WO2023238831A1 - Paving photovoltaic module, solar photovoltaic power generation paving block, method for manufacturing paving photovoltaic module, glass plate, and laminated glass for glass floor - Google Patents

Abstract

Provided are a paving photovoltaic module and paving block, capable of ensuring good durability and traveling performance even in actual use environments. This paving photovoltaic module comprises a cover glass, a photovoltaic cell, and a sealing layer for sealing the photovoltaic cell. The cover glass is disposed on the light-receiving surface side of the photovoltaic module. The cover glass has a first side and a second side, and the sealing layer containing the photovoltaic cell is disposed on the second side. The cover glass includes particles protruding from the surface of the cover glass on the first side. The diameters of the particles are 0.01-5 mm.

Description

Photovoltaic module for pavement, solar power generation pavement block, method for manufacturing photovoltaic module for pavement, glass plate, and laminated glass for glass floor

The present invention relates to a photovoltaic module for paving, a solar power generation paving block, a method for manufacturing a photovoltaic module for paving, a glass plate, and a laminated glass for glass floors.

Solar power generation is a power generation method that utilizes the phenomenon that electricity is generated when light hits various materials, such as silicon semiconductors, and directly converts the light energy of the sun into electricity using solar cells (semiconductor elements). Solar power generation has become increasingly important because it uses renewable energy to generate electricity and does not emit or increase greenhouse gas emissions. In addition, governments around the world have implemented policies to introduce solar power, and large-scale solar power generation facilities have been put into operation, increasing the total amount of power generated and achieving a track record of being able to withstand long-term operation.

Therefore, it has been proposed to place photovoltaic modules on the road surface in order to prevent natural destruction and to secure the installation area. For example, Patent Document 1 describes a tile for road construction that has a cavity inside and holds a solar cell inside with an elastic body. Further, Patent Document 2 discloses a photovoltaic module in which a photovoltaic module is attached to one side of a translucent support member made of polycarbonate or the like, and a surface coating layer made of a resin containing fine particles is provided on the other side. is listed.

On the other hand, Patent Document 3 describes a flat substrate on which a glass coating layer is formed by heating a coating film containing a glass frit and particles having a size of 0.5 to 40 μm. Since the softening temperature or melting temperature of these particles is higher than the softening temperature of the glass component, protrusions formed by these particles are formed on the surface of the glass coating layer.

Japanese Patent Application Publication No. 2002-118279 Patent No. 6814445 US Patent No. 10,611,677

However, in the prior art disclosed in Patent Document 1, since a cavity is provided inside the road laying tile, there are problems such as there is a limit to the improvement in load capacity and it is difficult to increase the area.
In addition, the technology described in Patent Document 1 does not take into consideration the slip resistance performance when vehicles and pedestrians pass on the road, and ensures good power generation performance and driving performance even in actual use environments. It was difficult to do so.

Furthermore, in the prior art disclosed in Patent Document 2, a photovoltaic module having a surface coating layer made of a resin containing fine particles had problems with durability, etc. when installed on a vehicle or pedestrian road.

On the other hand, the prior art disclosed in Patent Document 3 is intended to be applied to doors, kitchen furniture, etc., for example, as a translucent panel for interior materials of buildings, and has excellent abrasion resistance, scratch resistance, and thermal stability in the home environment. and meet the requirements of the coating layer, such as chemical resistance. However, when applied in an outdoor environment, particularly as a road pavement surface, there have been problems with the slip resistance performance when vehicles and pedestrians pass on the road.

The present invention has been made in view of the above-mentioned conventional problems, and provides a photovoltaic module for pavement, a solar power generation pavement block, and a pavement block that can ensure good slip resistance performance even in actual use environments. The present invention aims to provide a method for manufacturing a photovoltaic module, a glass plate, and a laminated glass for a glass floor.

The content of this disclosure includes the following embodiments.
[1] Cover glass and
a photovoltaic cell;
a sealing layer that seals the photovoltaic cell;
A pavement photovoltaic module comprising:
arranging the cover glass on the light-receiving surface side of the photovoltaic cell;
the cover glass has a first side and a second side, and the photovoltaic cell is disposed on the second side;
The cover glass includes particles protruding from the surface on the first side,
A photovoltaic module for pavement, wherein the particles have a particle size of 0.01 to 5 mm.
[2] The cover glass includes a particle layer and a glass substrate, the particle layer being disposed on the first side, and the glass substrate being disposed on the second side,
The particle layer includes the particles and a binder,
The binder is a fired glass frit,
The photovoltaic module for paving according to [1], wherein the particles are bonded to the glass substrate using the binder.
[3] The paving light according to [2], wherein the particle layer includes a binder layer formed of the binder on the glass substrate, and the particles are bonded to the glass substrate through the binder layer. Electromotive force module.
[4] The photovoltaic module for pavement according to [2] or [3], wherein the particle layer has bubbles.
[5] The photovoltaic module for pavement according to [4], wherein the number of bubbles contained in the particle layer is 100/mm ³ or more.
[6] The photovoltaic module for paving according to any one of [2] to [5], wherein the particle layer is patterned in a circular, elliptical, polygonal, etc. shape when viewed from above.
[7] The photovoltaic module for paving according to any one of [2] to [6], wherein the composition of the glass substrate and the composition of the binder are different.
[8] The photovoltaic module for pavement according to [7], wherein the strain point of the glass substrate is 30° C. or more higher than the softening point of the binder.
[9] The photovoltaic module for pavement according to any one of [2] to [8], which has the relationship shown in the following formula.
Thermal expansion coefficient of the glass substrate≧thermal expansion coefficient of the binder≧thermal expansion coefficient of the particles [10] The photovoltaic material for pavement according to any one of [2] to [9], wherein the glass substrate is a laminated glass. power module.
[11] The photovoltaic module for pavement according to any one of [1] to [10], wherein the particles are crystalline particles with sharp edges.
[12] The photovoltaic power for paving according to any one of [1] to [11], wherein the density of the particles protruding from the surface of the first side of the cover glass is 1 particle/cm ² or more. module.
[13] Further including a back glass,
The pavement according to any one of [1] to [12], comprising the cover glass, the photovoltaic cell-containing sealing layer having the photovoltaic cell and the sealing layer, and the back glass in that order. Photovoltaic module for use.
[14] The photovoltaic module for paving according to any one of [1] to [13], wherein the surface of the first side of the cover glass has a slip resistance value BPN of 30 or more.
[15] The photovoltaic module for paving according to any one of [1] to [14], wherein the photovoltaic cell includes a single crystal or polycrystalline silicon solar cell.
[16] The photovoltaic module for paving according to any one of [1] to [15], wherein the second surface of the cover glass does not include a layer made of a fired glass frit.
[17] A solar power generation pavement block comprising the pavement photovoltaic module according to any one of [1] to [16].
[18] A method for manufacturing the paving photovoltaic module according to any one of [1] to [16], comprising:
a cover glass manufacturing step of manufacturing the cover glass including the particles protruding from the surface;
A method for manufacturing a photovoltaic module for paving, including a sealing step of sealing the photovoltaic cells included in the sealing layer using the cover glass.
[19] having a first side and a second side,
The first side includes particles protruding from the surface;
A glass plate, wherein the particles have a particle size of 0.01 to 5 mm.
[20] The glass plate includes a particle layer and a glass substrate, the particle layer being disposed on the first side, and the glass substrate being disposed on the second side,
The particle layer includes the particles and a binder,
The binder is a fired glass frit,
The glass plate according to [19], wherein the particles are bonded to the glass substrate using the binder.
[21] The glass plate according to [19] or [20],
An interlayer film for laminated glass,
A laminated glass for a glass floor, comprising a glass substrate for laminated glass and a laminated glass substrate for laminated glass in that order,
A laminated glass for a glass floor, wherein the interlayer film for laminated glass is disposed on the second side of the glass plate.

According to the present invention, there is provided a photovoltaic module for paving that can ensure good skid resistance performance even in an actual use environment, a solar power generation paving block, a method for manufacturing a photovoltaic module for paving, a glass plate, and Laminated glass for glass floors can be provided.

1 is a schematic cross-sectional view showing a structural example of a photovoltaic module for pavement 100 according to an embodiment of the present invention. FIG. 1 is a schematic cross-sectional view showing a structural example of a paving photovoltaic module 110 according to a first embodiment. FIG. 2 is a schematic cross-sectional view showing a structural example of a paving photovoltaic module 120 according to a second embodiment. FIG. 7 is a schematic cross-sectional view showing a structural example of a paving photovoltaic module 130 according to a third embodiment. FIG. 7 is a schematic cross-sectional view showing a structural example of a paving photovoltaic module 140 according to a fourth embodiment. 1 is a schematic cross-sectional view showing a structural example of a solar power generation pavement block 500 according to an embodiment of the present invention. FIG. 3 is a schematic cross-sectional view showing a structural example of a photovoltaic cell-containing sealing layer 70 according to the first embodiment. 1 is an optical micrograph (particle portion) of the light-receiving surface of the photovoltaic module for pavement obtained in Example 1. 1 is an optical microscope photograph (binder layer portion) of the light-receiving surface of the photovoltaic module for pavement obtained in Example 1. 9 is a schematic cross-sectional view for explaining FIG. 8. FIG. 8 is a schematic cross-sectional view showing a first modification of the photovoltaic cell-containing sealing layer 70 according to the present embodiment shown in FIG. 7. FIG. 8 is a schematic cross-sectional view showing a second modification of the photovoltaic cell-containing sealing layer 70 according to the present embodiment shown in FIG. 7. FIG. 8 is a schematic cross-sectional view showing a third modification of the photovoltaic cell-containing sealing layer 70 according to the present embodiment shown in FIG. 7. FIG. FIG. 3 is a schematic cross-sectional view showing a structural example of a first glass plate. It is a schematic cross-sectional view which shows the structural example of a 2nd glass plate. It is a schematic cross-sectional view which shows the structural example of a 3rd glass plate. FIG. 7 is a diagram for explaining Example 6. FIG. 7 is a diagram for explaining Example 6. FIG. 7 is a diagram for explaining Example 6.

Hereinafter, the present invention will be explained in more detail. Note that the present invention is not limited only to the embodiments shown below. Identical or equivalent constituent elements, members, and processes shown in each drawing are denoted by the same reference numerals, and redundant explanations will be omitted as appropriate.

"~" means a value greater than or equal to the value before the description "~" and less than or equal to the value after the description "~".

(Photovoltaic module for pavement)
FIG. 1 is a schematic cross-sectional view showing a structural example of a photovoltaic module 100 for paving according to an embodiment of the present invention. A paving photovoltaic module 100 according to an embodiment of the present invention includes a cover glass 50 and a photovoltaic cell-containing sealing layer 70. The photovoltaic cell-containing sealing layer 70 includes a photovoltaic cell and a sealing layer that seals the photovoltaic cell. A cover glass 50 is disposed on the light-receiving surface side of the paving photovoltaic module 100, and the cover glass 50 has a first side 50a and a second side 50b, and the photovoltaic cell-containing seal is disposed on the second side 50b. A stop layer 70 is disposed. The cover glass 50 includes particles 2 protruding from the surface on the first side 50a. The particle size of the particles 2 is 0.01 to 5 mm.
In addition, the particle size of the present invention is determined by measuring the area of the particle in plan view using a surface image of a cover glass obtained using an optical microscope, etc., and calculating the particle size by measuring the area of the particle in a planar view. It is the diameter. Furthermore, "the particle size of the particles is 0.01 to 5 mm" means that the number of particles with a particle size of 0.01 to 5 mm is 70% or more, preferably 80% or more of the total number of particles, or more. It means preferably 90% or more.
Furthermore, the phrase "the cover glass includes particles protruding from the surface on the first side" of the present invention includes an embodiment in which the surface of the protruding particles is coated. In other words, "the particles protrude from the surface" refers to the particles protruding from the region of the first side surface where no particles are provided, and the surface of the particles is For example, it may be covered with a binder layer (described later), or it may be exposed to the outside without being covered with any other member.
Further, it is preferable that the cover glass 50 does not include particles protruding from the surface on the surface of the second side 50b, and particularly does not include a layer made of a fired glass frit on the surface of the second side 50b. .
The above-mentioned paving photovoltaic module 100 will be described in detail below using the first to fourth embodiments as examples.

[First embodiment]
FIG. 2 is a schematic cross-sectional view showing a structural example of the paving photovoltaic module 110 of this embodiment. The paving photovoltaic module 110 of this embodiment includes a cover glass 51 and a photovoltaic cell-containing sealing layer 70. The photovoltaic cell-containing sealing layer 70 includes a photovoltaic cell and a sealing layer that seals the photovoltaic cell. A cover glass 51 is disposed on the light-receiving surface side of the paving photovoltaic module 100, and the cover glass 51 has a first side 51a and a second side 51b, and the photovoltaic cell-containing seal is disposed on the second side 51b. A stop layer 70 is disposed. The cover glass 51 includes particles 2 protruding from the surface on the first side 51a. The particle size of the particles 2 is 0.01 to 5 mm.

As shown in FIG. 7, the paving photovoltaic module 110 of this embodiment further includes a cover glass 51, a plurality of photovoltaic cells 76, and a seal from the light-receiving surface side of the paving photovoltaic module 110. It is preferable to have a sealing layer 72 (including a first sealing layer 74 and a second sealing layer 78). All of the plurality of photovoltaic cells 76 are sealed with a sealing layer 72.

〔cover glass〕
The cover glass 51 according to the present embodiment includes a particle layer 10 and a glass substrate 20. The particle layer 10 is arranged on the first side 51a, and the glass substrate 20 is arranged on the second side 51b.
On the surface of the first side 51a of the cover glass 51, the slip resistance value BPN is preferably 30 or more, more preferably 40 or more.
A method for evaluating the slip resistance value BPN will be explained in Examples below.

<Particle layer>
The particle layer 10 according to the present embodiment includes the particles 2 and a binder 4. The binder 4 is a fired product of glass frit. The particles 2 are bonded to the glass substrate 20 using the binder. The particle layer 10 includes a binder layer 6 formed of the binder 4 on the glass substrate 20 .

It is preferable that the particle layer 10 (binder layer 6) has air bubbles. It is preferable that the size of the bubbles is less than or equal to the thickness of the binder layer 6.

The number of bubbles contained in the particle layer 10 is preferably at least 100 bubbles/mm ³ , more preferably at least 1×10 ³ bubbles/mm ³ , and more preferably at least 1×10 ⁴ bubbles/mm ³ More preferably, the number is 1×10 ^{5 pieces/mm 3 or more, and most preferably 1×10 5} pieces/mm ³ or more. Further, it is preferable that the number of particles is 1×10 ¹⁰ pieces/mm ³ or less.
The layer thickness of the particle layer 10 is 0.02 to 5 mm, preferably 0.03 to 5 mm, more preferably 0.05 to 5 mm, and even more preferably 0.1 to 5 mm. preferable.

It is preferable that the thickness of the binder layer 6 in the peripheral part of the particles 2 is thicker than in the part away from the particles 2. That is, for example, as shown in FIGS. 8 and 10 of Example 1, it is preferable that a swell of the particle layer 10 is formed around the particles 2.

<<particles>>
As the particles 2 according to the present embodiment, crystalline particles, glass particles, ceramic particles, etc. can be used. Crystalline particles are preferred from the viewpoint of slip resistance and durability required as a road surface. Examples of the crystalline particles include crystalline particles of oxides such as SiO ₂ , Al ₂ O ₃ , and ZrO ₂ .
Further, in the particle layer 10, glass particles may be used from the viewpoint of affinity with the binder 4 and the glass substrate 20. The composition of the glass particles (referred to as the third glass) is preferably different from the composition of the glass frit of the binder 4 (referred to as the second glass). It is more preferable that the strain point of the third glass is higher than the softening point of the second glass by 30° C. or more.

The particle size of the particles 2 according to this embodiment is 0.01 to 5 mm, and the lower limit is preferably 0.02 mm, more preferably 0.03 mm, and preferably 0.04 mm. More preferably, it is 0.05 mm. When the particle size of the particles 2 is 0.02 mm or more, a necessary slip resistance value for a road surface can be obtained. Further, the upper limit of the particle size of the particles 2 is preferably 2 mm, more preferably 1 mm. When the particle size of the particles 2 is 5 mm or less, the particles 2 are prevented from falling off the cover glass 51, and sufficient durability can be obtained.
The particles 2 according to this embodiment preferably include particles with a particle size range of 0.05 to 0.5 mm.

The shape of the particles according to this embodiment is not particularly limited, and examples include polygonal, plate-like, rod-like, and irregular shapes. From the viewpoint of obtaining the necessary slip resistance value, it is preferable to have an irregular shape with sharp corners rather than a smooth shape such as a spherical shape. For example, when the particles 2 are crystalline particles of an oxide such as SiO ₂ , Al ₂ O ₃ , or ZrO ₂ , irregularly shaped particles obtained by crushing oxide crystals may be used. For example, when the particles 2 are glass particles, irregularly shaped particles obtained by crushing glass may be used.

At least some of the particles 2 protrude from the first surface of the cover glass 51, but some particles 2 (not shown) may be completely buried in the binder layer 6.
On the surface of the first side of the cover glass 51, the density of the protruding particles 2 is preferably 1 particle/cm ² or more, and preferably 5 particles/cm ² or more with respect to the area of the particle layer 10. is more preferable, and even more preferably 10 pieces/cm ² or more. Moreover, it is preferable that it is 1x10 ^<5> pieces/cm ^<2> or less.
On the surface of the first side of the cover glass 51, the total ratio of the area of the particles 2 in plan view to the area of the particle layer 10 is preferably 1 to 80%. The lower limit is more preferably 10%, and even more preferably 20%.

<<Binder layer>>
The binder layer 6 according to the present embodiment includes a binder 4 that is a fired product of glass frit. This layer is formed by firing a coating layer containing glass frit.
The composition of the glass frit (referred to as second glass) is preferably different from the composition of the glass substrate 20 (referred to as first glass), which will be described later, and the strain point of the first glass is lower than the softening point of the second glass. The temperature is preferably 20°C or more, more preferably 30°C or more, and even more preferably 50°C or more.
Examples of the glass for the glass frit include soda lime silicate glass, borosilicate glass, alkali-free glass, and quartz glass.

It is preferable that the binder layer 6 has air bubbles. The presence of air bubbles may scatter sunlight within the binder layer, increasing the amount of light reaching the photovoltaic cell. It is more preferable that the size of the bubbles is equal to or less than the thickness of the binder layer.
It is further preferable that the number of bubbles contained in the binder layer 6 is 100/mm ³ or more. Note that the number of bubbles was counted as follows. First, the binder layer was polished until it had a thickness of about 15 μm. This is because if the thickness is at this level, all bubbles existing in the thickness direction can be confirmed when observed with an optical microscope. Next, optical microscopic observation was performed, and bubbles with a diameter of 0.5 μm or more within the field of view were identified and counted by image processing. The number of bubbles thus obtained was converted into the number of bubbles per mm ³ by dividing by the binder layer thickness and viewing area. In addition, since the number of bubbles varies depending on the location, the measurement was performed at three arbitrary locations and the average value was taken.
The layer thickness of the binder layer 6 is preferably 10 to 2000 μm, and the lower limit is more preferably 50 μm, even more preferably 100 μm.
The binder layer 6 may include particles 2 having a particle size smaller than the layer thickness of the binder layer 6 within the layer.

<Glass substrate>
As the glass substrate 20 according to this embodiment, a glass plate can be mentioned. Specific examples of materials constituting the glass plate include soda lime silicate glass, quartz glass, crystal glass, alkali-free glass, aluminosilicate glass, borosilicate glass, and barium borosilicate glass. Soda lime silicate glass with reduced iron content is preferred.
Specific examples of soda lime silicate glass include 60 to 75% by mass of SiO ₂ , 0 to 3% by mass of Al ₂ O ₃ , 0 to 15% by mass of CaO, 0 to 12% by mass of MgO, and glass having a composition of 5 to 20% by mass Na ₂ O. Here, SiO ₂ is the main component of soda lime silicate glass.
In addition to the above materials, the soda lime silicate glass may further contain at least one material selected from the group consisting of K ₂ O, TiO ₂ , ZrO ₂ , SrO, BaO and LiO ₂ .
Moreover, the soda lime silicate glass may further contain a refining agent (eg, SO ₃ , SnO ₂ , Sb ₂ O ₃ ).

The glass substrate 20 may be laminated glass. Laminated glass has a structure in which a pair of glass plates are integrated by interposing an interlayer film such as resin between them and adhering them together. The laminated glass is not particularly limited, and any known laminated glass can be used. The thickness and number of layers of the glass plate included in the laminated glass; the material, thickness, etc. of the interlayer film included in the laminated glass are not particularly limited, and may be the same as those of known laminated glasses.

It is preferable that the glass substrate 20 is a tempered glass that has been subjected to a strengthening process. The glass substrate 20 made of tempered glass is preferable because it is less likely to break than the glass substrate 20 that has not been subjected to a strengthening process. The tempered glass plate includes, for example, a surface layer having residual compressive stress, a back layer having residual compressive stress, and an intermediate layer formed between the front layer and the back layer and having residual tensile stress. is used.
Specific examples of the strengthening treatment include chemical strengthening treatment performed by a known ion exchange method or the like, and physical strengthening treatment performed by a known air cooling strengthening method or the like. A chemically strengthened glass plate has sufficient strength even if the plate thickness is thin because the residual compressive stress value of the front layer or back layer can be increased. On the other hand, if the plate thickness is about 3 mm or more, physical strengthening treatment is effective.
However, it may be preferable that the glass substrate 20 is not subjected to any strengthening treatment. For example, if the glass substrate 20 is not strengthened, spider web-like cracks are suppressed when the glass substrate 20 is broken. Therefore, even if the glass substrate 20 is broken, the increase in light scattering and the reduction in light reaching the cell can be suppressed, and a decrease in power generation efficiency can be suppressed. Further, even if the glass substrate 20 is not strengthened, by using laminated glass, for example, scattering of fragments can be suppressed.

The glass substrate 20 may be surface-treated from the viewpoint of adhesion to a photovoltaic cell-containing sealing layer 70 (for example, a first sealing layer 74 in FIG. 7, which will be described later), which will be described later. As the surface treatment method, known methods can be used, including activation treatment (plasma method, vapor deposition method, acid treatment, base treatment, etc.), chemical conversion treatment, material surface polishing, sanding treatment, pore sealing treatment, blasting treatment, and primer treatment. Examples include processing.
Specific examples of the primer include silane coupling agents (especially alkoxysilanes, etc.), epoxy resins, (meth)acrylic resins, and polyester resins.

The concentration of Fe ₂ O ₃ in the glass substrate 20 is preferably less than 1000 ppm, more preferably less than 500 ppm, and even more preferably less than 100 ppm, expressed as a mass percentage on an oxide basis. If the Fe ₂ O ₃ content is within the above range, absorption of near-infrared light by Fe ₂ O ₃ can be suppressed, resulting in high transmittance in the near-infrared light region and improved power generation efficiency. Therefore, the glass substrate 20 with an Fe ₂ O ₃ content of less than 1000 ppm is suitable for the photovoltaic cell-containing sealing layer 70 having the photovoltaic cell 76 with high spectral sensitivity to near-infrared light.
Here, the content of Fe ₂ O ₃ in this specification means the content when the total iron content contained in the glass substrate 20 is converted into Fe ₂ O ₃ , and is determined by fluorescent X-ray measurement method. It will be done.

The thickness of the glass substrate 20 can be arbitrarily set depending on the type of road to be laid. The thickness of the glass substrate 20 is preferably 1 to 70 mm, the lower limit is more preferably 3 mm, even more preferably 10 mm, and particularly preferably 15 mm. If the thickness is within the above range, durability will be high and the glass substrate 20 will be difficult to break. If the thickness is 70 mm or less, the glass substrate 20 will be lightweight, so the installation work of the paving photovoltaic module 110 of this embodiment can be performed more suitably.
The thickness of the glass substrate 20 is the arithmetic mean value of the thicknesses obtained by measuring the cover glass using a thickness meter.

It is preferable that the coefficient of thermal expansion of the glass substrate 20 is expressed by the following equation as the relationship between the binder 4 and the particles.
Thermal expansion coefficient of glass substrate≧thermal expansion coefficient of binder≧thermal expansion coefficient of particles If the thermal expansion coefficient of the glass substrate 20 has the above relationship, even after firing and cooling in the manufacturing process of the cover glass 51 described below, The particles 2 are strongly fixed to the surface of the cover glass 51, and sufficient durability can be obtained.

[Photovoltaic cell-containing sealing layer]
FIG. 7 is a schematic cross-sectional view showing one aspect of the photovoltaic cell-containing sealing layer 70 according to this embodiment. The photovoltaic cell-containing sealing layer 70 includes a photovoltaic cell 76 and a sealing layer 72 (including a first sealing layer 74 and a second sealing layer 78) that seals the photovoltaic cell 76. ,including. The photovoltaic cell-containing sealing layer 70 according to the present embodiment includes, from the light-receiving surface side of the photovoltaic cell-containing sealing layer 70, a first sealing layer 74, a plurality of photovoltaic cells 76, and a second and a sealing layer 78 in this order.
The first sealing layer 72 contains resin. The resin in the first sealing layer is at least one resin selected from the group consisting of olefin resin (especially ethylene-vinyl acetate copolymer (EVA resin)), polyvinyl butyral resin (PVB resin), ionomer resin, and silicone resin. In terms of adhesion between the cover glass and the design layer, at least one resin selected from the group consisting of ethylene-vinyl acetate copolymer and polyvinyl butyral resin is particularly preferred.

The first sealing layer 74 is preferably transparent. If the first sealing layer 74 is transparent, for example in the case of FIG. 1, the light transmitted through the cover glass 50 will easily reach the first light receiving surface 76A of the photovoltaic cell 76.

The thickness of the first sealing layer is preferably 50 to 2,000 μm, preferably 70 to 1,500 μm, more preferably 100 to 1,200 μm, and preferably 150 to 1,000 μm. It is particularly preferable that there be. When the thickness of the first sealing layer is 50 μm or more, the ultraviolet ray absorption efficiency is excellent and the durability is excellent. If the thickness of the first sealing layer is 2,000 μm or less, it is economical and has excellent robustness as a building material because deformation of the first sealing layer is suppressed.

The first sealing layer is formed by laminating the first sealing material with another material and bonding them under heat and pressure. The first sealing material may contain the resin described above. The first sealing material preferably contains an uncrosslinked resin and a crosslinking agent from the viewpoint of weather resistance of the first sealing layer. In this case, the uncrosslinked resin and the crosslinking agent in the first sealing material react with each other by heat and pressure bonding, and a first sealing layer containing the crosslinked resin is obtained.
As the crosslinking agent, known crosslinking agents such as organic peroxides can be used.
The first sealing material is preferably in the form of a film or a sheet when laminated.

The photovoltaic cell 76 according to this embodiment has a function of converting light energy received by the first light receiving surface 76A of the photovoltaic cell into electrical energy. The photovoltaic cell may have this function only on one light-receiving surface, or may have this function on the other light-receiving surface.

Specifically, the photovoltaic cell 76 includes a silicon-based solar cell composed of single crystal silicon, polycrystalline silicon, or an amorphous silicon type solar cell, and GaAs, CIS, CIGS, CdTe, InP, Known solar cells can be used, such as a compound solar cell composed of Zn ₃ P ₂ or Cu ₂ S, or an organic solar cell such as a perovskite type or a dye-sensitized type. Single-crystalline or polycrystalline silicon-based solar cells, CIS-based solar cells, and CIGS-based solar cells are more preferred, and single-crystalline silicon-based solar cells are most preferred.

Preferable aspects such as materials and contents contained in the second sealing layer 78 are the same as those of the first sealing layer. The thickness of the second sealing layer 78 is not particularly limited, but is preferably 50 to 2,000 μm, more preferably 70 to 1,500 μm, and even more preferably 100 to 1,200 μm. Particularly preferred is 150 to 1,000 μm. If the thickness of the second sealing layer 78 is 50 μm or more, it will be easy to follow the unevenness of the photovoltaic cell or wiring. If the thickness of the second sealing layer is 2,000 μm or less, it is economical and also has excellent robustness as a building material because deformation of the second sealing layer is suppressed.　

<Modifications of photovoltaic cell-containing sealing layer>
FIG. 11 is a schematic cross-sectional view showing a first modification of the photovoltaic cell-containing sealing layer 70 according to the present embodiment shown in FIG.
The photovoltaic cell-containing sealing layer 70A shown in FIG. 11 uses a solar cell module 176 instead of the photovoltaic cell 76 of the photovoltaic cell-containing sealing layer 70 shown in FIG. and a sealing layer 72 (including a first sealing layer 74 and a second sealing layer 78) that seals the solar cell module 176. The solar cell module 176 is not particularly limited, but an existing solar cell module can be used. The solar cell module 176 includes, for example, a second cover glass 81, a third sealing layer 84 that seals the photovoltaic cell 76, and a second back glass 82. As the second cover glass 81, the second back glass 82, and the third sealing layer 84, known ones can be used. Note that the second back glass 82 does not need to be made of glass, but may be a sheet-like material made of PET or the like.

FIG. 12 is a schematic cross-sectional view showing a second modification of the photovoltaic cell-containing sealing layer 70 according to the present embodiment shown in FIG.
The photovoltaic cell-containing sealing layer 70B shown in FIG. 12 uses a solar cell module 276 instead of the photovoltaic cell 76 of the photovoltaic cell-containing sealing layer 70 shown in FIG. There is no structure of the sealing layer 78, and the solar cell module 276 and the sealing layer 72 (including only the first sealing layer 74) that seals the solar cell module 276 are included. The solar cell module 276 is not particularly limited, but an existing solar cell module can be used. The solar cell module 276 includes, for example, a second cover glass 81, a third sealing layer 84 that seals the photovoltaic cell 76, and a second back glass 82. As the second cover glass 81, the second back glass 82, and the third sealing layer 84, known ones can be used. Note that the second back glass 82 does not need to be made of glass, but may be a sheet-like material made of PET or the like.

FIG. 13 is a schematic cross-sectional view showing a third modification of the photovoltaic cell-containing sealing layer 70 according to the present embodiment shown in FIG.
The photovoltaic cell-containing sealing layer 70C shown in FIG. 13 uses a solar cell module 376 instead of the photovoltaic cell 76 of the photovoltaic cell-containing sealing layer 70 shown in FIG. There is no structure of the sealing layer 78, and the solar cell module 376 and the sealing layer 72 (including only the first sealing layer 74) that seals the solar cell module 376 are included. The solar cell module 376 is not particularly limited, but an existing solar cell module can be used. The solar cell module 376 includes, for example, a second cover glass 81 , a photovoltaic cell 76 formed by forming a thin film on the second cover glass 81 , and a third seal that seals the photovoltaic cell 76 . A stop layer 84 and a second back glass 82 are included. As the second cover glass 81, the second back glass 82, and the third sealing layer 84, known ones can be used. Note that the second back glass 82 does not need to be made of glass, but may be a sheet-like material made of PET or the like.
The difference between the third modification and the second modification shown in FIG. 12 is that a sealing layer is not included between the second cover glass 81 and the photovoltaic cell 76. For example, when using a thin film type solar cell (amorphous silicon, compound type, organic type, etc.) as the photovoltaic cell 76, a thin film is formed on the second cover glass 81. Therefore, the third sealing layer 84 forms only one side of the photovoltaic cell 76, as shown in FIG.

[Method for manufacturing photovoltaic modules for pavement]
The method for manufacturing the paving photovoltaic module of this embodiment from the cover glass 51 of this embodiment and the solar power generation module 70 of this embodiment includes, for example, the cover glass manufacturing step S1 of manufacturing the cover glass 51. and a sealing step S2 of sealing the photovoltaic cell 76 using a cover glass 51 by a known method.

<Cover glass manufacturing process S1>
The cover glass manufacturing step S1 according to the present embodiment includes a step S1-1A of forming a layer of glass frit, which is a raw material for the binder 4, on the surface of the first side 51a of the glass substrate 51, and a step S1-1A in which the particles 2 are A step S1-2A of embedding the glass frit layer obtained in the step S1-1A in a state where it partially protrudes from the surface, and a step S1-3A of firing the substrate obtained in the step S1-2A. is preferred.
In the step S-1A, as a method for forming a layer of glass frit, for example, a frit paste containing the glass frit, a solvent, a resin, a filler, etc. is prepared, and this paste is applied to a predetermined area on the surface of the first side 51a. An example of this method is to apply the film to a thickness of . An overview of the technology is shown below.

(Frit paste material)
1. Glass Frit Glass frit particle size is 1 μm to 10 μm. Fillers are sometimes added to control the hardness and thermal expansion of the fired film. Specifically, zircon, zirconia, silica, alumina, etc. are used as the filler, and the particle size is 0.1 μm to 20 μm.

2. Resin Resin supports the glass frit and filler in the coating after printing. Specific examples include ethyl cellulose, nitrocellulose, acrylic resin, vinyl acetate, butyral resin, melamine resin, alkyd resin, and rosin resin. Ethyl cellulose, nitrocellulose, and acrylic resin are used as the main resin. Note that butyral resin, melamine resin, alkyd resin, and rosin resin are used as additives to improve the strength of the coating film. The binder removal temperature during firing is 350°C to 400°C for ethylcellulose, 200°C to 300°C for nitrocellulose, and 300°C to 350°C for acrylic.

3. Solvent Dissolves the resin and adjusts the viscosity required for printing. Also, it does not dry during printing and dries quickly during the drying process. One with a boiling point of 200°C to 230°C is desirable. Blend and use to adjust viscosity, solid content ratio, and drying speed. Specific examples include ether solvents (butyl carbitol (BC), butyl carbitol acetate (BCA), diethylene glycol di-n-butyl ether, dipropylene glycol butyl ether, tripropylene glycol butyl ether, butyl acetate cellosolve), alcohol solvents (α-terpineol, pine oil, dowanol), ester solvents (2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, butyl acetate), phthalate solvents (DBP (dibutyl phthalate), DMP (dimethyl phthalate), DOP (dioctyl phthalate)). The substances mainly used are α-terpineol and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate). Note that DBP (dibutyl phthalate), DMP (dimethyl phthalate), and DOP (dioctyl phthalate) also function as plasticizers.

4. Others A surfactant may be used to adjust viscosity and promote frit dispersion. A silane coupling agent may be used to modify the surface of the frit.

(Method for making frit paste)
Prepare glass frit and vehicle. Here, the vehicle refers to a mixture of a resin, a solvent, and a surfactant. Specifically, the resin, surfactant, etc. are poured into a solvent heated to 50° C. to 80° C., and then allowed to stand for about 4 to 12 hours, and then filtered.

Next, the glass frit and vehicle are mixed using a planetary mixer. After that, the mixture is kneaded using a kneader to adjust the viscosity. Usually, the glass frit is 70 to 80 wt% and the vehicle is 20 to 30 wt%.

(How to apply frit paste)
The method for applying the frit paste on the surface of the first side 51a is not particularly limited, and any known method can be used. Examples include bar coater printing, applicator printing, doctor blade printing, screen printing, die coat printing, and the like.

In step S1-2A, the particles 2 can be scattered on the surface of the glass frit layer, for example, by using a sieve or the like, or by spraying a mixture of particles and a solvent. Examples include methods.

In the step S1-3A, the printed substrate is fired in a firing furnace. Firing consists of a drying process for the solvent, a debinding process to decompose and eliminate the resin, and a firing process to sinter and soften the glass powder. The debinding temperature is 350° C. to 400° C. for ethyl cellulose, 200° C. to 300° C. for nitrocellulose, and 300° C. to 350° C. for acrylic, and heated in air for 30 minutes to 1 hour. The temperature is then raised to sinter and soften the glass. The firing temperature is from the softening temperature to the softening temperature +200°C, and the shape and size of the bubbles remaining inside vary depending on the processing temperature. Thereafter, the glass film is formed on the substrate by cooling.
Note that a thicker film can be formed using a technique called green sheet printing. A green sheet is obtained by forming a film on a PET film or the like using a doctor blade printing method or a die coat printing method and then drying it. Next, the green sheet is thermocompressed onto the substrate using a roller or the like, and subjected to the same firing process as the frit paste to obtain a fired film. By stacking them together, a thicker glass film can be formed.

The cover glass manufacturing process S1 according to the present embodiment is a process S1-1B of preparing a mixture paste containing glass frit, which is a raw material of the binder 4, and the particles 2 on the surface of the first side 51a of the glass substrate 51. Then, on the surface of the first side 51a of the glass substrate 51, using the mixture paste obtained in S1-1B, the particles 2 are embedded with a portion protruding from the surface of the glass frit layer. It is preferable to include a step S1-2B of forming a layer having the above-mentioned structure, and a step S1-3B of firing the substrate obtained in the step S1-2B.

In the step S1-1B, there is a method of preparing a paste containing the glass frit, the particles 2, a solvent, and a resin.
The solvent, resin, and other ingredients are the same as those described in step S1-1A.
In the paste, the content of the particles 2 is preferably 1 to 70 wt%, more preferably 5 to 50 wt%.

In the step S1-2B, the method for applying the mixture paste on the surface of the first side 51a is not particularly limited, and any known method can be used. For example, it is the same as that described in step S1-1A above.

The step S1-3B is the same as the step S1-3A.

<Sealing process S2>
The process of sealing the photovoltaic cell 76 is, for example, a photovoltaic power generation method described in International Publication No. 2021/106869 ("Solar power generation module, manufacturing method thereof, and architectural exterior wall material using the same"). A method of sealing the photovoltaic cell 76 with reference to the module manufacturing method may be mentioned.
The sealing step S2 of the photovoltaic cell 76 of this embodiment includes, but is not particularly limited to, the cover glass 51 obtained in the cover glass manufacturing process, the first sealing material 74 containing an ultraviolet absorber, and the photovoltaic cell 76. An example of this method is to arrange the power cell 76 and the second sealing material 78 in this order and heat and press them to seal the photovoltaic cell 76.
Thereby, the photovoltaic module 110 for paving of this embodiment in which the cover glass 51, the first sealing layer 74, the photovoltaic cell 76, and the second sealing layer 78 are laminated in this order is obtained. .
The heating temperature during thermocompression bonding is preferably 100 to 200°C, particularly preferably 130 to 170°C.
The heat-pressing time is preferably 2 to 120 minutes, particularly preferably 5 to 60 minutes.

[Second embodiment]
FIG. 3 is a schematic cross-sectional view showing a structural example of the paving photovoltaic module 120 of this embodiment. The second embodiment differs from the first embodiment in that the particle layer 11 (binder layer 7) according to the present embodiment is patterned into a circular, elliptical, polygonal, etc. shape when viewed from above.
In the pattern of this embodiment, the ratio of the area of the part where the particle layer 11 (binder layer 7) is formed to the total area of the surface of the glass substrate 20 is preferably 2 to 95%. The lower limit is more preferably 5%, even more preferably 10%. The upper limit is more preferably 95%, and even more preferably 90%.
The method for manufacturing the paving photovoltaic module 120 of this embodiment can be performed by the same method as in the first embodiment, in addition to the method for manufacturing the particle layer 11 (binder layer 7).
As a manufacturing method for the particle layer 11 (binder layer 7), for example, when forming the glass frit layer in the first embodiment, screen printing, squeegee printing using a metal mask, and coating liquid metering dispensing device (dispenser) are used. For example, a layer of glass frit having a predetermined pattern may be formed using a method such as the following.

[Third embodiment]
FIG. 4 is a schematic cross-sectional view showing a structural example of the paving photovoltaic module 130 of this embodiment.
In contrast to the paving photovoltaic module 110 of the first embodiment, the paving photovoltaic module 130 of this embodiment does not have a binder layer formed in the particle layer 12, but instead uses the binder 4, Particles 2 are fixed on a glass substrate 20.
The amount and density of particles 2 used are the same as in the first embodiment.
The binder 4 may exist only between the particles 2 and the glass substrate, or may cover part or all of the particles 2.
The method of manufacturing the photovoltaic module for pavement 130 of this embodiment is the same as the method of manufacturing the photovoltaic module for pavement 110 of the first embodiment, except for the method of forming the particle layer 12.
As a method for manufacturing the particle layer 12 according to the present embodiment, for example, first, part or all of the particles 2 are coated with the binder 4, and the coated particles 2 are directly sprinkled on the surface of the glass substrate 20, and then, One example is a method of firing the substrate.

[Fourth embodiment]
FIG. 5 is a schematic cross-sectional view showing a structural example of the paving photovoltaic module 140 of this embodiment.
The difference between the paving photovoltaic module 140 of this embodiment and the paving photovoltaic module 110 of the first embodiment is that it further includes a back glass 80. When having the back glass 80, the cover glass 50 is preferably laminated glass.

[Back glass]
The back glass 80 according to this embodiment may be the same as or different from the glass substrate 20 according to this embodiment. From the viewpoint of unification of manufacturing raw materials, it is preferable to use the same material as the glass substrate 20. That is, the back glass 80 according to this embodiment is preferably the same as the glass substrate 20 described in the first embodiment.

If the back glass 80 according to the present embodiment is different from the glass substrate 20 according to the present embodiment, the back glass 80 according to the present embodiment may be made of soda lime silicate glass, quartz glass, crystal glass, alkali-free glass, or aluminosilicate glass. Examples include glass, borosilicate glass, and barium borosilicate glass. Glasses that are not highly transparent can also be used.

It is preferable that the back glass 80 is a tempered glass that has been subjected to a strengthening process.

The back glass 80 may be surface-treated in terms of adhesion to the photovoltaic cell-containing sealing layer 70 (for example, the second sealing layer 78 in FIG. 7 described above).

The thickness of the back glass 80 can be arbitrarily set depending on the type of road to be constructed. The thickness of the glass substrate 20 is preferably 1 to 70 mm. If the thickness is 1 mm or more, durability is high and the glass substrate 20 becomes difficult to break. If the thickness is 70 mm or less, the back glass 80 will be lightweight, so the installation work of the paving photovoltaic module 110 of this embodiment can be performed more suitably.

It is preferable that the back glass 80 has the same coefficient of thermal expansion as the glass substrate 20.

[Method for manufacturing photovoltaic modules for pavement]
The method of manufacturing the paving photovoltaic module 140 of this embodiment is the same as the manufacturing method of the first embodiment except that it is different from the sealing step S2 of the first embodiment.
The sealing process S2B of the photovoltaic cell 76 of this embodiment includes, but is not particularly limited to, the cover glass 51 obtained in the cover glass manufacturing process, the first sealing layer 74 containing an ultraviolet absorber, and the photovoltaic cell 76. An example of a method is to arrange the cell 76, the second sealing layer 78, and the back glass 80 in this order, and heat and press them to seal the photovoltaic cell 76.
Thereby, the photovoltaic material for pavement according to the present embodiment in which the cover glass 51, the first sealing layer 74, the photovoltaic cell 76, the second sealing layer 78, and the back glass 80 are laminated in this order. A power module 140 is obtained.
The heating temperature during thermocompression bonding is preferably 100 to 200°C, particularly preferably 130 to 170°C.
The heat-pressing time is preferably 2 to 120 minutes, particularly preferably 5 to 60 minutes.

(Solar power generation pavement block)
FIG. 6 is a schematic cross-sectional view showing a structural example of a solar power generation pavement block 500 according to an embodiment of the present invention. The photovoltaic pavement block 500 of the present embodiment is preferably a pavement block (for example, an interlocking block) comprising any one of the paving photovoltaic modules of the present embodiments 1 to 4 described above. The solar power generation pavement block 500 of this embodiment is preferably one in which the paving photovoltaic module 150 of this embodiment is arranged on a known road paving material 200. The photovoltaic pavement block 500 of this embodiment may further include a road adhesive layer (not shown) between the paving photovoltaic module of this embodiment and the road paving material 200. An example of this method is to apply a known road adhesive or the like onto the road paving material 200 and then fix the paving photovoltaic module 150 of this embodiment.
Examples of the road paving material 200 include those made of known materials used for road surfaces. Examples of the material constituting the road paving material 200 include a paving material containing porous ceramic particles and cement. The material constituting the road paving material 200 may be any material as long as it has hardness and durability that allow pedestrians and vehicles to pass through, and examples thereof include asphalt pavement and concrete pavement. The thickness of the road paving material needs to be able to withstand the passage of pedestrians and vehicles. It is preferable to have a thickness of 50 mm or more.

As the road adhesive material, it is preferable to use a resin material that has electrical insulation properties and is easy to apply. For example, epoxy resin can be used. The thickness of the road adhesive (not shown) layer is approximately 1 to 20 mm, as it is necessary to firmly adhere the road paving material and the paving photovoltaic module 150 to ensure mechanical strength. It is preferable.

(Glass plate)
A glass plate according to an embodiment of the present invention (a glass plate according to the present embodiment) has a first side and a second side, and includes particles protruding from the surface on the first side. The glass plate of this embodiment is preferably used as a cover glass of a photovoltaic module for paving.
14, 15, and 16 are schematic cross-sectional views showing structural examples of a first glass plate 551, a second glass plate 552, and a third glass plate 553, respectively. Examples of the glass plates of this embodiment include a first glass plate 551, a second glass plate 552, and a third glass plate 553 shown in FIGS. 14, 15, and 16.

The first glass plate 551 (FIG. 14) according to this embodiment is the same as the cover glass 51 of the photovoltaic module for paving according to the first embodiment shown in FIG. For example, the first glass plate 551 according to the present embodiment includes a particle layer 10 and a glass substrate 20. The particle layer 10 is arranged on the first side 51a. The particle layer 10, the particles 2 and binder layer 6 constituting the particle layer 10, which are included in the first glass plate 551 according to the present embodiment, are included in the cover glass 51 of the photovoltaic module for paving according to the first embodiment. The particle layer 10, the particles 2 and the binder layer 6 constituting the particle layer 10 are the same.
The method for manufacturing the first glass plate 551 according to this embodiment is the same as the method for manufacturing the cover glass 51 of the photovoltaic module for pavement according to the first embodiment.

Similarly, the second glass plate 552 (FIG. 15) according to the present embodiment is the same as the cover glass 52 of the paving photovoltaic module according to the second embodiment shown in FIG. 3. The method for manufacturing the second glass plate 552 according to this embodiment is the same as the method for manufacturing the cover glass 52 of the photovoltaic module for paving according to the second embodiment.

The third glass plate 553 (FIG. 16) according to this embodiment is the same as the cover glass 53 of the photovoltaic module for paving according to the third embodiment shown in FIG. The method for manufacturing the third glass plate 553 according to this embodiment is the same as the method for manufacturing the cover glass 53 of the photovoltaic module for paving according to the third embodiment described above.

The glass plate of this embodiment has an excellent anti-slip surface, so in addition to being used as a cover glass for photovoltaic modules for pavement, it can also be used for glass floors in buildings and glass tables used as furniture. It may also be used as a glass plate suitable for use in places where high performance is required.

(Laminated glass for glass floors)
The laminated glass for a glass floor of one embodiment of the present invention (the laminated glass for a glass floor of this embodiment) is a laminated glass that can be used as a glass floor. The laminated glass for a glass floor of this embodiment is formed by laminating the above-described glass plate of this embodiment, an interlayer film for laminated glass, and a glass substrate for laminated glass in that order. The interlayer film for laminated glass is disposed on the second side of the glass plate.

[Glass plate]
Examples of the glass plate according to this embodiment include the glass plate of this embodiment described above and the glass plate of its preferred embodiment.

[Interlayer film for laminated glass]
The interlayer film for laminated glass according to this embodiment is not particularly limited, and any known interlayer film for laminated glass can be used. Examples of the interlayer film for laminated glass according to this embodiment include resins such as polyvinyl butyral containing materials that increase sound insulation, materials that increase heat ray reflection, and the like.

[Glass substrate for laminated glass]
The glass substrate for laminated glass according to this embodiment is not particularly limited, and a glass plate used for known laminated glass can be used. The glass substrate for laminated glass according to this embodiment can use the back glass described in the fourth embodiment of the photovoltaic module for paving of the present invention and its preferred embodiment.

[Example]
EXAMPLES Hereinafter, the present invention will be explained in detail with reference to Examples, but the present invention is not limited thereto.
(Slip resistance value BPN)
The slip resistance value BPN was measured according to ASTM E303 using a device manufactured by Daiwa Kenko Co., Ltd.

(Particle size of particle 2)
Sea sand obtained from Fuji Film Wako Pure Chemical Industries, Ltd. and having a particle size of 425 to 850 μm was used.

(particle density)
The particle density was calculated by dividing the total mass of the scattered particles by the mass per particle to calculate the total number of particles, and then dividing it by the area of the particles to calculate the number per cm ² . Here, the mass per particle is an approximate mass calculated by calculating the volume from the particle size of the particle and multiplying it by the density. In this example, since the particle size of the particles is sufficiently large compared to the thickness of the binder layer, it is considered that all of the scattered particles protrude from the surface.

(material)
Particles: manufactured by Fuji Film Wako Pure Chemical Industries, Ltd., sea sand, particle size 425-850 μm
Glass frit: manufactured by AGC Electronics Co., Ltd., ASF6003, softening point: 565°C
Solvent: Butyl acetate Resin: Acrylic binder for sintering KC-7000F, manufactured by Kyoeisha Chemical Co., Ltd.
Dispersant: BYK-Chemie, BYK180
Glass substrate: soda lime glass, size: 220 x 120 mm, thickness: 5 mm, softening point: 740°C
Photovoltaic cell: Single crystal silicon solar cell First and second sealing material: VistaSolar, 521,68

(Example 1)
"Manufacture of photovoltaic modules for pavement"
(I) Cover glass manufacturing process S1
First, a resin and a solvent were weighed so that the resin ratio was 30% by mass, and mixed using a homogenizer while being boiled in boiling water to prepare a vehicle. Next, 40 g of glass frit, 11.3 g of solvent, and 0.6 g of dispersant were mixed using a planetary mixer, and then 6.72 g of vehicle was added and further mixed to prepare a frit paste.
The prepared glass frit paste was applied to one surface of a glass substrate using a bar coater. The coating amount was adjusted so that the thickness of the binder layer after firing was 60 μm.
On top of the glass frit layer, 1.0 g of particles were sprinkled by hand while visually checking so that they were spread evenly within the surface.
The obtained substrate was placed in a firing furnace, and the temperature was first raised from room temperature to 250°C over 1.5 hours in an air atmosphere to volatilize the solvent, and then the temperature was raised to 400°C over 4 hours. The resin was decomposed and disappeared by holding at ℃ for 4 hours, and the temperature was further increased to 680℃ over 40 minutes, and the glass frit was melted and sintered by holding at 680℃ for 10 minutes, and then the temperature was naturally cooled in the furnace. I let it happen. A cover glass was thus obtained.

(II) Sealing process S2
A paving photovoltaic module was manufactured using the cover glass, glass substrate (as a back glass), and solar cell obtained in step S1. As shown in FIGS. 5 and 7, the photovoltaic cell 76 is sealed by the method described in the first embodiment, and a cover glass 51 including the particle layer 10, the photovoltaic cell 76, and a back glass 80 are sealed. A paving photovoltaic module P-1 having a power generation module 40 containing the following was manufactured.
An optical microscope photograph of the light-receiving surface of the paving photovoltaic module P-1 obtained in this example was taken. In addition, the slip resistance value BPN was measured. The results are shown in Table 1 and FIGS. 8 and 9. From the results shown in FIGS. 8 and 9, it was observed that the binder layer contained air bubbles.
FIG. 10 is a schematic cross-sectional view for explaining FIG. 8. Regarding the relationship between the particles and the binder layer in FIG. 8, as shown in the schematic cross-sectional view in FIG. 10, swelling of the binder layer was observed around the particles. Even though the binder layer (FIG. 9) was thin, the particles were well fixed to the glass substrate because of the raised areas around the particles.

(Example 2)
"Manufacture of photovoltaic modules for pavement"
A paving photovoltaic module P-2 was manufactured in the same manner as in Example 1, except that the particle density was (2.5 g). Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 3)
"Manufacture of photovoltaic modules for pavement"
A paving photovoltaic module P-3 was manufactured in the same manner as in Example 1, except that the binder layer thickness was 180 μm. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 4)
"Manufacture of photovoltaic modules for pavement"
A paving photovoltaic module P-4 was manufactured in the same manner as in Example 2, except that the binder layer thickness was 180 μm. Evaluation was performed in the same manner as in Example 1, and the results are shown in Table 1.

(Example 5)
"Optical properties of cover glass (Steps S1-1A, S1-2A, S1-3A)"
In Example 5, the optical properties of the cover glass were evaluated.

(material)
Particles: manufactured by Fuji Film Wako Pure Chemical Industries, Ltd. Sea sand: manufactured by Fuji Seisakusho Co., Ltd. Alumina particles (product name: Fuji Random WA)
Glass frit: manufactured by AGC Electronics Co., Ltd., YFT-531E, softening point: 589°C, thermal expansion coefficient: 76 × 10 ^-7 /°C (50°C - 350°C)
Solvent: Butyl acetate Resin: Acrylic binder for sintering KC7000, manufactured by Kyoeisha Chemical Co., Ltd.
Dispersant: BYK-Chemie, BYK180
Glass substrate: soda lime glass, size: 65 x 150 mm, thickness: 3 mm, softening point: 740°C, strain point: 510°C, coefficient of thermal expansion: 85 x 10 ^-7 /°C (50°C - 350°C)

Vehicles were made as in the previous examples. Next, 20 g of glass frit, 7.65 g of solvent, and 0.40 g of dispersant were mixed using a planetary mixer, and then 3.36 g of vehicle was added and further mixed to prepare a frit paste.
The prepared frit paste was coated on one surface of a glass substrate in the same manner as in the previous example, and 0.5 g of particles were sprinkled thereon by hand while visually checking to ensure that they spread uniformly within the surface. Table 2 shows the types of particles used.
The obtained substrate was fired in the same manner as in the above example to obtain a cover glass.

In order to examine the optical properties of the cover glass thus obtained, haze and total light transmittance were measured. The device used was a haze meter HM-150L2N manufactured by Murakami Color Research Institute Co., Ltd. Since the particles were spread manually and the particle density varied within the plane, measurements were performed on two samples and the average value was taken. The results are shown in Table 2.

(Example 6)
"Laminated glass for glass floors (process S1-1B, S1-2B, S1-3B)"
In Example 6, laminated glass for glass floors was evaluated. 17 to 19 are diagrams for explaining the sixth embodiment.

(material)
Particles: Fuji Seisakusho Co., Ltd. Alumina particles Fuji Random WA Particle number 60 (center particle size 250-212 μm), particle number 120 (center particle size 125-90 μm), particle number 180 (center particle size 63-53 μm)
Glass frit: manufactured by AGC Electronics Co., Ltd., YFT-531E, softening point: 589°C
Solvent: Butyl carbitol acetate (BCA)
Resin: Acrylic binder for sintering KC-1700P manufactured by Kyoeisha Chemical Co., Ltd.
Dispersant: BYK-Chemie, BYK180
Glass substrate: soda lime glass, size: 180 x 200 mm, thickness: 5 mm, softening point: 740°C
Back glass: soda lime glass, size: 180 x 200mm, thickness: 5mm
Interlayer film for laminated glass: VistaSolar, EVA resin, 521,68

In order to pattern-print the frit paste on one surface of a glass substrate, a metal mask having openings in the desired pattern shape was first prepared. Next, the resin and solvent were weighed so that the resin ratio was 40% by mass, and mixed using a homogenizer to prepare a vehicle. Further, 25 g of the obtained vehicle, 1 g of dispersant, 32.73 g of frit, and 17.27 g of particles with particle number 120 were mixed using a planetary mixer to prepare a frit paste. At this time, the volume ratio of particles in the solid content including the frit and particles is 40%. Similarly, frit pastes with a volume ratio of 30% and 50% were produced, and further frit pastes with a volume ratio of 50% were produced using particles with particle numbers 60 and 180.
Next, a metal mask was placed on the glass substrate, an appropriate amount of frit paste was dripped from above, and a urethane squeegee was moved while pressing against the metal mask to embed the frit paste into the mask opening without any gaps, and then the metal mask was removed. . In this way, a pattern of frit paste was formed on the glass substrate. The four patterns used this time are shown in Table 3. Note that the thickness of the metal mask used was 1.0 mm and 0.5 mm.
Note that the length, width, and pitch of the striped steel plates in Table 3 were measured as shown in FIG. 17. Further, the length and width of the dots in Table 3 refer to the diameter of the dots, and the pitch of the dots is the distance between the center positions of adjacent dots.
The obtained substrate was placed in a firing furnace, and the temperature was first raised from room temperature to 250°C over 1.5 hours in an air atmosphere to volatilize the solvent, and then the temperature was raised to 400°C over 4 hours. The resin was decomposed and disappeared by holding at ℃ for 4 hours, and then the temperature was allowed to fall naturally in the furnace. Thereafter, the glass frit was melted and sintered by placing it in a belt furnace heated to 680°C. In the belt furnace, it takes 3 minutes to move from the entrance at room temperature to the furnace at 680°C, stays in the furnace for 9 minutes, and then moves from the inside of the furnace to the exit at room temperature over 6 minutes. A cover glass was thus obtained. Table 4 shows the combinations of the particle number, the pattern and thickness of the metal mask, and the volume ratio of particles in the solid content for the produced cover glass.

The surface shape of the laminated glass for glass floors obtained in this example was observed and measured. FIGS. 18 and 19 show a microscopic image and a cross-sectional curve of a patterned sample in a striped steel plate. A surfcom manufactured by Tokyo Seimitsu Co., Ltd. was used to measure the cross-sectional curve. From these results, it was confirmed that irregularities of about several hundred μm were formed on the surface, and it can be said that particles were protruding from the surface. Furthermore, the slip resistance BPN of the obtained samples was measured, and the results shown in the rightmost column of Table 4 were obtained.

(Example 7)
"Photovoltaic module for pavement (2nd embodiment + 4th embodiment)"
In Example 7, a paving photovoltaic module was evaluated.

(material)
Particles: Fuji Seisakusho Co., Ltd. Alumina particles Fuji Random WA Particle number 120 (center particle size 125 to 90 μm)
Glass frit: manufactured by AGC Electronics Co., Ltd., YFT-531E, softening point: 589°C
Solvent: Butyl carbitol acetate (BCA)
Resin: Acrylic binder for sintering KC-1700P manufactured by Kyoeisha Chemical Co., Ltd.
Dispersant: BYK-Chemie, BYK180
Glass substrate: soda lime glass, size: 100 x 100 mm, thickness: 5 mm, softening point: 740°C
Back glass: soda lime glass, size: 100 x 100mm, thickness: 3mm
Photovoltaic cell: Polycrystalline silicon solar cell First and second encapsulant: VistaSolar, EVA resin, 521,68

In the same manner as in Example 6, a frit paste was prepared using particles with particle number 120, in which the volume ratio of particles in the solid content of frit and particles was 40%.
Next, the prepared frit paste was pattern-printed on one surface of the glass substrate in the same manner as in Example 6. A total of five patterns were used: the four types shown in Table 3 and the entire surface coating (solid). Note that the thickness of the mask used was 0.5 mm.
The obtained substrate was fired in the same manner as in Example 6 to obtain a cover glass.
Next, the obtained cover glass, first encapsulant, photovoltaic cell whose power generation efficiency has been measured, second encapsulant, and back glass are laminated in this order, vacuum packaged, and then placed in an oven. The package was heated at 90° C. for 45 minutes for temporary adhesion, and then the packaging material was removed and heated again at 130° C. for 30 minutes using an oven. In this way, a photovoltaic module for pavement was completed. Note that a photovoltaic module using a cover glass with only a glass substrate without a particle layer was also produced as a reference.

The output characteristics of the solar cell were measured for the photovoltaic module obtained in this example. To measure the output characteristics, a solar simulator manufactured by Yamashita Denso Co., Ltd. was used to irradiate simulated sunlight, and a source meter was used to measure the current-voltage characteristics. From the results, the output power Pmax at the optimum operating point where the product of current and voltage is the largest was determined. Furthermore, the change in Pmax value before and after modularization (the change between the photovoltaic cell alone and the state where a cover glass was placed on it) was also calculated. These results are shown in Table 5. Note that, when the cover glass is viewed in plan, the area ratio of the portion not covered by the pattern in the effective area of the photovoltaic cell was expressed as the pattern aperture ratio. It was confirmed that there is a nearly proportional relationship between the pattern aperture ratio and Pmax normalized with the reference.
Note that since the cover glass obtained in this example is the same as a part of Example 6, its slip resistance BPN is also shown in Table 5.

2: Particles 4: Binder 6, 7: Binder layer 10, 11, 12: Particle layer 20: Glass substrate 50, 51, 52, 53: Cover glass 50a: First side 50b: Second side 70: Photovoltaic cell Containing sealing layers 70A, 70B, 70C: Modification example 72 of photovoltaic cell-containing sealing layer: Sealing layer 74: First sealing layer 76: Photovoltaic cell 76A: First light-receiving surface 76B: Second light-receiving surface Surface 78: Second sealing layer 81: Second cover glass 82: Second back glass 84: Third sealing layer 100, 110, 120, 130, 140, 150: Paving photovoltaic module 176, 276, 376 : Solar cell module 200: Road paving material 500: Solar power generation pavement blocks 551, 552, 553: First glass plate, second glass plate, third glass plate

Claims (21)

1. cover glass and
   a photovoltaic cell;
   a sealing layer that seals the photovoltaic cell;
   A pavement photovoltaic module comprising:
   arranging the cover glass on the light-receiving surface side of the photovoltaic cell;
   the cover glass has a first side and a second side, and the photovoltaic cell is disposed on the second side;
   The cover glass includes particles protruding from the surface on the first side,
   A photovoltaic module for pavement, wherein the particles have a particle size of 0.01 to 5 mm.
2. The cover glass includes a particle layer and a glass substrate, the particle layer is disposed on the first side, and the glass substrate is disposed on the second side,
   The particle layer includes the particles and a binder,
   The binder is a fired glass frit,
   The paving photovoltaic module according to claim 1, wherein the particles are bonded to the glass substrate using the binder.
3. The photovoltaic module for paving according to claim 2, wherein the particle layer includes a binder layer formed of the binder on the glass substrate, and the particles are bonded to the glass substrate through the binder layer. .
4. The photovoltaic module for pavement according to claim 2 or 3, wherein the particle layer has air bubbles.
5. The photovoltaic module for paving according to claim 4, wherein the number of bubbles contained in the particle layer is 100/mm ³ or more.
6. The photovoltaic module for paving according to claim 2 or 3, wherein the particle layer is patterned into a circular, elliptical, polygonal, etc. shape when viewed from above.
7. The photovoltaic module for paving according to claim 2 or 3, wherein the composition of the glass substrate and the composition of the binder are different.
8. The photovoltaic module for paving according to claim 2 or 3, wherein the strain point of the glass substrate is 30° C. or more higher than the softening point of the binder.
9. The photovoltaic module for pavement according to claim 2 or 3, which has the relationship shown in the following formula. Thermal expansion coefficient of the glass substrate ≧ Thermal expansion coefficient of the binder ≧ Thermal expansion coefficient of the particles
10. The photovoltaic module for pavement according to claim 2 or 3, wherein the glass substrate is laminated glass.
11. The photovoltaic module for pavement according to claim 1 or 2, wherein the particles are crystalline particles with sharp edges.
12. The photovoltaic module for paving according to claim 1 or 2, wherein the density of the particles protruding on the surface of the first side of the cover glass is 1 particle/cm ² or more.
13. Furthermore, including the back glass,
    The photovoltaic module for paving according to claim 1 or 2, comprising the cover glass, a photovoltaic cell-containing sealing layer having the photovoltaic cell and the sealing layer, and the back glass in that order. .
14. The photovoltaic module for paving according to claim 1 or 2, wherein the surface of the first side of the cover glass has a slip resistance value BPN of 30 or more.
15. The photovoltaic module for paving according to claim 1 or 2, wherein the photovoltaic cell includes a single crystal or polycrystalline silicon solar cell.
16. The photovoltaic module for paving according to claim 1 or 2, wherein the second surface of the cover glass does not include a layer made of a fired glass frit.
17. A solar power generation pavement block comprising the pavement photovoltaic module according to claim 1 or 2.
18. A method for manufacturing the paving photovoltaic module according to claim 1 or 2, comprising:
    a cover glass manufacturing step of manufacturing the cover glass including the particles protruding from the surface;
    A method for manufacturing a photovoltaic module for pavement, including a sealing step of sealing the photovoltaic cells included in the sealing layer using the cover glass.
19. having a first side and a second side;
    The first side includes particles protruding from the surface;
    A glass plate, wherein the particles have a particle size of 0.01 to 5 mm.
20. The glass plate includes a particle layer and a glass substrate, the particle layer is disposed on the first side, and the glass substrate is disposed on the second side,
    The particle layer includes the particles and a binder,
    The binder is a fired glass frit,
    20. The glass plate of claim 19, wherein the particles are bonded to the glass substrate using the binder.
21. The glass plate according to claim 19 or 20,
    An interlayer film for laminated glass,
    A laminated glass for a glass floor, comprising a glass substrate for laminated glass and a laminated glass substrate for laminated glass in that order,
    A laminated glass for a glass floor, wherein the interlayer film for laminated glass is disposed on the second side of the glass plate.

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