Gas barrier film and photoelectric conversion device

Abstract

Provided are a gas barrier film capable of preventing transmission of ultraviolet light of 380 nm or less, and a photoelectric conversion device equipped with this gas barrier film. According to an embodiment, there is provided a gas barrier film 1 including a substrate 2 and a first layer 3 provided on at least one surface 2a of the substrate 2. The gas barrier film 1 has a blocking ability against ultraviolet light with a wavelength of 380 nm or less.

Description

[Technical Field]

[0001] FIELD OF THE INVENTION The present invention relates to a gas barrier film and a photoelectric conversion device. [Background technology]

[0002] Gas barriers are widely used in applications such as electronic devices and packaging. For example, water vapor barriers are used in photoelectric conversion elements such as perovskite solar cells and organic electroluminescence (organic EL) elements, and nonaqueous electrolyte batteries. In food and pharmaceutical packaging, oxygen barriers are used to prevent deterioration of the contents. Known gas barrier films include those containing a silicon oxide film as a gas barrier layer, which is obtained by modifying a silicon compound such as polysilazane in an oxidizing atmosphere.

[0003] On the other hand, solar cells that use perovskite-type materials as photoelectric conversion materials have issues with light durability. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-137710 [Non-patent literature]

[0005] [Non-Patent Document 1] Solution-Processed Gas Barriers with Glass-Like Ultrahigh Barrier Performance by Tatsuki Sasaki et al., Advanced Materials Interfaces 2022, 9, 2201517 Summary of the Invention [Problem to be solved by the invention]

[0006] Provided are a gas barrier film capable of preventing transmission of ultraviolet light of 380 nm or less, and a photoelectric conversion device equipped with this gas barrier film. [Means for solving the problem]

[0007] According to an embodiment, there is provided a gas barrier film including a substrate and a first layer provided on at least one side of the substrate, The gas barrier film has a blocking ability against ultraviolet light having a wavelength of 380 nm or less.

[0008] According to an embodiment, there is also provided a photoelectric conversion device including a photoelectric conversion element and the gas barrier film of the embodiment provided on the photoelectric conversion element. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic cross-sectional view showing a first example of a gas barrier film according to an embodiment. [Figure 2] FIG. 3 is a schematic cross-sectional view showing a second example of a gas barrier film according to an embodiment. [Figure 3] FIG. 4 is a schematic cross-sectional view showing a third example of a gas barrier film according to an embodiment. [Figure 4] FIG. 1 is a schematic cross-sectional view showing a first example of a photoelectric conversion device according to an embodiment. [Figure 5] FIG. 4 is a schematic cross-sectional view showing a second example of a photoelectric conversion device according to an embodiment. [Figure 6] FIG. 10 is a schematic cross-sectional view showing a third example of a photoelectric conversion device according to an embodiment. [Figure 7] 1 is a graph showing the change in light transmittance when the wavelength of light is changed for the gas barrier film of the example. DETAILED DESCRIPTION OF THE INVENTION

[0010] (First embodiment) The gas barrier film of the first embodiment includes a substrate and a first layer provided on at least one side of the substrate. The gas barrier film has a blocking ability against ultraviolet rays with wavelengths of 380 nm or less. The blocking ability against ultraviolet rays with wavelengths of 380 nm or less may be achieved by absorbing the ultraviolet rays or by scattering the ultraviolet rays.

[0011] The first layer may be a single layer or may comprise multiple films.

[0012] The first layer may be, for example, a gas barrier layer. The gas barrier layer may be, for example, a silicon nitride film (SiN x (x>0) film) or silicon nitride (SiN x (x>0)) (hereinafter referred to as material film). Examples of silicon nitride films include those obtained by modifying a polysilazane compound with vacuum ultraviolet light in an N2 atmosphere, and those formed by chemical vapor deposition. The first layer may have a blocking ability against ultraviolet light with a wavelength of 380 nm or less. In this case, at least one of the silicon nitride film and the material film has a blocking ability against ultraviolet light with a wavelength of 380 nm or less.

[0013] The first layer does not have to have the ability to block ultraviolet rays with wavelengths of 380 nm or less. In this case, it is desirable to provide the first layer on one side of the substrate and the second layer with the ability to block ultraviolet rays with wavelengths of 380 nm or less on the other side of the substrate.

[0014] Examples of gas barrier films according to embodiments will be described with reference to FIGS. 1 to 3. The gas barrier layer of the gas barrier film shown in each figure comprises multiple layers. In each figure, the thickness direction of the gas barrier film is parallel to the z-axis direction. The surface direction of the gas barrier film is parallel to a plane defined by the x-axis and y-axis directions. The x-axis, y-axis, and z-axis directions intersect perpendicularly to one another. Furthermore, in each figure, components that are common to multiple figures are designated by the same reference numerals, and their description will be omitted.

[0015] The gas barrier films shown in FIGS. 1 and 2 are examples in which the first layer is a gas barrier layer having a blocking ability against ultraviolet rays with a wavelength of 380 nm or less.

[0016] The gas barrier film 1 shown in FIG. 1 includes a substrate 2 and a first layer 3 serving as a gas barrier layer. The first layer 3 includes a plurality of silicon nitride films. The substrate 2 has a layer or film shape. The substrate 2 has two main surfaces (principal surfaces) 2a and 2b that intersect in the thickness direction (z-axis direction). Each of the surfaces 2a and 2b is parallel to the xy plane. It can also be said that one surface 2a is located on the opposite side of the other surface 2b. The substrate 2 may be optically transparent. The substrate 2 may be formed from, for example, polyethylene terephthalate (PET), polycarbonate, ETFE (ethylene tetrafluoroethylene), PI (polyimide), PEN (polyethylene naphthalate), or the like. The substrate 2 may be made of one or more materials.

[0017] The first layer 3 is provided on one surface 2a of the substrate 2. In FIG. 1, the first layer 3 is laminated on one surface 2a of the substrate 2. The first layer 3 has barrier properties against gases such as water vapor and oxygen. The first layer 3 also has blocking properties against ultraviolet rays with wavelengths of 380 nm or less. The first layer 3 essentially consists of, for example, a silicon nitride film 4 on the substrate side and a silicon nitride film 5 on the surface side. The silicon nitride film 4 on the substrate side and the silicon nitride film 5 on the surface side each have two main surfaces (principal surfaces) that intersect with the thickness direction (z-axis direction). Each surface is parallel to the xy plane. At least one of the silicon nitride film 4 on the substrate side and the silicon nitride film 5 on the surface side needs to have blocking properties against ultraviolet rays with wavelengths of 380 nm or less. In FIG. 1, the silicon nitride film 5 on the surface side is assumed to have blocking properties against ultraviolet rays with wavelengths of 380 nm or less.

[0018] The silicon nitride film 4 on the substrate side is provided on one surface 2a of the substrate 2. The silicon nitride film 4 on the substrate side is obtained, for example, by modifying a polysilazane compound film with vacuum ultraviolet light in an N2 atmosphere. Specifically, it is obtained by a method including applying a perhydropolysilazane (PHPS) solution onto the substrate 2 by, for example, spin coating, removing the solvent by, for example, pre-baking, and then irradiating the PHPS film with vacuum ultraviolet light at a wavelength of 172 nm in an N2 atmosphere at room temperature. SiN x An example of the reaction for producing a (x>0) film is shown in Chemical Formula 1 below. As shown in Chemical Formula 1, Si-N bonds are formed to form SiN x As a result of this, H2 is released.

[0019] [ka]

[0020] Because the PHPS film is formed on the substrate 2 by coating, a flat surface can be obtained even if the substrate 2 has unevenness due to particles or the like. Therefore, the silicon nitride film 4 on the substrate side also serves as a planarizing film. Furthermore, forming the PHPS film by coating can reduce the manufacturing cost of the film. The silicon nitride film 4 obtained by the modification process can have a refractive index that varies in the thickness direction of the gas barrier film (e.g., the z-axis direction). Because vacuum ultraviolet light primarily modifies the surface layer of the film, the SiN conversion reaction occurs continuously from the surface layer toward the substrate side. Therefore, the silicon nitride film 4 has a gradation in which the silicon nitride concentration is higher on the surface side than on the substrate side. Therefore, the silicon nitride film 4 can have a characteristic in which the refractive index increases from the substrate side toward the surface side.

[0021] The silicon nitride film 5 on the surface side is provided on a surface parallel to the xy plane of the silicon nitride film 4. The silicon nitride film 5 on the surface side has a blocking ability against ultraviolet rays with a wavelength of 380 nm or less. The silicon nitride film 5 on the surface side preferably has a molar ratio of Si atoms to N atoms (Si / N) greater than 1. The Si-Si bond can enhance the absorption effect of ultraviolet rays with a wavelength of 380 nm or less. By increasing the molar ratio (Si / N) to greater than 1, it is possible to obtain a first layer 3 having high transmittance for visible light and high absorption ability for ultraviolet rays with a wavelength of 380 nm or less. Furthermore, since the stress of the silicon nitride film 5 can be reduced, the silicon nitride film 5 can be formed at a low temperature. It is more preferable that the molar ratio (Si / N) be 2 or greater. This further improves the ultraviolet blocking ability. The silicon nitride film 5 on the surface side is formed by, for example, chemical vapor deposition (CVD).

[0022] The gas barrier film 1 shown in FIG. 1 has excellent barrier properties against gases such as water vapor and oxygen. The gas barrier film 1 also has the ability to block ultraviolet light with a wavelength of 380 nm or less while being transparent to visible light. Furthermore, because the first layer 3 includes a plurality of silicon nitride films 4 and 5, sufficient barrier properties can be obtained even if the thickness of each of the silicon nitride films 4 and 5 is thin. As a result, defects such as cracks in the silicon nitride films 4 and 5 can be avoided.

[0023] While FIG. 1 illustrates an example in which the silicon nitride film 5 on the surface side has the ability to block ultraviolet rays with wavelengths of 380 nm or less, the silicon nitride film 4 on the substrate side may have the ability to block ultraviolet rays instead of the silicon nitride film 5 on the surface side. Alternatively, both the silicon nitride film 5 on the surface side and the silicon nitride film 4 on the substrate side may have the ability to block ultraviolet rays. In these cases, it is desirable that the molar ratio (Si / N) of the silicon nitride film 4 on the substrate side be greater than 1. A more preferable molar ratio (Si / N) is 2 or greater. Furthermore, while FIG. 1 illustrates an example in which the first layer 3 is directly laminated on one surface of the substrate 2, the present invention is not limited to this, and another layer, such as a planarizing layer, may be interposed between the substrate 2 and the first layer 3.

[0024] Next, the gas barrier film shown in Fig. 2 will be described. The gas barrier film 6 shown in Fig. 2 includes a substrate 2 and a first layer 3. Details of the substrate 2 are as described in Fig. 1.

[0025] The first layer 3 is provided on one surface of the substrate 2. In the case of FIG. 2, the first layer 3 is laminated on one surface 2a of the substrate 2. The first layer 3 has barrier properties against gases such as water vapor and oxygen. The first layer 3 also has blocking properties against ultraviolet rays with wavelengths of 380 nm or less. The first layer 3 essentially consists of, for example, a material film 7 serving as a planarization film and a silicon nitride film 8. At least one of the material film 7 and the silicon nitride film 8 has blocking properties against ultraviolet rays with wavelengths of 380 nm or less. The material film 7 and the silicon nitride film 8 each have two main surfaces (principal surfaces) that intersect with the thickness direction (z-axis direction). Each surface is parallel to the xy plane.

[0026] The material film 7 is provided on one surface 2a of the substrate 2. The material film 7 is a film whose matrix is ​​a material other than silicon nitride. However, since the material film 7 is in contact with the silicon nitride film 8, silicon nitride may be mixed in. The material film 7 can be obtained, for example, by applying a coating agent containing a material other than silicon nitride to one surface 2a of the substrate 2 and drying it. Examples of coating agents include a solution containing a material other than silicon nitride and a suspension containing a material other than silicon nitride. Forming the material film 7 by this coating method makes it easy to obtain a flat surface even if the substrate 2 has minute irregularities due to particles or the like. Examples of the material film 7 include a silicone compound film, a silicon oxide film modified with a silicone compound, a silicon oxide film modified with a polysilazane compound, an organic-inorganic hybrid film, and an organic film.

[0027] The silicon oxide film can also be obtained by, for example, modifying a polysilazane compound film with vacuum ultraviolet light in an O2 atmosphere. Specifically, it can be obtained by a method including applying a perhydropolysilazane (PHPS) solution onto the substrate 2 by, for example, spin coating, removing the solvent by, for example, pre-baking, and then irradiating the film with vacuum ultraviolet light (VUV) in an O2 atmosphere. SiO2 can be obtained by irradiating a PHPS film formed by applying and drying a PHPS solution with vacuum ultraviolet light at a wavelength of 172 nm in an O2 atmosphere at room temperature. x An example of the reaction for producing a (x>0) film is shown in Chemical Formula 2 below. As shown in Chemical Formula 2, Si-O bonds are formed to form SiO x As a result of the generation of NH3, NH3 is released. Instead of the modification treatment using vacuum ultraviolet light, the polysilazane compound film can also be modified to obtain a silicon oxide film by heating it in an O2 atmosphere.

[0028] [ka]

[0029] The material film 7 may or may not have the ability to block ultraviolet rays with wavelengths of 380 nm or less. An example of a material film 7 that has the ability to block ultraviolet rays with wavelengths of 380 nm or less is a film containing a resin having a group capable of absorbing ultraviolet rays with wavelengths of 380 nm or less. Examples of resins having a group capable of absorbing ultraviolet rays include acrylic resins having at least one skeleton or group selected from the group consisting of a triazine skeleton, a benzophenone skeleton, a benzotriazole skeleton, a salicylate skeleton, and a cyano group, and silicone resins having at least one skeleton or group selected from the group consisting of a triazine skeleton, a benzophenone skeleton, a benzotriazole skeleton, a salicylate skeleton, and a cyano group. The material film 7 may also contain a UV-absorbing silicone rubber material for LIMS (registered trademark) manufactured by Shin-Etsu Silicone (registered trademark) manufactured by Shin-Etsu Chemical Co., Ltd., or an ultraviolet-cutting coating agent (Hals Hybrid (registered trademark) UV-G) manufactured by Nippon Shokubai Co., Ltd. The material film 7 may be formed from one or more materials selected from the above types.

[0030] The silicon nitride film 8 is provided on a surface of the material film 7 parallel to the xy plane. The silicon nitride film 8 is not particularly limited as long as it contains silicon nitride. For example, it can be obtained by modifying a polysilazane compound film with vacuum ultraviolet light in an N2 atmosphere. Details of the modification process are as described for the gas barrier film with reference to FIG. 1. The silicon nitride film 8 can be similar to the silicon nitride film 4. The silicon nitride film 8 may also be formed by chemical vapor deposition (CVD). The silicon nitride film 8 may or may not have the ability to block ultraviolet light with a wavelength of 380 nm or less. To block ultraviolet light with a wavelength of 380 nm or less, the silicon nitride film 8 preferably has a molar ratio of Si atoms to N atoms (Si / N) greater than 1. By increasing the molar ratio (Si / N) to greater than 1, a first layer 3 having high visible light transmittance and high absorption of ultraviolet light with a wavelength of 380 nm or less can be obtained. Furthermore, since the stress of the silicon nitride film 8 can be reduced, the silicon nitride film 8 can be formed by CVD at a low temperature. It is more preferable that the molar ratio (Si / N) is 2 or more, which can further improve the ultraviolet ray blocking performance.

[0031] In the gas barrier film 6, at least one of the material film 7 and the silicon nitride film 8 may have the ability to block ultraviolet rays with wavelengths of 380 nm or less. For example, if one of the material film 7 or the silicon nitride film 8 has the ability to block ultraviolet rays with wavelengths of 380 nm or less, the other may not have the ability to block ultraviolet rays with wavelengths of 380 nm or less. Both the material film 7 and the silicon nitride film 8 may have the ability to block ultraviolet rays with wavelengths of 380 nm or less. In this case, the ability of the first layer 3 to block ultraviolet rays with wavelengths of 380 nm or less can be further improved.

[0032] 2 has excellent barrier properties against gases such as water vapor and oxygen. In addition, the gas barrier film 6 has visible light transmittance and can also block ultraviolet light with a wavelength of 380 nm or less.

[0033] In addition, in Figure 2, an example is described in which the first layer 3 is directly laminated on one side of the base material 2, but this is not limited to this, and another layer such as an adhesive layer may be interposed between the base material 2 and the first layer 3.

[0034] Next, the gas barrier film shown in Fig. 3 will be described. The gas barrier film 9 shown in Fig. 3 includes a substrate 2, a first layer 3, and a second layer 10. Details of the substrate 2 are as described in Fig. 1.

[0035] The first layer 3 is provided on one surface of the substrate 2. In the case of FIG. 3, the first layer 3 is laminated on one surface 2a of the substrate 2. The first layer 3 has a barrier property against gases such as water vapor and oxygen. The first layer 3 essentially consists of, for example, a material film 7 serving as a planarizing film and a silicon nitride film 8. Details of the material film 7 and the silicon nitride film 8 are as explained in FIG. 2. Note that the material film 7 and the silicon nitride film 8 do not necessarily have a blocking property against ultraviolet light with a wavelength of 380 nm or less.

[0036] The second layer 10 is provided on the other surface 2b of the substrate 2. In the case of FIG. 3, the second layer 10 is laminated on the other surface 2b of the substrate 2. The second layer 10 may be optically transparent. The second layer 10 has the ability to block ultraviolet light with a wavelength of 380 nm or less. The second layer 10 can function as a planarizing layer or film. The second layer 10 can also reduce the difference between the stress applied to one surface 2a of the substrate 2 and the stress applied to the other surface 2b of the substrate 2. Therefore, the second layer 10 can prevent the substrate 2 from warping due to the stress difference. The second layer 10 preferably has a matrix made of a material other than silicon nitride. Examples of materials for forming the second layer 10 include resins having groups capable of absorbing ultraviolet light with a wavelength of 380 nm or less. Examples of resins having groups capable of absorbing ultraviolet light include those described for the material film 7. The second layer 10 can be formed from one or more materials selected from the types described above.

[0037] The gas barrier film 9 shown in FIG. 3 has excellent barrier properties against gases such as water vapor and oxygen. The gas barrier film 9 is also capable of blocking ultraviolet light with a wavelength of 380 nm or less while being transparent to visible light. The gas barrier film 9 has a first layer 3 provided on one side of the substrate 2 and a second layer 10 provided on the other side of the substrate 2. This reduces the difference between the stress applied to one side of the substrate 2 and the stress applied to the other side, thereby suppressing warping of the substrate 2.

[0038] In addition, in Figure 3, an example is described in which the first layer 3 and the second layer 10 are directly laminated on both sides of the base material 2, respectively, but this is not limited to this, and another layer such as an adhesive layer may be interposed between the base material 2 and the first layer 3 or the second layer 10.

[0039] The use of the gas barrier film of the first embodiment is not particularly limited, but is preferably used in applications requiring gas barrier properties against water vapor, oxygen, etc. The gas barrier film of the first embodiment can be used, for example, in photoelectric conversion devices. Examples of photoelectric conversion devices include solar cell devices and organic electroluminescence (organic EL).

[0040] The gas barrier film of the first embodiment described above includes a substrate and a first layer provided on at least one side of the substrate. The gas barrier film of the first embodiment also has the ability to block ultraviolet light with a wavelength of 380 nm or less. Therefore, the gas barrier film of the first embodiment has excellent gas barrier properties and excellent ability to block ultraviolet light with a wavelength of 380 nm or less. (Second embodiment) According to the second embodiment, a photoelectric conversion device is provided. The photoelectric conversion device includes a photoelectric conversion element and the gas barrier film of the first embodiment. The photoelectric conversion device can be, for example, a solar cell device, an organic electroluminescence (organic EL), or the like.

[0041] An example in which the photoelectric conversion device of the embodiment is applied to a solar cell device will be described with reference to Figs. 4 to 6. In each figure, the thickness direction of the solar cell device is parallel to the z-axis direction. The surface direction of the solar cell device is parallel to a plane defined by the x-axis and y-axis directions. The x-axis, y-axis, and z-axis directions intersect perpendicularly with each other. In each figure, components that are common to multiple figures are designated by the same reference numerals, and their description will be omitted.

[0042] The solar cell device 100 shown in FIG. 4 includes the gas barrier film 1 of the first embodiment and a solar cell element 11. The details of the gas barrier film 1 are as described in the first embodiment. The solar cell element 11 includes a transparent electrode 12 as a first electrode, a hole transport layer 13, a photoelectric conversion layer 14, an electron transport layer 15, a cathode 16 as a second electrode, an adhesive layer 17, and a backsheet 18. The transparent electrode 12, the hole transport layer 13, the photoelectric conversion layer 14, the electron transport layer 15, and the cathode 16 each have two main surfaces (principal surfaces) that intersect with the thickness direction (z-axis direction). Each surface is parallel to the xy plane. The transparent electrode 12 is provided on a surface 5a of the silicon nitride film 5 on the surface side of the gas barrier film 1, which is parallel to the xy plane. One surface of the transparent electrode 12 parallel to the xy plane is in contact with the surface 5a. A hole transport layer 13, a photoelectric conversion layer 14, an electron transport layer 15, and a cathode 16 are provided in this order on the other surface of the transparent electrode 12 parallel to the xy plane. A back sheet 18 is fixed to one surface of the cathode 16 parallel to the xy plane by an adhesive layer 17. Light such as sunlight or illumination is irradiated onto the other surface 2b of the substrate 2 of the gas barrier film 1 from a first direction 19, for example.

[0043] Examples of the transparent electrode 12 as the first electrode include films made of materials that are optically transparent and conductive, such as indium tin oxide (ITO), zinc oxide (ZnO), tin dioxide (SnO2), and fluorine-doped tin oxide (FTO).

[0044] The hole transport layer 13 has functions such as blocking electrons generated in the photoelectric conversion layer 14 and transporting holes selectively and efficiently to the cathode 16 .

[0045] A perovskite layer is an example of the photoelectric conversion layer 14. An example of a perovskite compound is methylammonium lead iodide (CH3NH3PbI3).

[0046] The electron transport layer 15 has functions such as blocking holes generated in the photoelectric conversion layer 14 and transporting electrons selectively and efficiently to the transparent electrode 12 .

[0047] The cathode 16 as the second electrode is made of a material that is electrically conductive and, in some cases, optically transparent. The cathode 16 may be, for example, a layer containing Ti and / or Al. When light is irradiated onto the other surface 2b of the substrate 2 of the gas barrier film 1 from the first direction 19, for example, in the solar cell device 100 having the above structure, and the irradiated light is absorbed by the photoelectric conversion layer 14, electrons and their paired holes are generated. Of the generated electrons and holes, for example, the electrons are collected by the cathode 16 via the electron transport layer 15. The holes are collected by the transparent electrode 12 via the hole transport layer 13. In this way, a photoelectric conversion reaction occurs.

[0048] The gas barrier film 1 can block ultraviolet rays with wavelengths of 380 nm or less without interfering with the irradiation of visible light onto the solar cell element 11, thereby suppressing ultraviolet degradation of the photoelectric conversion layer 14. As a result, the light durability of the solar cell device 100 can be improved.

[0049] Next, a solar cell device 101 shown in FIG. 5 will be described. The solar cell device 101 includes the gas barrier film 6 of the first embodiment and a solar cell element 11. Details of the gas barrier film 6 are as described in the first embodiment. Details of the solar cell element 11 are the same as those of the solar cell device 100 described with reference to FIG. 4. A transparent electrode 12 of the solar cell element 11 is laminated on a surface 8a of the silicon nitride film 8 of the gas barrier film 6 that is parallel to the xy plane. Light such as sunlight or illumination light is irradiated onto the other surface 2b of the base material 2 of the gas barrier film 6 from, for example, a first direction 19. When the solar cell device 101 having the above structure is irradiated with light from the first direction 19, for example, onto the other surface 2b of the base material 2 of the gas barrier film 6, the gas barrier film 6 can block ultraviolet rays with wavelengths of 380 nm or less without interfering with visible light being irradiated onto the solar cell element 11, thereby suppressing deterioration of the photoelectric conversion layer 14 due to ultraviolet rays. As a result, the light durability of the solar cell device 101 can be improved.

[0050] Next, a solar cell device 102 shown in FIG. 6 will be described. The solar cell device 102 includes the gas barrier film 9 of the first embodiment and a solar cell element 11. Details of the gas barrier film 9 are as described in the first embodiment. Details of the solar cell element 11 are the same as those of the solar cell device 100 described with reference to FIG. 4. A transparent electrode 12 of the solar cell element 11 is laminated on a surface 8a of the silicon nitride film 8 of the gas barrier film 9 that is parallel to the xy plane. Light such as sunlight or illumination light is irradiated onto the second layer 10 side of the gas barrier film 9 from, for example, a first direction 19. When light is irradiated onto the solar cell device 102 having the above structure, for example, from the first direction 19 toward the second layer 10 of the gas barrier film 9, the gas barrier film 9 can block ultraviolet rays with wavelengths of 380 nm or less without interfering with the irradiation of visible light onto the solar cell element 11, thereby suppressing deterioration of the photoelectric conversion layer 14 due to ultraviolet rays. As a result, the light durability of the solar cell device 102 can be improved. Furthermore, the second layer 10 of the gas barrier film 9 can suppress warping of the base material 2, thereby preventing deformation such as warping of the solar cell device 102.

[0051] In the above example, the first electrode (transparent electrode 12) is the anode and the second electrode is the cathode 16, but the arrangement of these electrodes may be reversed. That is, the first electrode (transparent electrode 12) may be the cathode and the second electrode may be the anode. In this case, the positions of the hole transport layer 13 and the electron transport layer 15 are also reversed.

[0052] Although not shown, a gas barrier film may be provided on the second electrode side in addition to the first electrode side. The back sheet 18 may be omitted, and instead a gas barrier film may be placed on the second electrode. If a light-transmitting electrode, i.e., a transparent electrode, is used as the second electrode, light can be taken in from the second electrode side as well. This makes it possible to receive light from both sides of the solar cell device.

[0053] As described above, the photoelectric conversion device of the second embodiment includes the gas barrier film of the first embodiment, and therefore can block ultraviolet rays with wavelengths of 380 nm or less without interfering with the irradiation of visible light onto the photoelectric conversion element, thereby suppressing deterioration of the photoelectric conversion element due to ultraviolet rays, thereby improving the light durability of the photoelectric conversion device. [Example]

[0054] Examples of gas barrier films are described below: Gas barrier film 1 described with reference to Fig. 1 was produced, and the light transmittance was measured.

[0055] A solution of PHPS (perhydropolysilazane) was applied by spin coating to a film thickness of 200 nm on a PET substrate as the substrate 2. After removing the solvent contained in the obtained film by pre-baking, the film was irradiated with vacuum ultraviolet light of 172 nm wavelength at 12 J / cm under a N2 atmosphere. 2 By irradiating the coating type SiN x The (x>0) film was formed as the silicon nitride film 4 on the substrate side. Next, coating type SiN x The upper layer of the film is SiN by plasma CVD. x The film (silicon nitride film 5 on the surface side) was formed to a thickness of 1 μm. The gas ratio of SiH4 / NH3 / N2 was set to 2 / 1 / 33, and the film was formed at a pressure of 100 Pa, a power of 300 W, and a temperature of 60°C. SiN x The molar ratio of Si atoms to N atoms (Si / N) of the film was 1.38. The molar ratio (Si / N) can be adjusted by changing the composition ratio of the gas. The water vapor transmission rate (WVTR) of the obtained gas barrier film 1 was 10 -4 Unit (g / m 2 / 24h) or less. WVTR was evaluated using a gas and water vapor transmission rate measuring device (single chamber type (MAT), using the MA method) manufactured by MORESCO Corporation. The results indicate that the transmission rate of oxygen, which has a larger molecular size than water vapor, is also low. These findings confirm that the gas barrier film has barrier properties against water vapor and oxygen.

[0056] The resulting gas barrier film was irradiated with light of wavelengths from 200 nm to 800 nm, and the light transmittance was measured. The results are shown in Figure 7. In addition, a PET substrate alone was prepared as a comparison example, and the light transmittance was measured when the PET substrate alone was irradiated with light of wavelengths from 200 nm to 800 nm. The results are also shown in Figure 7.

[0057] The horizontal axis of Figure 7 is the wavelength of light (nm) and the vertical axis is light transmittance (%). The measurement results for the Example are shown by a solid line, and the measurement results for the Comparative Example are shown by a dotted line. As shown in Figure 7, the gas barrier film of the Example had a transmittance of 50% or less for ultraviolet light with a wavelength of 315-360 nm, and was able to reduce the transmission of ultraviolet light with a wavelength of 380 nm or less. In contrast, the Comparative Example, which consisted of a single PET substrate, had a transmittance of 60% or more for ultraviolet light with a wavelength of 315-360 nm.

[0058] A light durability test was conducted on the solar cell elements of the solar cell device of the embodiment by irradiating them with simulated sunlight through filters with different cutoff wavelengths. Specifically, a transparent electrode 12 made of an ITO film, a hole transport layer 13, a photoelectric conversion layer 14, an electron transport layer 15, and a cathode 16 made of a TiAl alloy layer were stacked in this order on a PET substrate. The photoelectric conversion layer 14 was a perovskite layer containing methylammonium lead iodide. A filter was installed on the opposite side of the PET substrate from the solar cell element side. Simulated sunlight was irradiated from the filter side, and the retention rate of the conversion efficiency after 485 hours of irradiation relative to the initial conversion efficiency was measured. The filter cutoff wavelength was changed to 370 nm and 380 nm. Test solar cells irradiated without a UV cutoff filter showed a 20-30% decrease in conversion efficiency from the initial conversion efficiency after 485 hours of irradiation. In contrast, for the test solar cell equipped with 370 nm and 380 nm UV cut filters, the decrease in conversion efficiency after 485 hours of light irradiation was within 10% of the initial conversion efficiency. From these results, it can be expected that the gas barrier film of the example can suppress the decrease in conversion efficiency of the solar cell device when irradiated with light, and improve the light durability of the solar cell device. The gas barrier film of at least one of these embodiments or examples includes a substrate and a first layer provided on at least one side of the substrate, and has blocking properties against ultraviolet rays with wavelengths of 380 nm or less. Therefore, the gas barrier film can have improved blocking properties against ultraviolet rays with wavelengths of 380 nm or less while maintaining gas barrier properties.

[0059] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the claims. [Explanation of symbols]

[0060] 1, 6, 9...gas barrier film, 2...substrate, 2a, 2b...surface (main surface), 3...first layer, 4...substrate-side silicon nitride film, 5...front-side silicon nitride film, 5a...surface (main surface), 7...material film, 8...silicon nitride film, 8a...surface (main surface), 10...second layer, 11...solar cell element, 12...transparent electrode, 13...hole transport layer, 14...photoelectric conversion layer, 15...electron transport layer, 16...cathode, 17...adhesive layer, 18...backsheet, 19...first direction, 100, 101, 102...solar cell device.

Claims

1. A substrate; a first layer provided on at least one surface of the substrate; A gas barrier film having blocking properties against ultraviolet rays with wavelengths of 380 nm or less.

2. 2. The gas barrier film according to claim 1, wherein the first layer is a gas barrier layer having a blocking ability against ultraviolet rays having a wavelength of 380 nm or less.

3. 3. The gas barrier film according to claim 2, wherein the gas barrier layer comprises at least one of a silicon nitride film having a blocking ability against ultraviolet rays having a wavelength of 380 nm or less, and a film (excluding a silicon nitride film) having a blocking ability against ultraviolet rays having a wavelength of 380 nm or less.

4. The gas barrier film according to claim 3 , wherein the silicon nitride film has a molar ratio of Si atoms to N atoms of greater than 1.

5. The gas barrier film according to claim 3 , wherein the silicon nitride film has a refractive index that varies in the thickness direction.

6. 4. The gas barrier film according to claim 3, wherein the film (excluding a silicon nitride film) having a shielding property against ultraviolet rays having a wavelength of 380 nm or less contains at least one of an acrylic resin having at least one skeleton selected from the group consisting of a triazine skeleton, a benzophenone skeleton, a benzotriazole skeleton, a salicylate skeleton, and a cyano group, or a silicone resin having at least one skeleton selected from the group consisting of a triazine skeleton, a benzophenone skeleton, a benzotriazole skeleton, a salicylate skeleton, and a cyano group.

7. the first layer is a gas barrier layer provided on one surface of the base material, The gas barrier film according to claim 1 , further comprising a second layer provided on the other surface of the substrate and having a blocking ability against ultraviolet rays having a wavelength of 380 nm or less.

8. 8. The gas barrier film according to claim 7, wherein the second layer comprises at least one of an acrylic resin having at least one skeleton selected from the group consisting of a triazine skeleton, a benzophenone skeleton, a benzotriazole skeleton, a salicylate skeleton, and a cyano group, and a silicone resin having at least one skeleton selected from the group consisting of a triazine skeleton, a benzophenone skeleton, a benzotriazole skeleton, a salicylate skeleton, and a cyano group.

9. a photoelectric conversion element; A photoelectric conversion device provided on the photoelectric conversion element, comprising the gas barrier film according to any one of claims 1 to 8.

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