JP2013015612A - Method for manufacturing solar collection mirror, solar collection mirror, and solar thermal power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing solar collection mirrors capable of providing a high collection efficiency and massively manufacturing reflection surfaces of desired curvature, and to provide a solar collection mirror, and a solar thermal power generation system using the same.SOLUTION: A mold MD formed with a paraboloid of revolution on the lower surface is brought closer to a plasticity material from a film mirror FM side, to press and mold the plasticity material HL via the film mirror FM. The plasticity material is heated from the periphery with a not-shown heater while this state is maintained, and hardened to be formed into a support body HL. After having hardened the plasticity material, the mold MD is removed, then the film mirror FM pressed by the lower surface of the mold MD is formed on the paraboloid of revolution, and the shape is retained by the fixed support body HL, thus manufacturing the solar collection mirror SL.

Description

  The present invention relates to a method for manufacturing a solar light collecting mirror, a solar light collecting mirror, and a solar thermal power generation system using the same.

  In recent years, natural energy such as biomass energy, nuclear energy, wind energy, and solar energy has been studied as alternatives to fossil fuel energy such as oil and natural gas, but it is the most stable alternative energy for fossil fuel. In addition, the use of solar energy is considered promising as a large amount of natural energy. However, although solar energy is a very powerful alternative energy, from the viewpoint of utilizing it, (1) the energy density of solar energy is low, (2) it is difficult to store and transfer solar energy, etc. Is considered to be a problem.

  In response to the above-mentioned problem of solar energy, a method of solving the problem that the energy density of solar energy is low by collecting solar energy with a huge reflector has been proposed. As one of such solar thermal power generation systems, for example, a tower type solar thermal power generation system as described in Patent Document 1 is cited. This system has a plurality of reflecting mirrors arranged in a substantially circular shape or a substantially fan shape, and a tower installed in the center, and the sunlight is concentrated on the heat collecting part in the tower by the reflecting mirrors. Light is used to generate electricity using the heat.

  Here, in a solar thermal power generation system in which the distance from the reflecting mirror to the heat collecting part is as long as several tens of meters to several hundreds of meters, such as a tower type solar thermal power generation system, the light collection efficiency is still not sufficient. There is a need to improve the light collection efficiency. This will be described in detail below.

  Sun rays are not completely parallel light but rays having an inclination in an angle range corresponding to a viewing angle of 0.52 ° to 0.54 °. When the distance from the reflecting mirror to the heat collecting part is as short as several meters, the viewing angle of sunlight is almost negligible. However, when the distance from the reflecting mirror to the heat collecting part is long as in the tower type solar thermal power generation system, if the reflecting mirror is a plane mirror, the light ray of the component corresponding to the viewing angle out of the light rays reflected from the solar rays Since the light is diffused in proportion to the condensing distance, there is a problem that the reflected light cannot be completely received by the limited light receiving area of the heat collecting part, and the condensing efficiency is lowered.

  In order to solve the problem, a configuration in which a pseudo concave mirror is configured by combining a plurality of plane mirrors as described in FIG. 6 of Patent Document 1 is conceivable. However, in such a pseudo concave mirror, light is condensed. It was not enough from the viewpoint of efficiency.

  Further, in order to obtain a concave mirror made of a curved surface rather than a combination of planes, a complicated manufacturing process is required, and it is difficult to obtain the concave mirror easily and inexpensively. In particular, when a concave mirror is used in a tower type solar thermal power generation system, it is necessary to change the curvature of the concave surface according to the distance from the heat collecting part to the reflecting mirror. Is more difficult, and a solar power generation system having a plurality of concave mirrors having such various curvatures is necessarily expensive.

  Therefore, even in a solar thermal power generation system in which the distance from the reflecting mirror to the heat collecting part is as long as several tens of meters to several hundreds of meters, such as a tower type solar thermal power generation system, high light collection efficiency can be obtained. Therefore, there has been a demand for a solar light collecting mirror that can be easily and inexpensively manufactured, and that can easily obtain concave mirrors having various curvatures. On the other hand, even in the case of a reflector used in a trough type solar thermal power generation system in which the distance from the reflector to the heat collecting part is relatively short, some device is required to mass-produce the bent reflector with an optimal curvature.

JP 2009-218383 A

  The present invention has been made in view of the above problems, and the object thereof can be applied to any type such as a tower type solar thermal power generation system or a trough type solar thermal power generation system, and can obtain high light collection efficiency. In addition, it is an object of the present invention to provide a solar light collecting mirror manufacturing method, a solar light collecting mirror, and a solar thermal power generation system using the same.

The present invention according to claim 1 is a method of manufacturing a solar light collecting mirror,
Laying a deformable reflector on a plastic material;
Deforming the reflective portion and the plastic material;
And a step of fixing the shape of the plastic material.

  According to the present invention, the deformable reflective portion is laid on a plastic material, the reflective portion and the plastic material are deformed, and the shape of the plastic material is fixed in a simple process. The reflection part can be formed into a desired shape at low cost. In particular, when the reflective part is a film mirror, the film mirror surface is provided with irregularities in order to maintain the slipperiness when produced by roll-to-roll, and due to the irregularities resulting from the coating process, etc., compared to a normal glass mirror The flatness of the film mirror is often inferior. Therefore, since the film mirror has poor flatness, when used alone, there is a possibility that the light collection efficiency cannot be improved as compared with the glass mirror. However, by fixing the plastic material in a concave shape easily, Condensing efficiency can be greatly improved. In addition, it is because of the film mirror that the concave shape, particularly the rotationally symmetric concave shape can be easily made using a plastic material.

  The manufacturing method of the solar light collecting mirror according to claim 2 is the invention according to claim 1, wherein the reflecting portion is pressed by pressing a molding die against the plastic material via the reflecting portion. And the plastic material are deformed. Thereby, the mirror which has the reflection part of the same shape can be mass-produced. Also, by preparing a plurality of types of molds for molding, it is possible to easily mass-produce mirrors having concave reflecting portions having different curvatures.

  The method for manufacturing a solar light collecting mirror according to claim 3 is characterized in that, in the invention according to claim 2, the shape of the plastic material is fixed by curing the plastic material. . Thereby, it is suppressed that the shape of a mirror changes after installation, and stable efficiency can be exhibited over a long period of time.

  The method for manufacturing a solar light collecting mirror according to claim 4 is the invention according to claim 1, wherein the plastic material is disposed between the reflecting portion and the substrate, and the reflecting portion and the substrate are arranged. The reflecting portion and the plastic material are deformed by relatively approaching at least a part of the above. Thereby, since the condensing position of the mirror can be changed by a simple operation, the mirror adjustment operation when the reflected light is actually condensed on the heat collecting part using sunlight in the field becomes easy.

  The manufacturing method of the solar light collecting mirror according to claim 5 is the invention according to claim 4, wherein the reflection portion and the substrate are connected by a screw member, and the screw member is tightened. The reflective portion and the plastic material are deformed. In particular, the mirror adjustment work when the reflected light is actually collected on the heat collecting part using sunlight in the field becomes easy.

  The manufacturing method of the solar light collecting mirror according to claim 6 is the invention according to claim 5, wherein the distance between at least a part of the reflecting portion and the substrate is fixed using the screw member. The shape of the plastic material is fixed. Thereby, the change in the shape of the mirror after adjustment is suppressed, and stable efficiency can be exhibited over a long period of time.

  The solar light collecting mirror manufacturing method according to claim 7 is the invention according to claim 1, wherein the plastic material is a fluid contained in a container, and a part of the plastic material is used. By discharging to the outside of the container, the reflecting portion and the plastic material are deformed. Thereby, since the condensing position of the mirror can be changed by a simple operation, the mirror adjustment operation when the reflected light is actually condensed on the heat collecting part using sunlight in the field becomes easy.

  The solar light collecting mirror manufacturing method according to claim 8 is the invention according to claim 7, wherein the shape of the plastic material is fixed by sealing the plastic material in a container. Features. Thereby, the change in the shape of the mirror after adjustment is suppressed, and stable efficiency can be exhibited over a long period of time.

  The manufacturing method of the solar light collecting mirror according to claim 9 is characterized in that, in the invention according to any one of claims 1 to 8, the reflecting part after deformation has a paraboloid of revolution. The solar light collecting mirror manufactured by such a manufacturing method is preferably used for a solar thermal power generation system having a relatively long distance to the heat collecting section.

  The method for manufacturing a solar light collecting mirror according to claim 10 is characterized in that, in the invention according to any one of claims 1 to 8, the deformed reflecting portion has a bowl-shaped reflecting surface. . The solar light collecting mirror manufactured by such a manufacturing method is preferably used for a solar thermal power generation system having a relatively short distance to the heat collecting section.

  The solar light collecting mirror manufacturing method according to an eleventh aspect is characterized in that, in the invention according to any one of the first to tenth aspects, the reflecting portion is elastically deformable. This makes it possible to follow the deformation of the plastic material.

  According to a twelfth aspect of the present invention, the solar light collecting mirror includes a support made of a plastic material capable of fixing at least one surface in a predetermined shape, and a reflecting portion laid on the one surface.

  According to the present invention, by forming the reflection portion on one surface on which the plastic material can be fixed, the reflection portion can be formed into a desired shape at a low cost by a simple process.

  According to a thirteenth aspect of the present invention, in the invention according to the twelfth aspect, the solar light collecting mirror is captured by the capturing portion in a state where the capturing portion capturing the plastic material and the reflecting portion are laid. And changing means for changing the shape of the reflecting portion by moving or removing the plastic material. Thereby, the condensing position of mirror reflected light can be changed arbitrarily.

  The solar thermal power generation system according to claim 14 has at least one heat collecting part and the solar light collecting mirror according to claim 13, wherein the solar light collecting mirror reflects sunlight. And irradiating the heat collecting part.

  Here, the “reflecting part” is a member that can reflect sunlight and is preferably thinner than a plastic material and elastically deformable. However, the reflection part itself may be a plastic member that can be plastically deformed. A thick glass mirror, a thin glass mirror, a film mirror, etc. are mentioned as an example of a reflection part. In the case of a glass mirror having a thick reflecting portion, the glass is preferably deformable. The reflective portion is laid on a plastic material. “Laying” includes providing the reflecting portion directly on the plastic material and providing it indirectly with another member interposed therebetween. One reflection part may be sufficient and it may be divided | segmented into several sheets. Furthermore, a shape such as a circle, an ellipse, a quadrangle such as a square or a rectangle, or a regular hexagon is preferable. The central portion of the reflecting portion is preferably near the center in the case of a circle, near the intersection of diagonal lines in the case of a square shape, and near the intersection of diagonal lines in the case of a regular hexagon.

  “Film mirror” refers to a film-like mirror in which a reflective layer is provided on a film-like resin substrate. The thickness of the film is 50 to 400 μm, preferably 70 to 250 μm, and particularly preferably 100 to 220 μm. It is preferable to set the thickness to 50 μm or more because when the film mirror is attached to the structure, it is easy to obtain good regular reflectance without bending the mirror. Moreover, since it becomes easy to handle by making it 400 micrometers or less, it is preferable.

  The thickness from the surface of the film mirror to the reflective layer is preferably 0.2 mm or less as the reflective part of the solar light collecting mirror used in the tower type solar power generation system. The reason will be described in detail below.

  In a system having a long distance from the reflecting portion to the heat collecting portion such as a tower type solar power generation system, the incident angle of sunlight incident on the film mirror may increase in the morning or evening. (For example, 45 degrees or more) In such a case, as shown in FIG. 8B, a surface layer (a layer between the surface of the film mirror and the reflective layer. One layer may be used, or a plurality of layers may be combined with the surface layer. If it is thick, the following problems occur. When dust or sand 100 adheres to the surface of the film mirror, the light B incident on the dust or sand 100 part naturally does not reach the reflective layer 102 and is not reflected or scattered, contributing to the light collection efficiency. do not do. In addition, the light A that is incident on a portion where there is no dust or sand 100 is transmitted through the surface layer 101 and reflected by the reflective layer 102. However, since the incident angle is large, the reflected light is reflected by dust or sand. There is a problem that it is blocked at 100 and does not contribute to the light collection efficiency. On the other hand, when the surface layer is thinned to 0.2 mm or less as shown in FIG. 8A, only the light B ′ incident on the dust or sand 100 part contributes to the reduction of the light collection efficiency. It can prevent that the light reflected by the reflection layer like A in FIG.8 (b) contributes to the fall of condensing efficiency. Therefore, it is preferable because a decrease in light collection efficiency when dust or sand adheres can be suppressed. That is, by making the surface layer of the film mirror as thin as 0.2 mm or less, when dust or sand adheres to the surface, even if the incident angle is large, the problem of reflected light such as light A does not occur, This is preferable because it is possible to prevent a decrease in light collection efficiency. In addition, it is preferable that the thickness of the surface layer is 0.2 mm or less. This is not limited to the film mirror, and the thickness of the surface layer is 0.2 mm or less also in other reflective portions such as a thin glass mirror. It is preferable for the same reason as described above. Hereinafter, the film mirror will be specifically described.

  An example of a film mirror is shown in FIG. In the example shown in FIG. 1, the film mirror E has a polymer film layer 1, a gas barrier layer 2 made of metal oxide, a reflective layer (Ag layer) 3 made of metal, and an adhesive layer 4 in order from the sunlight side. It becomes. A release film 5 can be attached to the lower surface of the adhesive layer 4, and the release film 5 can be appropriately peeled off when desired to adhere to a metal plate, resin plate or laminated plate as a structure.

  The film mirror is not limited to the configuration shown in FIG. 1, and various functional layers may be further added, or conversely, the gas barrier layer and the like may be removed from the example of FIG. Moreover, even if it is the said structure, functionality can be provided to each layer. Below, the aspect of another film mirror which added various functional layers is demonstrated. However, the film mirror that can be used in the present invention is not limited to these embodiments. In the following description, “upper” means the side on which sunlight is incident, and “lower” means the opposite side.

  For example, in FIG. 1, an ultraviolet absorber is added to the polymer film layer 1, the underlying gas barrier layer 2 functions as a water vapor barrier layer, and the underlying reflective layer 3 is composed of a silver vapor deposition layer. It is good also as a film mirror which has the structure which laminated | stacked the adhesion layer 4 and the peeling film 5 under the layer. The durability increases by adding an ultraviolet absorber to the polymer film layer.

  The film mirror may be a film mirror in which a corrosion inhibitor layer (a polymer layer containing a corrosion inhibitor) is provided between the reflective layer 3 and the adhesive layer 4. By adding a corrosion inhibitor layer, it is possible to prevent deterioration of the film mirror with respect to oxygen, hydrogen sulfide gas (sulfide ions) and salt, and provide a smooth optical surface for a long period of time.

  In the film mirror, an adhesive layer and a corrosion inhibitor layer are laminated in order from the side where sunlight enters between the gas barrier layer 2 and the reflective layer 3, and a polymer is interposed between the reflective layer 3 and the adhesive layer 4. It is good also as a film mirror which provided the film layer.

  The film mirror may be a film mirror in which a hard coat layer and a polymer film layer are laminated in order from the sunlight incident side instead of the polymer film layer 1 to which an ultraviolet absorber is added. The hard coat layer preferably contains an ultraviolet absorber or the like.

  The film mirror may be a film mirror in which an ultraviolet reflecting layer is provided on the polymer film layer instead of the hard coat layer.

  The film mirror may be a film mirror provided with a sacrificial anticorrosive layer instead of the corrosion inhibitor layer.

  Next, each layer of the film mirror and materials used for each layer will be described.

(Polymer film layer)
The film material of the polymer film layer preferably contains, for example, polyester, polyethylene terephthalate, polyethylene naphthalate, acrylic, polycarbonate, polyolefin, cellulose, or polyamide from the viewpoint of flexibility and weight reduction. Among these, an acrylic copolymer excellent in weather resistance and particularly copolymerized with at least two kinds of acrylic monomers is preferable.

  Specific examples of suitable acrylic copolymers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, and butyl methacrylate. One or more monomers selected from monomers having no functional group in the side chain such as alkyl (meth) acrylate such as cyclohexyl methacrylate and 2-ethylhexyl methacrylate (hereinafter referred to as non-functional monomers) 1 or 2 or more types selected from monomers such as 2-hydroxyethyl methacrylate, glycidyl methacrylate, acrylic acid, methacrylic acid, itaconic acid, etc. -A combination of one or more monomers having a functional group such as OH or COOH in the side chain (hereinafter referred to as a functional monomer), solution polymerization, suspension polymerization, emulsion polymerization, bulk Examples thereof include acrylic copolymers having a weight average molecular weight of 40,000 to 1,000,000, preferably 100,000 to 400,000, obtained by copolymerization by a polymerization method such as a polymerization method. Among them, ethyl acrylate, methyl acrylate, 50 to 90% by weight of a non-functional monomer that gives a relatively low Tg polymer such as ethylhexyl methacrylate, and 10 to 50 a non-functional monomer that gives a relatively high Tg polymer such as methyl methacrylate, isobutyl methacrylate, cyclohexyl methacrylate, etc. Mass%, 2-hydroxyethyl methacrylate, acrylic acid, itaconic acid Acrylic polymers such as those containing the functional monomer 0 to 10% by weight is most preferred.

  The shape of a film should just be a shape calculated | required as a surface coating material of various film mirrors, such as a plane, a diffusion surface, a concave surface, a convex surface, and a trapezoid.

  The thickness of the polymer film layer is preferably 10 to 125 μm. If it is thinner than 10 μm, the tensile strength and tear strength tend to be weak, and if it is thicker than 125 μm, the average reflectance in the range of 1600 nm to 2500 nm is less than 80%.

  The surface of the polymer film layer may be subjected to corona discharge treatment, plasma treatment or the like in order to improve adhesion with a metal oxide layer, a hard coat layer, a dielectric coating layer, or the like.

  The polymer film layer preferably contains any one of benzotriazole-based, benzophenone-based, triazine-based, cyanoacrylate-based, and polymer-type ultraviolet absorbers.

(UV absorber)
As the ultraviolet absorber used for the polymer film layer, an ultraviolet absorbent having a wavelength of 370 nm or less and excellent absorption of ultraviolet rays and having a small absorption of visible light having a wavelength of 400 nm or more is preferable from the viewpoint of utilization of sunlight.

  Examples of ultraviolet absorbers include oxybenzophenone compounds, benzotriazole compounds, salicylic acid ester compounds, benzophenone compounds, cyanoacrylate compounds, nickel complex salts compounds, triazine compounds, and the like. Compounds, benzotriazole-based compounds and triazine-based compounds with little coloring are preferred. Further, ultraviolet absorbers described in JP-A Nos. 10-182621 and 8-337574, and polymer ultraviolet absorbers described in JP-A Nos. 6-148430 and 2003-113317 may be used.

  Specific examples of the benzotriazole ultraviolet absorber include 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) benzo Triazole, 2- (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5 Chlorobenzotriazole, 2- (2′-hydroxy-3 ′-(3 ″, 4 ″, 5 ″, 6 ″ -tetrahydrophthalimidomethyl) -5′-methylphenyl) benzotriazole, 2,2-methylenebis (4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol), 2- (2′-hydroxy- '-Tert-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-(2-octyloxycarbonylethyl) -phenyl) -5 -Chlorobenzotriazole, 2- (2'-hydroxy-3 '-(1-methyl-1-phenylethyl) -5'-(1,1,3,3-tetramethylbutyl) -phenyl) benzotriazole, 2 -(2H-benzotriazol-2-yl) -6- (linear and side chain dodecyl) -4-methylphenol, octyl-3- [3-tert-butyl-4-hydroxy-5- (chloro-2H- Benzotriazol-2-yl) phenyl] propionate and 2-ethylhexyl-3- [3-tert-butyl-4-hydroxy-5- (5-chloro-2) - can be exemplified mixtures of benzotriazol-2-yl) phenyl] propionate, and the like.

  Moreover, as a commercial item, TINUVIN 171, TINUVIN 900, TINUVIN 928, TINUVIN 360 (all are manufactured by Ciba Japan), LA31 (made by ADEKA), RUVA-100 ( Otsuka Chemical).

  Specific examples of the benzophenone compounds include 2,4-dihydroxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfobenzophenone, bis (2-methoxy-4-hydroxy- 5-benzoylphenylmethane) and the like, but are not limited thereto.

(Gas barrier layer made of metal oxide)
Examples of the gas barrier layer made of a metal oxide include silicon oxide, aluminum oxide, or a composite oxide starting from silicon oxide and aluminum oxide, zinc oxide, tin oxide, indium oxide, niobium oxide, chromium oxide, and the like. From the viewpoint of water vapor barrier properties, silicon oxide, aluminum oxide, or a composite oxide starting from silicon and aluminum is preferable. In addition, a multilayer film in which a low refractive index layer having a refractive index of 1.35 to 1.8 at a wavelength of 550 nm and a high refractive index film having a refractive index of 1.85 to 2.8 at a wavelength of 550 nm are alternately laminated. Also good. Examples of the low refractive index film material include silicon oxide, aluminum oxide, silicon nitride, and aluminum nitride. Examples of the high refractive index film material include niobium oxide, titanium oxide, zinc oxide, tin oxide, indium oxide, tantalum oxide, and zirconium oxide. These are formed by a vacuum process such as a vacuum deposition method, a sputtering method, a PVD method (physical vapor deposition method) such as ion plating, or a CVD method (chemical vapor deposition method). The thickness of the gas barrier layer made of metal oxide is preferably in the range of 5 to 800 nm, more preferably in the range of 10 to 300 nm.

  A silicon oxide layer or an aluminum oxide layer thus obtained by producing a gas barrier layer on a polymer film, or a composite oxide layer using silicon oxide and aluminum oxide as a starting material is oxygen, carbon dioxide, air, etc. Excellent barrier action against gas or water vapor.

A laminate of a silicon oxide layer or an aluminum oxide layer, or a composite oxide layer starting from silicon oxide or aluminum oxide and a polymer film has a water vapor permeability of 1 × 10 ^{−2 at} 40 ° C. and 90% RH. It is preferable that it is below g / m < ² > * 24h. The water vapor transmission rate can be measured with a water vapor transmission rate measuring device PERMATRAN-W3-33 manufactured by MOCON.

  Further, the silicon oxide layer or the aluminum oxide layer, or the composite oxide layer using silicon oxide and aluminum oxide as a starting material has a thickness of 1 μm or less, and the average value of each light transmittance is 90% or more. It is preferable. Thereby, there is no light loss and sunlight can be reflected efficiently.

(Ratio of thickness of gas barrier layer consisting of polymer film layer and metal oxide)
The ratio of the thickness of the gas barrier layer made of the polymer film layer and the metal oxide is preferably in the range of 0.1% to 5%. When the ratio is larger than 0.1%, that is, when the thickness of the gas barrier layer with respect to the polymer film is increased, it is preferable because sufficient gas barrier properties can be obtained and the function of suppressing the progress of deterioration is exhibited. When the ratio is less than 5%, that is, when the thickness of the gas barrier layer with respect to the polymer film becomes thin, even when an external bending force is applied, the metal oxide is hard to crack, resulting in gas barrier properties and progress of deterioration. This is preferable because the function of suppressing the above is exhibited.

(Reflective layer made of metal)
As the reflective layer made of metal, for example, silver or a silver alloy, gold, copper, aluminum, or an alloy thereof can be used. In particular, it is preferable to use silver. Such a reflective layer serves as a reflective film that reflects light. By making the reflective layer a film made of silver or a silver alloy, the reflectance of the film mirror from the infrared region to the visible light region can be increased, and the dependency of the reflectance on the incident angle can be reduced. From the infrared region to the visible light region means a wavelength region of 2500 to 400 nm. The incident angle means an angle with respect to a line (normal line) perpendicular to the film surface.

  The silver alloy is composed of silver and one or more other metals selected from the group consisting of gold, palladium, tin, gallium, indium, copper, titanium, and bismuth from the viewpoint of improving the durability of the reflective layer. Alloys are preferred. As the other metal, gold is particularly preferable from the viewpoint of high temperature humidity resistance and reflectance.

  When the reflective layer is a film made of a silver alloy, 90 to 99.8 atomic percent of silver is preferable in the total (100 atomic percent) of silver and other metals in the reflective layer. Further, the other metal is preferably 0.2 to 10 atomic% from the viewpoint of durability.

  The thickness of the reflective layer is preferably 60 to 300 nm, particularly preferably 80 to 200 nm. When the thickness of the reflective layer is larger than 60 nm, it is preferable because the film thickness is sufficient, light is not transmitted, and the reflectance in the visible light region of the film mirror can be sufficiently secured. The reflectance increases in proportion to the film thickness up to about 200 nm, but it does not depend on the film thickness above 200 nm. Rather, it is preferable that the thickness of the reflective layer is less than 300 nm, because the surface of the reflective layer is less likely to be uneven, and light scattering is less likely to occur, so that the reflectance in the visible light region does not decrease.

  The film mirror is required to be glossy, but the method of producing and bonding a metal foil loses gloss because of surface irregularities. For film mirrors that require uniform surface roughness over a wide area, metal foil lamination is not preferred as a manufacturing method. The reflective layer made of metal is preferably formed by wet plating or dry plating such as vacuum deposition. Or you may make it apply | coat the coating liquid containing a silver complex compound, reduce | regenerate by baking or a reducing agent, generate | occur | produce silver, and form a reflective layer.

(Adhesive layer)
The adhesive layer is not particularly limited, and for example, any of a dry laminating agent, a wet laminating agent, a heat sealing agent, a hot melt agent, and the like is used. For example, polyester resin, urethane resin, polyvinyl acetate resin, acrylic resin, nitrile rubber, etc. are used. The laminating method is not particularly limited, and for example, it is preferable to carry out continuously by a roll method from the viewpoint of economy and productivity. The thickness of the adhesive layer is usually selected from a range of about 1 to 50 μm. When the thickness is larger than 1 μm, a sufficient adhesive effect can be obtained. On the other hand, when the thickness is less than 50 μm, the pressure-sensitive adhesive layer is not too thick and the drying rate is not slowed, which is efficient. In addition, the original adhesive strength can be obtained, and no adverse effects such as residual solvent can occur.

(Peeling film)
The release film preferably has a base material and a release agent layer provided on the base material.

  The release film has high smoothness on the outer surface. Examples of the release agent constituting the release film include silicone resins, long-chain alkyl resins, fluorine resins, fluorosilicone resins, long-chain alkyl-modified alkyd resins, silicone-modified alkyd resins, and the like. .

  Among the above, when a silicone resin is used as a material for the release agent, more excellent release properties are exhibited. As the silicone resin, any of addition type, condensation type, solventless type and the like can be used.

  The average thickness of the release agent constituting the release film is not particularly limited, but is preferably 0.01 to 0.3 μm, and more preferably 0.05 to 0.2 μm. When the average thickness of the release agent layer is larger than the lower limit, the function as the release agent layer can be sufficiently exhibited. On the other hand, when the average thickness of the release agent layer is smaller than the above upper limit value, it is preferable that when the release film is wound into a roll, blocking does not easily occur and no trouble occurs in feeding.

(Corrosion inhibitor layer)
The corrosion inhibitor layer functions to prevent discoloration of a reflective layer made of metal (specifically, an Ag layer), such as thioether, thiol, Ni organic compound, benzotriazole, imidazole, oxazole, tetra Examples include Zaindene, pyrimidine, and thiadiazole.

  The corrosion inhibitor layer is roughly classified into a corrosion inhibitor having an adsorption group with silver and an antioxidant. Specific examples of these corrosion inhibitors and antioxidants are given below.

<< Corrosion inhibitor with adsorption group with silver >>
Corrosion inhibitors having an adsorption group with silver include amines and derivatives thereof, products having a pyrrole ring, products having a triazole ring, products having a pyrazole ring, products having a thiazole ring, products having an imidazole ring, indazole It is desirable to be selected from a ring-containing product, a copper chelate compound, a thiourea, a product having a mercapto group, at least one naphthalene-based compound, or a mixture thereof.

  Examples of amines and derivatives thereof include ethylamine, laurylamine, tri-n-butylamine, o-toluidine, diphenylamine, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, monoethanolamine, diethanolamine, triethanolamine, 2N- Dimethylethanolamine, 2-amino-2-methyl-1,3-propanediol, acetamide, acrylamide, benzamide, p-ethoxychrysidine, dicyclohexylammonium nitrite, dicyclohexylammonium salicylate, monoethanolaminebenzoate, dicyclohexylammonium benzoate, diisopropyl Ammonium benzoate, diisopropylammonium nitrite Cyclohexylamine carbamate, nitronaphthalene nitrite, cyclohexylamine benzoate, dicyclohexylammonium cyclohexanecarboxylate, cyclohexylamine cyclohexane carboxylate, dicyclohexylammonium acrylate, cyclohexylamine acrylate, or mixtures thereof.

  Examples of the compound having a pyrrole ring include N-butyl-2,5-dimethylpyrrole, N-phenyl-2,5dimethylpyrrole, N-phenyl-3-formyl-2,5-dimethylpyrrole, N-phenyl-3, 4-diformyl-2,5-dimethylpyrrole, etc., or a mixture thereof.

  Examples of the compound having a triazole ring include 1,2,3-triazole, 1,2,4-triazole, 3-mercapto-1,2,4-triazole, 3-hydroxy-1,2,4-triazole, 3- Methyl-1,2,4-triazole, 1-methyl-1,2,4-triazole, 1-methyl-3-mercapto-1,2,4-triazole, 4-methyl-1,2,3-triazole, Benzotriazole, tolyltriazole, 1-hydroxybenzotriazole, 4,5,6,7-tetrahydrotriazole, 3-amino-1,2,4-triazole, 3-amino-5-methyl-1,2,4- Triazole, carboxybenzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-5) -Tert-butylphenyl) benzotriazole, 2- (2'-hydroxy3'5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-4-octoxyphenyl) benzotriazole, or the like, or These mixtures are mentioned.

  Examples of the compound having a pyrazole ring include pyrazole, pyrazoline, pyrazolone, pyrazolidine, pyrazolidone, 3,5-dimethylpyrazole, 3-methyl-5-hydroxypyrazole, 4-aminopyrazole, and the like, or a mixture thereof.

  Examples of the compound having a thiazole ring include thiazole, thiazoline, thiazolone, thiazolidine, thiazolidone, isothiazole, benzothiazole, 2-N, N-diethylthiobenzothiazole, P-dimethylaminobenzallodanine, 2-mercaptobenzothiazole, etc. Or a mixture thereof.

  Examples of the compound having an imidazole ring include imidazole, histidine, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-undecylimidazole, 1-benzyl-2-methyl. Imidazole, 2-phenyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecyl Imidazole, 2-phenyl-4-methyl-5-hydromethylimidazole, 2-phenyl-4,5 dihydroxymethylimidazole, 4-formylimidazole, 2-methyl-4-formylimidazole, 2-phenyl-4-form Ruimidazole, 4-methyl-5-formylimidazole, 2-ethyl-4-methyl-5-formylimidazole, 2-phenyl-4-methyl-4-formylimidazole, 2-mercaptobenzimidazole, etc., or these Of the mixture.

  Examples of the substance having an indazole ring include 4-chloroindazole, 4-nitroindazole, 5-nitroindazole, 4-chloro-5-nitroindazole, and a mixture thereof.

  Examples of the copper chelate compounds include acetylacetone copper, ethylenediamine copper, phthalocyanine copper, ethylenediaminetetraacetate copper, hydroxyquinoline copper, and a mixture thereof.

  Examples of thioureas include thiourea, guanylthiourea, and the like, or a mixture thereof.

  As a product having a mercapto group, if the above-mentioned materials are added, mercaptoacetic acid, thiophenol, 1,2-ethanediol, 3-mercapto-1,2,4-triazole, 1-methyl-3-mercapto -1,2,4-triazole, 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, glycol dimercaptoacetate, 3-mercaptopropyltrimethoxysilane, and the like, or a mixture thereof.

  Examples of the naphthalene type include thionalide.

"Antioxidant"
As the antioxidant that can be used in the corrosion inhibitor layer according to the present invention, it is preferable to use a phenol-based antioxidant, a thiol-based antioxidant, and a phosphite-based antioxidant. Examples of phenolic antioxidants include 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 2,2′-methylenebis (4-ethyl-6-t-). Butylphenol), tetrakis- [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, 2,6-di-t-butyl-p-cresol, 4,4 '-Thiobis (3-methyl-6-tert-butylphenol), 4,4'-butylidenebis (3-methyl-6-tert-butylphenol), 1,3,5-tris (3', 5'-di-t -Butyl-4'-hydroxybenzyl) -S-triazine-2,4,6- (1H, 3H, 5H) trione, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate ,bird Tylene glycol bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate], 3,9-bis [1,1-di-methyl-2- [β- (3-t-butyl) -4-hydroxy-5-methylphenyl) propionyloxy] ethyl] -2,4,8,10-tetraoxoxaspiro [5,5] undecane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene and the like.

  In particular, the phenolic antioxidant preferably has a molecular weight of 550 or more. Examples of the thiol antioxidant include distearyl-3,3′-thiodipropionate, pentaerythritol-tetrakis- (β-lauryl-thiopropionate), and the like. Examples of the phosphite antioxidant include tris (2,4-di-t-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, di (2,6-di-t-butylphenyl) pentaerythritol. Diphosphite, bis- (2,6-di-t-butyl-4-methylphenyl) -pentaerythritol diphosphite, tetrakis (2,4-di-t-butylphenyl) 4,4′-biphenylene-diphosphonite 2,2′-methylenebis (4,6-di-t-butylphenyl) octyl phosphite and the like.

  As an example of the manufacturing method of a film mirror, the example which forms the reflection layer which consists of metals on the surface on a polymer film layer, and also laminate | stacks a corrosion inhibitor layer on it is mentioned. After laminating the adhesive layer and the release film on the lower surface of the polymer film layer, an adhesive layer can be formed on the surface of the polymer film layer, that is, on the corrosion inhibitor layer. A gas barrier layer may be formed on the surface under another polymer film layer, and the gas barrier layer of another polymer film layer and the adhesive layer of the polymer film layer may be faced to each other and manufactured. .

(Adhesive layer)
As an adhesive layer, it consists of resin and adheres a film and the above-mentioned polymer film layer containing a ultraviolet absorber. Therefore, the adhesive layer needs to have a closeness and transparency in order to bring out the high reflection performance inherently possessed by the reflective layer made of a metal, and the adhesiveness for closely adhering the film and the ultraviolet absorber-containing polymer film layer.

  The resin used for the adhesive layer is not particularly limited as long as it satisfies the above conditions of adhesion, heat resistance, and smoothness. Polyester resin, acrylic resin, melamine resin, epoxy resin, polyamide Resin, vinyl chloride resin, vinyl chloride vinyl acetate copolymer resin or the like, or a mixed resin thereof can be used. From the viewpoint of weather resistance, a polyester resin and a melamine resin mixed resin are preferable. It is more preferable to use a thermosetting resin mixed with a curing agent.

  The thickness of the adhesive layer is preferably 0.01 to 3 μm, more preferably 0.1 to 1 μm. If the thickness is less than 0.01 μm, the adhesiveness is deteriorated and there is no effect of forming an adhesive layer, and it is difficult to cover the unevenness on the surface of the film substrate, and the smoothness is deteriorated. Even if the thickness is greater than 3 μm, improvement in adhesion cannot be expected, and on the contrary, unevenness of coating may cause poor smoothness or insufficient curing of the adhesive layer, which is not preferable.

  As a method for forming the adhesive layer, conventionally known coating methods such as a gravure coating method, a reverse coating method, and a die coating method can be used.

(Hard coat layer)
A hard coat layer can be provided as the outermost layer of the film mirror. The hard coat layer is provided for preventing scratches.

  The hard coat layer can be composed of an acrylic resin, a urethane resin, a melamine resin, an epoxy resin, an organic silicate compound, a silicone resin, or the like. In particular, silicone resins and acrylic resins are preferable in terms of hardness and durability. Further, in terms of curability, flexibility, and productivity, those made of an active energy ray-curable acrylic resin or a thermosetting acrylic resin are preferable.

  The active energy ray-curable acrylic resin or thermosetting acrylic resin is a composition containing a polyfunctional acrylate, an acrylic oligomer, or a reactive diluent as a polymerization curing component. In addition, you may use what contains a photoinitiator, a photosensitizer, a thermal-polymerization initiator, a modifier, etc. as needed.

  Acrylic oligomers include polyester acrylates, urethane acrylates, epoxy acrylates, polyether acrylates, etc., including those in which a reactive acrylic group is bonded to an acrylic resin skeleton, and rigid materials such as melamine and isocyanuric acid. A structure in which an acrylic group is bonded to a simple skeleton can also be used.

  In addition, the reactive diluent has a function of a solvent in the coating process as a medium of the coating agent, and has a group that itself reacts with a monofunctional or polyfunctional acrylic oligomer. It becomes a copolymerization component.

  Commercially available polyfunctional acrylic cured paints include Mitsubishi Rayon Co., Ltd. (trade name “Diabeam (registered trademark)” series, etc.), Nagase Sangyo Co., Ltd. (trade name “Denacol (registered trademark)” series, etc. ), Shin-Nakamura Co., Ltd. (trade name “NK Ester” series, etc.), Dainippon Ink and Chemicals Co., Ltd .; (trade name “UNIDIC (registered trademark)” series, etc.), Toa Gosei Chemical Industry Co., Ltd. (trade name) ("Aronix (registered trademark)" series, etc.), Nippon Oil & Fats Co., Ltd. (trade name "Blemmer (registered trademark)" series, etc.), Nippon Kayaku Co., Ltd. (trade name, "KAYARAD (registered trademark)" series, etc.), Products such as Kyoeisha Chemical Co., Ltd. (trade names “light ester” series, “light acrylate” series, etc.) can be used.

  In the hard coat layer, various additives can be further blended as necessary. For example, stabilizers such as antioxidants, light stabilizers, ultraviolet absorbers, surfactants, leveling agents, antistatic agents, and the like can be used.

  The leveling agent is effective in reducing surface irregularities, particularly when the functional layer is applied. As a leveling agent, for example, a dimethylpolysiloxane-polyoxyalkylene copolymer (for example, SH190 manufactured by Toray Dow Corning Co., Ltd.) is suitable as a silicone leveling agent.

(Ultraviolet reflection layer)
An ultraviolet reflection layer may be provided on the film mirror. The ultraviolet reflection layer is a layer that reflects ultraviolet light and transmits visible light and infrared light. The ultraviolet reflection layer preferably has an average reflectance of 75% or more for electromagnetic waves (ultraviolet rays) of 300 nm to 400 nm. The ultraviolet reflective layer preferably has an average transmittance of 80% or more with respect to electromagnetic waves (visible light and infrared light) of 400 nm to 2500 nm.

  Since the film mirror has a polymer film layer on the side of the metal reflective layer where sunlight is incident and the sunlight that has passed through the polymer film layer is reflected by the metal reflective layer, the polymer film layer always reflects sunlight. Be exposed. Therefore, by disposing the ultraviolet reflective layer on the side of the polymer film layer on which sunlight is incident, the polymer film layer can be prevented from being deteriorated and discolored by ultraviolet rays, and the decrease in light transmittance of the polymer film layer can be reduced. Therefore, it becomes possible to reduce the reflectance drop of the film mirror. Further, by providing the ultraviolet reflecting layer on the side of the polymer film layer on which sunlight is incident, it is possible to reduce a decrease in moisture resistance of the polymer film layer due to deterioration of the polymer film layer due to ultraviolet rays of sunlight. Therefore, it is possible to prevent the metal reflective layer from being deteriorated due to the deterioration of the moisture resistance of the polymer film layer, so that it is possible to reduce the reflectance drop of the film mirror.

  Although it does not specifically limit as an ultraviolet reflective layer, The dielectric multilayer film which consists of an alternating layer of 2 or more types of dielectric materials from which a refractive index differs can be used. The dielectric multilayer film according to the present invention is preferably configured by alternately stacking a high refractive index dielectric layer and a low refractive index dielectric layer in an amount of 2 to 6 layers alternately. Thus, the scratch resistance of a dielectric multilayer film can be improved by using a multilayer structure in which dielectric layers are stacked. The high refractive index dielectric layer preferably has a refractive index of 2.0 to 2.6. Further, the low refractive index dielectric layer preferably has a refractive index of 1.8 or less.

The dielectric layer of high refractive index can be preferably used SiO _2, Al ₂ O ₃ as a dielectric layer of ZrO _2, TiO ₂ the low refractive index. TiO ₂ can be used more preferably as the high refractive index dielectric layer used in the present invention, and SiO ₂ can be used more preferably as the low refractive index dielectric layer. When TiO ₂ is used on the outermost surface of the ultraviolet reflecting layer, that is, the outermost surface of the film mirror, as a dielectric material having a high refractive index, the anti-staining effect on the mirror surface due to the photocatalytic effect of TiO ₂ can be obtained. It is possible to reduce the decrease in the reflectance of the film mirror caused by the above.

(Sacrificial protection layer)
The film mirror may have a sacrificial anticorrosive layer. The sacrificial anticorrosive layer is a layer that protects the metal reflective layer by sacrificial anticorrosion, and disposing the sacrificial anticorrosive layer between the metal reflective layer and the protective layer can improve the corrosion resistance of the metal reflective layer. it can. As the sacrificial anticorrosive layer, copper having a higher ionization tendency than silver is preferable. By providing the sacrificial anticorrosive layer of copper under the reflective layer made of silver, deterioration of silver can be suppressed.

  A film mirror can be manufactured by the following processes, for example.

[Step 1]
A biaxially stretched polyester film (polyethylene terephthalate film, thickness 60 μm) is prepared as a polymer film layer (base material), placed inside the vapor deposition machine, and the inside of the vapor deposition machine is evacuated by a vacuum pump. In the vacuum deposition machine, there are arranged a feeding device for feeding out a polymer film wound in a roll shape, and a winding device for taking up the polymer film deposited on the polymer film by vapor deposition. A large number of rolls are arranged between the feeding device and the winding device so as to respectively guide the film, and are driven to rotate in synchronization with the polymer film travel by the driving means.

[Step 2]
A metal oxide deposition nucleus evaporation source is disposed at a position facing the upstream portion in the running direction of the polymer film layer. The deposition nuclear evaporation source is for depositing metals such as Si, Al, Ag, Cu, etc. on polymer films. Metal vapor is generated by vacuum deposition or the like, and the metal is uniformly distributed over the entire width of the film. An oxide vapor deposition film and a metal vapor deposition film are formed.

[Step 3]
A polyester-based adhesive is applied to the surface of the metal vapor deposition film produced in step 2 to a thickness of 5 μm. Not only the above-mentioned production order but also a corrosion inhibitor effective for preventing metal deterioration after step 2 may be applied, and a sacrificial anticorrosive layer, for example, Cu may also be deposited to prevent metal deterioration.

  In addition, in order to protect the polymer film from strong ultraviolet rays, if an ultraviolet absorber is added to the polymer film and other hard coat layers arranged on the side where sunlight is incident, coloring is prevented and reflection efficiency is maintained. be able to.

  The above is an explanation of the “film mirror”.

  Next, the “thin glass mirror” refers to a mirror in which a reflective layer is provided on a thin glass substrate. The thickness of the glass is preferably 25 to 1500 μm. The thin glass mirror can be directly attached to the substrate without providing a structure, but may be attached to the substrate after being fixed to the structure.

  “Plastic material” is preferably a flexible deformable solid, a gel-like solid, or a liquid or gas contained in a deformable container, and has at least one shape before fixing. It can be fixed. The plastic material may be solidified after being deformed and fixed. Also, when the plastic material is liquid or gas, the amount of liquid or gas is changed in the state of being accommodated in the container, and the surrounding container (with the reflective part laid) is deformed accordingly, and a certain amount By sealing at the point, the plastic material may be deformed and fixed without changing the properties of the plastic material. The plastic material may be a plastically deformable material. A support is obtained by fixing the plastic material after deformation. Examples of the plastic material include gypsum, UV curable resin (for example, trade names 3161, 3164, 3165 manufactured by ThreeBond), thermosetting resin (for example, phenol resin, epoxy resin, silicon resin, urea resin, melamine resin), and various liquids. Etc. Fixing of the plastic material includes UV curing, curing with visible light, thermal curing, sealing, and the like. The plastic material is preferably molded before fixing. Molding can be performed by methods such as embossing, screwing, and negative pressure. The formed surface is preferably a paraboloid shape (three-dimensional concave surface) or a cylindrical shape (two-dimensional concave surface). The concave surface is preferably rotationally symmetric. The reflecting portion is preferably provided on one surface to be fixed. Since one surface lays a reflection part, it is preferable that the surface is a flat surface.

  A capturing portion that captures the plastic material may be provided. As the capturing part, there are a plate-like case for supporting a gel-like solid and a case for supporting a liquid or gas. As the shape of the capturing part, the shape viewed from the direction orthogonal to the surface of the capturing part is preferably a circular shape, an elliptical shape, a square shape such as a square or a rectangle, or a regular hexagonal shape. The plate-shaped capturing portion may be a single plate shape, or may be a shape in which a plurality of plates of different materials are laminated, and the inside of the plate has a honeycomb structure or a lattice shape for weight reduction. A shape having a frame and having a surface covered with a thin plate may be used. As a material of the capturing part, titanium, iron, steel, SUS, FRP, copper, brass or bronze, aluminum, glass, or the like can be used alone or as a composite material. When used as a composite material, these materials are preferably used as a plate material so that a hollow structure such as a honeycomb structure is sandwiched between them, thereby promoting weight reduction. The honeycomb structure can be formed by processing aluminum, resin, paper or the like. More specific examples of the trapping part include a honeycomb structure sandwiched between two aluminum alloy plates, a foam layer sandwiched between two aluminum alloy plates, and a honeycomb structure sandwiched between two FRP boards And those having a honeycomb structure sandwiched between an aluminum alloy plate and an FRP board, and those having a honeycomb structure sandwiched between SUS plates.

  The space in which the plastic material is accommodated may be either not sealed or sealed. When the plastic material is not hermetically sealed, the reflective part and the plastic material can be deformed by placing a gel-like solid between the reflective part and the substrate and pressing from the reflective part side. At this time, as a member to be pressed, there are a mold, a screw member that penetrates a plastic material from the reflection portion and reaches the substrate.

  When the plastic material is hermetically sealed, the plastic material is accommodated in a deformable sealed container (for example, a capturing part), and the plastic material is moved in the sealed container by pressing from the reflective part side. Thus, the reflecting portion can be deformed. Alternatively, the reflecting portion can be deformed by storing a liquid or the like in a sealed container and closing the discharge port after part of the liquid is discharged from the discharge port.

  The “solar thermal power generation system” has at least one heat collecting part and at least one solar light collecting mirror for reflecting sunlight and irradiating the heat collecting part. There is one that uses liquid heat to heat a liquid and turn a turbine to generate electricity. In addition, it is preferable that a plurality of solar light collecting mirrors are arranged around the heat collecting portion. Preferably, a plurality of solar light collecting mirrors are arranged in a concentric circle shape or a concentric fan shape as shown in FIG. Moreover, it is preferable that the relative positions in the Z direction differ between the central part of the reflecting part or the structure and the peripheral part depending on the distance from the heat collecting part to each solar light collecting mirror.

  In the system in which the shortest distance among the distances between the heat collecting part and the solar light collecting mirror is 10 m or more, the solar of the present invention that does not reduce the light collecting efficiency while enabling the use of a lightweight film mirror. The effect of the light collecting mirror becomes remarkable. In particular, the present invention is preferably used in a tower type (beam-down type, tower top type, etc.) solar power generation system, but may be used in a trough type solar power generation system.

  A plurality of quadrangular or hexagonal sunlight collecting mirrors may be combined adjacent to each other to form a large pseudo-concave mirror. Preferably, a regular hexagonal shape is combined like a honeycomb structure. Since each solar light collecting mirror can be a concave mirror having an arbitrary curvature, the light collecting efficiency can be greatly improved.

  ADVANTAGE OF THE INVENTION According to this invention, the high condensing efficiency can be obtained, and also the manufacturing method of the solar condensing mirror which can manufacture a reflective surface of a desired curvature in large quantities, the solar condensing mirror, and it were used. A solar thermal power generation system can be provided.

It is a figure which shows the structure of the film mirror E. 1 is a perspective view of a solar thermal power generation system using a solar light collecting mirror according to the present invention. It is the figure which looked at the solar thermal power generation light system from the side. It is a perspective view of mirror SL for sunlight condensing. It is a figure which shows the manufacturing process of the mirror SL for solar light collection concerning 1st Embodiment. It is a figure which shows the manufacturing process of the mirror SL for solar light collection concerning 2nd Embodiment. It is a figure which shows the manufacturing process of the mirror SL for sunlight condensing concerning 3rd Embodiment. It is a figure which shows a mode that dust adhered when the surface layer of the film mirror was thick (a), and a mode that dust adhered when the surface layer of the film mirror was thin (b).

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings. FIG. 2 is a perspective view of a solar thermal power generation system using the solar light collecting mirror according to the present invention. FIG. 3 is a side view of such a solar thermal power generation light system. Although a beam-down solar power generation light system will be described here, it can also be applied to a tower-top solar power generation light system.

In FIG. 2, a relatively large-diameter condensing mirror 11 is formed by combining a plurality of mirrors along an elliptical shape, with three support towers 12 having a reflecting surface facing downward at a predetermined height position. Is retained. A heat exchange facility 13 having a heat collecting part 14 for converting sunlight L into heat energy is constructed below the condenser mirror 11. A large number of heliostats 15 are provided on the ground around the support tower 12 so as to surround the support tower 12. Light having a maximum incident irradiance of 5 kW / m ² or more enters the condenser mirror 11.

  In FIG. 3, each heliostat 15 includes a pillar part PL planted on the ground and a sunlight collecting mirror SL attached to the upper end of the pillar part PL. The pillar part PL can be rotated around an axis by an actuator (not shown), and the sunlight collecting mirror SL can change the elevation angle with respect to the pillar part PL by an actuator (not shown). The distance of the sunlight collecting mirror SL closest to the heat exchanger is 10 m or more in terms of the optical path length.

  FIG. 4 is a perspective view of the sunlight collecting mirror SL. The solar light collecting mirror SL is formed on a rectangular plate-like substrate (also referred to as a capturing portion) ST fixed on the pillar portion PL, a support body HL held on the substrate ST, and the support body HL. And a film mirror FM which is a reflection part. The support HL is in a solidified state, but before that, it is in a plastic state that can be arbitrarily deformed. The substrate ST is not necessarily provided, and the pillar portion PL may be directly joined to the solidified support body HL.

  Since the upper surface of the support HL is fixed in a rotational paraboloid shape centered on the axis X of the mirror, the reflection surface of the film mirror FM is also fixed in the rotational paraboloid shape. Therefore, when the sunlight L is incident on the sunlight collecting mirror SL, the sunlight L can be efficiently condensed on the heat collecting portion by reflecting the sunlight with the film mirror FM.

  FIG. 5 is a diagram illustrating a manufacturing process of the sunlight collecting mirror SL according to the present embodiment. As shown in FIG. 5A, a plastic material (here, thermosetting resin) HL is placed on the substrate ST, and a film mirror FM is placed thereon.

  Thereafter, as shown in FIG. 5 (b), the mold MD having a rotating paraboloid on the lower surface is approached from the film mirror FM side, and the plastic material HL is pressed through the film mirror FM to be molded. While maintaining this state, the substrate is heated from the surroundings with a heater (not shown), and the plastic material is cured to form the support HL.

  When the mold MD is retracted after the plastic material is cured, the film mirror FM pressed by the lower surface of the mold MD is formed on the paraboloid and the shape is maintained by the support HL that is fixed. Thus, the solar light collecting mirror SL can be manufactured. In addition, when the plastic material HL is pressed by the mold MD, a material that protrudes around the film mirror FM is generated, but this may be cut after fixing or left as it is.

  According to the present embodiment, a solar light collecting mirror SL having a highly accurate rotating paraboloid can be manufactured at a low cost at a factory, and it is lighter than a glass mirror and thus can be easily transported. System cost can be reduced.

  If the transfer surface of the mold MD is cylindrical (two-dimensional convex surface), in a so-called trough type solar thermal condensing system, a solar condensing mirror SL used to condense sunlight into a tube through which a heat storage medium flows is formed. it can. A trough-type solar heat collecting system is disclosed in Japanese Patent Application Laid-Open No. 2008-232524.

  FIG. 6 is a diagram illustrating a manufacturing process of the solar light collecting mirror SL according to another embodiment. Similar to the above-described embodiment, a plastic material (here, a visible light curable resin) HL is placed on the substrate ST serving as a capturing portion, and after the film mirror FM is placed thereon, A through-hole AP is formed in the center of the substrate ST, the plastic material HL, and the film mirror FM using the illustrated drill or the like.

  Thereafter, the bolt BT, which is a screw member, is inserted into the through-hole AP from the film mirror FM side and screwed into the nut NT disposed on the substrate ST side as shown in FIG. The material HL escapes to the periphery, and the portion around the hole on the film mirror FM side approaches the substrate ST. Accordingly, the reflection surface can be a pseudo-parabolic surface in which the inclination of the peripheral surface of the film mirror FM is changed according to the tightening amount of the bolt BT. When the desired shape is obtained, as shown in FIG. 6C, while maintaining this state, the plastic material is cured by visible light to form the support HL. When the bolt BT is tightened, a material that protrudes around the film mirror FM is generated. However, this material may be removed after being cured, or may be left solidified as it is. The bolt BT constitutes changing means.

  According to the present embodiment, it is possible to adjust the reflecting surface shape while actually reflecting the sunlight with the sunlight collecting mirror SL and confirming the collecting position at the site, so that the cost of the solar thermal power generation system can be reduced. Can be reduced.

  FIG. 7 is a diagram illustrating a manufacturing process of the solar light collecting mirror SL according to another embodiment. In this embodiment, a container-type substrate is used as a capturing unit. First, as shown in FIG. 7 (a), a container-like in-substrate ST having an open top, which is composed of a bottom plate BP having a hole AP closed by a lid CP in the center and a peripheral wall PW, is prepared. The liquid LQ is put into the substrate ST, and the upper part of the substrate ST is sealed while the film mirror FM is in contact with the upper surface of the liquid LQ. As a result, the inside of the substrate ST is sealed.

  Thereafter, as shown in FIG. 7B, when the lid CP is removed and the liquid LQ is discharged from the hole AP, the internal pressure is lowered, so that the film mirror FM on the center side of the peripheral wall PW having higher rigidity becomes the bottom plate. Deforms to approach BP. Thereby, the reflective surface of film mirror FM can be made into a pseudo paraboloid. When the film mirror FM has a desired shape, the hole AP is sealed with a lid CP as shown in FIG. The lid CP constitutes changing means.

  As shown by a dotted line in FIG. 7C, a ring-shaped member RG having an arbitrary thickness and diameter is arranged on the bottom plate BP, and abuts against the lower surface of the film mirror FM deformed when the fluid LQ is discharged. Therefore, it is possible to control the film mirror FM to have a desired shape by suppressing further deformation of the film mirror FM.

  According to the present embodiment, it is possible to adjust the reflecting surface shape while actually reflecting the sunlight with the sunlight collecting mirror SL and confirming the collecting position at the site, so that the cost of the solar thermal power generation system can be reduced. Can be reduced.

AP hole, through-hole BT bolt BP bottom plate CP lid FM film mirror HL support LQ liquid MD type NT nut PL pillar part PP peripheral wall RG ring-shaped member SL sunlight collecting mirror ST substrate

Claims (14)

A method of manufacturing a mirror for collecting sunlight,
Laying a deformable reflector on a plastic material;
Deforming the reflective portion and the plastic material;
And a step of fixing the shape of the plastic material.   2. The solar light collecting mirror according to claim 1, wherein the reflecting portion and the plastic material are deformed by pressing a molding die against the plastic material through the reflecting portion. Manufacturing method.   The method for manufacturing a solar light collecting mirror according to claim 2, wherein the shape of the plastic material is fixed by curing the plastic material.   The plastic material is disposed between the reflective portion and the substrate, and the reflective portion and the plastic material are deformed by bringing the reflective portion and at least a part of the substrate relatively close to each other. The manufacturing method of the mirror for sunlight condensing of Claim 1 characterized by these.   The solar light collection according to claim 4, wherein the reflection portion and the plastic material are deformed by connecting the reflection portion and the substrate with a screw member and tightening the screw member. Manufacturing method of optical mirror.   The solar light concentrating device according to claim 5, wherein the shape of the plastic material is fixed by fixing a distance of at least a part of the reflecting portion and the substrate using the screw member. Mirror manufacturing method.   The plastic material is a fluid contained in a container, and the reflective portion and the plastic material are deformed by discharging a part of the plastic material to the outside of the container. The manufacturing method of the mirror for sunlight condensing of Claim 1.   The method for manufacturing a solar light collecting mirror according to claim 7, wherein the shape of the plastic material is fixed by sealing the plastic material in a container.   The method for manufacturing a solar light collecting mirror according to claim 1, wherein the reflecting portion after deformation has a paraboloid of revolution.   The method for manufacturing a solar light collecting mirror according to claim 1, wherein the reflecting portion after deformation has a bowl-shaped reflecting surface.   The method for manufacturing a solar light collecting mirror according to claim 1, wherein the reflecting portion is elastically deformable.   A solar light collecting mirror, comprising: a support made of a plastic material capable of fixing at least one surface in a predetermined shape; and a reflecting portion laid on the one surface.   A capturing section that captures the plastic material; and a changing unit that changes the shape of the reflecting section by moving or removing the plastic material captured by the capturing section in a state where the reflecting section is laid. The solar light collecting mirror according to claim 12, comprising: A solar thermal power generation system,
It has at least 1 heat collecting part and the solar light collecting mirror according to claim 13, wherein the solar light collecting mirror reflects sunlight and irradiates the heat collecting part. And solar power generation system.