JP4513931B2 - Optical bodies, window materials, blinds, roll curtains, and shoji - Google Patents

Description

  The present invention relates to an optical body, a window material, a blind, a roll curtain, and a shoji. More specifically, the present invention relates to an optical body that selectively directs and reflects light in a specific wavelength band while transmitting light outside the specific wavelength band.

  In recent years, cases in which a layer that absorbs or reflects a part of sunlight is provided on architectural glass or car window glass such as high-rise buildings and houses are increasing. This is one of the energy-saving measures for the purpose of preventing global warming, and the purpose is to reduce the load of the cooling equipment as the light energy poured from the sun enters the window indoors and the indoor temperature rises. Yes. The light energy poured from sunlight occupies a large proportion of the visible region having a wavelength of 380 to 780 nm and the near infrared region having a wavelength of 780 to 2100 nm. Among these, the transmittance of the window in the latter wavelength region is irrelevant to human visibility, and is therefore an important factor that affects the performance as a highly transparent and highly heat-shielding window.

  As a method of shielding near infrared rays while maintaining transparency in the visible region, a method of providing a layer having a high reflectance in the near infrared region on the window glass and a layer having a high absorption factor in the near infrared region are used. There is a method of providing the glass.

  As for the former method, many techniques using an optical multilayer film, a metal-containing film, a transparent conductive film and the like as a reflective layer have already been disclosed (for example, see Patent Document 1). However, since such a reflective layer is provided on a flat window glass, it can only regularly reflect incident sunlight. For this reason, the light irradiated from the sky and specularly reflected reaches another outdoor building or the ground, is absorbed, changes to heat, and raises the ambient temperature. As a result, in the vicinity of buildings where such a reflective layer is applied to the entire window, there are problems such as local temperature rises and heat islands being increased in urban areas, and lawns not growing only on the surface irradiated with reflected light. Has occurred.

  As the latter method, many techniques using an organic dye film have been disclosed (for example, see Patent Documents 2 to 4). However, if such a dye film is pasted on the window glass, the light absorbed on the window surface is changed to heat, and part of it is transmitted indoors as radiant heat. There is a problem that the glass breaks due to thermal stress. Another problem is that it is difficult to use in high-rise buildings where the dye film has low weather resistance and cannot be frequently replaced.

International Publication No. 05/087680 Pamphlet Japanese Patent Laid-Open No. 06-299139 JP 09-316115 A JP 2001-89492 A

  Accordingly, an object of the present invention is to selectively reflect light in a specific wavelength band while optically transmitting light other than the specific wavelength band, a window material, a blind, a roll curtain, and a shoji Is to provide.

In order to solve the above problems, the present invention provides:
An optical layer having an incident surface on which light is incident;
A wavelength selective reflection film formed in the optical layer,
Incident angles (θ, φ) (where θ is an angle between a perpendicular to the incident surface and incident light incident on the incident surface or reflected light emitted from the incident surface, φ is a specific straight line in the incident surface, and Of light incident on the incident surface at an angle formed by incident light or reflected light projected onto the incident surface), light in a specific wavelength band is selectively directed in a direction other than regular reflection (−θ, φ + 180 °). While reflecting, it transmits light outside the specific wavelength band,
The wavelength selective reflection film has a first main surface and a second main surface,
The optical layer includes a first optical layer formed on the first main surface of the wavelength selective reflection film, and a second optical layer formed on the second main surface of the wavelength selective reflection film,
The first optical layer having a one-dimensional array structure body on a surface wavelength-selective reflective layer is formed,
An optical body in which the main axis of the structure is inclined in the arrangement direction of the structure with respect to the normal of the incident surface.

  In the present invention, light in a specific wavelength band can be directionally reflected and excluded from entering a predetermined space, and light outside the specific wavelength band can be taken into the predetermined space. Further, the reflected light intensity in a specific direction other than the regular reflection is stronger than the regular reflected light intensity, and can be sufficiently higher than the diffuse reflection intensity having no directivity.

  As described above, according to the present invention, light in a specific wavelength band is selectively directed and reflected, whereas light other than the specific wavelength band can be transmitted.

FIG. 1 is a cross-sectional view showing a configuration example of a directional reflector according to the first embodiment of the present invention. FIG. 2 is a perspective view showing a relationship between incident light incident on the directional reflector and reflected light reflected by the directional reflector. 3A to 3C are perspective views illustrating examples of the shape of the structure formed in the first optical layer. FIG. 4A is a perspective view showing an example of the shape of the structure formed in the first optical layer. FIG. 4B is a cross-sectional view showing the direction of inclination of the principal axis of the structure formed in the first optical layer. FIG. 5 is a cross-sectional view for explaining an example of the function of the directional reflector. FIG. 6 is a cross-sectional view for explaining an example of the function of the directional reflector. FIG. 7 is a cross-sectional view for explaining an example of the function of the directional reflector. FIG. 8 is a cross-sectional view for explaining an example of the function of the directional reflector. FIG. 9A is a cross-sectional view illustrating a relationship between a ridge line of a columnar structure, incident light, and reflected light. FIG. 9B is a plan view showing a relationship between a ridge line of a columnar structure, incident light, and reflected light. 10A to 10C are process diagrams for explaining an example of a method for manufacturing a directional reflector according to the first embodiment of the present invention. 11A to 11C are process diagrams for explaining an example of a method for manufacturing a directional reflector according to the first embodiment of the present invention. FIG. 12A is a plan view illustrating a configuration example of a structure of a directional reflector according to the second embodiment of the present invention. 12B is a cross-sectional view taken along line BB of the directional reflector illustrated in FIG. 12A. 12C is a cross-sectional view of the directional reflector shown in FIG. 12A along the line CC. FIG. 13A is a plan view showing a configuration example of a structure of a directional reflector according to the second embodiment of the present invention. 13B is a cross-sectional view of the directional reflector shown in FIG. 13A along the line BB. 13C is a cross-sectional view of the directional reflector shown in FIG. 13A along the line CC. FIG. 14A is a plan view illustrating a configuration example of a structure of a directional reflector according to the second embodiment of the present invention. 14B is a cross-sectional view of the directional reflector shown in FIG. 14A along the line BB. FIG. 15 is a cross-sectional view illustrating a configuration example of a directional reflector according to the third embodiment of the present invention. FIG. 16 is a cross-sectional view showing a configuration example of a directional reflector according to the fourth embodiment of the present invention. FIG. 17 is a perspective view showing a configuration example of a structure of a directional reflector according to the fourth embodiment of the present invention. FIG. 18 is a cross-sectional view showing a configuration example of a directional reflector according to the fifth embodiment of the present invention. 19A to 19C are cross-sectional views showing first to third configuration examples of the directional reflector according to the fifth embodiment of the present invention. FIG. 20 is a cross-sectional view showing a configuration example of a directional reflector according to the seventh embodiment of the present invention. 21A and 21B are cross-sectional views illustrating a first configuration example of a directional reflector according to the eighth embodiment of the present invention. 22A and 22B are cross-sectional views showing a second configuration example of the directional reflector according to the eighth embodiment of the present invention. FIG. 23 is a schematic diagram showing a configuration example of a directional reflector manufacturing apparatus according to the eighth embodiment of the present invention. FIG. 24 is a cross-sectional view showing a first configuration example of a directional reflector according to the ninth embodiment of the present invention. FIG. 25 is a cross-sectional view showing a second configuration example of the directional reflector according to the ninth embodiment of the present invention. FIG. 26 is a cross-sectional view showing a configuration example of a directional reflector according to the tenth embodiment of the present invention. FIG. 27 is a cross-sectional view showing a configuration example of a directional reflector according to the eleventh embodiment of the present invention. FIG. 28 is a cross-sectional view showing the shape of the molding surface of the aluminum mold of Example 1. FIG. 29 is a graph showing a spectral reflectance curve of Example 1. FIG. 30A is a plan view showing the shape of a master for producing optical films of Examples 2 to 4. FIG. 30B is a cross-sectional view taken along line BB of the master shown in FIG. 30A. FIG. 31 is a schematic diagram showing the configuration of a measuring apparatus for measuring the retroreflectance of a directional reflector. FIG. 32 is a graph showing the spectral transmittance of the optical films of Examples 2 to 4. FIG. 33 is a graph showing the spectral transmittance of the optical films of Comparative Examples 2 to 4. FIG. 34 is a diagram showing the evaluation results of the surface roughness of the optical film of Comparative Example 6. FIG. 35A is a plan view showing a shape of a master for producing optical films of Examples 7 to 11. FIG. FIG. 35B is a cross-sectional view along the line BB of the master shown in FIG. 35A. FIG. 36 is a graph showing the transmission characteristics of the optical films of Example 7 and Example 8. FIG. 37 is a graph showing the transmission characteristics of the optical films of Example 9 and Example 10. FIG. 38A is a graph showing the transmission characteristics of the optical films of Comparative Example 9 and Comparative Example 10, and FIG. 38B is a graph showing the reflection characteristics of the optical films of Comparative Example 9 and Comparative Example 10. FIG. 39A is a graph showing the transmission characteristics of the optical films of Comparative Examples 11 and 12, and FIG. 39B is a graph showing the reflection characteristics of the optical films of Comparative Examples 11 and 12. 40A is a graph showing the transmission characteristics of the optical film of Comparative Example 13, and FIG. 40B is a graph showing the reflection characteristics of the optical film of Comparative Example 13. FIG. 41 is a graph showing the sensitivity coefficient according to the test method of JIS R 3106. FIG. 42 is a diagram for explaining the film thickness of the wavelength selective reflection film.

Embodiments of the present invention will be described in the following order with reference to the drawings.
1. First embodiment (example in which structures are arranged one-dimensionally)
2. Second embodiment (example in which structures are two-dimensionally arranged)
3. Third embodiment (example using beads as a structure)
4). Fourth Embodiment (Example of louver type wavelength selective reflection film)
5). Fifth Embodiment (Example in which a self-cleaning effect layer is provided on the surface of a directional reflector)
6). Sixth Embodiment (Example in which a directional reflector is provided with a light scatterer)
7). Seventh embodiment (example in which a wavelength selective reflection film is directly formed on the surface of a window material)
8). Eighth Embodiment (Example in which the optical layer of the directional reflector has a two-layer structure)
9. Ninth Embodiment (Example in which a barrier layer is provided on the surface or inside of a directional reflector)
10. Tenth Embodiment (Example in which a hard coat layer is provided on the surface of a directional reflector)
11. Eleventh Embodiment (Example in which an antifouling layer is provided on a hard coat layer of a directional reflector)

<1. First Embodiment>
FIG. 1 is a cross-sectional view showing a configuration example of a directional reflector according to the first embodiment of the present invention. As shown in FIG. 1, the directional reflector 1 includes an optical layer 2 and a wavelength selective reflection film 3 formed inside the optical layer 2. The optical layer 2 includes a first optical layer 4 formed on the first main surface of the wavelength selective reflection film 3 and a second optical layer formed on the second main surface of the wavelength selective reflection film 3. 5. The directional reflector 1 has an incident surface S1 on which light such as sunlight is incident, and an output surface S2 from which light transmitted through the optical layer 2 is emitted from the incident surface S1.

  The directional reflector 1 has transparency. As transparency, it is preferable to have the range of the transmission map definition described later. The refractive index difference between the first optical layer 4 and the second optical layer 5 is preferably 0.010 or less, more preferably 0.008 or less, and still more preferably 0.005 or less. If the refractive index difference exceeds 0.010, the transmitted image tends to appear blurred. If it is in the range of more than 0.008 and not more than 0.010, there is no problem in daily life although it depends on the external brightness. If it is in the range of more than 0.005 and less than or equal to 0.008, the diffraction pattern is worrisome only for a very bright object such as a light source, but the outside scenery can be clearly seen. If it is 0.005 or less, the diffraction pattern is hardly a concern. Of the first optical layer 4 and the second optical layer 5, the optical layer on the side bonded to the window material 10 or the like may contain an adhesive as a main component. By setting it as such a structure, the directional reflector 1 can be bonded together to the window material 10 etc. with the optical layer which has an adhesive material as a main component. FIG. 1 shows an example in which the second optical layer 5 includes an adhesive as a main component, and the directional reflector 1 is bonded to the window material 10 or the like by the second optical layer 5. In addition, when setting it as such a structure, it is preferable that the refractive index difference of an adhesive is in the said range.

  It is preferable that the first optical layer 4 and the second optical layer 5 have the same optical characteristics such as refractive index. More specifically, the first optical layer 4 and the second optical layer 5 are preferably made of the same material having transparency in the visible region. By configuring the first optical layer 4 and the second optical layer 5 with the same material, the refractive indexes of both are equal, and thus the transparency of visible light can be improved. However, it should be noted that even if the same material is used as a starting source, the refractive index of the film finally produced may differ depending on the curing conditions in the film forming process. On the other hand, if the first optical layer 4 and the second optical layer 5 are made of different materials, the refractive indexes of the two are different, so that the light is refracted at the wavelength selective reflection film 3 and the transmitted image is There is a tendency to blur. In particular, when observing an object close to a point light source such as a distant electric lamp, there is a problem that the diffraction pattern is remarkably observed.

  It is preferable that the first optical layer 4 and the second optical layer 5 have transparency in the visible region. Here, the definition of transparency has two kinds of meanings: no light absorption and no light scattering. In general, when the term “transparent” is used, only the former may be indicated. In the present invention, it is necessary to provide both. The retroreflectors currently used are intended for visually recognizing display reflected light such as road signs and clothes for night workers. For example, even if they have scattering properties, they are in close contact with the underlying reflector. If so, the reflected light could be visually recognized. For example, even if an anti-glare process having a scattering property is applied to the front surface of the image display device for the purpose of imparting anti-glare properties, the same principle is that an image can be visually recognized. However, the directional reflector 1 according to the present invention is characterized in that it transmits light other than a specific wavelength that is directionally reflected. The directional reflector 1 is bonded to a transmissive body that mainly transmits the transmitted wavelength, and the transmitted light. Therefore, it is necessary to observe that there is no light scattering. However, depending on the application, the second optical layer 5 can be intentionally provided with scattering properties.

  The directional reflector 1 is preferably used by being bonded to a rigid body mainly having transparency with respect to the transmitted light having a wavelength other than the specific wavelength, for example, the window material 10 via an adhesive or the like. Examples of the window material 10 include window materials for buildings such as high-rise buildings and houses, and window materials for vehicles. When applying the directional reflector 1 to the window material for building, it is preferable to apply the directional reflector 1 to the window material 10 arranged particularly in the southeast to southwest direction. It is because a heat ray can be reflected more effectively by applying to the window material 10 in such a position. The directional reflector 1 can be used not only for a single-layer window glass but also for a special glass such as a multi-layer glass. Moreover, the window material 10 is not limited to what consists of glass, You may use what consists of a polymeric material which has transparency. It is preferable that the optical layer 2 has transparency in the visible region. This is because by having transparency in this way, when the optical body is bonded to the window material 10 such as a window glass, visible light can be transmitted and daylighting by sunlight can be secured. Moreover, as a bonding surface, it can be used not only on the outer surface of glass but also on the inner surface. Thus, when using for an inner surface, it is necessary to match the front and back of the unevenness | corrugation of the structure 11, and an in-plane direction so that a directional reflection direction may turn into the target direction.

  From the viewpoint of enabling the directional reflector 1 to be easily bonded to the window member 10, the directional reflector 1 preferably has flexibility. Examples of the shape of the directional reflector 1 include a film shape, a sheet shape, a plate shape, and a block shape, but are not particularly limited to these shapes.

  Moreover, the directional reflector 1 can be used in combination with another heat ray cut film. For example, a light absorbing coating film can be provided at the interface between the air and the optical layer 2. The directional reflector 1 can be used in combination with a hard coat layer, an ultraviolet cut layer, a surface antireflection layer, or the like. When these functional layers are used in combination, it is preferable to provide these functional layers at the interface between the directional reflector 1 and the air.

  Moreover, according to the use of the directional reflector 1, you may make it color the directional reflector 1 and provide designability. Thus, when designability is imparted, it is preferable that the optical layer 2 absorb only light in a specific wavelength band as long as the transparency is not impaired.

FIG. 2 is a perspective view showing a relationship between incident light incident on the directional reflector 1 and reflected light reflected by the directional reflector 1. The directional reflector 1 has an incident surface S1 on which the light L is incident. The directional reflector 1 selectively directs light L ₁ in a specific wavelength band in a direction other than regular reflection (−θ, φ + 180 °) among the light L incident on the incident surface S1 at an incident angle (θ, φ). While reflecting, it transmits light L ₂ other than the specific wavelength band. The directional reflector 1 is transparent to light other than the specific wavelength band. As transparency, it is preferable to have the range of the transmission map definition described later. Where θ is an angle formed between the perpendicular l ₁ to the incident surface S1 and the incident light L or the reflected light L ₁ . φ: An angle formed between a specific straight line l ₂ in the incident surface S1 and a component obtained by projecting the incident light L or the reflected light L ₁ onto the incident surface S1. Here, the specific straight line l ₂ in the incident surface is when the incident angle (θ, φ) is fixed and the directional reflector 1 is rotated about the perpendicular l ₁ with respect to the incident surface S ₁ of the directional reflector 1. , The axis that maximizes the reflection intensity in the φ direction (see FIGS. 3 and 4). However, when there are a plurality of axes (directions) at which the reflection intensity is maximum, one of them is selected as the straight line l ₂ . The angle θ rotated clockwise with respect to the perpendicular l ₁ is defined as “+ θ”, and the angle θ rotated counterclockwise is defined as “−θ”. The angle φ rotated clockwise with respect to the straight line l ₂ is defined as “+ φ”, and the angle φ rotated counterclockwise is defined as “−φ”.

  The light of a specific wavelength band that selectively and directionally reflects and the specific light that is transmitted vary depending on the application of the directional reflector 1. For example, when the directional reflector 1 is applied to the window member 10, the light in a specific wavelength band that is selectively directionally reflected is near-infrared light, and the light in the specific wavelength band that is transmitted is visible light. It is preferable. Specifically, it is preferable that light in a specific wavelength band that is selectively directionally reflected is mainly near-infrared light having a wavelength band of 780 nm to 2100 nm. By reflecting near infrared rays, when an optical body is bonded to a window material such as a glass window, an increase in temperature in the building can be suppressed. Therefore, cooling addition can be reduced and energy saving can be achieved. Here, the directional reflection means that the reflected light intensity in a specific direction other than the regular reflection is stronger than the regular reflected light intensity and sufficiently stronger than the diffuse reflection intensity having no directivity. Here, “reflecting” means that the reflectance in a specific wavelength band, for example, near infrared region is preferably 30% or more, more preferably 50% or more, and further preferably 80% or more. Transmitting means that the transmittance in a specific wavelength band, for example, in the visible light region is preferably 30% or more, more preferably 50% or more, and further preferably 70% or more.

  The direction φo for directional reflection is preferably −90 ° or more and 90 ° or less. This is because, when the directional reflector 1 is pasted on the window member 10, light in a specific wavelength band among light incident from the sky can be returned to the sky direction. When there are no tall buildings in the vicinity, the directional reflector 1 in this range is useful. Further, the direction of directional reflection is preferably in the vicinity of (θ, −φ). The vicinity means a deviation within a range of preferably within 5 degrees from (θ, −φ), more preferably within 3 degrees, and even more preferably within 2 degrees. By making this range, when the directional reflector 1 is pasted on the window member 10, among the light incident from above the buildings with the same height, the light of a specific wavelength band is efficiently introduced above other buildings. It is because it can return well. In order to realize such directional reflection, it is preferable to use a three-dimensional structure such as a spherical surface, a part of a hyperboloid, a triangular pyramid, a quadrangular pyramid, or a cone. The light incident from the (θ, φ) direction (−90 ° <φ <90 °) is based on the shape (θo, φo) direction (0 ° <θo <90 °, −90 ° <φo <90 °). ) Can be reflected. Alternatively, a columnar body extending in one direction is preferable. Light incident from the (θ, φ) direction (−90 ° <φ <90 °) is reflected in the (θo, −φ) direction (0 ° <θo <90 °) based on the inclination angle of the columnar body. Can do.

  Directional reflection of the light of the specific wavelength body is in the vicinity of retroreflection, that is, the reflection direction of the light of the specific wavelength body is near (θ, φ) with respect to the light incident on the incident surface S1 at the incident angle (θ, φ). It is preferable that This is because, when the directional reflector 1 is pasted on the window member 10, the light in the specific wavelength band can be returned to the sky among the light incident from the sky. Here, the vicinity is preferably within 5 degrees, more preferably within 3 degrees, and further preferably within 2 degrees. This is because, when the directional reflector 1 is pasted on the window member 10 within this range, light in a specific wavelength band out of light incident from above can be efficiently returned to the sky. In addition, when the infrared light irradiation part and the light receiving part are adjacent to each other as in an infrared sensor or infrared imaging, the retroreflection direction must be equal to the incident direction, but sensing from a specific direction as in the present invention. If it is not necessary to do so, it is not necessary to have the exact same direction.

  With respect to the mapping definition for a wavelength band having transparency, the value when an optical comb of 0.5 mm is used is preferably 50 or more, more preferably 60 or more, and even more preferably 75 or more. When the value of the map definition is less than 50, the transmitted image tends to appear blurred. If it is 50 or more and less than 60, it depends on the brightness of the outside, but there is no problem in daily life. If it is 60 or more and less than 75, only the very bright object such as a light source is concerned about the diffraction pattern, but the outside scenery can be clearly seen. If it is 75 or more, the diffraction pattern is hardly a concern. Furthermore, the total value of the mapping definition values measured using optical combs of 0.125 mm, 0.5 mm, 1.0 mm, and 2.0 mm is preferably 230 or more, more preferably 270 or more, and further preferably 350 or more. It is. If the total value of the map definition is less than 230, the transmitted image tends to appear blurred. If it is 230 or more and less than 270, it depends on the external brightness, but there is no problem in daily life. If it is 270 or more and less than 350, the diffraction pattern is worrisome only for a very bright object such as a light source, but the outside scenery can be clearly seen. If it is 350 or more, the diffraction pattern is hardly a concern. Here, the value of the mapping definition is measured according to JIS K7105 using ICM-1T manufactured by Suga Test Instruments. However, when the wavelength to be transmitted is different from the wavelength of the D65 light source, it is preferable to perform measurement after calibrating with a filter having a wavelength to be transmitted.

The haze with respect to the wavelength band having transparency is preferably 6% or less, more preferably 4% or less, and still more preferably 2% or less. This is because if the haze exceeds 6%, the transmitted light is scattered and it looks cloudy. Here, haze is measured by a measuring method defined in JIS K7136 using HM-150 made by Murakami Color. However, when the wavelength to be transmitted is different from the wavelength of the D65 light source, it is preferable to perform measurement after calibrating with a filter having a wavelength to be transmitted. The incident surface S1, preferably the incident surface S1 and the exit surface S2 of the directional reflector 1 have smoothness that does not reduce the mapping definition. Specifically, the arithmetic average roughness Ra of the entrance surface S1 and the exit surface S2 is preferably 0.08 μm or less, more preferably 0.06 μm or less, and even more preferably 0.04 μm or less. The arithmetic average roughness Ra is calculated as a roughness parameter by measuring the surface roughness of the incident surface, obtaining a roughness curve from a two-dimensional sectional curve. Measurement conditions are based on JIS B0601: 2001. The measurement apparatus and measurement conditions are shown below.
Measuring device: Fully automatic fine shape measuring machine Surfcoder ET4000A (Kosaka Laboratory Ltd.)
λc = 0.8mm, evaluation length 4mm, cutoff x5 times Data sampling interval 0.5μm

(First optical layer)
The first optical layer 4 is, for example, a support for supporting the wavelength selective reflection film 3. The first optical layer 4 is also for improving the transmission map definition and the total light transmittance and protecting the wavelength selective reflection film 3. The first optical layer 4 has, for example, a film shape, a sheet shape, a plate shape, or a block shape. From the viewpoint of enabling the directional reflector 1 to be easily bonded to the window member 10, the first optical layer 4 is preferably in the form of a film or a sheet. As a material for the first optical layer 4, for example, a thermoplastic resin such as polycarbonate, an ionizing radiation curable resin such as acrylic, or the like can be used.

Further, from the viewpoint of imparting design properties to the directional reflector 1, the window material 10, and the like, it is preferable that the first optical layer 4 has a characteristic of absorbing light having a specific wavelength in the visible region. The pigment dispersed in the resin may be either an organic pigment or an inorganic pigment, but it is particularly preferable to use an inorganic pigment having high weather resistance. Specifically, zircon gray (Co, Ni-doped ZrSiO ₄ ), praseodymium yellow (Pr-doped ZrSiO ₄ ), chrome titanium yellow (Cr, Sb-doped TiO ₂ or Cr, W-doped TiO ₂ ), chrome green (Cr ₂ O ₃ ), peacock ((CoZn) O (AlCr) ₂ O ₃ ), Victoria Green ((Al, Cr) ₂ O ₃ ), bitumen (CoO · Al ₂ O ₃ · SiO ₂ ), vanadium zirconium blue (V-doped) ZrSiO ₄ ), chromium tin pink (Cr-doped CaO · SnO ₂ · SiO ₂ ), ceramic red (Mn-doped Al ₂ O ₃ ), salmon pink (Fe-doped ZrSiO ₄ ) and other inorganic pigments, azo pigments and phthalocyanine pigments And organic pigments.

  The first optical layer 4 includes, for example, structures 11 that are one-dimensionally arranged on the surface on which the wavelength selective reflection film 3 is formed. The pitch P of the structures 11 is preferably 30 μm to 5 mm, more preferably 50 μm to 1 mm, and still more preferably 50 μm to 500 μm. If the pitch of the structures 11 is less than 30 μm, it is difficult to make the shape of the structures 11 as desired, and it is generally difficult to make the wavelength selective characteristics of the wavelength selective reflection film 3 steep. Therefore, part of the transmission wavelength may be reflected. When such reflection occurs, diffraction occurs and even higher-order reflection is visually recognized, so that the transparency tends to be felt poorly. Further, when the pitch of the structures 11 exceeds 5 mm, when considering the shape of the structures 11 necessary for directional reflection, the necessary film thickness is increased and flexibility is lost, and the structure 11 is bonded to a rigid body such as the window material 10. It becomes difficult.

  Further, the shape of the structure 11 formed on the surface of the first optical layer 4 is not limited to one type, and a plurality of types of structures 11 are formed on the surface of the first optical layer 4. You may do it. When a plurality of types of structures 11 are provided on the surface, a predetermined pattern composed of a plurality of types of structures 11 may be periodically repeated. Further, depending on desired characteristics, a plurality of types of structures 11 may be formed randomly (non-periodically).

  3A to 3C are perspective views illustrating examples of the shape of the structure formed in the first optical layer. The structure 11 is a columnar convex portion extending in one direction, and the columnar structures 11 are arranged one-dimensionally in one direction. Since the wavelength selective reflection film 3 is formed on the structure 11, the shape of the wavelength selective reflection film 3 has the same shape as the surface shape of the structure 11.

  Examples of the shape of the structure 11 include a prism shape shown in FIG. 3A, a shape shown in FIG. 3B in which the top of the prism shape is rounded, a cylindrical shape shown in FIG. 3C, or an inverted shape thereof. . Moreover, the shape of the structure 11 is not limited to the shape shown in FIGS. 3A to 3C or the inverted shape thereof, and may be a toroidal shape, a hyperbolic column shape, an elliptical column shape, a polygonal column shape, or a free-form surface shape. Good. When the structure 11 has a prism shape, the inclination angle θ of the prism-shaped structure 11 is, for example, 45 °. When applied to the window member 10, the structure 11 preferably has a flat surface or curved surface with an inclination angle inclined by 45 ° or more as much as possible from the viewpoint of reflecting a large amount of light incident from above and returning it to the sky. By adopting such a shape, the incident light returns to the sky with almost one reflection, so that the incident light can be efficiently reflected in the sky direction even if the reflectance of the wavelength selective reflection film 3 is not so high. This is because light absorption in the selective reflection film 3 can be reduced.

Further, as shown in FIG. 4A, the shape of the structure 11 may be asymmetric with respect to the perpendicular l ₁ perpendicular to the incident surface S1 of the directional reflector 1. In this case, the main axis l _m of the structure 11 is inclined in the arrangement direction a of the structures 11 with respect to the perpendicular l ₁ . Here, the main axis l _m of the structure 11 means a straight line passing through the midpoint of the bottom of the structure cross section and the vertex of the structure. When the directional reflector 1 is pasted on the window member 10 arranged perpendicular to the ground, as shown in FIG. 4B, the main axis l _m of the structure 11 has the vertical axis l ₁ as a reference. It is preferable to incline downward (on the ground side). In general, the heat inflow through the window is mostly in the time zone around noon, and the altitude of the sun is often higher than 45 °. Therefore, by adopting the above shape, the light incident from these high angles can be efficiently used. This is because it can be reflected upward. 4A and 4B show an example in which the prism-shaped structure 11 has an asymmetric shape with respect to the perpendicular l ₁ . The structure 11 other than the prism shape may be asymmetric with respect to the perpendicular l ₁ . For example, the corner cube body may have an asymmetric shape with respect to the perpendicular l ₁ .

(Second optical layer)
The second optical layer 5 is for improving the transmission map definition and the total light transmittance and protecting the wavelength selective reflection film 3. As a material of the second optical layer 5, for example, a thermoplastic resin such as polycarbonate, an ionizing radiation curable resin such as acrylic, or the like can be used. Alternatively, the second optical layer 5 may be an adhesive layer, and the directional reflector 1 may be bonded to the window material 10 via the adhesive layer. For example, a pressure sensitive adhesive (PSA), an ultraviolet curable resin, or the like can be used as the material of the adhesive layer.

Moreover, in order to give the directional reflector 1 a design property, the second optical layer 5 may have a function of absorbing light of a specific wavelength. As the 2nd optical layer 5 which has such a function, what pigmented resin which is the main component of the 2nd optical layer 5 can be used, for example. The pigment dispersed in the resin may be either an organic pigment or an inorganic pigment, but it is particularly preferable to use an inorganic pigment having high weather resistance. Specifically, zircon gray (Co, Ni-doped ZrSiO ₄ ), praseodymium yellow (Pr-doped ZrSiO ₄ ), chrome titanium yellow (Cr, Sb-doped TiO ₂ or Cr, W-doped TiO ₂ ), chrome green (Cr ₂ O ₃ ), peacock ((CoZn) O (AlCr) ₂ O ₃ ), Victoria Green ((Al, Cr) ₂ O ₃ ), bitumen (CoO · Al ₂ O ₃ · SiO ₂ ), vanadium zirconium blue (V-doped) ZrSiO ₄ ), chromium tin pink (Cr-doped CaO · SnO ₂ · SiO ₂ ), ceramic red (Mn-doped Al ₂ O ₃ ), salmon pink (Fe-doped ZrSiO ₄ ) and other inorganic pigments, azo pigments and phthalocyanine pigments And organic pigments.

(Wavelength selective reflection film)
The wavelength selective reflection film 3 is, for example, a laminated film, a transparent conductive film, or a functional film. Moreover, it is good also as a wavelength selection film | membrane combining 2 or more of a laminated film, a transparent conductive film, and a functional film. The film thickness of the wavelength selective reflection film 3 is preferably 20 μm, more preferably 5 μm or less, and further preferably 1 μm or less. When the film thickness of the wavelength selective reflection film 3 exceeds 20 μm, the optical path through which the transmitted light is refracted becomes long, and the transmitted image tends to appear distorted. As a method for forming the wavelength selective reflection film, for example, a sputtering method, a vapor deposition method, a dip coating method, a die coating method, or the like can be used.
Hereinafter, the laminated film, the transparent conductive film, or the functional film will be sequentially described.

(Laminated film)
The laminated film is, for example, a laminated film obtained by alternately laminating low refractive index layers and high refractive index layers having different refractive indexes. Alternatively, the multilayer film is, for example, a multilayer formed by alternately laminating a metal layer having a high reflectance in the infrared region and an optical transparent layer having a high refractive index in the visible region and functioning as an antireflection layer, or a transparent conductive film. It is a membrane.

  The metal layer having high reflectivity in the infrared region may be, for example, a simple substance such as Au, Ag, Cu, Al, Ni, Cr, Ti, Pd, Co, Si, Ta, W, Mo, Ge, or a simple substance thereof. The main component is an alloy containing two or more kinds. Of these, Ag-based, Cu-based, Al-based, Si-based, or Ge-based materials are preferred among these. When an alloy is used as the material of the metal layer, the metal layer is mainly composed of AlCu, AlTi, AlCr, AlCo, AlNdCu, AlMgSi, AgPdCu, AgPdTi, AgCuTi, AgPdCa, AgPdMg, AgPdFe, Ag, or SiB. It is preferable to do. In order to suppress corrosion of the metal layer, it is preferable to add materials such as Ti and Nd to the metal layer. In particular, when Ag is used as the material of the metal layer, it is preferable to add the above material.

  The optical transparent layer is an optical transparent layer that has a high refractive index in the visible region and functions as an antireflection layer. The optical transparent layer contains, as a main component, a high dielectric material such as niobium oxide, tantalum oxide, or titanium oxide. The transparent conductive film includes, for example, main components such as zinc oxide and indium-doped tin oxide.

  The laminated film is not limited to a thin film made of an inorganic material, and may be constituted by laminating a thin film made of a polymer material or a layer in which fine particles are dispersed in a polymer. Further, for the purpose of preventing oxidative degradation of the lower layer metal during the formation of the optical transparent layer, a thin buffer layer such as Ti of about several nm may be provided at the interface of the optical transparent layer to be formed. Here, the buffer layer is a layer for suppressing oxidation of a metal layer or the like as a lower layer by being oxidized by itself during upper film formation.

(Transparent conductive film)
The transparent conductive film is a transparent conductive film whose main component is a conductive material having transparency in the visible region. The transparent conductive film contains, for example, a transparent conductive material such as tin oxide, zinc oxide, a carbon nanotube-containing body, indium-doped tin oxide, indium-doped zinc oxide, and antimony-doped tin oxide as a main component. Alternatively, a layer in which nanoparticles, nanorods, and nanowires of conductive materials such as nanoparticles and metals are dispersed in a resin at a high concentration may be used.

(Functional membrane)
The functional film is mainly composed of a chromic material whose reflection performance is reversibly changed by an external stimulus. The chromic material is a material that reversibly changes its structure by an external stimulus such as heat, light, or an intruding molecule. As the chromic material, for example, a photochromic material, a thermochromic material, a gas chromic material, or an electrochromic material can be used.

A photochromic material is a material that reversibly changes its structure by the action of light. The photochromic material can reversibly change various physical properties such as reflectance and color by irradiation with light such as ultraviolet rays. As the photochromic material, for example, transition metal oxides such as TiO ₂ , WO ₃ , MoO ₃ , and Nb ₂ O ₅ doped with Cr, Fe, Ni, or the like can be used. Moreover, wavelength selectivity can also be improved by laminating | stacking the film | membrane from which these films and refractive indexes differ.

A thermochromic material is a material that reversibly changes its structure by the action of heat. The photochromic material can reversibly change various physical properties such as reflectance and color by heating. For example, VO ₂ can be used as the thermochromic material. Further, for the purpose of controlling the transition temperature and the transition curve, elements such as W, Mo, and F can be added. Further, a laminated structure in which a thin film mainly composed of a thermochromic material such as VO ₂ is sandwiched between antireflection layers mainly composed of a high refractive index body such as TiO ₂ or ITO may be employed.
Alternatively, a photonic lattice such as cholesteric liquid crystal can be used. Cholesteric liquid crystals can selectively reflect light with a wavelength according to the layer spacing, and this layer spacing changes with temperature, so that physical properties such as reflectance and color can be reversibly changed by heating. . At this time, it is possible to widen the reflection band by using several cholesteric liquid crystal layers having different layer intervals.

An electrochromic material is a material that can reversibly change various physical properties such as reflectance and color by electricity. As the electrochromic material, for example, a material that reversibly changes its structure by applying a voltage can be used. More specifically, as the electrochromic material, for example, a reflection-type light control material whose reflection characteristics are changed by doping or dedoping such as proton can be used. Specifically, the reflective dimming material is a material that can control its optical properties to a transparent state, a mirror state, and / or an intermediate state thereof by an external stimulus. Examples of such reflective light-modulating materials include magnesium and nickel alloy materials, alloy materials mainly composed of magnesium and titanium alloy materials, WO ₃ and acicular crystals having selective reflectivity in microcapsules. A confined material or the like can be used.

As a specific functional film configuration, for example, on the second optical layer, the above alloy film, a catalyst film containing Pd or the like, a buffer layer such as thin Al, an electrolyte layer such as Ta2O5, WO3 containing protons, etc. A structure in which an ion storage layer and a transparent conductive film are stacked can be used. Alternatively, a configuration in which a transparent conductive film, an electrolyte layer, an electrochromic layer such as WO _3, and a transparent conductive film are stacked on the second optical layer can be used. In these configurations, by applying a voltage between the transparent conductive film and the counter electrode, protons contained in the electrolyte layer are doped or dedoped into the alloy film. Thereby, the transmittance | permeability of an alloy layer changes. In order to improve wavelength selectivity, it is desirable to laminate an electrochromic material with a high refractive index material such as TiO ₂ or ITO. As another configuration, a configuration in which a transparent conductive film, an optical transparent layer in which microcapsules are dispersed, and a transparent electrode are stacked on the second optical layer can be used. In this configuration, by applying a voltage between both transparent electrodes, the acicular crystal in the microcapsule is in a transmission state in which it is oriented, or by removing the voltage, the acicular crystal is directed in all directions to be in a wavelength selective reflection state. can do.

(Function of directional reflector)
5 and 6 are cross-sectional views for explaining an example of the function of the directional reflector. Here, as an example, the case where the shape of the structure is a prism shape with an inclination angle of 45 ° will be described as an example.
As shown in FIG. 5, some of the near infrared rays L ₁ out of the sunlight incident on the directional reflector 1 are directionally reflected in the sky direction as much as the incident direction, whereas the visible light L _{2 is} reflected. Passes through the directional reflector 1.

Further, as shown in FIG. 6, is incident on the directional reflector 1, light reflected by the reflecting film surface of the wavelength-selective reflective layer 3, at a rate corresponding to the incident angle, the component L _A of the sky reflected sky It is separated into a component L _B not reflected. The component L _B not reflected toward the sky is totally reflected at the interface between the second optical layer 4 and the air is reflected in a direction different from the final incident direction.

The incident angle of light alpha, the refractive index of the first optical layer 4 n, the reflectance of the wavelength-selective reflective layer 3 is R, the ratio x of the sky reflection component L _A to the total incident component the following equation (1 ).
x = (sin (45−α ′) + cos (45−α ′) / tan (45 + α ′)) / (sin (45−α ′) + cos (45−α ′)) × R ² (1)
However, α ′ = sin ⁻¹ (sin α / n)

If the proportion of the component L _B not reflected toward the sky increases, the percentage of incident light is reflected over is reduced. In order to improve the sky reflection ratio, it is effective to devise the shape of the wavelength selective reflection film 3, that is, the shape of the structure 11 of the first optical layer 4. For example, in order to improve the proportion of the sky reflection, the shape of the structure 11 is preferably a cylindrical shape shown in FIG. 3C or an asymmetric shape shown in FIG. By making such a shape, even if it is not possible to reflect the light in exactly the same direction as the incident light, increase the proportion of the light that is incident from the upper direction, such as architectural window material, reflected upward. Is possible. As shown in FIGS. 7 and 8, the two shapes shown in FIGS. 3C and 4 require only one reflection of the incident light by the wavelength selective reflection film 3, and the final reflection component is shown in FIG. It is possible to increase more than the shape that reflects twice. For example, when two-time reflection is used, if the reflectance for a certain wavelength of the wavelength selective reflection film 3 is 80%, the sky reflectance is 64%, but if the reflection is performed once, the sky reflectance is 80%. Become.

FIG. 9 shows the relationship between the ridge line l ₃ of the columnar structure 11 and the incident light L and reflected light L ₁ . The directional reflector 1 selectively selects light L ₁ in a specific wavelength band (θo, −φ) in the direction (0 ° <θo <) among the light L incident on the incident surface S1 at an incident angle (θ, φ). It is preferable that light L ₂ other than the specific wavelength band is transmitted while being directionally reflected at 90 °. It is because the light of a specific wavelength band can be reflected in the sky direction by satisfying such a relationship. Where θ is an angle formed between the perpendicular l ₁ to the incident surface S1 and the incident light L or the reflected light L ₁ . φ: An angle formed by a straight line l ₂ perpendicular to the ridge line l ₃ of the columnar structure 11 in the incident surface S1 and a component obtained by projecting the incident light L or the reflected light L ₁ onto the incident surface S1. The angle θ rotated clockwise with respect to the perpendicular l ₁ is defined as “+ θ”, and the angle θ rotated counterclockwise is defined as “−θ”. The angle φ rotated clockwise with respect to the straight line l ₂ is defined as “+ φ”, and the angle φ rotated counterclockwise is defined as “−φ”.

(Manufacturing method of directional reflector)
Hereinafter, with reference to FIG. 10 and FIG. 11, an example of the manufacturing method of the directional reflector which concerns on the 1st Embodiment of this invention is demonstrated.
First, a mold having the same concavo-convex shape as the structure 11 or its inverted shape is formed by, for example, a cutting tool or laser processing. Next, the uneven shape of the mold is transferred to a film-like or sheet-like resin material using, for example, a melt extrusion method or a transfer method. Examples of the transfer method include a method of pouring an ionizing ray curable resin into a mold and irradiating the ionizing ray to cure, and a method of applying heat and pressure to the resin to transfer the shape. Thereby, as shown to FIG. 10A, the 1st optical layer 4 which has the structure 11 in one main surface is formed. Next, as shown in FIG. 10B, the wavelength selective reflection film 3 is formed on one main surface of the first optical layer 4. Examples of the method for forming the wavelength selective reflection film 3 include sputtering, vapor deposition, CVD (Chemical Vapor Deposition), dip coating, die coating, wet coating, and spray coating. It is preferable to select the film forming method appropriately according to the shape of the structure 11 and the like.

Next, as shown in FIG. 10C, an uncured resin 21 is applied onto the wavelength selective reflection film 3. As the resin 21, for example, a thermoplastic resin or an ionizing radiation curable resin can be used. As the ionizing radiation curable resin, an ultraviolet curable resin is preferable. Next, as shown in FIG. 11A, the peeling film 22 is placed on the resin 21, and the resin surface is molded. Next, as shown in FIG. 11B, the resin 21 is cured by irradiating the resin 21 with UV light from the light source 23 or by cooling the resin 21. Next, as shown in FIG. 11C, the peeling film 22 is peeled from the cured resin 21. Thereby, the second optical layer 5 having a smooth surface is formed on the wavelength selective reflection film 3. At this time, it is also possible to use a film that is transparent to light having a wavelength that is transmitted by the wavelength selective reflection film and ionizing rays without using the peeling film 22 and to be used as an optical body without peeling. Furthermore, the adhesive component dissolved in the solvent is thickly applied, leveled and flattened, and then the release film 22 is covered to form an optical body having the adhesive formed on one side.
As described above, the directional reflector 1 in which the wavelength selective reflection film having a desired shape is provided inside the optical layer 2 is obtained.

<2. Second Embodiment>
FIGS. 12-14 is sectional drawing which shows the structural example of the structure of the directional reflector which concerns on the 2nd Embodiment of this invention. In the second embodiment, portions corresponding to those in the first embodiment are denoted by the same reference numerals. The second embodiment is different from the first embodiment in that the structures 11 are two-dimensionally arranged on one main surface of the first optical layer 4.

  The structures 11 are two-dimensionally arranged on one main surface of the first optical layer 4. This arrangement is preferably the arrangement in the closest packed state. For example, a dense array such as a square dense array, a delta dense array, or a hexagonal dense array is formed on one main surface of the first optical layer 4 by two-dimensionally arranging the structures 11 in the most densely packed state. . The square dense array is a structure in which the structures 11 having a square bottom surface are arranged in a square dense form. The delta dense array is a structure in which the structures 11 having a triangular bottom surface are arranged in a hexagonal dense form. In the hexagonal close-packed array, the structures 11 having hexagonal bottom surfaces are arranged in a hexagonal close-packed shape.

  The structure 11 is, for example, a convex or concave portion such as a corner cube shape, a hemispherical shape, a semi-elliptical spherical shape, a prism shape, a free-form surface shape, a polygonal shape, a conical shape, a polygonal pyramid shape, a truncated cone shape, or a parabolic shape. is there. The bottom surface of the structure 11 has, for example, a circular shape, an elliptical shape, or a polygonal shape such as a triangular shape, a quadrangular shape, a hexagonal shape, or an octagonal shape. FIG. 12 shows an example of a square dense array in which the structures 11 having a rectangular bottom surface are two-dimensionally arranged in the most densely packed state. FIG. 13 shows an example of a delta dense array in which the structures 11 having a hexagonal bottom surface are two-dimensionally arranged in the most densely packed state. Further, FIG. 14 shows an example of a hexagonal close-packed array in which the structures 11 having triangular bottom surfaces are two-dimensionally arranged in the close-packed state. Moreover, it is preferable that the pitches P1 and P2 of the structures 11 are appropriately selected according to desired optical characteristics. When the principal axis of the structure 11 is tilted with respect to a perpendicular perpendicular to the incident surface of the directional reflector 1, the principal axis of the structure 11 is set in at least one arrangement direction of the two-dimensional arrangement of the structures 11. It is preferable to tilt. When sticking the directional reflector 1 to a window member arranged perpendicular to the ground, it is preferable that the main axis of the structure 11 is inclined downward (on the ground side) with respect to the vertical line.

<3. Third Embodiment>
FIG. 15 is a cross-sectional view illustrating a configuration example of a directional reflector according to the third embodiment of the present invention. In 3rd Embodiment, the same code | symbol is attached | subjected to the location corresponding to 1st Embodiment. As shown in FIG. 15, the third embodiment is different from the first embodiment in that a bead 31 is provided instead of the structure.

  The beads 31 are embedded in one main surface of the first optical layer 4 so that a part of the beads 31 protrudes from the one main surface. The focal layer 32, the wavelength selective reflection film 3, and the second optical layer are sequentially laminated on one main surface of the first optical layer 4 in which the beads 31 are embedded. The beads 31 have, for example, a spherical shape. It is preferable that the beads 31 have transparency. The beads 31 are mainly composed of an inorganic material such as glass or an organic material such as a polymer resin.

<4. Fourth Embodiment>
FIG. 16 is a cross-sectional view showing a configuration example of a directional reflector according to the fourth embodiment of the present invention. In 4th Embodiment, the same code | symbol is attached | subjected to the location same as 1st Embodiment, and description is abbreviate | omitted. In the fourth embodiment, a plurality of wavelength selective reflection films 3 inclined with respect to the light incident surface are provided in the optical layer 2, and the wavelength selective reflection films 3 are arranged in parallel to each other. This is different from the first embodiment.

  FIG. 17 is a perspective view showing a configuration example of a structure of a directional reflector according to the fourth embodiment of the present invention. The structure 11 is a triangular prism-shaped convex portion extending in one direction, and the columnar structures 11 are arranged one-dimensionally in one direction. The cross section perpendicular to the extending direction of the structure 11 has, for example, a right triangle shape. The wavelength selective reflection film 3 is formed on the inclined surface on the acute angle side of the structure 11 by a directional thin film forming method such as a vapor deposition method or a sputtering method.

  According to the fourth embodiment, a plurality of wavelength selective reflection films 3 are arranged in parallel in the optical layer 5. Thereby, the frequency | count of reflection by the wavelength selection reflection film 3 can be reduced compared with the case where the structure 11 of a corner cube shape or a prism shape is formed. Therefore, the reflectance can be increased and the absorption of light by the wavelength selective reflection film 3 can be reduced.

<5. Fifth Embodiment>
FIG. 18 is a cross-sectional view showing a configuration example of a directional reflector according to the fifth embodiment of the present invention. In the fifth embodiment, the same portions as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. As shown in FIG. 18, the fifth embodiment is different from the first embodiment in that a self-cleaning effect layer 6 that exhibits a cleaning effect is further provided on the incident surface of the directional reflector 1. . The self-cleaning effect layer 6 contains, for example, a photocatalyst. As the photocatalyst, for example, TiO ₂ can be used.

  As described above, the directional reflector 1 is characterized in that it selectively reflects light in a specific wavelength band. When the directional reflector 1 is used outdoors or in a room with a lot of dirt, the surface is always optically transparent because light is scattered by the dirt adhering to the surface and the directional reflection characteristics are lost. preferable. Therefore, it is preferable that the surface is excellent in water repellency and hydrophilicity, and the surface automatically exhibits a cleaning effect.

  According to the fifth embodiment, since the self-cleaning effect layer 6 is formed on the incident surface of the directional reflector 1, water repellency, hydrophilicity, and the like can be imparted to the incident surface. Therefore, it is possible to suppress the adhesion of dirt and the like to the incident surface and to suppress the reduction of the directional reflection characteristics.

<6. Sixth Embodiment>
The sixth embodiment is different from the first embodiment in that light having a specific wavelength is directionally reflected while light other than the specific wavelength is scattered. The directional reflector 1 includes a light scatterer that scatters incident light. This scatterer is provided, for example, at least one place among the surface of the optical layer 2, the inside of the optical layer 2, and between the wavelength selective reflection film 3 and the optical layer 2. The light scatterer is preferably provided between at least one of the wavelength selective reflection film 3 and the second optical layer 5, the inside of the second optical layer 5, and the surface of the second optical layer 5. It has been. When the directional reflector 1 is bonded to a support such as a window material, it can be applied to both the indoor side and the outdoor side. When the directional reflector 1 is bonded to the outdoor side, it is preferable to provide a light scatterer that scatters light other than the specific wavelength only between the wavelength selective reflection film 3 and a support such as a window material. This is because, when the directional reflector 1 is bonded to a support such as a window material, if a light scatterer exists between the wavelength selective reflection film 3 and the incident surface, the directional reflection characteristics are lost. In addition, when the directional reflector 1 is bonded to the indoor side, it is preferable to provide a light scatterer between the wavelength selective reflection film 3 and the emission surface opposite to the bonded surface.

  FIG. 19A is a cross-sectional view showing a first configuration example of a directional reflector according to the sixth embodiment of the present invention. As shown in FIG. 19A, the second optical layer 5 includes a resin and fine particles 12. The fine particles 12 have a refractive index different from that of the resin that is the main constituent material of the second optical layer 5. As the fine particles 12, for example, at least one of organic fine particles and inorganic fine particles can be used. Further, as the fine particles 12, hollow fine particles may be used. Examples of the fine particles 12 include inorganic fine particles such as silica and alumina, and organic fine particles such as styrene, acrylic, and copolymers thereof, and silica fine particles are particularly preferable.

  FIG. 19B is a cross-sectional view showing a second configuration example of the directional reflector according to the sixth embodiment of the present invention. As shown in FIG. 19B, the directional reflector 1 further includes a light diffusion layer 7 on the surface of the second optical layer 5. The light diffusion layer 7 includes, for example, a resin and fine particles. As the fine particles, the same fine particles as in the first example can be used.

  FIG. 19C is a cross-sectional view illustrating a third configuration example of the directional reflector according to the sixth embodiment of the present invention. As shown in FIG. 19C, the directional reflector 1 further includes a light diffusion layer 7 between the wavelength selective reflection film 3 and the second optical layer 5. The light diffusion layer 7 includes, for example, a resin and fine particles. As the fine particles, the same fine particles as in the first example can be used.

  According to the sixth embodiment, it is possible to directionally reflect light in a specific wavelength band such as infrared rays and to scatter light other than the specific wavelength pair such as visible light. Therefore, the directional reflector 1 can be fogged to impart design properties to the directional reflector 1.

<7. Seventh Embodiment>
FIG. 20 is a cross-sectional view showing a configuration example of a directional reflector according to the seventh embodiment of the present invention. In the seventh embodiment, the same portions as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. The seventh embodiment is different from the first embodiment in that the wavelength selective reflection film 3 is directly formed on the window material 41.

  The window material 41 has a structure 42 on one main surface thereof. The wavelength selective reflection film 3 and the optical layer 43 are sequentially laminated on one main surface on which the structure 42 is formed. As the shape of the structure 42, a shape obtained by inverting the unevenness of the structure 11 in the first embodiment can be used. The optical layer 43 is for improving the transmission map definition and the total light transmittance, and also for protecting the wavelength selective reflection film 3. The optical layer 43 is formed, for example, by curing a resin mainly composed of a thermoplastic resin or an ionizing radiation curable resin.

<8. Eighth Embodiment>
21A and 21B are cross-sectional views illustrating a first configuration example of a directional reflector according to the eighth embodiment of the present invention. 22A and 22B are cross-sectional views showing a second configuration example of the directional reflector according to the eighth embodiment of the present invention. In the eighth embodiment, the same portions as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted. The eighth embodiment is different from the first embodiment in that at least one of the first optical layer 4 and the second optical layer 5 has a two-layer structure. 21A and 21B show an example in which the first optical layer 4 on the incident light surface S1 side of external light has a two-layer structure. 22A and 22B, there is an example in which both the first optical layer 4 on the incident light surface S1 side of external light and the second optical layer 5 on the outgoing light surface S2 side of external light have a two-layer structure. It is shown. As shown in FIGS. 21A and 21B, the two-layer structure of the first optical layer 4 is formed between, for example, a smooth base material 4a on the surface side, and the base material 4a and the wavelength selective reflection film 3. It is comprised from the resin layer 4b made. As shown in FIGS. 22A and 22B, the two-layer structure of the second optical layer 5 is formed between, for example, a smooth base material 5a on the surface side and the base material 5a and the wavelength selective reflection film 3. Resin layer 5b. Below, the 2nd optical layer 5 in which the wavelength selection reflection film 3 was formed is called the optical layer 9 with a reflection layer.

  The directional reflector 1 is bonded to, for example, the indoor side or the outdoor side of the window member 10 that is an adherend via the bonding layer 8. As the bonding layer 8, for example, an adhesive layer containing an adhesive as a main component or an adhesive layer containing an adhesive as a main component can be used. When the bonding layer 8 is an adhesive layer, as shown in FIGS. 21B and 22B, the directional reflector 1 is formed on the adhesive layer formed on the incident surface S1 or the exit surface S2, and on the adhesive layer. It is preferable to further include a released release layer. This is because the directional reflector 1 can be easily bonded to an adherend such as the window material 10 through the adhesive layer simply by peeling off the peeling layer.

  From the viewpoint of improving the adhesion between the directional reflector 1 and the bonding layer 8, it is preferable to further form a primer layer between the directional reflector 1 and the bonding layer 8. Similarly, from the viewpoint of improving the adhesiveness between the directional reflector 1 and the bonding layer 8, a known physical front surface with respect to the incident surface S <b> 1 or the exit surface S <b> 2 on which the bonding layer 8 of the directional reflector 1 is formed. It is preferable to perform the treatment. Known physical pretreatments include, for example, plasma treatment and corona treatment.

  The first substrate 4a and the second substrate 5a are, for example, substrates having transparency. Examples of the shape of the base material 51 include a film shape, a sheet shape, a plate shape, and a block shape, but are not particularly limited to these shapes. As a material of the base material 11, for example, a known polymer material can be used. Known polymer materials include, for example, triacetyl cellulose (TAC), polyester (TPEE), polyethylene terephthalate (PET), polyimide (PI), polyamide (PA), aramid, polyethylene (PE), polyacrylate, polyether Examples include sulfone, polysulfone, polypropylene (PP), diacetyl cellulose, polyvinyl chloride, acrylic resin (PMMA), polycarbonate (PC), epoxy resin, urea resin, urethane resin, melamine resin, etc. It is not limited. Although it is preferable that the thickness of the 1st base material 4a and the 2nd base material 5a is 38-100 micrometers from a viewpoint of productivity, it is not specifically limited to this range. It is preferable that the 1st base material 4a or the 2nd base material 5a has ionizing ray permeability. Thereby, as will be described later, the first substrate 4a, or the ionizing radiation curable resin interposed between the second substrate 5a or the second substrate 5a and the wavelength selective reflection film 3, the first substrate 4a, Alternatively, it is possible to irradiate ionizing rays from the second substrate 5a side and cure the ionizing ray-curable resin.

  The first resin layer 4b and the second resin layer 5b have transparency, for example. The first resin layer 4b is obtained, for example, by curing the resin composition between the first substrate 4a and the wavelength selective reflection film 3. The second resin layer 5b is obtained, for example, by curing the resin composition between the second base material 5a and the wavelength selective reflection film 3. From the viewpoint of ease of production, it is preferable to use an ionizing radiation curable resin that is cured by light or an electron beam, or a thermosetting resin that is cured by heat. As the ionizing radiation curable resin, a photosensitive resin composition curable by light is preferable, and an ultraviolet curable resin composition curable by ultraviolet light is most preferable. From the viewpoint of improving the adhesion between the first resin layer 4b or the second resin layer 5b and the wavelength selective reflection film 3, the resin composition includes a compound containing phosphoric acid, a compound containing succinic acid, and butyrolactone. It is preferable to further contain a compound containing As the compound containing phosphoric acid, for example, (meth) acrylate containing phosphoric acid, preferably a (meth) acrylic monomer or oligomer having phosphoric acid as a functional group can be used. As the compound containing succinic acid, for example, a (meth) acrylate containing succinic acid, preferably a (meth) acrylic monomer or oligomer having succinic acid as a functional group can be used. As the compound containing butyrolactone, for example, a (meth) acrylate containing butyrolactone, preferably a (meth) acryl monomer or oligomer having butyrolactone as a functional group can be used. It is preferable that at least one of the first resin layer 4b and the second resin layer 5b includes a highly polar functional group, and the content thereof is different between the first resin layer 4b and the second resin layer 5b. Both the 1st resin layer 4b and the 2nd resin layer 5b contain the compound containing phosphoric acid, and the content of the said phosphoric acid in the 1st resin layer 4b and the 2nd resin layer 5b differs. It is preferable. The phosphoric acid content in the first resin layer 4b and the second resin layer 5b is preferably 2 times or more, more preferably 5 times or more, and even more preferably 10 times or more.

When at least one of the first resin layer 4b and the second resin layer 5b includes a compound containing phosphoric acid, the wavelength selective reflection film 3 includes the first resin layer 4b or the second resin containing the compound containing phosphoric acid. The surface in contact with the second resin layer 5b preferably contains an oxide, nitride, or oxynitride.
It is particularly preferable that the wavelength selective reflection film 3 has a thin film containing zinc oxide on the surface in contact with the first resin layer 4b containing the compound containing phosphoric acid or the second resin layer 5b.

  The ultraviolet curable resin composition contains, for example, (meth) acrylate and a photopolymerization initiator. Moreover, you may make it an ultraviolet curable resin composition further contain a light stabilizer, a flame retardant, a leveling agent, antioxidant, etc. as needed.

  As the acrylate, it is preferable to use a monomer and / or an oligomer having two or more (meth) acryloyl groups. As this monomer and / or oligomer, for example, urethane (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate, polyol (meth) acrylate, polyether (meth) acrylate, melamine (meth) acrylate and the like are used. be able to. Here, the (meth) acryloyl group means either an acryloyl group or a methacryloyl group. Here, the oligomer refers to a molecule having a molecular weight of 500 or more and 60000 or less.

  As the photopolymerization initiator, those appropriately selected from known materials can be used. As a known material, for example, a benzophenone derivative, an acetophenone derivative, an anthraquinone derivative, or the like can be used alone or in combination. The blending amount of the polymerization initiator is preferably 0.1% by mass or more and 10% by mass or less in the solid content. If it is less than 0.1% by mass, the photocurability is lowered, which is substantially unsuitable for industrial production. On the other hand, when it exceeds 10 mass%, when the amount of irradiation light is small, odor tends to remain in the coating film. Here, solid content means all the components which comprise the hard-coat layer 12 after hardening. Specifically, for example, acrylate, photopolymerization initiator, and the like are referred to as solid content.

  The resin used is preferably a resin that does not deform even at the process temperature during dielectric formation and does not generate cracks. If the glass transition temperature is low, it is not preferable since it is deformed at a high temperature after installation or the resin shape is changed at the time of forming the dielectric, and if the glass transition temperature is high, cracks and interface peeling are likely to occur. Specifically, the glass transition temperature is preferably 60 ° C. or higher and 150 ° C. or lower, and more preferably 80 ° C. or higher and 130 ° C. or lower.

  The resin is preferably one that can transfer the structure by irradiation with energy rays or heat, and any type of resin can be used as long as it satisfies the above refractive index requirements, such as vinyl resin, epoxy resin, and thermoplastic resin. May be.

  An oligomer may be added so that curing shrinkage is small. Polyisocyanate or the like may be included as a curing agent. In consideration of adhesion to the base material, coupling agents such as monomers having a hydroxyl group, carboxyl group, carboxylic acid, and phosphate group, polyhydric alcohols, silane, aluminum, titanium, and various chelating agents Etc. may be added.

  As the vinyl resin, an acrylic (meth) resin is preferable, and as a preferred acrylic (meth) resin, specific examples of the hydroxyl group-containing vinyl monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl ( (Meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) ) Acrylate, di-2-hydroxyethyl fumarate or mono-2-hydroxyethyl-monobutyl fumarate, polyethylene glycol- or polypropylene glycol mono (meth) acrylate or an adduct of these with ε-caprolactone, Plastic [Manufactured by Daicel Chemical Co., trade name of caprolactone addition monomer] cell FM or FA Monomer "such as various alpha, hydroxyalkyl esters of β- ethylenically unsaturated carboxylic acid, and the like.

  Specific examples of the carboxyl group-containing vinyl monomer include various unsaturated mono- or dicarboxylic acids or monoethyl fumarate such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid or citraconic acid. Dicarboxylic acid monoesters such as monobutyl maleate, or the above-mentioned hydroxyl group-containing (meth) acrylates and succinic acid, maleic acid, phthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, benzenetricarboxylic acid, benzenetetracarboxylic Examples include acids, “hymic acids”, adducts of various polycarboxylic acids such as tetrachlorophthalic acid with anhydrides, and the like.

  Specific examples of the phosphoric acid group-containing vinyl monomer include dialkyl [(meth) acryloyloxyalkyl] phosphates or (meth) acryloyloxyalkyl acid phosphates, dialkyl [(meth) acryloyloxyalkyl] phosphites or (Meth) acryloyloxyalkyl acid phosphites are mentioned.

  Examples of polyhydric alcohols include ethylene glycol, propylene glycol, glycerin, trimethylol ethane, trimethylol propane, neopentyl glycol, 1,6-hexanediol, 1,2,6-hexanetriol, pentaerythritol or sorbitol, One type or two or more types of various polyhydric alcohols can be used. Further, although not alcohol, various fatty acid glycidyl esters such as “Cardura E” (trade name of fatty acid glycidyl ester, manufactured by Shell of the Netherlands) can be used instead of alcohol.

  Carboxylic acids include benzoic acid, p-tert-butylbenzoic acid, (anhydrous) phthalic acid, hexahydro (anhydrous) phthalic acid, tetrahydro (anhydrous) phthalic acid, tetrachloro (anhydrous) phthalic acid, hexachloro (anhydrous) phthalic acid , Tetrabromo (anhydride) phthalic acid, trimellitic acid, "Himic acid" [product of Hitachi Chemical Co., Ltd .; "Himic acid" is a registered trademark of the company. ],

Various carboxylic acids such as (anhydrous) succinic acid, (anhydrous) maleic acid, fumaric acid, (anhydrous) itaconic acid, adipic acid, sebacic acid or oxalic acid can be used. These monomers may be used alone or may be copolymerized, and examples thereof include monomers that can be copolymerized. Styrene monomers such as styrene, vinyl toluene, p-methyl styrene, ethyl styrene, propyl styrene, isopropyl styrene or p-tert-butyl styrene.
Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, iso (i) -propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, tert-butyl (meta ) Acrylate, sec-butyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate or lauryl (meth) acrylate, “Acryester SL” [C12- / C13 methacrylate, manufactured by Mitsubishi Rayon Co., Ltd. Trade name of the mixture], alkyl (meth) acrylates such as stearyl (meth) acrylate; cyclohexyl (meth) acrylate, 4-tert-butylcyclohexyl (meth) acrylate or isobornyl (meth) acrylate, Adamantyl (meth) acrylate, containing no functional groups, such as the side chain benzyl (meth) acrylate (meth) acrylate; and ethylene - di - (meth) bifunctional vinyl monomers such as acrylates.

  Various alkoxyalkyl (meth) acrylates such as methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate or methoxybutyl (meth) acrylate.

  Various dicarboxylic acids represented by maleic acid, fumaric acid or itaconic acid, such as dimethyl maleate, diethyl maleate, diethyl fumarate, di (n-butyl) fumarate, di (i-butyl) fumarate or dibutyl itaconate And diesters of monohydric alcohols.

  Various vinyl esters such as vinyl acetate, vinyl benzoate, or “Beoba” (trade name of vinyl esters of branched (branched) aliphatic monocarboxylic acids, manufactured by Shell of the Netherlands), (meth) acrylonitrile, etc. .

N, N-alkylaminoalkyl (meth) acrylates such as N-dimethylaminoethyl (meth) acrylate and N, N-diethylaminoethyl (meth) acrylate; and (meth) acrylamide, N-methylol (meth) Nitrogen-containing vinyl monomers such as amide bond-containing vinyl monomers such as butyl ether of acrylamide and dimethylaminopropyl acrylamide.
The amount of these can be arbitrarily adjusted according to the properties of the dielectric layer and the metal film.

The first base material 4a or the second base material 5a preferably has a lower water vapor transmission rate than the first resin layer 4b or the second resin layer 5b. For example, when the first resin layer 4b is formed of an ionizing radiation curable resin such as urethane acrylate, the first substrate 4a has a lower water vapor transmission rate than the first resin layer 4b, and is capable of transmitting ionizing radiation. It is preferable to form with a resin such as polyethylene terephthalate (PET). Thereby, the diffusion of moisture from the incident surface S1 or the exit surface S2 to the wavelength selective reflection film 3 can be reduced, and deterioration of the metal or the like contained in the wavelength selective reflection film 3 can be suppressed. Therefore, the durability of the directional reflector 1 can be improved. The water vapor transmission rate of PET is about 50 g / m ² · day (40 ° C., 90% RH).

[Directional reflector manufacturing equipment]
FIG. 23 is a schematic diagram illustrating a configuration example of a directional reflector manufacturing apparatus according to the eighth embodiment of the present invention. As shown in FIG. 23, this manufacturing apparatus includes a base material supply roll 51, an optical layer supply roll 52, a take-up roll 53, laminate rolls 54 and 55, guide rolls 56 to 60, a coating apparatus 61, and an irradiation apparatus 62. Prepare.

  The base material supply roll 51 and the optical layer supply roll 52 are each formed by rolling a belt-like base material 4a and a belt-like optical layer 9 with a reflective film, and the base material 4a and the optical layer with a reflective film by rollers 56, 57, etc. 9 is arranged so that it can be sent out continuously. The arrow in the figure indicates the direction in which the substrate 4a and the optical layer 9 with a reflective film are conveyed. The optical layer 9 with a reflective film is the second optical layer 5 on which the wavelength selective reflective film 3 is formed.

  The take-up roll 53 is arranged so that the strip-shaped directional reflector 1 produced by this manufacturing apparatus can be taken up. The laminate rolls 54 and 55 are arranged so that the optical layer 9 with a reflective film sent from the optical layer supply roll 52 and the base material 4a sent from the base material supply roll 51 can be nipped. The guide rolls 56 to 60 are arranged on a transport path in the manufacturing apparatus so that the strip-shaped optical layer 9 with a reflective film, the strip-shaped base material 4a, and the strip-shaped directional reflector 1 can be transported. The materials of the laminate rolls 54 and 55 and the guide rolls 56 to 60 are not particularly limited, and a metal such as stainless steel, rubber, silicone, or the like can be appropriately selected and used according to desired roll characteristics.

  As the coating device 61, for example, a device including coating means such as a coater can be used. As the coater, for example, a coater such as a gravure, a wire bar, and a die can be appropriately used in consideration of physical properties of the resin composition to be applied. The irradiation device 62 is an irradiation device that irradiates an ionizing ray such as an electron beam, an ultraviolet ray, a visible ray, or a gamma ray.

[Manufacturing method of directional reflector]
Hereinafter, an example of a method for manufacturing a directional reflector according to the eighth embodiment of the present invention will be described with reference to FIGS. 22 and 23.

  First, the optical layer 9 with a reflective film is produced as follows. That is, an ionizing ray curable resin is applied onto the belt-shaped substrate 5a, and the uneven surface of the mold such as a roll shape is pressed against the applied ionizing ray curable resin, and the ionizing ray curable resin is applied from the substrate 5a side. On the other hand, ionizing radiation is irradiated to cure the ionizing radiation curable resin. Thereby, the 2nd optical layer 5 which has an uneven surface is formed. Next, the wavelength selective reflection film 3 is formed on the uneven surface of the second optical layer 5 by, for example, sputtering. Thereby, the optical layer 9 with a reflecting film is produced. As a method for forming the wavelength selective reflection film 3, at least one of a physical vapor deposition method and a chemical vapor deposition method can be used, and a sputtering method is preferably used. Next, the optical layer 9 with a reflective film is wound around the optical layer supply roll 52.

Next, using the manufacturing apparatus shown in FIG. 23, the directional reflector 1 is manufactured as follows.
First, the base material 4 a is sent from the base material supply roll 51, and the sent base material 4 a passes under the coating device 61 through the guide roll 56. Next, the ionizing radiation curable resin is applied by the coating device 61 onto the base material 4 a that passes under the coating device 61. Next, the base material 4a coated with the ionizing radiation curable resin is conveyed toward the laminate roll. On the other hand, the optical layer 9 with a reflecting film is sent out from the optical layer supply roll 52 and conveyed toward the laminating rolls 54 and 55 through the guide roll 57.

  Next, the carried-in base material 4a and the optical layer 9 with a reflecting film are sandwiched between the laminate rolls 54 and 55 so that air bubbles do not enter between the base material 4a and the optical layer 9 with a reflecting film. The optical layer 9 with a reflective film is laminated on 4a. Next, the substrate 4a laminated by the optical layer 9 with the reflective film is conveyed along the outer peripheral surface of the laminate roll 55, and the ionizing radiation curable resin is irradiated from the substrate 4a side by the irradiation device 62. Then, the ionizing radiation curable resin is cured. Thereby, the base material 4a and the optical layer 9 with a reflecting film are bonded together via ionizing-ray cured resin, and the target directional reflector 1 is produced. Next, the produced band-shaped directional reflector 1 is conveyed to the take-up roll 53 via the rolls 58, 59, 60, and the directional reflector 1 is taken up by the take-up roll 53.

<9. Ninth Embodiment>
FIG. 24 is a cross-sectional view showing a first configuration example of a directional reflector according to the ninth embodiment of the present invention. FIG. 25 is a cross-sectional view showing a second configuration example of the directional reflector according to the ninth embodiment of the present invention. The ninth embodiment further includes a barrier layer 71 on the entrance surface S1 or the exit surface S2 bonded to the adherend such as the window member 10 or between the surface and the wavelength selective reflection film 3. However, this is different from the eighth embodiment. FIG. 24 shows an example in which the directional reflector 1 further includes a barrier layer 71 on the incident surface S1 bonded to an adherend such as the window material 10. FIG. 25 shows an example in which the directional reflector 1 further includes a barrier layer 71 between the first base material 4a and the resin layer 4b on the side to which the adherend such as the window material 10 is attached. Yes.

Examples of the material of the barrier layer 71 include inorganic oxides including at least one of alumina (Al ₂ O ₃ ), silica (SiO _x ), and zirconia, polyvinylidene chloride (PVDC), polyvinyl fluoride resin, and ethylene. A resin material containing at least one kind of a partially hydrolyzed product (EVOH) of a vinyl acetate copolymer can be used. The material of the barrier layer 71, for _{example, SiN, ZnS-SiO 2,} AlN, Al 2 O 3, SiO 2 -Cr 2 O 3 composite oxide of _{-ZrO 2 (SCZ), SiO 2} -In 2 A dielectric material containing at least one of complex oxide (SIZ) composed of O ₃ —ZrO ₂ , TiO ₂ , and Nb ₂ O ₅ can also be used.

  As described above, when the directional reflector 1 further includes the barrier layer 71 on the incident surface S1 or the exit surface S2, the first optical layer 4 or the second optical layer 5 on which the barrier layer 71 is formed is provided. It is preferable to have the following relationship. That is, it is preferable that the water vapor permeability of the first base material 4a or the second base material 5a on which the barrier layer 71 is formed is lower than that of the first resin layer 4b or the second resin layer 5b. . This is because moisture diffusion from the incident surface S1 or the exit surface S2 of the directional reflector 1 to the wavelength selective reflection film 3 can be further reduced.

  In the ninth embodiment, since the directional reflector 1 further includes the barrier layer 71 on the incident surface S1 or the output surface S2, the diffusion of moisture from the incident surface S1 or the output surface S2 to the wavelength selective reflection film 3 is reduced, It is possible to suppress deterioration of the metal contained in the wavelength selective reflection film 3. Therefore, the durability of the directional reflector 1 can be improved.

<10. Tenth Embodiment>
FIG. 26 is a cross-sectional view showing a configuration example of a directional reflector according to the tenth embodiment of the present invention. In the tenth embodiment, the same portions as those in the eighth embodiment are denoted by the same reference numerals, and description thereof is omitted. The tenth embodiment is different from the eighth embodiment in that it further includes a hard coat layer 72 formed on at least one of the entrance surface S1 and the exit surface S2 of the directional reflector 1. FIG. 26 shows an example in which a hard coat layer 72 is formed on the exit surface S2 of the directional reflector 1.

  The pencil hardness of the hard coat layer 72 is preferably 2H or more, more preferably 3H or more, from the viewpoint of scratch resistance. The hard coat layer 72 is obtained by applying and curing a resin composition on at least one of the entrance surface S1 and the exit surface S2 of the directional reflector 1. Examples of the resin composition include Japanese Patent Publication No. 50-28092, Japanese Patent Publication No. 50-28446, Japanese Patent Publication No. 51-24368, Japanese Patent Publication No. 52-112698, Japanese Patent Publication No. 57-2735, Examples disclosed in JP-A No. 2001-301095 include, for example, organosilane thermosetting resins such as methyltriethoxysilane and phenyltriethoxysilane, and melamine heat such as etherified methylolmelamine. Examples thereof include polyfunctional acrylate-based ultraviolet curable resins such as curable resins, polyol acrylates, polyester acrylates, urethane acrylates, and epoxy acrylates.

  From the viewpoint of imparting antifouling properties to the hard coat layer 72, the resin composition preferably further contains an antifouling agent. As the antifouling agent, it is preferable to use a silicone oligomer and / or a fluorine-containing oligomer having one or more (meth) acryl groups, vinyl groups, or epoxy groups. It is preferable that the compounding quantity of a silicone oligomer and / or a fluorine oligomer is 0.01 to 5 mass% of solid content. If it is less than 0.01% by mass, the antifouling function tends to be insufficient. On the other hand, when it exceeds 5 mass%, there exists a tendency for coating-film hardness to fall. Examples of the antifouling agent include RS-602 and RS-751-K manufactured by DIC Corporation, CN4000 manufactured by Sartomer, Optool DAC-HP manufactured by Daikin Industries, Ltd., and X-22 manufactured by Shin-Etsu Chemical Co., Ltd. It is preferable to use -164E, FM-7725 manufactured by Chisso Corporation, EBECRYL350 manufactured by Daicel-Cytec Corporation, TEGORad2700 manufactured by Degussa Corporation, and the like. The pure contact angle of the hard coat layer 72 to which the antifouling property is imparted is preferably 70 ° or more, more preferably 90 ° or more. The resin composition may further contain additives such as a light stabilizer, a flame retardant, and an antioxidant as necessary.

  According to the tenth embodiment, since the hard coat layer 72 is formed on at least one of the incident surface S1 and the exit surface S2 of the directional reflector 1, the directional reflector 1 is given scratch resistance. Can do. For example, when the directional reflector 1 is bonded to the inside of the window, the generation of scratches is suppressed even when a person touches the surface of the directional reflector 1 or the surface of the directional reflector 1 is cleaned. Can do. Moreover, also when the directional reflector 1 is bonded to the outside of the window, the generation of scratches can be similarly suppressed.

<11. Eleventh Embodiment>
FIG. 27 is a cross-sectional view showing a configuration example of a directional reflector according to the eleventh embodiment of the present invention. In the eleventh embodiment, the same portions as those in the tenth embodiment are denoted by the same reference numerals and description thereof is omitted. The eleventh embodiment is different from the tenth embodiment in that an antifouling layer 74 is further provided on the hard coat layer 72. From the viewpoint of improving the adhesion between the hard coat layer 72 and the antifouling layer 74, a coupling agent layer (primer layer) 73 is further provided between the hard coat layer 72 and the antifouling layer 74. It is preferable.

  In the eleventh embodiment, since the directional reflector 1 further includes the antifouling layer 74 on the hard coat layer 72, the antifouling property can be imparted to the directional reflector 1.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited only to these Examples.

Example 1
First, as shown in FIG. 28, a prism shape was applied to a Ni-P mold by cutting with a cutting tool. Next, a mixed resin of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name DPHA) is applied to the Ni-P mold, and PET having a thickness of 75 μm is further applied thereon. A film (manufactured by Toyobo, A4300) was placed. Next, after UV light was irradiated to the mixed resin from the PET film side to cure the mixed resin, the adhesive body of the resin and the PET film was peeled from the mold.

  Next, the laminate of the resin and PET was peeled off from the Ni-P mold to obtain a resin layer (second optical layer) having a prism-shaped molding surface. Next, as shown in Table 1 below, an alternating multilayer film of a niobium pentoxide film and a silver film was formed by vacuum sputtering on the molding surface having a prism shape formed by a mold. Next, the spectral reflectance of the PET film with alternating multilayer films was measured with a DUV3700 manufactured by Shimadzu Corporation. As a result, the spectral reflectance curve shown in FIG. 29 was obtained. Next, after applying the above-mentioned mixed resin again on the alternate multilayer film and extruding bubbles, the PET film is placed and UV light irradiation is applied to cure the resin, and the resin layer ( 1st optical layer) was formed. Thereby, the optical film which is the target directional reflector was obtained.

(Example 2)
First, as shown in FIGS. 30A and 30B, a triangular pyramid shape was imparted to a Ni-P mold by cutting with a cutting tool. Next, urethane acrylate (Toagosei Co., Ltd., Aronix, post-curing refractive index 1.533) is applied to the Ni-P mold, and a 75 μm thick PET film (Toyobo Co., A4300) is installed on the Ni-P mold. Then, the resin was cured by irradiating UV light from the PET film side.

  Next, after peeling the laminate of the resin and PET from the Ni-P mold, the zinc oxide film and the silver alloy are formed on the molding surface having a triangular pyramid shape formed by the mold as shown in Table 1. An alternating multilayer film was formed by vacuum sputtering. In addition, the alloy target which has a composition of Ag / Nd / Cu = 99.0 at% / 0.4 at% / 0.6 at% was used for film-forming of the AgNdCu film | membrane which is a silver alloy film. After film formation, the same resin as the underlayer (Toagosei Co., Ltd., Aronix, refractive index after curing 1.533) was applied onto the shape surface on which the alternating multilayer film was formed. Further, a 75 μm-thick PET film (A4300, manufactured by Toyobo Co., Ltd.) was placed thereon, and after extruding bubbles, UV light was irradiated through the PET film to cure the resin.

(Example 3)
An optical film of Example 3 was obtained in the same manner as in Example 2 except that the selective reflection film had a film thickness configuration shown in Table 1.

Example 4
An optical film of Example 4 was obtained in the same manner as Example 2 except that the selective reflection film had a film thickness configuration shown in Table 1.

(Example 5)
As in Example 2, after forming a triangular pyramid shape using a resin having a refractive index after curing of 1.533, selective recursion by an alternating multilayer film of a zinc oxide film and a silver alloy film with the same configuration as in Example 2 A reflective film was formed. Thereafter, a UV curable resin (manufactured by Toagosei Co., Ltd., Aronix, refractive index after curing 1.540) was applied on the shape surface on which the alternating multilayer film was formed. Further, a 75 μm-thick PET film (A4300, manufactured by Toyobo Co., Ltd.) was placed thereon, and after extruding bubbles, UV light was irradiated through the PET film to cure the resin. Thus, an optical film of Example 5 having a refractive index difference of 0.007 between the upper layer resin and the lower layer resin was obtained.

(Example 6)
An optical film of Example 6 was obtained in the same manner as in Example 5 except that a UV curable resin having a refractive index of 1.542 after curing was used for the upper layer, and the difference in refractive index between the upper resin and the lower resin was 0.009. .

(Comparative Example 1)
On the PET film having a smooth surface, an alternating multilayer film having a film thickness configuration shown in Table 1 was formed to obtain an optical film of Comparative Example 1.

(Comparative Example 2)
An alternating multilayer film was formed on a PET film having a smooth surface under the same film forming conditions as in Example 2 to obtain an optical film of Comparative Example 2.

(Comparative Example 3)
An alternating multilayer film was formed on a PET film having a smooth surface under the same film forming conditions as in Example 3 to obtain an optical film of Comparative Example 3.

(Comparative Example 4)
On the PET film having a smooth surface, an alternating multilayer film was formed under the same film forming conditions as in Example 4 to obtain an optical film of Comparative Example 4.

(Comparative Example 5)
In the same manner as in Example 2 until the step of forming the alternating multilayer film, a PET film with an alternating multilayer film was obtained, and then the alternating multilayer film was exposed without being filled with the resin. Comparative Example 5 An optical film was obtained.

(Comparative Example 6)
Up to the formation process of the alternating multilayer film, a PET film with an alternating multilayer film was obtained in the same manner as in Example 2, and then the same resin as the underlayer (Aronix, manufactured by Toagosei Co., Ltd.) was formed on the shape surface on which the alternating multilayer film was formed. After curing, a refractive index of 1.533) was applied. Next, in order to avoid curing inhibition due to oxygen without covering the applied resin with a PET film, the resin was cured by irradiation with UV light under N ₂ purge. This obtained the optical film of the comparative example 6.

(Comparative Example 7)
An optical film of Comparative Example 7 was obtained in the same manner as in Example 5 except that a UV curable resin having a refractive index of 1.546 after curing was used for the upper layer, and the difference in refractive index between the upper resin and the lower resin was 0.013. .

(Comparative Example 8)
An optical film of Comparative Example 8 was obtained in the same manner as in Example 5 except that a UV curable resin having a refractive index of 1.558 after curing was used for the upper layer, and the refractive index difference between the upper layer resin and the lower layer resin was 0.025. .

(Evaluation of directional reflectance)
The directional reflectances of the optical films of Example 1 and Comparative Example 1 were evaluated as follows.
FIG. 31 shows the configuration of a measuring apparatus for measuring the retroreflectance of the optical film. The linear light emitted from the halogen lamp light source 101 and collimated by the lens is incident on the half mirror 102 installed at an angle of 45 ° with respect to the traveling direction of the light. Half of the incident light is reflected by the half mirror 102 and its traveling direction is rotated by 90 °, while the other half of the incident light is transmitted through the half mirror 102. Next, the reflected light is retroreflected by the sample 103 and enters the half mirror 102 again. Half of this incident light passes through the half mirror 102 and enters the detector 104. The intensity of this incident light is measured by the detector 104 as the reflection intensity.

  Using the measuring apparatus having the above-described configuration, the retroreflectance at wavelengths of 900 nm and 1100 nm was determined by the following method. First, a mirror was installed in the sample folder of this measuring apparatus at an incident angle θ = 0 °, and the light intensity of each wavelength was measured by the detector 104. Next, an optical film was installed in the sample folder of this measuring apparatus, and the light intensity was measured at incident angles θ = 0 °, 20 °, 40 °, 60 °, and 80 °. Thereafter, the retroreflectance of the optical film was determined with the light intensity of the mirror as 90% retroreflectance. The results are shown in Table 2 (in this measurement, φ = 0 °).

(Evaluation of directional reflection direction)
Evaluation of the directional reflection direction of the optical films of Examples 1 to 6 and Comparative Examples 5 to 8 was performed as follows using the measurement apparatus shown in FIG. With the sample 103 as the central axis, the detector 104 was rotated as indicated by the arrow a, and the direction in which the reflection intensity was maximum was measured. The results are shown in Table 3.

(Evaluation of vertical transmittance)
The vertical transmittances of the optical films of Examples 2 to 4 and Comparative Examples 2 to 4 were evaluated as follows.
The vertical transmittance in the visible and near-infrared region was measured with DUV3700 manufactured by Shimadzu Corporation. The spectral transmittance waveform is shown in FIG. 32 and FIG.

(Evaluation of chromaticity)
The chromaticities of the optical films of Examples 2 to 4 and Comparative Examples 2 to 4 were evaluated as follows.
In order to suppress the influence of the color of the back surface, the optical films of Examples and Comparative Examples were placed on a black plate (Mitsubishi Rayon Acrylite L502) and SP62 (xRite Integrating Sphere Colorimeter. D / 8 °. Measurement was performed with an optical system, a D64 light source, a 2 ° field of view, and a SPEX mode. The results are shown in Table 4. The chromaticity of the black plate measured without placing a sample was x = 0.325 and y = 0.346.

(Evaluation of transmitted map definition)
The transmitted image clarity of the optical films of Examples 1 to 5 and Comparative Examples 5 to 8 were evaluated as follows. In accordance with JIS-K7105, transmission map definition was evaluated using optical combs having a comb width of 2.0 mm, 1.0 mm, 0.5 mm, and 0.125 mm. The measuring device used for the evaluation is an image clarity measuring device (ICM-1T type) manufactured by Suga Test Instruments Co., Ltd. Next, the sum total of the transmitted map clarity measured using optical combs having a comb width of 2.0 mm, 1.0 mm, 0.5 mm, and 0.125 mm was obtained. The results are shown in Table 3.

(Evaluation of haze)
The haze evaluation of the optical films of Examples 1 to 6 and Comparative Examples 5 to 8 was evaluated as follows.
Based on the measurement conditions based on JIS K7136, the haze was measured using a haze meter HM-150 (manufactured by Murakami Color Research Laboratory). The results are shown in Table 3. The light source was a D65 light source, and measurement was performed without applying a filter.

(Visibility evaluation)
The visibility of the optical films of Examples 1 to 6 and Comparative Examples 5 to 8 was evaluated as follows.
The produced film was bonded to 3 mm thick glass with an optically transparent adhesive. Next, this glass was held about 50 cm away from the eyes, and the inside of an adjacent building at a distance of about 10 m was observed through the glass and evaluated according to the following criteria. The results are shown in Table 3.
◎: Multiple images due to diffraction are not seen, and looks like a normal window ○: There is no problem in normal use, but if there is a specular reflector etc., multiple images due to diffraction are slightly visible △: Approximate object The shape can be distinguished, but I'm worried about multiple images due to diffraction. ×: I don't know what is cloudy due to the influence of diffraction.

(Measurement of surface roughness)
The surface roughness of the optical film of Comparative Example 6 was evaluated as follows.
The surface roughness was measured using a stylus type surface shape measuring instrument ET-4000 (manufactured by Kosaka Laboratory). The result is shown in FIG.

Table 1 shows the structure of the optical film of Examples 1-6 and Comparative Examples 1-8.

Table 2 shows the evaluation results of the directional reflectance of Example 1 and Comparative Example 1.

Table 3 shows the directional reflection direction and transmission when light is incident on the optical films of Examples 1 to 6 and Comparative Examples 5 to 8 at an incident angle (θ, φ) = (10 °, 45 °). The evaluation results of map definition, haze, and visibility are shown.

Table 4 shows the chromaticity evaluation results of Examples 2 to 4 and Comparative Examples 2 to 4.

The following can be understood from Table 2 and FIG.
In the optical film of Example 1, near infrared rays can be directionally reflected while maintaining the transmittance of visible light at 80% or more. On the other hand, the optical film of Comparative Example 1 can make the visible light transmittance as high as that of Example 1, but it cannot retroreflect near-infrared rays except at an incident angle of 0 degree.

The following can be understood from Table 3 and FIG.
In the optical film of Comparative Example 5, directional reflectivity is obtained with respect to near infrared rays having a wavelength of about 1200 nm and visible light is transmitted, but resin layers are formed on the alternating multilayer film and are not transparentized. The object on the opposite side cannot be visually recognized through the optical film. In the optical film of Comparative Example 6, as shown in FIG. 34, the surface cannot be completely flattened during the clearing treatment. For this reason, in the optical film of Comparative Example 6, as in Comparative Example 5, the object on the opposite side cannot be visually recognized through the optical film. Since the maximum height Rz is about 1.3 μm and the arithmetic average roughness Ra is about 0.14 μm with respect to the pitch of the base of the triangular pyramid of about 110 μm, a smoother surface is required to make the transmitted image clear. Is necessary.
Further, in the optical films of Comparative Examples 7 and 8, the refractive index differences are 0.013 and 0.025, respectively, so that the transmission map sharpness measured using an optical comb having a width of 0.5 mm is less than 50. Yes. Further, the total value of the mapping definition values measured using optical combs of 0.125 mm, 0.5 mm, 1.0 mm, and 2.0 mm is less than 230. Therefore, in the optical films of Comparative Examples 7 and 8, the scattered light increases and the selective permeability of visible light decreases. That is, the transparency of the optical film is lowered.

Table 3 shows the following.
In the optical films of Examples 1 to 6, the mapping definition measured using an optical comb having a width of 0.5 mm is 50 or more, and the total value of mapping definition measured using each optical comb is 230 or more. It is. The visibility evaluation result is “◯” or “◎”.
On the other hand, in the optical films of Comparative Examples 5 to 8, the image clarity measured using an optical comb having a width of 0.5 mm is less than 50, and the values of the map clarity measured using each optical comb are The total value is less than 230. The visibility evaluation result is “x”.
From the above, from the viewpoint of visibility, it is preferable that the transmission map definition measured using an optical comb having a width of 0.5 mm is 50 or more. Further, from the viewpoint of visibility, it is preferable that the total value of the mapping definition values measured using optical combs of 0.125 mm, 0.5 mm, 1.0 mm, and 2.0 mm is 230 or more.

Table 3, Table 4, FIG. 32, and FIG. 33 show the following.
The optical film of Comparative Example 2 exhibits a golden tone with high reflectance in the visible light region. The optical film of Comparative Example 3 exhibits a color tone with high reflectivity and bluish green in the visible light region. The optical film of Comparative Example 4 exhibits a reddish color tone with high reflectance in the visible light region. Moreover, the color of the optical film of Comparative Examples 3-4 also changes with viewing angles. That is, the color tone of the optical films of Comparative Examples 2 to 4 is difficult to apply to a building window or the like. On the other hand, the optical films of Examples 2 to 4 having the same film configuration as Comparative Examples 2 to 4, respectively, have a hue that is not noticeable when viewed, Example 2 is slightly green, Example 3, No. 4 is slightly bluish, but the hue hardly changes even when the viewing angle is changed. Such characteristics are preferable when an optical film is applied to a window glass or the like for which designability is required.

(Example 7)
First, a Ni-P die roll having a fine triangular pyramid shape shown in FIGS. 35A and 35B was produced by cutting with a cutting tool. Next, a urethane acrylate (manufactured by Toagosei Co., Ltd., Aronix, refractive index 1.533 after curing) is applied onto a 75 μm thick PET film (A4300, manufactured by Toyobo Co., Ltd.), and UV is applied from the PET film side in a state of being in close contact with the mold. The urethane acrylate was cured by irradiation with light. Next, the laminate of the resin layer obtained by curing urethane acrylate and the PET film was peeled from the Ni-P mold. Thereby, a resin layer (hereinafter referred to as a shape resin layer) provided with a triangular pyramid shape was formed on the PET film. Next, a wavelength selective reflection film having a film configuration shown in Table 5 was formed by sputtering on a molding surface having a triangular pyramid shape formed by a mold. An alloy target having a composition of Ag / Pd / Cu = 99.0 at% / 0.4 at% / 0.6 at% was used for forming the AgPdCu film.

  Next, using the manufacturing apparatus shown in FIG. 23, the film formation surface of the shaped film was embedded with resin as follows. That is, a resin composition having the following composition is applied onto a 75 μm-thick smooth PET film (Toyobo, A4300), and a wavelength selective reflection film is formed on the surface so that air bubbles do not enter between the two films. A smooth PET film was laminated with a PET film. Thereafter, the resin composition was cured by irradiating UV light from the smooth PET film side. Thereby, the resin composition between the smooth PET film and the wavelength selective reflection film was cured, and a resin layer (hereinafter referred to as an embedded resin layer) was formed. Thus, the objective optical film of Example 7 was obtained.

<Formulation of resin composition>
99 parts by mass of urethane acrylate (manufactured by Toagosei, Aronix, refractive index after curing 1.533)
2-acryloyloxyethyl acid phosphate 1 part by mass (Kyoei Chemical Co., Ltd., light acrylate P-1A)

(Example 8)
An optical film of Example 8 was obtained in the same manner as Example 7 except that the wavelength selective reflection film was changed to the film configuration shown in Table 5.

Example 9
An optical film of Example 9 was obtained in the same manner as Example 7 except that the wavelength selective reflection film was changed to the film configuration shown in Table 5. An alloy target having a composition of Ag / Bi = 99.0 at% / 1.0 at% is used for forming the AgBi film, and an Nb ₂ O ₅ ceramic target is used for forming the Nb ₂ O ₅ film. Was used.

(Example 10)
An optical film of Example 10 was obtained in the same manner as in Example 9, except that the wavelength selective reflection film had the film configuration shown in Table 5.

(Example 11)
An optical film of Example 11 was obtained in the same manner as in Example 9 except that the wavelength selective reflection film had the film configuration shown in Table 5.

(Example 12)
An optical film of Example 12 was obtained in the same manner as Example 9 except that the wavelength selective reflection film was changed to the film configuration shown in Table 5.

(Comparative Example 9)
The optical film of Comparative Example 9 was prepared in the same manner as in Comparative Example 1 except that a wavelength selective reflection film having the same configuration as that of Example 7 was formed on a PET film having a smooth surface instead of the shaped PET film. Obtained.

(Comparative Example 10)
The optical film of Comparative Example 10 was prepared in the same manner as in Comparative Example 1 except that a wavelength selective reflection film having the same configuration as that of Example 8 was formed on a PET film having a smooth surface instead of the shaped PET film. Obtained.

(Comparative Example 11)
The optical film of Comparative Example 11 was prepared in the same manner as in Comparative Example 1 except that a wavelength selective reflection film having the same configuration as that of Example 9 was formed on a PET film having a smooth surface instead of the shaped PET film. Obtained.

(Comparative Example 12)
The optical film of Comparative Example 12 was prepared in the same manner as Comparative Example 1 except that a wavelength selective reflection film having the same configuration as Example 10 was formed on a PET film having a smooth surface instead of the shaped PET film. Obtained.

(Comparative Example 13)
The optical film of Comparative Example 13 was prepared in the same manner as in Comparative Example 1 except that a wavelength selective reflection film having the same configuration as that of Example 12 was formed on a PET film having a smooth surface instead of the shaped PET film. Obtained.

(Reflective film adhesion evaluation)
The produced film was bonded to 3 mm-thick glass with an optically transparent adhesive, and the film was peeled off to observe the state.
◎: Peeling is difficult, and if it is forcibly removed, bulk destruction of the substrate or resin occurs. ○: Peeling is relatively difficult, but if it is forcibly removed, peeling occurs at the interface. Δ: Peeling occurs at the interface. However, I feel resistance when peeling ×: Interfacial peeling occurs without resistance

(Transmittance / Reflectance evaluation)
The transmittance and reflectance of the D65 light source were measured with a spectroscopic color meter CM-3600d manufactured by Konica Minolta. The transmittance is 0 ° with respect to the perpendicular of the optical film, and the reflectance is 8 ° with respect to the perpendicular of the optical film. The results are shown in FIGS.

(Color evaluation of transmitted light / reflected light)
The transmitted color coordinates and the reflected color coordinates in the D65 light source were measured with a spectroscopic color meter CM-3600d manufactured by Konica Minolta. Further, the redness of transmitted light and reflected light was determined visually. The results are shown in Tables 6 and 7.

Table 5 shows the structures of the optical films of Examples 7 to 12 and Comparative Examples 9 to 13 and the evaluation results thereof.

Note that the film thickness in Table 5 is not the film thickness t1 in the n1 direction but the film thickness t2 in the n2 direction, as shown in FIG. However, the n1 direction and the n2 direction indicate the following directions.
n1 direction: a direction perpendicular to the inclined surface of the prism shape applied to the PET film n2 direction: a direction perpendicular to the main surface of the PET film (the thickness direction of the PET film)

Table 6 shows the evaluation results of the optical films of Examples 7 to 10 and 12.

Table 7 shows the evaluation results of the optical films of Comparative Examples 9-13.

FIG. 41 is a graph showing the sensitivity coefficient according to the test method of JIS R 3106.
In order to improve the visible light transmittance, it is necessary to have a high transmittance at a wavelength of about 500 nm where the visible visibility coefficient is high, and it is desirable to pass light of 400 to 750 nm. On the other hand, in order to increase heat shielding, it is necessary to block light in a wavelength region having a high sensitivity coefficient for shielding. In view of these, in order to improve visible transmittance and improve heat shielding, it is necessary to transmit visible light having a wavelength of about 400 to 750 nm and effectively block near infrared light having a wavelength of about 750 to 1300 nm. .

  It is preferable that the shape resin layer formed before the formation of the wavelength selective reflection film and the embedding resin layer formed after the formation of the wavelength selective reflection film have substantially the same refractive index. However, when the same resin is used for both layers, an additive is added to the embedded resin layer in order to improve the adhesion between the wavelength selective reflection film that is an inorganic thin film and the embedded resin layer that is an organic resin layer. In the shape transfer, it becomes difficult to peel the shape resin layer from the Ni-P type. When the wavelength selective reflection film is formed by a sputtering method, high energy particles adhere to it, so that the adhesion between the shape resin layer and the wavelength selective reflection film is rarely a problem. Therefore, it is preferable to suppress the amount of additive of the shape resin layer to the minimum necessary and introduce an additive that improves the adhesion to the embedded resin layer. At this time, if the refractive index of the embedding resin layer and the shape resin layer are greatly different, it is cloudy and it is difficult to see the opposite side. In Examples 7 to 12, the additive amount is 1% by mass, and the refractive index is However, since there was almost no change, the transmission clarity was very high. If it is necessary to add a large amount of the additive, it is preferable to adjust the compounding of the resin composition for forming the shaped resin layer so that the refractive index is substantially the same as that of the embedded resin layer.

  When Example 9 and Example 11 are compared, the presence or absence of the ZnO layer as the outermost layer of the wavelength selective reflection film is greatly different, and these spectral spectra are almost the same, but the adhesion with the embedded resin layer is the surface layer. Example 9 in which ZnO was present was higher.

The following can be understood from the evaluation results of FIGS. 36 to 40 and Tables 6 and 7.
The optical films of Comparative Examples 9 and 11 to 13 have a reflection hue of reddish purple to purple, and show a reflection color that is of concern when pasted on a window glass. In the optical film of Comparative Example 10, the red reflection was not worrisome, but among the near infrared rays necessary to block the heat of sunlight, the reflectance at a wavelength of 800 to 900 nm was as low as 50% or less, It is difficult to achieve both redness and heat shielding performance.
On the other hand, in the optical films of Examples 7 to 10 and 12, since the reflected light recurs in the direction of the light source, the reflected color is not recognized and the sunlight is reflected and transmitted. However, only a blue-green color was recognized, and it was a preferable color tone that felt cool when applied to a window. For example, the optical film of Example 9 has the same film configuration as that of Comparative Example 11, and has high infrared reflectivity. Thus, when the film of a present Example is applied, a preferable external color and infrared shielding performance can be made compatible.

(Example 13)
First, a Ni-P die roll having a fine triangular pyramid shape shown in FIGS. 35A and 35B was produced by cutting with a cutting tool. Next, a urethane acrylate (manufactured by Toagosei Co., Ltd., Aronix, refractive index 1.533 after curing) is applied onto a 75 μm thick PET film (A4300, manufactured by Toyobo Co., Ltd.), and UV is applied from the PET film side in a state of being in close contact with the mold. The urethane acrylate was cured by irradiation with light. Next, the laminate of the resin layer obtained by curing urethane acrylate and the PET film was peeled from the Ni-P mold. Thereby, a resin layer (hereinafter referred to as a shape resin layer) provided with a triangular pyramid shape was formed on the PET film. Next, a wavelength selective reflection film having the reflection film A shown in Table 9 was formed on the molding surface having a triangular pyramid shape formed by a mold by sputtering. An alloy target having a composition of Ag / Pd / Cu = 99.0 at% / 0.4 at% / 0.6 at% was used for forming the AgPdCu film.

  Next, using the manufacturing apparatus shown in FIG. 23, the film formation surface of the shaped film was embedded with resin as follows. That is, a resin composition having the following composition is applied onto a 75 μm-thick smooth PET film (Toyobo, A4300), and a wavelength selective reflection film is formed on the surface so that air bubbles do not enter between the two films. A smooth PET film was laminated with a PET film. Thereafter, the resin composition was cured by irradiating UV light from the smooth PET film side. Thereby, the resin composition between the smooth PET film and the wavelength selective reflection film was cured, and a resin layer (hereinafter referred to as an embedded resin layer) was formed. Thus, the objective optical film of Example 13 was obtained.

<Formulation of resin composition>
99 parts by mass of urethane acrylate (manufactured by Toagosei, Aronix, refractive index after curing 1.533)
2-acryloyloxyethyl acid phosphate 1 part by mass (Kyoei Chemical Co., Ltd., light acrylate P-1A)
However, the urethane acrylate contains a photopolymerization initiator and the like.

(Example 14)
An optical film of Example 14 was obtained in the same manner as Example 13 except that the embedding resin layer had the following composition.

<Formulation of resin composition>
98 parts by mass of urethane acrylate (Toagosei, Aronix, refractive index after curing 1.533)
2-acryloyloxyethyl acid phosphate 2 parts by mass (Kyoei Chemical Co., Ltd., light acrylate P-1A)

(Example 15)
An embedded resin layer having the following composition, the composition of the shape resin layer was changed to match the refractive index of the shape resin layer, and the refractive index after curing was changed to 1.530. 15 optical films were obtained.

<Composition of upper layer resin composition>
95 parts by mass of urethane acrylate (Toagosei Co., Ltd., Aronix, refractive index after curing 1.533)
2-acryloyloxyethyl acid phosphate 5 parts by mass (Kyoei Chemical Co., Ltd., light acrylate P-1A)

(Example 16)
An optical film of Example 16 was obtained in the same manner as Example 15 except that the embedding resin layer had the following composition.
<Composition of upper layer resin composition>
95 parts by mass of urethane acrylate (Toagosei Co., Ltd., Aronix, refractive index after curing 1.533)
2-Methacryloyloxyethyl acid phosphate 5 parts by mass (Kyoei Chemical Co., Ltd., light acrylate P-2M)

(Example 17)
An optical film of Example 17 was obtained in the same manner as Example 13 except that the wavelength selective reflection film was changed to the reflection film B shown in Table 9. An alloy target of Ag / Bi = 99.0 at% / 1.0 at% was used at the time of AgBi film formation, and an Nb ₂ O ₅ ceramic target was used at the time of Nb ₂ O ₅ film formation.

(Example 18)
An optical film of Example 18 was obtained in the same manner as Example 17 except that the wavelength selective reflection film was changed to the reflection film C shown in Table 9.

(Example 19)
An optical film of Example 19 was obtained in the same manner as Example 13 except that the wavelength selective reflection film was changed to the reflection film D shown in Table 9.

(Example 20)
An optical film of Example 20 was obtained in the same manner as Example 13 except that the embedding resin layer and the shape resin layer had the following composition.
<Composition of upper layer resin composition>
70 parts by mass of urethane acrylate (Toagosei, Aronix, refractive index after curing 1.533)
30 parts by mass of 2-acryloyloxyethyl-succinic acid (manufactured by Kyoei Chemical Co., HOA-MS)

(Example 21)
An optical film of Example 21 was obtained in the same manner as in Example 13 except that the embedding resin layer and the shape resin layer had the following composition.
85 parts by mass of urethane acrylate (Toagosei, Aronix, refractive index after curing 1.533)
15 parts by mass of γ-butyrolactone methacrylate (Osaka Organic Chemical Co., Ltd., GBLMA)

(Example 22)
An optical film of Example 22 was obtained in the same manner as Example 13 except that the embedding resin layer had the same composition as the shape resin layer.

(Example 23)
An optical film of Example 23 was obtained in the same manner as Example 13 except that the embedding resin layer and the shape resin layer had the following composition.
99 parts by mass of urethane acrylate (manufactured by Toagosei, Aronix, refractive index after curing 1.533)
2-acryloyloxyethyl acid phosphate 1 part by mass (Kyoei Chemical Co., Ltd., light acrylate P-1A)

(Reflective film adhesion evaluation)
The produced optical film was bonded to 3 mm-thick glass with an optically transparent adhesive, and the end of the film was peeled off to observe the state. The evaluation results are shown in Table 8.
◎: Peeling is difficult, and if it is forcibly removed, bulk destruction of the substrate or resin occurs. ○: Peeling is relatively difficult, but if it is forcibly removed, peeling occurs at the interface. Δ: Peeling occurs at the interface. However, I feel resistance when peeling ×: Interfacial peeling occurs without resistance

(Ni-P releasability evaluation)
A Ni-P flat plate mold having a fine triangular pyramid shape shown in FIG. 35 is manufactured by cutting with a cutting tool, and after applying each resin, a 75 μm-thick PET film (Toyobo, A4300) is put on and adhered to the mold. In this state, 1000 mJ / cm ^{2 of} UV light was applied from the PET film side to cure the resin. The laminate of this resin and PET film was peeled off from the Ni-P mold and the releasability was evaluated. The evaluation results are shown in Table 8.
○: Easy to mold after curing Δ: Mold can be released after curing, but some resin remains in the mold and uneven shape film appears.

(Vividness evaluation)
The produced optical film was bonded to 3 mm-thick glass with an optically transparent adhesive. Next, this glass was held about 50 cm away from the eyes, the inside of an adjacent building at a distance of about 10 m was observed through the glass, and evaluated according to the following criteria. The evaluation results are shown in Table 8.
○: Multiple images due to diffraction are hardly seen, and there is no problem in use as a window. Δ: The approximate shape of the object can be distinguished, but the multiple images due to diffraction are anxious. ×: What is cloudy due to the influence of diffraction, etc. I don't know if there is

Table 8 shows the structures and evaluation results of the optical films of Examples 13 to 23. However, since Example 23 was not released, a sample for evaluation of adhesion could not be produced.

Table 9 shows the film configuration of the wavelength selective reflection film of the optical films of Examples 13 to 23.

(Test Example 1)
First, a ZnO film was formed to a thickness of 20 nm on a glass plate by a vacuum sputtering method to produce a test piece. Next, the amount of 2-acryloyloxyethyl acid phosphate (manufactured by Kyoei Chemical Co., Light Acrylate P-1A) is added to the acrylic resin composition (Toagosei Co., Ltd., Aronix, post-curing refractive index 1.533). They were added as shown in Table 10. Thereby, the acrylic resin composition from which the addition amount of an additive differs was obtained. Next, after applying these acrylic resin compositions to the prepared test pieces, they were covered with a ZEONOR film, and the resin was cured by irradiation with 1000 mJ / cm ^{2 of} UV light. Thus, a target sample was obtained.

(Test Example 2)
The test was conducted in the same manner as in Test Example 1 except that 2-methacryloyloxyethyl acid phosphate (manufactured by Kyoei Chemical Co., Ltd., light acrylate P-2M) was used as an additive, and the addition amount was changed as shown in Table 10. A piece was made.

(Test Example 3)
Using 2-acryloyloxyethyl-succinic acid (manufactured by Kyoei Chemical Co., Ltd., HOA-MS) as an additive and changing the addition amount as shown in Table 10, the test piece was prepared in the same manner as in Test Example 1. Produced.

(Test Example 4)
Test pieces were prepared in the same manner as in Test Example 1 except that γ-butyrolactone methacrylate (manufactured by Osaka Organic Chemical Co., Ltd., GBLMA) was used as an additive and the amount added was changed as shown in Table 10.

(Adhesion evaluation)
Next, it was produced as described above, the ZEONOR film was peeled from the test piece, the resin was cross-cut into 100 squares with a cutter, and an adhesion test was performed. The evaluation results are shown in Table 10.
A: High adhesion, no peeling
○: Relatively strong adhesion, peeling 0-20
Δ: Adhesion is relatively weak, peeling 20-50
X: Adhesion is weak, peeling 50-100

Table 10 shows the evaluation results of the samples of Test Examples 1 to 4.

Table 10 shows the following.
It can be seen that the adhesiveness is improved by adding a relatively small amount of phosphoric acid based additive of about 0.5%. On the other hand, with succinic acid-based and butyrolactone acid-based additives, it was found that adhesion is improved by adding a relatively large amount of about 20% or more.

(Test Example 5)
First, a Ni-P flat plate mold having a fine triangular shape shown in FIG. 35 was manufactured by cutting with a cutting tool. Next, the amount of 2-acryloyloxyethyl acid phosphate (manufactured by Kyoei Chemical Co., Light Acrylate P-1A) is added to the acrylic resin composition (Toagosei Co., Ltd., Aronix, post-curing refractive index 1.533). They were added as shown in Table 11. Thereby, the acrylic resin composition from which the addition amount of an additive differs was obtained. Next, these acrylic resin compositions were apply | coated to the shape surface of the produced Ni-P flat plate metal mold | die. Next, a PET film (A4300, manufactured by Toyobo Co., Ltd.) having a thickness of 75 μm was covered, and the resin was cured by irradiation with 1000 mJ / cm ^{2 of} UV light from the PET film in a state where the PET film was closely attached to the mold. Thus, a target sample was obtained.

(Test Example 6)
A sample was prepared in the same manner as in Test Example 5 except that 2-methacryloyloxyethyl acid phosphate (manufactured by Kyoei Chemical Co., Ltd., light acrylate P-2M) was used as an additive, and the addition amount was changed as shown in Table 11. Was made.

(Test Example 7)
A sample was prepared in the same manner as in Test Example 5 except that 2-acryloyloxyethyl-succinic acid (manufactured by Kyoei Chemical Co., Ltd., HOA-MS) was used as an additive, and the addition amount was changed as shown in Table 11. did.

(Test Example 8)
A sample was prepared in the same manner as in Test Example 5 except that γ-butyrolactone methacrylate (manufactured by Osaka Organic Chemical Co., Ltd., GBLMA) was used as the additive and the addition amount was changed as shown in Table 11.
(Releasability evaluation)
Next, the laminate of the cured resin layer and the PET film was peeled from the Ni-P flat plate mold to evaluate the releasability. The evaluation results are shown in Table 11.
○: Can be easily peeled after curing Δ: Can be peeled after curing, but some resin remains in the mold, and unevenness is visible on the shape film ×: After curing, cannot adhere to the mold and peel

Table 11 shows the evaluation results of the samples of Test Examples 5 to 8.

Table 11 shows the following.
It was found that a product with zero additive peels easily from the mold, but a product containing at least 1% of an additive for improving adhesion has a problem in peelability. In particular, the addition of a phosphoric acid-based additive that improves adhesion in a small amount completely adheres to the mold with 1% addition, whereas the butyrolactone-based resin with relatively poor adhesion has a resin added with 1% addition. It can be seen that it cannot be used for shape transfer because it remains in some molds.

  Although the embodiments and examples of the present invention have been specifically described above, the present invention is not limited to the above-described embodiments, and various modifications based on the technical idea of the present invention are possible.

  For example, the configurations, shapes, materials, numerical values, and the like given in the above-described embodiments and examples are merely examples, and different configurations, shapes, materials, numerical values, and the like may be used as necessary.

  The configurations of the above-described embodiments can be combined with each other without departing from the gist of the present invention.

  Moreover, although the above-mentioned embodiment demonstrated the example which forms the 2nd optical layer 5 with a smooth surface using the film 22 for peeling, the formation method of a surface is not limited to this example. For example, a hot melt resin, an ionizing radiation curable resin, or the like may be applied on the concavo-convex surface of the wavelength selective reflection film 3, and a flat surface may be formed using a mirror roll. Further, a flat surface may be formed by applying an easily leveling resin such as an ionizing ray curable resin or a thermosetting resin on the uneven surface. Furthermore, the step of applying the resin on the uneven surface may be omitted, and the adhesive may be applied to the uneven surface of the wavelength selective reflection film 3 and leveled to form a flat surface.

  In the above-described embodiment, the case where the directional reflector according to the present invention is applied to a window material or the like has been described as an example. However, the directional reflector according to the present invention may be applied to a blind or a roll curtain. As the blind or roll curtain to which the directional reflector is applied, for example, a blind or roll curtain constituted by the directional reflector itself, a blind or roll curtain constituted by a transparent substrate on which the directional reflector is bonded, etc. Can be mentioned. By installing such a blind or a roll curtain near the indoor window, for example, only infrared rays can be directionally reflected outdoors and visible light can be taken into the room. Therefore, the need for room lighting is reduced even when blinds or roll curtains are installed. Moreover, since there is no scattering reflection by a blind or a roll curtain, the surrounding temperature rise can also be suppressed. Further, when the necessity for heat ray reflection is low such as in winter, there is an advantage that the heat ray reflection function can be easily used properly depending on the situation by raising the blinds or the roll curtain. On the other hand, conventional blinds and roll curtains for shielding infrared rays are coated with infrared reflecting paints and have a white, gray, or cream appearance, so try to block the infrared rays. Then, visible light is also cut off at the same time, and indoor lighting is required. Similarly, it can take the form of a shoji, and can be removed if it is not necessary.

DESCRIPTION OF SYMBOLS 1 Directional reflector 2 Optical layer 3 Wavelength selective reflection film 4 1st optical layer 4a 1st base material 4b 1st resin layer 5 2nd optical layer 5a 2nd base material 5b 2nd resin layer 6 Self Cleaning effect layer 7 Light scattering layer 8 Bonding layer 9 Optical layer with reflection film 10 Window material 11 Structure 12 Fine particles 21 Transparent resin 22 Film for peeling 23 Light source 31 Bead 32 Focus layer 41 Window material 42 Structure 43 Optical layer 71 Barrier layer 72 Hard coat layer 73 Coupling agent layer 74 Antifouling layer S Incident surface L Incident light L1 Reflected light L2 Transmitted light

Claims (16)

An optical layer having an incident surface on which light is incident;
A wavelength selective reflection film formed in the optical layer,
Incident angles (θ, φ) (where θ is an angle formed by a perpendicular to the incident surface and incident light incident on the incident surface or reflected light emitted from the incident surface, φ: identification within the incident surface Of the light incident on the incident surface at the angle of the straight line and the component of the incident light or the reflected light projected onto the incident surface) is specularly reflected (−θ, φ + 180 °). In contrast to selectively directional reflection in a direction other than the above, it transmits light other than the specific wavelength band,
The wavelength selective reflection film has a first main surface and a second main surface,
A first optical layer formed on the first main surface of the wavelength selective reflection film; a second optical layer formed on the second main surface of the wavelength selective reflection film; With
The first optical layer has a one-dimensional array structure body to the face where the wavelength-selective reflective layer is formed,
An optical body in which a main axis of the structure is inclined in an arrangement direction of the structures with respect to a normal of the incident surface.   The optical body according to claim 1, wherein a difference in refractive index between the first optical layer and the second optical layer is 0.010 or less.   2. The optical device according to claim 1, wherein the first optical layer and the second optical layer are made of the same resin having transparency in a visible light region, and the second optical layer contains an additive. body. The structure is a prism shape or optical body of claim 1, wherein a cylindrical shape.   The optical body according to claim 1, wherein the pitch of the structures is 30 μm or more and 5 mm or less.   The optical body according to any one of claims 1 to 5, wherein a direction φ of directional reflection with respect to light in the specific wavelength band is −90 ° or more and 90 ° or less.   The optical body according to any one of claims 1 to 5, wherein the directionally reflected light is mainly near-infrared light having a wavelength band of 780 nm to 2100 nm.   The wavelength selective reflection film is a transparent conductive film whose main component is a conductive material having transparency in the visible light region, or a functional film whose main component is a chromic material whose reflection performance is reversibly changed by an external stimulus. The optical body of any one of Claims 1-5. The wavelength selective reflection film is composed of a plurality of wavelength selective reflection films inclined with respect to the incident surface,
The optical body according to claim 1, wherein the plurality of wavelength selective reflection films are arranged in parallel to each other.   The optical body according to claim 1, wherein the optical layer absorbs light in a specific wavelength band in the visible region.   The light scatterer is further provided in at least 1 place among the surface of the said optical layer, the inside of the said optical layer, and between the said wavelength selection reflection film and the said optical layer. Optical body.   The optical body according to claim 1, further comprising a layer having water repellency or hydrophilicity on the incident surface of the optical body. A window member comprising the optical body according to any one of claims 1 to 12 . Blind comprising an optical body according to any one of claims 1 to 12. Roll curtain comprising an optical body according to any one of claims 1 to 12. A shoji comprising the optical body according to any one of claims 1 to 12 .