylene vinyl alcohol copolymer, fluororesin, vinyl chloride or Polyolefins such as polyethylene; Organic materials such as cellulose, polyvinylidene chloride, aramid, polyphenylene sulfide, polyurethane, polycarbonate, polyarylate, polynorbornene or epoxy resin; Paper materials such as paper or synthetic paper; Metals such as stainless steel, titanium or aluminum In addition, a composite material such as a material whose surface is coated or laminated in order to impart insulating properties may be used. Of these, resin substrates using organic materials can provide transparency to the substrate, so both superstrate and substrate structures can be created, and translucent see-through solar cells can be created. Is preferable in that it is possible.

  Among them, the substrate is preferably a flexible (flexible) substrate. This is because the substrate is flexible, so that the organic thin film solar cell element can be manufactured by a roll-to-roll method, and the degree of freedom in designing and installing the organic thin film solar cell module is improved. “Flexible” means, for example, that the material does not break (plastically deform) even when bent at a curvature radius of 170 mm. Among the above materials, the flexible substrate material is preferably an organic material, a paper material, or a composite material, more preferably an organic material or a composite material, and particularly preferably an organic material.

  The organic material usually has Tm (melting temperature) and Tg (glass transition temperature), but the deterioration of the appearance due to deformation of the substrate is suppressed by sealing the organic thin film solar cell element at less than Tm, preferably less than Tg. be able to.

  When the substrate is a resin substrate, the glass transition temperature (Tg) of the resin substrate is usually 30 ° C. or higher, preferably 50 ° C. or higher, usually 400 ° C. or lower, preferably 300 ° C. or lower, more preferably 200 ° C. or lower, More preferably, it is 160 degrees C or less. When the glass transition temperature (Tg) is in the above range, it is easy to perform molding when producing a resin substrate, and deformation is less likely to occur during the production of solar cells.

  The glass transition temperature in the present specification is a value obtained by differential scanning calorimetry (DSC) defined in JIS K-7121 1987 “Method for measuring plastic transition temperature”.

  Although there is no restriction | limiting in the thickness of a board | substrate, it is 5 micrometers or more normally, Preferably it is 20 micrometers or more, and is 20 mm or less normally, Preferably it is 10 mm or less. It is preferable that the thickness of the substrate is 5 μm or more because the possibility that the strength of the organic thin film solar cell element is insufficient is reduced. It is preferable that the thickness of the substrate is 20 mm or less because the cost is suppressed and the weight does not increase. When the material of the substrate is glass, the thickness is usually 0.01 mm or more, preferably 0.1 mm or more, and is usually 1 cm or less, preferably 0.5 cm or less. It is preferable that the thickness of the substrate is 0.01 mm or more because mechanical strength is increased and cracking is difficult. Moreover, it is preferable that the thickness of the substrate is 0.5 cm or less because the weight does not increase.

  Although there is no restriction | limiting in the length of a board | substrate, Usually, 10 cm or more, Preferably it is 1 m or more, More preferably, it is 10 m or more, More preferably, it is 50 m or more, Most preferably, it is 100 m or more. The upper limit is usually 10 km or less, preferably 5 km or less, more preferably 1 km or less, still more preferably 500 m or less.

  When manufactured by a roll-to-roll method, it is usually 10 m or more, preferably 20 m or more, more preferably 50 m or more, still more preferably 100 m or more, and particularly preferably 200 m or more. Although an upper limit in particular is not restrict | limited, Usually, it is 10 km or less, Preferably it is 5 km or less, More preferably, it is 1 km or less. By setting the length within this range, efficient production by a roll-to-roll system can be performed. In the roll-to-roll method, since it takes time to switch the roll, in order to reduce the time loss due to the switching of the roll, it is preferable that the substrate of one roll is as long as the manufacturing apparatus allows. On the other hand, it should be noted that handling becomes difficult when the roll becomes heavy.

1.2.3.2 Electrodes (lower and upper electrodes)
The organic thin film solar cell element has two or more electrodes so as to sandwich the organic photoelectric conversion layer. In the present invention, the substrate-side electrode is the lower electrode, and the electrode opposite to the substrate is the upper side with respect to the organic photoelectric conversion layer. It is called an electrode. In the present invention, these electrodes have a function of collecting holes and electrons generated by light absorption. Therefore, as these electrodes, an electrode suitable for collecting holes (hereinafter also referred to as an anode) is used on one side, and an electrode suitable for collecting electrons (hereinafter also referred to as a cathode) on the other side. It is preferable to use The lower electrode may be an anode, the upper electrode may be a cathode, the lower electrode may be a cathode, and the upper electrode may be an anode. Any one of the lower electrode and the upper electrode may be translucent, and both may be translucent.

  In the present invention, being translucent means that the transmittance of sunlight rays, that is, the ratio of transmitting light having a wavelength of 360 to 830 nm in sunlight is 40% or more. The solar ray transmittance is preferably 50% or more, more preferably 60% or more, and still more preferably 70% or more.

In addition, it is preferable that the transparent electrode has a solar ray transmittance of usually 70% or more in order to allow light to reach the organic photoelectric conversion layer through the transparent electrode.
These light transmittances are values measured in accordance with JIS 7375: 2008.

The lower electrode and the upper electrode can be formed of a conductive material, for example, a metal such as platinum, gold, silver, aluminum, chromium, nickel, copper, titanium, magnesium, calcium, barium, sodium, or the like Alloys thereof; metal oxides such as nickel oxide, indium oxide, tungsten oxide, tin oxide, and zinc oxide; or indium-tin oxide (ITO), indium-zinc oxide (IZO), indium-tungsten oxide ( Composite oxides such as IWO); conductive polymers such as polyaniline, polypyrrole, polythiophene, and polyacetylene; acids such as hydrochloric acid, sulfuric acid, and sulfonic acid, Lewis acids such as FeCl ₃ , and halogens such as iodine Include dopants such as atoms, sodium, potassium and other metal atoms Ones; metal particles, carbon black, fullerenes, conductive particles such as carbon nanotube and a composite material matrix of dispersed electrically conductive, such as polymeric binder and the like.

  Among these, a material having a deep work function such as Au or ITO is preferable for the electrode for collecting holes. On the other hand, for the electrode for collecting electrons, a material having a shallow work function such as Al is preferable. By optimizing the work function, there is an advantage of favorably collecting holes and electrons generated by light absorption.

  At least the electrode on the light-receiving surface side has optical transparency and is preferably transparent. However, the electrode is not necessarily transparent if it does not significantly adversely affect the power generation performance. If the material of a transparent electrode is mentioned, said metal oxide, composite oxide, a metal thin film, etc. will be mentioned, A metal oxide and composite oxide are preferable. Further, the light transmittance of the upper electrode is preferably 80% or more, excluding loss due to partial reflection at the optical interface, considering the power generation efficiency of the organic thin film solar cell element.

The materials for the lower electrode and the upper electrode may be used alone or in combination of two or more in any combination and ratio.
In the present invention, a metal thin film made of metal or alloy can be preferably exemplified as the upper electrode. Since the metal thin film has high conductivity, it is preferable in that it requires less material than using other materials such as a conductive polymer. Further, it is preferable in that the film can be formed by vacuum film formation, and damage to the base can be suppressed as compared with the coating process.

  In the present invention, when either one of the upper electrode and the lower electrode is translucent, it is preferable that the lower electrode formed on the substrate side has translucency. That is, by using a metal or alloy having a predetermined thickness as the upper electrode, it is easy to install the current collector with respect to the upper electrode, and the resistance between the current collector and the electrode can be easily lowered.

  In addition, this invention can be used conveniently when the electrode which installs a current collection line is formed including the metal or the alloy. When a current collector is installed via a metal paste on a metal or alloy, especially an electrode formed containing a metal, the metal forming the electrode reacts with the components contained in the metal paste to deform the electrode. And problems such as discoloration may occur. According to the present invention, such a problem can be solved and an organic thin-film solar cell excellent in appearance can be provided.

  There is no restriction | limiting in the formation method of a lower electrode and an upper electrode. For example, it can be formed by a dry process such as vacuum deposition or sputtering. It can also be formed by a wet process using conductive ink or the like. As this conductive ink, for example, a conductive polymer, a metal particle dispersion, or the like can be used. Furthermore, two or more electrodes may be laminated, and characteristics (electric characteristics, wetting characteristics, etc.) due to surface treatment may be improved.

The thicknesses of the upper electrode and the lower electrode are not particularly limited, but are usually 5 nm or more, preferably 10 nm or more, more preferably 20 nm or more, and further preferably 50 nm or more. On the other hand, it is usually 400 μm or less, preferably 10 μm or less, more preferably 1 μm or less, and further preferably 500 nm or less. When the thickness of the electrode is equal to or more than the lower limit, sheet resistance is suppressed and sufficient conduction is possible. On the other hand, by being below the above upper limit, flexibility can be maintained. When the electrode is a transparent electrode, it is necessary to select a film thickness that can achieve both light transmittance and sheet resistance.
The sheet resistance of the electrode is not particularly limited, but is usually 1Ω / □ or more, on the other hand, 1000Ω / □ or less, preferably 500Ω / □ or less, more preferably 100Ω / □ or less.

1.2.3.3 Organic photoelectric conversion layer The organic photoelectric conversion layer is formed of an organic semiconductor. Organic semiconductors are classified into p-type and n-type depending on semiconductor characteristics. The p-type and n-type indicate whether it is a hole or an electron that contributes to electrical conduction, and depends on the electronic state, doping state, and trap state of the material. Therefore, there are cases where p-type and n-type cannot always be clearly classified, and there are cases where the same substance exhibits both p-type and n-type characteristics.

Examples of p-type semiconductors include high molecular organic semiconductor compounds and low molecular organic semiconductor compounds.
The polymer organic semiconductor compound is not particularly limited, and is a conjugated polymer semiconductor such as polythiophene, polyfluorene, polyphenylene vinylene, polythienylene vinylene, polyacetylene or polyaniline; a polymer such as oligothiophene substituted with an alkyl group or other substituents Semiconductor; and the like. Moreover, the semiconductor polymer which copolymerized 2 or more types of monomer units is also mentioned. Examples of the conjugated polymer include Handbook of Conducting Polymers, 3rd Ed. (2 volumes), 2007, Materials Science and Engineering, 2001, 32, 1-40, Pure Appl. Chem. Use polymers that can be synthesized by a combination of polymers described in known literature such as 2002, 74, 2031-3044, Handbook of THIOPHENE-BASED MATERIALS (2 volumes), 2009, and derivatives thereof, and combinations of the described monomers. Can do. The polymer organic semiconductor compound used as the p-type semiconductor compound may be a single compound or a mixture of a plurality of compounds.

  The low-molecular organic semiconductor compound is not particularly limited as long as it can function as a p-type semiconductor material. Specifically, condensed aromatic hydrocarbons such as naphthacene, pentacene, or pyrene; α-sexithiophene, etc. Oligothiophenes containing 4 or more thiophene rings; including at least one of thiophene ring, benzene ring, fluorene ring, naphthalene ring, anthracene ring, thiazole ring, thiadiazole ring and benzothiazole ring, and a total of 4 or more linked A phthalocyanine compound and a metal complex thereof, or a porphyrin compound such as tetrabenzoporphyrin and a macrocycle such as a metal complex thereof. Preferably, they are a phthalocyanine compound and its metal complex, or a porphyrin compound and its metal complex. The molecular weight of the low-molecular organic semiconductor compound is not particularly limited both at the upper limit and the lower limit, but is usually 5000 or less, preferably 2000 or less, and is usually 100 or more, preferably 200 or more. In addition, when forming a p-type semiconductor layer by application | coating, a low molecular organic-semiconductor compound precursor can be converted into a low-molecular-weight organic semiconductor compound after application | coating. A method using a low molecular weight organic semiconductor compound precursor is more preferable in that coating film formation is easier. A low molecular organic semiconductor compound precursor is a compound that changes its chemical structure and is converted into a low molecular organic semiconductor compound by applying an external stimulus such as heating or light irradiation. A low molecular organic semiconductor compound precursor is preferable in that it has excellent film-forming properties.

  Examples of p-type semiconductors include porphyrin compounds such as tetrabenzoporphyrin, tetrabenzocopper porphyrin, and tetrabenzozinc porphyrin; phthalocyanine compounds such as phthalocyanine, copper phthalocyanine, and zinc phthalocyanine; naphthalocyanine compounds; tetracene and pentacene polyacenes; And derivatives containing these compounds as a skeleton. Furthermore, polymers such as polythiophene, polyfluorene, polyphenylene vinylene, polytriallylamine, polyacetylene, polyaniline, polypyrrole and the like including poly (3-alkylthiophene) and the like are also included.

  The n-type semiconductor is not particularly limited, but specifically, a fullerene compound, a quinolinol derivative metal complex represented by 8-hydroxyquinoline aluminum; naphthalene tetracarboxylic acid anhydride; naphthalene tetracarboxylic acid diimide or perylene tetracarboxylic acid Condensed ring tetracarboxylic acid diimides such as acid diimides; perylene diimide derivatives, terpyridine metal complexes, tropolone metal complexes, flavonol metal complexes, perinone derivatives, benzimidazole derivatives, benzoxazole derivatives, thiazole derivatives, benzthiazol derivatives, benzothiadiazole derivatives, Oxadiazole derivatives, thiadiazole derivatives, triazole derivatives, aldazine derivatives, bisstyryl derivatives, pyrazine derivatives, phenanthroline derivatives, quinoxaline Conductor, benzoquinoline derivatives, bipyridine derivatives, borane derivatives, anthracene, pyrene, total fluoride condensed polycyclic aromatic hydrocarbons such as naphthacene or pentacene; single-walled carbon nanotubes, and the like.

  Among them, fullerene compounds, borane derivatives, thiazole derivatives, benzothiazole derivatives, benzothiadiazole derivatives, N-alkyl-substituted naphthalenetetracarboxylic acid diimides and N-alkyl-substituted perylene diimide derivatives are preferable, and fullerene compounds, N- Alkyl substituted perylene diimide derivatives and N-alkyl substituted naphthalene tetracarboxylic acid diimides are more preferred. One of the above compounds may be used, or a mixture of a plurality of compounds may be used. An n-type semiconductor is also included as an n-type semiconductor.

  The specific configuration of the organic photoelectric conversion layer is arbitrary as long as at least a p-type semiconductor and an n-type semiconductor are contained. The organic photoelectric conversion layer may be composed of only a single layer film or may be composed of two or more laminated films. For example, an n-type semiconductor and a p-type semiconductor may be contained in separate films, or an n-type semiconductor and a p-type semiconductor may be contained in the same film. In addition, each of the n-type semiconductor and the p-type semiconductor may be used alone or in combination of two or more in any combination and ratio.

  As a specific configuration example of the organic photoelectric conversion layer, a bulk heterojunction type having a layer (i layer) in which a p-type semiconductor and an n-type semiconductor are phase-separated in the layer, a layer (p layer) each including a p-type semiconductor, Examples include a stacked type (hetero pn junction type) in which a layer containing an n-type semiconductor (n layer) has an interface (Schottky type), a Schottky type, and a combination thereof. Among these, a bulk heterojunction type and a combination of a bulk heterojunction type and a stacked type (p-i-n junction type) are preferable because they exhibit high performance.

  Although there is no restriction | limiting in particular as a preparation method of an organic photoelectric converting layer, A coating method, especially a wet coating method is preferable. As the coating method, any method can be used, for example, spin coating method, reverse roll coating method, gravure coating method, kiss coating method, roll brush method, spray coating method, air knife coating method, wire barber coating method, Examples include the pipe doctor method, the impregnation / coating method, and the curtain coating method. In the case where the photoelectric conversion layer is formed by a roll-to-roll method, it is preferable to apply a wet coating method because the apparatus is simple, the cost is low, and the photoelectric conversion layer can be formed quickly in large quantities. When performing the wet coating method, it is preferable to select a solvent that does not dissolve the coating layer.

  The thickness of each of the p layer, i layer, and n layer of the organic photoelectric conversion layer is usually 3 nm or more, preferably 10 nm or more, more preferably 20 nm or more, still more preferably 30 nm or more, particularly preferably 50 nm or more, and usually 1000 nm or less. , Preferably 500 nm or less, more preferably 300 nm or less. Increasing the thickness tends to increase the photocurrent, and decreasing the thickness tends to decrease the series resistance. Moreover, by setting it as the thickness more than the said lower limit, when installing a collector line on a cell especially, the short circuit of the cell by installation of a collector line can be prevented.

1.2.3.4 Buffer Layer The organic thin film solar cell element according to the present invention may include a buffer layer between the lower electrode and / or the upper electrode and the organic photoelectric conversion layer. The buffer layer refers to an electron extraction layer and / or a hole extraction layer. The buffer layer is not essential in the organic thin film solar cell element according to the present invention, and may include only one of an electron extraction layer and a hole extraction layer. The electron extraction layer is preferably present between the cathode and the organic photoelectric conversion layer, and the hole extraction layer is preferably present between the anode and the organic photoelectric conversion layer.

  That is, the electron extraction layer and the hole extraction layer are preferably arranged so that the organic photoelectric conversion layer is sandwiched between the pair of electrodes. The stacking order of the electron extraction layer and the hole extraction layer may be appropriately selected as described above according to the functions of the upper electrode and the lower electrode, that is, each electrode is either an anode or a cathode.

Specifically, when the upper electrode is an anode and the lower electrode is a cathode and both the electron extraction layer and the hole extraction layer are included as buffer layers, the organic thin film solar cell element includes the lower electrode, the electron extraction layer, the photoelectric It is preferable to have a conversion layer, a hole extraction layer, and an upper electrode in this order. When the electron extraction layer is included and the hole extraction layer is not included, the organic thin film solar cell element preferably has a lower electrode, an electron extraction layer, a photoelectric conversion layer, and an upper electrode in this order. Similarly, when the hole extraction layer is included and the electron extraction layer is not included, the organic thin film solar cell element preferably has a lower electrode, a photoelectric conversion layer, a hole extraction layer, and an upper electrode in this order.
Further, at least one of the electron extraction layer and the hole extraction layer may be composed of a plurality of different layers.

[Electronic extraction layer]
The material of the electron extraction layer is not particularly limited as long as it is a material that improves the efficiency of extracting electrons from the organic photoelectric conversion layer to the cathode, and examples thereof include inorganic compounds and organic compounds.
Examples of the material of the inorganic compound include salts of alkali metals such as Li, Na, K or Cs; n-type semiconductor oxides such as titanium oxide (TiOx) and zinc oxide (ZnO). Among them, the alkali metal salt is preferably a fluoride salt such as LiF, NaF, KF or CsF, and the n-type semiconductor oxide is preferably zinc oxide (ZnO). Although the operation mechanism of such materials is unknown, it is possible to reduce the work function of the cathode when combined with a cathode made of Al or the like and increase the voltage applied to the organic thin film solar cell element. It is done.

  Examples of organic compound materials include, for example, phosphine compounds having a double bond between a phosphorus atom and a group 16 element such as triarylphosphine oxide compounds; bathocuproin (BCP) or bathophenanthrene (Bphen), A phenanthrene compound which may have a substituent and may be substituted at the 1-position and the 10-position with a heteroatom; a boron compound such as triarylboron; and (8-hydroxyquinolinato) aluminum (Alq3) Organometallic oxide; Compound having 1 or 2 ring structure which may have a substituent such as oxadiazole compound or benzimidazole compound; Naphthalenetetracarboxylic anhydride (NTCDA) or perylenetetracarboxylic acid Of dicarboxylic anhydrides, such as anhydrides (PTCDA) Aromatic compounds having Unachijimigo dicarboxylic acid structure.

  The thickness of the electron extraction layer is not particularly limited, but is usually 0.01 nm or more, preferably 0.1 nm or more, more preferably 0.5 nm or more. On the other hand, it is usually 400 nm or less, preferably 200 nm or less. When the thickness of the electron extraction layer is equal to or more than the above lower limit, the function as a buffer material is achieved. When the thickness of the electron extraction layer is not more than the above upper limit, electrons can be easily extracted and the photoelectric conversion efficiency can be improved.

  There is no restriction | limiting in the formation method of an electronic taking-out layer. For example, when a material having sublimation property is used, it can be formed by a vacuum deposition method or the like. Specifically, for example, when an alkali metal salt is used as a material for the electron extraction layer, the electron extraction layer can be formed by using a vacuum film formation method such as vacuum deposition or sputtering. Especially, it is desirable to form an electron taking-out layer by vacuum vapor deposition by resistance heating. By using vacuum deposition, damage to other layers such as a photoelectric conversion layer can be reduced.

  Further, for example, when using a material soluble in a solvent, the spin coating method, reverse roll coating method, gravure coating method, kiss coating method, roll brush method, spray coating method are used in the same manner as the method for producing the photoelectric conversion layer described above. It can be formed by a wet coating method such as an air knife coating method, a wire barber coating method, a pipe doctor method, an impregnation / coating method, a curtain coating method, or the like.

  On the other hand, for metal oxides of n-type semiconductors, for example, when zinc oxide ZnO is used as the material for the electron extraction layer, a vacuum film formation method such as sputtering can be used. It is desirable to form the extraction layer. For example, Sol-Gel Science, C.I. J. et al. Brinker, G.M. W. According to the sol-gel method described by Scherer, Academic Press (1990), an electron extraction layer composed of zinc oxide can be formed. In this case, the thickness is usually 0.1 nm or more, preferably 2 nm or more, more preferably 5 nm or more, and usually 1 μm or less, preferably 100 nm or less, more preferably 50 nm or less. If the electron extraction layer is too thin, the effect of improving the electron extraction efficiency is not sufficient, and if it is too thick, the electron extraction layer tends to deteriorate the characteristics of the device by acting as a series resistance component.

  In the case where the electron extraction layer is formed by a roll-to-roll method, it is preferable to apply a wet coating method because the apparatus is simple, the cost is low, and the electron extraction layer can be formed quickly in large quantities. When performing the wet coating method, it is preferable to select a solvent that does not dissolve the coating layer.

[Hole extraction layer]
The material for the hole extraction layer is not particularly limited as long as it is a material capable of improving the efficiency of extracting holes from the organic photoelectric conversion layer to the anode. Specifically, a conductive polymer in which polythiophene, polypyrrole, polyacetylene, triphenylenediamine, polyaniline or the like is doped with sulfonic acid and / or iodine, etc .; a conductive organic material such as a polythiophene derivative having a sulfonyl group as a substituent, arylamine or the like Compound: Metal oxide such as copper oxide, nickel oxide, manganese oxide, molybdenum oxide, vanadium oxide or tungsten oxide; Nafion, p-type semiconductor described later, and the like. Among them, a conductive polymer doped with sulfonic acid is preferable, and (3,4-ethylenedioxythiophene) poly (styrenesulfonic acid) (PEDOT: PSS) in which a polythiophene derivative is doped with polystyrene sulfonic acid is more preferable. It is. A thin film of metal such as gold, indium, silver or palladium can also be used. A thin film of metal or the like may be formed alone or in combination with the above organic material.

  The thickness of the hole extraction layer is not particularly limited, but is usually 0.2 nm or more. On the other hand, it is usually 400 nm or less, preferably 200 nm or less. When the thickness of the hole extraction layer is 0.2 nm or more, it functions as a buffer material. When the thickness of the hole extraction layer is 400 nm or less, holes can be easily extracted and the photoelectric conversion efficiency can be improved.

  There is no restriction | limiting in the formation method of a positive hole taking-out layer. For example, when a material having sublimation property is used, it can be formed by a vacuum deposition method or the like. For example, when using a material soluble in a solvent, a spin coating method, a reverse roll coating method, a gravure coating method, a kiss coating method, a roll brush method, a spray coating method, an air knife coating method, a wire barber coating method, a pipe doctor It can be formed by a wet coating method such as a method, an impregnation / coating method, or a curtain coating method. The hole extraction layer is preferably formed by coating. When a semiconductor material is used for the hole extraction layer, the precursor may be converted into a semiconductor compound after the layer is formed using the precursor, similarly to the low-molecular organic semiconductor compound of the organic photoelectric conversion layer described later.

  Especially, when using PEDOT: PSS as a material of a hole taking-out layer, it is preferable to form a hole taking-out layer by the method of apply | coating a dispersion liquid. Examples of the dispersion of PEDOT: PSS include CLEVIOSTM series manufactured by Heraeus, ORGACONTM series manufactured by Agfa, and the like.

  When the hole extraction layer is formed by a roll-to-roll method, it is preferable to apply a wet coating method because the apparatus is simple, the cost is low, and the hole extraction layer can be formed quickly in large quantities. When performing the wet coating method, it is preferable to select a solvent that does not dissolve the coating layer.

1.2.4 Adhesive layer The organic thin-film solar cell module of the present invention preferably has an adhesive layer for installation on a window glass. The adhesive layer is located on the outermost layer of the organic thin film solar cell module, and is a layer for adhering the organic thin film solar cell module to a construction object such as glass.

As the adhesive layer, a known transparent adhesive can be used. For example, acrylic adhesives, polyester adhesives, rubber adhesives, silicone adhesives, polyurethane adhesives and the like can be mentioned. Among these, acrylic adhesive materials are preferable from the viewpoint of weather resistance.
The adhesive layer can be provided by a known method on the outermost layer on the light receiving surface or non-light receiving surface side of the solar cell module. For example, it can be provided by providing an adhesive on release paper, dry laminating on the outermost layer of the organic thin film solar cell module, and then peeling the release paper.

  It is preferable that the adhesive layer has sufficient adhesive force and adhesive force so that the glass does not scatter when the window glass is broken. Specifically, a method having a peeling force of about 4.0 N / 25 mm or more can be used by the method shown in JIS A5759.

  The thickness of the pressure-sensitive adhesive layer is, for example, usually 30 μm or more, preferably 50 μm or more, more preferably 100 μm or more, and usually 300 μm, preferably 200 μm or less, more preferably 150 μm or less. Sufficient adhesiveness is ensured by being more than the said minimum, and the water residue after construction is reduced. By being below the above upper limit, it becomes easy to squeegee when installing on a construction object such as a window glass.

1.2.5 Other Layers A protective layer, an ultraviolet cut layer, a getter layer, and the like may be provided on the gas barrier layer, between the gas barrier layer and the sealing layer, and between the gas barrier layer and the adhesive layer. These layers can also be used as a gas barrier layer.

[Protective layer (surface protective layer and back surface protective layer)]
The protective layer is a layer that protects the organic thin-film solar cell module from an installation environment such as temperature change, humidity change, light, and wind and rain. By covering the surface of the organic thin film solar cell module with the protective layer, the constituent material of the organic thin film solar cell module, in particular, the organic thin film solar cell element is protected, and there is an advantage that high power generation capability can be obtained without deterioration. is there.

  Since the protective layer is located on the outermost layer of the organic thin film solar cell module, it is suitable as a surface covering material for the organic thin film solar cell module such as weather resistance, heat resistance, transparency, water repellency, contamination resistance, mechanical strength, etc. It is preferable to have performance and to maintain it for a long period of time in outdoor exposure.

  Moreover, when a protective layer is used for the light-receiving surface side of a thin film solar cell element, it is preferable to transmit visible light from the viewpoint of preventing light absorption. For example, the transmittance of visible light (wavelength 360 to 830 nm) is usually 75% or more, preferably 80% or more, more preferably 85% or more, further preferably 90% or more, and particularly preferably 95% or more. Particularly preferably, it is 97% or more. This is to convert more sunlight into electrical energy.

  Further, the protective layer preferably has a low haze from the viewpoint of design properties such as a sense of unity with the construction object and appearance. For example, the haze value when using a D65 light source defined by JIS K 7136 is usually 10 or less, preferably 5 or less, more preferably 2 or less, and even more preferably 1 or less.

  On the other hand, the protective layer on the surface opposite to the light receiving surface of the organic thin film solar cell element does not necessarily need to transmit visible light and may be opaque, but when pasted on a transparent construction object such as a window glass, It is preferable to have the same visible light transmittance and haze as the light receiving surface side of the organic thin film solar cell element.

  Furthermore, since the organic thin film solar cell module is often heated by receiving light, the protective layer preferably has resistance to heat. From this viewpoint, the melting point of the constituent material of the protective layer is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and usually 350 ° C. or lower, preferably 320 ° C. or lower, more preferably 300 It is below ℃. By increasing the melting point, it is possible to reduce the possibility that the protective layer melts and deteriorates when the organic thin film solar cell element is used.

  The material which comprises a protective layer is arbitrary as long as it can protect an organic thin film solar cell module. Examples of the material include polyethylene resin, polypropylene resin, cyclic polyolefin resin, AS (acrylonitrile-styrene) resin, ABS (acrylonitrile-butadiene-styrene) resin, polyvinyl chloride resin, fluorine resin, polyethylene terephthalate, polyethylene Examples thereof include polyester resins such as naphthalate, phenol resins, polyacrylic resins, polyamide resins such as various nylons, polyimide resins, polyamide-imide resins, polyurethane resins, cellulose resins, silicone resins, and polycarbonate resins.

  Among them, fluorine resin is preferable, and specific examples thereof include polytetrafluoroethylene (PTFE), 4-fluoroethylene-perchloroalkoxy copolymer (PFA), 4-fluoroethylene-6-fluoride. Propylene copolymer (FEP), 2-ethylene-4-fluoroethylene copolymer (ETFE), poly-3-fluoroethylene chloride (PCTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), etc. Can be mentioned.

Note that the protective layer may be formed of one kind of material or may be formed of two or more kinds of materials. The protective layer may be formed as a single layer, but may be a laminate including two or more layers.
The thickness of the protective layer is not particularly defined, but is usually 10 μm or more, preferably 15 μm or more, more preferably 20 μm or more, and usually 200 μm or less, preferably 180 μm or less, more preferably 150 μm or less. Increasing the thickness tends to increase mechanical strength, and decreasing the thickness tends to increase flexibility. For this reason, it is desirable to set it as the said range as a range which has both advantages.

Further, the protective layer may be subjected to surface treatment such as corona treatment or plasma treatment in order to improve adhesion with other layers.
The protective layer is preferably provided on the outer side of the organic thin film solar cell module as much as possible. This is so that more of the organic thin film solar cell modules can be protected.

  In addition, the protective layer has ultraviolet blocking, heat blocking, antifouling, hydrophilic, hydrophobic, antifogging, abrasion resistance, conductivity, antireflection, antiglare, light diffusion, light scattering, wavelength conversion, gas barrier properties Such functions may be given. In particular, the organic thin film solar cell is preferably exposed to strong ultraviolet rays from sunlight, and therefore has an ultraviolet blocking function.

  As a method for imparting such a function, a layer having a function may be laminated on the protective layer by coating film formation or the like, or a material that exhibits a function may be dissolved and dispersed to be contained in the protective layer. May be.

  In addition, the protective layer is hard-coated to prevent scratches when handling organic thin-film solar cell modules, to prevent scratches due to squeegees when applying water to construction objects, and to improve the smoothness of the protective layer. A layer may be provided.

  As the hard coat layer, conventionally known ones can be used, such as an ultraviolet curable resin; an electron beam curable resin; an alkoxysilane hydrolytic condensation resin; a melamine resin; a (meth) acrylate alcohol-modified polyfunctional compound; Examples include layers made of acrylic resins such as methylolpropane (meth) acrylate, tripropylene glycol diacrylate, pentaerythritol triacrylate, 1,6 hexanediol (meth) acrylate, but are not limited thereto. The hard coat layer preferably has a pencil hardness of 2H or higher, more preferably 3H or higher. Moreover, it is preferable that the film thickness is 1-10 micrometers. If it is less than 1 μm, the effect of scratch resistance may not be sufficient, and if it is 10 μm or more, the protective layer may curl due to curing shrinkage of the hard coat layer.

[UV cut layer]
The ultraviolet cut layer is a layer that prevents transmission of ultraviolet rays.
Some components of the organic thin film solar cell module are deteriorated by ultraviolet rays. Some gas barrier layers are deteriorated by ultraviolet rays depending on the type. Therefore, an ultraviolet cut layer is provided in the light receiving portion of the organic thin film solar cell module, and the organic thin film solar cell element and, if necessary, the gas barrier layer are protected from ultraviolet rays by covering the light receiving surface of the organic thin film solar cell element with the ultraviolet cut layer. In addition, the power generation performance can be maintained high.

  The degree of the ability to suppress the transmission of ultraviolet rays required for the ultraviolet cut layer is such that the transmittance of ultraviolet rays (for example, wavelength of 300 nm) is preferably 50% or less, more preferably 30% or less, and particularly preferably 10 % Or less.

  In addition, the ultraviolet cut layer is preferably one that transmits visible light from the viewpoint of not hindering light absorption of the organic thin film solar cell element. For example, the transmittance of visible light (wavelength 360 to 830 nm) is preferably 80% or more, more preferably 90% or more, and particularly preferably 95% or more.

  Further, since the organic thin film solar cell module is often heated by receiving light, it is preferable that the ultraviolet cut layer also has heat resistance. From this viewpoint, the melting point of the constituent material of the ultraviolet cut layer is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 130 ° C. or higher. Moreover, it is 350 degrees C or less normally, Preferably it is 320 degrees C or less, More preferably, it is 300 degrees C or less. If the melting point is too low, there is a possibility that the ultraviolet cut layer melts when the organic thin film solar cell module is used.

In addition, the ultraviolet cut layer is preferably highly flexible, has good adhesion with an adjacent layer, and can cut water vapor and oxygen.
The material constituting the ultraviolet cut layer is arbitrary as long as it can weaken the intensity of ultraviolet rays. Examples of the material include a layer formed by blending an ultraviolet absorber with an epoxy resin, an acrylic resin, a urethane resin, or an ester resin. Moreover, you may use as a laminated body which formed the layer (henceforth an "ultraviolet absorption layer" suitably) of what disperse | distributed or melt | dissolved the ultraviolet absorber in resin on the base film.

As the ultraviolet absorber, for example, salicylic acid-based, benzophenone-based, benzotriazole-based, and cyanoacrylate-based ones can be used. Of these, benzophenone and benzotriazole are preferable. Examples of this include various aromatic organic compounds such as benzophenone and benzotriazole. In addition, a ultraviolet absorber may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.
As an example of a specific product of the ultraviolet cut layer, cut ace (MKV Plastic Co., Ltd.) and the like can be given.

In addition, the ultraviolet cut layer may be formed of one type of material or may be formed of two or more types of materials. Further, the ultraviolet cut layer may be a single layer or a multilayer of two or more layers.
The thickness of the ultraviolet cut layer is not particularly defined, but is usually 5 μm or more, preferably 10 μm or more, more preferably 15 μm or more. Moreover, it is 200 micrometers or less normally, Preferably it is 180 micrometers or less, More preferably, it is 150 micrometers or less. Increasing the thickness tends to increase the absorption of ultraviolet rays, and decreasing the thickness tends to increase the transmittance of visible light.

  What is necessary is just to provide an ultraviolet-ray cut layer in the position which covers at least one part of the light-receiving surface of an organic thin-film solar cell element. Preferably, it is better to provide in a region covering the entire light receiving surface of the organic thin film solar cell element. However, the ultraviolet cut layer may be provided in a region other than the region covering the light receiving surface of the organic thin film solar cell element.

[Getter layer]
The getter layer is a layer that absorbs moisture and / or oxygen. Some of the constituent members of the organic thin film solar cell element are deteriorated by moisture as described above, and some are deteriorated by oxygen. Therefore, by covering the organic thin film solar cell element with a getter layer, the organic thin film solar cell element and the like are protected from moisture and / or oxygen, and the power generation performance is kept high.

  Here, unlike the gas barrier layer as described above, the getter layer does not prevent the permeation of moisture and / or oxygen but absorbs moisture and / or oxygen. When the organic thin-film solar cell module has a layer that absorbs moisture and / or oxygen, when the organic thin-film solar cell element is covered with a gas barrier layer or the like, moisture and / Alternatively, oxygen can be captured by the getter layer and the influence of moisture on the organic thin film solar cell element can be eliminated.

The degree of water absorption capacity of the getter layer is usually 0.1 mg / cm ² or more, preferably 0.5 mg / cm ² or more, more preferably 1 mg / cm ² or more. The higher this value, the higher the water absorption capacity, and the deterioration of the organic thin film solar cell element can be suppressed. Moreover, although there is no restriction | limiting in an upper limit, it is usually 10 mg / cm < ² > or less.

  Further, the getter layer is preferably one that transmits visible light from the viewpoint of not hindering light absorption of the organic thin film solar cell element. For example, the transmittance of visible light (wavelength 360 to 830 nm) is usually 60% or more, preferably 70% or more, more preferably 75% or more, still more preferably 80% or more, and particularly preferably 85% or more. Preferably it is 90% or more, Especially preferably, it is 95% or more, Especially preferably, it is 97% or more. This is to convert more sunlight into electrical energy.

  Furthermore, since the organic thin film solar cell module is often heated by receiving light, it is preferable that the getter layer also has heat resistance. From this viewpoint, the melting point of the constituent material of the getter layer is usually 100 ° C. or higher, preferably 120 ° C. or higher, more preferably 130 ° C. or higher, and usually 350 ° C. or lower, preferably 320 ° C. or lower, more preferably 300 ° C. It is below ℃. By increasing the melting point, it is possible to reduce the possibility that the getter layer will melt and deteriorate when the organic thin film solar cell module is used.

  The material constituting the getter layer is arbitrary as long as it can absorb moisture and / or oxygen. Examples of the material include alkali metal, alkaline earth metal or alkaline earth metal oxides; alkali metal or alkaline earth metal hydroxides; silica gel, zeolitic compounds, magnesium sulfate. And sulfates such as sodium sulfate and nickel sulfate; and organometallic compounds such as aluminum metal complexes and aluminum oxide octylates. Specifically, examples of the alkaline earth metal include Ca, Sr, and Ba. Examples of the alkaline earth metal oxide include CaO, SrO, and BaO. In addition, Zr-Al-BaO and aluminum metal complexes are also included. Specific product names include, for example, OleDry (Futaba Electronics).

Examples of the substance that absorbs oxygen include activated carbon, silica gel, activated alumina, molecular sieve, magnesium oxide, and iron oxide. In addition, Fe, Mn, Zn, and inorganic salts such as sulfates, chlorides, and nitrates of these metals are also included.
Note that the getter layer may be formed of one kind of material or may be formed of two or more kinds of materials. In addition, the getter layer may be formed as a single layer, but may be a laminate including two or more layers.

  The thickness of the getter layer is not particularly limited, but is usually 5 μm or more, preferably 10 μm or more, more preferably 15 μm or more, and usually 200 μm or less, preferably 180 μm or less, more preferably 150 μm or less. Increasing the thickness tends to increase mechanical strength, and decreasing the thickness tends to increase flexibility.

  The formation position of the getter layer is not limited as long as it is in the space formed between the gas barrier layers. However, both surfaces of the thin film solar cell element, specifically, as shown in FIG. It is preferable to cover the surface opposite to the light receiving surface. In organic thin-film solar cell modules, the surface on the light-receiving surface side and the surface opposite to the light-receiving surface side are often formed in a larger area than the other surfaces, so moisture and oxygen enter through these surfaces. Because there is a tendency to. From this viewpoint, the getter layer is preferably provided between the gas barrier layer and the thin film solar cell element.

  The getter layer can be formed by any method depending on the type of the water-absorbing agent or desiccant. For example, a method of attaching a film in which the water-absorbing agent or desiccant is dispersed with an adhesive, a solution of the water-absorbing agent or the desiccant The method etc. which apply | coat this by a spin coat method, the inkjet method, or a dispenser method etc. can be used. Further, a film forming method such as a vacuum evaporation method or a sputtering method may be used.

  Examples of the film in which the water-absorbing agent or the desiccant is dispersed include, for example, polyethylene resins, polypropylene resins, cyclic polyolefin resins, polystyrene resins, acrylonitrile-styrene copolymers (AS resins), and acrylonitrile-butadiene-styrene copolymers. (ABS resin), polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, or the like can be used. Among these, a film of polyethylene resin, fluorine resin, cyclic polyolefin resin or polycarbonate resin is preferable. In addition, the said resin may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

1.2.6 Current collector 3
A general organic thin film solar cell module usually has a current collector for taking out electricity from the solar cell element. The structure of the current collector is preferably a structure in which a conductive layer 31 and a conductive adhesive layer 32 are laminated.
The material for the conductive layer is preferably a metal or an alloy, and more preferably copper, aluminum, silver, gold, nickel or the like having a low resistivity. Copper and aluminum are particularly preferable because they are inexpensive. In order to prevent rust, the current collector may be plated with tin, silver or the like, the surface may be coated with resin, or a film may be laminated.

As the shape of the current collecting wire, there are a rectangular wire, foil, flat plate, and wire shape, but for reasons such as securing a bonding area, it is preferable to use a flat wire, foil, or flat plate shape.
Here, “foil” means a material having a thickness of less than 100 μm, and “plate” means a material having a thickness of 100 μm or more. Further, the “flat wire” refers to a wire whose cross section is rolled to make the cross section into a quadrangle.

  The current collector is not particularly limited as long as it has conductivity, but preferably has a lower electrical resistance value than the upper electrode and lower electrode to be connected, and in particular, by increasing the thickness of the upper electrode and lower electrode. It is preferable to reduce the electric resistance value. The thickness of the current collector is preferably 5 μm or more, more preferably 10 μm or more. Moreover, it is preferable that it is 2 mm or less, More preferably, it is 1 mm or less, More preferably, it is 300 micrometers or less, Most preferably, it is 200 micrometers or less. If the thickness is smaller than the above range, the resistance value of the current collector increases, and the generated power may not be efficiently taken out to the outside. Moreover, if the thickness is larger than the above range, the organic thin-film solar cell module increases in weight and has a problem that flexibility is reduced, irregularities are easily generated on the module surface, and production costs are increased. May occur.

  The width of the current collector is preferably 0.5 mm or more, more preferably 1 mm or more, and particularly preferably 2 mm or more. Moreover, it is preferable that the width | variety of a current collection line is 50 mm or less, More preferably, it is 20 mm or less, Most preferably, it is 10 mm or less. If the width of the current collection line is narrower than the above range, the electrical resistance value of the current collection line will increase, and the generated power may not be taken out efficiently. In addition, the mechanical strength of the current collector decreases, which may cause breakage and the like. Moreover, when the width | variety of a current collection line is wider than the said range, the aperture ratio in the whole module will reduce, and there exists a possibility of leading to the fall of the power generation amount of a module.

  In addition, the shape of the current collector line can be embossed. The embossed shape means a shape formed by embossing some uneven shape. By forming the current collector in an embossed shape, even if an adhesive layer is used, a portion of the embossed unevenness can be in direct contact with or very close to the electrode, so that conductivity is increased.

  The embossing depth is usually 5 to 100 μm, and preferably 10 to 50 μm. The emboss depth means the height of the convex portion formed by embossing, and is specifically a value obtained by subtracting the thickness of the current collector from the thickness including the convex portion. Such an embossing depth is preferable because the embossed convex portion can directly contact the electrode.

The current collector is connected to the electrode through the conductive adhesive layer. As a conductive adhesive component to be installed on an electrode of an organic thin-film solar cell element, a thermosetting composition containing conductive particles, a thermoplastic plastic containing conductive particles, solder, a metal paste, and the like are known. The conductive adhesive layer can be used. The thickness of the conductive adhesive layer is usually 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, further preferably 20 μm or more, and usually 500 μm or less, preferably 300 μm or less, more preferably 100 μm or less, more preferably 50 μm. It is as follows. By being below the above upper limit, the current collector can be made thin, the organic thin film solar cell module is difficult to contain bubbles, and the workability of the organic thin film solar cell module is preferable. It is preferable that it is at least the above lower limit in terms of high connection reliability between the current collector and the organic thin film solar cell element.
As described above, any of the current collection line and the first gas barrier layer may be installed in the organic thin film solar cell element first.

2. Construction method of organic thin film solar cell module The construction method of the organic thin film solar cell module can be arbitrarily selected according to the work piece, but the organic thin film solar cell module of the present invention is used as an organic thin film solar cell module for sticking construction. It can use suitably, In that case, it can construct by the method similar to a general film.

  A general film is stuck on glass by a method called water sticking. This method of sticking with water is to stick the film on the glass with a sprayer sprayed with water containing a small amount of neutral detergent on the adhesive surface and glass surface of the film, and then squeegee the film surface sequentially. Rub evenly to adhere. As a result, water and air bubbles between the film and the glass are expelled from the end of the film, and a good bonding surface free from wrinkles and air bubbles can be obtained.

3. Applications The organic thin film solar cell module of the present invention can be used by being attached to a construction object such as glass such as a partition, glass such as a window, a door, a wall surface, or a ceiling, such as a building or a vehicle. At this time, power is generated using sunlight, indoor lighting, indoor sunlight scattered light, etc., and the electric power taken out from the current collector is charged and used using a known current-voltage conversion circuit, storage battery, etc. be able to. In particular, the organic thin film solar cell module of the present invention is excellent in handleability, workability, and design as an organic thin film solar cell module for sticking construction.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to a following example.

[Evaluation method]
In this example, the organic thin film solar cell module was evaluated by the following method.

[Workability]
The surface of the float glass having a thickness of 3.2 mmt, a length of 1800 mm, and a width of 1000 mm is washed twice to three times with an aqueous solution of a neutral detergent obtained by diluting the surface 100 to 200 times. Spray. Remove the adhesive layer release film from the solar cell integrated film and spray it onto the entire neutral detergent solution, which is also diluted 100 to 200 times. Fix it and spray it onto the surface of the solar cell integrated film. Pressurized with a nylon squeegee, extruded water multiple times to the top, bottom, left, and right ends and applied to the target float glass. The installed module was visually checked for the presence of water bubbles.

○: Visual inspection after construction without water bubbles and good construction appearance ×: Water bubbles generated by visual inspection after construction

[Construction resistance]
The prepared organic thin film solar cell module was attached with water by squeegee construction, and then the EL light emission of the organic thin film solar cell element was evaluated using a solar cell EL inspection device manufactured by ITES.
○: There is no change in the initial EL light emission image of the organic thin film solar cell element and the EL light emission image after squeegee. ×: The initial EL light emission image of the organic thin film solar cell element is compared with the EL light emission image after the squeegee. An EL non-light emitting part is generated

[Module appearance]
The organic thin film solar cell module was applied to a float glass having a thickness of 3.2 mm, a length of 1800 mm, and a width of 1000 mm, and the visual appearance after the operation and the EL image of the organic thin film solar cell element were measured. The presence or absence of breakage of the battery element was evaluated.

<Example 1>
As a pre-preparation before stacking, on the upper electrode of the organic thin-film solar battery cell at both ends of the organic thin-film solar battery element, a collector wire with a conductive thermosetting resin composition (DT101C4 manufactured by Dexerials, Inc. (nickel particles as conductive particles) Epoxy conductive curable resin containing, curing temperature 120 ° C.) 15 μm + copper foil thickness 35 μm, width 4 mm).

  In addition, a 0.1 mm thick barrier film (Mitsubishi Resin, VIEW-BARRIER) is laminated as a first gas barrier layer, and a 0.06 mm thick epoxy-based sealing material (Three Bond Co., Ltd.) is laminated as a first sealing layer. A laminated body having a length of 1000 mm and a width of 500 mm, a thickness of 0.12 mm, a length of 150 mm and a width of 100 mm, and a barrier film (Mitsubishi Resin, VIEW- BARRIER) and a laminate of 0.06 mm thick epoxy sealing material (manufactured by ThreeBond Co., Ltd.) having a thickness of 0.06 mm as a second sealing layer, the second sealing layer is the organic thin film solar cell element. Was placed in contact with each other and placed in a vacuum laminator (NLM-270 × 400, manufactured by NPC). First, the inside of the laminator was held under reduced pressure for 15 minutes, and then the laminate was held at 80 ° C. for 10 minutes while being brought into a pressure-bonded state at atmospheric pressure to obtain an organic thin film solar cell module. A commercially available acrylic adhesive having a thickness of 0.12 mm was bonded to the second gas barrier layer of the organic thin film solar cell module with a roll laminator (MCK, MRS630A) to produce an organic thin film solar cell module having an adhesive layer.

<Example 2>
The first and second gas barrier layers are 0.06 mm thick barrier films (Mitsubishi Resin, VIEW-BARRIER), and the first and second sealing layers are 0.03 mm thick epoxy-based sealing materials (manufactured by ThreeBond Co., Ltd.). Except for the above, an organic thin-film solar cell module having an adhesive layer was obtained in the same manner as in Example 1.

<Comparative Example 1>
Example, except that the first and second gas barrier layers were 0.05 mm thick barrier films, and the first and second sealing layers were 0.03 mm thick epoxy-based sealing materials (manufactured by Three Bond Co., Ltd.). As in Example 1, an organic thin-film solar cell module having an adhesive layer was obtained.

<Comparative example 2>
As in Example 1, except that the first and second gas barrier layers were 0.05 mm thick barrier films, and the first and second sealing layers were 0.15 mm thick olefin-based encapsulants. An organic thin film solar cell module having an adhesive layer was obtained.

<Comparative Example 3>
As in Example 1, except that the first and second gas barrier layers were 0.015 mm thick barrier films, and the first and second sealing layers were 0.08 mm thick epoxy-based encapsulants. An organic thin film solar cell module having an adhesive layer was obtained.

<Comparative example 4>
Other than the first and second gas barrier layers being 0.1 mm thick barrier films (Mitsubishi Resin, VIEW-BARRIER), and the first and second sealing layers being 0.015 mm thick epoxy-based sealing materials Obtained the organic thin-film solar cell module which has an adhesion layer similarly to Example 1. FIG.

<Comparative Example 5>
The adhesive layer is the same as in Example 1, except that the first and second gas barrier layers are 0.2 mm thick barrier films, and the first and second sealing layers are 0.1 mm thick sealing materials. An organic thin film solar cell module having

<Comparative Example 6>
A commercially available acrylic pressure-sensitive adhesive having a thickness of 0.03 mm was bonded to the second gas barrier layer of the solar cell film 1 with a roll laminator (manufactured by MCK, MRS630A) to obtain a solar cell integrated wind film 1. Except that, an organic thin film solar cell module having an adhesive layer was obtained in the same manner as in Example 1.

<Comparative Example 7>
A commercially available acrylic pressure-sensitive adhesive having a thickness of 0.35 mm was bonded to the second gas barrier layer of the solar cell film 1 with a roll laminator (manufactured by MCK, MRS630A) to obtain a solar cell integrated wind film 1. Except that, an organic thin film solar cell module having an adhesive layer was obtained in the same manner as in Example 1.

  In Table 1, the evaluation result of the organic thin film solar cell module of Examples 1, 2 and Comparative Examples 1-7 is shown.

表１より、本発明の有機薄膜太陽電池モジュールは施工作業中に太陽電池素子が破損しづらく、スキージの際の施工性が高いため施工後に有機薄膜太陽電池モジュールと被設置体との間の水泡が少なく、意匠性の高い有機薄膜太陽電池モジュールを提供することができることがわかる。

From Table 1, the organic thin-film solar cell module of the present invention is difficult to damage the solar cell element during construction work, and the workability at the time of squeegee is high, so water bubbles between the organic thin-film solar cell module and the installation object after construction. It can be seen that an organic thin-film solar cell module with a small amount of design and high designability can be provided.

DESCRIPTION OF SYMBOLS 11 1st gas barrier layer 12 2nd gas barrier layer 21 1st sealing layer 22 2nd sealing layer 3 Current collector 31 Conductive layer 32 Conductive adhesive layer 4 Organic thin film solar cell element 42 Element substrate 5 Adhesive layer

Claims (4)

The organic thin film solar cell module which has a 1st gas barrier layer, a 1st sealing layer, an organic thin film solar cell element, a 2nd sealing layer, and a 2nd gas barrier layer in order, and satisfy | fills the following conditions 1-3.
Condition 1: The ratio of the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer to the sum of the thicknesses of the first gas barrier layer and the second gas barrier layer is 0.36 or more. Condition 2: the first gas barrier layer The ratio of the sum of the thicknesses of the first sealing layer and the second sealing layer to the sum of the thicknesses of the gas barrier layer and the second gas barrier layer is 0.1 or more. Condition 3: The first gas barrier layer to the The ratio of the sum of the first gas barrier layer, the first sealing layer, the second sealing layer, and the second gas barrier layer to the sum of the thicknesses of the second gas barrier layers is 0.8 or less.   The organic thin-film solar cell module according to claim 1, further comprising an adhesive layer outside the first gas barrier layer or the second gas barrier layer. It is an organic thin film solar cell module of Claim 2, Comprising: The organic thin film solar cell module which satisfy | fills the following conditions 4.
Condition 4: The ratio of the thickness of the adhesive layer to the sum of the thicknesses of the first gas barrier layer to the second gas barrier layer and the adhesive layer is 0.05 or more and 0.35 or less.   The organic thin film solar cell module according to any one of claims 1 to 3, wherein a sum of thicknesses of the first gas barrier layer to the second gas barrier layer is 290 µm or more and 700 µm or less.

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