Solar cell module

Abstract

To provide a solar cell module capable of suppressing the appearance of black or navy blue in the appearance of the solar cell module and suppressing a decrease in power generation efficiency.SOLUTION: A solar cell module 1 includes a deposition layer 102 arranged on a light receiving surface side of a solar cell SC and formed by metal deposition. The vapor deposition layer 102 has a function of making black or navy blue due to the solar cell SC or the like less visible while transmitting sunlight necessary for solar power generation. Therefore, by disposing vapor deposition layer 102 on the light receiving surface side of solar cell SC, it is possible to prevent black or navy blue from appearing on the appearance of solar cell module 1. As described above, it is possible to suppress the appearance of black or navy blue in the appearance of the solar cell module 1 and to suppress a decrease in power generation efficiency.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a solar cell module. [Background technology]

[0002] With the aim of achieving carbon neutrality and a decarbonized society by 2050, there is a need for the widespread adoption of ZEBs (Net Zero Energy Buildings), which can significantly reduce energy consumption in buildings. A ZEB is a building that aims to achieve a zero annual balance of primary energy consumption while realizing a comfortable indoor environment. Since people are active inside a building, it is impossible to completely reduce energy consumption to zero. However, by reducing energy consumption through energy conservation and generating the equivalent energy through energy generation, it is possible to achieve net energy consumption of zero.

[0003] Energy generation methods that do not use fossil fuels include, for example, solar power generation, wind power generation, biomass power generation, etc. As an energy generation method for buildings, solar power generation is suitable when taking into account installation location and costs.

[0004] The rooftop area of ​​buildings is taken up by outdoor units for air conditioning and other equipment, so in order to generate electricity, solar cell modules had to be installed on the walls as well as the roof. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-27266 Summary of the Invention [Problem to be solved by the invention]

[0006] As in the solar cell module shown in Cited Document 1, printed matter is sometimes combined with solar cells to impart a design to them. Instead of or in addition to such printed matter, there has been a demand for a method to prevent the black or dark blue color of solar cells from appearing on the exterior of a solar cell module. Furthermore, because solar cell modules generate electricity by receiving sunlight, if the sunlight is blocked excessively by the printed matter, there is a problem that power generation efficiency decreases.

[0007] The present invention is intended to solve the above-mentioned problems, and aims to provide a solar cell module that can prevent the appearance of black or dark blue color on the exterior of the solar cell module and can prevent a decrease in power generation efficiency. [Means for solving the problem]

[0008] [1] In one aspect, a solar cell module according to the present invention includes a solar cell; a vapor deposition layer formed by vapor deposition of a metal and disposed on the light-receiving surface side of the solar cell; and a decorated printed layer disposed on the outer layer side of the vapor deposition layer relative to the light-receiving surface, the printed layer having a first color pattern layer formed by a plurality of first color dots and a second color pattern layer disposed on the first color pattern layer and formed by a plurality of second color dots, each of the plurality of first color dots including a first color binder and a plurality of first color pigment chips dispersed within the first color binder, and each of the plurality of second color dots including a second color binder and a plurality of second color pigment chips dispersed within the second color binder. Either one of the plurality of first color pigment chips or the plurality of second color pigment chips is a first interference pigment of a plurality of colors that generates first interference light that is different from each other, and the other of the plurality of first color pigment chips or the plurality of second color pigment chips is a second interference pigment that generates a single-color second interference light that is different from the mixed color exhibited by the plurality of first interference pigments, and at least one of the first interference pigment and the second interference pigment includes a small particle size grade interference pigment having a particle size range of 5 μm to 25 μm and a large particle size grade interference pigment having a particle size range of 25 μm to 40 μm, and the small particle size grade interference pigment is arranged so as to fill the gaps between the large particle size grade interference pigments, and the plurality of first interference light and the second interference light are additively mixed.

[0009] The solar cell module described above includes a vapor deposition layer disposed on the light-receiving surface of the solar cell and formed by metal vapor deposition. The vapor deposition layer functions to obscure black or dark blue colors while allowing sunlight necessary for solar power generation to pass through. Therefore, by disposing the vapor deposition layer on the light-receiving surface of the solar cell, the appearance of black or dark blue colors in the solar cell module's exterior can be suppressed. As described above, the appearance of black or dark blue colors in the solar cell module's exterior can be suppressed and a decrease in power generation efficiency can be suppressed. The solar cell module further includes a decorative printed layer disposed on the outer layer side of the vapor deposition layer, facing the light-receiving surface. Therefore, the printed layer can impart a design to the solar cell module while suppressing the appearance of black or dark blue colors in the solar cell module's exterior. Furthermore, according to the inventors' research, it was found that when the particle size of the interference pigment contained in the printed layer is small, although color development is weak, the image can be prevented from appearing dark even when the printed layer is placed in front of a black screen. On the other hand, it has been found that if the particle size of the interference pigment contained in the pattern printed layer is large, the transparency of the printed layer increases, but the color development of the pattern can be improved. Therefore, the inventors have devised a printed layer that prevents the pattern from appearing too dark and has excellent color development by configuring the interference pigment to contain a small particle size grade interference pigment and a large particle size grade interference pigment, and arranging the small particle size grade interference pigment so that it fills the gaps between the large particle size grade interference pigments. Therefore, a printed layer with the above configuration can provide a pattern with excellent visibility and color development. Furthermore, by including a large particle size grade interference pigment in this printed layer, a decrease in the transparency of the printed layer is suppressed. Therefore, while achieving these effects, the printed layer can ensure the transparency of sunlight to the solar cell, thereby suppressing a decrease in the power generation efficiency of the solar cell module.

[0010] [2] The solar cell module of [1] above may have a film layer as the outermost layer on the light-receiving surface. In this case, the surface of the solar cell module can be protected by the film layer. Furthermore, by using the film layer as the outermost layer, the deposition surface can be protected. Furthermore, if a printed layer is provided, it has the advantage of protecting the printed layer, which is made of color pigment chips and has gaps and is therefore fragile.

[0011] [3] The solar cell module of [1] or [2] above may have a top coat layer as the outermost layer on the light-receiving surface. In this case, the surface of the solar cell module can be protected by the top coat layer. Furthermore, by using the top coat layer as the outermost layer, it becomes easier to adjust the gloss and it is less likely to be scratched during installation.

[0012] [4] The solar cell module of any one of [1] to [3] above may have a glass layer as the outermost layer on the light-receiving surface. In this case, the surface of the solar cell module can be protected by the glass layer. Furthermore, by using the glass layer as the outermost layer, it has the advantage of having excellent gas barrier properties, which delays deterioration.

[0013] [5] In the solar cell module of any one of [1] to [4] above, the total light transmittance of the vapor deposition layer may be 25% to 75%. In this case, the appearance of the solar cell module can be prevented from appearing black or dark blue. At the same time, excessive reduction in the power generation efficiency of the solar cell can be prevented.

[0014] [6] In the solar cell module of any one of [1] to [5] above, the large particle size grade interference pigment may have a particle size range of 25 μm to 60 μm. In this case, the color development of the pattern can be improved. Furthermore, by suppressing an unnecessary decrease in the transparency of the pattern-printed layer, when a display device is used, the visibility of the image on the display device can be improved.

[0015] [7] In the solar cell module of any one of [1] to [6] above, at least one of the small particle size grade interference pigment and the large particle size grade interference pigment may be an interference pigment containing titanium dioxide-coated mica. In this case, the wavelength of the interference light can be adjusted by adjusting the film thickness and transmittance of the titanium dioxide film. Furthermore, the luminance can be improved by increasing the smoothness of the mica surface. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a solar cell module that can prevent the appearance of black or dark blue color in the exterior of the solar cell module and can also prevent a decrease in power generation efficiency. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a cross-sectional view schematically showing a solar cell module according to a first embodiment. [Figure 2] FIG. 2 is a cross-sectional view that schematically shows a printed layer provided in the solar cell module shown in FIG. [Figure 3] FIG. 3 is a cross-sectional view schematically showing a picture printed layer included in the printed layer shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view schematically showing the print layer. [Figure 5] FIG. 5 is a cross-sectional view schematically showing a white pattern layer included in the print layer shown in FIG. [Figure 6] FIG. 6 is a cross-sectional view schematically showing the print layer. [Figure 7] FIG. 7 is a cross-sectional view schematically showing the print layer. [Figure 8] FIG. 8 is a cross-sectional view schematically showing a solar cell module according to the second embodiment. [Figure 9] FIG. 9 is a cross-sectional view schematically showing a solar cell module according to a third embodiment. [Figure 10] FIG. 10 is a cross-sectional view schematically showing a solar cell module according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0018] Specific examples of solar cell modules according to embodiments of the present invention will be described below with reference to the drawings. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims. In the following description, identical elements in the drawings will be designated by the same reference numerals, and duplicated descriptions will be omitted.

[0019] [First embodiment] Generally, the surfaces of the solar cells embedded in a solar cell module are only black or dark blue, and therefore attempts have been made to color the appearance of the solar cell module in various ways in order to improve its design. In this embodiment, a printed layer is applied to the surface of the solar cell module in a manner that makes it possible to improve the design of the appearance of the solar cell module while keeping the reduction in power generation of the solar cell very low.

[0020] Fig. 1 is a cross-sectional view schematically showing a solar cell module according to a first embodiment. As shown in Fig. 1, the solar cell module 1 includes a backing material 100, a sealing material layer 111, solar cells SC, and a surface layer 120. The surface layer 120 includes a film layer 101, a printing layer 2, a vapor deposition layer 102, and a transparent plate 103. Thin solar cells SC are placed on the backing material 100 with their light-receiving surfaces facing upward and embedded in the sealing material layer 111. The surface layer 120 is formed on the light-receiving surface side of the solar cells SC.

[0021] The solar cell SC may be a photoelectric conversion element formed in a thin plate shape with a thickness of about 0.2 mm from crystalline or amorphous silicon, thin film silicon, perovskite, chalcopyrite, III-V group silicon, CdTe, CIS, etc., which generates electricity by absorbing light with wavelengths mainly in the visible light range. The encapsulant layer 111 may be formed in a layer shape with a thickness of about 1 mm, surrounded by the solar cell SC, using a transparent material such as ethylene vinyl acetate (EVA), polyvinyl butyral (PVB), polyolefin resin, ionomer resin, or silicone resin, as shown in the figure.

[0022] The backing material 100 may be a layer, film, or plate made of PET (polyethylene terephthalate), polycarbonate resin, acrylic resin, glass, or metal (aluminum, etc.). The transparent plate 103 may be a plate-like member made of a transparent material such as polycarbonate resin, acrylic resin, or glass and having a thickness of about 3 mm. The transparent plate 103 and the sealing material layer 111, and the backing material 100 and the sealing material layer 111 may be bonded together by the adhesive strength of the sealing material layer 111.

[0023] The vapor-deposited layer 102 is disposed on the light-receiving surface side of the solar cell SC and is formed by vapor deposition of a metal. The vapor-deposited layer 102 is a layer that allows sunlight to pass through to the solar cell SC while concealing the black or dark blue color of the solar cell SC. The metal used for the vapor-deposited layer 102 may be aluminum, indium, tin, or other metals such as zinc, chromium, nickel, gold, or silver. Aluminum is advantageously low in cost. Indium is advantageously durable. Tin is advantageously non-conductive. The vapor-deposited layer 102 may be a film formed by vapor deposition in advance. Alternatively, the vapor-deposited layer 102 may be formed by sputtering or the like on another member (here, the printed layer 2) in the surface layer 120. The thickness of the vapor-deposited layer 102 may be 10 to 100 nm, preferably 15 to 60 nm, and more preferably 20 to 50 nm.

[0024] In this embodiment, the film layer 101 is disposed as the outermost layer for the solar cell SC. The film layer 101 is disposed on the outer main surface of the printed layer 2. The film layer 101 has the function of protecting other members of the surface layer 120 (here, the printed layer 2). Materials that may be used for the film layer 101 include, for example, acrylic resin, fluororesin, polypropylene resin, and polyester resin. The thickness of the film layer 101 may be 30 to 200 μm, preferably 40 to 180 μm, and more preferably 50 to 150 μm.

[0025] An adhesive layer may be provided between the vapor deposition layer 102 and the sealing material layer 111, instead of or in addition to the transparent plate 103. Such an adhesive layer is disposed between the main surface of the sealing material layer 111 and the vapor deposition layer 102 (or the transparent plate 103). Examples of materials that may be used for the adhesive layer include silicone resin, acrylic resin, and epoxy resin. The thickness of the adhesive layer may be 30 to 300 μm, preferably 40 to 200 μm, and more preferably 50 to 150 μm.

[0026] Here, the total light transmittance will be explained. The total light transmittance of the vapor-deposited layer 102 may be 25% to 75%. In particular, to prevent a decrease in the power generation efficiency of the solar cell module 1, the total light transmittance of the vapor-deposited layer 102 may be 25% or more. Furthermore, to prevent the solar cell module 1 from appearing black or dark blue, the total light transmittance of the vapor-deposited layer 102 may be 75% or less. The total light transmittance referred to here means a value measured using a spectrophotometer (for example, a UV-3600 spectrophotometer manufactured by Shimadzu Corporation).

[0027] As shown in FIG. 2, the print layer 2 is a sheet for expressing a pattern, and includes a light-transmitting substrate 4, a pattern print layer 5, and a translucent smoke print layer 30.

[0028] The light-transmitting substrate 4 is a substrate that is transparent to visible light. The light-transmitting substrate 4 is made of, for example, a transparent resin. Examples of transparent resins include PET, PMMA, polyethylene, polypropylene, nylon, and fluorine. The light-transmitting substrate 4 may be a glass substrate. The light-transmitting substrate 4 has a thickness of, for example, 25 μm to 250 μm. In the case of a glass substrate, the thickness is, for example, several mm to 10 mm. If necessary, a surface protection layer may be provided on the surface side of the light-transmitting substrate 4 (the side opposite to the picture printed layer 5).

[0029] The picture printed layer 5 is a layer that expresses the picture of the print layer 2. The picture printed layer 5 includes a first color pattern layer 10 provided on one surface 4a of the light-transmitting substrate 4, and a second color pattern layer 20 provided on the first color pattern layer 10.

[0030] The first color pattern layer 10 can be formed on the surface 4a by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 3, the first color pattern layer 10 is composed of a plurality of first color dots 11. Here, "dot" refers to a point that is an element constituting a printed image, and its shape is not limited to a circle but may be a rectangle, a polygon, or other shape. Each of the plurality of first color dots 11 contains a first color binder 12 and a plurality of first color pigment chips 13 dispersed within the first color binder 12. The content of the plurality of first color pigment chips 13 is, for example, in the range of 0.5 parts by weight to 20 parts by weight, where the first color binder 12 is 100 parts by weight.

[0031] Examples of the first color binder 12 include vinyl resins, acrylic resins, thermoplastic urethane resins, polyester resins, polycarbonate resins, and fluorine resins. The thickness of the first color pattern layer 10 is, for example, 1 μm to 10 μm. The first color pattern layer 10 may contain a curing agent. In this case, the heat resistance of the first color pattern layer 10 and the adhesion of the first color pattern layer 10 to the light-transmitting substrate 4 can be improved.

[0032] The multiple first color pigment chips 13 are multiple color first interference pigments 14a, 14b that generate different interference light from each other. Each of the first interference pigments 14a, 14b is composed of a thin flake (not shown) that is transparent to visible light and a metal oxide film (not shown) that covers the thin flake. Light incident on the first color pattern layer 10 from the translucent substrate 4 side is reflected by the surface of the metal oxide film, and light that passes through the metal oxide film and is reflected by the surface of the flake interferes with each other to generate interference light. Adjusting the thickness and refractive index of the metal oxide film allows generation of interference light with a desired wavelength.

[0033] Each of the first interference pigments 14a, 14b is, for example, titanium dioxide-coated mica. The flakes that make up the first interference pigments 14a, 14b may be made of materials other than mica, such as silica, alumina, glass, or polysilicate. The metal oxide films that make up the first interference pigments 14a, 14b may be made of materials other than titanium dioxide, such as zirconium oxide, zinc oxide, iron oxide, or tin oxide.

[0034] The first interference pigment 14a includes a plurality of first titanium dioxide-coated micas 15a of a small particle size grade having a particle size range of 5 μm to 25 μm and a second titanium dioxide-coated mica 15b of a large particle size grade having a particle size range of 25 μm to 40 μm. The first interference pigment 14b includes a plurality of first titanium dioxide-coated micas 16a of a small particle size grade having a particle size range of 5 μm to 25 μm and a plurality of second titanium dioxide-coated micas 16b of a large particle size grade having a particle size range of 25 μm to 40 μm. The first titanium dioxide-coated micas 15a, 16a have an average particle size (D50) of, for example, about 15 μm, and the second titanium dioxide-coated micas 15b, 16b have an average particle size (D50) of, for example, about 25 μm. As a result, the average particle size of the first titanium dioxide-coated mica 15a, 16a is smaller than the average particle size of the second titanium dioxide-coated mica 15b, 16b. The second titanium dioxide-coated mica 15b, 16b may have a particle size range of 25 μm to 60 μm. In this case, the average particle size (D50) of the second titanium dioxide-coated mica 15b, 16b is, for example, approximately 35 μm. As shown in FIG. 2, each of the multiple first titanium dioxide-coated mica 15a, 16a is arranged so as to fill the gaps between the multiple second titanium dioxide-coated mica 15b, 16b. Here, "particle size" refers to the longest diameter of the particle cross section.

[0035] When incident light L enters the first color pattern layer 10, the first interference pigments 14a and 14b generate first interference lights 17a and 17b, which are different from each other. That is, the wavelengths of the first interference lights 17a and 17b are different from each other. As a result, the first interference pigments 14a and 14b exhibit a mixed color. The first interference pigments 14a and 14b may be, for example, a red interference pigment (red pearl pigment) and a gold interference pigment (gold pearl pigment), respectively. In this case, the first interference lights 17a and 17b exhibit red and gold, respectively. The first interference pigments 14a and 14b may be interference pigments of other colors. The blending amounts of the first interference pigments 14a and 14b may be the same or different from each other.

[0036] The second color pattern layer 20 can be formed on the first color pattern layer 10 by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 3 , the second color pattern layer 20 is composed of a plurality of second color dots 21. Here, "dot" refers to a point that is an element constituting a printed image, and its shape is not limited to a circle but may be a rectangle, a polygon, or other shape. Each of the plurality of second color dots 21 contains a second color binder 22 and a plurality of second color pigment chips 23 dispersed within the second color binder 22. The content of the plurality of second color pigment chips 23 is, for example, in the range of 0.5 parts by weight to 20 parts by weight, where the second color binder 22 is 100 parts by weight.

[0037] Examples of the second color binder 22 include vinyl resins, acrylic resins, thermoplastic urethane resins, polyester resins, polycarbonate resins, and fluorine resins. The thickness of the second color pattern layer 20 is, for example, 1 μm to 10 μm. The second color pattern layer 20 may contain a curing agent. In this case, the heat resistance of the second color pattern layer 20 and the adhesion of the second color pattern layer 20 to the first color pattern layer 10 can be improved.

[0038] The multiple second color pigment chips 23 are second interference pigments 24 that generate monochromatic interference light different from the mixed color of the first interference pigments 14a and 14b. The second interference pigments 24 are composed of flakes (not shown) that are transparent to visible light and a metal oxide film (not shown) that covers the flakes. Light incident on the second color pattern layer 20 from the translucent substrate 4 side is reflected by the surface of the metal oxide film, and light that passes through the metal oxide film and is reflected by the surface of the flakes interferes with each other to generate interference light. Adjusting the thickness and refractive index of the metal oxide film allows for the generation of interference light with a desired wavelength.

[0039] The second interference pigment 24 is, for example, titanium dioxide-coated mica. The flakes constituting the second interference pigment 24 may be made of materials other than mica, such as silica, alumina, glass, or polysilicate. The metal oxide film constituting the second interference pigment 24 may be made of materials other than titanium dioxide, such as zirconium oxide, zinc oxide, iron oxide, or tin oxide.

[0040] The second interference pigment 24 includes a plurality of first titanium dioxide-coated micas 25a of a small particle size grade including a particle size range of 5 μm to 25 μm and a second titanium dioxide-coated mica 25b of a large particle size grade including a particle size range of 25 μm to 40 μm. The first titanium dioxide-coated micas 25a have an average particle size (D50) of, for example, about 15 μm, and the second titanium dioxide-coated micas 25b have an average particle size (D50) of, for example, about 25 μm. Thus, the average particle size of the first titanium dioxide-coated micas 25a is smaller than the average particle size of the second titanium dioxide-coated micas 25b. The second titanium dioxide-coated micas 25b may have a particle size range of 25 μm to 60 μm. In this case, the average particle size (D50) of the second titanium dioxide-coated micas 25b is, for example, about 35 μm. The plurality of first titanium dioxide-coated mica particles 25a are arranged so as to fill the gaps between the plurality of second titanium dioxide-coated mica particles 25b. Here, the "particle size" means the longest diameter of the particle cross section.

[0041] When incident light L enters the second color pattern layer 20, the second interference pigment 24 generates a single-color second interference light 26. As a result, the second interference pigment 24 exhibits a single color. The second interference pigment 24 may be any interference pigment that generates a single-color second interference light 26 different from the mixed color exhibited by the first interference pigments 14a and 14b, and may be, for example, a green interference pigment (green pearl pigment). In this case, the second interference light 26 exhibits green. The second interference pigment 24 may be an interference pigment of a color other than green.

[0042] The transparent smoke printed layer 30 is a layer for attenuating light transmitted through the printed layer 2. The transparent smoke printed layer 30 is provided on the outermost surface of the picture printed layer 5, opposite the light-transmitting substrate 4. In the first embodiment, the transparent smoke printed layer 30 is provided on the second color pattern layer 20, as shown in FIG. 2. The transparent smoke printed layer 30 can be provided on the second color pattern layer 20 by, for example, screen printing, inkjet printing, gravure printing, or offset printing using ink in which a small amount of carbon black is dispersed in a resin binder such as a vinyl, acrylic, urethane, or polyester binder. The thickness of the transparent smoke printed layer 30 is, for example, 1 μm to 10 μm.

[0043] In the printing layer 2, the first interference light 17a, 17b generated by the first interference pigments 14a, 14b and the second interference light 26 generated by the second interference pigment 24 are additively mixed to form a picture.

[0044] The total light transmittance of the printed layer 2 is, for example, 30% to 70%. The total light transmittance here refers to a value measured using a spectrophotometer (for example, spectrophotometer UV-2100 manufactured by Shimadzu Corporation).

[0045] Next, the functions and effects of the solar cell module 1 according to this embodiment will be described.

[0046] The solar cell module 1 according to this embodiment is provided with a vapor deposition layer 102 formed by metal vapor deposition on the light-receiving surface side of the solar cells SC. The vapor deposition layer 102 has the function of making the black or dark blue color of the solar cells SC less visible while allowing sunlight necessary for solar power generation to pass through. Therefore, by disposing the vapor deposition layer 102 on the light-receiving surface side of the solar cells SC, it is possible to prevent the appearance of black or dark blue on the exterior of the solar cell module 1. As a result, it is possible to prevent the appearance of black or dark blue on the exterior of the solar cell module 1 and also to prevent a decrease in power generation efficiency.

[0047] The solar cell module 1 further includes a decorated printed layer 2 that is disposed on the outer layer side of the vapor deposition layer 102 relative to the light-receiving surface. Therefore, the printed layer 2 can impart a design to the solar cell module 1 while suppressing the appearance of black or dark blue in the appearance of the solar cell module 1.

[0048] Furthermore, in the printing layer 2, the first color pattern layer 10 contains the first interference pigments 14a and 14b, and the second color pattern layer 20 contains the second interference pigment 24, making it possible to achieve a three-dimensional pattern even with a small number of printing layers. Furthermore, in the printing layer 2, the first color pattern layer 10 is the only pattern layer of the first color pattern layer 10 and the second color pattern layer 20 that contains interference pigments that generate different interference light from each other, simplifying color matching and registration work during printing. Therefore, the printing layer 2 makes it possible to achieve a three-dimensional pattern even with a small number of printing layers, and also simplifies color matching and registration work during printing. Furthermore, while achieving these effects, the printing layer 2 ensures sunlight transmission to the solar cell SC, thereby suppressing a decrease in the power generation efficiency of the solar cell module 1.

[0049] In the printing layer 2, each of the plurality of first titanium dioxide-coated micas 15a, 16a having a small particle size grade in the particle size range of 5 μm to 25 μm is arranged in the first color pattern layer 10 so as to fill the gaps between the plurality of second titanium dioxide-coated micas 15b, 16b having a large particle size grade in the particle size range of 25 μm to 40 μm. In the printing layer 2, each of the plurality of first titanium dioxide-coated micas 25a having a small particle size grade in the particle size range of 5 μm to 25 μm is arranged in the second color pattern layer 20 so as to fill the gaps between the plurality of second titanium dioxide-coated micas 25b having a large particle size grade in the particle size range of 25 μm to 40 μm. Therefore, the printing layer 2 can provide a pattern with excellent visibility and color development. Furthermore, in the printed layer 2, the first color pattern layer 10 contains large particle size grade second titanium dioxide-coated mica 15b, 16b, and the second color pattern layer 20 contains large particle size grade second titanium dioxide-coated mica 25b, thereby suppressing a decrease in the transparency of the picture printed layer 5. Therefore, while achieving these effects, the printed layer 2 can also ensure transparency of the solar cell to sunlight, thereby suppressing a decrease in the power generation efficiency of the solar cell module 1.

[0050] In the first embodiment, the large particle size grade second titanium dioxide-coated mica 15b, 16b, 25b may have a particle size range of 25 μm to 60 μm. In this case, the color development of the pattern is more excellent. Furthermore, by suppressing an unnecessary decrease in the transparency of the pattern-printed layer 5, when a display device is used, the visibility of the image on the display device can be improved.

[0051] In the first embodiment, the first interference pigments 14a, 14b and the second interference pigment 24 are interference pigments containing titanium dioxide-coated mica. Therefore, by adjusting the film thickness and transmittance of the titanium dioxide film, the wavelength of the interference light can be adjusted. Furthermore, by increasing the smoothness of the mica surface, the perceived brightness can be improved.

[0052] The printed layer 2 of the solar cell module 1 includes a transparent smoke printed layer 30 provided on the second color pattern layer 20. This provides better color development between the first color pattern layer 10 and the second color pattern layer 20. Furthermore, because the transparent smoke printed layer 30 is transparent, a decrease in the power generation efficiency of the solar cell module 1 is effectively suppressed.

[0053] The content of the plurality of first-color pigment chips 13 is within a range of 0.5 parts by weight to 20 parts by weight, where the first-color binder 12 is taken as 100 parts by weight, and the content of the plurality of second-color pigment chips 23 is within a range of 0.5 parts by weight to 20 parts by weight, where the second-color binder is taken as 100 parts by weight. Because the content of the plurality of first-color pigment chips 13 is within a range of 0.5 parts by weight or more, the design of the first-color pattern layer 10 is well expressed. Because the content of the plurality of first-color pigment chips 13 is within a range of 20 parts by weight or less, a decrease in the film-forming properties and transparency of the first-color pattern layer 10 can be suppressed. Similarly, because the content of the plurality of second-color pigment chips 23 is within a range of 0.5 parts by weight to 20 parts by weight, where the second-color binder 22 is taken as 100 parts by weight, the design of the second-color pattern layer 20 is well expressed, and a decrease in the film-forming properties and transparency of the second-color pattern layer 20 can be suppressed.

[0054] The solar cell module 1 may have a film layer 101 as the outermost layer on the light-receiving surface. In this case, the surface of the solar cell module 1 can be protected by the film layer 101. Furthermore, by using the film layer 101 as the outermost layer, the deposition surface can be protected. Note that when the solar cell module 1 has a printing layer 2 (described later), it has the advantage of protecting the printing layer 2, which is made of color pigment chips and has gaps and is therefore brittle.

[0055] In the solar cell module 1, the total light transmittance of the vapor deposition layer 102 may be 25% to 75%. In this case, it is possible to prevent the appearance of black or dark blue in the solar cell module 1. On the other hand, it is possible to prevent the power generation efficiency of the solar cells SC from decreasing excessively.

[0056] Another printed layer 2A will be described with reference to Figs. 4 and 5. Fig. 4 is a cross-sectional view schematically showing the printed layer 2A. Fig. 5 is a cross-sectional view schematically showing the white pattern layer provided in the printed layer 2A shown in Fig. 4. The printed layer 2A includes a light-transmitting substrate 4 and a picture printed layer 5. The printed layer 2A further includes a white pattern layer 40 provided on the second color pattern layer 20.

[0057] The white pattern layer 40 can be formed on the second color pattern layer 20 by, for example, screen printing, inkjet printing, gravure printing, or offset printing. As shown in FIG. 5 , the white pattern layer 40 is composed of a plurality of silver dots 41. Here, "dot" refers to a point that is an element constituting a printed image, and its shape is not limited to a circle, but may be a rectangle, a polygon, or other shape. Each of the plurality of silver dots 41 contains a silver binder 42 and a plurality of silver pigment chips 43 dispersed within the silver binder 42. The content of the plurality of silver pigment chips 43 is, for example, in the range of 0.5 parts by weight to 20 parts by weight, where the silver binder 42 is 100 parts by weight.

[0058] Examples of the silver binder 42 include vinyl resins, acrylic resins, thermoplastic urethane resins, polyester resins, and polycarbonate resins. The thickness of the white pattern layer 40 is, for example, 1 μm to 10 μm. The white pattern layer 40 may contain a curing agent. In this case, the heat resistance of the white pattern layer 40 and the adhesion of the white pattern layer 40 to the second color pattern layer 20 can be improved.

[0059] The configuration of the printed layer 2A described above also achieves the same effects as the previously described printed layer 2. Furthermore, the white pattern layer 40 is provided on the second color pattern layer 20 and is composed of a plurality of silver dots 41, and each of the plurality of silver dots 41 contains a silver binder 42 and a plurality of silver pigment chips 43 dispersed within the silver binder 42. This allows the color development of the first color pattern layer 10 and the second color pattern layer 20 to be excellent, and the picture printed layer 5 to have a pattern that gives a whitish impression.

[0060] Another printing layer 2B will be described with reference to FIG. 6. FIG. 6 is a cross-sectional view showing a schematic view of the printing layer 2B. The printing layer 2B comprises a light-transmitting substrate 4 and a picture printing layer 5. In other words, the printing layer 2B does not comprise a translucent smoke printing layer 30 or a white pattern layer 40. Even with the configuration of the printing layer 2B described above, the same effects as those of the printing layer 2 can be achieved.

[0061] Another printed layer 2C will be described with reference to FIG. 7. FIG. 7 is a cross-sectional view showing a schematic view of the printed layer 2C. The printed layer 2C comprises a light-transmitting substrate 4, a picture printed layer 5, a white pattern layer 40, and a transparent smoke printed layer 30. The white pattern layer 40 is provided on the second color pattern layer 20, and the transparent smoke printed layer 30 is provided on the white pattern layer 40. The configuration of the printed layer 2C described above also achieves the same effects as the other printed layers.

[0062] The solar cell module according to the present invention is not limited to the above-described embodiments, and various other modifications are possible. For example, the second color pattern layer may include first interference pigments of multiple colors that generate different first interference lights, and the first color pattern layer may include a second interference pigment that generates a single-color second interference light that is different from the mixed color exhibited by the multiple first interference pigments. Furthermore, in each of the above embodiments, the first color pigment chips are first interference pigments of two colors, but the first color pigment chips may be first interference pigments of three or more colors.

[0063] The print layer may also be formed using a pigment, such as an inorganic pigment such as titanium oxide, zinc oxide, carbon black, iron / composite oxide, iron oxide, or ultramarine, or an organic pigment such as isoindolinone, disazo, polyazo, diketopyrrolopyrrole, quinacridone, or phthalocyanine.

[0064] [Second embodiment] A solar cell module 1 according to the second embodiment will be described below with reference to Fig. 8. In the description of the second embodiment, descriptions that overlap with the first embodiment will be omitted, and only differences from the first embodiment will be described. In other words, the descriptions of the first embodiment may be used appropriately in the second embodiment to the extent technically possible.

[0065] 8 is a cross-sectional view schematically illustrating a solar cell module 1 according to a second embodiment. As shown in FIG. 8, the solar cell module 1 according to the second embodiment includes, in addition to the solar cell module 1 according to the first embodiment, a film layer 101 between the vapor deposition layer 102 and the printed layer 2, and a transparent plate 103 between the printed layer 2 and the outermost film layer 101. The film layer 101 and the transparent plate 103 may have the same configuration as the film layer 101 and the transparent plate 103 according to the first embodiment. An adhesive layer may be applied instead of or in addition to the transparent plate 103.

[0066] According to this configuration, the film layer 101 is interposed between the vapor-deposited layer 102 and the printed layer 2. The printed layer 2 is protected by being sandwiched between the pair of film layers 101. In this case, compared to the structure in Fig. 9 described below, there is an advantage that the vapor-deposited layer 102 is protected from the solvent contained in the ink when the printed layer 2 is formed.

[0067] [Third embodiment] A solar cell module 1 according to the third embodiment will be described below with reference to Fig. 9. In the description of the third embodiment, descriptions that overlap with the first and second embodiments will be omitted, and only differences from the first and second embodiments will be described. In other words, to the extent technically possible, the descriptions of the first and second embodiments may be used appropriately in the third embodiment.

[0068] Fig. 9 is a cross-sectional view schematically showing a solar cell module 1 according to the third embodiment. As shown in Fig. 9, the solar cell module 1 according to the third embodiment differs from the solar cell module 1 according to the third embodiment in that the stacking order of the deposition layer 102 and the film layer 101 is reversed. As a result, the printing layer 2 and the deposition layer 102 are arranged adjacent to each other.

[0069] This configuration results in an interposed configuration in which the vapor-deposited layer 102 and the printed layer 2 are in contact with each other. The printed layer 2 and the vapor-deposited layer 102 are protected by being sandwiched between a pair of film layers 101. This configuration has the advantage over the structure shown in FIG. 8 described above that the vapor-deposited layer 102 and the printed layer 2 are protected from the solvent contained in the adhesive when the adhesive layer is formed.

[0070] [Fourth embodiment] A solar cell module 1 according to a tenth embodiment will be described below with reference to Fig. 10. In the description of the fourth embodiment, descriptions that overlap with the first to third embodiments will be omitted, and only differences from the first to third embodiments will be described. In other words, the descriptions of the first embodiment may be used appropriately in the fourth embodiment to the extent technically possible.

[0071] Fig. 10 is a cross-sectional view schematically showing the solar cell module 1 according to the fourth embodiment. As shown in Fig. 10, the solar cell module 1 according to the fourth embodiment includes a protective layer 104A on the outer side of the film layer 101.

[0072] A top coat layer 104A may be employed as the protective layer 104. The top coat layer 104A may be, for example, the same as that applied to the painted surface of a vehicle or the like. The thickness of the top coat layer 104A may be 5 to 50 μm, preferably 10 to 40 μm, and more preferably 15 to 30 μm. The material for the top coat layer 104A may be an active energy ray-curable coating composition that is cured by ultraviolet irradiation, electron beams, or the like, or a heat-curable coating composition.

[0073] In this way, the solar cell module 1 may be provided with the top coat layer 104A as the outermost layer on the light-receiving surface. In this case, the surface of the solar cell module 1 can be protected by the top coat layer 104A. Furthermore, by using the top coat layer 104A as the outermost layer, it is possible to obtain the advantages of facilitating gloss adjustment and reducing scratch resistance during installation. Another advantage is that the film layer 101 can be protected from ultraviolet rays.

[0074] Furthermore, a glass layer 104B may be employed as the protective layer 104. For example, types of glass such as soda-lime glass and aluminoborosilicate glass are employed as the glass layer 104B, and the thickness of the glass layer 104B may be 2.0 to 5.0 mm, preferably 2.5 to 4.0 mm, and more preferably 2.5 to 3.0 mm.

[0075] The solar cell module 1 may include a glass layer 104B as the outermost layer on the light-receiving surface. In this case, the surface of the solar cell module 1 can be protected by the glass layer 104B. Furthermore, by using the glass layer 104B as the outermost layer, it is possible to obtain the advantage of retarding deterioration due to its excellent gas barrier properties. It is also possible to obtain the advantage of protecting the film layer 101 from scratches.

[0076] In the above embodiments, the first interference pigment and the second interference pigment each contain a plurality of first titanium dioxide-coated micas and a plurality of second titanium dioxide-coated micas. However, it is sufficient that at least one of the first interference pigment and the second interference pigment contains a plurality of first titanium dioxide-coated micas and a plurality of second titanium dioxide-coated micas. Furthermore, in the above embodiments, the first color pigment chips are first interference pigments of two colors. However, the first color pigment chips may be first interference pigments of three or more colors. Furthermore, first interference pigments of multiple colors may be mixed.

[0077] [Experimental Example] Here, experimental examples will be used to explain the tendency of the appearance of images and patterns on an LCD monitor depending on the particle size of the titanium dioxide-coated mica contained in the pattern printed layer. As shown in Figure 7 and Experimental Examples 1 to 3 described below, printed layers were prepared with adjusted particle size of the titanium dioxide-coated mica. Figure 7 is a diagram showing the configuration of the printed layer in Experimental Examples 1 to 3. An LCD monitor was placed on the back side (transparent smoke printed layer side) of the printed layer in Experimental Examples 1 to 3. The distance between the printed layer and the LCD monitor was 2 mm. The visibility of the LCD monitor when it was turned on and off (items 1 to 4 described below) was evaluated. Sensory evaluation was conducted by four people for items 1 to 4, and the average score was calculated.

[0078] <Experimental Example 1> A printed layer was prepared by sequentially providing a first-color pattern layer, a second-color pattern layer, a white pattern layer, and a transparent smoke printed layer on a transparent PET substrate. In Experimental Example 1, the first-color pattern layer was formed by screen printing using an ink containing a first-color binder (urethane resin) and red and gold interference pigments dispersed within the first-color binder. The red and gold interference pigment contents were as follows, per 100 parts by weight of the first-color binder: 8 parts by weight of a red interference pigment having a particle size of 10 to 40 μm, 2 parts by weight of a red interference pigment having a particle size of 5 to 25 μm, 5 parts by weight of a gold interference pigment having a particle size of 10 to 60 μm, and 2 parts by weight of a gold interference pigment having a particle size of 5 to 25 μm.

[0079] In Experimental Example 1, a second color pattern layer was formed by screen printing using an ink containing a second color binder (urethane resin) and a green interference pigment dispersed within the second color binder. The green interference pigment content was 4 parts by weight of a green interference pigment with a particle size of 10 to 40 μm and 1 part by weight of a green interference pigment with a particle size of 5 to 25 μm, relative to 100 parts by weight of the second color binder. The red interference pigment, gold interference pigment, and green interference pigment were all titanium dioxide-coated mica.

[0080] In Experimental Example 1, a white pattern layer was formed by screen printing using an ink containing a silver binder (urethane resin) and silver pigment chips dispersed within the silver binder. The silver pigment chip content was 1 part by weight of silver pigment chips with particle sizes of 5 to 25 μm per 100 parts by weight of the silver binder. Furthermore, a transparent smoke print layer was formed by screen printing using an ink containing a medium ink and a black ink in a ratio of 40:1.

[0081] <Experimental Example 2> A printed layer was prepared by sequentially depositing a first-color pattern layer, a second-color pattern layer, a white pattern layer, and a transparent smoke printed layer on a transparent PET substrate. In Experimental Example 2, the first-color pattern layer was formed by screen printing using an ink containing a first-color binder (urethane resin) and red and gold interference pigments dispersed within the first-color binder. The red and gold interference pigment contents were as follows, per 100 parts by weight of the first-color binder: 8 parts by weight of a red interference pigment having a particle size of 10 to 40 μm, 2 parts by weight of a red interference pigment having a particle size of 5 to 25 μm, 5 parts by weight of a gold interference pigment having a particle size of 10 to 60 μm, and 2 parts by weight of a gold interference pigment having a particle size of 5 to 25 μm.

[0082] In Experimental Example 2, a second color pattern layer was formed by screen printing using an ink containing a second color binder (urethane resin) and a green interference pigment dispersed within the second color binder. The content of the green interference pigment was 4 parts by weight, with a particle size of 10 to 40 μm, for every 100 parts by weight of the second color binder. The red interference pigment, gold interference pigment, and green interference pigment were all titanium dioxide-coated mica.

[0083] In Experimental Example 2, a white pattern layer was formed by screen printing using an ink containing a silver binder (urethane resin) and silver pigment chips dispersed within the silver binder. The silver pigment chip content was 1 part by weight of silver pigment chips with particle sizes of 5 to 25 μm per 100 parts by weight of the silver binder. Furthermore, a transparent smoke print layer was formed by screen printing using an ink containing a medium ink and a black ink in a ratio of 40:1.

[0084] <Experimental Example 3> A printed layer was prepared by sequentially providing a first color pattern layer, a second color pattern layer, and a transparent smoke printed layer on a transparent PET substrate. In Experimental Example 3, the first color pattern layer was formed by screen printing using an ink containing a first color binder (urethane resin) and a green interference pigment dispersed within the first color binder. The green interference pigment content was 4 parts by weight of a green interference pigment having a particle size of 10 to 40 μm and 1 part by weight of a green interference pigment having a particle size of 5 to 25 μm, relative to 100 parts by weight of the first color binder.

[0085] In Experimental Example 3, a second color pattern layer was formed by screen printing using an ink containing a second color binder (urethane resin) and red and gold interference pigments dispersed within the second color binder. The red and gold interference pigment contents were 8 parts by weight of red interference pigment with a particle size of 10 to 40 μm and 5 parts by weight of gold interference pigment with a particle size of 10 to 60 μm, relative to 100 parts by weight of the second color binder.

[0086] In Experimental Example 3, a transparent smoke print layer was formed by screen printing using a mixture of medium ink and black ink in a ratio of 40:1.

[0087] <Item 1: Clarity of displayed content> When the power of the LCD monitor was turned on, the clarity of the images and characters displayed on the LCD monitor was evaluated. <Score> 5 points: The image has little presence compared to the image and text displayed on the LCD monitor, and the image and text appear clear. 3 points: The image is somewhat strong compared to the image and text displayed on the LCD monitor, and the image appears to overlap the image and text slightly. 1 point: The image has a strong presence compared to the image and text displayed on the LCD monitor, and the image appears to overlap the image and text.

[0088] <Item 2: Brightness of the displayed content> When the power of the LCD monitor was turned on, the brightness of the images and characters displayed on the LCD monitor was evaluated. <Score> 5 points: Images and text displayed on the LCD monitor appear bright. 3 points: Images and text displayed on the LCD monitor appear slightly dark. 1 point: The image and text displayed on the LCD monitor appear quite dark.

[0089] <Item 3: Effects of black LCD monitors> The influence of the black LCD monitor on the image was evaluated when the LCD monitor was turned off. <Score> 5 points: There is no influence of the black color of the LCD monitor, and the image is clearly visible. 3 points: The influence of the black color of the LCD monitor is slightly noticeable, making the image appear slightly dark and muted (slightly high transparency). 1 point: The influence of the black color of the LCD monitor is evident, making the image appear quite dark and sunken (high transparency).

[0090] <Item 4: Color development of the pattern> The color development of the image was evaluated when the power of the LCD monitor was turned off. <Score> 5 points: The color of the pattern is good. 3 points: The color of the pattern is slightly weak and the color of the pattern appears pale (whitish). 1 point: The color of the pattern is weak and the color of the pattern appears white.

[0091] The results of the sensory evaluation of items 1 to 4 for Experimental Examples 1 to 3 are shown in Table 1 below. Any evaluation of 3 points or higher was deemed acceptable for practical use. Experimental Example 1 showed that the influence of the black LCD monitor on the image was fairly low, and the image visibility tended to be displayed at a sufficiently high level. High evaluation results were also obtained for the color development of the image and the clarity and brightness of the image and text display. Meanwhile, Experimental Examples 2 and 3 showed that the influence of the black LCD monitor on the image was kept low, while the color development of the image and the clarity and brightness of the image and text display tended to be generally good.

[0092] [Table 1] [Explanation of symbols]

[0093] 1...solar cell module, 2, 2A, 2B, 2C...printed layer, 5...picture printed layer, 10...first color pattern layer, 11...first color dot, 12...first color binder, 13...first color pigment chip, 14a, 14b...first interference pigment, 15a, 16a, 25a...first titanium dioxide-coated mica, 15b, 16b, 25b...second titanium dioxide-coated mica, 17a, 17b...first interference light, 20...second color pattern layer, 21...second color dot, 22...second color binder, 23...second color pigment chip, 24...second interference pigment, 26...second interference light, 101...film layer, 102...vapor deposition layer, 104A...top coat layer, 104B...glass layer.

Claims

1. A solar cell; a deposition layer formed by vapor deposition of a metal, the deposition layer being disposed on the light-receiving surface side of the solar cell; a decorative printing layer disposed on an outer layer side of the vapor deposition layer with respect to the light receiving surface, The printing layer is a first color pattern layer formed of a plurality of first color dots; a second color pattern layer provided on the first color pattern layer and configured by a plurality of second color dots; each of the plurality of first color dots includes a first color binder and a plurality of first color pigment chips dispersed within the first color binder; each of the plurality of second color dots includes a second color binder and a plurality of second color pigment chips dispersed within the second color binder; one of the plurality of first color pigment chips and the plurality of second color pigment chips is a first interference pigment of a plurality of colors that generates first interference light different from each other; the other of the plurality of first color pigment chips and the plurality of second color pigment chips is a second interference pigment that generates a second interference light of a single color different from the mixed color exhibited by the plurality of first interference pigments; At least one of the first interference pigment and the second interference pigment comprises a small particle size grade interference pigment having a particle size range of 5 μm to 25 μm and a large particle size grade interference pigment having a particle size range of 25 μm to 40 μm; the small particle size grade interference pigments are arranged so as to fill gaps between the large particle size grade interference pigments, a solar cell module that performs additive color mixing of the plurality of first interference lights and the second interference light;

2. The solar cell module according to claim 1 , further comprising a film layer as an outermost layer on the light-receiving surface.

3. The solar cell module according to claim 1 , further comprising a top coat layer as an outermost layer on the light-receiving surface.

4. The solar cell module according to claim 1 , further comprising a glass layer as an outermost layer for the light-receiving surface.

5. 2. The solar cell module according to claim 1, wherein the vapor deposition layer has a total light transmittance of 25% to 75%.

6. The large particle size grade interference pigment comprises a particle size range of 25 μm to 60 μm. The solar cell module according to claim 1 .

7. At least one of the small particle size grade interference pigment and the large particle size grade interference pigment The other is an interference pigment containing titanium dioxide-coated mica. The solar cell module according to claim 1 .

Images